Class I Area 1 : A specifically designated area where the degradation of air quality is stringently restricted (e.g., many national parks, wilderness areas). See: prevention of significant deterioration
National Environmental Policy Act (NEPA), Glossary of Terms Used in DOE NEPA Documents, US Department of Energy, Office of NEPA Policy and Compliance, USA 1998. http://energy.gov/sites/prod/files/NEPA_Glossary%2 008_2011.pdf, (EHS - Amer) {515}