40 Part 81 promulgated by the U.S. Environmental Protection Agency. The area of the polygon in square coverage units. The length of the polygon perimeter of the polygon in coverage units. The software-assigned unique integer identification number. A user-assigned identification number.
Federal area particulates classification descriptor.
Effective date of 40 CFR Part 81 classification. Federal area particulates attainment designation. The following are subjective comments regarding this data. In some cases classification areas are based on Hydrologic Units whose boundaries conflict with county boundaries and air basin boundaries. Where there was conflict, the air basin boundary was taken as the 'correct' line.