RICHLAND, WASH. - After two years of preparation and characterization, the Department of Energy's (DOE) River Corridor contractor, Washington Closure Hanford, has begun remediation of one of the most hazardous burial grounds tackled to date on the Hanford Site's River Corridor.
The $57 million American Recovery and Reinvestment Act project began with nearly two years of preparation and characterization before reaching their current phase of work -- digging into 618-10 Burial Ground's trenches.
"This is one of two burial grounds we'll be remediating that received the higher levels of radioactive waste from the laboratories that did the work in the 300 area," says John Darby, the WCH 618-10 Burial Ground Project Manager.
Darby estimates they've removed about 30 concrete lined drums that contain radioactively contaminated shavings and oil, and miscellaneous debris
"We did a considerable amount of research but the records are incomplete, so we have a pretty good idea of what to expect, but still you have the risk of running into some things that weren't in the records. So we have to be ready for any unknowns at any time."
Workers have also found around 200 bottles containing liquids, which will have to be evaluated and treated prior to disposal. The bottles are unmarked and can be anything.
"We're finding a variety of bottles that are unmarked, unlabeled, contain different materials, liquids. The bottles are all different," says Jamie Zeisloft, the project lead from the Department of Energy.
Zeisloft says, the workers in the trenches are the ones who sort through the material, and safety is their main concern.
"The workers that are in the trenches suited up, have to handle each one of those right now. We're looking at a new method and we're working with the US Environmental Protection Agency to come up with a method that's safer and more efficient," says Zeisloft.
In addition to the trenches, the six-acre site contains 94 vertical pipe units (VPUs). The VPUs consist of five bottomless 55-gallon drums welded together into which workers dumped highly radioactive wastes.
The VPUs were buried upright in the ground. They are expected to contain the site's most radioactive waste. Planning is under way for safely removing the VPUs and their contents.
Darby said it will take about 18 months to complete excavation of the trenches and load out the debris. Most of the waste removed from the site will be transported to Hanford's Environmental Restoration Disposal Facility for disposal.
The 618-10 Burial Ground is located about six miles north of the city of Richland and a few hundred yards from the Hanford Site's main highway. It is also located about four miles west of the Columbia River.
The burial ground was opened in March 1954 and accepted waste until it closed in September 1963.
Disposal records from the 1950s and 1960s are incomplete, but the burial ground is thought to contain radiologically contaminated laboratory instruments, bottles, boxes, filters, aluminum cuttings, irradiated fuel element samples, metallurgical samples, electrical equipment, lighting fixtures, barrels, laboratory equipment and hoods, and high-dose-rate wastes in shielded, or concreted, drums.
Washington Closure manages the $2.3 billion River Corridor Closure Project, known as the largest environmental cleanup closure project in the nation, for the DOE Richland Operations Office.