Hanford

Feds release plan to clean up highly radioactive building by Richland

B Cell, the hot cell where the leak happened, is seen from within the 324 Building.
B Cell, the hot cell where the leak happened, is seen from within the 324 Building. Courtesy DOE

The Department of Energy is proposing a seven-year plan to clean up a highly radioactive waste spill under a building at Hanford near Richland.

A public comment period on the plan, focused on the removal of the 324 Building, started this week and will continue through Sept. 9. A public meeting is planned at 5:30 p.m. Aug. 24 at the Richland Library.

“This is an important project,” said Stephanie Schleif, the transition project manager for the Washington State Department of Ecology. “Ecology is pleased to see DOE moving forward on the 324 Building.”

Washington Closure Hanford was working toward a legally binding deadline for DOE to have the building down in the fall of 2013.

But as DOE’s contractor worked toward that goal in 2010, it discovered a highly radioactive spill under the building from a hot cell leak that had gone undiscovered.

Hot cells were used to work with radioactive material, allowing workers to look through thick lead glass windows and manipulate equipment inside the cells.

The building, just north of Richland, is 1,000 feet from the Columbia River. There is no evidence now that the spill has migrated toward the river.

After the leak was discovered, a new plan was developed to install remotely operated equipment into the hot cell above the leak to clean up the spill, using the the cell as radioactive shielding to protect workers.

Hot cells were used to work with radioactive material, allowing workers to look through thick lead glass windows and manipulate equipment inside the cells.

As Washington Closure finishes out its DOE contract in less than three months, work on the 324 Building has been turned over to CH2M Hill Plateau Remediation Co.

CH2M Hill continues to evaluate plans and has conservatively estimated the work could take seven years, as outlined in a DOE plan prepared for the Department of Ecology and made public Tuesday.

A new Tri-Party Agreement deadline requires the work to be completed in fall 2021, and reconciling those timeframes is likely to become part of the public discussion of the plan given to the state.

DOE budget documents show that removing the contaminated soil is not expected to begin by fall 2018.

The preliminary plan given to the state proposes nearly two years for the first cleanup phase.

Remotely operated equipment in the hot cell with a leak, B Cell, would be used to remove the cell’s liner and floor slab. The material could be taken directly to the lined landfill in central Hanford for low-activity waste, or, if it is too radioactive, it could be placed in one of the 324 Building’s other hot cells.

The same remotely operated equipment would be used to dig up the soil beneath B Cell to about 13 feet deep. The contaminated soil also would be sent to a landfill or placed in another hot cell.

Then the hole beneath B Cell would be backfilled with grout. Grout also would be added to the three hot cells being used to hold contaminated soil and equipment.

The second phase of 324 Building cleanup would include tearing down the outer building structure, leaving the hot cells standing. They have concrete walls up to six feet thick to shield radiation.

2,000 tons weight of one filled hot cell

1,000 feet distance from Columbia River

Underground vaults once used for temporary storage of high- and low-level radioactive waste also would be left. The vault tanks already have been emptied and filled with grout.

Phase 2 is expected to take about 30 months, preparing the way for removal of the cells and vaults in Phase 3.

Hot cells and vaults could be cut away and removed as monoliths with walls intact to provide radioactive shielding. The largest piece would be the A Cell, said Elis Eberlein, Ecology’s 324 Building project lead.

Between its walls and grouted waste it could weigh about 2,000 tons. It now stands about 33 feet tall.

Vaults and cells are expected to be hauled to the central Hanford landfill, the Environmental Restoration Disposal Facility.

Phase 3, tentatively scheduled to take 19 months, would be followed with 15 months of remaining work, including demolition of the building foundation and digging up any nearby contaminated soil.

Comments may be emailed to Hanford@ecy.wa.gov or mailed to Stephanie Schleif, Washington State Department of Ecology, 3100 Port of Benton Blvd., Richland, WA, 99354.

For more information, go to the calendar at www.hanford.gov and click on any day of the comment period for a fact sheet. The fact sheet also includes a link to the full report.

Annette Cary: 509-582-1533, @HanfordNews

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