An excavator later found to have radioactive contamination was taken from Hanford to a Tri-Cities shop for maintenance. Workers at Powers Equipment in Pasco are not believed to have been put a risk, but some contaminated items were found there after the work was completed. The problem was discovered Monday afternoon when the excavator was returned to a Washington Closure Hanford project after five days at the shop, which had leased the excavator to a subcontractor. A survey found radioactive contamination in grease on the bucket joint and on the turret deck. A subsequent survey of Powers Equipment found contamination on a pin removed from the excavator arm, shims used to stabilize the pin and on grease on a large coupler removed from the excavator and replaced.
The radioactive contamination was contained in the grease, which kept workers from inhaling it, said Earl Fordham with the Washington State Department of Health. The level of contamination was low, he said. The excavator was surveyed before it left a radiological control area at Hanford. But the equipment that contained the contaminated pin, the likely source of contamination spread in the grease, was not disassembled during the Hanford survey, said Jerry Simiele, Washington Closure radiological control and industrial hygiene manager. Washington Closure will be reviewing its protocol for releasing equipment from the site.