THE ENVIRONMENT A REVOLUTION IN ATTITUDES
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THE ENVIRONMENT A REVOLUTION IN ATTITUDES Kim Masters Evans...
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THE ENVIRONMENT A REVOLUTION IN ATTITUDES
ISSN 1532-207X
THE ENVIRONMENT A REVOLUTION IN ATTITUDES Kim Masters Evans
INFORMATION PLUS â REFERENCE SERIES Formerly Published by Information Plus, Wylie, Texas
The Environment: A Revolution in Attitudes Kim Masters Evans Paula Kepos, Series Editor Project Editor John McCoy
Composition and Electronic Prepress Evi Seoud
Manufacturing Drew Kalasky
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TABLE OF CONTENTS
P R E F A C E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
reductions in the pollution that causes acid rain through legislation and other measures.
CHAPTER 1
The State of the Environment—An Overview . . . . . . . 1 Public opinion and knowledge about environmental issues have evolved over time and have led to federal and state laws protecting environmental resources. These laws have been debated on their economic impacts and on how well they protect citizens from environmental hazards and crimes. The international community is also concerned about the environment and has, with varying degrees of success, implemented environmental standards of protection.
CHAPTER 6
Nonhazardous Waste . . . . . . . . . . . . . . . . . . . . . . 73 The vast majority of waste generated by modern society is not inherently hazardous. It includes paper, wood, plastics, glass, nonhazardous metals and chemicals, and other materials. Landfilling, incineration, and combustion are the most common disposal methods for nonhazardous waste. These methods, however, have environmental consequences that must be mitigated through design and control techniques.
CHAPTER 2
Air Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Emissions of chemicals from automobiles, factories, and power plants are mostly to blame for air pollution, which can make people sick and harm the environment. Government regulation, along with the implementation of new technologies, is designed to promote clean air, but some people believe these measures do not go far enough. CHAPTER 3
The Enhanced Greenhouse Effect and Climate Change 37 Scientists generally agree that the Earth is getting warmer, and many scientists believe that an enhanced greenhouse effect accounts for this change. Gases such as carbon dioxide, methane, nitrous oxide, and chlorofluorocarbons may be causing global warming, which could have severe effects on the Earth. Many nations have committed themselves to reducing greenhouse gas emissions. CHAPTER 4
A Hole in the Sky: Ozone Depletion . . . . . . . . . . . . 55 Ozone can be either a health hazard or a health protectant, depending on where in the atmosphere it is located. Manmade chemicals, such as chlorofluorocarbons, can deplete the protective layer of ozone found in the upper atmosphere, which protects humans, plants, and animals from excess UV radiation exposure. The international community plays an important role in safeguarding environmental health by protecting the ozone layer. CHAPTER 5
Acid Rain. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Combustion of fossil fuels emits sulfur oxides and nitrogen oxides into the atmosphere, leading to acid rain. Acid rain can harm human health and damage ecosystems. Politicians and environmental groups in the United States and worldwide have sought
The Environment
CHAPTER 7
Nonhazardous Materials Recovery—Recycling and Composting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Problems associated with the disposal of nonhazardous wastes have created a greater need for recovery of materials through recycling and composting. These methods save landfill space, conserve the energy that would be used for incineration, reduce environmental degradation and use of new resources, generate jobs and small-scale enterprise, reduce dependence on foreign imports of materials, and conserve water. However, their implementation and success are dependent upon public participation, government regulation, and economic factors. CHAPTER 8
Hazardous and Radioactive Waste . . . . . . . . . . . . .101 The most toxic and dangerous waste materials are those classified by the government as hazardous or radioactive. The storage, transport, and disposal of these wastes require special consideration, subjecting them to strict regulatory control and intense public scrutiny. Federal and state governments try to ensure that these wastes are managed in a way to protect the environment and public health. CHAPTER 9
Water Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . .117 Water is an essential resource necessary for sustaining all forms of life, but human alteration of the environment and patterns of water usage can have a devastating affect on the water supply. Legislation, including the Clean Water Act, seeks to improve and protect the integrity of America’s surface water, groundwater, oceans, coastal water, and drinking water. How effective such laws have been is a matter of debate.
v
CHAPTER 10
CHAPTER 11
Toxins in Everyday Life . . . . . . . . . . . . . . . . . . . .135
Depletion and Conservation of Natural Resources . . .151
Many of the substances naturally found in the environment or released by modern, industrialized society are poisonous at certain dosages. They may be found in the home, workplace, or backyard, in the food and water people eat and drink, and in medications and consumer products. Common toxins include metals, pesticides, and other chemicals; radiation, particularly from radon exposure; indoor air pollutants, such as asbestos and mold; and foodborne contaminants, including pathogens. These toxins can have damaging effects on the environment and human health.
Forests, wetlands, soils, minerals, and oil, as well as entire ecosystems are endangered by the activities of humans. The diversity of life on Earth (biodiversity) is also at risk, with many species facing extinction. Local, national, and international efforts must be linked to deal with pressures on the environment.
vi
Table of Contents
I M P O R T A N T N A M E S A N D A D D R E S S E S . . . . . . .171 R E S O U R C E S . . . . . . . . . . . . . . . . . . . . . . . . . . .173 I N D E X . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .175
The Environment
PREFACE
The Environment: A Revolution in Attitudes is part of the Information Plus Reference Series. The purpose of each volume of the series is to present the latest facts on a topic of pressing concern in modern American life. These topics include today’s most controversial and most studied social issues: abortion, capital punishment, care for the elderly, crime, the environment, health care, immigration, minorities, national security, social welfare, women, youth, and many more. Although written especially for the high school and undergraduate student, this series is an excellent resource for anyone in need of factual information on current affairs. By presenting the facts, it is Thomson Gale’s intention to provide its readers with everything they need to reach an informed opinion on current issues. To that end, there is a particular emphasis in this series on the presentation of scientific studies, surveys, and statistics. These data are generally presented in the form of tables, charts, and other graphics placed within the text of each book. Every graphic is directly referred to and carefully explained in the text. The source of each graphic is presented within the graphic itself. The data used in these graphics are drawn from the most reputable and reliable sources, in particular from the various branches of the U.S. government and from major independent polling organizations. Every effort has been made to secure the most recent information available. The reader should bear in mind that many major studies take years to conduct, and that additional years often pass before the data from these studies are made available to the public. Therefore, in many cases the most recent information available in 2006 dated from 2003 or 2004. Older statistics are sometimes presented as well if they are of particular interest and no more recent information exists. Although statistics are a major focus of the Information Plus Reference Series, they are by no means its only The Environment
content. Each book also presents the widely held positions and important ideas that shape how the book’s subject is discussed in the United States. These positions are explained in detail and, where possible, in the words of their proponents. Some of the other material to be found in these books includes: historical background; descriptions of major events related to the subject; relevant laws and court cases; and examples of how these issues play out in American life. Some books also feature primary documents or have pro and con debate sections giving the words and opinions of prominent Americans on both sides of a controversial topic. All material is presented in an evenhanded and unbiased manner; the reader will never be encouraged to accept one view of an issue over another. HOW TO USE THIS BOOK The condition of the world’s environment is an issue of great concern to both Americans and people worldwide. Since the late nineteenth century, humankind’s ability to alter the natural world, both deliberately and unintentionally, has increased. Many people fear that without proper restraint, humankind’s actions could forever alter, or even eliminate, life on Earth. There are those, however, who feel that these fears are exaggerated and that the substantial cost of environmental protection on business and industry should be minimized. The conflict between these two positions has serious environmental, political, and economic ramifications, both within the United States and worldwide. This book examines the steps that have been taken to protect the Earth’s natural environment, and the controversies that surround them.
The Environment: A Revolution in Attitudes consists of eleven chapters and three appendices. Each of the chapters is devoted to a particular aspect of the environment. For a summary of the information covered in each chapter, please see the synopses provided in the Table of Contents vii
at the front of the book. Chapters generally begin with an overview of the basic facts and background information on the chapter’s topic, then proceed to examine subtopics of particular interest. For example, Chapter 8: Hazardous and Radioactive Waste begins by defining hazardous waste and describing the laws and agencies that regulate it. It then describes the major sources of hazardous waste, namely industrial sites, as well as the sources of household hazardous waste. The chapter then moves to a detailed discussion of how hazardous waste is dealt with, such as source reduction, recycling, and treatment. Discussion of hazardous waste concludes with a section on the Superfund program discussing how contaminated sites are dealt with. The second half of the chapter covers radioactive waste, starting with the nature and sources of such waste. The difficulties of dealing with the most dangerous types of radioactive waste, including the public fear of these wastes, is discussed. The chapter ends with an examination of proposed long-term repositories for radioactive waste and the controversies surrounding them. Throughout the chapter special consideration is given to the problem of hazardous waste and the various methods used to clean up contaminated areas. Readers can find their way through a chapter by looking for the section and subsection headings, which are clearly set off from the text. Or, they can refer to the book’s extensive Index if they already know what they are looking for. Statistical Information The tables and figures featured throughout The Environment: A Revolution in Attitudes will be of particular use to the reader in learning about this issue. The tables and figures represent an extensive collection of the most recent and important statistics on the environment, as well as related issues—for example, graphics in the book cover the amounts of different kinds of pollutants found in air across the United States; the major sources of groundwater pollution; the amount of wetland that is destroyed each year; and public opinion on whether the state of the environment has become better or worse in the last five years. Thomson Gale believes that making this information available to the reader is the most important way in which we fulfill the goal of this book: to help readers understand the issues and controversies surrounding the environment and reach their own conclusions about them.
Each table or figure has a unique identifier appearing above it, for ease of identification and reference. Titles for the tables and figures explain their purpose. At the end of each table or figure, the original source of the data is provided. In order to help readers understand these often complicated statistics, all tables and figures are explained in the text. References in the text direct the reader to the relevant statistics. Furthermore, the contents of all tables and figures are fully indexed. Please see the opening
viii
Preface
section of the Index at the back of this volume for a description of how to find tables and figures within it. Appendices In addition to the main body text and images, The Environment: A Revolution in Attitudes has three appendices. The first is the Important Names and Addresses directory. Here the reader will find contact information for a number of government and private organizations that can provide further information on aspects of the environment. The second appendix is the Resources section, which can also assist the reader in conducting his or her own research. In this section the author and editors of The Environment: A Revolution in Attitudes describe some of the sources that were most useful during the compilation of this book. The final appendix is the Index. It has been greatly expanded from previous editions and should make it even easier to find specific topics in this book. ADVISORY BOARD CONTRIBUTIONS The staff of Information Plus would like to extend its heartfelt appreciation to the Information Plus Advisory Board. This dedicated group of media professionals provides feedback on the series on an ongoing basis. Their comments allow the editorial staff who work on the project to continually make the series better and more userfriendly. Our top priorities are to produce the highestquality and most useful books possible, and the Advisory Board’s contributions to this process are invaluable.
The members of the Information Plus Advisory Board are: • Kathleen R. Bonn, Librarian, Newbury Park High School, Newbury Park, California • Madelyn Garner, Librarian, San Jacinto College— North Campus, Houston, Texas • Anne Oxenrider, Media Specialist, Dundee High School, Dundee, Michigan • Charles R. Rodgers, Director of Libraries, Pasco– Hernando Community College, Dade City, Florida • James N. Zitzelsberger, Library Media Department Chairman, Oshkosh West High School, Oshkosh, Wisconsin COMMENTS AND SUGGESTIONS The editors of the Information Plus Reference Series welcome your feedback on The Environment: A Revolution in Attitudes. Please direct all correspondence to:
Editors Information Plus Reference Series 27500 Drake Rd. Farmington Hills, MI 48331-3535
The Environment
CHAPTER 1
THE STATE OF THE ENVIRONMENT—AN OVERVIEW
We have not inherited the Earth from our fathers. We are borrowing it from our children. —Native American saying
Photographs from outer space impress on the world that humankind shares one planet, and a small one at that. (See Figure 1.1.) Earth is one ecosystem. There may be differences in race, nationality, religion, and language, but everyone resides on the same orbiting planet. General concern about the environment is a relatively recent phenomenon. Two closely related factors explain the rising concern during the second half of the twentieth century: global industrialization following World War II and the worldwide population explosion. It was once thought that the life-sustaining resources of planet Earth were infinite; now it is known that these resources are finite and limited. HISTORICAL ATTITUDES TOWARD THE ENVIRONMENT The Industrial Revolution Humankind has always altered the environment around itself. For much of human history, however, these changes were fairly limited. The world was too vast and people too few to have more than a minor effect on the environment, especially as they had only primitive tools and technology to aid them. All of this began to change in the 1800s. First in Europe and then in America, powerful new machines, such as steam engines, were developed and put into use. These new technologies led to great increases in the amount and quality of goods that could be manufactured and the amount of food that could be harvested. As a result, the quality of life rose substantially and the population began to boom. The so-called Industrial Revolution was underway.
While the Industrial Revolution enabled people to live better in many ways, it also increased pollution. For many years pollution was thought to be an insignificant side The Environment
effect of growth and progress. In fact, at one time people looked on the smokestacks belching black soot as a healthy sign of economic growth. The reality was that pollution, along with the increased demands for natural resources and living space that resulted from the Industrial Revolution, was beginning to have a significant effect on the environment. Twentieth-Century America For much of the early twentieth century, Americans accepted pollution as an inevitable cost of economic progress. After World War II, however, more and more incidents involving pollution made people aware of the environmental problems caused by human activities. Los Angeles’s ‘‘smog,’’ a smoky haze of pollution that formed like a fog in the city, contributed a new word to the English language. Swimming holes became so polluted they were poisonous. Still, little action was taken.
In the 1960s environmental awareness began to increase, partly in response to the 1962 publication of Rachel Carson’s book Silent Spring (Boston, MA: Houghton Mifflin), which exposed the toll of the chemical pesticide DDT on bird populations. Other signs of the drastic effects of pollution on the environment became harder and harder to ignore. For example, in 1969 the Cuyahoga River near Cleveland, Ohio, burst into flames due to pollutants in the water. Environmental protection rapidly became very popular with the public, particularly with the younger generation. On November 30, 1969, the New York Times carried a lengthy article reporting on the astonishing increase in environmental interest. The article’s author, Gladwin Hill, noted that concern about the environmental crisis was especially strong on college campuses, where it was threatening to become even more of an issue than the Vietnam War. 1
With public opinion loudly expressed by the Earth Day demonstrations, in 1970 Congress and President Richard Nixon passed a series of unprecedented laws to protect the environment and created the Environmental Protection Agency (EPA), an organization devoted to setting limits on water and air pollutants and to investigating the environmental impact of proposed, federally funded projects. In the years that followed, many more environmental laws were passed, setting basic rules for interaction with the environment. Most notable among these laws were the Clean Air Act of 1970 (PL 91-604), the Clean Water Act of 1972 (PL 92-500), the Endangered Species Act of 1973 (PL 93-205), the Safe Drinking Water Act of 1974 (PL 93-523), and the Resource Conservation and Recovery Act of 1976 (PL 95-510).
FIGURE 1.1
THE STATUS OF ENVIRONMENTAL ISSUES IN THE UNITED STATES AT THE BEGINNING OF THE TWENTYFIRST CENTURY. Since the 1970s the state of the envi-
The Earth, as seen from a U.S. satellite. (U.S. National Aeronautics and Space Administration.)
FACTORS ACTIVISM. In
CONTRIBUTING
TO
ENVIRONMENTAL
1969, according to Opinion Research of Princeton, New Jersey, only 1.0% of Americans polled expressed concern about the environment. By 1971 fully one-quarter reported that protecting the environment was important. What motivated Americans to this new awareness? The following are among the likely factors: • An affluent economy and increased leisure time • The emergence of an ‘‘activist’’ upper middle class that was college educated, affluent, concerned, and youthful • The rise of television, an increasingly aggressive press, and advocacy journalism (supporting specific causes) • An advanced scientific community with increasing funding, new technology, and vast communication capabilities
EARTH DAY AND THE BIRTH OF ENVIRONMENTAL PROTECTION. The idea for Earth Day began to evolve
beginning in the early 1960s. Nationwide ‘‘teach-ins’’ were being held on campuses across the country to protest the Vietnam War. Democratic senator Gaylord Nelson of Wisconsin, troubled by the apathy of American leaders toward the environment, announced that a grassroots demonstration on behalf of the environment would be held in the spring of 1970 and invited everyone to participate. On April 22, 1970, twenty million people participated in massive rallies on American campuses and in large cities. Earth Day went on to become an annual event. 2
The State of the Environment—An Overview
ronment has continued to be a major political issue of interest to many Americans. Many activist organizations, such as Greenpeace and the Natural Resources Defense Council, have been created to watch over and protect the environment. Virtually every state has established one or more agencies charged with protecting the environment. Many universities and colleges offer programs in environmental education. Billions of dollars are spent every year by state and federal governments for environmental protection and enhancement. These efforts have, in turn, led to many improvements in the state of the environment. Many of the most dangerous chemicals that once polluted the air and water have either been banned or their emissions into the environment greatly reduced. Yet, other environmental problems have arisen or worsened since 1970, such as the possibility of global warming and the depletion of Earth’s natural resources. International conferences addressing these issues have produced mixed results. Some studies, such as Gallup polls, have suggested that concern about the environment declined in the 1990s. To explain this, many people point to the fact that obvious dangers, such as rivers on fire and belching smokestacks, have seen substantial improvement. Those dangers that remain, such as global warming and ozone depletion in the atmosphere, are largely invisible, and the public may not as easily accept or be concerned about their existence. Another factor in the decline in environmental activism is money. Many of the cheapest and easiest environmental problems to fix were resolved in the 1970s, 1980s, and 1990s. Most of the remaining problems at the end of the century were so large or complicated that it was believed that tremendous amounts of money would have to be spent before even modest improvements would be seen. Many Americans, especially those who felt their jobs were threatened by environmental regulaThe Environment
THE ROLE OF POPULATION IN THE ENVIRONMENTAL EQUATION Earth’s population is believed to have grown more from 1950 through 2000 than it did during the previous four million years. For centuries, deaths largely offset births, resulting in a slow population growth. Beginning around 1950, high birth rates in developing countries, coupled with a reduction in mortality rates and reduced infant mortality (which led to an overall lengthening of the life span), dramatically impacted population growth. According to 2003 figures from the United Nations (UN), between 1950 and 1990 the global population more than doubled from 2.5 billion to more than 5.0 billion people. Another billion people are estimated to have been added between 1990 and 2000.
As shown in Figure 1.2 the vast majority of population growth is expected in less developed countries. This is significant to environmental issues because these countries are, or will be, undergoing their own industrial revolutions—a time when economic development or ‘‘progress’’ generally gets priority over environmental issues. The growing number of people on Earth increases the demands on natural resources. More people require more food, water, fuel, clothing, and other necessities for life. All of these must be supplied from the planet’s resources and from the Sun’s energy. These facts—combined with the realization that the Earth’s resources are limited, not infinite—pose serious questions about rapid population growth. Can the world’s resources support its population while maintaining the environment, or will human needs overwhelm Earth’s capacity to provide? Most scientists believe that population growth will eventually cease. As a nation’s economy develops and its standards of living rise, its population generally stabilizes. This ‘‘demographic shift’’ has already been observed in highly industrialized countries such as Japan and the nations of western Europe where the fertility rate is generally at or below replacement level. The UN projects that this slow decline in growth rates will continue until all regions of Earth have developed high standards of living, experienced a demographic shift, and had their populations stabilize. By the time this The Environment
FIGURE 1.2
World population growth in more and less developed countries, 1950–2050
Less developed countries
More developed countries
10
8
6 Billions
tions, questioned whether these increased costs were worth the relatively small benefits they would provide. Despite the support of those who wanted to see further environmental improvements, such issues were competing for funds with other pressing issues such as acquired immune deficiency syndrome (AIDS), homelessness, and starvation in many parts of the world. In addition, since the terrorist attacks of September 11, 2001, environmental issues have been overshadowed by the threat of terrorism. Homeland security and military operations in Afghanistan and Iraq became funding priorities.
4
2
0 1950
1970
1990
2010
2030
2050
“Growth in More, Less Developed Countries,” in Graphics Bank: Population Trends, Population Reference Bureau, Washington, DC, 2003, www.prb.org/presentations/g_growth-MDCs-LDCs.ppt (accessed August 4, 2005) SOURCE:
occurs, however, Earth’s population is expected to have reached at least nine billion people. It is not known if Earth’s resources can support a population of nine billion. Some believe there is evidence that population growth is already pressing, or has exceeded, the capacity of natural resources in many areas. Environmentalists and others warn that without conservation, resource protection, and drastic measures to curb population, humankind and planet Earth might suffer serious harm. Other analysts do not share these opinions, however. Some analysts oppose the idea that natural resources and humankind are in danger and point to the fact that, at many times throughout history, there have been those who claimed that industrial development could not be sustained. For example, at one time it was feared that, as the world ran out of whale oil for lamps, great cities would be left in darkness. This scenario, and other ‘‘doomsday’’ predictions, did not come about because new technologies averted the expected disasters. THE IMPACT OF ENVIRONMENTAL PROTECTION ON THE U.S. ECONOMY How Government Regulations Work Since federal and state governments began actively protecting the environment in the 1970s, they have acted primarily by creating rules—called regulations—that say The State of the Environment—An Overview
3
how Americans can affect the environment around them. In order to get people and organizations to comply with these regulations, the government fines, imprisons, or otherwise punishes those who violate them. Most federal regulations are aimed at controlling the environmental practices of businesses and industries, as their behavior is much easier to monitor and control than that of individual citizens. For example, to reduce air pollution the government might regulate the lawn mower industry by not allowing it to make lawn mowers that release more than a certain amount of pollutants. This is much easier for the government than the alternative: checking how much pollution is released when an individual mows his or her lawn, and punishing that person if it is too much. Attitudes of Business toward Environmental Regulation All environmental regulations interfere with the way businesses would otherwise operate. They force businesses to design their products differently, install special machinery in their factories, or even stop certain activities entirely. In the most extreme cases, entire industries might be shut down, such as when the government determined that the chemical DDT, once widely used as a pesticide, was too hazardous to human health to be used at all.
The changes required to comply with environmental regulations almost always result in smaller profits for those companies affected by such restrictions. This is especially true for industries that extract natural resources, such as mining and logging; industries that produce a great deal of pollution, such as electrical power generation; and industries whose products are potentially hazardous, such as the chemical industry. Compliance with governmental regulations is a very significant cost item for some industries.
TABLE 1.1
Pollution abatement costs and expenditures by media protected in 1999
Air Water Solid waste Multimedia Total
Capital costs
Operating costs
$3,463.7 $1,801.9 $361.9 $182.3
$5,069.1 $4,586.5 $2,013.3 $195.5
Total costs $8,532.8 $6,388.4 $2,375.2 $377.8
$5,809.8
$11,864.4
$17,674.2
Adapted from “Summary of 1999 Survey Results,” in Pollution Abatement Costs and Expenditures: 1999, U.S. Department of Commerce, U.S. Census Bureau, Washington, DC, November 2002, http://www.census .gov/prod/2002pubs/ma200-99.pdf (accessed August 4, 2005) SOURCE:
FIGURE 1.3
Pollution abatement costs and expenditures, by industry, 1999 [$17.7 billion total]
Mining (operating costs) 3%
Electric utility industry (capital costs) 6% Electric utility industry (operating costs) 7%
Mining (capital costs) 2%
Manufacturing (capital costs) 25%
Manufacturing (operating costs) 57%
In November 2002 the U.S. Department of Commerce published the results from its latest survey of manufacturing, mining, and electric utility companies on their expenses for environmental compliance. In Pollution Abatement Costs and Expenditures: 1999 the agency reported that in 1999 manufacturing industries spent $5.8 billion on pollution abatement capital expenditures (such as equipment) and $11.9 billion on pollution abatement operating costs.
chemicals ($3.8 billion) and petroleum/coal product manufacturing ($1.7 billion).
A breakdown by media type protected is presented in Table 1.1. Protection of air and water accounted for more than 80% of the expenditures. As shown in Figure 1.3 the manufacturing industry paid $14.5 billion, the largest share (82%) of pollution abatement costs in 1999. The electric utility industry accounted for 13% of the costs, followed by mining with 5%. Within the manufacturing sector the two industries with the highest total costs were
It is not surprising that business and industry leaders object to these costs. Some claim that environmental regulations will make their businesses unprofitable by driving up prices and production costs, which will in turn force them to close plants and lay off workers, if not shut down entirely. As early as the 1970s these sentiments were finding support among politicians and the general population, and an antiregulatory movement developed.
4
The State of the Environment—An Overview
Adapted from “Summary of 1999 Survey Results,” in Pollution Abatement Costs and Expenditures: 1999, U.S. Department of Commerce, U.S. Census Bureau, Washington, DC, November 2002, http://www.census.gov/prod/2002pubs/ma200-99.pdf(accessed July 20, 2005)
SOURCE:
The Environment
layoffs that some businesspeople predicted had not come to pass. Michael Renner, in State of the World 2000 (New York: Worldwatch Institute and W. W. Norton Company, 2000), states that job loss as a result of environmental regulation has been relatively limited. According to Renner, at least as many people have gained jobs, due to the restrictions, as have lost them. He points out that environmental regulations have led to the creation of an entirely new industry that earns its profits by assisting other businesses with compliance, mostly by helping them to minimize pollution. Even for those who accept this positive view of the overall effects of environmental regulation on business, it is unquestionable that some industries and their workers are badly hurt by environmental regulations. Renner contends that policy changes intended to protect the environment must have a clear and predetermined schedule. This way workers will know in advance what is expected of them, what jobs will be in demand, and what training is needed to get them into those positions. As long as environmental regulation results in shrinking profits and loss of jobs, however, attempts to expand such regulation will certainly be met with opposition from those whose livelihood would be affected. The Business of Environmental Protection
In order for the United States and other nations to meet their environmental goals, an environmental protection industry has emerged. Its major activities include pollution control, waste management, cleanup of contaminated sites, pollution prevention, and recycling. Environmental Business International Inc. (EBI) is a private organization that offers business and market information to the environmental industry. According to EBI the U.S. environmental market was largely driven by major legislation during the 1970s and 1980s. (See Figure 1.4.) During the 1990s overall economic growth and adaptation of ISO standards were important factors driving the market. ISO standards are voluntary standards developed by the International Organization for Standardization (ISO). They were adopted by many industries during the 1990s as a means of showing compliance with certain levels of environmental conduct. The environmental industry is in a transition phase. In the past this industry focused on remedial cleanup; in the future it will be focused more on prevention. As shown in Figure 1.4 the environmental industry market underwent tremendous growth between 1970 and 2000. The U.S. market for pollution-control technologies and other environmental services topped $200 billion in 2000. Growth is expected to slow a little between 2000 and 2010. Table 1.2 details projected growth rates by The Environment
FIGURE 1.4
U.S. environmental industry market, 1970–2010
Services
Equipment
Resources
Economic growth, ISO standards
250 Billion dollars (nominal)
DOES ENVIRONMENTAL PROTECTION DESTROY JOBS? By the end of the twentieth century, the large-scale
200 150 100 50
Environmental legislation NEPA, CAA
0 1970
1980
1990
2000
2010 projected
Notes: ISO⫽International Organization for Standards; NEPA⫽National Environmental Policy Act; CAA⫽Clean Air Act. SOURCE: Andrew Paterson, “U.S. Environmental Market 1970–2010,” in Environmental Market Outlook to 2010, Briefing for EPA-NACEPT, Environmental Business International, San Diego, CA, June 11, 2002
sectors within the environmental industry. Wastewater treatment works and solid waste management are the only service sectors expected to increase their market shares. Remediation, hazardous waste management, and related consulting services are expected to continue to decline. According to EBI, developed nations represent about 90% of the global pollution-control industry; the United States alone accounts for approximately 40% of the industry. Pollution-control markets are, however, growing rapidly in other countries. Expansion in Asian markets will greatly depend on the region’s economic status. If the economy worsens, it may lead governments to give the environment less priority. Also, some governments, including many in eastern Europe and Russia, have a legacy of abusive environmental practices that increases their environmental needs but a lack of funding that limits an otherwise huge market for cleanup and new technology. THE ANTIREGULATORY MOVEMENT Since the mid-1980s dissatisfaction with government regulation has grown. In 1994 the newly elected Republican-controlled Congress attempted to strike down a wide variety of federal regulations, including environmental regulations that they considered overly burdensome. Bills were introduced to relax regulations established under the Clean Water Act, Endangered Species Act, the Superfund toxic-waste cleanup program, the Safe Drinking Water Act, and other environmental statutes. Much of that legislation ultimately failed to pass. However, congressional budget cuts for the agencies responsible for carrying out these acts meant that many of the laws were not strongly enforced. The State of the Environment—An Overview
5
TABLE 1.2
Growth expected in U.S. environmental industry sectors, 1970–2010 Environmental industry segment
1970 $
70–80 growth
80–90 growth
90–00 growth
00–10 growth
0.1 4.3 3.2 0.1 0.1 0.3
300% 116% 164% 550% 550% 367%
314% 116% 208% 921% 1,813% 761%
⫺26% 34% 45% ⫺15% 5% 21%
⫺33% 36% 20% ⫺49% ⫺36% ⫺21%
3.2 0.1 1.0 2.0 0.0
117% 100% 196% 105% 259%
95% 820% 258% 159% 418%
57% 84% 30% 20% 192%
31% 1% ⫺44% 24% 83%
5.7 1.2 0.3
109% 283% 420%
67% 197% 15%
53% 29% 87%
25% 28% 82%
$21.4
145%
178%
35%
12%
Services Analytical services Wastewater treatment works Solid waste management Hazardous waste management Remediation/industrial services Consulting & engineering Equipment Water equipment and chemicals Instruments & information systems Air pollution control equipment Waste management equipment Process & prevention technology Resources Water utilities Resource recovery (recycling) Environmental energy sources U.S. totals
Andrew Paterson, “Several Service Sectors Declining: Water, Energy Growing,” in Environmental Market Outlook to 2010, Briefing for EPA-NACEPT, Environmental Business International, San Diego, CA, June 11, 2002 SOURCE:
Several factors contributed to this reaction to federal regulation. During the early days of the environmental era, the United States was experiencing a post-World War II economic boom, leading Americans to regard regulatory costs as sustainable. During the 1970s and 1980s, as economic growth slowed, wages stagnated and Americans became uncertain about the future. An increasing number of Americans started to question the costs of environmental protection. They began to pay more attention to the business leaders and politicians who had claimed since the beginning of the environmental protection movement that regulations would hurt the economy and cost people jobs. Although the national economy improved tremendously in the 1990s, it did not eliminate people’s concerns about the potential negative effects of environmental regulations on the economy. The impact of environmental regulations on private property use has also played a very important role in the change in attitudes. The Endangered Species Act and the wetlands provisions of the Clean Water Act spurred a grassroots ‘‘private property rights’’ movement. Many people became concerned that these acts, as well as other legislation, would allow the government to ‘‘take’’ or devalue properties without compensation. For example, if federal regulations prohibited construction on a plot of land that was protected by law, then the owner of that land often felt that the government was unfairly limiting the use of his or her property. At the very least, the owner wanted government compensation for decreasing the monetary value of the land. Finally, there are those who feel that environmental regulation by the government, while not necessarily bad, 6
The State of the Environment—An Overview
has gone too far. Many people believe that the federal government has overstepped its authority and should allow state and local governments to make their own rules on environmental issues. Similarly, some people feel that existing regulations are too strict and should be relaxed in order to generate economic growth. LITIGATION AND ENVIRONMENTAL POLICY The courts have been an important forum for developing environmental policy because they allow citizens to challenge complex environmental laws and to affect the decision-making process. Both supporters and opponents of environmental protection have successfully used the courts to change environmental policy and law. Successful challenges can force the legislature to change laws or even have the law suspended as unconstitutional. A lawsuit can also be filed to seek compensation for harm to a person, property, or an economic interest. Sometimes, lawsuits have prompted the creation of entirely new laws such as the federal Superfund Law (1980) and the Toxic Substances Control Act (1976). Even the threat of a lawsuit, given the bad publicity it can bring, is sometimes enough to get a business or the government to change its behavior.
There are many different situations under which an individual or organization can go to court over environmental laws and regulations. One common occurrence is for an individual or group to sue the government in order to block a law or regulation from going into effect. For example, when the government halted logging in northwestern forests because of threats to endangered owls, The Environment
logging companies fought to halt enforcement of those protections because that would decrease the industry’s income and cause the loss of jobs.
• Greater proportions of Hispanic Americans and African-Americans than whites live in communities that fail to meet air quality standards.
Some lawsuits are filed not to block an environmental law or regulation from going into effect but because the claimants feel that the government owes them compensation for the negative effects of the law. In 1986 David Lucas bought two residential lots on a South Carolina barrier island. He planned to build houses on these lots, just as had been done on other nearby lots. At the time he bought the land this was entirely legal, but in 1988 South Carolina passed the Beachfront Management Act. Designed to protect the state’s beaches from erosion, it prohibited new construction on land in danger of eroding, which included the land Lucas owned.
• Higher percentages of hired farm workers in the United States are minorities that may experience pesticide-related illnesses as a result of their work.
Lucas went to court claiming that the Beachfront Management Act had violated the Fifth Amendment of the U.S. Constitution by preventing him from building on his property. The Fifth Amendment states, among other things, that no person’s ‘‘private property shall be taken for public use, without just compensation.’’ Lucas argued that preventing him from building on his property was equivalent to taking it, so the government of South Carolina had to compensate him for it. On June 29, 1992, the U.S. Supreme Court, in Lucas v. South Carolina Coastal Council (505 US 1003), agreed with Lucas in a 7–2 decision, and South Carolina was ordered to compensate him. Supporters of environmental protection also have filed lawsuits. These situations generally occur when people feel the government is not properly enforcing the law. Environmental groups like the Sierra Club and Greenpeace have sued the government on many occasions to compel it to officially recognize certain species as endangered. ENVIRONMENTAL JUSTICE—AN EVOLVING ISSUE The so-called environmental justice issue stems from concerns that racial minorities are disproportionately subject to environmental hazards. The EPA defines environmental justice as ‘‘the fair treatment and meaningful involvement of all people regardless of race, color, national origin, or income with respect to the development, implementation, and enforcement of environmental laws, regulations, and policies.’’
Examples of environmental injustice include the following claims: • Low-income Americans, especially minorities, may be more likely than other groups to live near landfills, incinerators, and hazardous waste facilities. • Low-income and African-American children often have higher than normal levels of lead in their blood. The Environment
• Low-income and minority fishermen who use fish as their sole source of protein are generally not well informed about the risk of eating contaminated fish from certain lakes, rivers, and streams. The environmental justice movement gained national attention in 1982 with a demonstration against the construction of a hazardous waste landfill in Warren County, North Carolina, a county with a predominantly AfricanAmerican population. A resulting 1983 congressional study found that, for three of four landfills surveyed, African-Americans made up the majority of the population living nearby and at least 26% of the population in those communities was below the poverty level. In 1987 the United Church of Christ published a nationwide study, Toxic Waste and Race in the United States, reporting that race was the most significant factor among the variables tested in determining locations of hazardous waste facilities. A 1990 EPA report (Environmental Equity: Reducing Risk for All Communities) concluded that racial minorities and low-income people bore a disproportionate burden of environmental risk. These groups were exposed to lead, air pollutants, hazardous waste facilities, contaminated fish, and agricultural pesticides in far greater frequencies than the general population. In 1992 the EPA established the Office of Environmental Justice to address environmental impacts affecting minority and low-income communities. In 1994 President Bill Clinton issued Executive Order 12,898 (Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations), requiring federal agencies to develop a comprehensive strategy for including environmental justice in their decision making. In October 2003 the United States Commission on Civil Rights (USCCR) published the report ‘‘Not in My Backyard: Executive Order 12,898 and Title VI as Tools for Achieving Environmental Justice.’’ The report examined the level to which various government agencies, including the EPA, had implemented Executive Order 12,898 and Title VI (the Civil Rights Act of 1964). Agency performance was based on four major criteria: • Collecting data on the health and environmental impacts of agency activities on ‘‘communities of color and low-income populations’’ The State of the Environment—An Overview
7
• Incorporating the principles of environmental justice into agency policies, programs, and activities • Allowing ‘‘affected communities’’ to participate in environmental decision-making processes • Granting ‘‘affected communities’’ access to scientific data and information related to the enforcement of Title VI and Executive Order 12,898 The report concluded that the EPA had experienced ‘‘limited success’’ in implementing the principles of environmental justice, but that ‘‘significant problems and shortcomings’’ still existed. A lack of commitment from agency leaders was cited as a major problem. Only four of the USCCR’s eight commissioners signed the report. The other four refused to sign noting in an attached letter that they believed the report was ‘‘based upon a misguided application of federal antidiscrimination law to complex environmental and public health problems.’’ The dissenting commissioners acknowledged that there are legitimate concerns about the health of people living near ‘‘environmental hazards.’’ They prefer that these issues be addressed under environmental laws, rather than civil rights laws. They complain that ‘‘environmental justice activists seek to create a federal civil rights claim every time an environmental or public health problem affects minorities.’’ In March 2004 a federal lawsuit against the chemical company Monsanto was settled for $300 million. The suit was spearheaded by a grassroots environmental group called Citizens against Pollution out of Anniston, Alabama. It was brought on behalf of 18,477 residents living in poor, mostly African-American neighborhoods in the city’s west end. The suit alleged that since the 1960s a Monsanto plant had discharged large amounts of polychlorinated biphenyls (PCBs) into a creek running through the area. PCBs are mixtures of synthetic organic chemicals that are now known to be extremely persistent in the environment and toxic to life. Lawyers had evidence linking PCB exposure to a variety of serious illnesses and even deaths suffered by members of the community over decades. Without admitting fault, Monsanto agreed to pay $300 million to settle the case. According to Ellen Barry in the Los Angeles Times (‘‘A Neighborhood of Poisoned Dreams,’’ April 13, 2004), the plaintiffs, who were originally thrilled with the settlement, were shocked when they learned the lawyers would receive $120 million of the money. This left $180 million to be split amongst thousands of plaintiffs, resulting in an average payout of only $7,725 per person. A case brought by a different set of plaintiffs in state court resulted in a settlement of $300 million to be split among 2,500 of them. An additional $75 million was earmarked toward cleanup efforts and $25 million was set aside to build a neighborhood health clinic. In total the lawsuits resulted in a settlement of 8
The State of the Environment—An Overview
nearly $700 million, the largest payout ever in a tort case (a civil action resulting from a wrongful act) involving toxic chemicals. In the spring of 2005 the EPA was forced to cancel a planned pesticide study after the media accused the agency of targeting low-income minority children as test subjects. The Children’s Health Environmental Exposure Research Study (CHEERS) was supposed to collect data on children’s exposure to household pesticides and chemicals. The study called for the monitoring of sixty young children (age three and less) in and around Jacksonville, Florida, with the help of the county health department. According to the EPA, volunteering families were to do the following things over a two-year period: • keep records of their normal pesticide usage • maintain an activity diary for their child and videotape some of the child’s everyday activities with a supplied video recorder • collect food and urine samples • put a small sensor badge on their child for several weeks • allow periodic visits by EPA researchers to collect data The EPA instructions for families noted that they were to follow their normal pesticide application routine and were not being asked to apply new or different pesticides in their homes. In addition to the video camera, each family was to receive cash compensation for their time. The EPA began publicizing the CHEERS study and asking for families to volunteer to participate in the fall of 2004. The issue became a public relations nightmare for the agency. Media stories pointed out that the study area contained many low-income minority neighborhoods. Critics accused the EPA of enticing poor families to expose their children to pesticides in return for cash and video cameras. Part of the funding for the study was to come from the American Chemistry Council, a trade group representing chemical manufacturers. This also aroused criticism about the intent of the study. The issue became highly politicized in March 2005 when confirmation hearings began for Stephen Johnson, the Bush administration’s choice to head the agency. Some Senate democrats threatened to block Johnson’s confirmation unless the study was canceled. The EPA insisted that the study objectives were being distorted by the media and for political reasons. However, in April 2005 the EPA canceled the CHEERS study. ‘‘NEW’’ CRIME—ENVIRONMENTAL CRIME Table 1.3 lists the major environmental and wildlife protection acts of the federal government. As recently as the 1980s very few Americans understood that harming The Environment
TABLE 1.3
Major federal environmental and wildlife protection acts Environmental protection acts Clean Air Act (CAA)—Prevent the deterioration of air quality Clean Water Act (CWA)—Regulate sources of water pollution Comprehensive Environmental Response, Compensation, and Liability (CERCLA or Superfund)—Address problems of abandoned hazardous waste sites Emergency Planning & Community Right-To-Know Act (EPCRA)—Help local communities protect public health, safety, and the environment from chemical hazards Federal Insecticide, Fungicide and Rodenticide Act (FIFRA)—Control pesticide distribution, sale, and use National Environmental Policy Act (NEPA)—The basic national charter for protection of the environment. It establishes policy, sets goals, and provides means for carrying out the policy. Oil Pollution Act of 1990 (OPA)—Prevent and respond to catastrophic oil spills Pollution Prevention Act (PPA)—Reduce the amount of pollution produced via recycling, source reduction, and sustainable agriculture Resource Conservation and Recovery Act (RCRA)—Protect human health and the environment from dangers associated with waste management Safe Drinking Water Act (SDWA)—Protect the quality of drinking water Toxic Substances Control Act (TSCA)—Test, regulate, and screen all chemicals produced in or imported into the U.S. Wildlife protection acts Bald and Gold Eagle Protection Act (BGEPA)—Provide a program for the conservation of bald and golden eagles Endangered Species Act (ESA)—Conserve the various species of fish, wild life, and plants facing extinction Lacey Act—Control the trade of exotic fish, wildlife, and plants Migratory Bird Treaty Act (MBTA)—Protect migratory birds during their nesting season
Adapted from “Major Environmental Laws,” in Guide to Environmental Issues, U.S. Environmental Protection Agency, Office of Enforcement and Compliance Assurance, Washington, D.C., June 26, 1998, http://www.epa.gov/epahome/laws.htm (accessed August 4, 2005) SOURCE:
the environment could be considered a crime. Since that time, however, a substantial portion of the American public has begun to recognize the seriousness of environmental offenses, believing that damaging the environment is a serious crime and that corporate officials should be held responsible for offenses committed by their firms. Even though the immediate consequences of an offense may not be obvious or severe, environmental crime is a serious problem and does have victims; the cumulative costs in damage to the environment and the toll to humans in illness, injury, and death can be considerable. Law enforcement agencies generally believe that successful criminal prosecution—even the threat of it— is the best deterrent to environmental crime. Under the dual sovereignty doctrine, both state and federal governments can independently prosecute environmental crimes without violating the double jeopardy or due process clauses of the U.S. Constitution. As attitudes toward environmental crimes have changed, the penalties for such offenses have become harsher. Federal criminal enforcement has grown from a misdemeanor penalty for dumping contaminants into waterways without a permit, to a felony for clandestine (secret) dumping. Several federal laws now include criminal penalties. Companies, their officials, and staff can be prosecuted for knowingly violating any one of a number of crimes. Such crimes include transporting hazardous waste to an unlicensed facility, storing and disposing of hazardous waste without a permit, failing to notify of a hazardous substance release, falsifying documents, dumping into a wetland, or violating air quality standards. Figure 1.5 shows the numbers of criminal investigations conducted by the EPA Criminal Enforcement The Environment
Program for fiscal years 2000–04 and the number of defendants charged with environmental crimes. More than four hundred investigations took place during 2004, and nearly three hundred defendants were charged with crimes that year. Nearly eight hundred people were incarcerated for environmental crimes between 2000 and 2004 and nearly $400 million in fines were paid. Another $545 million was collected in civil penalties. (See Figure 1.6.) Since the 1970s, environmental laws have become more complicated. The increasing strictness of those laws may have contributed to the growing incidence of environmental violations. First, many businesses have found compliance increasingly expensive, and many are simply avoiding the costs even if it means violating the law. These companies consider the penalties just another ‘‘cost of doing business.’’ Second, businesses and their legal counsel are becoming increasingly savvy in avoiding prosecution through the use of dummy corporations, intermediaries, and procedural techniques. Smuggling and black-market sales of banned hazardous substances also resulted from environmental legislation. In 1997 federal officials reported that the sale of contraband Freon (a refrigerant used in air conditioning systems) had become more profitable than the sale of cocaine at that time. Freon is one of the chlorofluorocarbons (CFCs), a class of chemicals known to cause ozone depletion in the atmosphere. In Mexico, which shares a two-thousand-mile border with the United States, Freon is still legal to manufacture and export, but those activities are banned in the United States. Freon, however, continues to exist in the cooling systems of many older model cars in the United States, which means a demand also exists. The State of the Environment—An Overview
9
FIGURE 1.5
Environmental Protection Agency criminal enforcement program, 2000–04 Defendants charged
Criminal investigations 500
471
482
484
400
471
360
372
425
325
400
293
300 247
Total
Total
300
200
200 100 100 0
0 2000
2001
2002
2003
2000
2004
2001
Fiscal Year (FY)
250 212
2004
$150
215
$122 146
146
100
77
$ in millions
200
Years
2003
Fines and restitution
Incarceration
150
2002 Fiscal Year (FY)
$95
$100
$62
$71 $47
$50
50 $0
0 2000
2001
2002
2003
2004
Fiscal year (FY)
2000
2001
2002
2003
2004
Fiscal year (FY)
“Criminal Investigations and Defendants Charged FY 2000–FY 2004,” and “Sentencing Results FY 2000–FY 2004,” in EPA FY 2004 End of Year Enforcement & Compliance Assurance Results, Environmental Protection Agency, Office of Enforcement and Compliance Assurance, Washington, DC, November 15, 2004, http://www.epa.gov/compliance/resources/reports/endofyear/eoy2004/fy04results.pdf (accessed August 4, 2005) SOURCE:
Another type of environmental crime gaining attention, called ‘‘ecoterrorism,’’ occurs when radical environmental groups use economic sabotage to stop what they see as threats to the environment. The Earth Liberation Front is blamed for more than six hundred attacks and nearly $43 million in property damage since the late 1990s. The group is accused of setting fire to a genetics laboratory, uprooting experimental crops, and damaging buildings. The Federal Bureau of Investigation (FBI) has named the group one of the most dangerous domestic terrorist groups in America.
