Brookhaven National Laboratory (BNL) is continuing to make progress in removing contaminated soils from the Lab site. That progress will accelerate even more as the Operable Unit I (OU I) cleanup of on-site soils proceeds this year. The OU I accomplishments to date and upcoming actions are detailed below.
The U.S. Department of Energy and the Laboratory are committed to minimizing waste generation and shipment during the OU I project. By employing advanced cleanup technologies, as described below, BNL can reduce the volume of waste while still meeting our cleanup goals.
Progress to date
Since last November, more than 1,600 cubic yards of soils have been loaded into railcars and transported to a licensed disposal facility in Utah. BNL excavated these soils from the Chemical Holes 55 pits on the Laboratory site where chemical containers, glassware and other debris were buried between the 1950s and early 1980s. After the excavation, debris from the pits was sorted and packaged, and the soils were stockpiled for later disposal.
Four soil stockpiles and some non-hazardous debris have been disposed of. Twelve additional stockpiles and some packaged debris remain to be shipped. All material should be disposed of by the end of 2001.
This spring, ten 55-gallon drums of soils from the Chemical Holes were treated to remove mercury. These soils also contained low levels of radioactive materials, and would have required more difficult and costly disposal as "mixed waste" without treatment. Removing the mercury allowed the Lab to dispose of the mercury and soils separately, the first as hazardous waste and the second as radioactive waste.
In the fall of 1999, 70 cubic yards of sludge (over 14,000 gallons) were removed from six out-of-service underground storage tanks at the Lab's Waste Concentration Facility (Building 811). The sludge was solidified and packaged, and will be shipped off site for disposal in the near future. The tanks and surrounding soils are scheduled for removal in 2001.
Future actions
In April 2000, BNL began excavating isolated areas of landscaping soils on site. About 1,400 cubic yards of soils containing low levels of cesium-137 will be excavated from twelve separate areas. This excavation will affect a total of less than an acre of land.
The excavated soils will be sorted by the innovative "segmented gate system." In this system, soils are carried along a conveyor belt and scanned to determine the level of contamination in small volumes of the soil. The system then quickly and easily separates soils with radioactive materials above cleanup goals from soils below cleanup goals. This is expected to greatly reduce the volume of soil that must be shipped off site for disposal and the ensuing disposal costs.
Dust control methods are an important feature of the project plans. The community has voiced concerns about contaminants in the soil becoming airborne. Several dust control methods will be employed, such as spraying the soil with water during excavation and sorting, and suspending work during periods of high wind. Additionally, the Lab will conduct air monitoring during excavation and packaging activities.
The Operable Unit I cleanup will encompass several additional on-site areas in the future, including the Lab's former hazardous waste management facility. BNL will provide updates as work proceeds.