On December 1, 2014, the U.S. Environmental Protection Agency (EPA) released a pre-publication proposed action reconsidering aspects of its Major-Source Boiler Maximum Available Control Technology (MACT) (40 C.F.R. 63, Subpart DDDDD), and proposing additional amendments and technical corrections. The major-source reconsideration addresses: (1) the definitions of startup and shutdown periods and the work practices that apply during such periods, (2) revisions to carbon monoxide (CO) limits based on a minimum CO level of 130 parts per million (ppm), and (3) the use of particulate matter (PM) continuous parameter monitoring system, including the consequences of exceeding the operating parameter. The proposal also deletes the rule language providing an affirmative defense for malfunction, in light of recent case law vacating similar affirmative defense provisions in the Portland Cement MACT. See NRDC v. EPA, 749 F.3d 1055 (D.C. Cir. 2014). The proposed technical corrections address inadvertent errors included in the final rule, related to definitions, references, applicability, and compliance. Notably, EPA is proposing to exclude electric generating units (EGU) covered by 40 C.F.R. 63, subpart UUUUU, and natural gas-fired EGUs (as defined in subpart UUUUU) that fire at least 90 percent natural gas on an annual heat input basis.
EPA has also released a separate pre-publication proposed action reconsidering certain aspects of its Area-Source Boiler MACT (40 C.F.R. 63, Subpart JJJJJJ), and proposing additional amendments and technical corrections. The area-source reconsideration addresses: (1) the definitions of startup and shutdown periods, (2) alternative PM standards for new oil-fired boilers that combust low-sulfur oil, (3) establishment of a subcategory for limited-use boilers and the applicable standards for that subcategory, (4) provisions that eliminate further performance testing for PM for certain boilers, and (5) provisions that eliminate fuel sampling at certain coal-fired boilers. The area-source proposal also deletes the rule language providing an affirmative defense for malfunction, and includes several technical corrections.
Comments on both proposals are due 45 days after publication in the Federal Register, which should occur in the next several weeks.
For additional information, contact Andrew Holway.