THE INTERNATIONAL RESPONSE TO ENVIRONMENTAL PROBLEMS
Environmental issues have never been neatly bound by national borders. Activities taking place in one country often have an impact on the environment of other countries, if not that of the entire Earth. In fact, many of the most important aspects of environmental protection 10
The State of the Environment—An Overview
involve areas that are not located within any particular country, such as the oceans, or belong to no one, such as the atmosphere. In an attempt to deal with these issues, the international community has held a number of conferences and developed numerous declarations, agreements, and treaties. The major ones are listed in Table 1.4. A First Major Step—The Stockholm Conference In 1972 the UN met in Stockholm, Sweden, for a conference on the environment. Delegates from 113 countries met, with each reporting the state of his or her nation’s environment—forests, water, farmland, and other natural resources. The countries represented essentially fell into two groups. The industrialized countries were primarily concerned about how to protect the environment by preventing pollution and overpopulation and conserving natural resources. The less developed nations were more concerned about problems of widespread hunger, disease, and poverty they all faced. They did The Environment
FIGURE 1.6
TABLE 1.4
Environmental Protection Agency civil enforcement program, 2000–04
$40
International Convention for the Regulation of Whaling (1946) The Antarctic Treaty (1959) Convention on Wetlands of International Importance (Ramsar, Iran, 1971) United Nations Conference on the Human Environment (Stockholm, 1972) The Stockholm Declaration (1972) London Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter (1972) International Convention for the Prevention of Pollution from Ships (MARPOL, 1973/1978) Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES, 1974) Geneva Convention on Long-Range Transboundary Air Pollution (1979) The Vienna Convention for the Protection of the Ozone Layer (1985) The Montreal Protocol on Substances That Deplete the Ozone Layer (1987) The Basel Convention on the Movement of Transboundary Hazardous Wastes and Their Disposal (1989) Convention on Environmental Impact Assessment in a Transboundary Context (Espoo, Finland, 1991) United Nations Conference on Environment and Development (Earth Summit, Rio de Janeiro, 1992) The Framework Convention on Climate Change (1992) The Kyoto Protocol (1997) The Convention on Biological Diversity (1992) Agenda 21 (1992) The Rio Declaration (1992) Statement on Forest Principles (1992) The Rotterdam Convention on the Prior Informed Consent Procedures for Certain Hazardous Chemicals and Pesticides in International Trade (1998) The Stockholm Convention on Priority Organic Pollutants (2001)
$20
SOURCE:
Judicial
Administrative
Injunctive relief $6.0 $4.8
Billions
$4.5 $3.9
$4.0
$2.9 $1.6
$2.0
$0.0 FY00
FY01
FY02
FY03
FY04
Supplemental environmental projects $100
$89
$80 Millions
Major international conventions, treaties, and declarations related to the environment
$58
$56
$60
$65 $48
Created by Kim Masters Evans for Thomson Gale, 2005
$0 FY00
FY01
FY02
FY03
FY04
Total civil penalties $149
$150
$28
$126 $24 $100
$90
Millions
$84
$26
$29
$96 $24 $121
$102
$50
$64
$55
$72
$0 FY00
FY01
FY02
FY03
FY04
SOURCE: “EPA Results of Concluded Enforcement Actions FY 2000– FY 2004,” in EPA FY 2004 End of Year Enforcement & Compliance Assurance Results, Environmental Protection Agency, Office of Enforcement and Compliance Assurance, Washington, DC, November 15, 2004, http://www.epa.gov/compliance/resources/reports/ endofyear/eoy2004/fy04results.pdf (accessed August 4, 2005)
consider the environment very important, however, and were willing to protect it as long as doing so did not have a major negative economic impact on their citizens. By the end of the two-week meeting, the delegates had agreed that the human environment had to be protected, even as industrialization proceeded in the less developed countries. They established the UN EnvironThe Environment
ment Program (UNEP), which included Earthwatch, a program to monitor changes in the physical and biological resources of the Earth. The most important outcome of the conference was awareness of Earth’s ecology as a whole. For the first time in global history, the environmental problems of both rich and poor nations were put in perspective. General agreement emerged to protect natural resources, encourage family planning and population control, and protect against the negative effects of industrialization. Some Difficulties Facing International Environmental Protection Since the 1972 conference, hundreds of environmental treaties have been signed. From this, one might assume that great progress has been made, but this is not truly the case. Most experts believe that international cooperation is not keeping pace with the world’s ever-growing interdependence and the rapidly deteriorating condition of much of the environment. Carbon dioxide (CO2) levels are at record highs, water shortages exist around the world, fisheries are becoming depleted, and many scientists are warning that large numbers of species are becoming extinct. The reason for this is that, while nations agree on the fact that the environment must be safeguarded, they disagree sharply on the issue of what role each nation should play in protecting it. The State of the Environment—An Overview
11
Less developed nations are generally unwilling to alter their laws and economy to end environmentally destructive ways because a shift to environmentally friendly practices would be too expensive, they claim, for their economies to handle. Yet the richer, industrialized nations generally refuse to alter their own behavior unless the less developed nations do so as well. Their reason is not so much the cost of change rather than believing it unfair that the less developed nations want them to carry most of the burden of environmental protection. The less developed nations respond by pointing out that the industrialized nations became rich by using the very same practices they now want the less developed nations to stop using. They claim it is unfair to be expected to limit their economic development in ways that the industrialized nations themselves never would have done. This is a difficult disagreement but not an impossible one to resolve. When both sides are willing to compromise, agreements can be reached. These compromises usually require the industrialized nations to make bigger changes in their behavior, and to help the less developed nations change without too negative an impact on their economies. Even agreements like these face many obstacles. Environmental agreements seldom include a means of enforcement but rely instead on each signing country to keep its word. Faced with the actual, immediate costs of implementing environmental agreements, many countries eventually back down from their commitments. United States representatives have signed many international agreements. However, U.S. participation is not officially authorized unless and until these agreements are ratified by the U.S. Senate. As a result, as of 2005, the United States is a signatory party on many international agreements but is not yet abiding by some of them. Most international treaties related to the environment are set up so that the requirements do not become binding until a specified minimum number of parties (countries) have ratified the agreements. 1992 EARTH SUMMIT. The 1992 Earth Summit in Rio de Janeiro, Brazil, is an example of a conference where compromises were made and agreements reached but little change actually resulted. Mounting global concern for the environment prompted the UN to convene the summit meeting. Approximately 180 governments participated, making it one of the largest and most important environmental summits ever. As with prior environmental summits, the conference was split between industrialized and developing nations.
The main accomplishments of the Earth Summit were pacts on global warming and biodiversity. President 12
The State of the Environment—An Overview
George H. W. Bush attended the summit and, while there, signed the global warming treaty for the United States. President Clinton signed the biodiversity treaty in 1993. These agreements came about largely because the industrialized nations also agreed to commit 0.7% of their gross national products by 2000 to assist developing countries with compliance. Problems arose soon after the summit ended. Participating countries submitted annual reports to the fifty-threenation UN Commission on Sustainable Development (CSD), a standing body set up to implement the Rio agreements. The CSD concluded in 1994 that most countries were failing to provide the money and expertise necessary to implement the plans set at Rio. Chairman of the CSD, Klaus Toepfer of Germany, reported that the world’s efforts to finance the goals had fallen ‘‘significantly short of expectations and requirements.’’ By 1996 a number of national governments, including the United States, had prepared plans for environmental protection and submitted them to the CSD. Hundreds of municipalities had also written plans of action. The CSD once again found, however, that other issues had crowded out environmental concerns. As developed and less developed nations alike worried about the potential effects of implementing the Rio agreements, they found reasons to delay implementation and reduce funding for those programs that had been implemented. WORLD TRADE ORGANIZATION. The World Trade Organization (WTO) is an international organization whose purpose is to encourage free trade between its members. Most of the world’s nations are members. Although the WTO was officially founded in 1995, it is the result of decades of international cooperation under the General Agreement on Tariffs and Trade (GATT). The WTO continues to administer the free trade system established under GATT.
One of the primary missions of the WTO is to eliminate barriers to free trade. Doing so can have a negative effect on environmental protection, however, because laws designed to protect the environment often have the effect of restricting trade. If the WTO finds that a member nation is restricting trade in violation of GATT, other members are permitted to raise their tariffs (import taxes) on goods from that nation until the barriers to trade are eliminated. Most of the time nations quickly change their laws to eliminate barriers to trade, rather than suffer high taxes. Since it has forced many environmental laws to be weakened over the years, the WTO is greatly disliked by many environmentalists in the United States. Also, there are groups that think the organization’s power over internal U.S. affairs is too great. When the WTO met in Seattle, Washington, in 1999, tens of thousands of actiThe Environment
vists, including environmental activists, protested in the city. This massive protest succeeded in overshadowing the WTO meeting itself and drew public attention to the problems—environmental and otherwise—with free trade organizations. This was due in no small part to the violent rioting and property damage caused by some protesters. Americans are not the only ones who take issue with some of the WTO’s actions regarding the environment. For example, Europeans opposed to genetically modifying food, a procedure in widespread use in the United States by 2002, wanted restrictions placed on the sale of U.S. food in Europe, but such restrictions would violate GATT and invite retaliation by the United States. NORTH AMERICAN FREE TRADE AGREEMENT. The North American Free Trade Agreement (NAFTA), signed in 1994, is another major free trade agreement with the potential to negatively impact environmental protection in the United States. Members of NAFTA include the United States, Canada, and Mexico, and the purpose of the agreement is to eliminate trade barriers—such as most tariffs, investment restrictions, and import quotas—between these three countries. While its scope is much smaller than the WTO, NAFTA has an even greater impact on the three member countries than GATT.
A significant difference between NAFTA and GATT is that NAFTA is the first treaty of its kind ever to be accompanied by an environmental protection agreement. To discourage countries from weakening environmental standards in the name of increasing foreign trade, the United States, Canada, and Mexico signed the North American Agreement on Environmental Cooperation (NAAEC). Under NAAEC, a member country can be challenged if it or one of its states fails to enforce its environmental laws. A challenge can be brought by one of the member nations, or any interested party (such as an environmental protection group) can petition the NAAEC commission. If the commission finds a member country is showing a ‘‘persistent pattern of failure . . . to enforce its environmental law,’’ that country may be fined. If the fines are not paid, the other members are permitted to suspend NAFTA benefits in an amount not exceeding the amount of the assessed fine. Even with NAAEC, some U.S. environmentalists and state officials feared that NAFTA could result in the weakening of numerous humane laws and the reversal of thirty years of advances in animal protection and environmental cleanup. In response, Congress provided more protection for state laws and included more environmental language than in any previous trade agreement. The implementing legislation for NAFTA in the United States allows states much input and requires that they receive notification of actions that may affect them. In addition, during NAFTA discussions, the Border EnvirThe Environment
onment Cooperation Commission and the North American Development Bank were created. Independent of NAFTA itself, these agencies are intended to ensure that policy discussions are open and fairly enforced, to consider allegations that a country is not enforcing environmental laws, to help communities finance environmental infrastructures, and to resolve disputes, particularly those that cross borders. Despite all these measures designed to make sure that NAFTA does not trample on environmental protection, environmentalists still see the need for concern. They point out that U.S. laws designed to protect certain animals could be challenged as barriers to free trade under NAFTA. They also point to the increased pollution in Mexico and along its border with the United States that has resulted from the increase in trade between these two countries. PUBLIC OPINION ON THE ENVIRONMENT Quality of the Environment In March 2005 the Gallup Organization conducted its annual poll regarding environmental issues. As shown in Figure 1.7, participants were asked to rate the overall quality of the U.S. environment as excellent, good, only fair, or poor. Only 4% of those asked gave the environment an excellent rating. Another 37% rated the environment in good condition, while 48% considered it in fair condition and 10% rated it in poor condition. In general the breakdown is similar to that obtained in polls dating back to 2001.
Another question from Gallup’s 2005 Environment poll asked if people believed the quality of the environment as a whole was getting better, getting worse, or staying the same. In 2005 a majority of respondents (63%) expressed the pessimistic view that the environment is getting worse. Another 29% believed that the environment is improving, and 6% thought it is about the same. This breakdown has remained relatively constant since the question was first asked in 2001. Grading the Environmental Movement As part of its 2005 poll, Gallup asked people to rate the overall performance of the environmental movement. As shown in Figure 1.8 a majority of those asked (69%) felt that the movement had done more good than harm, while 28% thought it had done more harm than good. Environmental Protection Efforts Gallup also asked poll participants to rate their level of trust in the ability of various entities to protect the quality of the nation’s environment. These entities are listed below along with the percentage of respondents expressing a ‘‘great deal’’ of trust in them.
• Local environmental organizations (26%) • National environmental organizations (25%) The State of the Environment—An Overview
13
FIGURE 1.7
FIGURE 1.8
Public opinion on the quality of the environment, March 2005 “HOW WOULD YOU RATE THE OVERALL QUALITY OF THE ENVIRONMENT IN THIS COUNTRY TODAY—AS EXCELLENT, GOOD, ONLY FAIR, OR POOR?”
No opinion 1%
Public opinion on the success of the environmental movement, April 2005 “ALL THINGS CONSIDERED, DO YOU THINK THE ENVIRONMENTAL MOVEMENT IN THIS NATION HAS DONE MORE GOOD THAN HARM, OR MORE HARM THAN GOOD?”
Excellent 4%
No opinion 3%
Poor 10%
Good 37% Only fair 48%
SOURCE: Adapted from “How would you rate the overall quality of the environment in this country today—as excellent, good, only fair, or poor?” in Environment, The Gallup Organization, Princeton, NJ, April 2005, http://www.gallup.com/poll/content/default.aspx?ci⫽1615 (accessed August 4, 2005). Copyright © 2005 The Gallup Organization. Reproduced by permission of The Gallup Organization.
• Federal environmental agencies, like the EPA (22%)
More harm than good 28% More good than harm 69%
SOURCE: Adapted from “All things considered, do you think the environmental movement in this nation has done more good than harm, or more harm than good? Would you say it has done—definitely more good than harm, probably more good than harm, probably more harm than good, or definitely more harm than good?” in Environment, The Gallup Organization, Princeton, NJ, April 2005, http://www.gallup .com/poll/content/default.aspx?ci⫽1615 (accessed August 4, 2005). Copyright © 2005 The Gallup Organization. Reproduced by permission of The Gallup Organization.
• State environmental agencies (16%) • Small businesses (15%) • The Democratic Party (15%) • Local government agencies (11%) • The U.S. Congress (11%)
environmental policies at about the same level as they had been historically. Another 40% felt that the administration had weakened those policies, and 5% thought that policies had been strengthened.
• The Republican Party (9%)
Personal Participation
• Large corporations (7%)
Despite an apparent dissatisfaction with government actions regarding the environment, there is no indication that Americans feel more compelled to become actively involved in environmental issues. Only 16% of the people polled considered themselves active participants in the environmental movement. Far more (49%) were sympathetic to the movement but not active. Another 28% expressed neutral feelings about it and 5% were unsympathetic. These numbers are quite similar to those obtained in Gallup environment polls dating back to the year 2000.
Rating the Government’s Role
In general, the results from Gallup’s 2005 Environment poll indicate dissatisfaction with the government’s role in protecting the environment. In 2005 a majority of those asked (58%) felt that the government was doing too little in this regard. More than a third (34%) thought the government was doing about the right amount, and 5% believed the government was doing too much. The percentage of people who believe the government is doing too little to protect the environment has decreased since 1992 when 68% expressed this view. Slightly more than half of those asked (52%) said that the Bush administration was maintaining the nation’s 14
The State of the Environment—An Overview
In 2005 only 7% of those asked belonged to any large national or international environmental organizations. Slightly more respondents (12%) belonged to environmental groups or organizations in their local community, region, or state. The Environment
Competing Interests: Environment, Energy, and Economy For many years the Gallup Organization has polled people about which should take priority: the environment or economic growth. The vast majority of polls conducted between 1984 and 2000 showed strong support for the environment even at the risk of curbing economic growth. In all of these polls at least 58% of the people asked agreed with this view. The tide began to turn during the early 2000s as economic growth became a higher priority.
The March 2005 poll showed that 53% of those asked believed that environmental protection should be given priority even if it risked curbing economic growth. More than one third (36%) felt that economic growth should be given priority even if it meant that the environment would suffer to some extent. According to Gallup, a small percentage (7%) advocated giving equal priority to environmental protection and economic growth. The percentage breakdown was very similar for a poll question regarding development of U.S. energy supplies versus environmental protection. Gallup found in 2005 that 52% of respondents felt that protection of the environment should have priority, even if it might limit the amount of energy supplies, such as oil, coal, and gas, that the nation could produce. Another 39% of people thought that development of energy supplies should have priority over the environment. A small percentage (4%) indicated that the two should have equal priority. Americans Rank Their Concerns In March 2005 Gallup asked poll participants to rate their level of worry regarding twelve social and political issues. (See Figure 1.9.) The availability and affordability of healthcare garnered the most concern with 60% of respondents expressing a great deal of worry about it. It was followed by social security, crime and violence, drug use, terrorism, energy, the economy, and hunger and homelessness. The environment ranked ninth with 35% of those asked expressing a great deal of worry about it. Concern was greatest among people aged eighteen to twenty-nine years and those that classified themselves as ‘‘nonwhite.’’
In another question, poll respondents were asked to project what is likely to be the most important problem facing the nation in twenty-five years. The environment ranked third in this poll behind Social Security and the economy. In Gallup’s 2002 and 2003 environmental polls they asked participants to rate various environmental issues in regard to the amount of concern they feel about them: a great deal, a fair amount, a little, or none. The ten issues assessed were as follows: • Acid rain • Air pollution The Environment
FIGURE 1.9
Public opinion on the problems facing the country, March 2005 “NEXT I’M GOING TO READ A LIST OF PROBLEMS FACING THE COUNTRY. FOR EACH ONE, PLEASE TELL ME IF YOU PERSONALLY WORRY ABOUT THIS PROBLEM A GREAT DEAL, A FAIR AMOUNT, ONLY A LITTLE, OR NOT AT ALL? FIRST, HOW MUCH DO YOU PERSONALLY WORRY ABOUT…?” Percentage saying “great deal” The availability and affordability of healthcare
60%
Social security
48% 46%
Crime and violence Drug use
42%
The possibility of future terrorist attacks in the U.S.
41%
The availability and affordability of energy
39% 38%
The economy
37%
Hunger and homelessness The quality of the environment
35%
Illegal immigration
33% 27%
Unemployment Race relations
16%
SOURCE: Rick Blizzard, “Concern About Healthcare in the United States,” in Healthcare Concerns Whites, Life-and-Death Matter for Blacks, Gallup Corporation, Princeton, NJ, April 12, 2005, http:// www.gallup.com/poll/content/print.aspx?ci⫽15835 (accessed August 4, 2005). Copyright © 2005 The Gallup Organization. Reproduced by permission of The Gallup Organization.
• Contamination of soil and water by toxic waste • Damage to the Earth’s ozone layer • Extinction of plant and animal species • Greenhouse effect (global warming) • Loss of tropical rain forests • Maintenance of the nation’s supply of fresh water for household needs • Pollution of drinking water • Pollution of rivers, lakes, and reservoirs Pollsters found that pollution of drinking water had the highest percentage of respondents expressing a great deal of concern. (See Figure 1.10.) It topped the list with 53%, followed by pollution of rivers, lakes, and reservoirs with 48%, and contamination of soil and water by toxic waste, also with 48%. In general, water-related issues garnered the most amount of concern. The State of the Environment—An Overview
15
grants to more than twenty-seven hundred such projects at a cost of more than $32 million.
FIGURE 1.10
Americans expressing a great deal of concern about environmental problems, 2002–03 I’M GOING TO READ YOU A LIST OF ENVIRONMENTAL PROBLEMS. AS I READ EACH ONE, PLEASE TELL ME IF YOU PERSONALLY WORRY ABOUT THIS PROBLEM A GREAT DEAL, A FAIR AMOUNT, ONLY A LITTLE, OR NOT AT ALL.
Percentage saying “a great deal”
53%
Pollution of drinking water Pollution of rivers, lakes, and reservoirs
48%
Contamination of soil and water by toxic waste
48%
Maintenance of the nation’s supply of fresh water for household needs
47% 39%
Air pollution Extinction of plant and animal species
36% 35%
The loss of tropical rain forests Damage to the Earth’s ozone layer
33%
The “greenhouse effect” or global warming Acid rain
26% 20%
SOURCE: Darren K. Carlson, “Concern About Environmental Problems,” in Water Worries Deluge Environmental Concerns, The Gallup Organization, Princeton, NJ, April 6, 2004, http://www.gallup.com/ content/print.aspx?ci⫽11227 (accessed August 4, 2005). Copyright © 2004 by The Gallup Organization. Reproduced by permission of The Gallup Organization.
How Reliable Are Polls on Environmental Issues? Some experts suggest that opinion polls are an unreliable guide to how voters actually feel about environmental issues. Although polls of Americans indicate that concern for environmental issues is substantial, this same level of concern does not manifest itself when it comes to actual voting and purchasing decisions. Some observers suggest that people often claim in polls that they are interested in environmental issues because they are trying to give the pollster the answer that he or she wants to hear. In other words, they are giving what they think is the ‘‘right’’ answer. In actuality, respondents may be more interested in other issues and, in the voting booth, may vote other than their poll answers would indicate. ENVIRONMENTAL EDUCATION Teaching about the Environment in Schools Many states require schools to incorporate environmental concepts, such as ecology, conservation, and environmental law, into many subjects at all grade levels. Some even require special training in environmentalism for teachers. Between 1992 and 2003 the EPA gave 16
Although this mandating of environmental education pleases environmentalists, and studies have shown that most Americans support environmental education, some people have protested. Critics claim that most environmental education in the schools is based on flawed information, biased presentations, and questionable objectives. Critics also say it leads to brainwashing and pushing a regulatory mind-set on students. Some critics contend that, at worst, impressionable children are being trained to believe that the environment is in immediate danger of catastrophe because of consumption, economic growth, and free market capitalism.
The State of the Environment—An Overview
Lacking Basic Knowledge In May 2004 the National Environmental Education and Training Foundation (NEETF), a private nonprofit organization, published a report titled ‘‘Understanding Environmental Literacy in America: And Making It a Reality’’ (http://www.neetf.org/roper/ELR.pdf). The report summarizes the NEETF’s findings on the depth of knowledge of environmental issues by American students and adults. It is based on polls and studies conducted by a variety of organizations, including the NEETF, Roper Starch Worldwide, and National Geographic.
The report notes that overall knowledge among adults regarding ‘‘simple’’ environmental topics was generally good. However, the author states that ‘‘the average adult American, regardless of age, income or level of education, mostly fails to grasp essential aspects of environmental science, important cause/effect relationships or even basic, but multi-step, concepts, such as runoff pollution, power generation and fuel use, water flow patterns or ecosystem dynamics.’’ Researchers found that media sources, such as television and newspapers, were the primary source of environmental information for both children and adults. According to the NEETF, the media’s influence is powerful, even though most media outlets provide ‘‘superficial information’’ that ‘‘sometimes confuses the public and seldom ever truly educates.’’ The public’s reliance on the media for environmental education is blamed for the persistence of commonly held but mistaken beliefs that the NEETF calls environmental myths, such as the idea that diapers fill landfills (when in reality paper products account for 50 times more waste). The NEETF report estimates that 80% of Americans believe in incorrect and outdated environmental myths. Less that one third (32%) demonstrated ‘‘basic awareness’’ of environmental topics. Only 12% of those tested passed a ‘‘basic’’ quiz on energy topics. The NEETF concludes that environmental literacy is very poor in the United States due to ‘‘shallow, disorganized and inadequate education on the environment.’’ The Environment
CHAPTER 2
AIR QUALITY
THE AIR PEOPLE BREATHE According to the Environmental Protection Agency (EPA), the average person breathes in more than three thousand gallons of air each day. Because air is so essential to life, it is important that it be free of pollutants. Throughout the world poor air quality contributes to hundreds of thousands of deaths and diseases each year, not to mention dying forests and lakes and the corrosion of stone buildings and monuments. Air quality is also important to quality of life and recreation because air pollution causes haze that decreases visibility during outdoor activities.
Air pollutants are generated by natural and anthropogenic (human-related) sources. Fossil fuels and chemicals have played a major role in society’s pursuit of economic growth and higher standards of living. However, burning fossil fuels and releasing toxic chemicals into the air alter Earth’s chemistry and can threaten the very air on which life depends. THE HISTORY OF AIR POLLUTION LEGISLATION Air pollution from the burning of fossil fuels was a problem in urban areas of England as long ago as the fourteenth century. In 1307 King Edward I banned the burning of coal in London ‘‘to avoid the sulfurous smoke’’ and commanded Londoners to burn wood instead. The ban was short-lived, however, as a wood shortage forced the city to switch back to coal. Historians record that future British monarchs also tried unsuccessfully to curtail the use of coal to reduce air pollution.
The onset of the Industrial Revolution in the late 1700s was accompanied by a tremendous increase in the use of fossil fuels and air pollution in England and the United States. Major U.S. cities began passing smoke ordinances during the late 1800s. Air pollution control remained a local issue for several more decades. The Environment
By the late 1940s smog had become a serious problem in many urban areas. Extensive industrial growth during World War II, a boom in car ownership, and unregulated outdoor burning were the primary culprits. Los Angeles and other large U.S. cities suffered from ‘‘smog attacks’’ during hot summer months. In 1952 London experienced an episode of smog so severe that thousands of people prematurely died from respiratory illnesses aggravated by poor air quality. The incident was a wake-up call for many governments. Air pollution legislation was quickly passed in England and across Europe. U.S. Air Pollution Legislation In the United States concerns about smog led to passage of the Air Pollution Control Act of 1955. It provided grants to public health agencies to research the threats posed to human health by air pollution. In 1963 the first Clean Air Act (CAA) was passed. It set aside even more grant money for research and data collection and encouraged development of emissions standards for major sources of pollution. The act was amended several times through the remainder of the decade to expand research priorities and local air pollution control agencies and set national emission standards for some sources. THE CLEAN AIR ACT OF 1970. In 1970 the CAA received a major overhaul. It required the newly established EPA to set National Ambient Air Quality Standards (NAAQS) for major pollutants. These standards are divided into two classes:
• Primary Standards are designed to protect public health, with special focus on so-called ‘‘sensitive’’ populations including children, the elderly, and people with chronic respiratory problems, such as asthma. • Secondary Standards are designed to protect the overall welfare of the public by reducing air pollution that impairs visibility and damages resources, such as crops, forests, animals, monuments, and buildings. 17
State environmental agencies have to prepare State Implementation Plans to show how they plan to achieve compliance with the NAAQS. Counties that meet NAAQS for a particular pollutant are called attainment areas for that pollutant; counties that do not meet NAAQS are called nonattainment areas. The revised CAA also required the setting of National Emissions Standards for Hazardous Air Pollutants (NESHAPs) and resulted in New Source Performance Standards (NSPS). These are technology-based standards that apply when certain types of facilities are first constructed or undergo major modifications. Although NSPS are set by the EPA, state governments are responsible for enforcing them. In 1977 the CAA was amended again. The major change was expansion of a program called Prevention of Significant Deterioration (PSD). The PSD program is designed to ensure that new facilities built in attainment areas do not significantly degrade the air quality. THE CLEAN AIR ACT AMENDMENTS OF 1990. In 1990 the CAA was substantially revised to better address three issues of growing concern: acid rain, urban air pollution (particularly smog), and emissions of toxic air pollutants. In addition, a national permits program was established, and enforcement and compliance procedures were strengthened. The Clean Air Act Amendments of 1990 (CAAA; PL 101–549) included new and innovative approaches to air pollution legislation. Market-based programs allow businesses more choices in how they achieve pollution control goals. Economic incentives were also included to reduce the reliance on regulations to obtain certain goals. An outline of the major sections of the CAA is included in Table 2.1.
In 2002 President George W. Bush proposed his Clear Skies initiative to set caps on emissions of sulfur dioxide, nitrogen oxides, and mercury from power plants. Although Clear Skies legislation was introduced in Congress in 2002 and 2003, it was not passed. A revised version of the Clear Skies Act was introduced in January 2005 but was still under consideration as of July 2005. According to the EPA Web site, the legislation would cut power plant emissions of the targeted pollutants by 70% and eliminate thirty-five million more tons of these pollutants over the next decade than would be expected under the existing Clean Air Act. THE CLEAR SKIES CONTROVERSY.
However, environmental groups are opposed to the proposed Clear Skies Act, because it would institute a ‘‘cap-and-trade’’ system. This would set overall caps on emissions but allow utility companies operating below emission limits to sell ‘‘credits’’ to other companies having trouble meeting the limits. Although a similar system is used to control emissions that cause acid rain, critics believe that this approach is not appropriate for more potent air 18
Air Quality
TABLE 2.1
Clean Air Act list of titles • • • • • •
Title I—Air Pollution Prevention And Control Title II—Emission Standards For Moving Sources Title III—General Title IV—Acid Deposition Control Title V—Permits Title VI—Stratospheric Ozone Protection
“Clean Air Act Table of Contents,” in Clean Air Act, U.S. Environmental Protection Agency, Washington, DC, July 2005, http://www .epa.gov/air/oaq_caa.html/ (accessed August 4, 2005) SOURCE:
pollutants, such as mercury. They fear that the cap-andtrade system would allow utility plants in some areas to release unacceptably high levels of these pollutants. WHAT ARE THE MAJOR AIR POLLUTANTS? The CAAA of 1990 established NAAQS for six major air pollutants:
• carbon monoxide (CO) • lead (Pb) • nitrogen oxides (NOx) • ozone (O3) • particulate matter (PM) • sulfur oxides (SOx) These are called the priority or criteria pollutants and are identified as serious threats to human health. The CAAA required states to develop plans to implement and maintain the NAAQS. The states can have stricter rules than the federal program but not more lenient ones. In addition, regulations developed under the CAAA cover nearly two hundred chemical substances classified as hazardous air pollutants (HAPs). HAPs are also called air toxics. The EPA has documented air pollution trends in the United States annually since 1973. As of June 2005 the latest complete report available presents data through 2002. Preliminary data for 2003 and 2004 are available on the EPA website at http://www.epa.gov/airtrends/ 2005/econ-emissions.html. The EPA reports two kinds of trends for priority pollutants: emissions and air quality concentrations. Emissions are calculated estimates of the total tonnage of these pollutants released into the air annually. Air quality concentrations are based on data collected at thousands of monitoring sites around the country. The EPA maintains a database called the National Emission Inventory that characterizes the emissions of air pollutants in the United States based on data input from state and local agencies. From 1970 to 2004 total emissions of the six priority pollutants decreased by 54%. This occurred even as the The Environment
TABLE 2.2
EPA estimates of national air pollutant emissions, 1970–2004 Millions of tons per year
Carbon monoxide (CO) Nitrogen oxides (NOx)c Particulate matter (PM)d PM10 PM2.5e Sulfur dioxide (SO2) Volatile organic compounds (VOC) Leadf Totalsg
1970
1975
1980
1985a
1990
1995
2000a
2004b
197.3 26.9
184.0 26.4
177.8 27.1
169.6 25.8
143.6 25.2
120.0 24.7
102.4 22.3
87.2 18.8
12.21 NA 31.2
7.0 NA 28.0
6.2 NA 25.9
3.6 NA 23.3
3.2 2.3 23.1
3.1 2.2 18.6
2.3 1.8 16.3
2.5 1.9 15.2
33.7 0.221
30.2 0.16
30.1 0.074
26.9 0.022
23.1 0.005
21.6 0.004
16.9 0.003
15.0 0.003
301.5
275.8
267.2
249.2
218.2
188.0
160.2
138.7
a
In 1985 and 1996 EPA refined its methods for estimating emissions. Between 1970 and 1975, EPA revised its methods for estimating particulate matter emissions. b The estimates for 2004 are preliminary. c NOx estimates prior to 1990 include emissions from fires. Fires would represent a small percentage of the NOx emissions. d PM estimates do not include condensable PM, or the majority of PM2.5 that is formed in the atmosphere from ‘precursor’ gases such as SO2 and NOx. e EPA has not estimated PM2.5 emissions prior to 1990. f The 1999 estimate for lead is used to represent 2000 and 2003 because lead estimates do not exist for these years. g PM2.5 emissions are not added when calculating the total because they are included in the PM10 estimate.
“National Air Pollutant Emissions Estimates (Fires and Dust Excluded) for Major Pollutants,” in Air Emissions Trends—Continued Progress Through 2004, U.S. Environmental Protection Agency, Washington, DC, June 2005, http://www.epa.gov/airtrends/econ-emissions.html (accessed August 4, 2005) SOURCE:
United States experienced massive increases in gross domestic product and vehicle miles traveled and moderate increases in overall energy consumption and population. Table 2.2 compares emissions of the principal air pollutants for various years between 1970 and 2004. The table shows that emissions have declined for each pollutant. However, there is still much work to be done to clear the air. The EPA estimates that during 2004 nearly 140 million tons of air pollutants were emitted in the United States.
FIGURE 2.1
Carbon monoxide emissions, 1983–2002
In 2004 approximately eighty-seven million tons of CO were emitted into the air. As shown in Table 2.2, CO emissions have decreased by 56% since 1970. Transportation has historically been the largest source of CO emissions. Figure 2.1 shows the primary sources of CO emissions from 1983 to 2002. In 2003 highway vehicles accounted for 55% of known CO emissions, and off-highway vehicles, such as bulldozers and forklifts, accounted for 23%. Fires produced another 12% of CO emissions. From 1993 through 2003 forest fires (planned and unplanned) have contributed 5–14% of the nation’s carbon monoxide emissions each year. Nontransportation fuel combustion, industrial processes, and miscellaneous other sources are also minor contributors of CO emissions (http://www.epa.gov/airtrends/2005/pdfs/ CONational.pdf ). EMISSIONS AND SOURCES.
Air quality concentrations of CO from 1983 to 2002 are shown in Figure 2.2 based on monitorAIR QUALITY.
The Environment
160,000 Thousand short tons
Carbon monoxide (CO) is a colorless, odorless gas created when the carbon in certain fuels is not burned completely. These fuels include coal, natural gas, oil, gasoline, and wood.
Transportation
Industrial processes
Fires
In 1985, the Environmental Protection Agency refined its methods for estimating emissions
200,000 180,000
Carbon Monoxide
Fuel combustion
Fire emissions not available for 2002
140,000 120,000 100,000 80,000 60,000 40,000 20,000 0
83
85
93 94 95 96 97 98 99 00 01 02 1983–02: 41% decrease 1993–02: 21% decrease
SOURCE: Adapted from “CO Emissions, 1983–2002,” in Latest Findings on National Air Quality: 2002 Status and Trends, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, August 2003
ing data from 205 sites around the country. Over this time period CO concentrations decreased by 65%. In 2002 the average measured CO concentration at the monitoring sites was just under three parts per million (three parts CO per million parts of air). Despite these improvements there are still areas of the country with air quality concentrations of CO that are ‘‘persistently’’ above the NAAQS. These nonattainment Air Quality
19
FIGURE 2.2
FIGURE 2.3
Carbon monoxide air quality concentrations, 1983–2002
Lead emissions, 1982–2002
[Based on annual second maximum 8-hour average] Fuel combustion
Industrial processes
Transportation
205 sites
14
80,000
90% of sites have concentrations below this line
12 10
In 1985, the Environmental Protection Agency refined its methods for estimating emissions.
NAAQS*
60,000
8 Short tons
Concentration, parts per million
16
6 Average 4 2
10% of sites have concentrations below this line
0
40,000
20,000
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 0
1983–02: 65% decrease 1993–02: 42% decrease
82
85
92 93 94 95 96 97 98 99 00 01 02 1982–02: 93% decrease 1993–02: 5% decrease
*National Ambient Air Quality Standards
“CO Air Quality, 1983–2002,” in Latest Findings on National Air Quality: 2002 Status and Trends, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, August 2003 SOURCE:
ADVERSE HEALTH EFFECTS. CO is a dangerous gas that enters a person’s bloodstream through the lungs. It reduces the ability of blood to carry oxygen to the body’s cells, organs, and tissues. The health danger is highest for people suffering from cardiovascular diseases.
Lead Lead is a metal that can enter the atmosphere via combustion or industrial processing of lead-containing materials.
FIGURE 2.4
Lead air quality, 1983–2002 [Based on annual maximum quarterly average]
1.6
42 sites NAAQS*
1.4 Concentration, g/m3
areas are designated as having ‘‘serious’’ or ‘‘moderate’’ CO pollution depending on the air quality concentrations. As of April 2005 Las Vegas, Los Angeles, and Spokane, Washington, were classified serious CO nonattainment areas.
“Lead Emissions, 1982–2002,” in Latest Findings on National Air Quality: 2002 Status and Trends, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, August 2003 SOURCE:
1.2
90% of sites have concentrations below this line
1.0 0.8
Average
0.6 0.4
10% of sites have concentrations below this line
0.2 0.0 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 1983–02: 94% decrease 1993–02: 57% decrease
The EPA reports that three thousand tons of lead were emitted into the air during 2004. (See Table 2.2.) Lead emissions declined by 99% between 1970 and 2004. Prior to 1985 the major source of lead emissions in the United States was the leaded gasoline used in automobiles. Conversion to unleaded gasoline produced a dramatic reduction in lead emissions, as shown in Figure 2.3. As a result, transportation has virtually been eliminated as a source of lead emissions. Industrial processes (chiefly metals smelting and battery manufacturing) are responsible for the bulk of lead emissions.
attainment areas in the country as of April 2005. These locations are East Helena, Montana, and Herculaneum, Missouri.
AIR QUALITY. Air quality concentrations of lead based on monitoring data from forty-two sites from 1983 to 2002 are shown in Figure 2.4. Despite great progress in lead reduction, there are still two lead non-
ADVERSE HEALTH EFFECTS. Lead is a particularly dangerous pollutant because it accumulates in the blood, bones, and soft tissues of the body. It can adversely affect the nervous system, kidneys, liver, and other organs.
EMISSIONS AND SOURCES.
20
Air Quality
*National Ambient Air Quality Standards
“Lead Air Quality, 1983–2002,” in Latest Findings on National Air Quality: 2002 Status and Trends, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, August 2003 SOURCE:
The Environment
FIGURE 2.5
FIGURE 2.6
Nitrogen oxide emissions, 1983–2002
Nitrogen oxides air quality, 1983–2002 [Based on annual arithmetic average] Industrial processes
Transportation
Miscellaneous
In 1985, the Environmental Protection Agency refined its methods for estimating emissions.
30,000
Thousand short tons
25,000 20,000 15,000
0.06 Concentration, parts per million
Fuel combustion
0.05
125 sites 90% of sites have concentrations below this line
NAAQS*
0.04 0.03
Average
0.02 0.01 10% of sites have concentrations below this line 0.0
10,000
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 1983–02: 21% decrease 1993–02: 11% decrease
5,000 0 83
85
93 94 95 96 97 98 99 00 01 02 1983–02: 15% decrease 1993–02: 12% decrease
“NO5 Emissions, 1983–2002,” in Latest Findings on National Air Quality: 2002 Status and Trends, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, August 2003 SOURCE:
Excessive concentrations are associated with neurological impairments, mental retardation, and behavioral disorders. Even low doses of lead can damage the brains and nervous systems of fetuses and young children. Atmospheric lead that falls onto vegetation poses an ingestion hazard to humans and animals. Nitrogen Dioxide Nitrogen dioxide (NO2) is a reddish-brown gas that forms in the atmosphere when nitrogen oxide (NO) is oxidized. Inhalation of even low concentrations of NO2 for short time periods can be harmful to the human body’s breathing functions. Longer exposures are considered damaging to the lungs and may cause people to be more susceptible to certain respiratory problems, such as infections.
The chemical formula NOx is used collectively to describe NO, NO2, and other nitrogen oxides. EMISSIONS AND SOURCES. As shown in Table 2.2 there were 18.8 million tons of NOx emitted during 2004. Emissions have decreased by 30% since 1970. Most of this improvement occurred during the late 1990s and early 2000s as shown in Figure 2.5.
NO2 primarily comes from burning fuels such as gasoline, natural gas, coal, and oil. The exhaust from highway vehicles is the major source of NOx, accounting for 36% of emissions during 2003. Fuel combustion in power plants, homes, and businesses accounted for 22% of NOx emissions. Other major sources include off-highThe Environment
*National Ambient Air Quality Standards
“NOx Air Quality, 1983–2002,” in Latest Findings on National Air Quality: 2002 Status and Trends, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, August 2003
SOURCE:
way vehicles (20%) and fuel combustion at industrial facilities (13%). Industrial processes and miscellaneous sources were minor contributors. The EPA notes that despite the overall decrease in NOx emissions in this country, emissions from off-highway engines increased dramatically between 1970 and 2004. These are engines in tractors, lawn mowers, construction and industrial equipment, off-road recreational vehicles, boats, trains, and airplanes. In July 2005 the EPA adopted amendments to its nonroad and highway diesel fuel regulations. NO2 is a major precursor of smog and also contributes to acid rain and haze. It can also undergo reactions in the air that lead to the formation of particulate matter and ozone. Figure 2.6 illustrates the air quality concentrations of NO2 based on monitoring data from 125 sites around the country from 1983 to 2002. Over this time period NO2 concentrations decreased by 21%. In 2002 the average measured NO2 concentration at the monitoring sites was approximately 0.02 parts per million. As of April 2005 all U.S. counties attained the EPA standards for NO2 air quality. AIR QUALITY.
NOx reacts with ammonia and water droplets in the atmosphere to form nitric acid and other chemicals that are potentially harmful to human health. Inhalation of these particles can interfere with respiratory processes and damage lung tissue. Particles inhaled deeply into the lungs can cause or aggravate respiratory conditions such as bronchitis and emphysema. ADVERSE HEALTH EFFECTS.
Air Quality
21
EMISSIONS AND SOURCES. Unlike other air pollutants, ground-level ozone is not emitted directly into the air. It forms mostly on sunny, hot days due to complex chemical reactions that take place when the atmosphere contains other pollutants, primarily volatile organic compounds (VOCs) and nitrogen oxides. Such pollutants are called ozone precursors because their presence in the atmosphere leads to ozone creation.
VOCs are carbon-containing chemicals that easily become vapors or gases. Paint thinners, degreasers, and other solvents contain a great number of VOCs, which are also released from burning fuels such as coal, natural gas, gasoline, and wood. VOC emissions dropped by 55% from 1970 to 2004. (See Table 2.2.) Most of the decline occurred in industrial processing and transportation sources. In 2003 solvents and highway vehicles each accounted for 28% of the emissions. Off-highway vehicles produced another 16% of emissions. All other sources were minor contributors. Ozone has different health and environmental effects depending on the time of exposure. The EPA monitors average eight-hour and one-hour ozone levels and sets different standards for each. Ozone concentrations can vary greatly from year to year depending on the emissions of ozone precursors and weather conditions. AIR QUALITY.
As shown in Figure 2.7, the average national ozone concentration, based on an eight-hour average, decreased by 21% between 1980 and 2003. Between 1980 and 2003 the average one-hour concentration decreased by 29%. (See Figure 2.8.) As of April 2005 there were dozens of locations around the country classified as nonattainment for ozone air quality. Two areas were classified as ‘‘extreme’’ nonattainment for the one-hour ozone standard: Los Angeles and the San Joaquin Valley in California. Locations classified as ‘‘severe’’ nonattainment are located in and around Chicago, Houston, Milwaukee, New York City, Atlanta, Baltimore, Baton Rouge, Philadelphia, Sacramento, Washington, D.C., Ventura County, California, and southeastern desert areas of California. The Los Angeles area was the only location classified as ‘‘severe’’ 22
Air Quality
FIGURE 2.7
Trends in eight-hour ozone air quality, 1980–2003
Concentration, parts per million
0.20
155 monitoring sites 90th percentile
0.15 National standard 0.10
0.05
Mean
10th percentile
0.00 80
82
84
86
88
90
92
94
96
98
00
02
1980–2003: ⴚ21%
“Figure 8.8-Hour Ozone Air Quality Trend, 1980–2003, Based on 3-Year Rolling Averages of Annual Fourth Highest Daily Maximum 8-Hour Ozone Concentrations,” in The Ozone Report: Measuring Progress through 2003, U.S. Environmental Protection Agency, Washington, DC, April 2004, http://www.epa.gov/air/airtrends/pdfs/ 2003ozonereport.pdf (accessed August 4, 2005) SOURCE:
FIGURE 2.8
Trends in one-hour ozone air quality, 1980–2003 155 monitoring sites 0.20 Concentration, parts per million
Ozone Ozone is a gas naturally present in Earth’s upper atmosphere. Approximately 90% of Earth’s ozone lies in the stratosphere at altitudes greater than about twenty miles. Ozone molecules at this level absorb ultraviolet (UV) radiation from the sun and prevent it from reaching the ground. Thus, stratospheric ozone (the ‘‘ozone layer’’) is good for the environment. Tropospheric (or ground-level) ozone, on the other hand, is a potent air pollutant with serious health consequences. It is the most complex, pervasive, and difficult to control of the six priority pollutants.
National standard 90th percentile
0.15
0.10 Mean
10th percentile 0.05 0.00 80
82
84
86
88
90
92
94
96
98
00
02
1980–2003: ⴚ29% SOURCE: “Figure 6. One-Hour Ozone Air Quality Trend, 1980–2003, Based on Running Fourth Highest Daily Maximum 1-Hour Ozone Value Over 3 Years,” in The Ozone Report: Measuring Progress Through 2003, U.S. Environmental Protection Agency, Washington, DC, April 2004, http://www.epa.gov/air/airtrends/pdfs/ 2003ozonereport.pdf (accessed August 4, 2005)
nonattainment for the eight-hour ozone standard. These exceedances affected more than one hundred million people. Ozone has, by far, the largest nonattainment area of any of the six priority pollutants. OZONE CONTRIBUTES TO SMOG. Ground-level ozone is the primary component in smog. Smog, a word made up by combining ‘‘smoke’’ and ‘‘fog,’’ is probably the most well-known form of air pollution. It retards crop and tree growth, impairs health, and limits visibility. When
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temperature inversions occur (the warm air stays near the ground instead of rising) and winds are calm, such as during the summer, smog may hang over a huge area for days at a time. As traffic and other pollution sources add more pollutants to the air, the smog gets worse. Wind often blows smog-forming pollutants away from their sources; this is why smog frequently can be more serious miles away from where the pollutants were created. Most people associate dirty air with cities and the areas around them. There is good reason for this, because some of the worst smog in the country occurs in such urban areas as Los Angeles, California—a city known for its air quality problems. In a major industrial nation such as the United States, however, smog is not limited just to cities. The Great Smoky Mountains, located in western North Carolina and eastern Tennessee, are seeing more air pollution. Harmful emissions from various coal-burning facilities located outside the mountain range, as well as pollution from motor vehicles, are damaging the mountains’ environment. Ground-level ozone is harmful to ecosystems, particularly vegetation. Ozone exposure reduces forest yields by stunting the growth of seedlings and increasing stresses on trees. Such damage can take years to become evident. Between 1993 and 2002 the EPA monitored ozone levels based on eight-hour average concentrations at twenty-eight national parks around the country. The results indicated that ozone levels increased at eighteen of the parks, remained unchanged at four other parks, and decreased at six parks. ADVERSE HEALTH EFFECTS. Even the smallest amounts of ozone can cause breathing difficulties. Ozone exposure can cause serious problems with lung functions, leading to infections, chest pain, and coughing. According to the EPA, ozone exposure is linked with increased emergency room visits and hospital admissions due to such respiratory problems as lung inflammation and asthma. Ozone causes or aggravates these problems, particularly in people working outdoors, the elderly, and children. Children are especially susceptible to the harmful effects of ozone because they spend a great deal of time outside and because their lungs are still developing.
