Preliminary testing near a former University of California, Davis, low-level radiation research facility shows trace levels of a radioactive material in shallow groundwater south of the 15-acre site, according to an environmental consulting company hired by UC Davis. The company has reported finding tritium -- a radioactive form of hydrogen commonly used in laboratory tests -- while using a relatively new technology to scout for groundwater contamination as part of ongoing environmental assessment and cleanup of the former Laboratory for Energy-Related Health Research. The tritium, identified but not confirmed at two test spots on private property roughly 1,500 feet from the edge of the rural LEHR site, was in concentrations well within acceptable levels set by drinking water standards and poses no health threat to the public. Drinking water for UC Davis and the city of Davis comes from deep wells far from the area. However, campus officials have asked the state Department of Health Services to perform additional testing to confirm the findings. "The information we have at this point is very preliminary. We need to take and examine more samples to determine whether a problem exists and to ensure that no error has been made in the handling or analysis of these two samples," said Carolyn Owen, the radiation safety officer and assistant director of environmental health and safety at UC Davis. The tritium is reported in data collected for UC Davis by the Sacramento office of the environmental consulting firm Dames & Moore. Using a relatively new technology called hydropunching to screen for potential test well sites, workers performed 25 hydropunch tests (generally 75 feet to 95 feet deep) in locations around the border of the LEHR site. The results are the first indication that radioactive material in higher than naturally occurring concentrations may be in groundwater off the campus property. -more- 2-2-2 LEHR Groundwater Levels of tritium higher than the natural background levels of 100 picocuries to 200 picocuries per liter -- but well below the 20,000 picocuries set as the drinking water limit -- were found in three areas. In two spots 1,500 feet from the site's southern edge, two water samples showed tritium concentrations of 1,517 picocuries and 930 picocuries. Several hundred feet northeast of the site, on campus property, a water sample showed 2,220 picocuries. Due to the nature of the tests, the three sample measurements could be in error by as much as 50 percent. UC Davis and the U.S. Department of Energy are in the midst of a multiyear assessment and cleanup of the LEHR site, where for more than 30 years DOE-funded scientists studied the health effects of exposure to low levels of radiation. The property is also the site of an inactive campus sanitary landfill, closed in 1966, and several inactive disposal sites for low-level radioactive wastes, which the campus and LEHR used until 1974, according to regulations. Extensive soil and groundwater testing has been under way for more than four years at the site, located a mile south of the main UC Davis campus. Since 1988, the campus has reported finding elevated levels of nitrates, the trace metal hexavalent chromium, tritium, carbon 14 and organic chemicals in test wells on the LEHR site. Quarterly testing of domestic wells on nearby private property since 1989 has shown elevated levels of nitrates and chromium, whose source is unclear. The campus has been supplying these neighbors with drinking water since 1989. If additional tests confirm that tritium has migrated in groundwater from the LEHR property, a possible source is the campus's inactive low-level radioactive waste disposal sites, according to Owen. She said it is doubtful that the tritium came from past research activities at the LEHR site itself, since LEHR research involved the use of different radioactive materials, strontium and radium. Working with the Regional Water Quality Control Board and state Department of Health Services, the campus will continue conducting tests to identify and map any groundwater contamination from the inactive landfill and disposal sites, according to Owen. The assessment is expected to be completed by the end of 1992.