On 2/02/2019, Marathon Refinery reported a release greater than 100 pounds of Hydrogen Sulfide and greater than 500 pounds of Sulfur Dioxide to the NRC (Reports #1236607 and 1236625) from a main stack due to unknown causes. Marathon activated their emergency response crews and began conducting air monitoring in and around the facility and identified a leak in their propane processing facilities. On 2/03/2019, Marathon began receiving odor complaints from facility staff and surrounding neighborhoods and notified NRC (Report #1236651). MDEQ and the City of Detroit are aware of the situation, and the City requested USEPA’s assistance with air monitoring.
Update: Marathon reported greater than 100 pounds of Hydrogen Sulfide and greater than 500 pounds of Sulfur Dioxide which are the Reportable Quantity (RQ) thresholds under CERCLA. Marathon is required to fully report the amount released to Michigan DEQ within 30-days.