State and federal authorities on Thursday demanded $92 million from ExxonMobil Corp. to clean up oil that has lingered in Prince William Sound and the Gulf of Alaska since gushing from the Exxon Valdez tanker in 1989.

A $900 million settlement in 1991 included a “reopener” provision that allows a request for up to $100 million more in cleanup money, as long as government officials prove that wildlife or its habitat were still suffering spill-related setbacks that were unforeseen when the settlement was signed.