Clean Air Act (1963, 1970, 1990)

views updated

Clean Air Act (1963, 1970, 1990)

The 1970 Clean Air Act and major amendments to the act in 1977 and 1990 serve as the backbone of efforts to control air pollution in the United States. This law established one of the most complex regulatory programs in the country. Efforts to control air pollution in the United States date back to 1881, when Chicago and Cincinnati passed laws to control industrial smoke and soot. Other municipalities followed suit and the momentum continued to build. In 1952, Oregon became the first state to adopt a significant program to control air pollution, and three years later, the federal government became involved for the first time, when the Air Pollution Control Act was passed. This law provided funds to assist the states in their air pollution control activities.

In 1963, the first Clean Air Act was passed. The act provided permanent federal aid for research, support for the development of state pollution control agencies, and federal involvement in cross-boundary air pollution cases. An amendment to the act in 1965 directed the Department of Health, Education and Welfare (HEW) to establish federal emission standards for motor vehicles. (At this time, HEW administered air pollution laws. The Environmental Protection Agency (EPA) was not created until 1970.) This represented a significant move by the federal government from a supportive to an active role in setting air pollution policy. The 1967 Air Quality Act provided additional funding to the states, required them to establish Air Quality Control Regions, and directed HEW to obtain and make available information on the health effects of air pollutants and to identify pollution control techniques.

The Clean Air Act of 1970 marked a dramatic change in air pollution policy in the United States. Following enactment of this law, the federal government, not the states, would be the focal point for air pollution policy. This act established the framework that continues to be the foundation for air pollution control policy today. The impetus for this change was the belief that the state-based approach was not working and increased pressure from a developing environmental consciousness across the country. Public sentiment was growing so significantly that environmental issues demanded the attention of high-ranking officials. In fact, the leading policy entrepreneurs on the issue were President Richard Nixon and Senator Edmund Muskie of Maine.

The regulatory framework of The Clean Air Act featured four key components. First, National Ambient Air Quality Standards (NAAQSs) were established for six major pollutants: carbon monoxide , lead (in 1977), nitrogen dioxide, ground-level ozone (a key component of smog ), particulate matter, and sulfur dioxide . For each of these pollutants, sometimes referred to as criteria pollutants, primary and secondary standards were set. The primary standards were designed to protect human health; the secondary standards were based on protecting crops, forests, and buildings if the primary standards were not capable of doing so. The Act stipulated that these standards must apply to the entire country and be set by the EPA, based on the best available scientific information. The costs of attaining these standards were not among the factors considered. The EPA was also directed to set standards for less common toxic air pollutants.

Second, New Source Performance Standards (NSPSs) would be set by the EPA. These standards would determine how much air pollution would be allowed by new plants in various industrial sectors. The standards were to be based on the best available control technology (BACT) and best available retrofit technology (BART) available for the control of pollutants at sources such as power plants , steel factories, and chemical plants.

Third, mobile source emission standards were established to control automobile emissions . These standards were specified in the statute (rather than left to the EPA), and schedules for meeting them were also written into the law. It was thought that such an approach was crucial to ensure success with the powerful auto industry. The pollutants regulated were carbon monoxide, hydrocarbons , and nitrogen oxides , with goals of reducing the first two pollutants by 90% and nitrogen oxides by 82% by 1975.

The final component of the air protection act dealt with the implementation of the new air quality standards. Each state would be encouraged to devise a state implementation plan (SIP), specifying how the state would meet the national standards. These plans had to be approved by the EPA; if a state did not have an approved SIP, the EPA would administer the Clean Air Act in that state. However, since the federal government was in charge of establishing pollution standards for new mobile and stationary sources, even the states with an SIP had limited flexibility. The main focal point for the states was the control of existing stationary sources, and if necessary, mobile sources. The states had to set limits in their SIPs that allowed them to achieve the NAAQSs by a statutorily determined deadline. One problem with this approach was the construction of tall smokestacks, which helped move pollution out of a particular airshed but did not reduce overall pollution levels. The states were also charged with monitoring and enforcing the Clean Air Act.

The 1977 amendments to the Clean Air Act dealt with three main issues: nonattainment, auto emissions, and the prevention of air quality deterioration in areas where the air was already relatively clean. The first two issues were resolved primarily by delaying deadlines and increasing penalties. Largely in response to a court decision in favor of environmentalists (Sierra Club v. Ruckelshaus, 1972), the 1977 amendments included a program for the prevention of significant deterioration (PSD) of air that was already clean. This program would prevent polluting the air up to the national levels in areas where the air was cleaner than the standards. In Class I areas, areas with near pristine air quality, no new significant air pollution would be allowed. Class I areas are airsheds over large national parks and wilderness areas. In Class II areas, a moderate degree of air quality deterioration would be allowed. And finally, in Class III areas, air deterioration up to the national secondary standards would be allowed. Most of the country that had air cleaner than the NAAQSs was classified as Class II. Related to the prevention of significant deterioration was a provision to protect and enhance visibility in national parks and wilderness areas even if the air pollution was not a threat to human health. The impetus for this section of the bill was the growing visibility problem in parks, especially in the Southwest.

