On January *, 2020, Region 5 filed a Consent Decree (CD) settling a judicial civil action under Section 113(b) of the Clean Air Act with Dynegy Zimmer LLC's (parent company Vistra Energy, William H. Zimmer Generating Station (Zimmer Station) in Moscow, Ohio.
In 2008, 2010, and 2014 EPA issued Notice and Finding of Violations (NOVs/FOVs) to the Zimmer Station alleging that the facility exceeded a SO2 Best Available Control Technology and an opacity limitation contained in OAC Chapter 3745-17-07(A)(1) of the Ohio SIP, NSPS Subpart Da, and Prevention of Significant Deterioration (PSD) and Title V Permits. EPA estimates that Dynegy Zimmer?s Clean Air Act non-compliance resulted in over 520 tons per year of excess sulfuric acid mist emissions (causing the opacity exceedances) and 134 tons per year of excess sulfur dioxide emissions.
The CD will require that Dynegy Zimmer meet enforceable sulfuric acid mist emission limits to ensure compliance with opacity limitations and continuously comply with existing SO2, opacity, and particulate matter limitations. To comply with the CD, Dynegy Zimmer upgraded its sulfuric acid mist mitigation system in 2014 and has increased regent injection rates to ensure adequate and continuous removal of sulfuric acid. The CD also requires that Dynegy conduct root cause failure analyses (RCFAs) if SO2 emissions exceed certain trigger levels which are set below the permitted emission rates. As part of these RCFAs, Dynegy Zimmer is, among other