ANCHORAGE, ALASKA ? Federal and state authorities will seek more money from Exxon Mobil Corp. today to rehabilitate wildlife populations and clean up remaining oil from a devastating spill nearly 20 years ago, officials in Anchorage said.

Exxon has paid $900 million in restitution for the spill – the nation’s largest – which emptied 11 million gallons of crude oil into Prince William Sound in 1989.

A “reopener” provision in the settlement created a window from 2002 to 2006 in which the state and federal governments could claim up to an additional $100 million.

That reopener provision expires Sept. 1. State and federal officials must file a claim 90 days before that date, by the end of this week.