Environmentalists achieved a major goal in December 1970 with the establishment of the U.S. Environmental Protection Agency (EPA), which brought together in a single agency many federal programs charged with protecting the environment. The EPA sets and enforces tolerable limits of pollution, and it establishes timetables to bring polluters into line with standards; since most of the requirements are of recent origin, industries are given reasonable time, often several years, to conform to standards. The EPA also has the authority to coordinate and support research and anti-pollution efforts of state and local 82

governments, private and public groups, and educational institutions. Regional EPA offices develop, propose, and implement approved regional programs for comprehensive environmental protection activities. Data collected since the agency began its work show significant improvements in environmental quality; there has been a nationwide decline of virtually all air pollutants, for example. However, in 1990 many Americans believed that still greater efforts to combat air pollution were needed. Congress passed important amendments to the Clean Air Act, and they were signed into law by President George Bush (1989-1993). Among other things, the legislation incorporated an innovative market-based system designed to secure a substantial reduction in sulfur dioxide emissions, which produce what is known as acid rain. This type of pollution is believed to cause serious damage to forests and lakes, particularly in the eastern part of the United States and Canada.