Exxon Mobil Corporation was court-ordered this week to pay close to $500 million in interest on punitive damages for the Exxon Valdez oil spill off Alaska twenty years ago. This doubles the payout to Alaska Natives, fishermen, business owners and others harmed by the 1989 oil spill.

The ruling was issued by the 9th U.S. Circuit Court of Appeals in San Francisco. In June of last year, the U.S. Supreme Court set punitive damages at $507.5 million. Eight weeks later, the court declined to say whether Exxon would have to pay interest on the punitive damages awarded in the oil spill and instead sent it back to the appeals court.

This weeks decision would double the average payout of about $15,000 for the nearly 33,000 claimants.

“We’re just happy that we’ve cleared another hurdle, and hopefully we can get the case tied up as soon as possible,” Stanford University law professor Jeffrey Fisher, an attorney for the plaintiffs, told The Associated Press on Monday. “What we want more than anything now is just to bring this case to a close.”