UPDATED 12/28/10 8:19 a.m.

KANKAKEE (AP) — An explosion at a Kankakee wastewater treatment plant has sent a liquid byproduct pouring into the Kankakee River, but officials say they don’t yet know if the substance is hazardous.

Kankakee Fire Chief Ron Young says he doesn’t know how much of the “black slurry” flowed into the river before the leak was stopped Monday afternoon.

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Firefighters say they’ve notified the Illinois Environmental Protection Agency and the state emergency management department.

The explosion earlier Monday leveled one building at the plant. No injuries have been reported. Young says seven plant employees are all accounted for.

He says methane gas used to run the plant may have built up and caused the explosion. An investigation is continuing.

Young says he was at his home two miles away and felt the impact.

The sludge did not enter the public drinking water system and the leak poses no apparent public health hazard, said IEPA spokeswoman Maggie Carson, citing preliminary information. Well water or private water systems are also unlikely to be affected, she said.

IEPA crews sampled downstream waters and found the pollution reached no further than a half-mile from the explosion, spokeswoman Carson said. Containment crews have already pumped out some of the substance as well, she said.

“It looks like it’s being contained promptly and has a limited impact,” Carson said. “There is not an apparent use of the river right now for recreational purposes, and it doesn’t pose an apparent public health risk.”

 © 2010 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed. Contributing: Sun-Times Media Wire.

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