title: Surveillance monitoring of soils for radioactivity: Lawrence Livermore National Laboratory 1976 to 1992.
abstract: Environmental monitoring of soils at the U.S. Department of Energy's Lawrence Livermore National Laboratory in California has been conducted for more than 20 years. The purposes of the program are to determine the effects, if any, of LLNL's operations on the surrounding areas near its two separate sites and to determine if there are any long-term trends. Data from 1976 to 1992 were analyzed to determine their appropriate statistical distribution, and differences among locations and changes with time were evaluated. The data generally followed lognormal distributions, and results for 239 + 240Pu and 137Cs data were consistent with previously reported values for world-wide fallout. Although all values for 239 + 240Pu were small, 239 + 240Pu data for locations downwind from the Livermore site were found to be statistically significantly higher than for upwind locations. Results for 238U at Site 300 locations near where 238U is used were significantly higher than background locations. Results for 137Cs and 40K were not significantly different between sites, whereas results for 232Th were significantly higher for Site 300 than for the Livermore site. Doses for all radionuclides were below acceptable levels, and doses for most radionuclides were negligible. Evaluation of trends with time yielded small or statistically insignificant changes for all radionuclides.
authors.affiliation: Environmental Monitoring Section, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
authors.forename: G
authors.initials: G
authors.lastname: Gallegos
mesh_terms: D002588:Cesium Radioisotopes / Q000032:analysis; D004784:Environmental Monitoring; D011005:Plutonium / Q000032:analysis; D011829:Radiation Dosage; D012990:Soil Pollutants, Radioactive / Q000032:analysis*; D013997:Time Factors; D014501:Uranium / Q000032:analysis
chemical_list: D002588:Cesium Radioisotopes; D012990:Soil Pollutants, Radioactive; D014501:Uranium; D011005:Plutonium