Work on one of Hanford’s most hazardous projects could restart next week, nearly nine months after a spread of radioactive contamination forced a shutdown.
Demolition of the nuclear reservation’s highly contaminated Plutonium Finishing Plant was halted in December after a spread of radioactive particles was discovered for a second time last year.
In all, 42 workers were found to have inhaled or ingested small amounts of radioactive particles and workers drove contaminated cars off the nuclear site.
The planned restart is limited, with some of the less hazardous work remaining to be tackled first, and with new policies and procedures in place to keep workers safe and help restore public confidence.
The Department of Energy this week approved its contractor CH2M Hill Plateau Remediation Co. to restart the less hazardous work at the plant following a two-week management review in August and some actions on a few findings from the review.
Hanford regulators also lifted a stop-work order issued in January, but only to allow the less hazardous work.
“The U.S. Department of Energy has adopted stronger safety measures that should reduce the risk to workers and the environment,” said Alex Smith, manager of the Nuclear Waste Program of the Washington state Department of Ecology. The agency is a Hanford regulator along with the federal Environmental Protection Agency.
The pace of work will be slower, said Tom Teynor, DOE project director for the plant.
CH2M will restart work by removing contaminated demolition debris left on the ground and unpackaged at the main part of the plant after the December halt to most work.
In December 2018, work could advance to tearing down one of the remaining sections of the Plutonium Finishing Plant with the least radioactive contamination.
Another management review will be required before DOE and Ecology will consider letting the higher hazardous work at the plant resume.
The plant was used during the Cold War to process two-thirds of the plutonium for the nation’s nuclear weapons program. Plutonium came into the plant in a liquid solution and was turned into solids that could be sent to weapons production plants.
The second phase of work will start with tearing down the most contaminated part of the main plant, where workers did much of the processing in two long lines of glove boxes, reaching their hands through protective gloves attached to portals to do the work.
Then workers would turn to the most highly contaminated part of the plant, the Plutonium Reclamation Facility, which was added to one end pf the main plant to reclaim plutonium from scrap waste during the height of the Cold War.
In December work had almost been completed to tear down the facility, when the spread of contamination was discovered.
Checks of workers found that 42 had inhaled or ingested small particles of plutonium or other radionuclides in December and in an earlier airborne spread of contamination in June.
Specks of contamination were found after the December incident on seven worker cars, with at least two driving home and one of them a rental car. Checks of several worker homes found no radioactive contamination.
Contamination also was found on government vehicles used at the site.
Very small amounts of radioactive contamination were found to have spread from the plant for miles in December and earlier, with contamination found near the Columbia River and at the site’s Rattlesnake Barricade just off public Highway 240.
Plans call for continuing open air demolition of the plant using heavy equipment.
But as work resumes, only small amounts of demolition debris will be allowed to accumulate before it is removed and more demolition done.
Concerns were raised after contamination became airborne in December that the debris piles were not adequately controlled to keep radioactive particles in the debris from spreading.
Air monitoring and checks for the spread of radioactive materials will be more frequent and more extensive, allowing any problems to be addressed quickly and before they grow.
Workers have been moved to offices away from the plant and are given rides from there rather than being allowed to drive their personal vehicles to the plant.
In August, with the start of the management assessment required for restart just days away, a contaminated piece of equipment was mistakenly loaded onto a truck and taken into north Richland before being returned to the nuclear reservation.
The incident was part of the management assessment Aug. 13-23.
Jacobs Engineering, which owns CH2M at Hanford, assembled an independent team for the review, with DOE also providing oversight, both with Hanford and headquarters officials. Hanford regulators were invited to observe and the Defense Nuclear Facilities Safety Board monitored the process.
“The management assessment went really well,” said Jason Casper, the Jacobs demolition resumption manager for the plant.
It resulted in limited changes, including repeating an emergency drill that had to be curtailed because of smoky air and improving controls for removing equipment from areas where radiological materials should be contained.
If new measures to better control radioactive contamination prove to be effective, the Washington state Department of Ecology will fully lift the stop-work order and allow the high risk demolition to proceed, Smith said.
The restart of the second phase could be authorized in late winter or early spring.
The plant could be torn down to the ground and sampling for any remaining radioactive material could be completed by summer 2019.
Work began to prepare the plant for demolition about two decades ago, starting with the stabilization of plutonium left in the plant in a liquid solution at the end of the Cold War. Demolition started in late 2016.
“All of us would like to see this long-running project successfully and safely completed,” Smith said. “It will be a great day for Hanford and for the state of Washington when the Plutonium Finishing Plant complex becomes a historical footnote rather than an ongoing threat to human health and the environment.”