The Plutonium Finishing Plant (PFP) at the Department of Energy’s Hanford Site continues to live up to its billing as the most dangerous and complicated cleanup at the former plutonium production facility near Richland, Wash., with a government watchdog disclosing Wednesday some close calls involving one of the plant’s radio-contaminated glove boxes.
Difficulties with the facility’s last five glove boxes — once used to protect the workers who processed liquid plutonium into a solid form for nuclear weapons cores — factored into DOE’s acknowledgement last month that it might blow a Sept. 30 deadline to tear the nearly 70-year-old PFP down to its concrete floor. Demolition now is not slated to begin until after a readiness review scheduled for July 18; in the meantime, highly contaminated glove boxes continue to prove a challenge to a speedy demolition.
According to reports released Wednesday by the Defense Nuclear Facilities Safety Board — an independent U.S. entity that polices nuclear safety issues across the DOE weapons complex — contractor CH2M Plateau Remediation Co. narrowly avoided shipping an irradiated component associated with the HC-4 removal to an off-site facility that might not have been authorized to receive it.
HC-4 was removed the week of May 9, but might have been removed sooner, according to DNFSB. CH2M lost ground because it brought the wrong kind of shipping container to haul away HC-4, and due to general clutter in PFP that blocked the path of the workers charged with removing the glove box. The glove box pieces were too big to fit through PFP doors and so had to be carried through holes CH2M knocked in the facility’s walls.
The reports disclosing the latest glove-box snafus are based on monitoring by DNFSB site representatives from May 2-13, weeks before DOE publicly acknowledged it was in discussions with state regulators to change the milestone for completing PFP demolition. Those talks are ongoing, a spokesperson for the DOE Richland Operations Office said by email Thursday.
According to the latest published DNFSB reports, a CH2M worker prevented the shipment after double-checking a calculation used to determine whether contaminated material can be safely received by an off-site facility.
“The worker’s questioning attitude and positive action prevented non-compliant shipment of the material, as well as a potential exceedance of the receiving facility licensed allowance for the material,” DNFSB wrote in its largely laudatory assessment of the latest challenges at PFP.
HC-4 is one of the last five glove boxes that eventually must be removed from the Plutonium Finishing Plant. Another, HA-9A, was removed from PFP in February. The most recent glove box removed prior to HA-9A was WT-1, which was yanked in 2015. Two other glove boxes will only be removed once PFP demolition begins.
Some contaminated PFP equipment like the glove boxes are shipped off-site to an undisclosed location to be cut into smaller pieces more easily suitable for storage as transuranic waste at the Waste Isolation Pilot Plant near Carlsbad, N.M. Such waste comes back to Hanford for final processing before it is shipped to New Mexico. The Waste Isolation Pilot Plant has been closed since a pair of accidents in 2014 and is set to receive new waste shipments early next year.
It was not immediately clear from the DNFSB reports whether the contaminated component from HC-4 removal had been shipped off-site to a qualified facility. The Richland Operations Office spokesperson had no immediate comment about the shipment.
The Plutonium Finishing Plant is in one sense a microcosm for the nationwide legacy nuclear cleanup overseen by DOE’s Office of Environmental Management: low-hanging fruit has long been picked, and what remains is both difficult to reach and daunting to remove.
Cleanup at PFP started in the 1990s, when workers began stabilizing the plutonium solution left over in the building after the end of the Cold War, shipping the last of it off-site in 2009. Before DOE got started on cleanup, PFP contained 238 glove boxes. The vast majority of these now have been removed. Likewise, some 80 percent of PFP’s 81 facilities have been torn down.
However, the main processing building and its big glove boxes have slowed demolition work in the last year or so, owing to the challenges associated with the glove boxes themselves, and to the omnipresent contamination hazards common at any legacy nuclear site.
Beginning in 2015, and continuing throughout into year, DOE has dealt with incidents of worker skin contamination and even very low levels of internal worker contamination on-site. CH2M replaced top project managers in February, and now requires workers to wear protective clothing and breathing apparatus for some PFP tasks. In addition workers may not perform multiple tasks requiring protective gear at any one time.
Nevertheless, the close calls continue. In the same batch of reports detailing difficulties with glove box HC-4, DNFSB reported that a CH2M worker’s suit was torn in PFP, prompting the person to swiftly exit the facility.
“Contamination was found inside the Level B suit, but it did not breach the inner set of anti-contamination clothing,” the DNFSB’s report reads.
