ORAU lab flooded with groundwater samples after leaks discovered at nuclear power plants
Samples have begun to pour in to the radiochemistry laboratory of Oak Ridge Associated Universities' (ORAU) Independent Environmental Assessment and Verification program. The discovery of heightened levels of tritium in groundwater surrounding several of the nation’s nuclear power plants has triggered an investigation by the Nuclear Regulatory Commission (NRC) into reports of leaks at aging facilities across the country.
Predominantly known for its independent verification and health physics capabilities, ORAU operates a radiochemistry laboratory that the NRC solely relies on to carry out its radioanalytical evaluations. Though the lab most often performs analysis of unique soil matrices, the arrival of groundwater samples has become top priority for ORAU’s chemists. Since October 2005, the lab has received more than 450 groundwater samples from nuclear power plants in Indian Point, N.Y., Braidwood, Byron, and Dresden, Ill., and Palo Verde, Ariz., and continues to receive additional samples every other week. Samples from a sixth plant in Callaway, Mo., are also expected to arrive soon.
Lab personnel have primarily tested samples for elevated levels of tritium, a radioactive isotope of the element hydrogen. Tritium naturally occurs in the environment in very low concentrations and is a byproduct of electricity-producing nuclear reactors. It is commonly released into the atmosphere by nuclear facilities in the form of steam or leaks into nearby soil and groundwater. Because these releases are usually small and follow federal guidelines, it is common for low levels of tritium to make their way to drinking water supplies via atmospheric and groundwater movement.
The Environmental Protection Agency considers tritium readings of 20,000 picocuries (a unit of radiation) or less per liter safe for human consumption. However, some of the samples have produced readings as much as 10 times greater than the EPA’s limit—enough to gain the attention of the NRC, public interest groups, politicians, local residents and national media.
Despite being considered one of the least dangerous radionuclides because it emits very weak radiation, exposure to extreme levels of tritium can result in increased health risks, including cancer. The NRC will use ORAU’s findings as it meets with plant officials to address ways to prevent future leaks.