A panel of experts studying options for stabilizing the second radioactive waste storage tunnel at the Hanford Site’s PUREX Plant is scheduled to meet in teleconference for a second time today.
The group’s first meeting, held a week earlier, was largely organizational, with no decisions made or a firm schedule set for future meetings. The expert panel includes eight representatives from the Department of Energy, academia, and industry, plus supporting experts from CH2M-UK and the Colorado School of Mines.
The Washington state Department of Ecology ordered DOE to provide a proposed plan by Aug. 1 for stabilizing Tunnel 2, which was found to be at “high” risk of collapse in the wake of the partial collapse of Tunnel 1. Instead, the federal agency told the state on Aug. 1 that it wanted to convene an expert panel to consider options for stabilizing the tunnel to prevent a collapse and release of radioactive materials, while still leaving the waste accessible for eventual cleanup. The Department of Ecology said using experts to evaluate proposals has merit if it results in a robust solution. But it remains concerned that DOE will not meet its next state-ordered deadline: submitting a proposal by Oct. 2 to ensure the safe storage of the waste within both PUREX tunnels.
During the Cold War, the Plutonium Uranium Extraction Plant recovered plutonium from irradiated fuel rods as part of the Hanford Site’s mission to supply the material for use in the nation’s nuclear deterrent. Contaminated equipment was placed in the two underground tunnels: Tunnel 1, built in 1956 largely of creosoted timbers, holds eight railcars of waste; Tunnel 1, build in 1964 of steel and concrete, holds 24 railcars of waste.
On May 9, the older and shorter of the two PUREX plant waste storage tunnels was discovered to be partially collapsed. Hanford officials moved quickly to fill the breach with sand and soil, cover the length of the tunnel with heavy plastic, and make plans to fill the tunnel with grout. Some stakeholders complained that the public did not have a chance to comment on the plan to grout the first tunnel, but Hanford officials said emergency action was needed to prevent a further collapse. Hanford cleanup contractor CH2M Hill Plateau Remediation last week issued a $2.8 million subcontract to Intermech to grout the tunnel, with work due to start this month and wrap up in December.
The Energy Department is considering a wider range of options for stabilizing the second PUREX tunnel. Options that have been proposed include covering the tunnel with plastic, a tent or a building; filling it with grout or other substance, such as sand; performing a controlled collapse of the tunnel; or proceeding with removal of the waste.
