Temporary Stay On Parts Of MASTS Rule

US Environmental Protection Agency (EPA )has published a “partial stay” in the August 2 Federal Register, which puts a temporary halt on the national new source emissions standards for hazardous air pollutants from coal- and oil-fired electric utility steam generating units. Certain emissions limits to mercury and air toxics under the Clean Air Act have been placed on hold until November 2, 2012.

EPA issued the National Emissions Standards for Hazardous Air Pollutants (NESHAPS) for the source category, generally referred to as the mercury and air toxic standards (MATS Rules), on February 16, 2012. On July 20, the Agency issued a letter stating its intent to review the rule and grant petitions for reconsideration on certain new source issues related to the emissions standards, including measurement issues related to mercury, particulate matter, and hydrochloric acid.

The specific parts of the MATS Rule that have been placed on hold include 40 CFR 63.9984(a), 63.10005(g), 63.10030(c), Table 1 to Subpart UUUUU of 40 CFR Part 63, and row 2 of Table 3 to Subpart UUUUU of 40 CFR Part 63. The action also stays the effectiveness of any monitoring, recordkeeping, and reporting requirements related to new source standards. The rest of the rule, however, remains in effect.


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