MDEQ believes it has solved mystery of foamy substance in Melvindale

White substance leaks onto Schaefer Freeway during rainfall

A mysterious substance returned to Melvindale Monday when storms hit Metro Detroit. (WDIV)

MELVINDALE, Mich. - The Michigan Department of Environmental Quality believes it has solved the mystery behind a white, foamy substance leaking out of the ground in Melvindale.

White substance baffles authorities

The substance appeared for the first time about three weeks ago. Officials found it oozing from the ground on Schaefer Freeway between Oakwood Boulevard and I-75, but they couldn't figure out what it was or determine its origin.

It returned July 31 when severe weather hit Metro Detroit. The substance came out of the ground along Schaefer Freeway near the Marathon refinery, but Marathon officials told police it had nothing to do with the refinery.

"There are no operations at the Marathon refinery that would produce a substance like that in the sewer or coming out of the ground," Marathon officials said in a statement.

"They want the whole road shut down right now until we can figure out exactly what's going on," a Melvindale police officer told Local 4 at the time.

On Monday, heavy rain returned to Metro Detroit, and the white substance oozed onto the freeway once again.

Officials took samples of the substance Monday.

"We've got two independent labs that are going to be testing this product that you see here to my right," Assistant Fire Chief Steven Densmore said. "We have a representative from MDEQ (the Michigan Department of Environmental Quality) here as well, overseeing the operation, as well as Western Wayne Hazmat Team."

MDEQ has possible explanation

MDEQ officials announced Thursday that the substance appears to be formed by surface coating from a parking lot mixing with rain.

Officials are still investigating the substance to make sure this is the cause.

MDEQ officials spoke with the business that owns the parking lot, and steps are being taken to prevent the substance from forming.

As long as the substance stays in the sewer system, it's not harmful, MDEQ officials said.

Testing is ongoing.

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