Digging is under way on one of the most hazardous waste burial grounds near the Columbia River at Hanford.
"We expect to find up to 2,000 drums containing everything from mildly contaminated clothing and debris to highly radioactive laboratory equipment and liquids," said John Darby, the Washington Closure Hanford remediation project manager for the 618-10 trenches, in a statement.
Excavation at the 618-10 Burial Ground has started with its 12 trenches, and planning is under way to safely remove 94 vertical pipe units there. The vertical pipe units, made of five bottomless 55-gallon drums welded together and buried upright, were used as a dump for highly radioactive wastes.
In excavating the trenches, workers already have uncovered about 30 55-gallon drums that enclose pipes surrounded by concrete. The concrete-lined drums typically were used to dispose of radioactive liquids.
Workers also have found about 200 bottles containing liquids, which will have to be evaluated and treated before disposal.
That's in addition to about 30 excavated drums that contain radioactively contaminated shavings in oil and miscellaneous debris, Darby said. Oil was used in some drums disposed at Hanford to keep uranium shavings or other material from igniting if exposed to oxygen.
Disposal records for the 618-10 Burial Ground, which was used from March 1954 until September 1963, are incomplete. But officials know it contains radioactively contaminated equipment and samples from research at Hanford. That could include contaminated laboratory instruments, bottles, boxes, filters, aluminum cuttings, irradiated fuel element samples, metallurgical samples and electrical equipment.
The Department of Energy faces a legal deadline to have the 618-10 Burial Ground cleaned up by 2018, but would like to have most environmental cleanup work completed in the 220 square miles along the Columbia River by fall 2015.
The start of the 618-10 project was accelerated thanks to federal economic stimulus money, said Mark French, DOE's project director for the Columbia River corridor.
DOE is spending $57 million of Hanford's American Recovery and Reinvestment Act money to get a good portion of the work done. Already that money has paid for two years of preparation to allow for the safe start of excavation of the trenches on the six-acre site.
The 618-10 Burial Ground is about six miles north of Richland a few hundred yards off Hanford's main highway.
* More Hanford news at hanfordnews.com.