A contractor at the Hanford nuclear reservation and a metal recycler have agreed to pay more than $84,000 for a spill of oil containing polychlorinated biphenyls from a transformer.

Under the deal with the Environmental Protection Agency, Fluor Hanford is paying $54,800 and Twin City Metals $30,000 for the blunder, which may have contaminated workers at the recycling company in Kennewick and at Joseph Simon and Sons of Tacoma, a recycling business where the transformer was sent last year.

Dielectric fluid, a mineral oil containing PCBs that kept the transformer from overheating, should have been drained before Fluor removed it and 59 others from the power grid for recycling, according to a statement issued by Michael A. Bussell, EPA regional director of compliance and enforcement in Seattle.

“Risks to human health and the environment could’ve been greatly reduced, at a fraction of the cost, if this was handled correctly in the first place,” Bussell wrote. “By carefully handling all transformers, and diligently cleaning up any spills that occur as quickly as possible, damage can be prevented and costly cleanups avoided.”

PCBs can collect in the human body and cause liver damage or cancer.

About 50 gallons of oil containing PCBs at 250 parts per million leaked after a fin broke when the undrained transformer was dumped onto the ground at Twin City in 2006, a day before the transformer was shipped to Tacoma.

Fluor officials claimed they quickly dispatched cleanup personnel to both companies. But, according to the EPA, the Hanford contractor began cleanup only after a week when the spill was confirmed to involved PCBs.