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The Effects of Title IV of the Clean Air Act Amendments of 1990 on Electric Utilities: An Update

Release date: March 1997

The Clean Air Act Amendments of 1990 address numerous air quality problems in the United States were not entirely covered in earlier legislation. One of these problems is acid rain caused by sulfur dioxide (SO2 ) and nitrogen oxides (NOx ) emissions from fossil-fueled electric power plants and, to a lesser extent, from other industrial and transportation sources.

Title IV of the Act created a two-phased plan, administered by the U.S. Environmental Protection Agency (EPA), to reduce acid rain in the United States. Phase I runs from 1995 through 1999, and Phase II, which is more stringent than Phase I, begins in 2000. Title IV contains a table listing 261 generating units that are required to comply with Phase I. They are generally referred to by EPA as Table 1 units. Most of these units are coal fired with relatively high emissions. An additional 174 units are participating in Phase I based on the rules established by EPA, allowing a utility to designate substitution or compensating units as part of their Phase I compliance plans. Therefore, 435 units are now considered Phase I units. More than 2,000 units will be affected by Phase II.

This report updates and expands a report published by the Energy Information Administration in 1994 titled, Electric Utility Phase I Acid Rain Compliance Strategies for the Clean Air Act Amendments of 1990; it describes the strategies used to comply with the Acid Rain Program in 1995, the effect of compliance on SO emissions levels, the cost of compliance, and the effects of the program on coal supply and demand.

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