High hazard glove boxes gone from Hanford plutonium plant

Hanford workers have completed one of the three high-hazard projects left for last before the demolition of the nuclear reservation’s Plutonium Finishing Plant.

Among the plant’s 238 glove boxes were two oversized boxes that stood 12 feet high and were eight feet wide. During the Cold War, workers would reach their hands through attached gloves at three levels on the tall boxes to reach inside to process plutonium in a liquid solution into oxide powders or metal pucks for the nation’s nuclear weapons program.

They were too large and too contaminated to be removed from the building in one piece.

Both of those glove boxes, the final ones in the main portion of the plant, have been disconnected, cut up and packaged into boxes that will be stored at Hanford until they can be sent for disposal at a national repository in New Mexico.

Plant workers have done “amazing work in an environment most of us cannot comprehend from a hazards perspective,” said Tom Bratvold, CH2M Hill Plateau Remediation Co. acting vice president at the plant.

It’s not only its size that made the work challenging, but the amount of plutonium contamination that remained inside them.

It was a particularly flighty form of radiation, and workers wore the type of protective gear saved for some of the most hazardous projects at the plant. The suits are filled with air to create higher pressure within the suits than outside them to protect workers from airborne contamination. They use supplied-air respirators.

Workers also had to contend with significant levels of radiation, Bratvold said. They used lead blankets as shields, reconfiguring their arrays of blankets almost daily to minimize radiation exposure.

“This is work that hasn’t ever been done before at Hanford,” said Craig Krueger, a CH2M Hill nuclear chemical operator on the team that removed the two glove boxes, in a statement.

The work not only was some of the most hazardous performed at Hanford, but it is “right up there with the most hazardous work performed at any of the DOE nuclear weapons production sites,” said Tom Teynor, the Department of Energy project director.

Work has been under way to clean out the plant since the 1990s, when efforts began to stabilize plutonium in a liquid solution left there at the end of the Cold War. In recent years, workers have been cleaning out and removing tanks and contaminated glove boxes.

Work started on the two oversize glove boxes in June 2015. The first one was cut up and removed in early August, and the second one was completed this month.

Some hazardous work remains in the main portion of the Plutonium Finishing Plant, but it is not so hazardous as to require the air-filled suits.

Parts of a contaminated ventilation system and a vacuum system used to transfer plutonium-rich material between glove boxes still must be removed. The plant also has asbestos and other hazardous materials.

Not all glove boxes have been removed. The main plant includes 13 smaller glove boxes that are packaged and staged for removal from the facility immediately before and during demolition.

The remaining two high-hazard projects at the plant include work in two additions to the plant for specialty projects.

Workers finished covering the floor of the Plutonium Reclamation Facility’s long, tall concrete room — its “canyon” — with grout in January. Next, they will decontaminate the steel racks, or “strong backs,” used to hold long, skinny tanks. They also will decontaminate the walls of the room.

The facility was used during the Cold War to increase plutonium production by recovering it from scrap material that otherwise would have gone to waste.

It has the last four glove boxes at the Plutonium Finishing Plant that must be prepared for demolition. Because they are an integral part of the Plutonium Reclamation Facility and its ventilation system, they must remain intact until work is completed.

The crew that cut up the oversized glove boxes will tackle the other remaining high-hazard project, the Americium Recovery Facility, which will require the protection of the air-filled suits.

The facility was the site of the glove box explosion that injured Harold McCluskey, who came to be called the Atomic Man, in 1976. The glove boxes have been removed, but chemical feed tanks still must be isolated and other tasks completed.

Bratvold expects to start demolition of the Plutonium Finishing Plant by September, beginning with the Plutonium Reclamation Facility and then moving on to the Americium Recovery Facility.

Work has slowed some to focus on safety as high hazard work is done, including doing only one job at a time that requires the air-filled suits.

The legally binding deadline for demolition to slab-on-grade to be completed is September, and if DOE does not think it can meet that deadline, it will notify regulators.

Removing the glove boxes from the main plant brings DOE a significant step closer to being ready to start demolishing the plant, Teynor said.

This story was originally published February 25, 2016 at 9:16 AM with the headline "High hazard glove boxes gone from Hanford plutonium plant."