Chris Schneidmiller
WC Monitor
9/18/2015
Two more workers on remediation of the Hanford Site’s Plutonium Finishing Plant (PFP) underwent decontamination last month after coming into contact with radiological particles, according to the latest Defense Nuclear Facilities Safety Board site representative report.
Both events occurred during the continuing effort to reduce the size of the HC-9B glove box in the facility once used to convert liquid plutonium into solid form for nuclear weapons. They are indicative of persistent issues plant decommissioning contractor CH2M Hill Plateau Remediation has faced in use of OSHA level B suits during three high-risk operations that require supplied air within the PFP cleanup, the DNFSB officials said in their Aug. 14 report. Both employees were “decontaminated to less than detectable levels,” the document says.
The first skin contamination resulted from a faulty seam in the protective suit, and was the fourth such seam failure in three months. Two of those incidents involved failures of “non-critical seams” that were found during pre-use checks of the suits, the DNFSB said. In the other cases, workers suffered skin contamination when the faulty seams were not found prior to the suits being used.
No cause had been identified as of the time of the report for the second of the latest incidents, “despite recent changes in work practices and modifications to the inner PPE suit worn by the workers,” the DNFSB report states.
“The work team noted that the ongoing problems appear to be linked to a recent redesign of the suit, and that the type of loose surface contamination contained in the current work area is highly mobile compared to that found in other work areas,” the DNFSB officials reported. “The contractor decided to restrict work using the level B suits pending completion of a review of the suit design, work practices used to doff the suits, and inner PPE selection, and is engaging with the vendor to resolve quality issues.”
There have been no further incidents since the Aug. 14 DNFSB report, according to CH2M Hill spokesman Destry Henderson. “CH2M has initiated a causal analysis into the seam failures, and we are working with the manufacturer to ensure the suits are inspected before they are shipped,” he said by email on Thursday. “Employees at PFP are thoroughly inspecting the suits before use and have since found no issues with seams.”
In 1,200 entries into areas of the facility that require workers to use supplied air, there have been only seven skin or clothing contamination incidents, CH2M noted on Thursday.
The Plutonium Finishing Plant project is part of the much larger cleanup of the Hanford Site, which for decades supported the U.S. nuclear weapons program. Prior reports from the DNFSB cited other events of concern at the PFP, including contamination incidents involving workers using OSHA level B suits in late July and two breaches of the radiological work permit void limit for the facility in early August. Information submitted during CH2M Hill’s quarterly Corrective Action Review Board meeting also “confirmed previously noted adverse trends … related to the number of radiological and worker injury events,” the Aug. 14 DNFSB report says. An Aug. 11 CH2M Hill management concern report covering six months highlighted one contamination incident and two worker injuries – one in which an employee trip and one in which an employee suffered an injured shoulder while using a pry bar – as being indicative of an unfavorable trend. The company is “analyzing these events, and from that analysis will develop corrective actions,” Henderson stated.
CH2M Hill is continuing work on decontamination and ultimate demolition of the PFP. The company is about halfway through development of its plan for a “controlled and methodical” demolition, the DNFSB said.
The facility is roughly 84 percent ready for demolition, Henderson said. Workers are now extracting the last of the plant’s plutonium processing equipment, as well as remediating the Plutonium Reclamation Facility canyon and readying chemical tanks to be removed from the structure.
The Plutonium Finishing Plant is expected to be razed by the end of fiscal 2016, Mark Whitney, principal deputy assistant secretary on the DOE Office of Environmental Management, said Thursday during a panel discussion in Washington, D.C. The entire project is now estimated to cost in the mid-$900 million range.
