On August 16, 1974, the Environmental Protection Agency announced its latest proposed regulations¹ for implementation of the Clean Air Act's stated purpose, ". . . to protect and enhance the quality of the Nation's air resources . . ."² Usually referred to as "significant deterioration" regulations, the proposed regulations are EPA's latest move in a chess game against the Sierra Club, whose opening move, Sierra Club v. Ruckelshaus³ in 1972, was the legal equivalent to taking the EPA queen. EPA has skillfully used the bureaucratic riposte of delay and attrition, once resorting to the famed Nixon Defense (king's pawn to knight's fore: "In EPA's view, there has been no definitive judicial resolution of the issue whether the Clean Air Act requires prevention of significant deterioration of air quality. When the issue was presented to the Supreme Court, the Court was equally divided . . ."⁴). The latest proposed regulations are very weak, and the Sierra Club must now decide if it will settle for a stalemate.

The term "significant deterioration" refers to the degradation of existing air quality in areas of the nation, where it is now better than is required by EPA's secondary standards for pollutant concentrations in ambient air. According to the Sierra Club ruling, such degradation is forbidden by the "protect and enhance" language of the Clean Air Act, and the EPA Administrator has a nondiscretionary duty under the statute to disapprove all state implementation plans that do not contain provisions to prevent it. The proposed regulations represent the Administrator's latest attempt to establish rules governing the preparation and approval of these significant deterioration portions of state plans.