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Clean Air Markets

Basic Information

EPA regulates air pollution from power plants that contributes to environmental problems such as acid rain, ozone and particle pollution. EPA implements regulatory programs to achieve these environmental improvements, including the Acid Rain Program, the Cross-State Air Pollution Rule, and the Mercury and Air Toxics Standards.

To evaluate these programs, EPA monitors emissions from power plants of sulfur dioxide (SO2), nitrogen oxides (NOx), and carbon dioxide (CO2). EPA also monitors and regulates air toxics including mercury, arsenic, hydrochloric acid, and hydrofluoric acid emissions from power plants through the Mercury and Air Toxics Standards.

EPA also monitors air quality and environmental and ecological conditions through its monitoring networks, including the Clean Air Status and Trends Network (CASTNET) and the Long Term Monitoring (LTM) network. This monitoring helps assess trends in air and water quality, atmospheric deposition, and ecological effects resulting from changes in air pollution.

Quickly access data through our Data Resources page.

Learn more about the results of these programs in the Progress Report.

Browse our Frequent Questions page for answers to common questions.

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