In a Dec. 19 memorandum, a Hanford engineering official recommended a halt to all activities affecting design, nuclear safety, construction and installation at the Hanford waste-treatment plant.

Gary Brunson, who has since retired from his position as director of the plant’s engineering division, said the work should be stopped to avoid “further nuclear-safety compromises and substantial rework.”

Brunson’s memorandum was made public on Wednesday by Hanford Challenge, a nonprofit organization that watchdogs safety issues at the Hanford nuclear reservation in Eastern Washington, where a $12 billion project is under way to build a plant to treat high-level waste. The plant is being designed to turn radioactive waste into glass logs through a vitrification process.

Disclosure of the memorandum comes one day after U. S. Energy Secretary Steven Chu and outgoing Gov. Chris Gregoire announced that a partial resumption of construction of the waste-treatment plant could occur.

“Based on insights gathered from … leading scientific experts, the Department (of Energy) is now confident construction activities can begin to be ramped back up,” said a joint statement released Tuesday by Chu and Gregoire, who ended her second term as governor on Wednesday.

In response to Brunson’s memo, the Department of Energy on Wednesday released a statement noting that it had stopped construction last year on work affected by technical uncertainties, and will only “ramp up construction work not impacted by the remaining technical issues.”

Tom Carpenter, executive director of the Hanford Challenge, said, “We think the memo is pretty clear. … That work should stop on the whole waste-treatment plant.”

Hal Bernton: 206-464-2581