TRI-CITIES — Work has begun to stabilize and remove highly contaminated hot cells that stand up to three stories high at Hanford.
It is the most difficult, complex and hazardous work that Washington Closure Hanford expects to face in demolishing old nuclear facilities at Hanford along the Columbia River, said Tom Kisenwether of Washington Closure.
The five hot cells being cleaned up are in the 324 Building in Hanford’s 300 Area just north of Richland. They were built to allow Hanford employees to work with highly radioactive materials without being exposed to radiation.
Workers would stand outside the hot cells and use controls to operate manipulators inside the cells, watching what they were doing through leaded-glass windows.
The tallest of the cells is narrow and stands three stories tall. But the largest has dimensions of 24-by-30-by-16 feet.
All have concrete walls 4 to 6 feet thick and lined with stainless steel. They have multiple crawl spaces, manipulator ports, ductwork, utilities, tanks, pipes, cranes and other systems and components cast into or attached to the facility.
Contamination within the hot cells has been fixed in place with a sealant and work has begun to fill the hot cells with grout or concrete.
Then the concrete-filled cells will be cut into blocks weighing 20 tons to almost 1,000 tons each.
The blocks will be packaged and taken to the Environmental Restoration Disposal Facility, a low-level radioactive waste landfill in central Hanford. The concrete will provide shielding for the radiation, allowing the hot cell blocks to meet the landfill’s standards for radioactivity.
Washington Closure has awarded a $43.5 million subcontract for the hot cell work to Northwest Demolition and Environmental. It is a joint venture.
The subcontractor expects to have the hot cells ready for demolition within a year.
Demolition will continue into 2013.
Washington Closure has a deadline to complete removal of not just the hot cells but also the 324 Building by October 2013.
The building is three stories, including one story below ground, and covers 102,000 square feet. The steel-framed building was built around the hot cells and is connected to them.
The building initially was used to examine fuel from Hanford’s plutonium-production reactors and develop ways to chemically reprocess the fuel to remove plutonium for the nation’s nuclear weapons program.
Later the building was used to help develop disposal methods for high-level radioactive waste, including vitrification, or glassification, which now is the preferred method internationally for immobilizing high-level waste.
Research work at the hot cells was completed and deactivation began in 1987, according to Washington Closure.
Cleanup of Hanford along the river corridor is progressing well, said Matt McCormick of the Department of Energy on Thursday at a meeting of the Hanford Advisory Board in Portland.
Among work coming up in the 300 Area near the Columbia River is demolition of the iconic 309 Plutonium Recycle Test Reactor and its emission stack. The reactor’s gray dome can be seen by drivers just north of Richland as they pass the 300 Area driving toward the Hanford Wye Barricade.
Fuel containing small amounts of plutonium was tested in the reactor during the 1960s for potential use in the commercial nuclear power industry.
In addition, in the next few months work should start to demolish the 337B Building, a high-bay building that was used to test Fast Flux Test Facility components. Both demolition projects will significantly change the skyline of the 300 Area.
DOE plans to have most cleanup work at Hanford along the Columbia River completed by 2015.
Talk to us
> Give us your news tips.
> Send us a letter to the editor.
> More Herald contact information.
