From May 22, 2016 to June 23, 2016, DTE Energy Company, Monroe, Michigan (DTE) exceeded a National Emission Standards for Hazardous Air Pollutants for Coal- and Oil-Fired Electric Utility Steam Generating Units (NESHAP Subpart UUUUU) mercury emission limit at Unit 2, one of its four coal-fired boilers, for 33 days. From August 5, 2016 to August 22, 2016, DTE again exceeded a NESHAP Subpart UUUUU mercury emission limit at Unit 2 for 18 days. The Michigan Department of Environmental Quality communicated these emission exceedances to EPA on February 14, 2017, after determining they were not delegated the authority to enforce NESHAP Subpart UUUUU. EPA will concurrently lodge a Consent Agreement and Final Order (CAFO) and Administrative Complaint Order (ACO).
The ACO requires DTE to install, permit, and maintain a calcium bromide injection system and mercury process monitors at each coal-fired boiler to prevent mercury emission exceedances, and addresses the violations set forth in the Finding of Violation issued to DTE on September 29, 2017. The CAFO requires DTE to pay a civil penalty of $120,000 to resolve these violations.
EPA received a waiver from the Department of Justice on February 28, 2018.