Clean Air Act of 1970

Introduction

The Clean Air Act of 1970 is a U.S. federal law designed to improve the air quality in the United States. The primary goal of the Clean Air Act is ensuring public health, but the act has a secondary effect of improving the environment by regulating the production of some greenhouse gases.

The first Clean Air Act was passed in 1963, and the act has been amended several times. The 1970 amendments to the Clean Air Act were a major milestone, however, because the 1970 amendments marked the first time that Congress established national environmental standards and enforcement mechanisms. In 1970, Congress also established the Environmental Protection Agency (EPA), largely to implement and administer the Clean Air Act of 1970.

Historical Background and Scientific Foundations

Although the Clean Air Act of 1970 provided the first national air pollution controls, some American cities enacted air pollution regulations in the nineteenth century. In 1881, Chicago and Cincinnati passed air control measures to reduce smog. Other American cities and states followed suit and began to regulate air pollution on a local level.

Two events in the mid-twentieth century highlighted the need for stronger air quality controls. In 1948, a thick layer of smog settled over the small town of Donora, Pennsylvania. The cloud remained for five days, killing 20 people and sickening nearly half of the city’s citizens. In London, England, the Great Smog of December 1952 killed nearly 4,000 people over four days; an additional 8,000 people died over the following months from respiratory problems that had been worsened by the smog.

In 1955, Congress passed the Air Pollution Control Act (APCA), the first federal air pollution legislation. The Air Pollution Control Act of 1955 only provided federal funds for research to determine the scope and sources of air contaminants. Although the APCA did not regulate the production of air contaminants, it did demonstrate that the federal government had taken an interest in air pollution.

The Clean Air Act of 1963 was the first federal law that addressed the issue of air pollution control. The Clean Air Act of 1963 authorized the U.S. Public Health Service to research ways to monitor and control air pollution. The absence of an enforcement mechanism, however, limited the effectiveness of the Clean Air Act of 1963.

The Air Quality Act of 1967 (AQA) was the first federal act that allowed for some enforcement of air quality regulations. The AQA authorized the Secretary of Health, Education, and Welfare to designate “air quality regions,” areas with high levels of interstate air pollution, throughout the United States. The AQA then permitted state governments to adopt and enforce air quality standards within the various air quality regions. The AQA was largely viewed as a failure. By 1970, the federal government had designated only a few dozen air quality regions, instead of the 100 or more designated regions that had been anticipated. Also, no state had developed a full air pollution control program.

The failure of the Air Quality Act highlighted the need for nationwide regulation and federal enforcement standards. Congress passed the Clean Air Act (CAA) of 1970 to address these shortfalls. The Clean Air Act of 1970 also sought to avoid the relative inaction that occurred under the Air Quality Act by establishing deadlines for meeting the air quality standards set forth in the Clean Air Act.

The Clean Air Act of 1970 mandated the development of comprehensive federal and state air quality regulations that would reduce emissions from both industrial sources and automobiles. The CAA established several regulatory programs to monitor pollution sources and enforce the provisions of the CAA, including the National Ambient Air Quality Standards, New Source Performance Standards, and National Emission Standards for Hazardous Air Pollutants. Although various government regulatory agencies are responsible for enforcing the Clean Air Act, the CAA was the first major environmental law that allowed citizens to the sue any corporation or government that fails to comply with the CAA.

The Clean Air Act charged the newly formed Environmental Protection Agency with enforcing the air pollution standards set forth in the act. The CAA contains a provision that allows individual states to control the enforcement of the CAA within their territory if they elect to do so. A state may submit a State Implementation Plan (SIP) to the EPA. The SIP must meet the minimum requirements set forth in the CAA.

Impact and Issues

Although the Clean Air Act of 1970 was an ambitious law, it was only the beginning of a national legislative effort to improve air quality and the environment. The CAA of 1970 was amended in 1977 and underwent a substantial revision in 1990. The Clean Air Act Amendments of 1977 (CAAA of 1977) contained two major parts. First, the CAAA of 1977 contained provisions for the Prevention of Significant Deterioration (PSD). The PSD sought to maintain good air quality in areas that had seen positive results under the National Ambient Air Quality Standards (NAAQS). Second, the CAAA of 1977 modified air pollution controls for areas that had not attained the goals set forth under the NAAQS by establishing permit review requirements for industry.

The Clean Air Act Amendments of 1990 (CAAA of 1990) further strengthened existing air pollution controls and addressed new environment issues that scientific research had revealed. The CAAA of 1990 strengthened federal control over air pollution, but still allowed states to enforce the act within their boundaries.

The CAAA of 1990 strengthened automobile emission standards and set a timetable for reductions. The CAAA of 1990 also promoted the use of low-sulfur and alternative fuels in automobiles as a means of reducing sulfur dioxide (SO₂). Research conducted during the 1970s and 1980s indicated that SO₂ was one of the primary contributing factors to acid rain.

The CAAA of 1990 also mandated a reduction in chlorofluorocarbons (CFCs). In the 1980s, the scientific community and the public became increasingly concerned about the depletion of the ozone layer by CFCs.

WORDS TO KNOW

ACID RAIN: A form of precipitation that is significantly more acidic than neutral water, often produced as the result of industrial processes.

