Another explosion, this time near Detroit:

DETROIT (WWJ) – BREAKING – There has been an explosion at the Marathon Detroit Refinery and a mandatory evacuation order is in effect for the area just off of Schafer from Ropp down to Dix and all the way down to Outer Drive per Melvindale police.

Reports of the explosion came in from several listeners to WWJ Newsradio 950 just before 6 p.m. and it appears that one of the tankers on the site may have exploded.

Marathon Detroit Refinery told WWJ that they were trying to get the situation under control but could not comment further.

The controversial site is a major destination for tar sands oil, and is in Michigan's single most polluted zip code:

More recently, residents have been concerned about huge black piles appearing along the Detroit River. They're made up of a material known as petroleum coke, or petcoke, that originates from the Marathon facility and is being sold to a company called Koch Minerals LLC.

Marathon said that since they do not own either the petcoke or the property where the mounds of the petcoke were dumped, they are not responsible for moving it.

The Michigan Department of Environmental Quality (DEQ) conducted tests on the petcoke, following concerns expressed by U.S. Reps. Gary Peters (D-Bloomfield Township) and John Conyers (D-Detroit), but found them not to be hazardous.

Not satisfied with these results, State Rep. Rashida Tlaib (D-Detroit) collected samples for independent testing last month and is now waiting on the results. She's also concerned about the potential for polluted stormwater to flow into the Detroit River, although DEQ Water Resources Division spokesman Andrew Hartz told the Detroit News last week that the piles are being managed to prevent that sort of runoff.

Petcoke may form combustible dust concentrations in air. Is this another case of unregulated industry gone wild? Stay tuned.