VANDERGRIFT — The state Department of Environmental Protection is inspecting a collapsed water treatment tank that leaked a small amount of contaminants into the Kiski River.

Agency spokesman John Poister said Thursday the spill at the Allegheny Technologies plant in Vandergrift wasn’t major and didn’t result in a fish kill. The contaminants included heavy metals.

Allegheny Technologies spokesman Dan Greenfield said the company is investigating the structural failure. He says no one was near the tank when it collapsed.

Greenfield says the waterway doesn’t require a cleanup at this point.

Residents reported seeing a red sheen on the Kiski River before sunset Wednesday.