According to the Centers for Disease Control and Prevention (CDC), the percentage of American children with asthma more than doubled between 1980 and 2003. In 1980 approximately 3.7% of all children age seventeen and younger suffered from asthma. By 2003 this figure had climbed to 9%. In general asthma levels are greater among children that live in inner cities, areas also prone to higher concentrations of ozone, smog, and other air pollutants. Long-term exposure of any age group to moderate levels of ozone is thought to cause irreversible lung damage due to premature aging of the tissues. The Environment
TABLE 2.3
Air Quality Index (AQI): Ozone Index values
Level of health concern
0–50 51–100*
Good Moderate
101–150
Unhealthy for sensitive groups
151–200
Unhealthy
201–300
Very unhealthy
301–500
Hazardous
Cautionary statements None Unusually sensitive people should consider limiting prolonged outdoor exertion. Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion. Active children and adults, and people with respiratory disease, such as asthma, should avoid prolonged outdoor exertion; everyone else, especially children, should limit outdoor exertion. Active children and adults, and people with respiratory disease, such as asthma, should avoid all outdoor exertion; everyone else, especially children, should limit outdoor exertion. Everyone should avoid all outdoor exertion.
*Generally, an AQI of 100 for ozone corresponds to an ozone level of 0.08 parts per million (averaged over 8 hours).
“Air Quality Index (AQI): Ozone,” in Air Quality Index—A Guide to Air Quality and Your Health, U.S. Environmental Protection Agency, Office of Air and Radiation, Washington, DC, June 2000 SOURCE:
The EPA maintains an Air Quality Index (AQI) as a means for warning the public when air pollutants exceed unhealthy levels. AQI values range from zero to five hundred. Higher values correspond to greater levels of air pollution and increased risk to human health. An AQI value of one hundred is assigned to the concentration of air pollutant equal to its NAAQS. For example, the average eight-hour ozone level considered unhealthy is 0.08 parts per million (ppm). Table 2.3 shows the ozone AQI. Index values are commonly reported during summertime radio and television newscasts to warn people about the dangers of ozone exposure. In State of the Air: 2005 (Spring 2005), the American Lung Association assessed the quality of air in U.S. communities. The organization’s list of the twenty-five metropolitan areas with the worst ozone pollution is shown in Table 2.4. More than ninety-six million people populate these areas. Particulate Matter
Particulate matter (PM) is the general term for the mixture of solid particles and/or liquid droplets found in the air. Primary particles are those emitted directly to the atmosphere—for example, dust, dirt, and soot (black carbon). Secondary particles form in the atmosphere due to complex chemical reactions among gaseous emissions and include sulfates, nitrates, ammoniums, and organic carbon compounds. For example, sulfate particulates can form when sulfur dioxide emissions from industrial facilities and power plants undergo chemical reactions in the atmosphere. The EPA tracks two sizes of particulate matter: PM10 and PM2.5. PM10 are all particles less than or equal to ten Air Quality
23
TABLE 2.4
FIGURE 2.9
The American Lung Association’s list of the 25 metropolitan areas with the worst ozone pollution, 2005 2005 rank* 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 20 22 22 24 25
Other combustion 5%
Metropolitan statistical areas Los Angeles-Long Beach-Riverside, California Bakersfield, California Fresno-Madera, California Visalia-Porterville, California Merced, California Houston-Baytown-Huntsville, Texas Sacramento-Arden-Arcade-Truckee, California-Nevada Dallas-Fort Worth, Texas New York-Newark-Bridgeport, New York-New Jersey-Connecticut-Pennsylvania Philadelphia-Camden-Vineland, Pennsylvania-New Jersey-Delaware-Maryland Washington-Baltimore-Northern Virginia, Washington DC-MarylandVirginia-West Virginia Charlotte-Gastonia-Salisbury, North Carolina-South Carolina Hanford-Corcoran, California Cleveland-Akron-Elyria, Ohio Knoxville-Sevierville-La Follette, Tennessee Modesto, California Pittsburgh-New Castle, Pennsylvania Youngstown-Warren-East Liverpool, Ohio-Pennsylvania Columbus-Marion-Chillicothe, Ohio Detroit-Warren-Flint, Michigan Buffalo-Niagara-Cattaraugus, New York Sheboygan, Wisconsin Chicago-Naperville-Michigan City, Illinois-Indiana-Wisconsin El Centro, California Lancaster, Pennsylvania
*Cities are ranked by using the highest weighted average for any county within that metropolitan area. SOURCE: Adapted from “Table 2b. People at Risk in 25 Most Ozone-Polluted Cities,” in State of the Air 2005, American Lung Association, New York, NY, Spring 2005, http://www.lungusa2.org/embargo/sota05/SOTA05_final.pdf (accessed August 4, 2005)
micrometers in diameter. This is roughly one-seventh the diameter of a human hair and small enough to be breathed into the lungs. PM2.5 are the smallest of these particles (less than or equal to 2.5 micrometers in diameter). PM2.5 is also called fine PM. The particles ranging in size between 2.5 and ten micrometers in diameter are known as coarse PM. Most coarse PM is primary particles, while most fine PM is secondary particles. EMISSIONS AND SOURCES. The EPA tracks trends in direct PM emissions from certain anthropogenic sources, mainly fuel combustion at power plants and in homes and businesses, industrial processes, and transportation exhaust. These are called ‘‘traditionally inventoried sources.’’ As shown in Table 2.2, direct PM10 emissions from these sources declined dramatically between 1970 and 2004.
The EPA believes that the bulk of PM10 in the atmosphere comes from fugitive dust and agricultural and forestry practices that stir up soil. Fugitive dust is dust thrown up into the air when vehicles travel over unpaved roads and during land-disturbing construction activities such as bulldozing. In 2002 these sources were estimated to account for 85% of all PM10 emissions as shown in 24
Emissions of particulate matter smaller than 10 micrometers in diameter, 2002
Air Quality
Traditionally inventoried 10%
Agriculture & forestry 22%
Fugitive dust 63%
SOURCE: Adapted from “Figure 2-43. National Direct PM10 Emissions by Source Category, 2002,” in Air Trends: More Details on Lead, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, December 3, 2003
Figure 2.9. However, these sources are not as great a concern to air quality as the traditionally inventoried sources. This is because soil, dust, and dirt thrown up into the air does not typically travel far from its original location or climb very far into the atmosphere. Direct emissions of PM2.5 also declined between 1990 and 2004. (See Table 2.2.) Most PM2.5 is not comprised of primary particles from direct emissions but of secondary particles that form in the atmosphere. The EPA tracks secondary PM2.5 particle types at monitoring sites around the country. Data collected in 2001 and 2002 indicate that sulfates, ammonium, and carbon are the principal secondary particles found in the eastern part of the nation. These pollutants are largely associated with coal-fired power plants. In western states (particularly California), carbon and nitrates comprise most of the secondary particles. On a national level, secondary PM2.5 concentrations are generally higher in urban areas than in rural areas. AIR QUALITY. When PM hangs in the air, it creates a haze, limiting visibility. PM is one of the major components of smog and can have adverse effects on vegetation and sensitive ecosystems. Long-term exposure to PM can damage painted surfaces, buildings, and monuments.
Figure 2.10 shows the historical trend in PM10 air quality based on data collected by the EPA from 434 The Environment
FIGURE 2.11
FIGURE 2.10
Air quality for particulate matter less than 10 micrometers in diameter, 1988–2003
780 monitoring sites
National Ambient Air Quality Standards 90% of sites have concentrations below this line
40
90% of sites have concentrations below this line
30 Average
20 10
10% of sites have concentrations below this line
0 88 89 90 91 92 93 94 95 96 97 89 99
Concentration, g/m3
Concentration, g/m3
30
434 monitoring sites
60 50
Air quality for particulate matter less than 2.5 micrometers in diameter, 1999–2003
20 National Ambient Air Quality Standards
Average
10
00 01 02 03
1988–2003: 31% decrease 1999–2003: 7% decrease SOURCE: “Figure 12. National PM10 Air Quality,” in The Particle Pollution Report: Understanding Trends Through 2003, U.S. Environmental Protection Agency, Washington, DC, December 2004, http://www.epa.gov/airtrends/pmreport03/pmlooktrends_2405 .pdf#page⫽1 (accessed August 4, 2005)
10% of sites have concentrations below this line
0 99
00
01
02
03
10% decrease
Note: Ammonia is a contributor to PM2.5 formation. However, because of uncertainty in ammonia emission estimates, its trends are not shown here.
monitoring sites. Between 1988 and 2003 PM10 concentrations decreased by 31%. As of April 2005 the EPA reported that dozens of areas around the country were nonattainment for PM10 concentrations. Areas classified ‘‘serious’’ nonattainment were in southern California and parts of Nevada, Arizona, and Washington. In 1999 the EPA began nationwide tracking of PM2.5 air quality concentrations. Between 1999 and 2003 these concentrations decreased by 10% based on data collected from 780 monitoring sites. (See Figure 2.11.) Under the Clean Air Act, states with nonattainment areas must submit to the EPA by 2008 a plan for reducing air pollutant emissions that lead to the formation of PM2.5 particles in the atmosphere. The plan must list the enforceable measures to be taken and provide a schedule to become attainment as quickly as possible. ADVERSE HEALTH EFFECTS. PM can irritate the nostrils, throat, and lungs and aggravate respiratory conditions such as bronchitis and asthma. PM exposure can also endanger the circulatory system and is linked with cardiac arrhythmias (episodes of irregular heartbeats) and heart attacks. PM2.5 particles are the most damaging, because their small size allows them access to deeper regions of the lungs. These small particles (less than or equal to 2.5 micrometers in diameter) have been linked with the most serious health effects in humans. Particulates pose the greatest health risk to those with heart or lung problems, the elderly, and especially children, who are particularly susceptible due to the greater amount of time they spend outside and the fact that their lungs are not fully developed.
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SOURCE: Adapted from “Figure 13. National PM2.5 Air Quality,” in The Particle Pollution Report: Understanding Trends Through 2003, U.S. Environmental Protection Agency, Washington, DC, December 2004, http://www.epa.gov/airtrends/pmreport03/pmlooktrends_2405 .pdf#page⫽1 (accessed August 4, 2005)
Sulfur Dioxide
Sulfur dioxide (SO2) is a gas composed of sulfur and oxygen. The chemical formula SOx is used collectively to describe sulfur oxide, SO2, and other sulfur oxides. EMISSIONS AND SOURCES. One of the primary sources of sulfur dioxide is the combustion of fossil fuels containing sulfur. Coal (particularly high-sulfur coal common to the eastern United States) and oil are the major fuel sources associated with SO2. Power plants have historically been the main source of SO2 emissions. Some industrial processes and metal smelting also cause SO2 to form.
From 1940 to 1970 SO2 emissions increased as a result of the growing use of fossil fuels, especially coal, in industry and power plants. Since 1970 total SO2 emissions have dropped because of greater reliance on cleaner fuels with lower sulfur content and the increased use of pollution control devices, such as scrubbers, to clean emissions. Between 1970 and 2004, SO2 emissions decreased by 51%, according to the EPA. (See Table 2.2.) Fuel combustion in power plants has traditionally produced the majority of sulfur dioxide emissions. In 2003 this source accounted for 68% of SO2 emissions. Air Quality
25
FIGURE 2.12
TABLE 2.5
Sulfur dioxide (SO2) air quality, 1983–2002
Air pollutants, health risks, and contributing sources
[Based on annual arithmetic average] Pollutants Concentration, parts per million
0.04
Ozone* (O3)
244 sites NAAQS*
0.03 90% of sites have concentrations below this line 0.02
10% of sites have concentrations below this line Average
0.01
Particulate matter (PM-10) Carbon monoxide (CO) Sulphur dioxide (SO2) Lead (Pb)
Nitrogen dioxide (NO2)
0.00
Health risks
Contributing sources
Asthma, reduced respiratory function, eye irritation Bronchitis, cancer, lung damage Blood oxygen carrying capacity reduction, cardiovascular and nervous system impairments Respiratory tract impairment, destruction of lung tissue Retardation and brain damage, esp. children
Cars, refineries, dry cleaners Dust, pesticides
Lung damage and respiratory illness
Cars, power plants, wood stoves Power plants, paper mills Cars, nonferrous smelters, battery plants Power plants, cars, trucks
83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 1983–02: 54% decrease 1993–02: 39% decrease *National Ambient Air Quality Standards
“SO2 Air Quality, 1983–2002,” in Latest Findings on National Air Quality: 2002 Status and Trends, U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards, Washington, DC, August 2003 SOURCE:
Fuel combustion at industrial facilities contributed another 14%. All other sources were minor contributors (http://www.epa.gov/airtrends/2005/pdfs/SO2National.pdf ). AIR QUALITY. Trends in air quality concentrations of SO2 are shown in Figure 2.12. The average concentration fell by 54% between 1983 and 2002. As of April 2005 the EPA reported seventeen nonattainment areas around the country for SO2. These included locations in Montana, Utah, New Jersey, West Virginia, Pennsylvania, Kentucky, Ohio, Arizona, and Indiana.
SO2 is a major contributor to acid rain, haze, and particulate matter. Acid rain is of particular concern because acid deposition harms aquatic life by lowering the pH (level of acidity; a lower value indicates more acid) of surface waters, impairs the growth of forests, causes depletion of natural soil nutrients, and corrodes buildings, cars, and monuments. Acid rain is largely associated with the eastern United States because eastern coal tends to be higher in sulfur content than coal mined in the western United States. In 1990 the U.S. Congress established the Acid Rain Program under Title IV of the 1990 Clean Air Act Amendments. The program called for major reductions in SO2 and NOx emissions from certain coal-fired power plants and other combustion units generating electricity around the country. The program set two emissions goals: • Reduce SO2 emissions by approximately half by 2010 compared to the emissions released in 1980 (i.e., from 17.3 million tons per year to 8.95 million tons per 26
Air Quality
*Ozone refers to tropospheric ozone, which is hazardous to human health. SOURCE: Fred Seitz and Christine Plepys, “Table 1. Criteria Air Pollutants, Health Risks, and Sources,” in Monitoring Air Quality in Healthy People 2000, Healthy People 2000 —Statistical Notes, Centers for Disease Control and Prevention, National Center for Health Statistics, Hyattsville, MD, September 1995
year) and maintain a cap of 8.95 million tons per year after 2010 • Achieve a two million ton reduction in NOx emissions compared to the NOx emissions projected for 2000 if the program had not been implemented (i.e., from 8.1 million tons per year to 6.1 million tons per year) The program expects to meets its goals by tightening annual emission limits on thousands of power plants around the country. Inhaling sulfur dioxide in polluted air can impair breathing in those with asthma or even in healthy adults who are active outdoors. As with other air pollutants, children, the elderly, and those with preexisting respiratory and cardiovascular diseases and conditions are most susceptible to adverse effects from breathing this gas. Table 2.5 summarizes the main sources and health risks of all the priority pollutants. ADVERSE HEALTH EFFECTS.
Clean Air Interstate Rule
In March 2005 the EPA issued the Clean Air Interstate Rule (CAIR) to tackle problems in the eastern United States with air pollutants that move across state boundaries. The CAIR puts permanent caps on emissions of NOx and SO2 in twenty-eight eastern states and the District of Columbia. The rule is projected to reduce SO2 emissions by more than 70% and reduce NOx emissions by more than 60% compared to 2003 levels. Control of these pollutants is expected to reduce the formation of fine particulate matter, acid rain, and ground-level ozone across the country. The Environment
The program is to be carried out using the cap-andtrade system. Such a system sets overall caps on emissions but allows companies operating below emission limits to sell ‘‘credits’’ to other companies that are having trouble meeting the limits. The EPA predicts that full implementation of CAIR in 2015 will provide up to $100 billion in annual health benefits and prevent seventeen thousand premature deaths yearly. Improvements are expected in visibility within southeastern national parks, which have been plagued by smog in recent years. Air Toxics Hazardous air pollutants (HAPs), also referred to as air toxics, are pollutants that can cause severe health effects and/or ecosystem damage. Serious health risks linked to HAPs include cancer, immune system disorders, neurological problems, reproductive effects, and birth defects. The Clean Air Act (CAA) lists 188 substances as HAPs and targets them for regulation in section 112 (b) (1). The air toxics program complements the NAAQS program. Examples of HAPs are benzene, dioxins, arsenic, beryllium, mercury, and vinyl chloride.
Major sources of HAP emissions include transportation vehicles, construction equipment, power plants, factories, and refineries. Some air toxics come from common sources. For example, benzene emissions are associated with gasoline. Air toxics are not subject to intensive national monitoring; the EPA and state environmental agencies monitor air toxic levels at approximately three hundred sites nationwide. In 2003 the EPA launched the National Air Toxic Trend Site (NATTS) network. It is designed to follow trends in high-risk air toxics such as benzene, chromium, and formaldehyde. In March 2005 the EPA Office of Inspector General reported on the progress made by the NATTS program (‘‘Progress Made in Monitoring Ambient Air Toxics, but Further Improvements Can Increase Effectiveness,’’ March 2, 2005). The report noted twentythree national sites had been set up to perform NATTS monitoring. The EPA has also awarded grants to state and local environmental agencies to conduct short-term monitoring of air toxics. The report recommended that the EPA focus more attention on locating NATTS monitors in areas of the country where air toxics are estimated to have the highest health risks. In May 2002 the EPA released the latest findings from its National Air Toxic Assessment. The data, which are for 1996, show that approximately 4.6 million tons of air toxics were released into the air, down from a baseline value of six million tons for 1990–93. Air toxics were emitted from many sources, including industrial and mobile (vehicles and nonroad equipment) sources. The known carcinogens posing the greatest risks to human health were benzene NATIONAL AIR TOXIC ASSESSMENT.
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and chromium. The suspected carcinogen showing the greatest risk was formaldehyde. The Toxics Release Inventory (TRI) was established under the Emergency Planning and Community Right-to-Know Act of 1986. The TRI program requires annual reports on the waste management activities and toxic chemical releases of certain industrial facilities using specific toxic chemicals. The TRI list includes more than 650 toxic chemicals. THE
TOXICS
RELEASE
INVENTORY.
In May 2005 the 2003 Toxics Release Inventory (TRI) Public Data Release Report was published. There were nearly 4.44 billion pounds of chemical releases reported by covered facilities during 2003. The vast majority of the releases (88%) were on-site releases to air, land, and water. The remainder were off-site releases (when a facility sends toxic chemicals to another facility where they are then released). On-site air emissions amounted to 1.59 billion pounds and accounted for 40% of the total. CLEAN AIR MERCURY RULE. Mercury is a hazardous air pollutant that can fall out of the atmosphere into water supplies where it is absorbed by fish and shellfish. Consumption of contaminated fish and shellfish is the primary source of mercury exposure to humans.
Figure 2.13 shows the primary sources of mercury emissions to air in the United States for 1990, 1996, and 1999. Emissions from medical waste incinerators and municipal waste combustors declined significantly over this time period. Emissions from miscellaneous sources, such as gold mines and industrial operations, experienced modest decreases. This leaves coal-fired boilers at electric utility plants as the largest single source of mercury emissions. In March 2005 the EPA issued the Clean Air Mercury Rule (CAMR) to limit and reduce mercury emissions from coal-fired power plants. The CAMR program will be based on a cap-and-trade system that will be fully implemented by 2018 and should reduce mercury emissions to fifteen tons per year. According to the EPA, the United States is the only country in the world that regulates mercury emissions from utilities. THE AUTOMOBILE’S CONTRIBUTION TO AIR POLLUTION Highway vehicles are the major source of the air pollutants CO, NOx, and VOCs. According to the Transportation Energy Data Book: Edition 24 (http://cta.ornl. gov/data/tedb24/Edition24_Chapter06.pdf ), the United States leads the world in car ownership. In 2002 there were nearly 850 vehicles per one thousand people in the United States. This rate has more than doubled since 1960, when there were approximately 400 vehicles per one Air Quality
27
FIGURE 2.13
Sources of atmospheric mercury emissions, 1990, 1996, and 1999
Other (Gold mines, institutional boilers, chlorine production, hazardous waste incineration, etc.)
Municipal waste combustors
Medical waste incinerators
Utility coal boilers
250
One of the major failings in reducing auto-induced smog is that efforts have focused on reducing tailpipe emissions instead of eliminating their formation in the first place. Automakers have shown that they can adapt to tighter emission standards by introducing lighter engines, fuel injection, catalytic converters, and other technological improvements. Some experts believe, however, that efforts could be better spent by drastically reducing emissions and promoting alternative energy as well as alternative transportation such as mass transit systems, carpools, and bicycles.
221 tons 196 tons
200 63.56
Tons per year
72.76 150 49.73 112 tons 40.47
100
58.21
56.73 31.78
1.6 4.9
50 51.05
51.25
47.91
1990 emissions
1996 emissions
1999 emissions
0
“Mercury Emissions Have Dropped 45% Since 1990,” in Clean Air Mercury Rule: Charts and Tables, U.S. Environmental Protection Agency, Washington, DC, 2005, http://www.epa.gov/mercuryrule/pdfs/ slide1.pdf (accessed August 4, 2005) SOURCE:
thousand people. With industrialization occurring in many developing countries, an increase in global automobile use and the emissions that accompany them is inevitable. American states that do not meet CAA standards must do something to bring emissions into compliance with national standards. Because of California’s extreme air pollution problems, the Clean Air Act Amendments (CAAA) allowed states to set stricter emission standards than those required by the amendments, which California did. These included strict new laws on automobile pollution. The remaining forty-nine states were given the option of choosing either the standards of California or the federal CAAA. States have the freedom to cut their emissions in whatever manner they choose. Some states have tougher tests for auto emissions than others. In some major metropolitan areas, particularly in the Northeast, owners of cars and light trucks are required to pay for exhaust emission tests. For those that do not pass, repairs must be made to bring them into compliance. 28
Air Quality
Reformulated Gasoline Reformulated gasoline (RFG) is gasoline that contains added oxygen. This process produces a loweroctane fuel and usually an increase in price. Oxygenation of fuel makes combustion more complete. Incomplete fuel combustion is a major cause of carbon monoxide (CO) emissions. RFG is specially blended to have lower concentrations of certain volatile organic compounds (VOCs) in order to reduce ozone formation and emissions of air toxins. Although RFG combustion results in lower CO emissions, higher carbon dioxide (CO2) emissions result due to the presence of additional oxygen.
The most frequently used oxygenates in RFG are ethanol and methyl tertiary-butyl ether (MTBE). Fuel ethanol is derived from fermented agricultural products such as corn. More than 99% of fuel ethanol is produced in the United States, primarily in the corn-growing regions of the Midwest. MTBE is a chemical compound made from methanol and isobutylene. The CAA standards that went into effect in 1995 required those areas with the worst polluted air to sell RFG. Denver, Colorado, known for its ‘‘brown cloud’’ of pollution, enacted the nation’s first oxygenated fuels program—an entire winter period during which all fuels sold at gas stations were required to have a 3% oxygen content. Other areas voluntarily chose to participate in RFG programs. By the early 2000s RFG accounted for more than one-third of all gasoline sold. MTBE was historically dominated as the RFG oxygenator of choice. MTBE demand has fallen, primarily due to environmental concerns. It is very soluble in water and therefore tends to migrate to water supplies. As of August 2003 the U.S. Geological Survey reported that MTBE was found in source water four to five times more often in RFG areas than in non-RFG areas. As of June 2005 MTBE use is banned or severely limited in approximately half the states, including New York and California. MTBE bans are expected to greatly increase use of fuel ethanol in RFG. Beginning in the late 1990s, customer complaints about gasoline prices caused many areas that had voluntarily opted to sell RFG to back out. Even before these The Environment
price spikes occurred, many states were concerned about the effects of RFG requirements on gasoline prices. In 1999 California asked the federal government for a waiver from the oxygenate requirement. Such a waiver would allow the state to temporarily use non-RFG in case of RFG supply and distribution problems. In 2001 the waiver was denied. Over the next several years waivers were requested by several other states and again by California. In 2005 the EPA denied waiver requests from California, Connecticut, and New York.
FIGURE 2.14
Vehicle fuel economy by model, 1975–2004
Cars
Both
Trucks
30
CAFE standards required each domestic automaker to increase the average mileage of the new cars sold to 27.5 miles per gallon (mpg) by 1985. Under CAFE rules automakers could still sell the big, less efficient cars with powerful eight-cylinder engines, but to meet average fuel efficiency rates they also had to sell smaller, more efficient cars. Automakers that failed to meet each year’s CAFE standards were required to pay fines. Those who managed to surpass the rates earned credits that they could use in years when they fell below CAFE requirements. The CAFE standard was lowered during the mid- to late 1980s and then raised back to 27.5 mpg for 1990 model automobiles. In 1996 a standard of 20.7 mpg was established for light trucks. This category includes pickup trucks, minivans, and SUVs. According to the U.S. Department of Transportation (DOT), automobile manufacturers achieved an average 29.5 mpg fuel economy for model year 2003 cars, thus meeting the standard. Likewise, the average light truck fuel economy was 21.7 mpg, also above the standard. In 2003 the National Highway Traffic Safety Administration issued a rule setting new CAFE standards for light trucks produced in model years 2005–07. The standard increased to 21.0 mpg for 2005, to 21.7 mpg for 2006, and to 22.2 mpg for 2007.
Miles per gallon
25
Government Regulation—Corporate Average Fuel Economy Standards In 1973 the Organization of Petroleum Exporting Countries (OPEC) imposed an oil embargo that provided a painful reminder to Americans of how dependent the country had become on foreign sources of fuel. Congress passed the 1975 Automobile Fuel Efficiency Act (PL 96–426), which set the initial Corporate Average Fuel Economy (CAFE) standards.
20
15
10 1975
1980
1985
1990
1995
2000
2005
Model year SOURCE: “Karl H. Hellman and Robert M. Heavenrich, “Adjusted Fuel Economy by Model Year (Three-Year Moving Average),” in Light-Duty Automotive Technology and Fuel Economy Trends: 1975 Through 2004, U.S. Environmental Protection Agency, Office of Transportation and Air Quality, Washington, DC, April 2004,http:// www.epa.gov/otaq/cert/mpg/fetrends/420r04001.pdf (accessed August 4, 2005)
issued to manufacturers for alternative fuel capabilities and other factors. Rates published by the EPA and DOE are approximately 15% lower, as they reflect only actual ‘‘real world’’ experience. According to the 2004 EPA report Light-Duty Automotive Technology and Fuel Economy Trends: 1975 through 2004, ‘‘real world’’ average estimates of fuel economy for model year 2004 cars and light trucks were 24.6 mpg and 17.9 mpg, respectively. Figure 2.14 shows average ‘‘real world’’ fuel economy rates for model years 1975 through 2004. The combined rate for both cars and trucks decreased during the 1990s because of increased demand for light trucks, particularly SUVs. Market Factors
‘‘Real World’’ Estimates of Fuel Economy Fuel economy rates calculated by DOT for comparison to CAFE standards are not the same as rates reported to consumers on new vehicle labels or commonly published by the EPA or U.S. Department of Energy (DOE) in fuel economy guides. DOT CAFE rates are calculated based on laboratory data and take into account credits The Environment
In 1985 cars accounted for nearly 80% of new sales. By 2004 their market share had fallen to around 50%. Sales of SUVs and minivans increased dramatically over the same time period. These light trucks have lower fuel economy rates than cars. Also, many states have increased interstate speed limits since the 1980s. This has also lowered overall fuel efficiency. Air Quality
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SUVs and minivans fall under less stringent emissions standards than automobiles because they originated as modifications of light-truck bodies and are classified as trucks. Automakers and buyers of trucks and SUVs oppose tightening restrictions on emissions of these vehicles, although critics contend that new SUVs are more like cars than trucks in design.
supplying alternative fuels will be developed simultaneously with the vehicles. As of June 2005 there were just over five thousand of these stations around the country. Most of them (62%) provide liquefied petroleum gas, followed by compressed natural gas (16%), electricity (11%), and Ethanol85 (6%). California and Texas together account for slightly more than one-third of all the stations.
U.S. industry officials claim that increasing fuel efficiency is not cost effective. With each mile added in efficiency, the costs to obtain that improvement increase to the point that it is no longer cost effective. This is the same objection that is made, in general, about cleaning up many environmental hazards—that the first and most drastic improvements are the least expensive and thereafter cleanup becomes more costly.
Market success of alternative fuels and AFVs depends on public acceptance. People are accustomed to using gasoline as their main transportation fuel, and it is readily available. As federal and state requirements for alternative fuels increase, so should the availability of such fuels as well as their acceptance by the general public. In the long run, electricity and hydrogen seem the most promising of the alternative fuels for vehicles.
Alternative Fuels The DOE defines alternative fuels as those that are ‘‘substantially non-petroleum and yield energy security and environmental benefits.’’ The DOE recognizes all of the following as alternative fuels:
• Compressed or liquefied natural gas • Coal-derived liquid fuels • Liquefied petroleum gas • Alcohol fuels (mixtures that contain at least 70% alcohol) • Bio fuels (fuels derived from biological materials) • Electricity • Solar energy • Hydrogen Table 2.6 summarizes information for the major alternative fuels related to their physical state, sources, environmental impacts, and availability. Although these fuels offer advantages, their use may substitute one problem for another. For example, the alcohol fuel methanol reduces ozone formation but increases formaldehyde, a human carcinogen, and is twice as toxic as gasoline if it comes in contact with the skin. Engines require twice as much methanol as gasoline to travel a similar distance. Natural gas reduces hydrocarbons and CO but increases NOx. The DOE reports that more than half a million alternative fuel vehicles (AFVs) were in use in the United States in 2004. (See Table 2.7.) Most relied on liquefied petroleum gas (35%), followed by alcohol fuel containing at least 85% ethanol (27%), compressed natural gas (26%), and electricity (10%). ALTERNATIVE FUELS AND THE MARKETPLACE. AFVs cannot become a viable transportation option unless a fuel supply is readily available. Ideally, the infrastructure for
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Air Quality
ELECTRIC VEHICLES—PROMISE AND REALITY. The electric vehicle (EV) is not a new invention. Popular during the 1890s, the quiet, clean, and simple vehicle was expected to dominate the automotive market of the twentieth century. Instead, it quietly disappeared as automakers chose to invest billions of dollars in the internal combustion engine. It has taken a century, but the EV has returned.
The primary difficulty with EVs lies in inadequate battery power. The cars have a range of seventy to one hundred miles on a single charge and must be recharged often. In addition, EVs are expensive. Despite their high price, EVs have many advantages, including low noise, simple design and operation, and low service and maintenance costs. Over time the cost gap between cars that pollute and EVs that do not will narrow. With advances in battery development, the gap could close entirely. HYDROGEN-FUELED VEHICLES ON THE HORIZON.
Hydrogen is the simplest naturally occurring element and can be found in materials such as water, natural gas, and coal. For decades advocates of hydrogen have promoted it as the fuel of the future—abundant, clean, and cheap. Hydrogen researchers from universities, laboratories, and private companies claim that their industry has already produced vehicles that could be ready for consumers if problems of fuel supply and distribution could be solved. Other experts contend that economics and safety concerns will limit hydrogen’s wider use for decades. In 2002 the DOE formed a government-industry partnership called Freedom Cooperative Automotive Research (FreedomCAR). The goal of FreedomCAR is to develop highly fuel-efficient vehicles that operate using hydrogen produced from renewable energy sources. Industrial partners in the venture include Ford, General Motors, and Daimler-Chrysler. FreedomCAR research takes place at facilities operated by the DOE’s National Renewable Energy Laboratory in Golden, Colorado. The Environment
The Environment
Air Quality
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Liquid
All types of vehicle classes
Produces harmful emissions; however, gasoline and gasoline vehicles are rapidly improving and emissions are being reduced Available at all fueling stations
Physical state
Types of vehicles available today
Environmental impacts of burning the fuel
Produces harmful emissions; however, diesel and diesel vehicles are rapidly improving and emissions are being reduced especially with after-treatment devices Available at select fueling stations
Many types of vehicles classes
Liquid
Crude oil
No. 2 diesel
Available in bulk from an increasing number of suppliers. There are 22 states that have some biodiesel stations available to the public
Reduces particulate matter and global warming gas emissions compared to conventional diesel; however, NOx emissions may be increased
Any vehicle that runs on diesel today—no modifications are needed for up to 5% blends. Many engines also compatible with up to 20% blends
Liquid
Soy bean oil, waste cooking oil, animal fats, and rapeseed oil
Biodiesel
More than 1,100 CNG stations can be found across the country. California has the highest concentration of CNG stations. Home fueling will be available in the fall of 2005.
CNG vehicles can demonstrate a reduction in ozone forming emissions compared to some conventional fuels, however, HC emissions may be increased
Many types of vehicle classes
Compressed gas
Underground reserves
Compressed natural gas (CNG)
Most homes, government facilities, fleet garages, and businesses have adequate electrical capacity for charging, but, special hookup or upgrades may be required. More than 600 electric charging stations are available in California and Arizona.
EVs have zero tailpipe emissions; however, some amount of emissions can be contributed to power generation
Neighborhood electric vehicles, bicycles, lightduty vehicles, medium and heavy duty trucks and buses
Coal; however, nuclear, natural gas, hydroelectric, and renewable resources can also be used N/A
Electricity
Most of the E-85 fueling stations are located in the Midwest, but in all, approximately 150 stations are available in 23 states
Light-duty vehicles, medium and heavy-duty trucks and buses— these vehicles are flexible fuel vehicles that can be fueled with E85 (ethanol), gasoline, or any combination of the two fuels E-85 vehicles can demonstrate a 25% reduction in ozone-forming emissions compared to reformulated gasoline
Liquid
Corn, grains, or agricultural waste
Ethanol (E85)
LNG vehicles can demonstrate a reduction in ozone forming emissions compared to some conventional fuels, however, HC emissions may be increased
Medium and heavy-duty trucks and buses
Liquid
Underground reserves
Liquified natural gas (LNG)
There are only a Public LNG small number of stations are hydrogen stations limited (only 35 across the country. nationally), LNG Most are available is available for private use through several only. suppliers of cryogenic liquids
Zero regulated emissions for fuel cell-powered vehicles, and only NOx emissions possible for internal combustion engines operating on hydrogen
Compressed gas or liquid No vehicles are available for commercial sale yet, but some vehicles are being leased for demonstration purposes
Natural gas, methanol, and other energy sources
Hydrogen
LPG is the most accessible alternative fuel in the U.S. There are more than 3,300 stations nation wide.
LPG vehicles can demonstrate a 60% reduction in ozone-forming emissions compared to reformulated gasoline
Light-duty vehicles, which can be fueled with propane or gasoline, medium and heavy-duty trucks and buses that run on propane
Liquid
A by-product of petroleum refining or natural gas processing
Liquefied petroleum gas (LPG)
Methanol remains a qualified alternative fuel as defined by EPAct, but it is not commonly used
M-85 vehicles can demonstrate a 40% reduction in ozone-forming emissions compared to reformulated gasoline
Mostly heavy-duty buses are available
Liquid
Natural gas, coal, or, woody biomass
Methanol (M85)
Adapted from Alternative Fuels Comparison Chart, U.S. Department of Energy, National Renewable Energy Laboratory, Alternative Fuels Data Center, Golden, CO, 2005, http://www.eere.energy.gov/afdc/ pdfs/afv_info.pdf (accessed August 4, 2005)
SOURCE:
Fuel availability
Crude oil
Main fuel source
Gasoline
Characteristics of major alternative fuels
TABLE 2.6
TABLE 2.7
Number of alternative fuel vehicles in use, 1995–2004
Fuel type
1995
1998
2000
2001
2002
2003
2004a
Average annual percentage change 1995–2004
LPG CNG LNG M85 M100 E85b E95 Electricity
172,806 50,218 603 18,319 386 1,527 136 2,860
177,183 78,782 1,172 19,648 200 12,788 14 5,243
181,994 100,750 2,090 10,426 0 87,570 4 11,830
185,053 111,851 2,576 7,827 0 100,303 0 17,847
187,680 120,839 2,708 5,873 0 120,951 0 33,047
190,438 132,988 3,030 4,917 0 133,776 0 45,656
194,389 143,742 3,134 4,592 0 146,195 0 55,852
1.3% 12.4% 20.1% ⫺14.3% ⫺100.0% 66.0% ⫺100.0% 13.0%
Total
246,855
295,030
394,664
425,457
471,098
510,805
547,904
9.3%
a
2004 data are based on plans or projections. Does not include flex-fuel vehicles.
b
Stacy C. Davis and Susan W. Diegel, “Table 6.1. Estimates of Alternative Fuel Vehicles in Use, 1995–2004,” in Transportation Energy Data Book: Edition 24, U.S. Department of Energy, Office of Planning, Budget Formulation and Analysis, Energy Efficiency and Renewable Energy, Washington, DC, December 2004, http://cta.ornl.gov/data/tedb24/Edition24_Chapter06.pdf (accessed August 4, 2005) SOURCE:
In his 2003 State of the Union Address, President George W. Bush announced the creation of the Hydrogen Fuel Initiative (HFI). This $1.2 billion program is designed to develop the technology needed for commercially viable hydrogen-powered fuel cells by the year 2020. Fuel cells designed for transportation vehicles and home/business use are to be developed. The HFI has three primary missions as part of its goals:
FIGURE 2.15
Diagram of a hybrid-electric vehicle
1 – Engine
3 – Electric motor
5 – Fuel tank
2 – Transmission
4 – Power electronics
6 – Battery pack
• Lower the cost of hydrogen production to make it cost effective with gasoline production by the year 2010 • Develop hydrogen fuel cells that provide the same vehicle range (at least three hundred miles of travel) as conventional gasoline fuel tanks • Lower the cost of hydrogen fuel cells to be comparable in cost with internal combustion engines
6 5 4 3 1 2
The U.S. Department of Energy predicts that hydrogen fuel cell vehicles will reach the mass consumer market in 2020. Many experts believe that the most feasible solution in the near future is to produce vehicles that use a combination of gasoline and one of the alternative fuel sources. These are called advanced technology vehicles or hybrid vehicles. Figure 2.15 depicts a hybrid automobile that relies on a small internal combustion engine and electricity (from batteries). ADVANCED TECHNOLOGY VEHICLES (HYBRIDS).
Table 2.8 provides information about the various hybrid vehicles for sale in the United States as of December 2004. Manufacturers continue research on hybrid cars, which they hope will eventually satisfy American tastes and pocketbooks and provide even greater fuel efficiency. 32
Air Quality
SOURCE: Model Year 2002 Fuel Economy Guide, U.S. Department of Energy and U.S. Environmental Protection Agency, Washington, DC, October 2001
THE COST OF AIR POLLUTION AND POLLUTION CONTROL
Air quality plays a major and complex role in public health. Among the factors that must be considered are the levels of pollutants in the air, the levels of individual exposure to these pollutants, individual susceptibility to toxic substances, and exposure time related to ill effects from certain substances. Blaming health effects on specific pollutants is also complicated by the health impact of nonenvironmental causes (such as heredity or poor diet). The Environment
TABLE 2.8
Sales and specifications of available advanced technology vehicles as of 2004 Fuel economy (city/hwy)
Emissions rating
Passenger capacity
Cargo capacity
Price
57/56 60/51 48/47
SULEV-2 AT-PZEV ULEV
2 5 5
16.3 ft3 16.1 ft3 10.1 ft3
$21,380 $20,875 $19,800
36/31 33/29
AT-PZEV
5
27.6 ft3
$26,380 $28,005
18/21 17/19
ULEV
5
56.9 ft3
$30,345 $31,835
18/21 17/19
ULEV
5
43.5 ft3
$28,132
2005 Honda Insight CVTa 2005 Toyota Prius CVTa 2005 Honda Civic Hybrid CVT SULEVa 2005 Ford Escape Hybrid 2WD 4WD 2005 Chevrolet Silverado Hybrid 2WD 4WD 2005 GMC Sierra Hybrid 2WD 4WD
Calendar year sales in the U.S. 2005 Honda Insight CVT 2005 Toyota Prius CVTa
a
1999
2000
2001
2002
2003
2004b
17 0
3,788 5,562
4,726 15,556
2,216 20,119
1,168 24,627
570 41,838
Note: SULEV⫽Super ultra low emission vehicle. AT-PZEV⫽Advanced technology partial zero emission vehicle. a Specifications are for the model containing a continuously variable transmission (CVT). b Sales through October 2004.
Stacy C. Davis and Susan W. Diegel, “Table 6.5. Sales and Specifications of Available Advanced Technology Vehicles,” in Transportation Energy Data Book: Edition 24, U.S. Department of Energy, Office of Planning, Budget Formulation and Analysis, Energy Efficiency and Renewable Energy, Washington, DC, December 2004, http://cta.ornl.gov/data/tedb24/Edition24_Chapter06.pdf (accessed August 4, 2005) SOURCE:
Scientists do know that air pollution is related to a number of respiratory diseases, including bronchitis, pulmonary emphysema, lung cancer, bronchial asthma, eye irritation, weakened immune system, and premature lung tissue aging. In addition, lead contamination causes neurological and kidney disease and can be responsible for impaired fetal and mental development. The American Lung Association estimates the annual health costs of exposure to the most serious air pollutants at $40 to $50 billion. Like most environmental issues, pollution involves limits. There is only so much air to receive automobile emissions and so much land on which freeways can be built. Many transportation analysts think that interest in public transportation is long overdue. Several major cities, including San Francisco, Chicago, and New York, have had positive environmental results with mass transit systems. A major problem with the effort to reduce air pollution further—as well as some other types of pollution—is that most of the relatively cheap fixes have already been made, and many economists argue that the expensive ones may not be worth the price. The very premise of cleanup—that air pollution can be reduced to levels where it no longer poses any health risk at all—is questioned not just by industry but by observers as well. Virtually all gains in the war on ozone have been achieved by reducing auto emissions. The costs for future air quality improvements, from some points of view, may exceed the value of any improvement, and the disparity The Environment
may only get worse over time. However, some sources believe that there are other technologically easy—if politically unpopular—steps that could be taken to improve air quality. Such steps would include forcing light trucks, minivans, and SUVs to meet the same smog standards as standard passenger cars. Other possible improvements could come from changes in ‘‘grandfather’’ clauses—that is, loopholes that exempt companies from compliance with laws because the companies existed prior to the law. Power plants rank first in grandfathered emissions. Other top industries affected by grandfather clauses include aluminum smelters, oil refineries, and carbon-black plants. THE CLEAN AIR ACT—A HUGE SUCCESS In 1970 the U.S. Congress passed the landmark CAA, proclaiming that it would restore urban air quality. It was no coincidence that the law was passed during a fourteen-day Washington, D.C., smog alert. The act was amended several times over the following decades, including a massive overhaul in 1990 resulting in the CAAA. Although the act has had mixed results, and many goals remain to be met, most experts credit it with making great strides toward cleaning up the air.
The CAAA encouraged states to pursue marketbased approaches to improve air quality. One such program, the Accelerated Vehicle Retirement program, commonly known as Cash for Clunkers, provides economic incentives for the owners of highly polluting vehicles to retire their automobiles from use or repair Air Quality
33
them. The program gives pollution credits to private corporations for contributing funding to car dealers to entice car owners to trade in their old vehicles. Resistance to CAAA Gets Federal Concessions During the mid- to late 1990s, a number of states began balking at the strict auto emissions testing that seemed necessary to comply with the CAAA. Under the law, if a reduction does not come from auto emissions, it would have to be made up by other sources—for example, smokestack industries. The states are free to implement whatever methods they choose to cut pollution, but most states with serious air quality problems had previously chosen, with EPA encouragement, the stricter car inspection programs. This meant that many states were faced with testing that a great number of consumers considered overly restrictive and expensive.
The EPA had counted on enforcing the program through sanctions specified by the CAAA, which included cutting off highway money and other federal aid to the states. Some state legislatures, however, seemed willing to forego this aid in what some considered an act of civil disobedience. Rather than provoking a confrontation with the states, the EPA chose to allow greater flexibility in auto emissions testing. In The Benefits and Costs of the Clean Air Act, 1970 to 1990 (1997), the first report mandated by the CAA on the monetary costs and benefits of controlling pollution, the EPA concluded that the economic value of clean air programs was forty-two times greater than the total costs of air pollution control during the twenty-year period. The study found that numerous positive consequences occurred in the U.S. economy because of CAA programs and regulations. The CAA affected industrial production, investment, productivity, consumption, employment, and economic growth. In fact, the study estimated that total agricultural benefits from the CAA were almost $10 billion. The EPA compared benefits to direct costs or expenditures. The total costs of the CAA were $523 billion for the twenty-year period; total benefits equaled $22.2 trillion—a net benefit of approximately $21.7 trillion. In Two Decades of Clean Air: EPA Assesses Costs and Benefits (1998), the National Conference of State Legislatures used data from the EPA analysis and found that the act produced major reductions in pollution that causes illness and disease, smog, acid rain, haze, and damage to the environment. The Benefits and Costs of the Clean Air Act Amendments of 1990 (2000), the second mandated review of the CAA and the most comprehensive and thorough review ever conducted, showed similar results. Using a sophisticated array of computer models and the latest cost data, the EPA found that, by 2010, the act will have prevented 34
Air Quality
twenty-three thousand Americans from dying prematurely and averted more than 1.7 million asthma attacks. The CAA will prevent sixty-seven thousand episodes of acute bronchitis, ninety-one thousand occurrences of shortness of breath, 4.1 million lost work days, and thirty-one million days in which Americans would have had to restrict activity because of illness. Another twentytwo thousand respiratory-related hospital admissions will be averted, as well as forty-two thousand admissions for heart disease and forty-eight hundred emergency room visits. The EPA estimated that the benefits of CAA programs in reduction of illness and premature death alone will total about $110 billion. By contrast, the study found that the cost of achieving these benefits was only about $27 billion, a fraction of the value of the benefits. In addition, the study reported that there were other benefits that scientists and economists cannot quantify and express in monetary terms, such as controlling cancercausing air toxins and bringing benefits to crops and ecosystems by reducing pollutants. At the same time, many cities are still not in compliance with the law. One reason efforts to clean the air have been only partly successful is that they have focused on specific measures to combat individual pollutants rather than addressing the underlying social and economic structures that create the problem—for example, the distance between many Americans’ residences and their places of work. Trading Pollution Credits In another federal concession, the CAAA created pollution ‘‘credits,’’ a free-market innovation that allowed companies that keep their emissions below standards to sell or trade their credits on the open market to other companies that do not keep their emissions below standards. This is often viewed essentially as permission to pollute. Companies can also choose to retire their credits permanently and thus reduce the potential of further pollution. THE ANTIREGULATORY REBELLION The dissatisfaction with government regulation that developed in the 1980s grew even stronger in the 1990s. The Republican-led Congress took steps to put the brakes on what it considered growing environmental regulation. As a result, the funding was cut for environmental protection—including the CAA, the CAAA, the Clean Water Act (PL 92–500), the Safe Drinking Water Act (PL 93– 523), and other environmental statutes. Subsequent fiscal budgets continued those cuts by many millions of dollars.
