The U.S. Environmental Protection Agency (EPA) finalized a rule on March 28, 2013, to revise its emission limits for hydrogen chloride, filterable particulate matter, sulfur dioxide, lead, selenium, sulfur, and mercury for certain new coal-fired electricity generators. The rule, evidently was prompted by a petition for reconsideration of limits established in 2012 and, according to EPA, allows mercury emissions up to 0.003 pound per gigawatt-hour at plants that do not burn low-rank virgin coal and for integrated combined cycle units. For all new electric generating units (EGUs), the rule revises limits for hydrogen chloride, filterable particulate matter, sulfur dioxide, lead, and selenium.

EPA says that the revised emission limits “incorporate information about the variability of the best performing EGUs and more accurately reflect the capabilities of emission control equipment for new EGUs.” Although it took comment on the emission standards for particulate emissions during startup and shutdown conditions, EPA did not act on those issues, stating that the agency “needs additional time to consider and evaluate the comments and data provided” before it can act on startup and shutdown definitions and limits.