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| The landscape soils excavations began in May and were completed in August. Here, Project Manager Jim Brower (far right) and Field Engineer Tom Doyle (far left) review the day's plans as Christine Lafon (ERD) and Steve Townsend (Radiological Control Division) look on. |
Since this spring, the Environmental Restoration Division (ERD) has made visible progress in cleaning up contaminated soils on Lab property. Landscape soils containing low levels of radioactive cesium have been excavated from several areas and transported off-site to a licensed disposal facility in Utah.
Key step taken
The project marks the first soil cleanup to begin after the Operable Unit I Record of Decision was approved last fall. It is also significant because it removes a source of possible cesium exposure to deer and other wildlife. Although the state Department of Health has assured residents that there is little health risk from consuming deer hunted in areas surrounding the Laboratory (hunting is not allowed on the site), removing this cesium source is an important part of Brookhaven's commitment to protecting the environment.
"The excavation of these landscape soils is a key first step in our soil remediation project," stated ERD manager John Meersman. "We are encouraged by the progress we have made, and look forward to completing the balance of this important project."
This project involved the removal of over 2,500 cubic yards of contaminated soil, or enough to fill 40 railcars. Now that all the excavations are complete, an independent sampling team from the Oak Ridge Institute for Science and Education will verify that all soil containing cesium levels above cleanup goals has been removed. Then, the excavated areas will be filled with clean soil and reseeded. This process is expected to be completed by the end of September.
New technology tested
The Department of Energy and the Laboratory are committed to using emerging technologies whenever possible. For this project, a "segmented gate system" was tested for soil sorting. This system separated contaminated soils from clean soils, and, if successful, would have reduced the volume of soil for disposal and associated disposal costs.
Unfortunately, this system was less effective than anticipated. Frequent rain rendered the excavated soils clumpier than expected and more difficult to sort. Of the 625 cubic yards of soil processed by the system, only 95 cubic yards tested clean due to mixing during the excavation process. In addition, the overall sorting process was not as efficient as expected, leading to reduced cost savings.
The segmented gate system trial demonstrates the challenges in implementing
these innovative solutions. Nevertheless, DOE and BNL will continue to both
test new technologies that are compatible with local site conditions and
strive to improve remediation efficiency.