The CAA requires the EPA to review public health standards at least every five years to ensure they reflect the best current science. In 1997—in response The Environment
to what many consider compelling scientific evidence of the harm caused to human health by ozone and fine particles—the EPA issued new, stricter air quality standards for ozone and PM. This was the first revision in ozone standards in twenty years and the first-ever standard for fine particulates. The provisions tightened the standard for groundlevel ozone from the level of 0.12 parts per million (ppm) at the highest daily measurement to 0.08 ppm average over an eight-hour period. The new PM standard included particles larger than 2.5 microns in diameter instead of the original standard of those larger than ten microns. However, in May 1999 a three-judge federal appeals panel overturned the new standards. The EPA appealed, but in October 1999 the full U.S. Court of Appeals for the District of Columbia refused to overturn the decision. In January 2000 the American Lung Association petitioned the U.S. Supreme Court to review the decision. The Supreme Court ruled in February 2001 that the EPA had the authority under the CAA to set the new standards. Claims that the EPA’s decision was arbitrary and capricious and not supported by evidence were struck down by the D.C. Circuit Court in late May 2002. PUBLIC OPINION ABOUT AIR POLLUTION Every year the Gallup Organization conducts a poll on the environment around the time of the nation’s celebration of Earth Day. In the March 2004 poll participants were asked about their level of concern related to particular environmental problems. (See Table 2.9). The results showed that 39% of those asked expressed a great deal of concern about air pollution, compared with 30% who expressed a fair amount of
The Environment
TABLE 2.9
Public concern about air pollution, 1989–2004 “PLEASE TELL ME IF YOU PERSONALLY WORRY ABOUT THIS PROBLEM A GREAT DEAL, A FAIR AMOUNT, ONLY A LITTLE, OR NOT AT ALL. AIR POLLUTION?”
2004 Mar 8–11 2003 Mar 3–5 2002 Mar 4–7 2001 Mar 5–7 2000 Apr 3–9 1999 Apr 13–14 1999 Mar 12–14 1997 0ct 27–28 1991 Apr 11–14 1990 Apr 5–8 1989 May 4–7
Great deal %
Fair amount %
Only a little %
Not at all %
No opinion %
39 42 45 48 59 52 47 42 59 58 63
30 32 33 34 29 35 33 34 28 29 24
23 20 18 14 9 10 16 18 10 9 8
8 6 4 4 3 3 4 5 4 4 4
* * * * * * * 1 * * *
SOURCE: “Please tell me if you personally worry about this problem a great deal, a fair amount, only a little, or not at all. Air pollution?” in Poll Topics and Trends: Environment, The Gallup Organization, Princeton, NJ, March 17, 2004, www.gallup.com (accessed August 4, 2005). Copyright © 2004 by The Gallup Organzation. Reproduced by permission of The Gallup Organization.
concern. Another 23% indicated a little concern, and 8% expressed no concern. The percentage of poll respondents indicating a great deal of concern about air pollution has dropped dramatically in recent years from a high of 63% in 1989. In a poll conducted in 2003 Gallup asked people their opinion about some specific environmental proposals to help the nation’s energy situation. The results indicated that people strongly favor tougher enforcement of environmental regulations and higher emissions standards for automobiles and business and industry sources.
Air Quality
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CHAPTER 3
THE ENHANCED GREENHOUSE EFFECT AND CLIMATE CHANGE
WHAT IS CLIMATE? Climate and weather are not the same thing. Both describe conditions in the lower atmosphere—for example, wet or dry, cold or warm, stormy or fair, and cloudy or clear. Weather is the short-term local state of the atmosphere. Weather conditions can change from moment to moment and can differ in two places that are relatively close together. Climate describes the average pattern of weather conditions experienced by a region over a long period of time. For example, Florida has a warm climate but can experience days and even weeks of cold weather.
Earth’s climate as a whole has not changed much for a few thousand years. In general, most of the planet has been warm enough for humans, animals, and plants to thrive. This was not so in the distant past when the climate fluctuated between long periods of cold and warmth, each lasting for many thousands of years. Scientists are not sure what triggered these major climate changes. A variety of factors are believed to be involved, including movement of the tectonic plates, changes in Earth’s orbit around the Sun, and variations in atmospheric gases. Scientists believe that the last ice age occurred about eighteen thousand years ago. During this period ice sheets and glaciers spread to cover vast regions of the Earth, including most of North America and Europe. According to the Environmental Protection Agency (EPA), the average temperature of the Earth during the last ice age was only 7 degrees Fahrenheit colder than it is today. This shows the enormous effects that minor changes in global temperature can cause. Earth’s temperature depends on a delicate balance of energy inputs and outputs, chemical processes, and physical phenomena. As shown in Figure 3.1 solar radiation passes through Earth’s atmosphere and warms the Earth. The Earth emits infrared radiation. Some outgoing infraThe Environment
red radiation is not allowed to escape into outer space but is trapped beneath the atmosphere. The amount of energy that is trapped depends on many variables. One major factor is atmospheric composition. Some gases, such as water vapor, carbon dioxide (CO2), and methane (CH4), act to trap heat beneath the atmosphere in the same way that glass panels trap heat in a greenhouse. The panels allow sunlight into the greenhouse, but prevent heat from escaping. Earth’s surface temperature is about 60 degrees Fahrenheit warmer than it would be if natural greenhouse gases were not present. Without this natural warming process, Earth would be much colder and could not sustain life as it now exists. It is necessary, however, to distinguish between the ‘‘natural’’ and a possible ‘‘enhanced’’ greenhouse effect. The natural greenhouse effect provides a warm atmosphere for Earth that is necessary for life. The theory behind the enhanced greenhouse effect is that human activities can load the atmosphere with too much carbon dioxide and other heat-trapping gases. This could increase Earth’s temperature above that expected from the natural greenhouse effect, an effect known as global warming. Such a temperature increase would be accompanied by major climatic changes. The primary human activities linked to the enhanced greenhouse effect are the burning of fossil fuels (mainly coal and oil) and their derivatives (such as gasoline), and destruction of large amounts of vegetation that normally absorb carbon dioxide. (See Figure 3.2.) GREENHOUSE GASES Greenhouse gases are gases in the atmosphere that allow shortwave radiation (sunlight) from the Sun to pass through to Earth but absorb and reradiate longwave infrared radiation (heat) coming from the Earth’s surface. This process serves to 37
FIGURE 3.1
Role of radiation in greenhouse effect
Some solar radiation is reflected by the earth and the atmosphere Solar radiation passes through the clear atmosphere
Some of the infrared radiation passes through the atmosphere, and some is absorbed and re-emitted in all directions by greenhouse gas molecules. The effect of this is to warm the earth’s surface and the lower atmosphere.
Infrared radiation is emitted from the earth’s surface
Most radiation is absorbed by the earth’s surface and warms it
Environmental Health Center of the National Safety Council, water vapor comprises as much as 2% of the atmosphere and is responsible for approximately twothirds of the natural greenhouse effect. Scientists believe, however, that humans have little to no influence on the amount of water vapor in the atmosphere. Water vapor is part of the natural water cycle that takes place on and around the Earth. Water evaporates from the surface, condenses into clouds, and then returns to the surface as precipitation. The water cycle is also a heat cycle, transferring heat around the Earth and back and forth between the surface and the atmosphere. Water vapor cycles quickly through the atmosphere, lingering for a few days at most. Carbon Dioxide
“The Greenhouse Effect,” in Global Warming Kid’s Site: Greenhouse Effect, U.S. Environmental Protection Agency, Washington, DC, July 12, 2004, http://www.epa.gov/globalwarming/ kids/greenhouse.html (accessed August 4, 2005)
SOURCE:
warm the lower atmosphere (the troposphere). The troposphere extends from the Earth’s surface to approximately five to eight miles above the surface, as shown in Figure 3.3. Water Vapor
Scientists know that water vapor is the most prevalent greenhouse gas in the atmosphere. According to the
Carbon dioxide (CO2) is a heavy colorless gas that comprises approximately 0.035% of the atmosphere. Carbon dioxide is a respiration product from all living things (plants, animals, and humans). It is also released during the decay or combustion of organic materials. Huge amounts of carbon dioxide are cycled back and forth between the oceans and the atmosphere. Likewise, vegetation absorbs carbon dioxide from the air. The result of all these processes is a global carbon cycle that maintains carbon dioxide at suitable levels in the atmosphere to sustain a natural greenhouse effect. Prior to the 1800s humans had little impact on atmospheric carbon dioxide levels. The Industrial Revolution ushered in widespread use of fossil fuels, primarily coal, oil, and natural gas. Combustion of
FIGURE 3.2
Greenhouse effect Ozone layer shields the Earth from the sun’s harmful ultraviolet radiation.
Space
Reflected energy
Outgoing energy (infrared heat)
Incoming energy (ultraviolet light)
phere
Atmos
Trapped IR radiation SOURCE: Looking
38
at the Earth from Space, National Aeronautics and Space Administration, Washington, DC, 1994
The Enhanced Greenhouse Effect and Climate Change
The Environment
FIGURE 3.3
Layers of the atmosphere UV/visible sunlight
Mesosphere Infrared radiation Stratosphere 0˚F ~50 km (30 miles)
Ozone layer
Troposphere Mt Everest ~9 km (5.5 miles)
80˚F ~8 km (5 miles) Infrared radiation ~9–12 km (5.5–7.5 miles) 60˚F
“Regions of the Atmosphere,” in Stratospheric Ozone: Monitoring and Research in NOAA, U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Washington, DC, April 24, 2001, http://www.ozonelayer.noaa.gov/science/regions.jpeg (accessed August 4, 2005) SOURCE:
these carbon-loaded fuels releases large amounts of carbon dioxide. The burning of fossil fuels by industry and motor vehicles is, by far, the leading source of CO2 emissions in the United States, accounting for 95% of the nation’s emission of greenhouse gases in 2003. (See Table 3.1.) Other anthropogenic (humancaused) sources include deforestation, burning of biomass (combustible organic materials, such as wood scraps and crop residues), and certain industrial processes. The atmospheric lifetime of carbon dioxide is estimated to be fifty to two hundred years. THE ROLE OF THE FORESTS AS CARBON SINKS. Forests act as sinks, or repositories, absorbing and storing carbon. Trees naturally absorb and neutralize CO2, although scientists do not agree on the extent to which forests can soak up excess amounts. The increasing levels of CO2 in the atmosphere might conceivably be tolerated in Earth’s normal CO2 cycle if not for the additional complicating factor of deforestation. The burning of the Amazon rain forests and other forests has had a twofold effect: the immediate release of large amounts of CO2 into the atmosphere from the fires, and the loss of trees to neutralize the CO2 in the atmosphere. (See Figure 3.4.) THE ROLE OF THE OCEANS AS CARBON SINKS. The oceans are, by far, the largest reservoir of carbon in the carbon cycle. Oceanographers and ecologists disagree over the carbon cycle–climate connection and over the ocean’s capacity to absorb CO2. Some scientists believe that the oceans can absorb one to two billion tons of CO2 a year, about the amount the world emitted in 1950. Until scientists can more accurately determine how much CO2 can be buffered by ocean processes, the extent and speed of disruption in the carbon supply remains unclear.
The Environment
Methane Methane (CH4) is a colorless gas found in trace (extremely small) amounts in the atmosphere. It is the primary component of natural gas—the gas trapped beneath the Earth’s crust that is mined and burned for energy. Methane is an important component of greenhouse emissions, second only to CO2. (See Figure 3.5.) While there is less methane in the atmosphere, scientists believe that it may be much more effective at trapping heat in the atmosphere than CO2. During the 1900s methane’s concentration in the atmosphere more than doubled. Scientists generally attribute those increases to human sources, such as landfills, natural gas systems, agricultural activities, coal mining, and wastewater treatment.
As shown in Table 3.1, methane emissions from landfills, natural gas systems, and enteric fermentation accounted for two-thirds of total U.S. emissions in 2003. Enteric fermentation is a natural digestive process that occurs in domestic animals, such as cattle and sheep, and releases methane. Growing markets for beef and milk products are driving a booming livestock business. Humans contribute to atmospheric methane levels through activities that concentrate and magnify biological decomposition. This includes landfilling organic materials, raising livestock, cultivating rice in paddies, collecting sewage for treatment, and constructing artificial wetlands. In addition, methane is a byproduct of the combustion of biomass and is vented (intentionally and unintentionally) during the extraction and processing of fossil fuels. It also results from incomplete combustion of fossil fuels. Methane is believed to break down in the atmosphere after approximately nine to fifteen years. Ozone Ozone (O3) is a blue-tinted gas naturally found in Earth’s atmosphere. Approximately 90% of the ozone is in the stratosphere, the atmospheric layer lying above the troposphere. The so-called ozone layer absorbs harmful ultraviolet radiation from the Sun to prevent it from reaching the ground. Scientists believe that stratospheric ozone is being depleted by the introduction of certain industrial chemicals, primarily chlorine and bromine. This depletion has serious consequences in terms of ultraviolet radiation effects and probably lessens the warmth-trapping capability of ozone at this level.
Tropospheric ozone is the primary component in smog, a potent air pollutant. It is not emitted directly into the air but forms due to complex reactions that occur when other air pollutants, primarily volatile organic compounds and nitrogen oxides, are present. Primary sources of these ozone precursors include industrial chemical processes and fossil fuel combustion. The atmospheric lifetime of ozone ranges from weeks to months. The Enhanced Greenhouse Effect and Climate Change
39
TABLE 3.1
Trends in U.S. greenhouse gas emissions and sinks, in teragrams of carbon dioxide equivalents (Teragrams CO2 Equivalent), 1990 and 1997–2003 Gas/source
1990
1997
1998
1999
2000
2001
2002
2003
CO2
5,009.6
5,580.0
5,607.2
5,678.0
5,858.2
5,744.8
5,796.8
5,841.5
Fossil fuel combustion Non-energy use of fuels Iron and steel production Cement manufacture Waste combustion Ammonia production and urea application Lime manufacture Natural gas flaring Limestone and dolomite use Aluminum production Soda ash manufacture and consumption Petrochemical production Titanium dioxide production Phosphoric acid production Ferroalloys Carbon dioxide consumption Land-use change and forestry (sinks)a International bunker fuelsb Biomass combustionb
4,711.7 108.0 85.4 33.3 10.9
5,263.2 120.3 71.9 38.3 17.8
5,278.7 135.4 67.4 39.2 17.1
5,345.9 141.6 64.4 40.0 17.6
5,545.1 124.7 65.7 41.2 18.0
5,448.0 120.1 58.9 41.4 18.8
5,501.4 118.8 55.1 42.9 18.8
5,551.6 118.0 53.8 43.0 18.8
19.3 11.2 5.8 5.5 6.3
20.7 13.7 7.9 7.2 5.6
21.9 13.9 6.6 7.4 5.8
20.6 13.5 6.9 8.1 5.9
19.6 13.3 5.8 6.0 5.7
16.7 12.8 6.1 5.7 4.1
18.6 12.3 6.2 5.9 4.2
15.6 13.0 6.0 4.7 4.2
4.1 2.2 1.3 1.5 2.0 0.9
4.4 2.9 1.8 1.5 2.0 0.8
4.3 3.0 1.8 1.6 2.0 0.9
4.2 3.1 1.9 1.5 2.0 0.8
4.2 3.0 1.9 1.4 1.7 1.0
4.1 2.8 1.9 1.3 1.3 0.8
4.1 2.9 2.0 1.3 1.2 1.0
4.1 2.8 2.0 1.4 1.4 1.3
(930.0) 109.9 233.2
(881.0) 114.6 217.2
(826.1) 105.3 222.3
(822.4) 101.4 226.8
(826.9) 97.9 200.5
(826.5) 89.5 207.2
(828.0) 84.2 216.8
(1,042.0) 113.5 216.7
CH4
605.3
579.5
569.1
557.3
554.2
546.8
542.5
545.0
Landfills Natural gas systems Enteric fermentation Coal mining Manure management Wastewater treatment Petroleum systems Rice cultivation Stationary sources Abandoned coal mines Mobile sources Petrochemical production Iron and steel production Agricultural residue burning Silicon carbide production International bunker fuelsb
172.2 128.3 117.9 81.9 31.2 24.8 20.0 7.1 7.8 6.1 4.8 1.2 1.3 0.7 0.2
147.4 133.6 118.3 62.6 36.4 31.7 18.8 7.5 7.4 8.1 4.0 1.6 1.3 0.8 0.1
138.5 131.8 116.7 62.8 38.8 32.6 18.5 7.9 6.9 7.2 3.9 1.7 1.2 0.8 0.2
134.0 127.4 116.8 58.9 38.8 33.6 17.8 8.3 7.1 7.3 3.6 1.7 1.2 0.8 0.1
130.7 132.1 115.6 56.2 38.1 34.3 17.6 7.5 7.3 7.7 3.4 1.7 1.2 0.8 0.1
126.2 131.8 114.5 55.6 38.9 34.7 17.4 7.6 6.7 6.9 3.1 1.4 1.1 0.8 0.1
126.8 130.6 114.6 52.4 39.3 35.8 17.1 6.8 6.4 6.4 2.9 1.5 1.0 0.7 0.1
131.2 125.9 115.0 53.8 39.1 36.8 17.1 6.9 6.7 6.4 2.7 1.5 1.0 0.8 0.1
N2O
382.0
396.3
407.8
382.1
401.9
385.8
380.5
376.7
Agricultural soil management Mobile sources Manure management Human sewage Nitric acid Stationary sources Settlements remaining settlements Adipic acid N2O product usage Waste combustion Agricultural residue burning Forest land remaining forest land International bunker fuelsb
253.0 43.7 16.3 13.0 17.8 12.3
252.0 55.2 17.3 14.7 21.2 13.5
267.7 55.3 17.4 15.0 20.9 13.4
243.4 54.6 17.4 15.4 20.1 13.5
263.9 53.2 17.8 15.6 19.6 14.0
257.1 49.0 18.0 15.6 15.9 13.5
252.6 45.6 17.9 15.7 17.2 13.5
253.5 42.1 17.5 15.9 15.8 13.8
5.5 15.2 4.3 0.4 0.4
6.1 10.3 4.8 0.4 0.4
6.1 6.0 4.8 0.3 0.5
6.2 5.5 4.8 0.3 0.4
6.0 6.0 4.8 0.4 0.5
5.8 4.9 4.8 0.4 0.5
6.0 5.9 4.8 0.5 0.4
6.0 6.0 4.8 0.5 0.4
0.1 1.0
0.3 1.0
0.4 1.0
0.5 0.9
0.4 0.9
0.4 0.9
0.4 0.8
0.4 as
Nitrous Oxide
Nitrous oxide (N2O) is a colorless gas found in trace amounts in the atmosphere. Soils naturally release the gas as a result of bacterial processes called nitrification and denitrification. Soils found in tropical areas and moist forests are believed to be the largest contributors. Oxygen-poor waters and sediments in oceans and estuaries are also natural sources. Although N2O makes up a much smaller portion of greenhouse gases than CO2, it is much more (perhaps 310 40
The Enhanced Greenhouse Effect and Climate Change
times more) powerful than CO2 at trapping heat. Agriculture is and has been the major source of N2O emissions in the United States, followed by energy and industrial sources. As shown in Table 3.1 agricultural soil management accounted for 67% of total N2O emissions during 2003. Humans have significantly increased the release of nitrous oxide from soils through use of nitrogen-rich fertilizers. Other anthropogenic sources include combustion of fossil fuels and biomass, wastewater treatment, The Environment
TABLE 3.1
Trends in U.S. greenhouse gas emissions and sinks, in teragrams of carbon dioxide equivalents (Teragrams CO2 Equivalent), 1990 and 1997–2003 [CONTINUED] 1997
1998
1999
2000
2001
2002
2003
HFCs, PFCs, and SF6
Gas/source
1990 91.2
121.7
135.7
134.8
138.9
129.5
138.3
137.0
Substitution of ozone depleting substances Electrical transmission and distribution HCFC-22 production Semiconductor manufacture Aluminum production Magnesium production and processing
0.4 29.2 35.0 2.9 18.3 5.4
46.5 21.7 30.0 6.3 11.0 6.3
56.6 17.1 40.1 7.1 9.1 5.8
65.8 16.4 30.4 7.2 9.0 6.0
75.0 15.6 29.8 6.3 9.0 3.2
83.3 15.4 19.8 4.5 4.0 2.6
91.5 14.7 19.8 4.4 5.2 2.6
99.5 14.1 12.3 4.3 3.8 3.0
6,088.1
6,677.5
6,719.7
6,752.2
6,953.2
6,806.9
6,858.1
6,900.2
5,046.1
5,747.5
5,838.8
5,926.1
6,130.8
5,980.1
6,031.6
6,072.2
Total Net emissions (sources and sinks)
Does not exceed 0.05 Tg CO2 Eq. a Sinks are only included in net emissions total, and are based partially on projected activity data. Parentheses indicate negative values (or sequestration). b Emissions from international bunker fuels and biomass combustion are not included in totals. Note: Totals may not sum due to independent rounding. SOURCE: “Table ES-2. Recent Trends in U.S. Greenhouse Gas Emissions and Sinks (Tg CO2 Eq.),” in Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2003, U.S. Environmental Protection Agency, Washington, DC, April 15, 2005, http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/ RAMR69V4ZS/$File/05_complete_report.pdf (accessed August 4, 2005)
FIGURE 3.5
FIGURE 3.4
The effect of forests on carbon dioxide concentrations
Greenhouse gas emissions, by gas, 2003
CO2
HFCs, PFCs & SF6 2%
Sunlight O2
H2O
Chlorophyll
As plants and trees grow, photosynthesis— involving the interaction of sunlight, chlorophyll in green leaves, carbon dioxide (CO2) and water (H2O)—results in a net removal of CO2 from the air and the release of oxygen (O2) as a by-product. Also, moisture is released to the air through evapotranspiration.
CH4 8%
CO2 85%
H2O
CO2
N2O 5%
O2 When forests die and decay, or are burned, the biomass is oxidized and CO2 is returned to the air.
SOURCE: Adapted from “Figure ES-4, 2003 Greenhouse Gas Emissions by Gas,” in Inventory of U.S Greenhouse Gas Emissions and Sinks: 1990–2003, U.S. Environmental Protection Agency, Washington, DC, April 15, 2005, http://yosemite.epa.gov/oar/globalwarming.nsf/ UniqueKeyLookup/RAMR69V4ZS/$File/05_complete_report.pdf accessed August 4, 2005)
Engineered Gases “Figure 2a” and “Figure 2b,” in Biosphere, NASA Facts, National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, MD, April 1998
SOURCE:
and certain manufacturing processes, particularly the production of nylon and nitric acid. Nitrous oxide has an atmospheric lifetime of approximately 120 years. The Environment
Engineered gases are synthetic gases specially designed for modern industrial and commercial purposes. They are also known as ‘‘high GWP gases,’’ because they have a high global warming potential compared with carbon dioxide. They include hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6). The Enhanced Greenhouse Effect and Climate Change
41
PFCs are a class of chemicals containing fluorine and carbon. They also are increasingly used by industry as substitutes for ozone-depleting CFCs. SF6 is a colorless, odorless gas commonly used as an insulating medium in electrical equipment and as an etchant (an etching agent) in the semiconductor industry. Although emissions of these chemicals are very small in comparison with other greenhouse gases, they are of particular concern because of their long life in the atmosphere. PFCs and SF6 have atmospheric lifetimes of thousands of years and are actually far more potent greenhouse gases than CO2 per unit of molecular weight. Indirect Greenhouse Gases There are several gases considered indirect greenhouse gases because of their effects on the chemical environment of the atmosphere. These gases include reactive nitrogen oxides (NOx), carbon monoxide (CO), and volatile organic compounds (VOCs). Most of their emissions are from anthropogenic sources, primarily combustion and industrial processes. CHANGES IN THE ATMOSPHERE Earth’s atmosphere was first compared to a glass vessel in 1827 by the French mathematician Jean-Baptiste Fourier. In the 1850s British physicist John Tyndall tried to measure the heat-trapping properties of various components of the atmosphere. By the 1890s scientists had concluded that the great increase in combustion in the Industrial Revolution had the potential to change the atmosphere’s load of CO2. In 1896 the Swedish chemist Svante Arrhenius made the revolutionary suggestion that human activities could actually disrupt this delicate balance. He theorized that the rapid increase in the use of coal that came with the Industrial Revolution could increase CO2 concentrations and cause a gradual rise in temperatures. For almost six decades his theory stirred little interest.
In 1957 studies at the Scripps Institute of Oceanography in California suggested that, indeed, half the CO2 released by industry was being permanently trapped in the atmosphere. The studies showed that atmospheric concentrations of CO2 in the previous thirty years were greater than in the previous two centuries and that the gas had reached its highest level in 160,000 years. Scientists can estimate the makeup of Earth’s atmosphere long ago by testing air pockets in ice sheets believed to have formed around the same time. 42
The Enhanced Greenhouse Effect and Climate Change
FIGURE 3.6
Trend in global average carbon dioxide concentration Global average
370 CO2 (ppm)
HFCs are chemicals that contain hydrogen, fluorine, and carbon. They are popular substitutes in industrial applications for chlorofluorocarbons (CFCs). CFCs are commonly used in cooling equipment, fire extinguishers, as propellants, and for other uses. They are one of the culprits blamed for depletion of stratospheric ozone.
360 350 340
81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 Year SOURCE: Adapted from “Carbon Dioxide Measurements: NOAA CMDL Carbon Cycle Greenhouse Gases,” in Carbon Cycle Greenhouse Gases Figures, U.S. Department of Commerce, National Oceanic and Atmospheric Administrations, Climate Monitoring and Diagnostics Laboratory, Boulder, CO, May 2004, http://www.cmdl.noaa.gov/ gallery/ccgg_figures/co2trend_global (accessed August 4, 2005)
Findings in the 1980s and 1990s provided more disturbing evidence of atmospheric changes. Scientists detected increases in other, even more potent gases that contribute to the greenhouse effect, notably chlorofluorocarbons (CFC11 and -12), methane, nitrous oxide (N2O), and halocarbons (CFCs, methyl chloroform, and hydrochlorofluorocarbons). In May 2005 the EPA reported that the average atmospheric concentration of CO2 increased from 280 parts per million (ppm) in preindustrial times to 372.3 ppm in 2003. Likewise, the average methane level increased from approximately 700 parts per billion (ppb) in the year 1750 to a value of 1,750 ppb in the early 2000s. Increases in these gases over the past two decades are shown in Figure 3.6 for carbon dioxide and Figure 3.7 for methane. These data were collected by the National Oceanic and Atmospheric Administration (NOAA) from its Climate Monitoring and Diagnostics Laboratory (CMDL). The CMDL is headquartered in Boulder, Colorado, and operates observatories in Barrow, Alaska; Trinidad Head, California; Mauna Loa, Hawaii; Samoa; and the South Pole. The agency compiles longterm records on air quality and solar radiation data. Scientists agree that atmospheric concentrations of gases known to play a role in the natural greenhouse effect are increasing. There is still disagreement about whether this increase has affected global temperatures. A RECENT WARMING TREND Scientists do not know how much the global temperature has varied on its own in the relatively recent past (about one thousand years). Temperature records The Environment
FIGURE 3.7
FIGURE 3.8
Global average methane concentrations, 1984–2003
Trend in annual global mean temperatures, 1880–2004
Global average Global land ⴙ ocean surface Annual mean
.6
1,725 1,700 1,675 1,650 1,625
84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03
Temperature anomaly (˚C)
CH4 (parts per billion)
1,750 5-year mean
.4
.2
.0 .2
Year Note: Global average atmospheric methane mixing ratios (black line) determined using measurements from the National Oceanic & Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) cooperative air sampling network. The gray line represents the long-term trend. SOURCE: Adapted from “Methane Measurements: NOAA CMDL Carbon Cycle Greenhouse Gases,” in Carbon Cycle Greenhouse Gases Figures, U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Climate Monitoring and Diagnostics Laboratory, Boulder, CO, May 2004, http://www.cmdl.noaa.gov/gallery/ccgg _figures/ch4trend_global (accessed August 4, 2005)
based on thermometers go back only about 150 years. Investigators have turned, therefore, to ‘‘proxy’’ (indirect) means of measuring past temperatures. These methods include chemical evidence of climatic change contained in fossils, corals, ancient ice, and growth rings in trees. In 1998 Drs. Michael E. Mann and Raymond S. Bradley of the University of Massachusetts at Amherst and Dr. Malcolm K. Hughes of the University of Arizona at Tucson surveyed proxy evidence of temperatures in the Northern Hemisphere since 1400. They discovered that the twentieth century was the warmest century of the past six hundred years. They concluded that the warming trend seems to be closely connected to the emission of greenhouse gases by humans. Some experts, however, question whether studies of proxy evidence will ever be reliable enough to yield valuable information on global warming. Three international agencies have compiled longterm data on surface temperatures—the British Meteorological Office in Bracknell, United Kingdom, the National Climatic Data Center in Asheville, North Carolina, and the National Aeronautics and Space Administration (NASA) Goddard Institute for Space Studies in New York. Temperature measurements from these organizations reported that the 1990s were the warmest decade of the twentieth century and the warmest decade since humans began measuring temperatures in the mid-nineteenth century. The average global surface The Environment
.4 1880
1900
1920
1940
1960
1980
2000
Year SOURCE: Adapted from “Annual Mean Temperature Anomalies [Base Period 1951–80] Global Land & Ocean Surface,” in Datasets & Images: GISS Surface Temperature Analysis: Global Temperature Trends: 2004 Summation, National Aeronautics and Space Administration, Goddard Institute for Space Studies, New York, NY, May 19, 2005, http://data .giss.nasa.gov/gistemp/2004/Fig.1.pdf (accessed August 4, 2005)
temperature was approximately 1 degree Fahrenheit warmer than at the turn of the twentieth century, and this rise increased more rapidly since 1980. According to NASA, the 1998 meteorological year was the warmest year recorded since the late 1800s. (See Figure 3.8.) A meteorological year runs from the beginning of winter to the end of autumn. The second-, third-, and fourth-warmest years were 2002, 2003, and 2004, respectively. There has been a strong warming trend over the past three decades. Scientists do not know if this trend is part of a natural climate cycle or the result of an enhanced greenhouse effect. OTHER INFLUENCES ON EARTH’S CLIMATE
Besides the greenhouse effect there are many other natural and anthropogenic factors that affect Earth’s climate. Some of the major factors are discussed below. The Effects of Clouds on Global Temperature
Surprisingly little is known about clouds—where they occur, their role in energy and water transfer, and their ability to reflect solar heat. Earth’s climate maintains a balance between the energy that reaches Earth from the Sun and the energy that radiates back from Earth into space. Scientists refer to this as Earth’s ‘‘radiation budget.’’ The components of Earth’s system are the planet’s surface, atmosphere, and clouds. The Enhanced Greenhouse Effect and Climate Change
43
Different parts of Earth have different capacities to reflect solar energy. Oceans and rain forests reflect only a small portion of the Sun’s energy. Deserts and clouds, on the other hand, reflect a large portion of solar energy. A cloud reflects more radiation back into space than the surface would in the absence of clouds. An increase in cloudiness can also act like the panels on a greenhouse roof. NASA’s Earth Science Enterprise is a satellite-based program that includes numerous scientific studies of clouds. These studies have revealed that: • The effect of clouds on climate depends on the balance between the incoming solar radiation and the absorption of Earth’s outgoing radiation. • Low clouds have a cooling effect because they are optically thicker and reflect much of the incoming solar radiation out to space. • High, thin cirrus clouds have a warming effect because they transmit most of the incoming solar radiation while also trapping some of Earth’s radiation and radiating it back to the surface. • Deep convective clouds have neither a warming nor a cooling effect because their reflective and absorptive abilities cancel one another. Another Possible Warming Culprit—Solar Cycles Scientists have known for centuries that the Sun goes through cycles; it has seasons, storms, and rhythms of activity with sunspots and flares appearing in cycles of roughly eleven years. Some scientists contend that these factors play a role in climate change on Earth. Some research, though sketchy and controversial, suggests that the Sun’s variability could account for some, if not all, of global warming to date. The biggest correlation occurred centuries ago—between 1640 and 1720—when sunspot activity fell sharply and Earth cooled about 2 degrees Fahrenheit. (The Sun is brighter when sunspots appear and dimmer when they disappear.) The Effects of the Oceans on Temperature Oceans have a profound effect on global temperature, because of their huge capacity to store heat and because they can moderate levels of atmospheric gases. Covering more than 70% of Earth and holding 97% of the water on the planet’s surface, oceans function as huge reservoirs of heat. Ocean currents transport this stored heat and dissolved gases so that different areas of the world serve as either sources or sinks (repositories) for these components. While scientists know a great deal about oceanic and air circulation, they are less certain about the ocean’s ability to store additional CO2 or about how much heat it will absorb.
The top eight feet of the oceans hold as much heat as Earth’s entire atmosphere. As ocean waters circulate 44
The Enhanced Greenhouse Effect and Climate Change
globally, heat is transferred from low altitudes to high altitudes, from north to south, and vertically from surface to deep oceans and back. But how is this heat apportioned? If heat is able to circulate through the entire oceanic depth range, the process could take centuries and the world’s oceans could serve to buffer or delay global warming. Researchers are working to determine that possibility, but it remains one of many unanswered questions. The Effects of El Nin˜o and La Nin˜a For centuries fishermen in the Pacific Ocean off the coast of South America have known about the phenomenon called El Nin˜o. Every three to five years, during December and January, fish in those waters virtually vanish, bringing fishing to a standstill. Fishermen gave this occurrence the name ‘‘El Nin˜o,’’ which means ‘‘the Child,’’ because it occurs around the celebration of the birth of Jesus, the Christ child. Although originating in the Pacific, the effects of El Nin˜o are felt around the world. Computers, satellites, and improved data gathering have found that the El Nin˜o phenomenon has been responsible for drastic climate change.
An El Nin˜o occurs because of interactions between atmospheric winds and sea surfaces. In normal years, trade winds blow from east to west across the eastern Pacific. They drag the surface waters westward across the ocean, causing deeper, cold waters to rise to the surface. This upwelling of deep ocean waters carries nutrients from the bottom of the ocean that feed fish populations in the upper waters. In an El Nin˜o the westward movement of waters weakens, causing the upwelling of deep waters to cease. The resulting warming of the ocean waters further weakens trade winds and strengthens El Nin˜o. Without upwelling, the nutrient content of deep waters is diminished, which in turn causes the depletion of fish populations. The warm waters that normally lie in the western waters of the Pacific shift eastward. This turbulence creates eastward weather conditions, in which towering cumulus clouds reach high into the atmosphere with strong vertical forces and the weakening of normal east-to-west trade winds. An El Nin˜o is the warm phase of a phenomenon known as ENSO (El Nin˜o/Southern Oscillation), which can also include a cold phase known as a La Nin˜a. According to the NOAA (http://www.pmel.noaa.gov/ tao/elnino/el-nino-story.html#recent), El Nin˜os occurred during 1986–1987, 1991–1992, 1993, 1994, and 1997– 1998. These events disrupted the ocean-atmosphere system in the Pacific Ocean with subsequent effects on weather around the planet. The NOAA notes that El Nin˜os result in increased rainfall and flooding in the southern United States and parts of South America and drought conditions in the western Pacific region. The Environment
FIGURE 3.9
Changes in solar radiation caused by volcanic eruptions, 1958–2003 1
0
Percent change
1
Agung
2 Pinatubo 3 EI Chichon 4 Monthly means with 5 month smoother 5 1958
1963
1968
1973
1978
1983
1988
1993
1998
2003
Year SOURCE: “Net Solar Radiation at Mauna Loa Observatory, Relative to 1958, Showing the Effects of Major Volcanic Eruptions. Annual Variations Are Due to Transport of Asian Dust and Air Pollution to Hawaii,” in Climate Forcing, U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Climate Monitoring and Diagnostics Laboratory, Boulder, CO, undated, http://www.cmdl.noaa.gov/climate.html (accessed August 4, 2005)
The Effects of Volcanic Activity on Temperature
Volcanic activity, such as the 1991 eruption of the Mount Pinatubo volcano in the Philippines, can temporarily reduce the amount of solar radiation reaching the Earth. Volcanoes spew vast quantities of particles and gases into the atmosphere, including sulfur dioxide (SO2) that combines with water to form tiny supercooled droplets. The droplets create a long-lasting global haze that reflects and scatters sunlight, reducing energy from the Sun and preventing its rays from heating the Earth, thereby causing the planet to cool. Figure 3.9 is a graph compiled by the CMDL based on data from the Mauna Loa, Hawaii, observatory. It shows how solar radiation was dramatically reduced by the Pinatubo eruption. The eruption reduced solar radiation by more than 3% compared to the baseline amount occurring in 1958. This effect also happened in 1982, when eruption of the El Chichon volcano in Mexico depressed global temperatures for about four years. In 1815 a major eruption of the Tambora volcano in Indonesia produced serious weather-related disruptions, such as crop-killing summer frosts in the United States and Canada. It became known as the ‘‘year without a summer.’’ On the other hand, for several years following the Tambora eruption people around the world commented on the beautiful sunsets, which were caused by the suspension of volcano-related particulate matter in the atmosphere. The Environment
The Effects of Aerosols Aerosols are extremely tiny particles and/or liquid droplets that disperse in the atmosphere. Primary natural sources include volcanoes, forest fires, soil, sand, dust, sea salt, and scores of biological organisms and refuse (bacteria, pollen, dead skin cells, dander, spores, fungi, marine plankton, etc.). Aerosols are also produced by numerous fuel combustion and industrial processes.
Aerosols in the atmosphere scatter and absorb radiation. They also modify the formation and water content of clouds. Aerosols linger for only weeks to months in the troposphere and are returned to Earth in precipitation. Although their exact effects on climate are not well understood, it is believed that aerosols have a local and temporary cooling effect on the atmosphere. THE INTERNATIONAL COMMUNITY TAKES ACTION The World Meteorology Organization Speaks Up At the world’s first ecological summit, the 1972 Stockholm Conference, climate change was not even listed among the threats to the environment. Many earth scientists and meteorologists, however, were becoming alarmed about growing evidence supporting the notion of an enhanced greenhouse effect. In 1979 the World Meteorological Organization (WMO) established its World Climate Programme to collect data and research The Enhanced Greenhouse Effect and Climate Change
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TABLE 3.2
International treaties related to climate change 1979
1985
1988 1990 1992
1994 1995
1996 1997 2001 2005
SOURCE:
World Meteorological Organization (WMO) holds first World Climate Conference and establishes World Climate Programme to collect data and research the earth’s climate system. The WMO, United Nations Environment Program (UNEP), and International Council for Science (ICSU) hold conference on the role of carbon dioxide in climate variations. WMO and UNEP establish the Intergovernmental Panel on Climate Change (IPCC). IPCC publishes First Assessment Report. IPCC publishes Supplement to First Assessment Report. United Nations adopts United Nations Framework Convention on Climate Change (UNFCCC), and presents it for signatures at the 1992 Earth Summit in Rio de Janeiro. IPCC publishes Special Report. IPCC publishes Second Assessment Report. First Conference of the Parties to the UNFCCC (COP-1) is held in Berlin. The Berlin Mandate to the UNFCCC is adopted. COP-2 is held in Vienna. COP-3 is held in Kyoto, Japan. The Kyoto Protocol to the UNFCCC is adopted. IPCC publishes Third Assessment Report. Kyoto Protocol to the UNFCCC goes into effect. COP-11 and First Meeting of the Parties to the Kyoto Protocol (MOP-1) to be held in December 2005.
Created by Kim Masters Evans for Thomson Gale, 2005
the complex components of the Earth’s climate system. The WMO is a nongovernmental agency under the United Nations Environment Programme (UNEP). At a 1979 conference the WMO acknowledged that ‘‘man’s activities on Earth may cause significant extended regional and even global changes of climate’’ (16 Years of Scientific Assessment in Support of the Climate Convention, Intergovernmental Panel on Climate Change, Geneva, Switzerland, December 2004). This was the first major step in the response of the international community to the threat of global warming. Other major milestones are listed in Table 3.2. In 1985 representatives of the WMO, UNEP, and the International Council for Science met in Austria to discuss the role of carbon dioxide and other greenhouse gases in climate change. They predicted that rising levels of these gases would cause an increase in the global temperature during the first half of the twenty-first century. The Intergovernmental Panel on Climate Change
In 1988 the WMO and UNEP established the Intergovernmental Panel on Climate Change (IPCC). The IPCC set up three working groups to assess available scientific information on climate change, estimate the expected impacts of climate change, and formulate strategies for responding to the problem. The first IPCC assessment report was issued in 1990. Several signs of climate change were noted by the IPCC in its report: 46
The Enhanced Greenhouse Effect and Climate Change
• The average warm-season temperature in Alaska had risen nearly three degrees Fahrenheit in the previous fifty years. • Glaciers had generally receded and become thinner on average by about thirty feet in the previous forty years. • There was about 5% less sea ice in the Bering Sea than in the 1950s. • Permafrost was thawing, causing the ground to subside, opening holes in roads, producing landslides and erosion, threatening roads and bridges, and causing local floods. • Ice cellars in northern villages had thawed and become useless. • More precipitation was falling as rain than snow in northern areas, and the snow was melting faster, causing more running and standing water. The IPCC report was the most comprehensive summary of climate-change science to date. It represented the input of approximately four hundred international scientists and acknowledged that global warming was a real threat to the Earth’s climate. Using computer models, IPCC researchers predicted that the global mean temperature would increase by 0.3 degrees Celsius (0.54 degrees Fahrenheit) each decade during the twenty-first century. They also predicted that the global mean sea level would rise by six centimeters (2.4 inches) per decade. However, the scientists noted that there were a number of uncertainties in their assumptions based on lack of data. The United Nations Framework Convention on Climate Change (1992)
In 1992 the United Nations adopted the United Nations Framework Convention on Climate Change (UNFCCC). The UNFCCC was an international agreement presented for signatures at the 1992 Earth Summit in Rio de Janeiro. The stated objective of the agreement was as follows: Stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. Such a level should be achieved within a time-frame sufficient to allow ecosystems to adapt naturally to climate change, to ensure that food production is not threatened and to enable economic development to proceed in a sustainable manner.
The agreement set specific goals for developed countries to track and publish detailed inventories of their greenhouse gas emissions. These countries were also expected by the year 2000 to reduce emissions to 1990 levels. The Environment
The UNFCCC was signed by 143 countries. Many environmentalists criticized the treaty as too weak because it did not establish specific targets that governments must meet. The treaty did not include specific targets mainly because then-President George H. W. Bush, representing the United States, refused to accept them. President Clinton signed the treaty in 1994. Critics, however, complain that adherence to the measures has been disappointing even among those nations that originally signed. Supporters of a global warming strategy advocate limiting the emissions of the four main greenhouse gases and recommend a gradual transition away from fossil fuels, which currently provide about three-quarters of the world’s energy. In 1995, 120 parties to the global warming treaty met in Berlin in what is known as the Berlin Mandate to determine the success of existing treaties and to embark on discussions of emissions after 2000. Differences persisted along north–south lines, with developing countries making essentially a moral argument for requiring more of the richer nations. They pointed out that the richer nations are responsible for most of the pollution. The Berlin talks essentially failed to endorse binding timetables for reductions in greenhouse gases. A Landmark Judgment—The 1995 IPCC Report
In 1995 the IPCC reassessed the state of knowledge about climate change. The panel reaffirmed its earlier conclusions and updated its forecasts, predicting that, if no further action is taken to curb emissions of greenhouse gases, temperatures would increase 1.44 degrees to 6.30 degrees Fahrenheit by 2100. The panel concluded that the evidence suggested a human influence on global climate. The cautiously worded statement was a compromise following intense discussions. Nonetheless, it was a landmark conclusion because the panel, until then, had maintained that global warming and climate changes could have been the result of natural variability.
TABLE 3.3
Greenhouse gas emission reduction targets under the Kyoto Protocol
Country Australia Austria (R) Belgium (R) Bulgaria (R) Canada (R) Croatia Czech Republic (R) Denmark (R) Estonia (R) European Community (R)* Finland (R) France (R) Germany (R) Greece (R) Hungary (R) Iceland (R) Ireland (R) Italy (R) Japan(R) Latvia (R) Liechtenstein Lithuania (R) Luxembourg (R) Monaco Netherlands (R) New Zealand (R) Norway (R) Poland (R) Portugal (R) Romania (R) Russia Slovakia (R) Slovenia (R) Spain (R) Sweden (R) Switzerland (R) Ukraine United Kingdom (R) United States
Reduction target (percent) 8.0 13.0 7.5 8.0 6.0 5.0 8.0 21.0 8.0 8.0 0.0 0.0 21.0 25.0 6.0 10.0 13.0 6.5 6.0 8.0 8.0 8.0 28.0 8.0 6.0 0.0 1.0 6.0 27.0 8.0 0.0 8.0 8.0 15.0 4.0 8.0 0.0 12.5 7.0
Notes: (R)Country has ratified, accepted, approved, or acceded to the Kyoto Protocol. *European Union member countries renegotiated their individual targets under the EU Shared Burden Agreement, which was agreed to in 1998 and reaffirmed in the ratification of the Kyoto Protocol in 2002. SOURCE: “Table 17. Quantified Emissions Reduction Targets Under the Kyoto Protocol by Country,” in International Energy Outlook: 2004, U.S. Department of Energy, Energy Information Administration, Office of Integrated Analysis and Forecasting, Washington, DC, April 2004, http:// www.eia.doe.gov/oiaf/archive/ieo04/environmental_tables.html (accessed August 4, 2005)
The Kyoto Protocol (1997)
In December 1997 delegates from 166 countries met in Kyoto, Japan, at the UN Climate Change Conference to negotiate actions to reduce global warming. Some developed nations, including the United States, wanted to require all countries to reduce their emissions. Developing countries, however, felt the industrialized nations had caused, and were still causing, most global warming and therefore should bear the brunt of economic sacrifices to clean up the environment. Even within the industrialized community, the European Union criticized the United States for lagging behind in reducing emissions, as it had previously pledged. The Environment
The conference developed an agreement known as the Kyoto Protocol to the UNFCCC. Different targets for different countries, tailored to their economic and social circumstances, were used to get around the impasse between nations. (See Table 3.3.) Overall the treaty is expected to effect a total reduction in greenhouse gas emissions of at least 5% during the commitment period of 2008–12 compared with 1990 levels. The treaty also set up an emission trading system that allowed countries exceeding their pollution limits to purchase on an open market ‘‘credits’’ from countries that pollute less. This provision was viewed as necessary to The Enhanced Greenhouse Effect and Climate Change
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U.S. congressional approval. The developing nations feared that such a trading system would allow rich countries to buy their way into compliance rather than make unpopular emissions cuts. Enforcement mechanisms were not agreed to, nor did developing nations commit to binding participation.
