CHICAGO (CBS) — The U.S. Environmental Protection Agency has accused a company that stores huge piles of petroleum coke on the Calumet River of violating federal regulations to limit emissions of harmful black dust, after tracing clouds of the powdery substance to the company.

WBBM Newsradio’s Bernie Tafoya reports residents living near the Calumet River and other parts of the Southeast Side long have complained of the black soot that they breathe in, and which stains their houses and dirties their windows.

The EPA said its investigation traced those clouds of black dust to KCBX Terminals’ piles of petroleum coke, or petcoke, a byproduct of the oil refining process. KCBX stores piles of the substance along the Calumet River.

The agency has issued a violation notice to KCBX for violating the federal Clean Air Act, and a State Implementation Plan requiring the company to limit emissions of petcoke dust.

“KCBX has been denying that’ it’s here; and we’ve been breathing it, eating it, living with it in our yards, in our garages, in our houses,” said Southeast Side activist Sue Garza. “It validates what the neighborhood’s been saying all along, so this is a big win for us.”

In February, KCBX claimed its own tests did not find any unusual amounts of petcoke in the air.

“Hopefully, this is one step closer into helping our fight to get rid of petcoke on the Southeast Side, and just ban it from the city altogether,” Garza said. “We need to get rid of this stuff. They need to not house it here, not put a roof on it, not tarp it, just get it out of here. People live here, you know? They need to get rid of it.”

Garza said asthma cases are on the rise in the neighborhood, and leaving piles of petcoke stored there will just lead to more health problems.

KCBX said it’s reviewing the federal complaint, and that it follows the law regarding storage of petcoke.

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