A worker at the Energy Department’s Hanford Site near Richland, Wash., suffered no internal contamination after being exposed to radiation while assigned to preparing the Plutonium Finishing Plant (PFP) for demolition.
The July incident was not disclosed until late last month in the Defense Nuclear Facilities Safety Board (DNFSB) site representative report for the week of July 25.
After multiple requests for comment, the Energy Department responded to questions in writing but would not authorize a representative to speak on the record about the incident, which occurred July 27 in a part of the PFP called the Plutonium Reclamation Facility canyon.
CH2M Plateau Remediation Co. is responsible for tearing down PFP under a 10-year Hanford Site Central Plateau Remediation cost-plus contract awarded in 2008 and potentially worth $5.6 billion. This is the second skin contamination since December 2015 at PFP, which has consistently lived up to its billing as the most dangerous demolition project in the DOE complex.
“The most likely cause of the skin contamination was cross contamination that occurred during removal of personal protective equipment,” the DNFSB report reads.
Neither DOE nor DNFSB disclosed the element to which the worker was exposed, nor quantified the level of contamination. The source of the contamination is believed to be the concrete wall of the reclamation facility’s canyon, parts of which the worker had scraped off for sampling ahead of the reclamation facility’s planned demolition this month.
The worker immediately submitted to a bioassay on July 28 following the contamination. Around mid-August, test results came back indicating the employee had received no internal dose or contamination.
While demolition of the PFP’s reclamation facility canyon is set to begin in the coming weeks, the entire Plutonium Finishing Plant will not be demolished until Sept. 30, 2017 — a year later than planned. In February, following the December skin contamination incident, CH2M replaced top project managers at PFP and began requiring workers to use additional protective gear in the building.
That, and ongoing technical and safety challenges at PFP, slowed the pace of pre-demolition activities enough that by May, DOE was negotiating a deadline extension with the Washington state Department of Ecology, as first reported by Weapons Complex Morning Briefing. DOE and its state regulator announced the one-year extension in July.
During the Cold War arms race, the nearly 70 year-old PFP pressed plutonium into the hockey puck-shaped buttons that eventually were fitted into the cores of U.S. nuclear warheads.
