The Umatilla Chemical Depot will end 180 jobs Thursday as work continues to close the plant that destroyed more than 1 million pounds of chemical agents and munitions.
The last of six furnaces was shut down Friday.
The East Oregonian reports about 525 employees continue to work at the plant, which is operated by the URS company. Closure work will continue through 2014.
It took more than seven years to destroy all the chemical weapons at the depot. Furnaces destroyed rockets, mines, spray tanks and containers. The last furnace was used to destroy protective suits, filters and other secondary waste.