Throughout the 1980s, efforts to further amend the Clean Air Act were stymied. President Ronald Reagan was opposed to any strengthening of the Act, which he argued would hurt the economy. In Congress, the controversy over acid rain between members from the Midwest and the Northeast further contributed to the stalemate. Gridlock on the issue broke with the election of George Bush, who supported amendments to the Act, and the rise of Senator George Mitchell of Maine to Senate Majority Leader. Over the next two years, the issues were hammered out between environmentalists and industry and between different regions of the country. Major players in Congress were Representatives John Dingell of Michigan and Henry Waxman of California and Senators Robert Byrd of West Virginia and Mitchell.

Major amendments to the Clean Air Act were passed in the fall of 1990. These amendments addressed four major topics: (1) acid rain, (2) toxic air pollutants, (3) nonattainment areas, and (4) ozone layer depletion .To address acid rain, the amendments mandated a 10 million ton reduction in annual sulfur dioxide emissions (a 40% reduction based on the 1980 levels) and a two million ton annual reduction in nitrogen oxides to be completed in a two-phase program by the year 2010. Most of this reduction will come from old utility power plants. The law also creates marketable pollution allowances, so that a utility that reduces emissions more than required can sell those pollution rights to another source. Economists argue that, to increase efficiency, such an approach should become more widespread for all pollution control.

Due to the failure of the toxic air pollutant provisions of the 1970 Clean Air Act, new, more stringent provisions were adopted requiring regulations for all major sources of 189 varieties of toxic air pollution within ten years. Areas of the country still in nonattainment for criteria pollutants were given from three to twenty years to meet these standards. These areas were also required to impose tighter controls to meet the standards. To help these areas and other parts of the country, the Act required stiffer motor vehicle emissions standards and cleaner gasoline . Finally, three chemical families that contribute to the destruction of the stratospheric ozone layer (chlorofluorocarbons (CFCs), hydrochloroflurocarbons (HCFCs), and methyl chloroform) were to be phased out of production and use.

In 1997, the EPA issued revised national ambient air quality standards (NAAQS), setting stricter standards for ozone and particulate matter. The American Trucking Association and other state and industry groups legally challenged the new standards on the grounds that the EPA did not have the authority under the Act to make such changes. On February 27, 2001, the U.S. Supreme Court unanimously upheld the constitutionality of the Clean Air Act as interpreted by the EPA, and all remaining legal challenges to other aspects of the standards change were rejected by a Washington DC District Court ruling in early 2002.

The Clean Air Act has met with mixed success. The national average pollutant levels for the criteria pollutants have decreased. Nevertheless, many localities have not achieved these standards and are in perpetual nonattainment. Not surprisingly, major urban areas are those most frequently in nonattainment. The pollutant for which standards are most often exceeded is ozone, or smog. This is due in part to increases in nitrogen oxides (NOx), which disperse ozone. NOx emissions increased by approximately 20% between 1970 and 2000. As a result, some parts of the country have had worsening ozone levels. According to the EPA, the average ozone levels in 29 national parks increased by over 4% between 1990 and 2000.

The greatest successes of air pollution control have come with lead, which between 1981 and 2000 was reduced by 93% (largely due to the phasing-out of leaded gasoline), and particulates, which were reduced by 47% in the same period. Overall particulate emissions were down 88% since 1970. Carbon monoxide has dropped by 25% and volatile organic compounds and sulfur dioxides have declined by over 40% each between 1970 and 2000. However, air quality analysis is complex, and it is important to note that some changes may be due to shifts in the economy, changes in weather patterns, or other such variables rather than directly attributable to the Clean Air Act.

In February 2002, President Bush introduced the "Clear Skies" legislation, an initiative that, if fully adopted, would make some significant changes to the Clean Air Act. Among them would be a weakening or elimination of new source review regulations and BART rules, and a new "cap and trade" plan that would allow power plants that produced excessive toxic emissions to 'buy credits' from other plants who had levels under the standards. The Bush administration hailed the initiative as a less expensive way to accelerate air pollution clean-up and a more economy-friendly alternative to the Kyoto Protocol for greenhouse gas reductions, while environmental groups and other critics called it a roll-back of the Clean Air Act progress.

[Christopher McGrory Klyza and Paula Anne Ford-Martin ]



Belden, Roy S. The Clean Air Act. Washington, DC: ABA Publishing, 2001.

Dewey, Scott Hamilton. Don't Breathe the Air: Air Pollution and U.S. Environmental Politics, 19451970. College Station, TX: Texas A&M University Press, 2000.

Erbes, Russell E. A Practical Guide to Air Quality Compliance. New York: John Wiley & Sons, 1996.

U.S. Government Printing Office and R. A. Leiter. Legislative History of the Clean Air Act Amendments of 1990. Buffalo, NY: William s Hein & Co, 1998.


Adams, Rebecca. " Hill Demands Clean Air Act Rewrite Data." CQ Weekly. 60, no.18 (May 4 2002): 1161 (2).


Department of Energy, Energy Information Administration. Emissions of Greenhouse Gases in the United States: 2000. Report #DOE/EIA-0573(2000): December 2001. Full-text available online at

Environmental Protection Agency (EPA). AIRNow

Environmental Protection Agency (EPA), Office of Air and Radiation. Latest Findings on National Air Quality: 2000 Status and Trends [Accessed June 5, 2002.]