DETROIT (WWJ/AP) – Michigan environmental officials are looking into the effect that dust from petroleum coke piles is having along the Detroit River.

Michigan U.S. Rep. Gary Peters said Thursday that the state Department of Environmental Quality has learned dust from the mounds “appear to be an issue during the loading of material onto freighters.”

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Peters has introduced legislation calling for an investigation into any health and environmental risks from the petroleum coke piles in southwest Detroit.

The mounds of what’s known as “pet coke” are a byproduct of oil refining used in energy production. The material has been brought by trucks from the nearby Marathon Petroleum Co. refinery and stored at a site off Jefferson Avenue in southwest Detroit, where it’s loaded onto freighters.

The mounds began drawing more attention starting earlier this year. Area residents, the Canadian government and U.S. lawmakers are among those concerned about potential pollution and health effects.

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Peters and fellow U.S. Rep. John Conyers have asked the Michigan Department of Environmental Quality to investigate whether Detroit Bulk Storage complies with state regulations. 

Peters has said an open drain lets runoff from the piles drain into the Great Lakes watershed during storms.

Tests by the Department of Environmental Quality have found no threat to human health from the mounds themselves.

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