WISCASSET — In an ongoing settlement, the federal government on Thursday agreed to pay Maine Yankee Atomic Power Co. $35.7 million for failing to remove 550 metric tons of spent nuclear fuel that’s been sitting in Wiscasset since the nuclear plant stopped generating power in 1996.

The money, which will be returned to Maine ratepayers in the future, is meant to reimburse Maine Yankee for the costs incurred in storing the spent fuel between 2003 and 2008. It follows a similar award of $81.7 million the federal government paid to Maine Yankee in February 2013.

Maine Yankee began generating power in 1972, and was decommissioned in 2005 after an eight-year process.

The federal government is contractually obligated to dispose of the 550 metric tons of spent nuclear fuel, which is stored in Wiscasset, but has failed to do so. Storing the spent fuel costs Maine Yankee roughly $9 million a year, Eric Howes, a Maine Yankee spokesperson, told the Bangor Daily News in February.

The federal government will also award damages of $126.3 million to Connecticut Yankee Atomic Power Co. and $73.3 to Yankee Atomic Electric Co., according to a news release.

Connecticut Yankee, Yankee Atomic and Maine Yankee have been in court for 14 years seeking reimbursement for the storage costs.

“We urge the federal government to fulfill its commitment to remove this material from our sites without further delay and to avoid filing a costly appeal that would only prolong the legal process and adversely affect ratepayers and taxpayers,” Wayne Norton, president of Yankee Atomic and Connecticut Yankee and chief nuclear officer of Maine Yankee, said in a statement released Thursday.