SPOKANE, Wash. (AP) – Two companies that do work at a former nuclear weapons production plant will pay fines of nearly $58 million for improperly billing the federal government for thousands of hours of work that were not performed.

Federal prosecutors on Tuesday afternoon announced the settlement involving the Hanford Nuclear Reservation, a Manhattan Project site near Richland, Washington.

The settlement was reached between Bechtel Corp. and AECOM Energy & Construction, which for years have been constructing a giant nuclear waste treatment plant to clean up the Hanford site, which produced most of the plutonium for the nation’s nuclear arsenal.

As part of the agreement, the contractors denied any liability with regard to further legal actions.

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