1、 https:/crsreports.congress.gov November 2, 2016Protecting Clean Air in National Parks and Wilderness AreasIn 1977, major amendments to the Clean Air Act (CAA) included provisions for the prevention of significant deterioration (PSD) of air quality. The PSD provisions were enacted for several purpos
2、es, including to preserve, protect, and enhance the air quality in national parks, national wilderness areas, national monuments, national seashores, and other areas of special national or regional natural, recreational, scenic, or historic value; and to insure that economic growth will occur in a m
3、anner consistent with the preservation of existing clean air resources. Two significant aspects of the PSD provisions relate to federal lands and federal land managers: the classification of areas for air quality protection and management, and the role of federal land managers in maintaining and imp
4、roving air quality under the CAA. Classification of Areas The PSD provisions establish classifications of air quality (42 U.S.C. 7472). Class I areas are those with the highest air quality and whose air quality is most stringently protected. Class II includes all other areas, unless they are designa