On Thursday, workers at Umatilla's chemical weapons incinerator put a lot behind them: one year, five fires, 163 tons of sarin nerve gas and 31,098 rockets. Since destroying its first rocket Sept. 8, 2004, the incinerator has processed just over a third of the sarin-tipped rockets stored at Umatilla Chemical Depot near Hermiston.

That is slightly less than 5 percent of the total nerve agent at the depot. Within two weeks, crews hope to destroy four bulk containers of sarin, then incinerate bombs holding the deadly nerve agent.

They will continue processing rockets, work put behind schedule after errors and five rocket fires forced slowdowns to make time for training and investigations.

- Andy Dworkin