The emissions squeeze: environmental regulations keep getting tighter

摘要

When Congress amended the Clean Air Act in 1977 to reduce power plant emissions, it exempted existing power plants. At that time it was assumed that over a few years these plants would be retired and replaced with less polluting plants. The Act did, however, include a New Source Review (NSR) provision. Under this provision, new power plants and older power plants that made major modifications were required to install modern pollution controls. Unfortunately, the definition of what constitutes major modifications is open to interpretation. In early 2003 the U.S. Environmental Protection Agency's (EPA) proposed NSR reform program became effective. The changes included.