Upton, NY - In a memo issued to employees on January 17, the U.S. Department of Energy's Brookhaven National Laboratory notified staff that routine monitoring by BNL recently found tritium in the groundwater in the center of the BNL site, just south of one of the Lab's two research reactors. The measured concentration was about two-and-a-half times the New York State Drinking Water Standard.
On-site drinking water is not contaminated with tritium, nor is it in any danger of being contaminated. Potable supply wells are located north of the tritium contamination, in the opposite direction of groundwater flow. Also, each supply well is checked quarterly for all contaminants, including radioactivity, and water from the tap is tested daily for radioactivity. BNL's employees were assured in the memo that the Lab's potable water is safe to drink.
Groundwater flow is to the south, and the Lab's southern border is about 1.5 miles away from the location of the tritium contamination. It would take more than 20 years for contamination from the center of the site to travel beyond the southern boundary. Tritium has never been detected above the Drinking Water Standard in monitoring wells at BNL's southern boundary, in the path of groundwater flow from the location of this tritium contamination.
The Department of Energy and the Lab are investigating the contamination and will take action as appropriate to ensure that the contamination stays within the site boundary.
Tritium is a radioactive isotope of hydrogen. It has a half-life of 12 years, that is, starting with a known quantity, half of it decays into nonradioactive helium in 12 years.
The tritium was found in two monitoring wells recently installednear the High Flux Beam Reactor. They were sampled in October and December of 1996 and several times this January. The concentrations increased significantly between October and now. Only one of the wells exceeds the Drinking Water Standard.
The source of the tritium is not known at this time. It is clear, however, that the reactor vessel itself is not the source, since sensitive leak detectors positioned around the vessel have not detected any leaks.
County, state and federal officials have been notified, and Brookhaven Lab and DOE are working aggressively to determine both the source and the extent of the tritium contamination. Over the next few weeks, the Lab will be investigating potential sources of the tritium and drilling additional monitoring wells as part of that investigation. The Lab will coordinate with state and federal regulators in all major steps of the investigation.
The HFBR had been shut down in December for routine maintenance and will remain shut down until the situation is satisfactorily understood by both DOE and BNL.