Since the High Flux Beam Reactor (HFBR) was shut down in 1997 and permanently closed in 1999, many actions have been taken to partially decommission and prepare the HFBR for safe storage. Final decommissioning of the HFBR building will be performed at the completion of the decay period. The actions undertaken throughout the HFBR complex ensure that it remains in a safe and stable condition and prepared it for long-term surveillance and maintenance and decommissioning.
The stabilization and partial decommissioning of the HFBR was conducted under the federal Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). In 1992, an Interagency Agreement (PDF) among the DOE, the U.S. Environmental Protection Agency (EPA) and the New York State Department of Environmental Conservation (NYSDEC) became effective. The IAG provided the overall framework for conducting environmental restoration activities at BNL.
The selected remedial alternative is documented in the HFBR Record of Decision (PDF) which was approved by the DOE and EPA with the concurrence of the NYSDEC, the New York State Department of Health (NYSDOH), and the Suffolk County Department of Health Services (SCDHS) in February, 2009. The selected remedy included phased Decontamination and Dismantlement (D&D) with near-term control rod blade removal.
The final remedy for the HFBR incorporated many cleanup actions, including: removal and disposal of HFBR fuel and primary coolant; shipment of equipment for reuse at other facilities; cleanup and transfer of the Cold Neutron Facility for reuse; dismantling of many ancillary buildings in the HFBR complex; cleanup of the Waste Loading Area; removal of contaminated underground utilities and piping; removal and disposal of the reactor control rod blades and beam plugs; and preparation of the confinement building for safe storage. The remedy also includes a number of near-term actions to be completed by 2020, including dismantling of the HFBR Stack and associated components.
The segmentation, removal, and disposal of the remaining HFBR structures, systems and components (reactor vessel, thermal shield, biological shield, and others) after a safe storage decay period (not to exceed 65 years) are also part of the final remedy. The decay period allows for the natural reduction of the high radiation dose rates to a point where conventional demolition techniques can be used for the dismantling of the large activated components.
The actions undertaken to stabilize and secure the HFBR included removing contaminated structures, hazardous materials, and radioactively contaminated equipment and components to deactivate and stabilize the facility in preparation for decommissioning and dismantling. The actions taken included:
Extensive groundwater characterization was conducted between 1997 and 1999 to determine the extent of the tritium contamination. The leak was confined to Lab property and both the U.S. EPA and SCDHS agreed that it posed no threat to BNL employees or to public health, nor did it affect any drinking water supplies.
The pump-and-recharge system was installed in 1997 and operated until 2000. Installed near the southern edge of the 2,200 foot-long plume, the system was designed to remove the groundwater containing tritium from the aquifer and pump it to a recharge basin further north. There, the water was allowed to re-enter the aquifer. Groundwater monitoring showed that this system was effective in halting the southward migration of the tritium plume at a point approximately 3,500 feet north of the site boundary. It ensured that any tritium in the groundwater would be below drinking water standards before it reached the Lab boundary. The system was turned off in September 2000 and placed in stand-by mode since groundwater data indicated that the plume was not growing.
Additional groundwater remediation was conducted at the HFBR in 2000 and 2001, when a low-flow pumping system extracted the highest levels of tritium from the groundwater near the reactor. A total of approximately 90,000 gallons of water were removed from the aquifer and disposed of off the Lab site.
Monitoring of the HFBR groundwater contamination has continued in accordance with the Operable Unit III Record of Decision (PDF) which details the selected remedial actions for areas of groundwater contamination at BNL. In November 2006, groundwater triggers for tritium were reached and it was recommended that the pump-and-recharge system be restarted and an additional extraction well was installed in 2007.
The current status of the groundwater contamination is discusses in the annual Groundwater Status Reports.