Tri-Cities company awarded $10 million to help prevent a Hanford disaster

A Tri-Cities company has been awarded a $9.5 million subcontract on a project planned to prevent the potential release of radioactive material into the air or ground at the Hanford nuclear reservation.

Apollo Mechanical Contractors Inc., of Kennewick, has been picked by Hanford contractor Central Plateau Cleanup Co. to work on construction needed to move 1,936 capsules of highly radioactive cesium and strontium out of underwater storage in a concrete pool.

The concrete has deteriorated from radiation exposure over decades, and the pool is at risk in a severe earthquake. Loss of water and cooling could damage the capsules and release highly radioactive material into the environment, potentially putting workers and the public at risk.

A 2014 memo from the Department of Energy Office of Inspector General said the central Hanford facility — the Waste Encapsulation and Storage Facility, or WESF — was the DOE facility at the greatest risk in the case of a natural disaster beyond what it was designed to sustain.

Apollo will complete the structural and utility modifications to WESF that will be needed to transfer the capsules from underwater storage to stainless steel containers.

Those will be packed into steel-lined, reinforced concrete casks for storage standing upright on an outdoor pad nearby in the center of the Hanford site.

Because water will no longer be used to cool the cesium and strontium, the casks will draw in air, which will not come in contact with the waste, for cooling.

Apollo also will install the new cask storage system under its new contract. The concrete foundation for the outdoor storage area already has been poured.

“Moving the capsules will enable the planned deactivation of WESF and will reduce the risk and significantly reduce the annual costs for storing the capsules,” said Gary Pyles the project manager for DOE.

Waste from Hanford tanks

The Hanford nuclear reservation in Eastern Washington was used from World War II through the Cold War to produce about two-thirds of the plutonium for the nation’s nuclear weapons program.

Waste from chemically processing irradiated uranium fuel to remove plutonium was stored in 177 underground tanks.

The cesium and strontium were recovered from Hanford’s underground waste tanks from 1974-85, packed in corrosion-resistant capsules and placed in underwater storage at WESF.

The capsules, which are about 22 inches long, hold material with 106 million curies of radioactivity, or about 30 percent of the total radioactivity at Hanford.

The 13 feet of water now covering them helps cool the capsules and protects workers from radiation.

To make sure the move of the capsules goes smoothly, a full-scale mock-up of parts of WESF, including a hot cell and the truck port through which the cesium and strontium capsules will be transferred has been constructed.

The mock-up allows workers to safely train, test equipment and develop procedures before performing the work in a radiological environment.

DOE has a legal deadline under the Tri-Party Agreement to have the 1,936 capsules moved to dry storage by August 2025.