FIGURE 3.10
World carbon dioxide emissions from the consumption and flaring of fossil fuels, 2003
The treaty was set up to take effect when two conditions were met: India 4%
• It was ratified by at least fifty-five countries. • The ratifying countries accounted for at least 55% of carbon dioxide emissions based on 1990 levels. In March 2001 President George W. Bush indicated that the United States would not ratify the treaty because it would cost an estimated $400 billion and 4.9 million jobs to comply. In 2002 the treaty was ratified by major entities including the European Union, Japan, China, Canada, and India. It came into effect in February 2005 following ratification by Russia in late 2004. As of May 2005 the treaty had been ratified by more than 150 nations. The notable exceptions are the United States and Australia. The IPCC’s 2001 Assessment Report The IPCC issued its third assessment report in 2001. It actually comprised four reports: Climate Change 2001: The Scientific Basis, Climate Change 2001: Impacts, Adaptation and Vulnerability, Climate Change 2001: Mitigation, and Climate Change 2001: The Synthesis Report. The IPCC’s assessment covered the adaptability and vulnerability of North America to climate change impacts likely to occur from global warming. Among the suggested possible effects of global warming were:
• Expansion of some diseases in North America • In coastal areas, increased erosion, flooding, and loss of wetlands • Risk to ‘‘unique natural ecosystems’’ • Changes in seasonal snowmelts, which would have effects on water users and aquatic ecosystems • Some initial benefits for agriculture, but those benefits would decline over time and possibly ‘‘become a net loss’’ Next IPCC Update Due in 2007 The IPCC plans to publish its fourth major assessment report in 2007. At meetings held in Paris during 2003, seven themes were selected for focus in the report:
Japan 5%
Other Asia 10% United States 23% Canada 2%
China 14%
Mexico 2% Western Europe 15%
Africa 4% Middle East 5% Other Eastern Europe 6%
Central and South America 4%
Russia 6%
SOURCE: Adapted from “H.1co2 World Carbon Dioxide Emissions from the Consumption and Flaring of Fossil Fuels, 1980–2003,” in International Energy Annual: 2003, U.S. Department of Energy, Energy Information Administration, Office of Integrated Analysis and Forecasting, Washington, DC, July 2005, http://www.eia.doe.gov/pub/ international/iealf/tableh1co2.xls (accessed August 4, 2005)
• sustainable development • technology International Emissions of Greenhouse Gases The U.S. Department of Energy (DOE) released its International Energy Annual 2003 in July 2005. The report presents data collected on CO2 emissions related to fossil fuel use around the world. The United States was responsible for the largest portion (23%) of such emissions in 2003, followed by Western Europe (15%) and China (14%). (See Figure 3.10.) The western European countries responsible for most of that region’s CO2 emissions were Germany, the United Kingdom, Italy, and France.
The DOE predicts that CO2 emissions from developing countries could actually surpass those from industrialized countries before 2020. (See Figure 3.11.) This trend is attributed to increased use of coal in developing countries, particularly China and India, while developed countries rely increasingly on natural gas.
• risk and uncertainty • regional integration • water • key vulnerabilities • adaptation and mitigation 48
The Enhanced Greenhouse Effect and Climate Change
SOME RESEARCHERS QUESTION THE CAUSES OF GLOBAL WARMING Some scientists believe that major climate events should be viewed in terms of thousands of years, not just a century. A record of only the past century may indicate, The Environment
In 2000 a handful of scientists at the Oregon Institute of Science and Medicine began a drive to collect the signatures of other scientists on a petition reading in part: ‘‘There is no convincing scientific evidence that human release of carbon dioxide, methane, or other greenhouse gasses is causing or will, in the foreseeable future, cause catastrophic heating of the Earth’s atmosphere and disruption of the Earth’s climate. Moreover, there is substantial scientific evidence that increases in atmospheric carbon dioxide produce many beneficial effects on the natural plant and animal environments of the Earth.’’ As of June 2005 the so-called Petition Project claims to have collected more than 19,700 signatures, including 17,100 from scientists, mostly with advanced degrees.
FIGURE 3.11
World carbon dioxide emissions by region, 1990–2025
40,000
Total
EE/FSU
Industrialized countries
Developing countries
History
Projections
Million metric tons
30,000
20,000
10,000
0 1990
1995
2000
2005
2010
2015
2020
2025
Note: EE /FSU is Eastern Europe/former Soviet Union. SOURCE: “Figure 72. World Carbon Dioxide Emissions by Region, 1990–2025,” in International Energy Outlook: 2004, U.S. Department of Energy, Energy Information Administration, Office of Integrated Analysis and Forecasting, Washington, DC, April 2004, http://www.eia .doe.gov/oiaf/ieo/pdf/0484(2004).pdf (accessed August 4, 2005)
but not prove, that a major change has occurred. Is it caused by anthropogenic greenhouse gases, or is it natural variability? Among the claims of critics of global climate warming are: • Climate has been known to change dramatically within a relatively short period without any human influence. • Temperature readings already showed increased temperatures before CO2 levels rose significantly (before 1940). • Natural variations in climate may exceed any humancaused climate change. • Some of the increase in temperatures can be attributed to sunspot activity. • If warming should occur, it will not stress Earth; it may even have benefits, such as for agriculture, and may delay the next ice age. • Reducing emissions will raise energy prices, reduce gross domestic product, and produce job losses. • While clouds are crucial to climate predictions, so little is known about them that computer models cannot produce accurate predictions. The Environment
In October 2003 Anders Sivertsson, Kjell Aleklett, and Colin Campbell, researchers from the University of Uppsala in Sweden, disputed the IPCC’s predictions of extreme temperature change due to CO2 emissions. According to Andy Coghlan in his article ‘‘‘Too Little’ Oil for Global Warming’’ in the journal New Scientist (October 5, 2003, http://www.newscientist.com/article. ns?id=dn4216), the researchers noted that their data show that the world’s oil and gas supplies will be depleted long before atmospheric CO2 concentrations build to sufficient levels to make a major difference in Earth’s climate. THE UNITED STATES GOES ITS OWN WAY President George H. W. Bush’s administration (1989–1993) opposed precise deadlines for CO2 limits, arguing that the extent of the problem was too uncertain to justify painful economic measures. However, in 1989 the U.S. Global Change Research Program (USGCRP) was established and later authorized by Congress in the Global Change Research Act of 1990.
When President Bill Clinton took office in 1993, he joined the European Community in calling for overall emissions to be stabilized at 1990 levels by 2000, but this goal was not met. In October 1993 the United States, under the UNFCCC, released The Climate Change Action Plan detailing the nation’s response to climate change. The plan included a set of measures by both government and the private sector to lay a foundation for the nation’s participation in world response to the climate challenge. The Action Plan called for measures to reduce emissions for all greenhouse gases to 1990 levels by 2000. However, the U.S. economy grew at a more robust rate than anticipated, which led to increased emissions. Furthermore, the U.S. Congress did not provide full funding for the actions contained in the plan. Even though the United States had a comprehensive global warming program in place, Congress was reluctant to take steps to reduce emissions. However, the Clinton administration implemented some policies that did not The Enhanced Greenhouse Effect and Climate Change
49
require congressional approval. These included tax incentives and investments focusing on improving energy efficiency and renewable energy technologies, coordinating federal efforts to develop renewable fuels technology, and requiring all federal government agencies to reduce greenhouse gas emissions below 1990 levels by 2010. President Clinton also established the U.S. Climate Change Research Initiative to study areas of uncertainty about global climate change science and identify priorities for public investments. After President George W. Bush took office in 2001 he established a new cabinet-level management structure to oversee government investments in climate change science and technology. Both the U.S. Climate Change Research Initiative and the USGCRP were placed under the oversight of the Interagency Climate Change Science Program (CCSP), which reports integrated research sponsored by thirteen federal agencies. The CCSP is overseen by the Office of Science and Technology Policy, the Council on Environmental Quality, and the Office of Management and Budget. In June 2002 the George W. Bush administration released the third National Communication of the United States of America under the UNFCCC. The U.S. Climate Action Report—2002 (http://yosemite.epa.gov/ oar/globalwarming.nsf/content/ResourceCenterPublicationsUSClimateActionReport.html) acknowledged that greenhouse gases resulting from human activities were accumulating in the atmosphere and that they were causing air and ocean temperatures to increase. It did not rule out, however, the still-unknown role of natural variability in global warming. In addition, the report reiterated that the administration planned to reduce the nation’s greenhouse gas intensity by 18% over the following decade through a combination of existing regulations and voluntary, incentive-based measures. The report also projected levels of U.S. greenhouse gas emissions through the year 2020. As shown in Figure 3.12 these emissions are expected to increase by 32% between 2000 and 2020. However, the rate of increase per five-year interval is expected to decrease over the entire projection period. This slowdown is expected to be implemented by developing and implementing cleaner technologies and fuel substitutions. The vast majority of greenhouse gas emissions is expected to be carbon dioxide. The breakdown of these emissions by sector projected for 2020 is shown in Figure 3.13. Transportation is expected to account for 36% of all CO2 emissions in 2020. In 2000 transportation accounted for 32% of CO2 emissions. In July 2003 the reports: Strategic Plan Science Program and Science Program: Vision 50
CCSP published two major for the U.S. Climate Change The U.S. Climate Change for the Program and Highlights
The Enhanced Greenhouse Effect and Climate Change
FIGURE 3.12
Projected U.S. greenhouse gas emissions, by gas, 2000–20 [In teragrams of CO2 equivalent]
CO2
Methane
Nitrous oxides
High global warming potential gases
10,000 9,000 8,000 7,000 6,000 5,000 4,000 3,000 2,000 1,000
2000
2005
2010
2015
2020
Adapted from “Figure 5-2. U.S. Greenhouse Gas Emissions by Gas: 2000–2020,” in U.S. Climate Action Report—2002, U.S. Department of State, Washington, DC, May 2002, http://yosemite.epa .gov/oar/globalwarming.nsf/UniqueKeyLookup/SHSU5BNQ76/$File/ ch5.pdf (accessed August 4, 2005) SOURCE:
FIGURE 3.13
Projected sources of carbon dioxide emissions, 2020
Residential 18%
Commercial 18%
Transportation 36%
Industrial 28%
SOURCE: Adapted from “Table 5-3. U.S. CO2 Emissions by Sector and Source: 2000–2020 (Tg CO2),” in U.S. Climate Action Report—2002, U.S. Department of State, Washington, DC, May 2002, http://yosemite .epa.gov/oar/globalwarming.nsf/UniqueKeyLookup/SHSU5BNQ76/ $File/ch5.pdf (accessed August 4, 2005)
The Environment
of the Scientific Strategic Plan (both can be found at http://www.climatescience.gov/Library/stratplan2003). Together these documents outline the approach the CCSP plans to take to achieve its five main scientific goals: • Improve knowledge of the Earth’s past and present climate and environment, including its natural variability, and improve understanding of the causes of observed variability and change • Improve quantification of the forces bringing about changes in the Earth’s climate and related systems • Reduce uncertainty in projections of how the Earth’s climate and related systems may change in the future • Understand the sensitivity and adaptability of different natural and managed ecosystems and human systems to climate and related global changes • Explore the uses and identify the limits of evolving knowledge to manage risks and opportunities related to climate variability and change In May 2005 the Associated Press reported that the mayors of more than one hundred U.S. cities have agreed to abide by the provisions of the Kyoto Protocol in an attempt to lower greenhouse gas emissions in their cities by 2012. The effort was spearheaded by Seattle mayor Greg Nichols who received support from the mayors of other large cities, including New York City, Los Angeles, San Francisco, Boston, and Denver. U.S. GREENHOUSE GAS EMISSIONS Table 3.1 shows trends for the 1990s and early 2000s in U.S. greenhouse gas emissions and sinks (repositories, such as forests, that absorb and store carbon). As noted in Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2003, major sources of greenhouse gas emissions are listed below with their contributions to the overall 2003 emissions:
generated from combustion of fossil fuels (such as oil) for heating purposes. The EPA reported that CO2 accounted for 85% of greenhouse gas emissions in the United States in 2003. (See Figure 3.5.) Methane (CH4) was second with 8% of the total, followed by nitrous oxide (N2O) with 5% and other greenhouse gases, such as hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6), with 2%. POTENTIAL EFFECTS OF A WARMING CLIMATE Rising Sea Level
According to the EPA, global sea levels have risen by four to eight inches over the last century. The increase is attributed to melting mountain glaciers, expansion of ocean water in response to rising temperatures, melting of the polar ice sheets, and surface discharge of groundwater that has been pumped out of the ground. The sea level along much of the U.S. coast is rising more rapidly than in the rest of the world. More than half the population of the United States lives within fifty miles of a coastline. A rising sea level would narrow or destroy beaches, flood wetland areas, and either submerge or force costly fortification of shoreline property. Figure 3.14 shows areas along the southeast coast that could be vulnerable to rising sea levels because they lie at low elevations. Higher water levels would increase storm damage, and many coastal cities worldwide would be flooded. Some islands, such as the Philippines, have already seen encroachment. Residents of the Maldives, islands that lie on average three feet above sea level in the Indian Ocean, are already erecting artificial defenses, such as breakwaters made of concrete, to fend off rising seas.
• Commercial (7%)
Rising sea levels threaten millions of people living on oceanic islands and in low-lying areas of Bangladesh, parts of Japan, and coastal China. Rising waters could also intrude on inland rivers, threatening fresh water supplies and increasing the salt content of groundwater as the sea encroaches on freshwater aquifers (naturally occurring underground water reservoirs).
• Residences (6%)
Fluctuating Rainfall Patterns
• Electricity generation at power plants (34%) • Transportation (27%) • Industry (19%) • Agriculture (7%)
Emissions from most sources have increased since 1995. During the late 1990s emissions from industry began to decline and continued that trend into the early 2000s. The EPA attributes the decline to a shift in the overall U.S. economy from a focus on manufacturing industries to service-based businesses. Agricultural emissions are predominantly nitrogen-based, rather than carbon-based. Residential emissions are mainly due to CO2 The Environment
Warmer temperatures may increase the evaporation rate, thereby increasing atmospheric water vapor and cloud cover, which in turn may affect regional rainfall patterns. Some areas might receive far more rain, while others receive far less than normal. Most experts believe Africa will be the most vulnerable to climate change because its economy depends largely on rain-fed agriculture, and many farmers are too poor and ill equipped to The Enhanced Greenhouse Effect and Climate Change
51
FIGURE 3.14
Areas of the Gulf Coast lying at low elevations that are vulnerable to sea level rise
Below 1.5 meters
1.5–3.5 meters
Above 3.5 meters
100 miles
SOURCE: James G. Titus and Charlie Richman, “Gulf Coast and Florida,” in Maps of Lands Vulnerable to Sea Level Rise—on the Gulf Coast, U.S. Environmental Protection Agency, Washington, DC, 2001
adapt. Australia and Latin America could also be subject to severe drought. The Effect of Increased Temperatures on Humans
Extra heat alone would be enough to kill some people. Some deaths would occur directly from heat-induced strokes and heart attacks. Air quality also deteriorates as temperatures rise. Hot, stagnant air contributes to the formation of atmospheric ozone, the main component of smog, which damages human lungs. Poor air quality can also aggravate asthma and other respiratory diseases. Increasing ultraviolet rays can increase the incidence of skin cancers, diminish the function of the human immune system, and cause eye problems such as cataracts. Higher temperatures and added rainfall could create ideal conditions for the spread of a host of infectious diseases by insects, including mosquito-borne malaria, dengue fever, and encephalitis. Decreasing Biological Diversity
Biological diversity is also predicted to suffer from global warming. Loss of forests, tundra (arctic plains), and wetlands could irrevocably damage ecosystems. Some species that live in precise, narrow bands of temperature and humidity may find their habitats wiped out altogether. Rising seas could cover coastal mangrove swamps, causing the loss of many species, including the Bengal tiger. Plants and animals of the far north, like the polar bear and the walrus, could die out for lack of an acceptably cold environment. Many species cannot migrate rapidly enough to cope with climate change at the projected rate. 52
The Enhanced Greenhouse Effect and Climate Change
Some Possible Positive Effects
There are several possible positive consequences of global warming. Agriculture in colder climates could benefit. Milder winters could reduce the number of coldweather deaths, as well as the cost of snow clearance and heating. Northern waters could remain open longer for navigation, and the Arctic Ocean might become ice-free, opening a new trade route between Europe and Asia. COMPUTER MODELS Computer models are widely used to predict the effects on Earth’s climate of increasing concentrations of greenhouse gases. However, different models can provide quite different estimates due to uncertainty about the many variables involved.
In January 2005 British researchers reported results from a modeling experiment conducted on more than 95,000 personal computers around the world (D. A. Steinforth et al, ‘‘Uncertainty in Predictions of the Climate Response to Rising Levels of Greenhouse Gases,’’ Nature, London: Nature Publishing Group, January 27, 2005). The project climateprediction.net allows people to download climate model software onto their personal computers. The software runs in the background when the computers are not busy with other tasks. The study found that models predicted global temperature increases ranging from approximately 2 degrees Celsius to 11 degrees Celsius (3.6–19.8 degrees Fahrenheit) if atmospheric levels of carbon dioxide doubled. The Environment
FIGURE 3.15
FIGURE 3.16
Public opinion on level of understanding of the greenhouse effect, March 2005
Public opinion on whether the U.S. should abide by the Kyoto agreement on global warming, April 2005
“NEXT, THINKING ABOUT THE ISSUE OF GLOBAL WARMING, SOMETIMES CALLED THE ‘GREENHOUSE EFFECT,’ HOW WELL DO YOU FEEL YOU UNDERSTAND THIS ISSUE—WOULD YOU SAY VERY WELL, FAIRLY WELL, NOT VERY WELL, OR NOT AT ALL?”
“BASED ON WHAT YOU HAVE HEARD OR READ, DO YOU THINK THE UNITED STATES SHOULD, OR SHOULD NOT, AGREE TO ABIDE BY THE PROVISIONS OF THE KYOTO AGREEMENT ON GLOBAL WARMING?”
Not at all 6%
Very well 16%
No opinion 35%
Not very well 24%
Fairly well 54%
Adapted from “Next, thinking about the issue of global warming, sometimes called the ‘greenhouse effect,’ how well do you feel you understand this issue—would you say very well, fairly well, not very well, or not at all?” in Environment, The Gallup Organization, Princeton, NJ, April 2005, http://www.gallup.com/poll/content/default .aspx?ci1615 (accessed August 4, 2005). Copyright © 2005 by The Gallup Organization. Reproduced by permission of The Gallup Organization. SOURCE:
In June 2005 researchers reported that ocean temperature measurements indicate the Earth is absorbing more solar radiation than it reflects back to space (James Hansen et al, ‘‘Earth’s Energy Imbalance: Confirmation and Implications,’’ Science, Washington DC: American Association for the Advancement of Science, June 3, 2005). Computer modeling predicted that the Earth’s temperature will increase by approximately 1 degree Fahrenheit over the next century even if greenhouse gas concentrations remain constant at existing levels. PUBLIC OPINION ABOUT GLOBAL WARMING In March 2005 the Gallup Organization conducted its annual poll on topics related to the environment. Participants were asked several questions about global warming and the Kyoto Protocol.
Only 16% of those asked thought they understood very well the ‘‘greenhouse effect’’ issue. (See Figure 3.15). Nearly a quarter (24%) admitted they did not understand it very well. Just over half (54%) said they understood the issue fairly well. Another 6% said they did not understand the issue at all. A slim majority (54%) of those asked believe that global warming has already begun, while 15% feel that global warming will occur within the next few years or The Environment
Yes 42%
No 23%
SOURCE: Adapted from “Based on what you have heard or read, do you think the United States should, or should not, agree to abide by the provisions of the Kyoto agreement on global warming?” in Environment, The Gallup Organization, Princeton, NJ, April 2005, http://www.gallup.com/poll/content/default.aspx?ci1615 (accessed August 4, 2005). Copyright © 2005 The Gallup Organization. Reproduced by permission of The Gallup Organization.
within their lifetimes. Another 19% consider global warming a problem for the distant future, and 9% believe that it will never happen at all. This breakdown of opinions on the subject has remained fairly constant through the years. Opinion is split very evenly on whether the seriousness of global warming has been exaggerated or not. Gallup found that 35% of those responding felt that the seriousness had been generally underestimated. Another 29% thought it was generally correct, and 31% felt that the seriousness was generally exaggerated. In a poll conducted by Gallup in March 2004, 26% of respondents expressed a great deal of concern about global warming and 25% expressed a fair amount of concern. Together these opinions represent just over half of all the people polled. In 1989 nearly two-thirds of those asked felt a great deal or fair amount of concern about this issue. In 2000 nearly three-quarters did. Overall concern appears to be on a downward trend. Despite the Bush administration’s well-publicized opposition to the Kyoto treaty, Gallup’s 2005 poll shows that more people support the treaty than oppose it. Figure 3.16 illustrates that 42% of poll respondents indicated that the United States should agree to abide by the provisions of the treaty, compared with 23% who disagreed. A sizable percentage of those asked (35%) had no opinion on the matter. The Enhanced Greenhouse Effect and Climate Change
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CHAPTER 4
A HOLE IN THE SKY: OZONE DEPLETION
EARTH’S PROTECTIVE OZONE LAYER Ozone is a gas naturally present in Earth’s atmosphere. Unlike regular oxygen, which contains two oxygen atoms (O2), ozone contains three oxygen atoms (O3). A molecule of regular oxygen can be converted to ozone by ultraviolet (UV) radiation, electrical discharge (such as from lightning), or complex chemical reactions. These processes split apart the two oxygen atoms, which are then free to bind with other loose oxygen atoms to form ozone.
Ozone exists in Earth’s atmosphere at two levels— the troposphere and the stratosphere. (See Figure 4.1.) Tropospheric (or ground-level) ozone accounts for only a small portion of Earth’s total ozone, but it is a potent air pollutant with serious health consequences. Ground-level ozone is the primary component in smog and is formed via complex chemical reactions involving emissions of industrial chemicals and through fossil fuel combustion. Ozone formation is intensified during hot weather, when more radiation reaches the ground. Smog retards crop and tree growth, impairs health, and limits visibility. Approximately 90% of the Earth’s ozone lies in the stratosphere at altitudes greater than about twenty miles. (See Figure 4.2.) Ozone molecules at this level protect life on Earth by absorbing UV radiation from the sun and preventing it from reaching the ground. The so-called ozone layer is actually a scattering of molecules constantly undergoing change from oxygen to ozone and back. Although most of the ozone changes back to oxygen, a small amount of ozone persists. As long as this natural process stays in balance, the overall ozone layer remains thick enough to protect the Earth from harmful UV radiation from the sun. The amount of ozone in the stratosphere varies greatly depending upon location, altitude, and temperature. EVIDENCE OF OZONE DEPLETION Many scientists believe that the introduction of certain chemicals into the stratosphere alters the natural The Environment
ozone balance by depleting ozone molecules. Chlorine and bromine atoms are particularly destructive. They can bind to loose oxygen atoms and prevent them from reforming either oxygen or ozone. Chlorine and bromine are found in the sea salt from ocean spray. Chlorine is also present in the form of hydrochloric acid emitted with volcanic gases. These are natural sources of ozonedepleting chemicals. In the mid-1970s scientists first began to speculate that the ozone layer was rapidly being destroyed by reactions involving industrial chemicals that contained chlorine and bromine. Two chemists, F. Sherwood Rowland and Mario Molina, discovered that chlorofluorocarbons (CFCs) could break down in the stratosphere, releasing chlorine atoms that could destroy thousands of ozone molecules. This discovery led to a ban on CFCs as a propellant in aerosols in the United States and other countries. In 1984 British scientists at Halley Bay in Antarctica measured the ozone in the air column above them and discovered alarmingly low concentrations. Measurements indicated ozone levels about 50% lower than they had been in the 1960s. Scientists report ozone concentrations in units called Dobson units. The unit is named after G. M. B. Dobson (1889–1976), a British scientist who invented an instrument for measuring ozone concentrations from the ground. One Dobson unit (DU) corresponds to a layer of atmospheric ozone that would be 0.001 millimeters thick if it was compressed into a layer at standard temperature and pressure at the Earth’s surface. Atmospheric ozone is considered ‘‘thin’’ if its concentration falls below 220 DU. A thin spot in the ozone layer is commonly called an ‘‘ozone hole.’’ The extreme cold and unique climate conditions over the poles are thought to make the ozone layers there 55
FIGURE 4.1
FIGURE 4.3
Ozone in Earth’s atmosphere
Trends in size of ozone hole over Antarctica, 1994–2004 [Million square kilometer] Stratosphere: In this region, ozone is “good.” It protects us from the sun’s harmful ultraviolet radiation.
Troposphere: In this region, ozone is “bad.” It can damage lung tissue and plants.
Mesosphere
SOURCE: Adapted from Ozone: What It Is and Why Do We Care about It? NASA Facts, National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, MD, May 1998
Ozone hole area
Earth
2004
94–03 Mean
30 27 24 21 18 15 12 9 6 3 0 August
September
October
November
December
Adapted from “2004 Southern Hemisphere Ozone Hole Area,” in Stratosphere Home: Monitoring and Data: Ozone Hole Weekly Update, National Oceanic and Atmospheric Administration, National Weather Service, National Centers for Environmental Prediction, Climate Prediction Center, Camp Springs, MD, November 29, 2004, http://www.cpc.ncep.noaa.gov/products/stratosphere/sbuv2to/gif_files/ ozone_hole_plot.png (accessed August 4, 2005) SOURCE:
FIGURE 4.2
Altitude profile and distribution of ozone
• Contains 90% of atmospheric ozone • Beneficial role acts as primary UV radiation shield • Current issues:
35
Altitude (kilometers)
30
– Long-term global downward trends
Stratospheric ozone (the ozone layer)
25
– Springtime Antarctic ozone hole each year
20
– Springtime Arctic ozone losses in several recent years
15 10 “Smog” ozone 5
Tropospheric ozone
• Contains 10% of atmospheric ozone • Harmful impact: toxic effects on humans and vegetation • Current issues: – Episode of high surface ozone in urban and rural areas
0
5 10 15 20 25
Ozone amount (pressure, milli-Pascals) SOURCE: “Figure 14. Temperature Profile and Distribution of Ozone,” in Reporting and Climate Change: Understanding the Science, National Safety Council, Environmental Health Center, Washington, DC, June 2000
particularly susceptible to thinning. Where cloud and ice particles are present, reactions that hasten ozone destruction also occur on the surface of ice particles. Since 1982 an ozone hole has appeared each year over Antarctica (the South Pole) beginning in August and lasting until November. The hole formation is linked to polar clouds that form during the dark Antarctic winter (May through 56
A Hole in the Sky: Ozone Depletion
September). These clouds provide reaction surfaces for chlorine-containing compounds to release their chlorine. As sunlight returns in August or September the released chlorine begins destroying ozone molecules. The Antarctic ozone hole increased in size throughout the 1980s. By the early 1990s it was consistently larger than the area of Antarctica. Throughout most of the early 2000s the hole has been larger in size than the continent of North America. In 2002 the size of the hole dropped dramatically due to unusually warm weather at the South Pole. The hole rebounded to its largest area yet in the autumn of 2003. As shown in Figure 4.3 the 2004 hole was smaller than the mean of the holes experienced from 1994 to 2003. Ozone depletion has also been detected over other parts of the world. In 1993 satellite measurements indicated a 10–20% reduction in ozone levels over parts of Canada, Scandinavia, Russia, and Europe compared to 1992 levels. In January 2002 the European Space Agency (ESA) announced that ozone thinning had been detected over Europe by the Global Ozone Monitoring Experiment instrument aboard the ESA’s ERS-2 satellite. The thinning in the ozone layer lasted for only three days. Similar thinning was observed previously in November 1999 and November 2001. Scientists believe that unusual air currents in the stratosphere, rather than chemical depletion, may be responsible for the thinning. The Environment
In 1995 scientists first detected thinning of the ozone over the Arctic (the North Pole). Historically Arctic winters have been warmer than those in Antarctica. This helped protect the northern pole from ozone depletion. However, during the 1990s and early 2000s scientists reported increasingly colder temperatures over the Arctic region and formation of more polar clouds. In April 2005 European researchers reported the lowest Arctic levels of ozone since monitoring began decades ago. CONSEQUENCES OF OZONE DEPLETION Ironically, destruction of the ozone layer at the upper levels could increase the amount of ozone at the Earth’s surface. In addition, the decline in stratospheric ozone is thought to increase hydrogen peroxide in the stratosphere, contributing to acid rain. The ozone layer acts as a protective shield against UV radiation. As ozone diminishes in the upper atmosphere, the Earth could receive more UV radiation. Increased radiation, especially of the frequency known as ultraviolet-B (UVB), the most damaging wavelength, promotes skin cancers and cataracts, suppresses the human immune system, and produces wrinkled, leather-like skin. It also reduces crop yields and fish populations, damages some materials such as plastics, and intensifies smog creation.
At its Web site in 2005 the EPA reported that studies conducted at the Antarctic found that the amount of UVB radiation reaching the ground doubled during the existence of the Antartic’s annual ozone hole. Threats to Human Health The most obvious threat of ozone depletion to humans is increased exposure to UVB radiation that causes skin cancer and cataracts. There are two types of skin cancer: nonmelanoma and melanoma.
The American Cancer Society reported in 2005 that more than one million cases of nonmelanoma skin cancer are diagnosed in the United States each year and estimated that between one thousand and two thousand people would die from the disease. The incidence of cancer is closely tied to cumulative exposure to UV radiation. In 1988 the EPA estimated that each 1% drop in ozone is projected to result in a 4–6% increase in these types of skin cancer. Melanoma skin cancer is less common, but far more deadly, accounting for just 4% of skin cancer cases but a staggering 79% of skin cancer deaths, according to the American Cancer Society in 2005. Melanoma is more likely to metastasize (spread to other parts of the body, particularly major organs such as the lungs, liver, and brain). In April 2005 the American Cancer Society predicted that in 2005 there would be 59,600 new cases of melanoma in the United States and that 7,800 Americans The Environment
would die from the disease. Melanoma appears to be associated with acute radiation exposure, such as severe sunburns, which are more likely to occur when the ozone hole is larger. Increased radiation exposure is also blamed for cataracts. This is a clouding of the eye’s lens that causes blurred vision and—if left untreated—blindness. Some medical researchers theorize that UV radiation also depresses the human immune system, lowering the body’s resistance to tumors and infectious diseases. Damage to Plant and Animal Ecosystems Terrestrial and aquatic ecosystems are also affected by the depletion of the ozone layer. UV radiation alters photosynthesis, plant yield, and growth in plant species. Phytoplankton (one-celled organisms found in the ocean) are the backbone of the marine food web. According to the EPA, excessive exposure to UVB radiation reduces the productivity and survival rate for these organisms. Diminishing phytoplankton supplies would likely harm many fish species that depend on them for food.
Studies performed in the mid-1990s blamed the rise in UV radiation caused by the thinning of the ozone layer for the decline in the number of frogs and other amphibians. Deterioration of Materials Increased UV radiation also affects synthetic materials. Plastics are especially vulnerable, tending to weaken, become brittle and discolored, and break. OZONE-DEPLETING CHEMICALS Most ozone destruction in the atmosphere is believed to be anthropogenic (caused by humans). In 1999 the World Meteorological Organization in Geneva, Switzerland, estimated that only 18% of the sources contributing to ozone depletion were natural. The remaining 82% of sources contributing to ozone depletion were industrial chemicals. The blame is largely placed on chemicals developed by modern society for use as refrigerants, air conditioning fluids, solvents, cleaning agents, and foam-blowing agents. These chemicals can persist for years in the atmosphere. Thus, there is a significant lag between the time that emissions decline at the Earth’s surface and the time at which ozone levels in the stratosphere recover.
Table 4.1 lists the chemicals of particular concern to scientists worried about thinning ozone levels. Each chemical is assigned a value called an ozone depletion potential (ODP) based on its harmfulness to the ozone layer. The most common depleters are the chlorofluorocarbons known as CFC-11, CFC-12, and CFC-13. Each of these chemicals is arbitrarily assigned an ODP of 1. The ODPs for other chemicals are determined by A Hole in the Sky: Ozone Depletion
57
TABLE 4.1
FIGURE 4.4
Lifetime and ozone depletion potential of various chemicals Lifetime in years
Destruction of ozone
Ozone depletion potential
UV
(1)
Class I
(2)
CFC-11 CFC-12 CFC-13 CFC-113 CFC-114 CFC-115 Halon 1211 Halon 1301 Halon 2402 Carbon tetrachloride Methyl bromide Methyl chloroform
45 100 640 85 300 1,700 16 65 20 26 0.7 5
1 1 1 0.8–1 0.94–1 0.44–0.6 3–6 10–12 6–8.6 0.73–1.1 0.38–0.6 0.1–0.12
F
Chlorine atom
Cl C Ozone molecule (3)
Cl Cl Chlorofluorocarbon (CFC) molecule
Chlorine monoxide (4)
Class II HCFC-21 HCFC-22 HCFC-123 HCFC-124 HCFC-141b HCFC-142b HCFC-225ca HCFC-225cb
1.7 1.2 1.3 5.8 9.3 17.9 1.9 5.8
0.04 0.05–0.055 0.02–0.06 0.02–0.04 0.1–0.12 0.06–0.07 0.02–0.025 0.03–0.033
The ODP is the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of CFC-11. Thus, the ODP of CFC-11 is defined to be 1.0. Other CFCs and HCFCs have ODPs that range from 0.01 to 1.0.
Adapted from “Class I Ozone-Depleting Substances” and “Class II Ozone-Depleting Substances,” in Ozone Depletion Chemicals, U.S. Environmental Protection Agency, Washington, DC, February 12, 2004, http://www.epa.gov/ozone/ods.html and http://www.epa.gov/ozone/ods2.html (accessed August 4, 2005) SOURCE:
Destruction of ozone is a catalytic process— Chlorofluorocarbon (1) atoms in the stratosphere are split by ultraviolet radiation and release their chlorine atom (2).
Oxygen molecule The chlorine atom takes one oxygen atom from the unstable molecule (3) and forms chlorine monoxide (4), leaving an ordinary oxygen molecule (5). When a free atom of oxygen (6) collides with the chlorine monoxide (7) the two oxygen atoms form a molecule (8) – releasing the chlorine atom (9) to destroy more ozone (10).
comparing their relative harmfulness to that of CFC-11. In general, Class I chemicals are those with an ODP value greater than or equal to 0.2 and Class II chemicals have ODP values less than 0.2.
Over time, new formulations were discovered and the possibilities for use seemed endless. CFCs could be used as coolants in air conditioners and refrigerators, as propellants in aerosol sprays, in certain plastics such as polystyrene, in insulation, in fire extinguishers, and as cleaning agents. World production doubled every five years through 1970, and another growth spurt occurred in the 1980s as new uses were discovered—primarily as a solvent to clean circuit boards and computer chips. 58
A Hole in the Sky: Ozone Depletion
(6) (7)
(8) (9)
Ozone molecule (10)
Class I Chemicals
Although a number of chemicals can destroy stratospheric ozone, CFCs are the main offenders because they are so prevalent. When CFCs were invented in 1930, they were welcomed as chemical wonders. Discovered by Thomas Midgley, Jr., they were everything the refrigeration industry needed at the time—nontoxic, nonflammable, noncorrosive, stable, and inexpensive. Their artificial cooling provided refrigeration for food and brought comfort to warm climates. The compound was originally marketed under the trademark Freon.
(5)
Adapted from Ozone: What It Is and Why Do We Care about It? NASA Facts, National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, MD, May 1998 SOURCE:
CFCs are extremely stable; it is this stability that allows them to float intact through the troposphere (the layer of air nearest the Earth’s surface) and into the ozone layer. It can take up to six to eight years for them to reach the stratosphere. Once there, some can survive for hundreds of years. CFCs do not degrade in the lower atmosphere but, on entering the stratosphere, they encounter the sun’s UV radiation and eventually break down into chlorine, fluorine, and carbon. Many scientists believe it is the chlorine that damages the ozone layer. (See Figure 4.4.) While CFCs are primarily blamed for ozone loss, other gases are also at fault. One of those gases is halon, The Environment
which contains bromine. As shown in Table 4.1, halons have much higher ODP values than do CFCs. The bromine atoms in halons destroy ozone in a manner similar to that shown in Figure 4.4 for chlorine, but they are chemically more powerful. This means that the impact to ozone of a particular mass of halon is more destructive than a similar mass of a CFC. Halons are relatively long-lived in the atmosphere, lingering for up to sixty-five years before being broken down. Halon is used primarily for fighting fires. Civilian and military fire-fighting training accounts for much of the halon emission. Other Class I ozone destroyers include carbon tetrachloride, methyl bromide, and methyl chloroform. These chemicals are commonly used as solvents and cleaning agents. Class II Chemicals The most common Class II ozone-depleting chemicals are hydrochlorofluorocarbons (HCFCs). HCFCs contain hydrogen. This makes them more susceptible to atmospheric breakdown than CFCs. As shown in Table 4.1, most HCFCs have a lifetime of less than six years. The most long-lived, HCFC-142b, lasts for only 17.9 years. HCFCs have much lower ODP values than CFCs, halons, and industrial ozone depleters. HCFCs are considered good short-term replacements for CFCs. Although HCFCs are less destructive to ozone than the chemicals they are replacing, scientists believe that HCFC use must also be phased out to allow the ozone layer to fully recover. A LANDMARK IN INTERNATIONAL DIPLOMACY: THE MONTREAL PROTOCOL CFCs and halons were widely used in thousands of products and represented a significant share of the international chemical industry, with billions of dollars in investment and hundreds of thousands of jobs. Ozone depletion was a global problem that necessitated international cooperation, but nations mistrusted one another’s motives. As with the issues of global warming and pollution, developing countries resented being asked to sacrifice their economic development for a problem they felt the industrialized nations had created. To complicate matters, gaps in scientific proof led to disagreements over whether a problem actually existed.
In 1985, as the first international response to the ozone threat, twenty nations signed an agreement in Vienna, Austria, calling for data gathering, cooperation, and a political commitment to take action at a later date. In a 1987 negotiators meeting in Montreal, Canada, the participants finalized a landmark in international environmental diplomacy: the Montreal Protocol on Substances That Deplete the Ozone Layer. It is generally The Environment
TABLE 4.2
Phase-out schedule under the Montreal Protocol for ozonedepleting substances
Ozone-depleting substance Halons Carbon tetrachloride Chlorofluorocarbons (CFCs) Hydrobromofluorocarbons (HBFCs) Methyl chloroform Bromochloromethane Methyl bromide Hydrochlorofluorocarbons (HCFCs) SOURCE:
Developed countries must phase out by:
Developing countries must phase out by:
1994 1996 1996 1996 1996 1999 2005 2030
2010 2010 2010 1996 2015 1999 2015 2040
Created by Kim Masters Evans for Thomson Gale, 2005
referred to as the Montreal Protocol. The agreement was signed by twenty-nine countries including the United States, Canada, Mexico, Japan, Australia, all western European nations, the Russian Federation, and a handful of other countries around the world. The agreement called for industrial countries to cut CFC emissions in half by 1998 and to reduce halon emissions to 1986 levels by 1992. Developing countries were granted deferrals to compensate for their low levels of production. Industrial countries agreed to reimburse developing countries that complied with the protocol for ‘‘all agreed incremental costs,’’ meaning all additional costs above any they would have expected to incur had they developed their infrastructure in the absence of the accord. And, very importantly, the protocol also called for further amending as new data became available. Throughout the 1990s and early 2000s new scientific information revealed that ozone depletion was occurring faster than expected. This news spurred calls to revise the treaty. In total, four amendments to the Montreal Protocol have been adopted. These are known as the London Amendment (effective 1992), the Copenhagen Amendment (effective 1994), the Montreal Amendment (effective 1999), and the Beijing Amendment (effective 2002). The final phaseout schedule for ozone-depleting substances is shown in Table 4.2. The Montreal Protocol has been hailed as an historic event—the most ambitious attempt ever to combat environmental degradation on a global scale. It ushered in a new era of environmental diplomacy. Some historians view the signing of the accord as a defining moment, the point at which the definition of international security was expanded to include environmental issues as well as military matters. In addition, an important precedent was established—that science and policymakers had a new relationship. Many observers thought that the decision to take precautionary action in the absence of complete A Hole in the Sky: Ozone Depletion
59
proof of a link between CFCs and ozone depletion was an act of foresight that would now be possible with other issues. MONTREAL PROTOCOL PROBLEMS Implementation and enforcement of the Montreal Protocol have been aggravated by numerous factors. In August 2003 the United Nations Environment Programme (UNEP) summarized these problems in ‘‘Backgrounder: Basic Facts and Data on the Science and Politics of Ozone Protection’’ (http://www.unep.ch/ ozone/pdf/Press-Backgrounder.pdf ). The report listed five major challenges facing complete implementation of the Montreal Protocol:
• Incomplete ratification of all amendments • Economic difficulties in the Russian Federation and other countries • Increasing illegal trade and smuggling of banned substances • Increasing CFC consumption in developing countries, particularly Asia Amendment Ratification Moves Slowly The United Nations reported that 189 countries had ratified the original Montreal Protocol as of March 2005. Nations have been slow to ratify the amendments. For example, as of early 2005 only ninety-one nations have ratified the Beijing Amendment. The United States has ratified all amendments to the Montreal Protocol. Economic Problems Hinder Progress The 2003 UNEP report noted that the Russian Federation and a few other countries were having difficulties meeting the phase-out schedule in the Montreal Protocol due to financial problems. The United Nations Development Program and the World Bank have secured more than $179 million in funds given by developed nations to help struggling countries phase out CFC production. An additional $60 million has been pledged to assist them in phasing out other ozonedepleting substances. Illegal Trade and Smuggling of CFCs In 1996 the ban on CFCs was implemented in the developed countries, including the United States. The CFC called Freon was widely used in automobile air conditioners prior to that time. After the ban went into effect there were still millions of Americans with cars that used Freon as a refrigerant. Although alternative refrigerants were available, they were more expensive than Freon. The result was a black market for the product.
Several U.S. government agencies—the EPA, the Customs Service, the Departments of Commerce and 60
A Hole in the Sky: Ozone Depletion
Justice, and the Internal Revenue Service—began intensive antismuggling efforts. In 2000 the EPA reported that approximately two million pounds of CFCs and other ozone-depleting substances had been seized and impounded since the 1996 phaseout of CFCs began, and more than ninety individuals and businesses had been charged with smuggling. Early arrests for CFC smuggling were made primarily in Miami; authorities then began to notice these illegal imports creeping into other port cities, such as Houston and Baltimore. They also made their way into Europe, which banned CFCs one year before the United States. In late 2003 a London-based nonprofit organization called the Environmental Investigation Agency (EIA) reported that international trade in illegal ozone-depleting substances was very detrimental to achieving progress under the Montreal Protocol (Tom Maliti, ‘‘Illegal Trade in Ozone-Depleting Substances Is Thriving over Three Continents, Says Report,’’ Associated Press, November 11, 2003). The report noted that demand for illegal CFCs remained high in the United States, Russia, China, Vietnam, Cambodia, and Nepal. Successful smuggling of CFCs typically involves false labeling, counterfeit paperwork, and fake export corporations. The EIA estimated worldwide trade in illegal CFCs to be eighteen to twenty-seven million kilograms per year. During the early 2000s U.S. law enforcement officials broke up a massive Freon smuggling ring based in Panama that operated during the 1990s to supply Freon to customers in southern Florida. Two of the men involved were sentenced to up to two years in prison for their role in the smuggling scheme and for tax evasion. The ring leader was found guilty of tax fraud and money laundering. In May 2004 he was sentenced to seventeen years in prison and ordered to pay a $20 million fine. He also had to restitute the Internal Revenue Service $6.6 million for tax evasion. Demand Increasing for CFCs in Developing Countries
The developing countries must phase out CFC consumption by 2010. The 2003 UNEP report notes that demand for CFCs is actually increasing, not decreasing, in many of these countries. This is particularly true in Asia and Latin America where a growing middle class has increased demand for consumer products that use refrigerants. Much of this demand is met by imported goods. The UNEP complains that developed countries are exporting ‘‘a large number’’ of used and older model refrigeration units that use CFCs instead of acceptable alternatives. This will make it much more difficult for the developing countries to reduce their demand for CFCs by the phase-out deadline. The Environment
FIGURE 4.5
Trends in atmospheric concentrations of controlled ozone-depleting chemicals, 1987–2001
BRW
NWR
CFC-11
MLO
SMO
SPO
CFC-12
285
560
280
540
275 520 270 500 ppt
ppt
265 260 255
480 460
250
440
245 420
240 235 1985
1990
1995
400 1985
2000
CH3CCI3
1990
1995
2000
1990
1995
2000
CCI4 110
160 105 140 100
120
ppt
ppt
100
95
60 90 40 85
20 0 1985
1990
1995
2000
80 1985
SOURCE: “Trends of Controlled Ozone Depleting Chemicals,” in Halocarbons and Other Atmospheric Trace Species Group: Figures, U.S. Department of Commerce, National Oceanic and Atmospheric Administration, Climate Monitoring and Diagnostics Laboratory, Boulder, CO, 2002, http://www.cmdl .noaa.gov/hats/graphs/graphs.html (accessed August 4, 2004)
MONITORING DATA SHOW PROGRESS The National Oceanic and Atmospheric Administration (NOAA) is an agency of the U.S. Department of Commerce. NOAA operates the Climate Monitoring and Diagnostics Laboratory (CMDL) headquartered in Boulder, Colorado. The CMDL collects data at its observatories around the world and does research related to global trends in air quality.
Figure 4.5 shows atmospheric data for four ozonedepleting chemicals: CFC-11, CFC-12, methyl chloroform (CH3CCl3), and carbon tetrachloride (CCl4). The The Environment
data were collected at five CMDL observatories as follows: • Point Barrow, Alaska (BRW) • Niwot Ridge, Colorado (NWR) • Mauna Loa, Hawaii (MLO) • Cape Matatula, American Samoa (SMO) • South Pole, Antarctica (SPO) After peaking in the early 1990s the atmospheric concentrations of CFC-11 began to decline. Concentrations A Hole in the Sky: Ozone Depletion
61
of methyl chloroform and carbon tetrachloride have declined dramatically since 1990. CFC-12 concentrations were beginning to level off in 2002 after climbing steadily for decades. CFC-12 has the longest atmospheric lifetime (one hundred years) of the four compounds.
• Ozone depletion has been recorded at certain times over the North Pole during the last decade. However, scientists do not believe that an Arctic ozone hole that returns on a regular basis is likely to form due to the highly variable meteorological conditions at the North Pole.
THE LATEST SCIENTIFIC ASSESSMENT Article 6 of the Montreal Protocol requires that the ratifying nations base their decision making on scientific information assessed and presented by an international panel of ozone experts. This panel includes the World Meteorological Organization (WMO), UNEP, the European Commission, and two U.S. organizations—NOAA and the National Aeronautics and Space Administration (NASA).
• Measurements taken at various sites around the world indicate an increase of 6–14% in the amount of ultraviolet radiation reaching the ground since the early 1980s. However, lack of long-term data and an abundance of other factors besides ozone that affect UV levels (such as cloudiness) make it difficult to determine the statistical significance of the recorded UV increases.
