A 360-foot-long tunnel at the nuclear reservation’s PUREX processing plant was discovered to be partially collapsed on May 9.
“Since this event began, our focus has been on protecting our workers, the public and the environment,” said Doug Shoop, manager of the DOE Richland Operations Office. “Installing this cover will provide additional protection as we evaluate other actions to further ensure the safe storage of the waste.”
The approximately 20-by-20-foot breach in the top of tunnel already had been filled with 53 truckloads of sand and soil to prevent any radioactive contamination exposed in the tunnel from becoming airborne……..
It is planned to keep rain from soaking into the eight feet of soil above the tunnel, which would add more weight to the roof. It also should help keep radioactive particles out of the atmosphere should more of the tunnel collapse.
It will be held in place by almost 150 concrete ecology blocks, each weighing 3,800 pounds, and cables from the ecology blocks criss-crossing across the berm.
Blocks had been placed along the plastic on the western side of the tunnel as it was rolled out on Friday. By 5 p.m. Saturday, a crane had placed ecology blocks along a third of the eastern side, with sandbags serving as temporary weights.
Work was expected to continue through Saturday night to place the rest of the blocks. The cable lacings are planned to be added on Monday…….
Next week DOE and CH2M will work with the state Department of Ecology, a Hanford regulator, on additional actions to ensure the safe storage of the waste until a decision is made on permanent disposal of the waste.
Department of Ecology officials have said filling the tunnel with grout is being considered.
The tunnel, built of creosoted timbers, was filled with eight flatbed rail cars in the early 1960s. They hold large pieces of equipment contaminated with radioactive waste from work in PUREX. The plant was used to chemically process irradiated uranium fuel to remove plutonium for the nation’s nuclear weapons program during the Cold War. Annette Cary: 509-582-1533, @HanfordNews http://www.tri-cityherald.com/news/local/hanford/article151783367.html
