Power outage at Marathon refinery in Detroit prompts controlled gas burning

Officials are monitoring air quality in and around the Marathon refinery in Detroit after a power outage at the site resulted in a controlled burning of gases, the energy company said Sunday.

Marathon said on its website, "Due to a power outage the operating conditions at Marathon's Detroit refinery have made flaring necessary."

Flares, according to the company, are safety devices that allow for the safe combustion of extra gases under certain conditions. 

Detroit Mayor Mary Sheffield said in a written statement that visible smoke from the flaring had residents concerned.

The Michigan Department of Environment, Great Lakes and Energy and refinery personnel are monitoring air quality both at the site and in surrounding neighborhoods, according to Sheffield. She added that, as of Sunday night, monitoring "has not detected gas readings of concern."

Officials in Melvindale, a city near the refinery, said in a social media post Sunday afternoon that the state agency had identified "a very light sulfur reading," but that there was "nothing to be alarmed about."

Schaefer Road between Interstate 75 and Dix Road is closed as a precaution, Sheffield said.

Marathon's Detroit refinery, located on the city's southwest side, processes crude oils into gasoline, distillates, asphalt, natural gas liquids and petrochemicals, propane and heavy fuel oil, according to the company.