Washington Closure Hanford has begun removing waste from vertically buried pipes at the Hanford Site in Washington state for the first time. Just two Hanford burial grounds, 618-10 and 618-11, used the disposal method, called vertical pipe units. The two were saved as the last burial grounds in the river corridor for remediation because they were expected to be the most complex and challenging. Work has started first on the 618-10 Burial Ground, with overcasings driven into the ground around 80 of the 94 vertical pipe units. Most of the vertical pipe units were made of corrugated piping or 55-gallon drums welded together after their tops and bottoms were cut off. However, 14 were made of thick-walled steel and work has not started on them.
Washington Closure is using an auger to chew through the contents within the overcasings, including the vertical pipe units, the waste they hold from research and uranium fuel fabrication, and the band of soil between the walls of the vertical pipe units and the overcasings. With augering well underway this spring, Washington Closure began retrieving waste from one of the augered vertical pipe units last week. The waste was lifted out using a clamshell shovel equipped with a camera and light. The waste was deposited into steel boxes where it was mixed with grout for disposal at the Environmental Restoration Disposal Facility in central Hanford.
At the start of this week Washington Closure workers had augered 38 vertical pipe units, which is well ahead of schedule. The contractor had planned to auger the waste in 28 of the vertical pipe units before its contract expires at the end of September 2016. Washington Closure could auger 80 of the vertical pipe units before work at the burial ground is turned over to CH2M Plateau Remediation Co. this fall, according to the Department of Energy. To date, all of the vertical pipe units augered had sufficiently low levels of transuranic waste that their contents can be disposed of at the Hanford landfill, rather than set aside to be eventually shipped to the Waste Isolation Pilot Plant in New Mexico, which is scheduled to reopen in December.
