BRIDGMAN, Mich. (AP) — More than 1,000 gallons of sulfuric acid has leaked into a containment area outside a nuclear plant in southwestern Michigan.

The Nuclear Regulatory Commission reports that cleanup was ongoing Thursday at the Cook Nuclear Plant in Bridgman, southwest of Grand Rapids.

The agency says no acid was released into the environment or nearby drains. The leak was discovered Wednesday.

Plant spokesman Bill Schalk says a faulty gasket may be the cause and that a flange on a sulfuric acid tank's discharge valve was found leaking during an inspection. The tank was holding 3,800 gallons of the highly corrosive acid prior to the leak.

Radioactive waste specialist Kevin Kamps is with Beyond Nuclear, a watchdog group focused on the nuclear power industry. He says the leak is an example of "sloppiness" at Cook.