AIR POLLUTION: The existence in the air of substances in concentrations that are determined unacceptable. Contaminants in the air we breathe come mainly from manufacturing industries, electric power plants, automobiles, buses, and trucks.

ENVIRONMENTAL PROTECTION AGENCY: An agency of the United States government since 1970, charged with protecting human health and the environment through research, regulation, and education.

GREENHOUSE GASES: Gases whose accumulation in the atmosphere increase heat retention.

SMOG: A mixture of smoke or other atmospheric pollutants combined with fog.

Since 1970, the Clean Air Act and its amendments have been remarkably effective at reducing air pollution in the United States. Under the Clean Air Act, the EPA has set national air quality standards for six airborne pollutants: carbon monoxide (CO), ozone (O₃), lead (Pb), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and particulate matter.

Since 1970, the airborne concentration of these six pollutants has decreased by more than 50%. EPA studies show that industrial source air pollution has decreased by nearly 70% since 1970, and new cars are 90% cleaner today than in 1970.

Since the Clean Air Act only addresses air pollutants that affect the health and welfare of citizens, the EPA did not include carbon dioxide (CO₂) as a pollutant that is regulated under the CAA. Although carbon dioxide is one of the major greenhouse gases, carbon dioxide occurs in the natural environment and is generally safe to breathe. In 2007, the U.S. Supreme Court ruled in Massachusetts v. EPA that carbon dioxide and other greenhouses gases are pollutants. The court ordered the EPA to review its policy of not regulating greenhouse gases under the Clean Air Act.

Primary Source Connection

The first Clean Air Act was passed in 1963. It set standards for emissions of air pollutants by power plants and steel mills. Amendments to the act were passed in 1966, 1967, and 1969. These regulations set standards for moving sources of emissions, like cars, trucks, and trains, and established research grants for improving fuel efficiency.

By 1970 Congress realized that the Clean Air Act required major revision. The Clean Air Act of 1970 established much stricter emission controls than its predecessor. It was an extremely ambitious act and industries were economically challenged to comply with its standards. This act was revised throughout the 1970s, extending deadlines and rewriting standards.

After two decades, Congress again revisited the Clean Air Act. In 1990 it underwent a major revision, strengthening standards and improving regulations. The act contains six subchapters. The first deals with the programs and activities governed by the act. The second sets emission standards for moving sources. The third subchapter discusses general provisions of the act, such as impact assessment, monitoring, and auditing. The fourth and sixth subchapters are concerned with acid rain and stratospheric ozone depletion. The fifth subchapter deals with permitting for large stationary sources of air pollution.

CLEAN AIR ACT

7401. Congressional findings and declaration of purpose

1. Findings
   The Congress finds—
   1. that the predominant part of the Nation’s population is located in its rapidly expanding metropolitan and other urban areas, which generally cross the boundary lines of local jurisdictions and often extend into two or more States;
   2. that the growth in the amount and complexity of air pollution brought about by urbanization, industrial development, and the increasing use of motor vehicles, has resulted in mounting dangers to the public health and welfare, including injury to agricultural crops and livestock, damage to and the deterioration of property, and hazards to air and ground transportation;
   3. that air pollution prevention (that is, the reduction or elimination, through any measures, of the amount of pollutants produced or created at the source) and air pollution control at its source is the primary responsibility of States and local governments; and
   4. that Federal financial assistance and leadership is essential for the development of cooperative Federal, State, regional, and local programs to prevent and control air pollution.
2. Declaration
   The purposes of this subchapter are—
   1. to protect and enhance the quality of the Nation’s air resources so as to promote the public health and welfare and the productive capacity of its population;
   2. to initiate and accelerate a national research and development program to achieve the prevention and control of air pollution;
   3. to provide technical and financial assistance to State and local governments in connection with the development and execution of their air pollution prevention and control programs; and
   4. to encourage and assist the development and operation of regional air pollution prevention and control programs.
3. Pollution prevention
   A primary goal of this chapter is to encourage or otherwise promote reasonable Federal, State, and local governmental actions, consistent with the provisions of this chapter, for pollution prevention.

United States Code

U.S. CODE. “AIR POLLUTION PREVENTION AND CONTROL.” TITLE 42, CHAPTER 85, SUBCHAPTER I, PART A, SECTION 7401.

See Also Acid Rain; Air Pollution; National Oceanic and Atmospheric Administration (NOAA)

BIBLIOGRAPHY

Web Sites

American Meteorological Society. “History of the Clean Air Act: A Guide to Clean Air Legislation Past and Present.” http://www.ametsoc.org/sloan/cleanair/index.html (accessed April 20, 2008).

National Safety Council. “Background on Air Pollution.” March 6, 2006. http://www.nsc.org/EHC/mobile/acback.htm (accessed April 20, 2008).

U.S. Environmental Protection Agency. “Air Trends: Basic Information.” April 8, 2008. http://www.epa.gov/airtrends/sixpoll.html (accessed April 20, 2008).

U.S. Environmental Protection Agency. “The Clean Air Act of 1970.” http://www.epa.gov/history/topics/caa70/11.htm (accessed April 20, 2008).

Joseph P. Hyder