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| During a regularly scheduled meeting between Brookhaven National Laboratory, U.S. Department of Energy, U.S. Environmental Protection Agency, New York State Dept. of Environmental Conservation and Suffolk County Dept. of Health Services, the results of the latest tritium plume sampling were discussed. |
Tritium plume measurements continue
Samples taken immediately south of the Lab's High Flux Beam Reactor (HFBR), as part of a planned investigation to further define the tritium plume, contain higher tritium levels than previously seen in that area. The highest levels measured are approximately 2.5 times higher than the 2 million picoCuries per liter reported at the public meeting on the groundwater cleanup in March. Regulatory agencies have been briefed on the most recent results.
Even at the higher concentrations that have been detected near the HFBR, tritium is not expected to reach the site boundary at levels above drinking water standards.
The higher concentrations of tritium are not unexpected, considering the high levels that are known to have been in the HFBR spent fuel storage pool. The Lab will continue to work with the U.S. Department of Energy (DOE) and the regulatory agencies to make a final decision on how to remediate the tritium plume.
Sampling methods and future actions
The increased tritium levels were detected in temporary groundwater monitoring wells. These wells are one-time drillings used to sample groundwater at a variety of depths in one location. The well location is filled in with soil after all samples are taken. While awaiting regulatory agency concurrence on the final groundwater cleanup plan, the Lab and DOE took these samples near the HFBR to get a more detailed "picture" of the tritium plume and plan the placement of permanent wells.
Based on these results, and as part of the final cleanup remedy, the Lab will be installing additional permanent wells in the vicinity of the HFBR. If tritium levels measured in these permanent wells are above a "trigger" level agreed to with the regulatory agencies, the higher concentrations of tritium will be pumped from the ground and shipped to a licensed off-site facility for disposal.
Dilution and radioactive decay will reduce tritium levels as the groundwater moves southward. Pumping out the higher levels of tritium would further ensure that the tritium levels will not exceed standards at or beyond the Lab's southern boundary.
Lab to release report on localized soil cleanup
On September 20, Brookhaven National Laboratory expects to release a report on cleanup alternatives for contaminated soils at the Brookhaven Linac Isotope Producer, or BLIP, for public comment. The BLIP Engineering Evaluation/Cost Analysis summarizes the nature and extent of soil contamination, describes and evaluates the removal alternatives, and recommends one alternative.
The alternatives include: maintenance or upgrade of an existing cap, in-place containment of soils using a cement or colloidal silica grout, and excavation of the contaminated soils.
The recommended alternative is upgrade of the existing cap and in-place containment by injecting a colloidal silica grout, pending results of grout performance testing that is currently underway. If this testing indicates that the silica grout would not meet performance goals, then the cap upgrade alone will be recommended.
The BLIP Engineering Evaluation/Cost Analysis will be available in local libraries as part of the Lab's Administrative Record. The Executive Summary will also be available on the ERD web site at http://www.oer.dir.bnl.gov/blipeeca.html.
Following the 30-day public comment period, all comments will be reviewed and considered. The selected alternative will be documented in an Action Memorandum, which will be made available to the public later this year.