In March 2003 the WMO published the panel’s latest findings in Scientific Assessment of Ozone Depletion: 2002. This is the fifth scientific assessment of the world’s ozone condition. Previous assessments were published in 1989, 1991, 1994, and 1998. The reports are based on analysis of data collected from satellites, aircraft, balloons, and ground-based instruments and the results of laboratory investigations and computer modeling. The scientific assessment published in 2003 presents the following major findings: • For the period 1997–2001 Earth’s average stratospheric ozone concentration was approximately 3% less than the concentration measured prior to 1980 (the baseline condition). • Ozone loss has occurred primarily at Earth’s poles and over mid-latitude regions of the Northern and Southern hemispheres. No statistically significant ozone loss has been recorded over tropical regions near Earth’s equator. • Ozone depletion over the Southern hemisphere occurs year-round. Depletion over the Northern hemisphere is more seasonal, worsening during winter and spring months. Ozone depletion over Antarctica (the ‘‘ozone hole’’) has historically been a springtime phenomenon. However, data collected in recent years show that the ozone hole is persisting for a longer time each year, not disappearing until early summer. • Ozone concentrations measured over Antarctica during occurrences of the ozone hole consistently average 40–50% less than concentrations measured prior to 1980. • The average size of the Antarctic ozone hole increased during the 1980s and 1990s. Although the growth rate was slower during the 1990s than it was during the 1980s, scientists are not sure yet that the size of the hole has reached a maximum. 62
A Hole in the Sky: Ozone Depletion
• The total concentration of ozone-depleting chemicals in the troposphere (lower atmosphere) has declined since peaking in 1992–94. Chlorine concentrations measured in 2000 were 5% lower than those recorded in 1992–94. Bromine concentrations increased by 3% per year over the same time period. The increase in bromine is blamed on halon emissions. Atmospheric concentrations of methyl chloroform have declined significantly. CFC-11 and CFC-113 concentrations are also decreasing. CFC-12 concentrations continue to increase, although at a slower rate each year than in previous decades. • Continued reductions in ozone-depleting chemicals in the stratosphere should lead to complete recovery of Earth’s ozone layer during the twenty-first century. Computer models suggest that falling atmospheric ozone concentrations should level off by the year 2012 and then begin to increase to their normal levels. The annual occurrence of the Antarctic ozone hole is expected to cease by the year 2050. UNITED STATES EFFORTS TO END OZONE DEPLETION In the industrial world many countries did more than was required by the protocol. As a result, when the official CFC phase-out date arrived, most industrial nations were ready, and some had phased out ozonedepleting substances before the deadlines. By the end of 1994 the European Union no longer permitted CFCs.
Title VI of the 1990 Clean Air Act Amendments (PL 101–549) is the United States’s primary response to ozone depletion. As part of the act, the U.S. Congress approved a provision requiring the president to speed up the schedule for chemical phase out if new evidence warranted it. In fact, new data did become available, including worrisome evidence that showed ozone depletion was occurring over the Northern Hemisphere. In addition to banning Freon in 1997, the Clean Air Act required the United States to end the use of methyl bromide by 2001—nine years ahead of protocol requirements. The Environment
alleged violations at a Tennessee manufacturing facility. In 2004 the Wal-Mart Corporation was fined $400,000 for selling Freon to customers who were not properly certified under EPA regulations.
TABLE 4.3
U.S. emissions of ozone-depleting substances, 1990, 1995, 2000–2003 Compound
1990
1995
2000
2001
2002
2003
28.0
9.7
10.2
9.7
9.2
8.8
Class I CFC-11
SOURCE: Adapted from “Table 6-9. Emissions of Ozone Depleting Substances (Gg),” in Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2003, U.S. Environmental Protection Agency, Washington, DC, April 15, 2005, http://yosemite.epa.gov/oar/globalwarming.nsf/UniqueKey Lookup/RAMR69VR UT/$File/05_annex_Chapter6.pdf (accessed August 4, 2005)
U.S. emissions of ozone-depleting substances for various years between 1990 and 2003 are shown in Table 4.3. Emissions of all Class I substances have decreased since 1990. Although these compounds are no longer produced in the United States, the EPA reports that large amounts remain in existing equipment, and stockpiles are used to maintain the equipment. Therefore, emissions of these compounds are expected to continue for many years but are also expected to continue declining over time. Emissions of Class II substances have all increased since 1990. U.S. production of these compounds for domestic use is scheduled to end by the year 2030. In April 2005 the U.S. Food and Drug Administration (FDA) adopted a final rule banning the use of such ozone-depleting substances as propellants in medical inhalers. This use was exempted from the general ban on CFCs that went into effect during the 1990s. The FDA rule prohibits distribution of metered-dose inhalers using CFCs after December 31, 2008. The agency reports that alternative acceptable propellants for the devices are available on the market and should adequately serve patient needs. Although CFCs are no longer used in new applications in the United States, existing users can continue using them provided they are maintained under strict regulation, such as being replenished and ‘‘reclaimed’’ by authorized technicians. The EPA Office of Enforcement and Compliance Assurance can levy civil fines and criminal prosecutions against companies and individuals who violate regulations regarding ozone-depleting substances. During the early 2000s civil actions were taken against dozens of corporations and even a university for violating regulations regarding refrigerant leak repairs. In 2003 Earthgrains Baking Companies paid a $5.25 million civil penalty for corporate-wide violations. In May 2005 the DuPont Corporation was penalized $2.5 million for The Environment
Recycled halon and inventories produced before January 1, 1994, are the only supplies now available. It is legal under the Montreal Protocol and the U.S. Clean Air Act to import recycled halon, but each shipment requires approval from the EPA. Certain uses, such as fire protection, are classified as ‘‘critical use’’ and are permitted as long as supplies remain. The EPA also maintains a list of acceptable substitutes for halon. SUBSTITUTES AND NEW TECHNOLOGIES As pressure increased to discontinue use of CFCs and halons, substitute chemicals and technologies began to be developed. One of the most popular substitutes is a class of compounds called hydrofluorocarbons (HFCs). HFCs do not contain chlorine, a potent ozone destroyer. They are also relatively short-lived in the atmosphere. Most survive intact for less than twelve years. This means that HFCs do not directly impact Earth’s protective ozone layer. HFCs have ODP values of zero.
During the 1990s use of HFCs increased dramatically. NASA reports that atmospheric levels of HFCs also surged over this time period. This is a concern to scientists studying global warming because HFCs are believed to enhance atmospheric heating. Also, HFC breakdown in the atmosphere produces a chemical called trifluoroacetic acid, large concentrations of which are known to be harmful to certain plants (particularly in wetlands). Continued heavy use of HFCs during the twenty-first century could introduce or aggravate other environmental problems. Development of effective chemical substitutes with acceptable health and environmental effects is an enormous challenge. Some experts propose returning to the refrigerant gases used before the invention of CFCs. These include sulfur dioxide, ammonia, and various hydrocarbon compounds. However, these chemicals have their own issues; for example, most are highly toxic. The EPA’s Significant New Alternative Policy program evaluates alternatives to ozone-depleting substances and determines their acceptability for use. Submissions for evaluation include those that could be used in a variety of industrial applications, including refrigeration and air conditioning, foam blowing, and fire suppression and protection. Many industrial engineers are pursuing new technologies for cooling, including semiconductors that cool down when charged with electricity, refrigeration that uses A Hole in the Sky: Ozone Depletion
63
plain water as a refrigerant, and the use of thermoacoustics (sound energy). Extensive investment in research and development of new technologies will be required to produce cooling methods acceptable to industry and environmentalists. PUBLIC OPINION ABOUT THE OZONE In March 2004 the Gallup Organization conducted its annual poll of Americans’ beliefs and attitudes about environmental issues. The results show that damage to the Earth’s ozone layer ranks very low on the list of environmental problems about which Americans are worried. (See Figure 1.10 in Chapter 1.) Only 33% of those asked in 2004 expressed a great deal of worry about damage to the ozone layer. As shown in Table 4.4, this percentage is down from a peak of 51% in 1989. In 2004 another 27% expressed a fair amount of concern about the problem, while 26% felt only a little concern and 14% felt no concern at all.
64
A Hole in the Sky: Ozone Depletion
TABLE 4.4
Public concern about damage to the Earth’s ozone layer, 1989–2004 “PLEASE TELL ME IF YOU PERSONALLY WORRY ABOUT THIS PROBLEM A GREAT DEAL, A FAIR AMOUNT, ONLY A LITTLE, OR NOT AT ALL. DAMAGE TO THE EARTH’S OZONE LAYER?”
2004 Mar 8–11 2003 Mar 3–5 2002 Mar 4–7 2001 Mar 5–7 2000 Apr 3–9 1999 Apr 13–14 1997 Oct 27–28 1991 Apr 11–14 1990 Apr 5–8 1989 May 4–7
Great deal %
Fair amount %
Only a little %
Not at all %
No opinion %
33 35 38 47 49 44 33 49 43 51
27 31 29 28 29 32 27 24 28 26
26 21 21 16 14 15 25 16 15 13
14 12 11 8 7 8 13 8 10 8
* 1 1 1 1 1 2 4 4 2
SOURCE: “Please tell me if you personally worry about this problem a great deal, a fair amount, only a little, or not at all. Damage to the Earth’s ozone layer?” in Poll Topics and Trends: Environment, The Gallup Organization, Princeton, NJ, March 17, 2004, www.gallup.com (accessed August 4, 2004). Copyright © 2004 by The Gallup Organization. Reproduced by permission of The Gallup Organization.
The Environment
CHAPTER 5
ACID RAIN
WHAT IS ACID RAIN?
Acid rain is the common name for acidic deposits that fall to Earth from the atmosphere. The term was coined in 1872 by English chemist Robert Angus Smith to describe the acidic precipitation in Manchester, England. Today scientists study both wet and dry acidic deposits. Although there are natural sources of acid in the atmosphere, acid rain is primarily caused by emissions of sulfur dioxide (SO2) and nitrous oxide (N2O) from electric utilities burning fossil fuels, especially coal. These chemicals are converted to sulfuric acid and nitric acid in the atmosphere and can be carried by the winds for many miles from where the original emissions took place. (See Figure 5.1.) Wet deposition occurs when the acid falls in rain, snow, or ice. Dry deposition is caused by very tiny particles (or particulates) in combustion emissions. They may stay dry as they fall or pollute cloud water and precipitation. Moist deposition occurs when the acid is trapped in cloud or fog droplets. This is most common at high altitudes and in coastal areas. Whatever its form, acid rain can create dangerously high levels of acidic impurities in water, soil, and plants. Measuring Acid Rain
The acidity of any solution is measured on a potential hydrogen (pH) scale numbered from zero to fourteen, with a pH value of seven considered neutral. Values higher than seven are considered more alkaline or basic (the pH of baking soda is eight); values lower than seven are considered acidic (the pH of lemon juice is two). The pH scale is a logarithmic measure. This means that every pH change of one is a ten-fold change in acid content. Therefore, a decrease from pH seven to pH six is a tenfold increase in acidity; a drop from pH seven to pH five is a one hundred-fold increase in acidity; and a drop from pH seven to pH four is a one thousand-fold increase. (See Figure 5.2.) The Environment
Pure, distilled water has a neutral pH of seven. Normal rainfall has a pH value of about 5.6. It is slightly acidic because it accumulates naturally occurring sulfur oxides (SO5) and nitrogen oxides (NO5) as it passes through the atmosphere. Acid rain has a pH of less than 5.6. Figure 5.3 shows the average rainfall pH measured during 2003 at various field laboratories around the country by the National Atmospheric Deposition Program, a cooperative project between many state and federal government agencies and private entities. Rainfall was most acidic in Mid-Atlantic and Southeastern states, particularly New York, Pennsylvania, Maryland, Ohio, West Virginia, Virginia, eastern Tennessee, and Kentucky. Unfortunately, the areas with lowest rainfall pH contain some of the country’s most sensitive natural resources—the Appalachian Mountains, Adirondack Mountains, Chesapeake Bay, and Great Smoky Mountains National Park. SOURCES OF SULFATE AND NITRATE IN THE ATMOSPHERE Natural Sources Natural sources of sulfate in the atmosphere include ocean spray, volcanic emissions, and readily oxidized hydrogen sulfide released from the decomposition of organic matter found in the Earth. Natural sources of nitrogen or nitrates include NO5 produced by microorganisms in soils, by lightning during thunderstorms, and by forest fires. Scientists generally speculate that onethird of the sulfur and nitrogen emissions in the United States comes from these natural sources (this is a rough estimate as there is no way to measure natural emissions as opposed to those that are manmade). Sources Caused by Human Activity According to the Web site of the Environmental Protection Agency (EPA), the primary anthropogenic 65
FIGURE 5.1
FIGURE 5.2
Origins of acid rain
The potential hydrogen (pH) scale Mean pH of Adirondack Lakes–1975 “Pure” rain (5.6) Mean pH of Adirondack Lakes–1930s Distilled water Baking soda
Lemon juice Vinegar Particulate pollutants in atmosphere
Gaseous pollutants in atmosphere
Acid rain
Pollutants in cloud water and precipitation
Dry deposition
NOx
Dry deposition
SOURCES
VOC VOC NOx
Wet deposition
NOx SO2
SO2 Natural RECEPTORS Anthropogenic A combination of natural and manmade activities result in the deposition of acidic compounds. SOURCE: “Figure 1. Origins of Acid Rain,” in Progress Report on the EPA Acid Rain Program, U.S. Environmental Protection Agency, Washington, DC, November 1999
0
1
2
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6
7
8
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Neutral
10
11
12
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14
Basic
The pH scale The pH (“potential hydrogen”) scale is a measure of hydrogen ion concentration. Hydrogen ions have a positive electrical charge and are called cations; ions with a negative electrical charge are known as anions. A substance containing equal concentrations of cations and anions so that the electrical charges balance is neutral and has a pH of 7. However, a substance with more hydrogen ions than anions is acidic and has a pH less PH 4
PH 5
than 7; substances with more anions than cations are alkaline and have pH measures above 7. Thus, as the concentration of hydrogen ions increases, the pH decreases. But the pH scale says nothing about whether the cations or anions are from natural or manmade sources; a hydrogen ion from an industrial smokestack measures the same on the scale as a hydrogen ion from natural minerals.
PH 6
PH 7
⫽Acid content
(human-caused) contributors to acid rain are SO2 and NOx, resulting from the burning of fossil fuels, such as coal, oil, and natural gas. Fuel combustion by fossilfueled electric utilities historically has been the greatest source of these emissions, accounting for 69% of them in 2003. Fuel combustion at industrial facilities contributed another 14%. Lesser sources included transportation vehicles and industrial processes. Highway vehicles are the primary source of NOx emissions, accounting for 36% of the total in 2003. Fuel combustion in power plants is another major source, accounting for 22% of the total. Other major sources include off-highway vehicles (20%) and fuel combustion at industrial facilities (13%). NATURAL FACTORS THAT AFFECT ACID RAIN DEPOSITION Major natural factors contributing to the impact of acid rain on an area include air movement, climate, and topography and geology.
Transport systems—primarily the movement of air— distribute acid emissions in definite patterns around the planet. The movement of air masses transports emitted pollutants many miles, during which the pollutants are transformed into sulfuric and nitric acid by mixing with clouds of water. 66
Acid Rain
Remember The lower the pH value, the higher the acid content. Each full pH unit drop represents a tenfold increase in acidity. SOURCE: “The Potential Hydrogen (pH) Scale,” in Acid Rain, U.S. Environmental Protection Agency, Washington, DC, 1980
In drier climates, such as those of the western United States, windblown alkaline dust moves more freely through the air and tends to neutralize atmospheric acidity. The effects of acid rain can be greatly reduced by the presence of basic (also called alkali) substances. Sodium, potassium, and calcium are examples of basic chemicals. When a basic and an acid chemical come into contact, they react chemically and neutralize each other. On the other hand, in more humid climates where there is less dust, such as along the eastern seaboard, precipitation is more acidic. Areas most sensitive to acid rain contain hard, crystalline bedrock and very thin surface soils. When no alkaline-buffering particles are in the soil, runoff from rainfall directly affects surface waters, such as mountain streams. In contrast, a thick soil covering or soil with a high buffering capacity, such as flat land, neutralizes acid rain better. Lakes tend to be most susceptible to acid rain because of low alkaline content in lake beds. A lake’s depth, its watershed (the area draining into the lake), and the amount of time the water has been in the lake are also factors. The Environment
FIGURE 5.3
Field measurements of pH values from the National Atmospheric Deposition Program/National Trends Network, 2003
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Sites not pictured: AK01 AK03 HI99 PR20 VI01
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Note: AK is Alaska; HI is Hawaii; PR is Puerto Rico; VI is Virgin Islands.
Adapted from “Hydrogen Ion Concentration as pH from Measurements Made at the Field Laboratories, 2003,” in Hydrogen Ion Concentration as pH from Measurements Made at the Field Laboratories, 2003, National Atmospheric Deposition Program, Champaign, IL, 2005, http://nadp.sws.uiuc.edu/ isopleths/maps2003/phfield.pdf (accessed August 4, 2005) SOURCE:
EFFECTS OF ACID RAIN ON OUR ENVIRONMENT In nature the combination of rain and oxides is part of a natural balance that nourishes plants and aquatic life. However, when the balance is upset, the results to the environment can be harmful and destructive. (See Table 5.1.) Aquatic Systems
Although pH levels vary considerably from one body of water to another, a typical pH range for the lakes and rivers in the United States is six to eight. Low pH levels kill fish eggs, frog eggs, and fish food organisms. The degree of damage depends on several factors, one of which is the buffering capacity of the watershed soil—the higher the alkalinity, the more slowly the lakes and streams acidify. The exposure of fish to acidified freshwater lakes and streams has been intensely studied since the 1970s. Scientists distinguish The Environment
between sudden shocks and chronic (long-term) exposure to low pH levels. Sudden, short-term shifts in pH levels result from snowmelts, which release acidic materials accumulated during the winter, or sudden rainstorms that can wash residual acid into streams and lakes. The resulting acid shock can be devastating to fish and their ecosystems. At pH levels below 4.9, damage occurs to fish eggs. At acid levels below 4.5, some species of fish die. Below pH 3.5, most fish die within hours. (See Table 5.2.) Because many species of fish hatch in the spring, even mild increases in acidity can harm or kill the new life. Temporary increases in acidity also affect insects and other invertebrates, such as snails and crayfish, on which the fish feed. Gradual decreases of pH levels over time affect fish reproduction and spawning. Moderate levels of acidity in water can confuse a salmon’s sense of smell, which it Acid Rain
67
TABLE 5.1
Effects of acid rain on human health and selected ecosystems and anticipated recovery benefits Human health and ecosystem Human health
Effects
Recovery benefits
In the atmosphere, sulfur dioxide and nitrogen oxides become sulfate and nitrate aerosols, which increase morbidity and mortality from lung disorders, such as asthma and bronchitis, and impacts to the cardiovascular system. Acidic surface waters decrease the survivability of animal life in lakes and streams and in the more severe instances eliminate some or all types of fish and other organisms. Acid deposition contributes to forest degradation by impairing trees’ growth and increasing their susceptibility to winter injury, insect infestation, and drought. It also causes leaching and depletion of natural nutrients in forest soil. Acid deposition contributes to the corrosion and deterioration of buildings, cultural objects, and cars, which decreases their value and increases costs of correcting and repairing damage. In the atmosphere, sulfur dioxide and nitrogen oxides form sulfate and nitrate particles, which impair visibility and affect the enjoyment of national parks and other scenic views.
Surface waters
Forests
Materials
Visibility
Decrease emergency room visits, hospital admissions, and deaths.
Reduce the acidic levels of surface waters and restore animal life to the more severely damaged lakes and streams. Reduce stress on trees, thereby reducing the effects of winter injury, insect infestation, and drought, and reduce the leaching of soil nutrients, thereby improving overall forest health. Reduce the damage to buildings, cultural objects, and cars, and reduce the costs of correcting and repairing future damage. Extend the distance and increase the clarity at which scenery can be viewed, thus reducing limited and hazy scenes and increasing the enjoyment of national parks and other vistas.
“Appendix I. Effect of Acid Rain on Human Health and Selected Ecosystems and Anticipated Recovery Benefits,” in Acid Rain: Emissions Trends and Effects in the Eastern United States, U.S. General Accounting Office, Washington, DC, March 2000 SOURCE:
TABLE 5.2
Generalized short-term effects of acidity on fish pH range 6.5–9 6.0–6.4 5.0–5.9 4.5–4.9 4.0–4.4 3.5–3.9 3.0–3.4
Effect No effect Unlikely to be harmful except when carbon dioxide levels are very high (⬎1,000 mg I⫺1) Not especially harmful except when carbon dioxide levels are high (⬎20 mg I⫺1) or ferric ions are present Harmful to the eggs of salmon and trout species (salmonids) and to adult fish when levels of Ca2⫹, Na⫹ and Cl⫺ are low Harmful to adult fish of many types which have not been progressively acclimated to low pH Lethal to salmonids, although acclimated roach can survive for longer Most fish are killed within hours at these levels
“Generalized Short-Term Effects of Acidity on Fish,” in National Water Quality Inventory: 1998 Report to Congress, U.S. Environmental Protection Agency, Washington, DC, June 2000 SOURCE:
uses to find the stream from which it came. Atlantic salmon are unable to find their home streams and rivers because of acid rain. In addition, excessive acid levels in female fish cause low amounts of calcium, thereby preventing the production of eggs. Even if eggs are produced, their development is often abnormal. Over time the fish population decreases while the remaining fish population becomes older and larger. Increased acidity can also cause the release of aluminum and manganese particles stored in a lake or river bottom. High concentrations of these metals are toxic to fish. Soil and Vegetation
Acid rain is believed to harm vegetation by changing soil chemistry. Soils exposed to acid rain can gradually lose valuable nutrients, such as calcium, magnesium, and potassium, and become too concentrated with dissolved 68
Acid Rain
inorganic aluminum, which is toxic to vegetation. Longterm changes in soil chemistry may have already affected sensitive soils, particularly in forests. Forest soils saturated in nitrogen cannot retain other nutrients required for healthy vegetation. Subsequently, these nutrients are washed away. Nutrient-poor trees are more vulnerable to climatic extremes, pest invasion, and the effects of other air pollutants, such as ozone. Some researchers believe that acid rain disrupts soil regeneration, which is the recycling of chemical and mineral nutrients through plants and animals back to the Earth. They also believe acids suppress decay of organic matter, a natural process needed to enrich the soils. Valuable nutrients like calcium and magnesium are normally bound to soil particles and are, therefore, protected from being rapidly washed into groundwater. Acid rain, however, may accelerate the process of breaking these bonds to rob the soil of these nutrients. This, in turn, decreases plant uptake of vital nutrients. (See Figure 5.4.) Acid deposition can cause leafy plants such as lettuce to hold increased amounts of potentially toxic substances like the mineral cadmium. Research has also found a decrease in carbohydrate production in the photosynthesis process of some plants exposed to acid conditions. Research is underway to determine whether acid rain could ultimately lead to a permanent reduction in tree growth, food crop production, and soil quality. Effects on soils, forests, and crops are difficult to measure because of the numerous species of plants and animals, the slow rate at which ecological changes occur, and the complex interrelationships between plants and their environment. TREES. The effect of acid rain on trees is influenced by many factors. Some trees adapt to environmental stress better than others; the type of tree, its height, and
The Environment
FIGURE 5.4
Increasing nutrient flow
Relationship between soil acidity and nutrients
P
p ta tu lan
ke o
f nutrients
Loss of nutrients from s o
il s
Increasing soil acidity Note: As soil and deposition acidity increases, nutrients, such as base cations, are leached from the soil and are not available for plant growth. SOURCE: “Figure 18. Relationship between Soil Acidity and Nutrients,” in Progress Report on the EPA Acid Rain Program, U.S. Environmental Protection Agency, Air and Radiation, Washington, DC, November 1999
its leaf structure (deciduous or evergreen) influence how well it will adapt to acid rain. Scientists believe that acid rain directly harms trees by leaching calcium from their foliage and indirectly harms them by lowering their tolerance to other stresses. According to the EPA, acid rain has also been implicated in impairing the winter hardening process of some trees, making them more susceptible to cold-weather damage. In some trees the roots are prone to damage because the movement of acidic rain through the soil releases aluminum ions, which are toxic to plants. One area in which acid rain has been linked to direct effects on trees is from moist deposition via acidic fogs and clouds. The concentrations of acid and SO5 in fog droplets are much greater than in rainfall. In areas of frequent fog, such as London, significant damage has occurred to trees and other vegetation because the fog condenses directly on the leaves. Birds Increased freshwater acidity harms some species of migratory birds. Experts believe the dramatic decline of the North American black duck population since the 1950s is due to decreased food supplies in the acidified wetlands. The U.S. Fish and Wildlife Service reports that ducklings in wetlands created by humans in Maryland are three times more likely to die before adulthood if raised in acidic waters.
Acid rain leaches calcium out of the soil and robs snails of the calcium they need to form shells. Because The Environment
titmice and other species of songbirds get most of their calcium from the shells of snails, the birds are also perishing. The eggs they lay are defective—thin and fragile. The chicks either do not hatch or have bone malformations and die. In 2002 researchers at Cornell University released the results of a large-scale study showing a clear link between acid rain and widespread population declines in a songbird called the wood thrush. The scientists believe that calcium depletion has had a negative impact on the birds’ food source, mainly snails, earthworms, and centipedes. The birds may also be ingesting high levels of metals that are more likely to leach out of overly acidic soils. Declining wood thrush populations were most pronounced in the higher elevations of the Adirondack, Great Smoky, and Appalachian mountains. The researchers warned that acid rain may also be contributing to population declines in other songbird species. Materials Investigations into the effects of acid rain on objects such as stone buildings, marble statues, metals, and paints only began in the 1990s. A joint study conducted by the EPA, the Brookhaven National Laboratory, and the Army Corps of Engineers in 1993 found that acid rain was causing $5 billion worth of damage annually in a seventeen-state region. Two-thirds of the damage was created by pollution whose source was less than thirty miles away. Many of the country’s historical monuments and buildings are located in eastern states that have been most hard-hit by acid rain. Human Health Acid rain has several direct and indirect effects on human health. Particulates are extremely small pollutant particles that can threaten human health. Particulates related to acid rain include fine particles of SO5 and nitrates. These particles can travel long distances and, when inhaled, penetrate deep into the lungs. Acid rain and the pollutants that cause it can lead to the development of bronchitis and asthma in children. Acid rain is also believed to be responsible for increasing health risks to those over the age of sixty-five; those with asthma, chronic bronchitis, and emphysema; pregnant women; and those with histories of heart disease. THE POLITICS OF ACID RAIN Scientific research on acid rain was sporadic and largely focused on local problems until the late 1960s, when Scandinavian scientists began more systematic studies. Acid precipitation in North America was not identified until 1972, when scientists found that precipitation was acidic in eastern North America, especially in northeastern and eastern Canada. In 1975 the First International Symposium on Acid Precipitation and the Forest Acid Rain
69
Ecosystem convened in Columbus, Ohio, to define the acid rain problem. Scientists used the meeting to propose a precipitation-monitoring network in the United States that would cooperate with the European and Scandinavian networks and to set up protocols for collecting and testing precipitation. In 1977 the Council on Environmental Quality was asked to develop a national acid rain research program. Several scientists drafted a report that eventually became the basis for the National Acid Precipitation Assessment Program (NAPAP). This initiative eventually translated into legislative action with the Energy Security Act (PL 96–264) in June 1980. Title VII of the Energy Security Act (the Acid Precipitation Act of 1980) produced a formal proposal that created NAPAP and authorized federally financed support. The first international treaty aimed at limiting air pollution was the United Nations Economic Commission for Europe (UNECE) Convention on Long-Range Transboundary Air Pollution, which went into effect in 1983. It was ratified by thirty-eight of the fifty-four UNECE members, which included not only European countries but also Canada and the United States. The treaty targeted sulfur emissions, requiring that countries reduce emissions 30% from 1980 levels—the so-called ‘‘Thirty Percent Club.’’ The early acid rain debate centered almost exclusively on the eastern United States and Canada. The controversy was often defined as a problem of property rights. The highly valued production of electricity in coal-fired utilities in the Ohio River Valley caused acid rain to fall on land in the Northeast and Canada. An important part of the acid rain controversy in the 1980s was the adversarial relationship between U.S. and Canadian government officials over emission controls of SO2 and NO2. More of these pollutants crossed the border into Canada than the reverse. Canadian officials very quickly came to a consensus over the need for more stringent controls, while this consensus was lacking in the United States. Throughout the 1980s the major lawsuits involving acid rain all came from eastern states, and the states that passed their own acid rain legislation were those in the eastern part of the United States. Legislative attempts to restrict emissions of pollutants were often defeated after strong lobbying by the coal industry and utility companies. Those industries advocated further research for pollution-control technology rather than placing restrictions on utility company emissions. THE ACID RAIN PROGRAM—CLEAN AIR ACT AMENDMENTS, TITLE IV In 1980 Congress established NAPAP to study the causes and effects of acid deposition. About two thousand scientists worked with an elaborate multimillion70
Acid Rain
dollar computer model in an eight-year, $570 million undertaking. In 1988 NAPAP produced an overwhelming six-thousand-page report on its findings, including: • Acid rain had adversely affected aquatic life in about 10% of eastern lakes and streams. • Acid rain had contributed to the decline of red spruce at high elevations by reducing that species’ cold tolerance. • Acid rain had contributed to erosion and corrosion of buildings and materials. • Acid rain and related pollutants had reduced visibility throughout the Northeast and in parts of the West. The report concluded, however, that the incidence of serious acidification was more limited than originally feared. The Adirondacks area of New York was the only region showing widespread, significant damage from acid at that time. Results indicated that electricity-generating power plants were responsible for two-thirds of SO2 emissions and one-third of NO5 emissions. In response, Congress created the Acid Rain Program under Title IV (Acid Deposition Control) of the 1990 Clean Air Act Amendments (PL 101–549). The goal of the Acid Rain Program is to reduce annual emissions of SO2 and NOx from electric power plants nationwide. The program set a permanent cap on the total amount of SO2 that could be emitted by these power plants. That cap was set at 8.95 million tons (approximately half the number of tons of SO2 emitted by these plants during 1980). The program also established NOx emissions limitations for certain coal-fired electric utility plants. The objective of the NO5 program was to achieve and maintain a two-million-ton reduction in NO5 emission levels by the year 2000 compared with the emissions that would have occurred in 2000 if the program had not been implemented. The reduction was implemented in two phases. Phase 1 began in 1995 and covered 263 units at 110 utility plants in twenty-one states with the highest levels of emissions. Most of these units were at coal-burning plants in eastern and Midwestern states. They were mandated to reduce their annual SO2 emissions by 3.5 million tons. An additional 182 units joined Phase 1 voluntarily, bringing the total of Phase 1 units to 445. Phase 2 began in 2000. It tightened annual emission limits on the Phase 1 group and set new limits for more than two thousand cleaner and smaller units in all fortyeight contiguous states and the District of Columbia. A New Flexibility in Meeting Regulations Traditionally, environmental regulation has been achieved by the ‘‘command and control’’ approach, in which the regulator specifies how to reduce pollution, by The Environment
what amount, and what technology to use. Title IV, however, gave utilities flexibility in choosing how to achieve these reductions. For example, utilities could reduce emissions by switching to low-sulfur coal, installing pollutioncontrol devices called scrubbers, or shutting down plants.
FIGURE 5.5
SO2 allowance bank, 1995–2003
Allowances allocated that year
Allowance Trading Title IV also allows electric utilities to trade allowances to emit SO2. Utilities that reduce their emissions below the required levels can sell their extra allowances to other utilities to help them meet their requirements.
Title IV allows companies to buy, sell, trade, and bank pollution rights. Utility units are allocated allowances based on their historic fuel consumption and a specific emissions rate. Each allowance permits a unit to emit one ton of SO2 during or after a specific year. For each ton of SO2 discharged in a given year, one allowance is retired and can no longer be used. Companies that pollute less than the set standards will have allowances left over. They can then sell the difference to companies that pollute more than they are allowed, bringing them into compliance with overall standards. Companies that clean up their pollution would recover some of their costs by selling their pollution rights to other companies. The EPA holds an allowance auction each year. The sale offers allowances at a fixed price. This use of market-based incentives under Title IV is regarded by many as a major new method for controlling pollution. From 1995 to 1998 there was considerable buying and selling of allowances among utilities. Because the utilities that participated in Phase 1 reduced their sulfur emissions more than the minimum required, they did not use as many allowances as they were allocated for the first four years of the program. Those unused allowances could be used to offset SO2 emissions in future years. From 1995 to 1998 a total of 30.2 million allowances were allocated to utilities nationwide; almost 8.7 million, or 29%, of the allowances were not used but were carried over (banked) for subsequent years. Figure 5.5 shows the status of from 1995 through 2003. In 2003 a allowances were allocated. Another allowances were carried over from The Environment
the allowance bank total of 9.54 million 8.65 million banked previous years. The
Unused allowances from previous year (bank) Actual emissions from affected sources 25 21.6 SO2 emissions (million tons)
Utilities took advantage of their flexibility under Title IV to choose less costly ways to reduce emissions, such as switching from high- to low-sulfur coal, and they have been achieving sizable reductions in their SO2 emissions. Fifty-five percent of Phase 1 plants opted to switch to low-sulfur coal, 16% chose to install scrubbers, and only 3% initially planned to purchase allowances (which allow plants to emit extra SO2). Not surprisingly, the market for low-sulfur coal is growing as a result of Title IV, and the market for high-sulfur coal is decreasing.
19.9
20
18.8
18.2
2002
2003
16.6 15.0
15
13.5 11.7
10
8.7
5
0 1995
1996
1997
1998
1999
2000
2001
SOURCE: “Figure 2. SO2 Emissions and the Allowance Bank, 1995–2003,” in Acid Rain Program: 2003 Progress Report, U.S. Environmental Protection Agency, Office of Air and Radiation, Clean Air Markets Division, Washington, DC, September 2004, http://www .epa.gov/airmarkets/cmprpt/arp03/2003report.pdf (accessed June 14, 2005)
allowance bank reached a maximum during 2000 and began to decline after that. The EPA expects that the allowance bank will gradually be depleted. EMISSIONS AND DEPOSITION Each year the EPA publishes a report detailing the progress achieved by the Acid Rain Program. The latest report is titled Acid Rain Program, 2003 Progress Report and was published in September 2004.
The report notes that in 2003 there were 3,497 electric generating units subject to the SO2 provisions of the Acid Rain Program. They emitted 10.6 million tons of SO2 into the air as shown in Figure 5.6. The EPA expects that the 8.95-million-ton annual cap will be achieved by the year 2010. SO2 emissions from sources covered by the program decreased by 38% between 1980 and 2003. The downward trend in SO2 emissions was accompanied by a decrease in SO2 concentrations measured in the air and in sulfate deposition recorded at monitoring sites operated by the National Atmospheric Deposition Program. Between 1991 and 2003 average SO2 concentrations in the atmosphere decreased by 57% in the Northeast and 38% in the Mid-Atlantic states. Wet sulfate deposition declined by 39% in the Northeast and by 17% in the Southeast. Acid Rain
71
FIGURE 5.6
SO2 emissions regulated under the Acid Rain Program, 1980–2003
Phase I sources
All sources
Phase II sources
Allowances allocated for that year
20
SO2 emissions (million tons)
18
17.3 16.1
16
15.7
14 11.9
12
12.5
13.0 13.1
12.5 11.2
10
10.6 10.2 10.6
8 6 4
9.4
9.3
8.7 5.3
2
5.4
5.5
5.3
4.9
0 1980 1985 1990 1995 1996 1997 1998 1999 2000 2001 2002 2003
“Figure 1. SO2 Emissions Under the Acid Rain Program,” in Acid Rain Program: 2003 Progress Report, U.S. Environmental Protection Agency, Office of Air and Radiation, Clean Air Markets Division, Washington, DC, September 2004, http://www.epa.gov/ airmarkets/cmprpt/arp03/2003report.pdf (accessed August 4, 2005) SOURCE:
Between 1990 and 2003 NOx emissions from power plants subject to the Acid Rain Program decreased from 5.5 million tons per year to 3.8 million tons per year. This reduction was achieved even though the amount of fuel used to produce electricity increased by 30% over the same time period. In 2000 the program first achieved its goal of reducing emissions by at least two million tons; 8.1 million tons were originally predicted in 1990 to be emitted in the year 2000 without the program in place. Decreased NOx emissions have not resulted in uniformly lower levels of NOx in the atmosphere or in deposits measured at recording stations. The EPA reports ‘‘modest reductions’’ in these parameters in the Northeast and Mid-Atlantic states, but little improvement in the remainder of the country. ARE ECOSYSTEMS RECOVERING? Recovery Times The EPA reports that ecosystems harmed by acid rain deposition can take a long time to fully recover even after harmful emissions cease. The most chronic aquatic problems can take years to be resolved. Forest health is even slower to improve following decreases in emissions, tak-
72
Acid Rain
ing decades to recover from damage by acid deposition. Finally, soil nutrient reserves (such as calcium) can take centuries to replenish. Recent Studies Show Improvement In March 2000 the EPA and the U.S. Government Accountability Office (GAO) concluded in Acid Rain: Emissions Trends and Effects in the Eastern United States that some surface waters in New England harmed by acid rain were showing signs of recovery. However, ecosystems considered most severely affected—such as the Adirondacks—were not yet showing improvement at that time. The GAO reported that acidified lakes in the Adirondack Mountains were taking longer to recover than lakes elsewhere. Recovery was considered dependent on improving the nearby soil condition.
In late 2004 the EPA released a report on progress made by the United States and Canada on cross-border air pollution. The study, United States–Canada Air Quality Agreement: 2004 Progress Report, is the seventh biennial report related to the 1991 agreement between the two countries. The report says that SOx deposition was reduced in the Ohio River basin and southern Ontario and Quebec. Wet sulfate deposition was greatest along a line extending from the Mississippi River to the lower Great Lakes. The highest area of sulfate deposition was noted south of Lake Erie. In general the report notes that the trends in wet deposition of sulfate and nitrate correspond to the trends in emissions of SO2 and NOx. PUBLIC OPINION ABOUT ACID RAIN Every year the Gallup Organization polls Americans about their attitudes regarding environmental issues. The most recent poll to assess acid rain was conducted in March 2004. Participants were asked to express their level of personal concern about various environmental issues, including acid rain, water pollution, soil contamination, air pollution, plant and animal extinctions, loss of tropical rain forests, damage to the ozone layer, and global warming. The results showed that acid rain ranked last among these environmental problems. Only 20% of respondents expressed a great deal of worry about acid rain.
Analysis of historical Gallup poll results shows a dramatic decline in concern about acid rain since the late 1980s. In 1989 Gallup found that 41% of respondents felt a great deal of concern about acid rain and 11% felt none at all. By 2004 only 20% of people polled were concerned a great deal about acid rain and more than a quarter of those asked expressed no concern about the acid rain issue.
The Environment
CHAPTER 6
NONHAZARDOUS WASTE
One of the consequences of a modern society is the generation of enormous amounts of waste. The vast majority of this waste is not inherently hazardous. It includes paper, wood, plastics, glass, nonhazardous metals and chemicals, and other materials generated by industrial, commercial, agricultural, and residential sources. HISTORICAL PERSPECTIVE The earliest humans did not have garbage disposal problems. They lived in nomadic tribes, wandering the countryside and following herds of wild animals that they hunted and killed for food and clothing. Scavengers and insects ate their discarded food remains, and what was left decomposed. About twelve thousand years ago people began to form villages and become farmers. For the first time they had to live with their garbage, which smelled bad and attracted wild animals. Therefore, some villagers dug pits into which they tossed garbage. One of the best ways scientists learn about such prehistoric communities is by studying their garbage pits.
Around 500 B.C.E. (before the common era), Athens, Greece, issued the first known edict against throwing garbage into the streets and organized the first municipal dumps by mandating that scavengers transport wastes to no less than one mile from the walls of the city. This method was not practiced in medieval Europe (circa 500– 1485). Parisians in France and Londoners in England continued to toss trash and sewage out their windows until the 1800s. The west end of London and the west side of Paris became fashionable in the late seventeenth and eighteenth centuries because the prevailing winds blew west to east, carrying the smell of rotting garbage with them. Industrialization brought with it a greater need for collection and disposal of refuse. Garbage was transported beyond the city limits and dumped in piles in the The Environment
countryside. As cities grew, the noxious odors and rat infestations at the dumps became intolerable. Freestanding piles gave way to pits, but that solution soon became unsatisfactory. Throughout the nineteenth century many cities passed antidumping ordinances, but they were largely ignored. Some landowners and merchants resented ordinances, which they considered infringements of their rights. As cities grew so did garbage, becoming not only a public eyesore but a threat to public health. According to the Environmental Protection Agency’s (EPA) ‘‘Milestones in Garbage’’ timeline (http://www. epa.gov/epaoswer/non-hw/muncpl/timeline_alt.htm#2), the first U.S. garbage incinerator began operating in New York City during the late 1800s. By the time World War I began in Europe in 1914, about three hundred incinerators were operating in the United States and Canada. Although incineration reduced waste, the expense of building incinerators and the reduced air quality caused many cities to abandon this method of garbage management. Dumping garbage in rivers, lakes, wetlands, and oceans was widely practiced until the 1930s. In 1934 the U.S. Supreme Court banned the dumping of municipal solid waste (MSW) into oceans. Cities located downstream from other cities that were pouring their garbage into rivers sued the upstream cities because the water was polluted. As a result, cities began to build landfills or centralized garbage dumps to get rid of their waste. By 1945 the EPA reports that nearly one hundred cities around the country were using specially designed landfills for MSW disposal. Some health officials and reformers knew that pollution was unhealthy and could lead to sickness, but most people were not concerned about the long-term effects of garbage and pollution on the environment. As the twentieth century progressed, however, more and more Americans became concerned that garbage and pollution were harming the environment. 73
Development of a Throw-Away Society
Prior to the 1900s most Americans produced much less garbage than they do today. Food scraps were boiled to make soups or were fed to farm animals. Durable items were passed on to the next generation or to people in need. Objects that were of no further use to adults became toys for children. Broken items were repaired or dismantled for reuse. Grease was saved to make soap. Flour sacks were used for dishtowels or sewn into clothing, and jars were reused as drinking glasses. Combustible things that could no longer be used were burned for fuel, especially in the homes of the poor. Besides giving away clothes, mending and remaking them, and using them as rags for work, women reworked textiles into useful household furnishings, such as quilts, rugs, and upholstery. In the American culture of the time, such activities demonstrated a woman’s frugality and creative skill and came to represent an aspect of a woman’s virtue. A growing paper industry also made it profitable for thrifty housewives to save rags, which were used by paper mills to make paper. Even middle-class Americans traded rags to peddlers in exchange for buttons or teakettles. The ragmen worked the streets, begging for or buying at low prices items such as bones, paper, old iron, rags, and bottles. They then sold the junk to dealers who marketed it to manufacturers. A trade in used goods such as rags provided crucial resources for early industrialization. However, these early systems of recycling diminished in the early 1900s. Sanitary reformers and municipal trash collection did away with scavenging. Technology made cheap and new alternatives available. People made fewer things and bought more than did previous generations. They also saved and repaired less and threw out more. In A Social History of Trash (New York: Henry Holt and Co., 1999), Susan Strasser describes this change in the nation’s mindset: The rhetoric of convenience, luxury, and cleanliness was potent. It sold a wide variety of products that transformed Americans’ relationship to waste and, in general, to the material world. In a few decades, the ideal of the durable and reusable was displaced by aspirations of leisure and luxury, ease and cleanliness. The new ways were entrenched by 1929, in principle if not always in practice, and neither a depression nor the material shortages of a world war were enough to reverse what most people saw as progress.
Old-fashioned reuse and recycling did not cease overnight. During the first decades of the twentieth century, most people still threw away relatively little. Nonetheless, as the century progressed, middle-class people learned to discard things, attracted by convenience and a desire to avoid any association with scavenging and poverty. Success often meant that one did not have to use secondhand goods. As municipalities became responsible 74
Nonhazardous Waste
TABLE 6.1
Estimated life of selected consumer electronics [In years]
Range of primary and secondary use (reuse) life expectancy Video products Direct view color TV Projection TV LCD color TV Videocassette players VCR decks Camcorders Laserdisc players
13 to 15 13 to 15 13 to 15 7 to 10 7 to 10 7 to 10 7 to 10
Audio products Rack audio system Compact audio system Portable CD Portable headset audio Total CD players Home radios
3 to 15 3 to 15 3 to 15 3 to 15 3 to 15 3 to 15
Information products Cordless/corded telephones Wireless telephones Telephone answering machines Fax machines Personal word processors Personal computers Computer printers Computer monitors Modem/fax modems
3 to 6 2 to 4 3 to 6 3 to 6 3 to 6 3 to 6 3 to 5 6 to 7 3 to 6
“Table C-3. Estimated Life of Selected Consumer Electronics,” in Municipal Solid Waste in the United States: 2000 Facts and Figures, EPA530-R-02-001, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, June 2002. Data from Franklin Associates, Ltd. SOURCE:
for collecting and disposing of refuse, Americans found it easier to throw things away. By the 1920s technological and stylistic obsolescence began to characterize a growing number of consumer products. American markets were flooded with goods manufactured with the knowledge that they would become obsolete in a relatively short time. Henry Ford believed that ‘‘a Ford was forever.’’ He insisted that his Model T and Model A cars were ‘‘so strong and so well-made that no one ought ever to have to buy a second one.’’ Soon, however, it became evident that there was a substantial resale market for secondhand cars. Furthermore, it was quickly recognized that the industry could be more profitable if a person bought nine or ten cars over his or her lifetime rather than one or two. In her book Strasser notes that American society developed a ‘‘throwaway’’ mentality during the twentieth century as ‘‘more and more things were made and sold with the understanding that they would soon be worthless or obsolete.’’ Consumer electronics provide an excellent example of this. Table 6.1 shows the estimated life expectancy of some popular electronic products. None are expected to The Environment
TABLE 6.2
FIGURE 6.1
Total units shipped of selected consumer electronics, 1984–2000
Outline of the Resource Conservation and Recovery Act Subtitle A B C D E F G H I J
550,000 500,000 450,000 400,000 350,000 300,000 250,000 200,000 150,000 100,000 50,000 0
“Figure 1-3. Outline of the Act,” in RCRA Orientation Manual, EPA530-R-02-016, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, January 2003
98 19 9 20 9 00
97
TABLE 6.3
19
96
19
95
19
94
19
93
19
92
19
91
19
90
19
19
88 89 19
87
19
86
19
19
19
19
85
SOURCE:
84
Units shipped (1,000 units)
Units shipped
Provisions General provisions Office of Solid Waste; authorities of the administrator and Interagency Coordinating Committee Hazardous waste management State or regional solid waste plans Duties of the Secretary of Commerce in resource and recovery Federal responsibilities Miscellaneous provisions Research, development, demonstration, and information Regulation of underground storage tanks Standards for the tracking and management of medical waste
Year
“Figure C-1. Selected Consumer Electronics: Total Units Shipped 1984–2000,” in Municipal Solid Waste in the United States: 2000 Facts and Figures, EPA530-R-02-001, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, June 2002
Resource Conservation and Recovery Act’s interrelated programs
SOURCE:
Subtitle D
Subtitle C
Subtitle I
Solid waste program
Hazardous waste program
Underground storage tank program
“Figure 1-1. RCRA’s Three Interrelated Programs,” in RCRA Orientation Manual, EPA530-R-02-016, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, January 2003 SOURCE:
last for more than fifteen years. Sales of these products skyrocketed during the 1990s as shown in Figure 6.1. More than half a million units were shipped during 2000 alone. This means that millions of these products will enter the country’s waste system over the next two decades. The ‘‘throwaway society’’ mindset spurs industry to produce more. This results in greater amounts of industrial waste and greater usage of fossil fuels to generate power. All of these actions have profound effects on the nation’s environment. LAWS GOVERNING WASTE With antidumping ordinances being ignored throughout the 1800s and refuse piles growing, city leaders began to recognize that they had to do something about proper disposal. Most major cities had set up refuse collection systems by the turn of the century. Many cities introduced incinerators to burn some of the refuse, and by the 1920s landfilling had become a popular refuse disposal method. Cities often dumped their trash in nearby marshes and swamps, areas that were considered useless for development purposes.
