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Clean Air Act

The Clean Air Act of 1970 (as amended) regulates airborne emissions of a variety of pollutants from area, stationary, and mobile sources. The 1990 amendments to this act were intended primarily to fill the gaps in the earlier regulations, such as acid rain, ground level ozone, stratospheric ozone depletion, and air toxins. The amendments identify a list of 189 hazardous air pollutants. The EPA must study these chemicals, identify their sources, determine if emissions standards are warranted, and promulgate appropriate regulations.

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Last Updated: January 04, 2017