OKLAHOMA CITY - A former Oklahoma oil and gas giant is at the center of the largest environmental cash settlement in history – 5.15 billion dollars.

The news doesn't help the reputation of Kerr-McGee, but it does help the company that bought Kerr-McGee eight years ago.

When Houston-based Anadarko Petroleum purchased Kerr-McGee in 2006, the company clearly wasn't thinking it would be saddled with the massive environmental liabilities that Kerr-McGee tried to rid itself of by spinning off its chemical business, Tronox, in 2005.

But it was. When Tronox declared bankruptcy in 2009, it sued Anadarko-slash-Kerr-McGee for misleading investors about the size of its environmental debts.

Among those many liabilities are pending clean-ups at several former Kerr-McGee sites in Oklahoma, the Cimarron Fuel Fabrication Site that's on highway 74, just south of Crescent, they processed uranium there.

Another location where they processed uranium was the company's refinery in Cushing. And there's another refinery in Cleveland, Oklahoma.

The new director of the state's Department of Environmental Quality says the settlement is good for the state.

"We will be able to fund cleanups that are ongoing, that had some initial settlement money funding," said Scott Thompson, Executive Director, DEQ. "But this should allow us to go further, so that's good."

In a statement, Anardarko CEO Al Walker said "This settlement eliminates the uncertainty this dispute has created, and the proceeds will fund the remediation and cleanup of the legacy environmental liabilities and tort claims."

DEQ director Thompson doesn't know yet just how much money will come to Oklahoma for cleanup, but says some money could also be used to clean up old Kerr McGee gas stations.