In 1959 the American Society of Civil Engineers published Landfill Practice, a comprehensive manual about sanitary landfilling. The manual suggests that landfill waste be compacted and covered daily to prevent problems with rodents and odors. The Environment
In 1965 the United States government passed the Solid Waste Disposal Act, the first of many solid waste management laws. It was amended several times, most notably in 1976, with the Resource Conservation and Recovery Act (RCRA). Its primary goal was to ‘‘protect human health and the environment from the potential hazards of waste disposal.’’ RCRA is also concerned with reducing the amount of waste generated, ensuring that wastes are managed properly, and conserving natural resources and energy. The RCRA regulates solid waste, hazardous waste, and underground storage tanks containing petroleum products or certain chemicals. The RCRA definition of solid waste includes garbage and other materials ordinarily considered ‘‘solid,’’ as well as sludges, semisolids, liquids, and even containers of gases. These wastes can come from industrial, agricultural, commercial, and residential sources. The RCRA primarily covers hazardous waste, which is only a small part of all waste generated. State and local governments are mainly responsible for passing laws concerning nonhazardous waste, although the federal government will supply money and guidance to local governments so they can better manage their garbage systems. The RCRA consists of ten subtitles. (See Table 6.2.) As shown in Table 6.3, there are three subtitles covering the major programs regulated under RCRA: the solid Nonhazardous Waste
75
FIGURE 6.2
Examples of multi-exposure contamination pathways
Air contamination
Land contamination
Surface water contamination
Ground water contamination
Ground water contamination
“Figure VI-1. Multi-Exposure Pathways,” in RCRA Orientation Manual, EPA530-R-02-016, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, January 2003
SOURCE:
waste program (Subtitle D), the hazardous waste program (Subtitle C), and the underground storage tank program (Subtitle I). Subtitle D of RCRA assigns to the states responsibility for permitting and monitoring landfills for municipal solid waste and other nonhazardous wastes. Regulations established under Subtitle D describe minimum federal standards for the design, location, and operation of solid waste landfills to protect the environment. The states can develop their own permitting programs, so long as they include the federal landfill criteria. The EPA has the authority to review and approve the state programs. Subtitle C of RCRA gives the EPA primary responsibility for permitting facilities that treat, store, and/or dispose of hazardous waste. However, the EPA can allow states to operate their own permitting programs. Subtitle C regulations cover hazardous waste from the time it is created to the time of its final disposal. This is commonly called ‘‘cradle to grave’’ coverage. The Subtitle C regulations exempt certain kinds of hazardous waste (for example, hazardous wastes generated by households). Exempted hazardous wastes are covered by Subtitle D. Subtitle I is concerned with preventing, detecting, and cleaning up any releases from underground storage 76
Nonhazardous Waste
tanks holding petroleum products and hazardous substances. Subtitle I regulations include design standards for new tanks and upgrade requirements for existing tanks. The states can establish their own permitting programs with the approval of the EPA. Besides RCRA, other federal laws indirectly regulate waste disposal by protecting against pollution that can result from improper waste disposal practices. As shown in Figure 6.2, improper waste disposal can endanger the nation’s land, air, surface water, and groundwater resources. The Federal Water Pollution Control Act was originally enacted in 1948 and totally revised by amendments in 1972, giving the Clean Water Act its current form. Another set of amendments to this law is the Water Quality Act of 1987. These acts provide legislation to protect against the pollution of America’s lakes, rivers, coastal areas, and aquifers (underground areas of water). The Safe Drinking Water Act, enacted in 1974, protects the quality of drinking water in the United States and controls underground injections (when wastewater is injected into deep wells). The Clean Air Act of 1990 establishes federal standards for autos and other mobile sources of air pollution; for sources of hazardous air pollutants; and for the The Environment
FIGURE 6.3
FIGURE 6.4
Non-hazardous waste
Distribution of solid waste, 1992
Industrial hazardous waste 2%
Petroleum 3%
Municipal solid waste 1% Stone, clay & glass 10%
Chemicals 22%
Primary metals 21%
Industrial solid waste 57%
Special wastes 39%
SOURCE: Solid Waste: State and Federal Efforts to Manage Nonhazardous Waste, U.S. General Accounting Office, Washington, DC, 1995
emissions that cause acid rain. This legislation began as the Air Pollution Control Act of 1955 and the Clean Air Act of 1963, with a major revision of the legislation in 1970. It is difficult to calculate exactly how much waste is generated in the United States and what becomes of it. Under RCRA the federal government collects data on the production and management of hazardous waste. These data are supplied by the industries and businesses generating the waste. In addition, the EPA estimates the production of municipal solid waste (common garbage) each year using surveys, studies, population data, and other information (see below). However, both of these ‘‘waste streams’’ are thought to be very small in comparison to the amount of industrial nonhazardous waste that is generated. The EPA reported that the country generated a total of thirteen billion tons of solid waste in 1992 (Solid Waste: State and Federal Efforts to Manage Nonhazardous Waste, GAO, Washington, DC, 1995). Municipal solid waste and industrial hazardous waste made up only small fractions of this total, as shown in Figure 6.3. Special waste constituted more than a third of the total. These are waste materials specifically defined by federal law that result from mining, oil and gas production, electric utilities, and cement kilns. Special wastes are considered to have a low hazard to the environment and receive special consideration under the RCRA rules. The majority of the waste produced in 1992 was industrial nonhazardous waste. The Environment
Pulp & paper 34%
Other 10%
SOURCE: Adapted from “Figure W-1. Non-Hazardous Waste,” in “Waste Generation,” Energy, Environmental and Economics (E3) Handbook, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Office of Industrial Technology, Washington, DC, September 1997
INDUSTRIAL NONHAZARDOUS WASTES The majority of solid waste produced in the United States comes from industrial sources and is nonhazardous. Federal law specifically defines what constitutes hazardous waste and municipal solid waste. Nonhazardous industrial wastes are those waste materials that do not fall into either of these definitions. Figure 6.4 shows a general breakdown of nonhazardous industrial waste by material, as reported by the Office of Industrial Technology.
Manufacturing produces huge amounts of nonhazardous waste. The paper industry, which uses many chemicals to produce paper, accounts for a very large proportion of manufacturing waste. The metal and chemical industries are also large waste producers. Many big manufacturing plants have sites on their own property where they dispose of waste or treat it so it will not become dangerous. Still others ship it to private disposal sites for dumping or for treatment. Smaller manufacturers might use private waste disposal companies or even the city garbage company. State and local governments have regulatory responsibility for the management of most nonhazardous wastes. Different states have different regulatory schemes. For example, Texas categorizes nonhazardous industrial wastes into three classes based on their potential harm to the environment and human health. Class 1 wastes include asbestos, ash, and various solids, sludges, and liquids contaminated with nonhazardous chemicals. Every four years the state evaluates its disposal capacity Nonhazardous Waste
77
TABLE 6.4
Generation, materials recovery, composition, and discards of municipal solid waste in millions of tons and percent of total generation, 1960–2003 1960
1970
1980
1990
1995
2000
2001
2002
2003
88.1 5.6 Neg. 5.6 82.5
121.1 8.0 Neg. 8.0 113.0
151.6 14.5 Neg. 14.5 137.1
205.2 29.0 4.2 33.2 172.0
213.7 46.2 9.6 55.8 158.0
234.0 52.4 16.5 68.9 165.1
231.2 52.8 16.6 69.3 161.9
235.5 53.8 16.7 70.5 165.0
236.2 55.4 16.9 72.3 163.9
100.0% 6.6% Neg. 6.6% 93.4%
100.0% 9.6% Neg. 9.6% 90.4%
100.0% 14.2% 2.0% 16.2% 83.8%
100.0% 21.6% 4.5% 26.1% 73.9%
100.0% 22.4% 7.0% 29.4% 70.6%
100.0% 22.8% 7.2% 30.0% 70.0%
100.0% 22.8% 7.1% 29.9% 70.1%
100.0% 23.5% 7.1% 30.6% 69.4%
Millions of tons Generation Recovery for recycling Recovery for composting* Total materials recovery Discards after recovery Percent of total generation Generation Recovery for recycling Recovery for composting* Total materials recovery Discards after recovery
100.0% 6.4% Neg. 6.4% 93.6%
Notes: *Composting of yard trimmings, food scraps, and other MSW organic material. Does not include backyard composting. Details may not add to totals due to rounding. SOURCE: Adapted
from “Table 1. Generation, Materials Recovery, Composting, and Discards of Municipal Solid Waste, 1960–2003 (in millions of tons),” and “Table 2. Generation, Materials Recovery, Composting, and Discards of Municipal Solid Waste, 1960–2003, in Percent of Total Generation,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/msw05rpt.pdf (accessed August 4, 2005)
for Class 1 wastes. The last report available was published in 2000 and includes data for 1997. According to Needs Assessment for Industrial Class 1 Nonhazardous Waste Commercial Disposal Capacity in Texas (2000 Update), nearly eighty-three million tons of Class 1 waste were generated in Texas that year. The vast majority of the waste (96%) was liquid. Class 2 wastes include containers that held Class 1 wastes, depleted aerosol cans, some medical wastes, paper, food wastes, glass, aluminum foil, plastics, Styrofoam, and food packaging resulting from industrial processes. Class 3 wastes include all other chemically inert and insoluble substances such as rocks, brick, glass, dirt, and some rubbers and plastics. Industries do not have to report how much Class 2 or Class 3 wastes they generate or how they dispose of it. However, municipal solid waste landfills are required to report the receipt of all industrial waste. MUNICIPAL SOLID WASTE The EPA defines municipal solid waste (MSW) as ‘‘common garbage or trash.’’ MSW includes items like food scraps, paper, containers and packaging, appliances, batteries, and yard trimmings. These types of wastes are generally collected and managed by local municipal agencies. MSW does not include construction and demolition wastes, automobile bodies, sludge, combustion ash, and industrial process wastes.
Determining the amount and types of MSW generated in the United States is a very difficult task. People are not required to track or report how much MSW they produce 78
Nonhazardous Waste
or what it contains. The EPA uses information supplied by trade groups and industrial sources, combined with estimated product life spans and population and sales data, to estimate how much and what types of MSW are generated. The EPA publication Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003 (April 2005) reports that Americans produced 236.2 million tons of MSW in 2003, up slightly from 235.5 million tons in 2002. (See Table 6.4.) The tons of MSW generated annually increased dramatically between 1960 and 2000. Most of this increase occurred during the 1960s, 1970s, and 1980s. In 1960 just over eighty-eight million tons of MSW were generated. Over the next three decades, MSW generation increased on average by 32% per decade. However, the 1990s witnessed a slowdown in this rate of increase. MSW generation increased by only 13% between 1990 and 2000 and then leveled off in the early 2000s. This trend is also reflected in the per capita (per person) values for MSW generation. In 1960 each American generated on average 2.68 pounds of MSW per day. That value steadily increased until 1990, when it reached 4.50 pounds per day. The rate leveled off during the 1990s as shown in Figure 6.5, fluctuating between 4.40 and 4.64 pounds. In 2003 per capita generation was 4.5 pounds per day. This number has remained fairly constant since 1990. MSW COMPOSITION Figure 6.6 shows EPA estimates of the breakdown of MSW produced in 2003 by waste type. Paper was the largest single component by weight, comprising 35.2% of The Environment
glass (5.3%), and other MSW (3.4%). The top five categories—paper, yard trimmings, food scraps, plastics, and metals—together comprise more than three-fourths of the MSW generated in 2003.
FIGURE 6.5
Trends in total and per capita municipal solid waste generation, 1960–2003
Paper
Total municipal solid waste generation
250
10.00
200
8.00
150
6.00
100
4.00
50
2.00
0
0.00 1960 1970 1980 1990 1995 2000 2001 2002 2003
Per capita generation (lbs/person/day)
Total municipal solid waste generation (million tons)
Per capita generation
SOURCE: “Figure 1. MSW Generation Rates from 1960 to 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/ muncpl/pubs/msw05rpt.pdf (accessed August 4, 2005)
FIGURE 6.6
Breakdown by waste type of municipal solid waste generated, 2003
Rubber, leather, and textiles 7.4%
Wood 5.8%
Yard trimmings 12.1%
Food scraps 11.7%
Plastics 11.3%
Other 3.4%
Paper 35.2%
Metals 8.0%
Glass 5.3% Note: Total MSW was 236 million tons (before recycling).
“Figure 3. 2003 Total MSW Generation—236 Million Tons (Before Recycling),” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa .gov/epaoswer/non-hw/muncpl/pubs/msw05rpt.pdf (accessed August 4, 2005)
The EPA estimates that in 2003 there were 83.1 million tons of paper generated as MSW. The paper category includes numerous paper and paperboard (boxboard and containerboard) products as shown in Table 6.5. Corrugated boxes make up the bulk of this category in terms of the tons generated. In 2003 MSW included 29.7 million tons of corrugated boxes, representing 36% of the entire paper category. Newspapers, office papers, commercial printing papers, milk cartons, and junk mail are other major contributors to the paper category. This category does not include gypsum wallboard facings (which are classified as construction and demolition debris) or toilet tissue (which goes to sewage treatment plants). Yard Trimmings
EPA estimates show that in 2003 there were 28.6 million tons of yard trimmings generated as MSW. Yard trimmings include grass, leaves, and tree and brush trimmings from residential, commercial, and institutional sources. According to the EPA, yard trimmings are assumed to contain an average by weight of 50% grass, 25% leaves, and 25% brush. In the past the EPA based its estimates of yard trimming generation on only sampling studies and population and housing data. During the 1990s it began to take into account the expected effects of local and state legislation on yard trimmings disposal in landfills. For example, in 1992 only eleven states and the District of Columbia had laws prohibiting or discouraging residents from disposing yard trimmings at landfills. By 1997 another twelve states had such legislation in place. The EPA believes that this increased the use of mulching lawnmowers and the practice of backyard composting of yard trimmings, thus reducing the amount of yard trimmings in MSW. Food Scraps
SOURCE:
the waste stream. It was followed by yard trimmings (12.1%), food scraps (11.7%), plastics (11.3%), metals (8%), rubber, leather, and textiles (7.4%), wood (5.8%), The Environment
The EPA estimates that in 2003 there were 27.6 million tons of food wastes generated in MSW. Included in EPA’s definition of food scraps are uneaten food and food preparation scraps from residences, commercial establishments (such as restaurants and grocery stores), institutional sources (such as school cafeterias and prisons), and industrial sources (such as factory cafeterias). Food scraps generated by industrial sources that produce and package food products are not included in MSW. Nonhazardous Waste
79
• Bags, sacks, and wraps—16%
TABLE 6.5
Breakdown by type of paper and paperboard products generated in municipal solid waste, 2003
Product category
Generation (thousand tons)
Nondurable goods Newspapers Newsprint Groundwood inserts
10,260 2,380
Total newspapers
12,640
Books Magazines Office papers Telephone directories Standard (A) maila Other commercial printing Tissue paper and towels Paper plates and cups Other nonpackaging paperb
1,030 2,270 7,150 640 5,400 6,950 3,250 970 3,960
Total paper and paperboard nondurable goods
44,260
Containers and packaging Corrugated boxes Milk cartons Folding cartons Other paperboard packaging Bags and sacks Other paper packaging
29,710 450 5,560 180 1,230 1,700 38,830
Total paper and paperboard
83,090
a
Formerly called Third Class Mail by the U.S. Postal Service. Includes tissue in disposable diapers, paper in games and novelties, cards, etc. Details may not add to totals due to rounding. b
Adapted from “Table 4. Paper and Paperboard Products in MSW, 2003 (In Thousands of Tons and Percent of Generation),” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: 2003 Data Tables, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/ epaoswer/non-hw/muncpl/pubs/03data.pdf (accessed August 4, 2005) SOURCE:
Plastics The EPA estimates that in 2003 there were 26.7 million tons of plastic materials in the MSW waste stream. The term ‘‘plastics’’ refers to materials made from particular chemical resins that can be molded or shaped into various products. Plastic materials are found in a wide variety of products, including containers, packaging, trash bags, milk jugs, cups, eating utensils, disposable diapers, sporting and recreational equipment, and many common household items (such as shower curtains). In addition there are plastic components in appliances, computers, furniture, luggage, and many other consumer products.
The EPA classifies plastic materials generated in the MSW in two ways—by product type and by resin. The product types are listed below along with the corresponding percentage that each comprised of the plastics waste stream: • Nondurable goods—24% 80
Nonhazardous Waste
• Other containers—11% • Soft drink, water, and milk containers—7% Durable goods are those with a life expectancy in excess of three years (such as appliances and luggage). Nondurable goods are items with a life expectancy of less than three years (such as disposable diapers). Note that plastics used in automobiles and other vehicles are not included in these totals. In addition, the EPA classifies plastics by their resin type. Although there are dozens of resin types, the most common are listed below along with the corresponding percentage of each found in the plastics waste stream: • Low-density polyethylene (LDPE)/Linear low-density polyethylene (LLDPE)—23% • High-density polyethylene (HDPE)—19% • Other resins—19% • Polypropylene (PP)—14% • Polyethylene terephthalate (PET)—11%
Total paper and paperboard containers and packaging
• Durable goods—31%
• Other packaging—11%
• Polystyrene (PS)—9% • Polyvinyl chloride (PVC)—6% PET is widely used to make soft drink bottles, while HDPE is commonly used in milk jugs. Many people are familiar with the plastic PVC, because household piping is made from it. Metals EPA estimates show that in 2003 there were 18.8 million tons of metals generated in MSW. Ferrous metals (iron and steel) comprised 74% of this category by weight, followed by aluminum at 17% and other nonferrous (non-iron) metals at 8%. Ferrous metals are widely used in durable goods such as appliances and furniture. Ferrous metals used in transportation vehicles (such as automobiles) are not included in this category. Steel is also used to manufacture food cans, barrels, and drums. Aluminum found in MSW is most commonly in beer and soft drink cans, food cans, and as foil wrap. Consumer Electronics Consumer electronics include televisions, computers, VCRs, CD and DVD players, digital and video cameras, radios, answering machines, telephones and cellular phones, fax machines, printers, scanners, and miscellaneous other equipment. Historically, such products have been lumped with other products in EPA’s report under the category ‘‘other miscellaneous durable goods.’’
In 1999 for the first time consumer electronics were categorized separately, and it was estimated that 1.7 The Environment
FIGURE 6.7
Breakdown of materials generated in municipal solid waste, 1960–2003
Yard
Plastics
Glass
Food
Metals
Paper
The total number of pounds of plastic in MSW increased from only 390,000 tons in 1960 to 26.7 million tons in 2003. Most of these plastics (a family of more than forty-five types) are nonbiodegradable and, once discarded, remain relatively intact for many years. They do not break down through organic processes.
All other*
250
200
Million tons
are increasingly using plastic to package their products because plastic is so easy to use and to shape. As a result, plastics are the fastest-growing proportion of MSW in the United States. The EPA predicts that the amount of plastic thrown away will continue to increase.
The percentage of yard trimmings in the MSW total decreased from 22.7% in 1960 to 12.1% in 2003. However, the tons of yard trimmings in MSW actually increased over this time period.
150
100
50
0 1960
MSW MANAGEMENT 1965
1970
1975
1980
1985
1990
1995
2000
*All other includes primarily wood, rubber and leather, and textiles. SOURCE: “Figure 10. Generation of Materials in MSW, 1960 to 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: 2003 Data Tables, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/ 03data.pdf (accessed August 4, 2005)
million tons entered the MSW stream. In 2003 this value climbed to 2.5 million tons, representing 1.5% of the total MSW generated. Although this percentage is small, it is expected to increase quickly during the 2000s as more products reach the end of their useful lives. The average electronic product is assumed to be 44% metal, 32% plastic, 15% glass, 9% wood, and 1% other components. (Note that the total exceeds 100% due to rounding.) Historical Trends in MSW Composition Figure 6.7 shows EPA estimates of MSW composition for various years between 1960 and 2003. Paper has consistently been the largest single component of MSW generated. According to the EPA, paper’s share of the total increased slightly from 34% in 1960 to 35.2% in 2003. Most of the other categories have also experienced small changes (either up or down) in percentage of total generation. The notable exceptions are plastics and yard trimmings (http://www.epa.gov/epaoswer/non-hw/ muncpl/pubs/msw05rpt.pdf ).
In 1960 plastics comprised only 0.4% of the total MSW generated. By 2003 they comprised 11.3% of the MSW total. This is an enormous increase. Today, more plastics are produced in the United States than aluminum and all other nonferrous metals combined. Manufacturers The Environment
The three primary methods for the management of MSW are: • Land disposal • Combustion (or incineration) • Recovery through recycling or composting Land disposal involves piling or burying waste materials on or below the ground surface. This is primarily done at facilities called landfills. Combustion is the burning of waste to produce energy. Incineration is a disposal method in which MSW is burned at high temperatures. Recycling is the reuse of a material in another product or application. Composting is a method of decomposing yard trimmings and other biodegradable wastes for reuse as fertilizer. According to the EPA, in 2003 land disposal was the most common method used to manage MSW in the United States. (See Figure 6.8.) More than half (55.4%) of the MSW generated went to land disposal, while 30.6% was recovered, and 14% was combusted. The EPA does not break down MSW disposal methods by region or state. However, the journal BioCycle provided regional information on disposal methods for 2002 in its article ‘‘The State of Garbage in America’’ (Scott M. Kaufman, Nora Goldstein, Karsten Millrath, and Nickolas J. Themelis, January 2004). Landfilling is most prevalent in the Rocky Mountain and Midwestern states. In general, these states are less densely populated, thus they generate less MSW and have more space for landfills than many other states. Combustion and incineration were more common in the New England and Mid-Atlantic states. These states are much more densely populated and have few areas available or suitable for landfilling. Nonhazardous Waste
81
FIGURE 6.8
Management methods for municipal solid waste, 2003
How Organic Matter Decomposes in Landfills Organic material (material that was once alive, such as paper and wood products, food scraps, and clothing made of natural fibers) decomposes in the following way: first, aerobic (oxygen-using) bacteria use the material as food and begin the decomposition process. Principal by-products of this aerobic stage are water, carbon dioxide, nitrates, and heat. This stage lasts about two weeks. However, in compacted, layered, and covered landfills, the availability of oxygen may be low.
Recovery 30.6%
Land disposal 55.4%
wastes in MSW are not biodegradable. Landfills provide a centralized location in which these wastes can be contained.
Combustion 14.0%
SOURCE: “Figure 6. Management of MSW in the United States—2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: 2003 Data Tables, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/ msw05rpt.pdf (accessed August 4, 2005)
Table 6.6 shows EPA’s estimates of the percentages of MSW landfilled, combusted, and recovered from 1960 to 2003. The proportion of MSW that is recovered through recycling and composting has grown over the decades, while combustion and landfill use have declined. MUNICIPAL (OR SANITARY) LANDFILLS
Municipal (or sanitary) landfills are areas where MSW waste is placed into and onto the land. While some landfilled organic wastes will decompose, many of the
After the available oxygen is used, anaerobic bacteria (those that do not use oxygen) continue the decomposition. They generally produce carbon dioxide and organic acids. This stage can last up to one to two years. During a final anaerobic stage of decomposition lasting several years or decades, methane gas is formed along with carbon dioxide. The duration of this stage and the amount of decomposition depend on landfill conditions, including temperature, soil permeability, and water levels. In July 1992 The Smithsonian reported on a twentyyear study called the Garbage Project. Conceived in 1971 and officially established at the University of Arizona in 1973, the Garbage Project was an attempt to apply archaeological principles to the study of solid waste. About 750 people processed more than 250,000 pounds of waste, excavating fourteen tons of it from landfills. Among the Garbage Project’s findings was the discovery that although some degradation takes place initially (sufficient to produce large amounts of methane and other gases), it then slows to a virtual standstill. Study
TABLE 6.6
Generation, materials recovery, combustion, and discards of municipal solid waste, 1960–2003 [In percent of total generation]
Total generation Total materials recovery Combustiona Discards to landfill, other disposalb Total discards after recovery
1960
1970
1980
1990
1995
2000
2001
2002
2003
100.0% 6.4% 30.6%
100.0% 6.6% 20.7%
100.0% 9.6% 9.0%
100.0% 16.2% 15.5%
100.0% 26.1% 16.6%
100.0% 29.4% 14.4%
100.0% 30.0% 14.5%
100.0% 29.9% 14.2%
100.0% 30.6% 14.0%
63.0%
72.6%
81.4%
68.3%
57.3%
56.2%
55.5%
55.9%
55.4%
93.6%
93.4%
90.4%
83.8%
73.9%
70.6%
70.0%
70.1%
69.4%
a
Includes combustion of MSW in mass burn or refuse-derived fuel form, and combustion with energy recovery of source separated materials in MSW (e.g., wood pallets and tire-derived fuel). Discards after recovery minus combustion. Details may not add to totals due to rounding. b
“Table 7. Generation, Materials Recovery, Combustion, and Discards of Municipal Solid Waste, 1960–2003 (in Percent of Total Generation),” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/msw05rpt.pdf (accessed August 4, 2005) SOURCE:
82
Nonhazardous Waste
The Environment
results revealed that an astonishingly high volume of old organic matter remained largely intact. Even after two decades, one-third to one-half of supposedly degradable organics remained in recognizable condition. The Smithsonian Institution concluded that well-designed and wellmanaged landfills, in particular, seemed more likely to preserve their contents than to transform them into humus or mulch. Landfills and the Environment
Methane, a flammable gas, is produced when organic matter decomposes in the absence of oxygen. If not properly vented or controlled, it can cause explosions and underground fires that smolder for years. Methane is also deadly to breathe. The RCRA requires landfill operators to monitor methane gas. METHANE.
The Smithsonian Garbage Project found that for fifteen or twenty years after a landfill stops accepting garbage, the wells still vent methane in fairly substantial amounts. Thereafter, methane production drops off rapidly, indicating that the landfill has stabilized. Methane gas can be recovered through pipes inserted into landfills, and the gas can be used to generate energy. As of January 2005, there were 375 operational landfill gas-to-energy projects in the United States. The EPA’s Landfill Methane Outreach Program estimates that more than six hundred other landfill sites present attractive opportunities for project development. Figure 6.9 shows the number of operational and candidate landfills in each state. Cadmium is a natural element in the Earth’s crust that is frequently found in municipal waste. It has uses in many products, including batteries, pigments, plastics, and metal coatings. The EPA estimates that 2,680 tons of cadmium had been deposited in MSW by 2000. Most cadmium in MSW comes from the disposal of batteries. The remainder comes from plastics, consumer electronics, pigments, appliances, glass, and ceramics. CADMIUM.
When ingested by humans in polluted air or water, cadmium can build up in the human body over years, damaging the lungs, kidneys, nervous system, and stomach. It is classified by the EPA as a probable human carcinogen (cancer-causing agent) and has been associated with the development of lung cancer. Lead is an environmental contaminant found in municipal waste that can damage virtually every human organ system. A naturally occurring metal found in small amounts in the Earth’s surface, lead is used in many products including lead-acid batteries, consumer electronics, glass and ceramics, plastics, cans, and pigments. The EPA estimates in 2000 there were 1.9 million tons of lead-acid batteries in MSW. LEAD.
The Environment
Another component of MSW is mercury. Mercury is a naturally occurring metal that is found both in liquid and gas form. It is used to produce chlorine gas and is used in the manufacturing of many products. Once in ground and surface water, it accumulates in fish that humans may eat. It harms the human nervous system and other body organs. The EPA estimates that 172.7 tons of mercury was discarded in waste in 2000. Most of that came from household batteries, thermometers, electronics, paint residues, and pigments. MERCURY.
In 1996 Congress passed the Mercury-Containing and Rechargeable Battery Management Act (known as the ‘‘battery recycling bill’’). This law phased out the use of mercury in batteries. Landfill Design Standards The RCRA standards require landfill operators to do several things to lessen the chance of polluting the underlying groundwater. Groundwater can become contaminated when liquid chemicals or contaminated rainfall runoff seep down through the ground underneath the landfill. This liquid is called leachate.
The RCRA requirements are as follows: • Landfill operators must monitor the groundwater for pollutants. This is usually accomplished with a groundwater monitoring well system. • Landfills must have plastic liners underneath their waste, as well as a leachate collection system. (See Figure 6.10.) • Debris must be covered daily with soil to prevent odors and stop refuse from being blown away. • Methane gas (a by-product of decomposition) must be monitored, which is usually accomplished with an explosive-gas monitoring well. • Landfill owners are responsible for cleanup of any contamination. Landfills are not open dumps but rather managed facilities in which wastes are controlled. MSW is often compacted before it is placed in a landfill, and it is covered with soil. Modern landfills have liner systems and other safeguards to prevent groundwater contamination. When they are full, landfills are usually capped with a clay liner to prevent contamination. (See Figure 6.10.) Imports and Exports of Garbage Lack of landfill space has encouraged some municipalities to send their garbage to other states. Although shipments do occur across the Mexican and Canadian borders, the vast majority of American MSW is managed within the United States.
According to BioCycle, importing and exporting MSW from state to state is very common. In 2002 New Nonhazardous Waste
83
FIGURE 6.9
Status of landfill gas energy projects by state, January 2005
Operational projects
Candidate landfills
WA 6 8 6 * NH
MT 0
ND
5
7
4
1
1
OR ID
5 1
CA 73 46
5
3
AZ 12
NM 0 2
6
4
20
4
OK 14
KY
4
18
3
RI 2 * CT 2
6
NJ 11
4
DE 1
3
MD 4
12
SC 3 12 GA
LA 3
22
5
18
12
LA 2
VA 15 15
4
NC 11 35
13
4 MS 0
11 FL 10 18
AK 0
5
TN
AR 1
TX 18 55
WV 15 15
17
MO
PA 22 20
OH 18 26
IL 15
IL 36 25
KS 3
4
12
5
CO 0 13
NY 16 23
MI 26 10
IA 1
UT
ME 0
MA 17
WI 13 13
NE
NV
1 VT
7
4
2
0
WY 0 1
0
2
SD
2
1
MN
1 Puerto Rico 0 0
8 HI
National summary 381 operational projects 600 candidate landfills have 18 MMTCE* potential
6
U.S. Virgin Islands
0
2
*MMTCE is million metric tons of carbon equivalent.
“Status of Landfill Gas Energy Project Development and Candidate Landfills by State,” in Landfill Methane Outreach Program: Energy Projects and Candidate Landfills, U.S. Environmental Protection Agency, Washington, DC, June 30, 2005, http://www.epa.gov/lmop/proj/index.htm (accessed August 4, 2005)
SOURCE:
York exported the most MSW (5.4 million tons), followed by New Jersey (3.5 million tons) and Missouri (1.99 million tons). Other states exporting more than one million tons of MSW included Maryland (1.94 million tons), Massachusetts (1.7 million tons), and Washington (1.1 million tons). The chief MSW importers were Pennsylvania (ten million tons), Illinois (5.8 million tons), Virginia (4.5 million tons), and Michigan (3.8 million tons). The vast majority of imported MSW was landfilled. Several states have tried to ban the importing of garbage into their states. In 1992 the Supreme Court ruled in Chemical Waste Management Inc. v. Hunt (504 84
Nonhazardous Waste
U.S. 334, 1992) that the constitutional right to conduct commerce across state borders protects such shipments. Experts point out that newer, state-of-the-art landfills with multiple liners and sophisticated pollution control equipment have to accept waste from a wide region to be financially viable. Trends in Landfill Development
Prior to using landfills, cities used open dumps, areas in which garbage and trash were simply discarded in huge piles. However, open dumps produced unpleasant odors and attracted animals. In the early 1970s the number of operating landfills in the United States was The Environment
FIGURE 6.10
Example of a properly closed landfill
When landfill is full, layers of soil and clay seal in trash.
Topsoil Sand Clay Garbage
Wells and probes to detect leachate or methane leaks outside landfill.
Pipes collect explosive methane gas, used as fuel to generate electricity.
Cutaway view of a modern landfill designed to prevent the two main hazards of the dump: explosions or fires caused by methane gas, and leakage of rainwater mixed with dangerous chemicals (or leachate).
Leachate pumped up to storage tank for safe disposal.
Garbage Sand Synthetic liner Sand Clay
Clay and plastic lining to prevent leaks; pipes collect leachate from bottom of landfill.
Subsoil
“Diagram 1. Example of a Properly Closed Landfill,” in Fact Flash 6: Resource Conservation and Recovery Act, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, 1999
SOURCE:
estimated at about twenty thousand. In 1979, as part of the RCRA, the EPA designated conditions under which solid waste disposal facilities and practices would not pose adverse effects to human health and the environment. As a result of the implementation of these criteria, open dumps had to be closed or upgraded to meet the criteria for landfills. Additionally, many more landfills closed in the early 1990s because they could not conform to the new standards that took effect in 1993 under the 1992 RCRA amendment. Other landfills closed as they became full. According to the EPA, the number of landfills available for MSW disposal decreased dramatically between 1988 and 2003 from 7,924 to 1,767. (See Figure 6.11.) Landfilling is expected to continue to be the single most predominant MSW management method. In the coming decades, it will be economically prohibitive to The Environment
develop and maintain small-scale, local landfills. There will likely be fewer, larger, and more regional operations. More MSW is expected to move away from its point of generation, resulting in increased import and export rates. Although the United States is one of the least crowded industrialized nations in the world, in terms of population density per acre, population density and available landfill space vary widely across the country. New areas for landfills are becoming increasingly hard to find in some areas of the country (such as the Northeast), while other states have plenty of landfill space available. A few states (Connecticut, Massachusetts, New Jersey, and Rhode Island) have insufficient land with suitable soil and water conditions for landfills. Since landfills are not welcome in most neighborhoods, useable land must be found away from residential areas. Several states in the Northeast and Midwest have very little landfill capacity remaining. Nonhazardous Waste
85
FIGURE 6.11
Number of landfills in the United States by year, 1988–2002
7,924
8,000
7,379 7,000 6,326 5,812
6,000
5,386 5,000
4,482
4,000
3,558 3,197
3,091
3,000
2,514
2,314
2,216
2,000
1,967
1,858
1,767
2000
2001
2002
1,000 0 1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
“Figure 5. Number of Landfills in the United States by Year,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http:// www.epa.gov/epaoswer/non-hw/muncpl/pubs/msw05rpt.pdf (accessed June 22, 2005)
SOURCE:
Landfill protection methods will likely become stronger in the future with more options for leachate and gas recovery. To make landfills more acceptable to neighborhoods, operators will likely establish larger buffer zones, use more green space, and show more sensitivity to landuse compatibility and landscaping. Illegal dumping is a continuing problem. One major reason for illegal dumping is the cost of legally disposing of waste in landfills. In addition, the declining number of landfills, with those remaining often sited at a distance, has led to increased illegal dumping. Illegal dumping endangers human health and the environment because the dump sites become breeding grounds for animal and insect pests, present safety hazards for children, are sources of pollutants, and disrupt wildlife habitats. INCINERATION AND COMBUSTION Incineration and combustion both include heating MSW to very high temperatures. In the past MSW was burned in incinerators primarily to reduce its volume. During the 1980s technology was developed that allowed MSW to be burned for energy recovery. Use of MSW as a fuel is more commonly termed combustion; however, both terms are used interchangeably. The EPA refers to MSW combustion as a waste-to-energy (WTE) process.
In 2003 approximately thirty-three million tons of MSW were incinerated, representing 14% of the total MSW generated that year. (See Figure 6.8.) The EPA estimates that combusting MSW reduces the amount of 86
Nonhazardous Waste
waste by up to 90% in volume and by up to 75% in weight. As of fall 2004 there were eighty-nine WTE facilities operating in the United States generating approximately 2,500 megawatts of power. Figure 6.12 shows a typical WTE system. At this facility, the trucks dump waste into a pit. The waste is moved to the furnace by a crane. The furnace burns the waste at a very high temperature, heating a boiler that produces steam for generating electricity and heat. Ash collects at the bottom of the furnace, where it is later removed and taken to a landfill for disposal. According to the Rubber Manufacturers Association, 104 million scrap tires were burned as fuel during 2003 in specialized facilities. As shown in Table 6.7, tires have a very high average heat content compared to typical MSW. Some experts think that incinerators are the best alternatives to landfills, while others believe that they are good additions to landfills. WTE facilities do provide an alternative energy source to traditional fossil fuels, and the sale of the energy they produce helps offset the cost of operating the facilities. Incinerators are very expensive to build. According to the Department of Energy (DOE), in 2003 waste-derived energy comprised just over one-half of 1% of the nation’s total energy supply, producing 558 trillion British thermal units (BTUs) of power. (See Figure 6.13.) The DOE hopes to increase this value to 2% by the year 2010. The Environment
FIGURE 6.12
Waste combustion plant with pollution control system
Electricity Power plant Turbine
Generator
Steam
Boiler system Scrubber
Crane
Filter Heat
Waste storage pit
Furnace Stack
Ash collection
Shipped to landfill
SOURCE: “Waste Combustion Plant with Pollution Control System,” in Let’s Reduce and Recycle: Curriculum for Solid Waste Management, U.S. Environmental Protection Agency, Washington, DC, 1990
TABLE 6.7
Average heat content of selected biomass fuels Fuel type Agricultural byproducts Black liquor Digester gas Landfill gas Methane Municipal solid waste Paper pellets Peat Railroad ties Sludge waste Sludge wood Solid byproducts Spent sulfite liquor Tires Utility poles Waste alcohol Wood/wood waste
Heat content
Units
8.248 11.758 0.619 0.490 0.841 9.945 13.029 8.000 12.618 7.512 10.071 25.830 12.720 26.865 12.500 3.800 9.961
Million Btu/short ton Million Btu/short ton Million Btu/thousand cubic feet Million Btu/thousand cubic feet Million Btu/thousand cubic feet Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/short ton Million Btu/barrel Million Btu/short ton
“Table B6. Average Heat Content of Selected Biomass Fuels,” in Renewable Energy Trends 2002, U.S. Department of Energy, Energy Information Administration, Washington, DC, August 2003 SOURCE:
The Environment
Incinerator and WTE Emissions Most experts believe that incineration can never serve as a primary method of garbage disposal because it produces (1) residue that must then be transferred to a landfill and (2) poisonous gases, primarily dioxin and mercury, which are increasingly being found to be dangerous. Incineration may, however, be useful to augment landfill and recycling. WTE plants also have these problems. Mercury is largely impossible to screen with pollution-control devices such as scrubbers (an air pollution device that uses a spray of water or reactant to trap pollutants). In the process of burning paints, fluorescent lights, batteries, medical wastes, or electronics, mercury is released as a gaseous vapor that is poisonous to humans and to the environment. Most of the first incinerators built have been retired because they failed to meet subsequent air quality standards. Some analysts are not satisfied that the emissions problems have been solved, especially the problems of burning materials containing Nonhazardous Waste
87
FIGURE 6.13
THE FEDERAL ROLE IN MSW MANAGEMENT The federal government plays a key role in waste management. Its legislation has set landfill standards under the RCRA and incinerator and landfill emission standards under the Clean Air Act.
Energy consumption associated with fuel from waste, 1970–2003 600
Trillion Btus
500 400 300 200 100 0 1965
1970
1975
1980
1985
1990
1995
2000
2005
Note: Waste includes municipal solid waste, landfill gas, sludge waste, tires, agricultural byproducts, and other waste. SOURCE: Adapted from “Table 10.1. Renewable Energy Consumption by Source, Selected Years, 1949–2003,” in Annual Energy Review, 2003, U.S. Department of Energy, Energy Information Administration, Washington, DC, June 27, 2005, http://www.eia.doe.gov/emeu/aer/ pdf/aer.pdf (accessed August 4, 2005)
chlorine, whose molecules, when burned, create dioxin, a known carcinogen. Regulators are also concerned about the acid gases and heavy metals released from WTE plants. Scrubbers reduce but do not eliminate these emissions. Even when the toxic elements are largely removed from emissions, the resulting ash is still toxic and, when put in landfills, can leach into the groundwater. Thus, toxic compounds in incinerator ash are simply removed from one environmental medium to enter another. Toxic compounds still end up in the soil. By law, toxic residue created by burning waste in incinerators must be treated as hazardous waste and must not be dumped in ordinary landfills. As mentioned above, certain metals and other toxic materials can be released in gaseous emissions during MSW combustion (see Figure 6.14), with mercury and dioxins being the contaminants of greatest concern. Dioxin is the common name for a family of several hundred toxic compounds with similar chemical structures and biological characteristics. Dioxins are not deliberately manufactured—they are the unintended by-products of industrial processes that involve chlorine (such as chlorine bleaching of pulp and paper) or processes that burn chlorine with organic matter. WTE facilities are required to use air pollution control equipment to reduce emissions of toxic chemicals. In 2002 the EPA reported that emissions of organic, metal, and acid gases from sixty-six large MSW incinerators were reduced by more than 90% between 1990 and 2000. Mercury emissions were reduced by 95.1%, while emissions of dioxins were reduced by more than 99%. 88
Nonhazardous Waste
Some waste management laws have been controversial, resulting in legal challenges. Consequently, the federal government has also had an effect on waste management programs through federal court rulings. In a series of rulings, including Supreme Court decisions such as 1992’s Chemical Waste Management Inc. v. Hunt, federal courts have held that shipments of waste are protected under the interstate commerce clause of the U.S. Constitution. As a result, state and local governments may not prohibit landfills from accepting waste from other states, nor may they impose fees on waste disposal that discriminate on the basis of origin. Flow Control Laws Municipalities nationwide have upgraded waste management programs and attempted to deal with public concern over waste issues. In most areas of the country state and local governments have played the lead role in transforming solid waste management. Private waste management firms have also been involved, often under contract or franchise agreements with local governments. Private firms manage most of the commercial waste and increasingly collect residential waste.
Flow control laws require private waste collectors to dispose of their waste in specific landfills. State and/ or local governments institute these laws to guarantee that any new landfill they build will be used. That way, when they sell bonds to get the money to build a new landfill, the bond purchasers will not worry that they will not be repaid. Since 1980 more than $10 billion in municipal bonds have been issued to pay for the construction of solid waste facilities. In many of those cases flow control authority was used to guarantee the investment. Flow control also benefits recycling plants where recycling is financed by fees collected at incinerators or landfills. In the process, however, a monopoly is created, prohibiting facilities outside a jurisdiction from offering competitive services. As a result, there have been a number of court challenges to flow control laws. In 1994 the Supreme Court, in C & A Carbone v. Clarkstown (511 U.S. 383), held that flow control violates the interstate commerce clause. In response, however, many local governments have strongly pushed for the restoration of flow control authority. They have appealed to Congress, with its authority to regulate interstate commerce, to restore the use of flow control. As of summer 2005, bills proposed to address flow control have failed. The Environment
FIGURE 6.14
Waste combustion process Stable gases (carbon dioxide, water vapor, monoxide, nitrogen oxide, hydrogen chloride, and chlorine) Fly ash (particulate matter, carbon, salts, and metals)
Air pollution control device
Atoms combine with oxygen to form stable gases
Combustion chamber Gases pass through flame and break down into atoms
Waste is converted to gases
Waste Bottom ash (carbon, salts, and metals)
“Figure III-23. The Combustion Process,” in RCRA Orientation Manual, EPA530-R-02-016, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, January 2003
SOURCE:
The Environment
Nonhazardous Waste
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CHAPTER 7
NONHAZARDOUS MATERIALS RECOVERY—RECYCLING AND COMPOSTING
Materials recovery is considered one of the most promising ways to reduce the amount of nonhazardous waste requiring disposal. The terms ‘‘recovery’’ and ‘‘recycling’’ are often used interchangeably. Both mean that a waste material is being reused rather than landfilled or incinerated. In general, reuse as a fuel does not fall under the definition of recovery, while composting does. Recycling involves the sorting, collecting, and processing of wastes such as paper, glass, plastic, and metals, which are then refashioned or incorporated into new marketable products. Composting is the decomposition of organic wastes, such as food scraps and yard trimmings, in a manner that produces a humus-like substance for fertilizer or mulch. Recovery reduces environmental degradation and chemicals that pollute water resources, generates jobs and small-scale enterprise, reduces dependence on foreign imports of metals, and conserves water. Some analysts claim that more than half of consumer waste could be economically recycled. However, recycling sometimes requires more energy and water consumption than waste disposal. It depends on how far the materials must be transported and what is necessary to ‘‘clean’’ them before they can be reused. Demand for some recyclable materials is weak, making them economically unfeasible to recycle in a marketdriven society. Municipal solid waste (MSW) recovery offers many advantages. It conserves energy otherwise used to incinerate the waste; reduces the amount of landfill space needed for disposal of waste; reduces possible environmental pollution due to waste disposal; generates jobs and small-scale enterprises; reduces dependence on foreign imports of raw materials; and replaces some chemical fertilizers with composting material, which further lessens possible environmental pollution. The Environment
Many Americans view waste recovery primarily as a way to help the environment. For example, if paper is recycled, fewer trees have to be cut down to make paper. State and local governments see recycling as a way to save money on waste disposal costs and prolong the life of landfill space. Thus, MSW recovery has both environmental and economic components. MATERIAL RECOVERY RATES The Environmental Protection Agency (EPA) publication Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003 (http://www.epa.gov/epaoswer/non-hw/muncpl/ pubs/msw05rpt.pdf, April 2005) reports that Americans recycled 72.3 million tons of MSW in 2003, accounting for 30.6% of total MSW generated. (See Figure 7.1.) This was an average recycling rate of just more than one pound per person per day. Recycling rates for various materials are shown in Table 7.1. The materials with the highest recovery rates were nonferrous metals excluding aluminum (66.7%), yard trimmings (56.3%), and paper and paperboard (48.1%). By contrast, recovery rates were very low for food wastes (2.7%) and plastics (5.2%).
As shown in Table 6.4 in Chapter 6, total materials recovery has increased dramatically over the past few decades. In 1960 the recovery rate was only 6.4%. By 1995 more than a quarter of MSW generated was recovered. The largest gains were achieved during the 1980s and early 1990s. The recovery rate reached 29.4% in 2000, but has increased only slightly since then. The EPA does not break down recovery rates by state. However, the journal BioCycle estimated state by state recycling rates in 2002 in ‘‘The State of Garbage in America ’’ (Scott M. Kaufman, Nora Goldstein, Karsten Millrath, and Nickolas J. Themelis, January 2004). According to the article, the states with the highest recycling rates in 2002 were Maine and Oregon 91
(both with 49%), Minnesota (46%), Iowa (42%), and California (40%).
FIGURE 7.1
Municipal solid waste recycling rates, 1960–2003
Percent recycling
70.0
50.0%
60.0
Percent of generation recycled
Total MSW recycling (million tons)
Total MSW recycling
40.0%
50.0 40.0
30.0%
30.0
20.0%
20.0 10.0%
10.0 0.0
0.0% 1960 1970 1980 1990 1995 2000 2001 2002 2003
“Figure 2. MSW Recycling Rates from 1960 to 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/ muncpl/pubs/msw05rpt.pdf (accessed August 4, 2005) SOURCE:
TABLE 7.1
Municipal solid waste materials generated and recovered by weight, 2003 [In millions of tons and percent of generation of each material]
Paper and paperboard Glass Metals Steel Aluminum Other nonferrous metalsa Total metals Plastics Rubber and leather Textiles Wood Other materials Total materials in products Other wastes Food, otherb Yard trimmings Miscellaneous inorganic wastes Total other wastes Total municipal solid waste
Weight generated
Weight recovered
Recovery as a percent of generation
83.1 12.5
40.0 2.35
48.1% 18.8%
14.0 3.23 1.59
5.09 0.69 1.06
36.4% 21.4% 66.7%
18.8
6.84
36.3%
26.7 6.82 10.6 13.6 4.32
1.39 1.10 1.52 1.28 0.98
5.2% 16.1% 14.4% 9.4% 22.7%
176.4
55.4
31.4%
27.6 28.6
0.75 16.1
2.7% 56.3%
3.62
Neg.
