SPOKANE — The federal government is demanding that the company building a giant nuclear waste treatment plant in Washington state provide records proving that the steel used in the nearly $17 billion project meets safety standards. The U.S. Department of Energy says in a letter obtained by The Associated Press that records needed to ensure that the structural steel used in the project is safe are either missing or of “indeterminate quality.” “This condition is a potentially unrecoverable quality issue,” said the letter sent March 6 from the agency’s Office of River Protection in Richland to Bechtel National Inc., which is building the long-delayed plant to dispose of wastes created in the production of plutonium for nuclear weapons. The agency gave Bechtel National 14 days to provide proof that work on the project should continue. The plant is located on the Hanford Nuclear Reservation near Richland, which for decades made most of the plutonium for the nation’s nuclear weapons arsenal.