The U.S. Department of Energy and contractor CH2M HILL Plateau Remediation Company are removing the Plutonium Finishing Plant, one of the most complex nuclear decommissioning and demolition projects at the Hanford Site in southeast Washington state.
The Plutonium Finishing Plant, also known as Z-Plant, operated from 1949 to 1989 and represented the final step in plutonium production at Hanford. At this facility, plutonium was processed into solid, hockey-puck sized “buttons” and plutonium oxide powder that could be safely shipped to the country’s weapons production facilities. The plant produced nearly two-thirds of the nation’s plutonium stockpile.
The plant poses a monumental cleanup challenge – to safely clean out and demolish the facility to protect human health and the environment.CH2M HILL Plateau Remediation Company (CH2M) is responsible for safely and compliantly demolishing the aging facility to its concrete foundation.
The risks and challenges of this task include:
- Several pounds of residual plutonium and americium in the facility
- 238 large, contaminated enclosures called glove boxes
- 52 pencil-shaped tanks once used for controlled nuclear reactions
- More than a mile of highly contaminated vacuum system piping
- A critical ventilation system years past its design life
- Complex configurations of contaminated glove boxes, systems and equipment
- Dozens of facilities that make up the plant
CH2M partners with the U.S. Department of Energy (DOE) Richland Operations Office and other DOE sites to find the right tools and techniques to safely and efficiently remove the plant’s complex hazards. Examples include:
- • Using employee-recommended breathing equipment and protective suits to more safely and efficiently enter highly contaminated work zones
- • Improving and standardizing operations of respiratory equipment using manufacturer-approved modifications
- • Installing temporary safety systems to maintain decontamination and demolition work inside the facility while allowing shutdown of aging and expensive safety systems
While fewer than five percent of the glove boxes remain, and all 52 pencil-shaped processing tanks have been removed, high-hazard and challenging work continues.
In 2015, CH2M removed the last of five glove boxes from the historic McCluskey Room. An explosion in a glove box in the 1970s left the room highly contaminated and closed off for many years.
Additionally, employees recently cut apart and removed from the building two glove boxes that are each two stories high.
In the coming months, CH2M will begin demolishing the entire plant.