HERMISTON, Ore. (AP) -- The incineration of chemical weapons at the Umatilla Chemical Depot resumed Wednesday after a brief shutdown to review safety violations.

Washington Group International, the contractor for the Army at the facility, voluntarily ceased processing Monday night to review the procedures.

The pause followed three notices of violations of the operating permit by the Oregon Department of Environmental Quality.

Depot officials say there was no danger to the public.

The permit violations occurred between July 2006 and February 2007. Twelve of the 15 were self-reported by Washington Group.

AP

Chemical weapons are stored in earth-covered igloos shown in this file photo at the Umatilla Chemical Depot in Umatilla, Ore.

"We stopped processing to be sure we fully understood DEQ's concerns and are addressing those concerns," said Doug Hammock, project general manager for Washington Group.

The state DEQ is charged with overseeing the safe storage and destruction of chemical munitions in the stockpile, which held about 12 percent of the nation's chemical weapons at its height.

Washington Group spokesman Hal McCune said violations tended to involve secondary waste disposal and how fast projectiles and chemical agent can be fed into the incinerator.

Violations can occur if cutoff procedures are not in place, he said.

Contractors are finishing the 155mm projectiles containing Sarin, a nerve agent, and hopes to be done this summer, McCune said. About 6,000 remain.

After a changeover that will take several months, he said, the facility will begin destroying other nerve gas, then mustard gas weapons.

The weapons are being destroyed under terms of an international treaty.