Mercury Limits for Cement Plants

摘要

In response to several court decisions that reinforced the meaning of a maximum achievable control technology (MACT) "floor" for control of hazardous air pollu-tants (HAPs), EPA has stepped forward with new amendments restricting emissions of HAPs from the nation's 100 or so Portland cement manu-facturing plants. The rule is notable for the first-time establishment of mercury emis-sions limits for existing cement kilns.rnAccording to a 2007 federal circuit court opinion, a MACT floor must reflect the average emissions limitation achieved by the best performing 12 percent of existing sources. The court indicated that in prior rulemaking, EPA had issued regulations for cement kilns, which the Agency con-sidered achievable by all sources. Under that approach, EPA did not establish limits for total hydrocarbons (THCs) for existing sources and nongreenfield new sources, nor for hydrochloric acid (HC1) or mercury for new or existing sources.