Neg.
59.8
16.9
28.2%
236.2
72.3
30.6%
Notes: Includes waste from residential, commercial, and institutional sources. Details may not add to totals due to rounding. Neg.⫽Less than 5,000 tons or 0.05 percent. a Includes lead from lead-acid batteries. b Includes recovery of other MSW organics for composting. SOURCE: “Table 4. Generation and Recovery of Materials in MSW, 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/msw05rpt.pdf (accessed August 4, 2005)
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Nonhazardous Materials Recovery—Recycling and Composting
Paper The paper industry has been at the leading edge of the recycling revolution. Used paper-based products can be ‘‘de-inked’’ in chemical baths and reduced to a fibrous slurry that can be reformulated into new paper products. Paper can undergo this process several times before the fibers become too damaged for reuse. Paper products vary greatly in the type (hardwood versus softwood) and length of fibers that are used to make them. Recycled papers must typically be sorted into particular usage categories (for example, newsprint or fine writing papers) before being reprocessed. Recycled paper is slightly more costly to produce than ‘‘virgin’’ paper.
Figure 7.2 shows EPA estimates of the tons of paper (and paperboard) products generated as MSW and the tons recovered between 1960 and 2003. Overall the recovery rate for the year 2003 was 48.1%. However, examination of detailed data shows that there were wide variations in rates for specific paper products. For example, the EPA states that newspaper had a recovery rate of 82%. This was the highest rate for any product within the category. Recovery rates were also high for corrugated boxes (71%) and office papers (56%). Most other paper products had moderate recovery rates falling within the 10–40% range. By contrast, paper products such as tissue papers and towels and paper plates and cups had negligible recovery rates (less than 0.05%; http://www.epa. gov/epaoswer/non-hw/muncpl/pubs/msw05rpt.pdf ). Glass Waste glass can be melted down and formed into new glass products over and over without losing its structural integrity. Virgin raw materials, such as sand, limestone, and soda ash are added as needed to formulate new glass products. However, colored glass cannot be easily decolored, as paper is de-inked. This means that glass products must be sorted by color prior to reprocessing.
Figure 7.3 shows EPA estimates of the tons of glass products generated as MSW and the tons recovered between 1960 and 2003. Most glass that becomes MSW is from bottles and jars manufactured for food and drink products. Glass generation rates generally declined between 1980 and 2003 due to competition from the plastics industry for these markets. Glass recovery increased throughout the 1980s and early 1990s and then began declining. Metals Metal recycling is as old as metalworking. Coins and jewelry made of gold and silver were melted down in ancient times to make new coins with images of the latest The Environment
FIGURE 7.2
FIGURE 7.4
Metals generated and recovered, 1960–2003
Paper generated and recovered, 1960–2003
Recovery
Generation
100
20
90
18
80
16
70
14 Million tons
Million tons
Generation
60 50 40
12 10 8 6
30
4
20
2
10
0
0 1960
1965
1970
1975
1980
1985
1990
1995
2000 2003
SOURCE: “Figure 3. Paper Generation and Recovery, 1960 to 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: 2003 Data Tables, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/ 03data.pdf (accessed August 4, 2005)
1960
1965
1970
1975
1980
1985
1990
1995
2000 2003
“Figure 7. Metals Generation and Recovery, 1960 to 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: 2003 Data Tables, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/ 03data.pdf (accessed August 4, 2005) SOURCE:
general, metals must be sorted by composition prior to reprocessing.
FIGURE 7.3
Figure 7.4 shows EPA estimates of the tons of metal products generated as MSW and the tons recovered between 1960 and 2003. According to the EPA, ferrous metals (iron and steel) comprise the largest category of metals in MSW. They are primarily used in durable goods such as appliances, furniture, and tires. Aluminum is used extensively in drink and food cans and packaging materials. Lead, zinc, and copper fall under the category ‘‘other nonferrous metals.’’ They are found in batteries, appliances, and consumer electronics (http://www.epa. gov/epaoswer/non-hw/muncpl/pubs/msw05rpt.pdf ).
Glass generated and recovered, 1960–2003
Generation
Recovery
16 14 12 Million tons
Recovery
10 8 6 4 2 0 1960
1965
1970
1975
1980
1985
1990
1995
2000 2003
“Figure 5. Glass Generation and Recovery, 1960 to 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: 2003 Data Tables, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/ 03data.pdf (accessed August 4, 2005) SOURCE:
ruler. Metal objects were generally considered valuable and were frequently sold or given away, rarely simply discarded. When metal objects could not be repaired, they could be melted down and fashioned into something else. This practice continues in modern society. In The Environment
Metals recovery was relatively flat until the mid1980s, when it began increasing dramatically. Recovery leveled off during the late 1990s. Detailed EPA data show that recovery rates differ greatly from metal to metal. Nearly 67% of nonferrous metals (excluding aluminum) in the 2003 MSW stream were recovered, compared with only 36% of ferrous metals (iron and steel) and 21% of aluminum. The Aluminum Association reports that more than 50% of the aluminum cans produced in the United States are recycled each year. During 2004, fifty-four billion cans were recycled. Plastics Plastic products are manufactured from chemical resins molded into various shapes. There are dozens of Nonhazardous Materials Recovery—Recycling and Composting
93
total of seventy-five million tons of packaging and containers were generated that year. Therefore, one of the major ways to reduce the amount of MSW is to reduce the amount of packaging used for products or to use materials that recycle or biodegrade easily.
FIGURE 7.5
Plastics generated and recovered, 1960–2003
Million tons
Generation
28 26 24 22 20 18 16 14 12 10 8 6 4 2 0 1960
Recovery
An example of source reduction in packaging is compact discs (CDs) and cassettes. Until recently CDs and cassettes were sold in packages far larger than needed. Many customers and recording artists complained to the manufacturers, who now put CDs and cassettes in smaller packages. Many other industries are also using less plastic and paper to package their products.
1965
1970
1975
1980
1985
1990
1995
2000 2003
“Figure 9. Plastics Generation and Recovery, 1960 to 2003,” in Municipal Solid Waste Generation, Recycling, and Disposal in the United States: 2003 Data Tables, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, April 2005, http://www.epa.gov/epaoswer/non-hw/muncpl/pubs/ 03data.pdf (accessed August 4, 2005) SOURCE:
different resins in common use, each with a different chemical formulation. Although waste plastic products can be melted down and reformulated into new products, sorting by resin type must first be performed. Figure 7.5 shows EPA estimates of the tons of plastic products generated as MSW and the tons recovered between 1960 and 2003. In 1960 there were virtually no plastic products in MSW. In 2003 MSW contained nearly twenty-seven million tons of plastic products. This massive increase in generation was accompanied by incredibly low rates of recovery. Only 5.2% of all plastic products generated in MSW during 2003 were recovered. This is less than 1.4 tons of plastic recovered. The plastics recovery rate has hovered around 5% since 1995. Detailed EPA data show that recovery of some plastic products is much higher than others. In 2003 nearly 32% of HDPE milk and water bottles were recovered. HDPE is a plastic resin known as high-density polyethylene. Just over 25% of PET soft drink bottles were recovered from MSW. PET stands for polyethylene terephthalate, another plastic resin. However, recovery rates for other plastic products were very low. The EPA reported a zero recovery rate for plastic plates and cups, trash bags, and similar nondurable goods.
The EPA reported that nearly 39% of packaging and containers were recovered in 2003, up slightly from 38% in 2000. The packaging and container recovery rate was only 10.5% in 1960. The 2003 recovery figures for packaging and containers included 22% of glass, 61% of steel, 36% of aluminum, 56% of paper and paperboard, 9% of plastics, and 15% of wood. RECYCLING PROGRAMS The successful recycling of any product within MSW is dependent on the success of three key components in the recycling process:
• Collection and sorting of the products to be recycled • Processing and manufacturing technologies to convert waste materials into new products • Consumer demand for recycled products and those containing recycled materials Lack of any one of these components seriously jeopardizes recovery efforts for a particular material within the MSW stream. These three factors are represented by the three arrows in the international symbols used to show that a product is recyclable or contains recycled materials. Collection and Sorting Before recyclable materials can be refashioned into new products, they must be collected. Most residential recycling involves curbside collection, drop-off programs, buy-back operations, and/or container deposit systems. In some cases people are required to sort their recyclables prior to collection. Large-scale sorting of recyclable materials is performed at materials recovery facilities (MRFs).
Curbside programs are those in which recyclable items are collected from bins placed outside residences. CURBSIDE PROGRAMS.
Packaging and Containers The EPA’s Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2003 reports that packaging and containers comprise a large proportion of MSW (31.7% in 2003). A 94
Nonhazardous Materials Recovery—Recycling and Composting
According to the journal BioCycle, only 1,042 curbside programs were operating in the United States in 1988. By 2000 this number climbed to 9,709, but then The Environment
dropped to 8,875 by 2002. However, the population served by curbside programs between 2000 and 2002 experienced only a tiny decrease. This probably means that some neighboring programs consolidated to serve wider areas. BioCycle estimates that nearly one hundred and forty million people were served by curbside programs during 2002. States with high levels of curbside service include Connecticut, New York, and New Jersey.
TABLE 7.2
Drop-off centers typically collect residential waste, although some accept commercial waste. They are found in grocery stores, charitable organizations, city-sponsored sites, and apartment complexes. The types of materials accepted vary, although drop-off centers generally accept a greater variety of materials than do curbside collection services. The EPA estimates that more than ten thousand drop-off centers are operated around the United States.
Bottles and cans
DROP-OFF CENTERS.
The largest quantity of recovered materials comes from the commercial sector. Old corrugated containers and office papers are widely collected from businesses. Grocery stores and other retail outlets that use corrugated packaging return large amounts of recovered materials.
Market conditions for materials commonly recycled at malls and shopping centers Material Old corrugated cardboard (OCC) Paper
Plastic film
Food waste Landscaping waste
Construction and Demolition (C&D) waste
COMMERCIAL RECYCLABLES COLLECTION.
In December 2004 the EPA published A Guide to Waste Reduction at Shopping Centers. The booklet provides information about setting up recycling programs for materials commonly found in the MSW of retail stores and other establishments found in shopping centers and malls. Table 7.2 is a list of these materials and indicates the economic strength and stability of the markets for goods produced from the waste materials. Retailers are urged to use the information to decide which materials to include in recycling programs. Buy-Back Centers and Deposit Systems A buy-back center is usually a commercial operation that pays individuals for recovered materials. Examples include scrap metal dealers, paper dealers, waste haulers, and aluminum can centers.
Deposit systems are programs in which consumers pay a deposit on beverage containers at the time of purchase. This deposit can be redeemed if the container is returned empty for reuse. According to the EPA, in early 2005 there were ten states operating deposit programs: Connecticut, Delaware, Hawaii, Iowa, Maine, Massachusetts, Michigan, New York, Oregon, and Vermont. California operates a similar system in which consumers pay a redemption fee. Materials Recovery Facilities Materials recovery facilities (MRFs) sort collected recyclables, process them, and ship them to companies that can use them to produce new or reformulated products. For example, an MRF may sort and crush various The Environment
Fluorescent lamps
Probability of stable market Excellent. High grade—excellent. Mixed paper—good. Glass—good. Plastics—good (for PET and HDPE)*. Aluminum—good. Other metals—good. Depends; market prices can vary widely and are based on the type of film, current commodity prices, and contamination level. Good, depending on the local infrastructure. Good—material can be sold or given away. Consider hosting an event at your mall to distribute compost in the spring. Cement—good. Asphalt—fair. Drywall or gypsum board—fair. Carpet—good. Untreated wood—good. The largest market is boiler fuel. Treated wood should be segregated from untreated wood. For treated wood, contact your local or state solid waste agency for the most appropriate recycling and/or disposal options. Good, although mercury use is decreasing. You must pay to have fluorescent lamps recycled. The typical cost can be up to $1.00 per lamp for very small volumes; prices go down with larger volume recycling.
*PET is polyethylene terephthalate and is primarily used to make soft drink bottles. HDPE is high density polyethylene and is usually used to make milk and water bottles. SOURCE: Adapted from “Appendix A. Materials Commonly Included in Recycling and Waste Prevention Programs at Malls and Shopping Centers,” in A Guide to Waste Reduction at Shopping Centers, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, December 2004, http://www.epa.gov/epaoswer/osw/ conserve/amrguide/amrguide.pdf (accessed August 4, 2005)
types of glass recovered from curbside programs and then ship the processed glass to a bottle factory where it can be used to produce new bottles. MRFs vary widely in the types of materials they accept and the technology and labor they use to sort and process recyclables. Most MRFs are classified as low-technology, meaning that most of the sorting is done manually. High-technology MRFs sort recyclables using eddy currents (swirling air or water), magnetic pulleys, optical sensors, and air classifiers. Newspaper is the major paper commodity processed at MRFs, along with corrugated boxes, used telephone books, magazines, and mixed waste paper. Non-paper commingled recyclables consist of aluminum beverage containers, food cans, glass food and beverage containers, and certain plastics. Most MRFs have separate processing lines for paper and commingled container streams. The type of processing equipment found in a particular plant depends upon the markets for which the processed recyclables are destined and the distances they must be transported. Nonhazardous Materials Recovery—Recycling and Composting
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TABLE 7.3
EPA’s recommended recovered fiber content for paper products
Item
Postconsumer recovered fiber
Notes
Total recovered fiber
Printing and writing papers Reprographic Offset Tablet Envelope
Cotton fiber
Business papers such as bond, electrostatic, copy, mimeo, duplicator, and reproduction Used for book publishing, commercial printing direct mail, technical documents, and manuals Office paper such as note pads and notebooks Wove kraft, white, and colored (including manilla) kraft, unbleached excludes custom envelopes High-quality papers used for stationary, invitations, currency, ledgers, maps, and other specialty items
30%
30%
30% 30% 30% 10–20% 10%
30% 30% 30% 10–20% 10%
30%
30%
Groundwood paper used in newspapers
20–85%
20–100%
Used in rolls or sheets Used rolls or sheets
20–60% 40–60%
20–100% 40–100%
Used for packaging and shipping a variety of goods (⬍300 psi) (⬍300 psi)
25–50% 25–30%
25–50% 25–30%
Newsprint Newsprint Commercial sanitary tissue products Bathroom tissue Paper towels Paperboard and packaging products Corrugated containers
SOURCE: Adapted from “EPA’s Recommended Content Levels for Paper Products,” in 2004 CPG Comprehensive Procurement Guidelines: Buy-Recycled Series: Paper Products, U.S. Environmental Protection Agency, Washington, DC, May 2004, http://www.epa.gov/epaoswer/non-hw/procure/pdf/paper.pdf (accessed August 4, 2005)
The Role of Government
The oldest recycling law in the United States is the Oregon Recycling Opportunity Act, which was passed in 1983 and went into effect in 1986. The Act established curbside residential recycling opportunities in large cities and set up drop-off depots in small towns and rural areas. A growing number of states require that many consumer goods sold must be made from recycled products. In addition, many states have set recycling/recovery goals for their MSW. In 1989 the state of Maine adopted a goal to achieve 50% recycling by the year 1994. Although the deadline was later extended, the state has not been able to achieve it as of 2005. Officials blame the dramatic population growth in southern Maine that boosted the MSW generation rate. For recycling programs to work, there must be markets for recycled products. To help create demand, some states require that newspaper publishers use a minimum proportion of recycled paper. Many states require that recycled materials be used in making products such as telephone directories, trash bags, glass, and plastic containers. All states have some kind of ‘‘buy recycled’’ program that requires them to purchase recycled products when possible. The states also use other incentives for recycling. Most states have introduced curbside collection or public drop-off sites for recyclables. Some states provide financial assistance, incentive money, or tax credits or exemp96
Nonhazardous Materials Recovery—Recycling and Composting
tions for recycling businesses. And almost all states bar certain recyclable materials (such as car and boat batteries, grass cuttings, tires, used motor oil, glass, plastic containers, and newspapers) from entering their landfills. The federal government also helps create a market for recycled goods. The Resource Conservation and Recovery Act (RCRA) requires federal procuring agencies to purchase recycled-content products designated by the EPA in its overall Comprehensive Procurement Guidelines (CPG). The first CPG was issued in May 1995 and included twenty-four designated items. The most recent CPG update was published in April 2004. Requirements for selected paper products are shown in Table 7.3. EPA guidance regarding the purchase of recycled-content products is also included in Recovered Materials Advisory Notices (RMANs). RMANs are published periodically and include recommended recycledcontent ranges for CPG products that are commercially available. In 1995 Congress passed the National Highway System Designation Act. This legislation repealed federal requirements that up to 20% of the asphalt pavement used in federal highway projects had to contain rubbermodified asphalt made from scrap tires or other recovered materials. The original mandate was part of the Intermodal Surface Transportation Efficiency Act of 1991. The purpose was to encourage reuse of scrap tires. According to the Rubber Pavement Association (RPA), the mandate was repealed due to cost and performance The Environment
problems. Rubber-containing asphalt turned out to be more expensive to produce than conventional asphalt. To make matters worse, some road applications failed to provide good results. The goal of repealing the requirements was to enable federal transportation officials to focus on the most useful and cost-effective ways of achieving important safety aims and to increase states’ discretion to implement their highway programs in ways best suited to their own circumstances. In 1996 Congress passed the Mercury-Containing and Rechargeable Battery Management Act (known as the ‘‘battery recycling bill’’). This law phased out the use of mercury in batteries and provided for efficient and cost-effective collection and recycling or proper disposal of used nickel cadmium batteries, small sealed lead-acid batteries, and certain other batteries. It also exempted certain battery collection and recycling programs from some hazardous waste requirements. COMPOSTING
According to the EPA, food and yard waste comprises 25% of the total MSW generated in one year. All plant-based materials in these categories can be recycled by means of composting. The substances most commonly composted are grass cuttings, garden clippings, leaves, and coffee grounds, but well-chopped plant-based food wastes are suitable as well. Using meat-based food scraps is usually discouraged because they are likely to attract animals. To prepare a compost heap or pile, plant wastes are layered with manure or soil to speed decomposition (decay). Approximately every six inches of plant material is layered with about an inch of soil. Watering the mixture and aerating it (turning it) also speeds decomposition. The compost should decay for five to seven months before it is used. Gardeners mix compost with the soil to loosen the structure of the soil and provide it with nutrients, or spread it on top of the soil as a mulch to keep in moisture. Since compost adds nutrients to the soil, slows soil erosion, and improves water retention, it is an alternative to the use of chemical fertilizers. Compost created on a large scale is often used in landscaping, land reclamation, and landfill cover, and to provide high-nutrient soil for farms and nurseries. Yard waste is especially suitable for composting due to its high moisture content. Over the past few decades, composting yard trimmings has become an accepted waste management method in many U.S. locations. The practice got a huge boost beginning in the late 1980s when many states banned yard trimmings from disposal facilities. The 2000 BioCycle report revealed that in 2001 The Environment
there were 3,846 public yard trimming composting sites in the United States. THE HISTORY AND CURRENT STRENGTH OF RECYCLING Recycling has become a major part of MSW management in the United States, and it will likely continue to grow, although at a slower pace than in the past. Recycling, however, did not enjoy immediate success. It started out as a ‘‘do-good’’ activity but eventually became a necessity for municipal governments.
For a quarter-century after the first Earth Day (April 22, 1970), recycling advocates pleaded their case to skeptical decision-makers in the interest of environmental benefit. In the early years of recycling, the economy was unable to use all the plastic, paper, and other materials that were recovered. Many private recycling companies were not able to make a profit. Instead of earning money from recycling, the programs cost them money. Some cities even started dumping their recycled materials into landfills because they could not sell them. Many city leaders felt that money spent on recycling should be used in other areas instead, such as education. Critics of recycling pointed to the problems that recycling was experiencing as evidence that recycling programs could not work. But supporters of recycling suspected that recycling problems stemmed from the success of collection programs, which recouped more than manufacturers were initially able to handle. Advocates of recycling programs had underestimated the wellspring of support for recycling that existed among the American people. In fact, by the mid-1990s, that support translated into marketing success. Recycling had become a revenue-producer, and prices for nearly all recyclables skyrocketed. Cities that were once paying to get rid of waste could earn millions from selling the same material. Recycling programs began to prosper. Theft of recyclables became commonplace. And private industry began to consider recycling as a way to cut expenses and even to add income, rather than as a nuisance that increased overhead costs. The new economics of recycling made it increasingly attractive to many city waste administrators. As with any business, recycling is subject to the cyclical highs and lows of supply and demand. In the early 2000s, the recycling boom leveled off, and prices dropped. At the same time municipal governments faced serious economic problems. In 2002 the newly elected mayor of New York City halted most of the city’s recycling programs to save money. In 2004 the programs were reinstated after the city signed a long-term contract with a recycling firm. Nonhazardous Materials Recovery—Recycling and Composting
97
There are several barriers, however, that continue to hinder the development of the recycling market: • Consumers are often unaware of recycled products. • Consumers often lack confidence in the quality of recycled products. • The transportation costs of carrying recyclables to processing plants are high. • Questions about supply and demand deter investors. • It is difficult to recover or sort certain materials, such as oil, tires, and plastics. • Recycled products are generally more expensive. Some analysts believe that recycling rates for MSW have reached a plateau and cannot easily be increased due to the supply and demand imbalance in recycledcontent markets. They prefer to focus on source reduction, that is, the reduction of the amount of MSW produced in the first place. One method for reducing MSW generation is a principle called Extended Producer Responsibility (EPR). EPR regulations require manufacturers and producers to take some responsibility for the final disposition of their products. This provides an incentive for products and their packaging to be more recoverable and contain less toxic materials. EPR is a cornerstone of recycling requirements in Canada, Japan, and the European Union. SCRAP TIRE RECYCLING—A SUCCESS STORY Scrap tires have always posed a disposal problem for the United States. Scrap tires accumulated in landfills or uncontrolled tire dumps can pose health and fire hazards. The tires are highly combustible, do not compost, and do not degrade easily. The material, primarily hydrocarbons, burns easily, producing toxic, bad-smelling air pollutants and toxic runoff when burned in the open. Health effects that can result from exposure to an open tire fire include irritation of the skin, eyes, and mucous membranes; respiratory effects; central nervous system depression; and cancer. (The controlled combustion of scrap tires in special incinerators does not produce these toxic emissions.) Scrap tires do not compress in landfills and provide breeding grounds for a variety of pests. In fact, some states ban the disposal of tires in landfills.
Prior to the 1980s scrap tires were either landfilled, illegally dumped, or stockpiled. In 1985 Minnesota passed the first state legislation dealing with scrap tires. Other states followed suit. Several waste management companies invested in tire-to-fuel projects, and by 1990 up to twenty-five million scrap tires per year were burned for fuel. During the 1990s new markets emerged for shredded rubber from scrap tires in civil engineering applications (for example, road building and landfill cover). 98
Nonhazardous Materials Recovery—Recycling and Composting
The Rubber Manufacturers Association (RMA) is a trade organization based in Washington, D.C., that collects and reports data on scrap tires. In July 2004 the RMA published U.S. Scrap Tire Markets—2003 Edition. The RMA estimates that 290 million scrap tires were generated in the United States in 2003. As shown in Figure 7.6, this rate has gradually increased since 1990. Just over 80% of the scrap tires generated in 2003 were recycled or recovered in some way. This value has increased dramatically since 1990, when only 24.5% of scrap tires were reused. (See Figure 7.6.) Figure 7.7 shows the disposition of scrap tires in 2003. Nearly half (44.7%) were used as a fuel source to generate power. A tiny percentage (0.2%) was burned in electric arc furnaces to produce high-carbon steel. Another 9.3% were landfilled, while 3.1% were exported to other countries. The disposition of approximately 10% of the scrap tires is unknown. The remaining 33% (approximately ninety-six million tires) were recycled in various end-use markets as follows: • Civil engineering (19%)—scrap tires are shredded and reused in a variety of civil engineering and construction applications. The primary uses are as fill material in roads, landfill banks, and septic tank leachate fields. Tire shreds are valued for their light weight and other desirable properties compared with traditional materials used for these purposes. • Ground rubber markets (10%)—the rubber in tires can be ground down to a consistency suitable for use in asphalt and other surfacing materials. Ground rubber provides added durability and cushioning to roads, running tracks, and playground surfaces. It is also used to produce consumer items, such as mulch and landscaping products. • Cut/punched/stamped rubber markets (2%)—the chemical and physical properties of rubber allow it to be cut, punched, and stamped into a variety of products. Typical items include belts, gaskets, seals, and electrical insulation. According to the RMA, there are approximately 275 million scrap tires remaining in stockpiles around the United States as of 2003. More than 90% are located in only eleven states: Alabama, Colorado, Connecticut, Massachusetts, Michigan, New Jersey, New York, Ohio, Pennsylvania, Texas, and Washington. The number of stockpiled scrap tires is down dramatically from 1992, when at least one billion were estimated to exist. FUTURE FOCUS: ELECTRONIC WASTE RECYCLING The disposal of obsolete electronic products, such as computers, cell phones, and televisions, is expected to pose a major problem in the coming decades. The issue is The Environment
FIGURE 7.6
U.S. scrap tires generated and recycled or recovered, 1990–2003
Scrap tires recycled or recovered
Scrap tire generation
% Usage 100
350
90 300 265
253
265
80.4
250 223
67 62.1
200
233.3
60 50
164.5 138.5
100
70
218
177.5
54.7 150
80
77.6
40
% Scrap tire utilization
252
Millions of tires
290
281
30
27 68
20
50 24.5
11
10 0
0 1990
1992
1994
1996
1998
2001
2003
“Figure 1. U.S. Scrap Tire Markets 1990–2003,” in U.S. Scrap Tire Markets: 2003 Edition, Rubber Manufacturers Association, Washington, DC, July 2004, https://www.rma.org/publications/scrap_tires/index.cfm?PublicationID⫽11302&CFID⫽2451774&CFTOKEN⫽57977325 (accessed August 4, 2005)
SOURCE:
discussed in a July 2001 article by the U.S. Geological Survey (USGS) titled ‘‘Obsolete Computers, Gold Mine or High-Tech Trash?’’ The article notes that a typical personal computer (PC) becomes obsolete in 2–5 years. The USGS estimates that up to twenty million PCs per year become obsolete in the United States. Studies performed in the late 1990s indicated that consumers seldom discarded old computers. Many were kept as a back-up or given away. However, disposal is expected to become more common as new computer sales increase.
FIGURE 7.7
U.S. scrap tire disposition, 2003
Unknown 10.3%
Export 3.1% Landfill 9.3% Electric arc furnaces 0.2%
Miscellaneous/ agriculture 1.7%
Tire derived fuel 44.7% Civil engineering 19.4% Ground rubber 9.7%
Cut/punched stamped 2% SOURCE: “Figure 2. U.S. Scrap Tire Disposition, 2003,” in U.S. Scrap Tire Markets: 2003 Edition, Rubber Manufacturers Association, Washington, DC, July 2004, https://www.rma.org/publications/ scrap_tires/index.cfm?PublicationID⫽11302&CFID⫽2451774& CFTOKEN⫽57977325 (accessed August 4, 2005)
The Environment
According to the USGS report, approximately 2.6 million personal computers were recycled in the United States in 1998. The agency projected that fifty-five million PCs would be landfilled in 2005 and one-hundredfifty million would be recycled. Figure 7.8 is a materials flow diagram developed by the USGS to show the processes involved in disposal and recycling of obsolete computers and their parts. Computers and other electronic devices contain materials that are valuable for reuse, particularly metals, plastics, and glass. The most common metals in PCs are aluminum, steel, and copper. Small amounts of precious metals, such as gold, palladium, platinum, and silver, are also found in computer circuit boards. Some of the metals used in PCs (antimony, arsenic, cadmium, chromium, Nonhazardous Materials Recovery—Recycling and Composting
99
FIGURE 7.8
What happens to obsolete computers and their components
Obsolete computers in storage Obsolete computers
Donation recipients
Reusable parts and Remanufacturing
refurbished computers
Metals, glass, and mixed plastics
Recycling Nonhazardous Municipal activities waste waste landfill consisting Glass CRT* manufacturers of collection and Separated separation Plastic manufacturers plastics Hazardous Hazardous waste landfill Mixed plastics waste Waste to energy Smelters
*Cathode ray tubes SOURCE: “Figure 2. A Generalized Materials Flow Diagram Illustrating What Happens to Obsolete PCs and Their Components,” in Obsolete Computers,“Gold Mine,” or High-Tech Trash? Resource Recovery from Recycling, U.S. Department of the Interior, U.S. Geological Survey, Reston, VA, July 2001, http://pubs.usgs.gov/fs/fs060-01/ fs060-01.pdf (accessed August 4, 2005)
cobalt, lead, mercury, and selenium) are classified as hazardous by the Resource Conservation and Recovery Act and cannot be disposed of in municipal solid waste landfills. The primary source of plastics is the computer casing. Plastic can be melted down to produce new materials or used as a fuel in certain industrial processes. Most of
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Nonhazardous Materials Recovery—Recycling and Composting
the glass content of computers is in cathode ray tube (CRT) monitors. This glass contains lead, which is a hazardous material. However, the glass can be reused to produce new CRTs. According to the USGS, more than fifty-two thousand metric tons of steel, glass, plastic, and other materials were recovered by United States electronics recyclers in 1998 (the latest year for which data are available). In 2003 the state of California passed legislation called the Electronic Waste Recycling Act. This act requires electronic manufacturers to reduce the amount of hazardous substances used in specific electronic products sold in California. It also established a funding mechanism to ensure that these products are properly collected and recycled at the end of their useful lives. In 2005 retailers began collecting fees from consumers purchasing certain electronic products (primarily CRTs and other display products). The money is turned over to the state and distributed to qualified companies engaged in collecting and recycling the products. According to a July 2005 article in The Mercury News of San Jose, California, the electronics recycling program has been successful so far (Karl Schoenberger, ‘‘E-Waste Recycling Program Hits Stride,’’ July 19, 2005). The article notes that California has garnered $15 million in collected fees from retail outlets. Approximately $6 million of this amount has been distributed to recycling companies. Although there have been complaints about the amount of paperwork involved in the recycling process, in general, the program is considered to be running well across the country. In 2004 California passed a similar recycling bill that applies to cell phones. It goes into effect in July 2006.
The Environment
CHAPTER 8
HAZARDOUS AND RADIOACTIVE WASTE
The most toxic and dangerous waste materials produced in the United States are those classified by the government as hazardous or radioactive.
WHAT IS HAZARDOUS WASTE?
Hazardous waste is dangerous solid waste. The U.S. government’s definition of solid waste includes materials we would ordinarily consider ‘‘solid,’’ as well as sludges, semi-solids, liquids, and even containers of gases. The vast majority of hazardous waste is generated by industrial sources. Small amounts come from commercial and residential sources. Officially, hazardous waste is defined as a waste that is either listed as such in the U.S. Environmental Protection Agency (EPA) regulations or exhibits one or more of the following characteristics: corrosivity, ignitability, reactivity, or contains toxic constituents in excess of federal standards. (See Figure 8.1.) In 2005 the EPA had a list of more than five hundred hazardous wastes. Because of its dangerous characteristics, hazardous waste requires special care when being stored, transported, or discarded. Most hazardous wastes are regulated under Subtitle C of the Resource Conservation and Recovery Act (RCRA). The EPA has the primary responsibility for permitting facilities that treat, store, and dispose of hazardous waste. The states can adopt more stringent regulations if they wish. Contamination of the air, water, and soil with hazardous waste can frequently lead to serious health problems. Exposure to some hazardous wastes is believed to cause cancer, degenerative diseases, mental retardation, birth defects, and chromosomal changes. While most scientists agree that exposure to high doses of hazardous waste is dangerous, there is less agreement on the danger of exposure to low doses. The Environment
INDUSTRIAL HAZARDOUS WASTE Industrial hazardous wastes are usually a combination of compounds, one or more of which may be hazardous. For example, used pickling solution from a metal processor may contain acid, a hazardous waste, along with water and other nonhazardous compounds. (Pickling is a chemical method of cleaning metal and removing rust during processing.) A mixture of wastes produced regularly as a result of industrial processes generally consists of diluted rather than full-strength compounds. Often the hazardous components are suspended or dissolved in a mixture of dirt, oil, or water.
Every two years the EPA, in partnership with the states, publishes The National Biennial RCRA Hazardous Waste Report. The latest report available was published in 2005 and includes data from 2003 (http://www.epa. ov/epaoswer/hazwaste/data/br03/national03.pdf ). The EPA distinguishes between large-quantity generators and small-quantity generators of hazardous waste. A large-quantity generator is one that: • generates at least one thousand kilograms (2,200 pounds) of RCRA hazardous waste in any single month, • generates in any single month or accumulates at any time at least one kilogram (2.2 pounds) of RCRA acute hazardous waste, or • generates or accumulates at any time at least one hundred kilograms (220 pounds) of spill cleanup material contaminated with RCRA acute hazardous waste. In 2003 there were 15,584 large-quantity generators and 2,110 small-quantity generators. Together they generated 30.2 million tons of RCRA hazardous waste. The five states with the largest generation of hazardous waste were Texas (6.6 million tons), Louisiana (4.6 million tons), Kentucky (2.4 million tons), Mississippi (2.0 million tons), 101
FIGURE 8.1
Types of hazardous waste
• Corrosive—A corrosive material can wear away (corrode) or destroy a substance. For example, most acids are corrosives that can eat through metal, burn skin on contact, and give off vapors that burn the eyes.
• Ignitable—An ignitable material can burst into flames easily. It poses a fire hazard; can irritate the skin, eyes, and lungs; and may give off harmful vapors. Gasoline, paint, and furniture polish are ignitable.
• Reactive—A reactive material can explode or create poisonous gas when combined with other chemicals. For example, chlorine bleach and ammonia are reactive and create a poisonous gas when they come into contact with each other.
• Toxic—Toxic materials or substances can poison people and other life. Toxic substances can cause illness and even death if swallowed or absorbed through the skin. Pesticides, weed killers, and many household cleaners are toxic.
“What Kinds of Hazardous Waste Are There?” in Fast Flash I: Hazardous Substances and Hazardous Waste, U.S. Environmental Protection Agency, Washington, DC, undated, http://www.epa.gov/ superfund/students/clas_act/haz-ed/ff_01.htm (accessed August 4, 2005) SOURCE:
and Ohio (1.8 million tons). Together, these states accounted for nearly 58% of the total quantity generated. The chemical industry was by far the largest producer, responsible for fourteen million tons of hazardous waste, or 46% of the total. Petroleum and coal products manufacturers were responsible for 3.9 million tons (13% of the total), followed by the waste treatment and disposal industry with 1.9 million tons (6% of the total). HAZARDOUS WASTE FROM SMALL BUSINESSES AND HOUSEHOLDS A small percentage of hazardous waste comes from thousands of small-quantity generators—businesses that produce less than one thousand kilograms of hazardous waste per month. Table 8.1 shows a list of typical smallquantity generators and the types of hazardous waste they produce. Hazardous wastes from small-quantity generators and households are regulated under Subtitle D of RCRA.
Household hazardous waste (HHW) includes solvents, paints, cleaners, stains, varnishes, pesticides, motor oil, and car batteries. (See Table 8.2.) The EPA reports that Americans generate 1.6 million tons of household hazar102
Hazardous and Radioactive Waste
dous waste every year. The average home can have as much as one hundred pounds of these wastes in basements, garages, and storage buildings. Because of the relatively low amount of hazardous substances in individual products, HHW is not regulated as a hazardous waste. Since the 1980s many communities have held special collection days for household hazardous waste to ensure that it is disposed of properly. More than three thousand such programs have been held in the United States. METHODS OF MANAGING HAZARDOUS WASTE Prior to the 1970s most industrial hazardous waste was dumped in landfills, stored on-site, burned, or discharged to surface waters with little or no treatment. Since the Pollution Prevention Act of 1990, industrial waste management follows a hierarchy introduced by the EPA. (See Figure 8.2.) Source reduction is the preferred method for waste management. This is an activity that prevents the generation of waste initially—for example, a change in operating practices or raw materials. The second choice is recycling, followed by energy recovery. If none of these methods is feasible, then treatment prior to disposal is recommended.
For example, a paper mill that changes its pulping chemicals might reduce the amount of toxic liquid left over after the paper is produced. If that is not possible, perhaps the pulping liquid could be recycled and reused in the process. If not, perhaps the liquid can be burned for fuel to recover energy. If not, and the liquid requires disposal, it should be treated as necessary to reduce its toxicity before being released into the environment. A variety of techniques exist for safely managing hazardous wastes, including: • Reduction—Waste generators change their manufacturing processes and materials in order to produce less hazardous waste. For example, a food packaging plant might replace solvent-based adhesives, which result in hazardous waste, with water-based adhesives, which result in nonhazardous waste. • Recycling—Some waste materials become raw material for another process or can be recovered, reused, or sold. • Treatment—A variety of chemical, biological, and thermal processes can be applied to neutralize or destroy toxic compounds in hazardous waste. (See Table 8.3.) For example, microorganisms or chemicals can remove hazardous hydrocarbons from contaminated water. • Land disposal—State and federal regulations require the pre-treatment of most hazardous wastes before they can be discarded in landfills. These treated materials can only be placed in specially designed land disposal facilities. The Environment
TABLE 8.1
Typical hazardous waste generated by small businesses Type of business
How generated
Typical wastes
Drycleaning and laundry plants
Commercial drycleaning processes
Furniture/wood manufacturing and refinishing
Wood cleaning and wax removal, refinishing/stripping, staining, painting, finishing, brush cleaning and spray brush cleaning Paint preparation and painting, carpentry and floor work, other specialty contracting activities, heavy construction, wrecking and demolition, vehicle and equipment maintenance for construction activities Diagnostic and other laboratory testing
Construction
Laboratories Vehicle maintenance
Printing and allied industries Equipment repair
Pesticide end-users/application services Educational and vocational shops Photo processing Leather manufacturing
Degreasing, rust removal, paint preparation, spray booth, spray guns, brush cleaning, paint removal, tank cleanout, installing lead-acid batteries, oil and fluid replacement Plate preparation, stencil preparation for screen printing, photoprocessing, printing, cleanup Degreasing, equipment cleaning, rust removal, paint preparation, painting, paint removal, spray booth, spray guns, and brush cleaning. Pesticide application and cleanup
Automobile engine and body repair, metalworking, graphic arts-plate preparation, woodworking Processing and developing negatives/prints, stabilization system cleaning Hair removal, bating, soaking, tanning, buffing, and dyeing
Still residues from solvent distillation, spent filter cartridges, cooked powder residue, spent solvents, unused perchloroethylene Ignitable wastes, toxic wastes, solvent wastes, paint wastes
Ignitable wastes, toxic wastes, solvent wastes, paint wastes, used oil, acids/bases
Spent solvents, unused reagents, reaction products, testing samples, contaminated materials Acids/bases, solvents, ignitable wastes, toxic wastes, paint wastes, batteries, used oil, unused cleaning chemicals Acids/bases, heavy metal wastes, solvents, toxic wastes, ink, unused chemicals Acids/bases, toxic wastes, ignitable wastes, paint wastes, solvents
Used/unused pesticides, solvent wastes, ignitable wastes, contaminated soil (from spills), contaminated rinsewater, empty containers Ignitable wastes, solvent wastes, acids/bases, paint wastes Acid regenerants, cleaners, ignitable wastes, silver Acids/bases, ignitables wastes, toxic wastes, solvent wastes, unused chemicals
SOURCE: Adapted from “Typical Hazardous Waste Generated by Small Businesses,” in Managing Your Hazardous Waste, A Guide for Small Businesses, EPA530-K-01-005, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, December 2001
• Injection wells—Hazardous waste may be injected deep underground under high pressure in wells thousands of feet deep. (See Figure 8.3.) • Incineration—Hazardous waste can be burned in incinerators. However, as waste is burned, hot gases are released into the atmosphere, carrying toxic materials not consumed by the flames. In 1999 the Clinton administration imposed a ban on new hazardous waste incinerators. GOVERNMENT REGULATION The Toxics Release Inventory The Toxics Release Inventory (TRI) was established under the Emergency Planning and Community Right-toKnow Act of 1986. Under the program certain industrial facilities using specific toxic chemicals must report annually on their waste management activities and toxic chemical releases. These releases are to air, land, or water. More than 650 toxic chemicals are on the TRI list. In addition, the Pollution Prevention Act of 1990 requires the EPA to collect data on toxic chemicals recycled, treated, or combusted for energy recovery.
Manufacturing facilities (called ‘‘original’’ industries) have had to report under the TRI program since 1987. In 1998 the TRI requirements were extended to a second group of industries called the ‘‘new’’ industries. These include metal and coal mining, electric utilities The Environment
burning coal or oil, chemical wholesale distributors, petroleum terminals, bulk storage facilities, RCRA Subtitle C hazardous water treatment and disposal facilities, solvent recovery services, and federal facilities. However, only facilities with ten or more full-time employees that use certain thresholds of toxic chemicals are included. The 2003 Toxics Release Inventory (TRI) Public Data Release Report was published in May 2005. The report states that 25.8 billion pounds of TRI chemicals were waste managed during 2003. The breakdown by management method is shown in Figure 8.4. Thirty-six percent of the waste was recycled, while 33% was treated. Another 18% was released to the environment, and 13% was used for energy recovery. The EPA reports that 4.44 billion pounds of TRI chemicals were released during 2003 by 23,811 facilities. The vast majority of the chemicals (88%) were released on-site. The remainder was released off-site. Figure 8.5 shows the distribution of releases to the environment. A breakdown by industry is provided in Figure 8.6. The metal mining industry was responsible for more than a quarter of the releases (28%), followed by electric utilities (24%) and primary metals production (11%). The states with the highest releases were Alaska (540 million pounds), Nevada (409 million pounds), Texas (262 million pounds), Ohio (252 million pounds), and Utah (242 million pounds). These five states accounted for nearly 40% of all TRI Hazardous and Radioactive Waste
103
FIGURE 8.2
TABLE 8.2
Common household hazardous wastes Cleaning products
Indoor pesticides
• • • • • • •
• • • • • • •
Oven cleaners Drain cleaners Wood and metal cleaners and polishes Toilet cleaners Tub, tile, shower cleaners Bleach (laundry) Pool chemicals
Ant sprays and baits Cockroach sprays and baits Flea repellents and shampoos Bug sprays Houseplant insecticides Moth repellents Mouse and rat poisons and baits
Automotive products
Workshop/painting supplies
• • • • • • • •
• • • • • • • •
Motor oil Fuel additives Carburetor and fuel injection cleaners Air conditioning refrigerants Starter fluids Automotive batteries Transmission and brake fluid Antifreeze
Adhesives and glues Furniture strippers Oil or enamel based paint Stains and finishes Paint thinners and turpentine Paint strippers and removers Photographic chemicals Fixatives and other solvents
Lawn and garden products
Miscellaneous
• Herbicides • Insecticides • Fungicides/wood preservatives
• • • •
Other flammable products
Waste management hierarchy
Source reduction
Batteries Mercury thermostats or thermometers Fluorescent light bulbs Driveway sealer
Recycling/ reuse
• Propane tanks and other compressed gas cylinders • Kerosene • Home heating oil • Diesel fuel • Gas/oil mix • Lighter fluid
“List of Common HHW Products,” in Municipal Solid Waste, U.S. Environmental Protection Agency, Washington, DC, October 29, 2002, http://www.epa.gov/epaoswer/non-hw/muncpl/hhw-list.htm (accessed August 4, 2005)
If no
If no
Treatment
Disposal
SOURCE:
“Figure 1-2. Waste Management Hierarchy,” in 1999 Toxics Release Inventory—Public Data Release, U.S. Environmental Protection Agency, Office of Environmental Information, Washington, DC, April 2001 SOURCE:
TABLE 8.3
Technologies to neutralize or destroy toxic compounds in hazardous waste Technology Biodegradation Chemical reduction Combustion Deactivation Macroencapsulation Neutralization Precipitation Recovery of metals Recovery of organics Stabilization
Description Biodegradation uses microorganisms to breakdown organic compounds to make a wasteless toxic. Chemical reduction converts metal and inorganic constituents in wastewater into insoluble precipitates that are later settled out of the wastewater, leaving a lower concentration of metaIs and inorganics in the wastewater. Combustion destroys organic wastes or makes them less hazardous through burning in boilers, industrial furnaces, or incinerators. Deactivation is treatment of a waste to remove the characteristic of ignitability, corrosivity, or reactivity. Macroencapsulation is the application of a surface coating material to seal hazardous constituents in place and prevent them from leaching or escaping. Neutralization makes certain wastes less acidic or certain substances less alkaline. Precipitation removes metal and inorganic solids from liquid wastes to allow the safe disposal of the hazardous solid portion. Recovery of organics uses direct physical removal methods to extract metal or inorganic constituents from a waste. Recovery of organics uses direct physical removal methods (e.g., distillation, steam stripping) to extract organic constituents from a waste. Stabilization (also referred to as solidification) involves the addition of stabilizing agents (e.g., Portland cement) to a waste to reduce the leachability of metal constituents.
Adapted from “Figure III-21. Excerpts from the 40 CFR 268.42 Technology-Based Standards Table,” in RCRA Orientation Manual, EPA530-R-02016, U.S. Environmental Protection Agency, Office of Solid Waste and Emergency Response, Washington, DC, January 2003 SOURCE:
releases in 2003. According to the EPA, releases of TRI chemicals declined by 59% between 1988 and 2003. The Resource Conservation and Recovery Act The Resource Conservation and Recovery Act (RCRA), first enacted by Congress in 1976 and expanded by amendments in 1980, 1984, 1992, and 1996, was 104
Hazardous and Radioactive Waste
designed to manage the disposal, incineration, treatment, and storage of waste in landfills, surface impoundments, waste piles, tanks, and container storage areas. It regulates the production and disposal of hazardous waste, and provides guidelines and mandates to improve waste disposal practices. The EPA also has the authority under the RCRA to require businesses with hazardous waste The Environment
FIGURE 8.3
FIGURE 8.4
Typical class I injection well T
Management methods for hazardous wastes included in Toxic Release Inventory, 2003 [25.8 billion pounds managed]
Monitoring of injection pressure and flow rate ensures peak efficiency and regulatory compliance. Energy recovery 13% Double barriers of concrete and steel protect drinking water aquifers.
Recycled 36%
Released 18% A pressurized “annulus” fluid is monitored continuously to detect possible leaks.
Drinking water aquifer Treated 33%
Protective concrete (grout seal) and steel barriers continue to the injection zone.
Poorly permeable rock
Laterally extensive, poorly permeable confining layer retards upward flow of wastes.
SOURCE: Adapted from