DOE OSTI2016
This report is an update of report LA-13859-MS (Bowen et al., 2001). In that original report, the underground radionuclide inventory at the Nevada National Security Site (NNSS) was decay corrected to September 23, 1992, the date of the last underground nuclear test at the NNSS. In this report, the inventory is updated to account for the decay of radionuclides over two additional decades (1992-2012) and revised tritium, fission product and actinide inventory figures and tables are presented. The maximum contaminant levels for radionuclides were also updated to Safe Drinking Water Act Maximum Contaminant Levels (MCLs) (CFR, 2013). Also, a number of minor errata found in the original publication were corrected. An inventory of radionuclides produced by 828 underground nuclear tests conducted at the NNSS by the Lawrence Livermore National Laboratory, the Los Alamos National Laboratory, and the Department of the Defense from 1951 to 1992 includes tritium, fission products, actinides, and activation products. The inventory presented in this report provides an estimate of radioactivity remaining underground at the NNSS after nuclear testing. The original test inventory is decayed to September 30, 2012, and predictions of inventory decay over the subsequent 1000 years are presented. For the purposes of summary and publication, the Los Alamos National Laboratory and Lawrence Livermore National Laboratory authors of this report subdivided the inventory into five areas corresponding to the principal geographic test centers at the NNSS. The five areas roughly correspond to Underground Test Area “Corrective Action Units” (CAUs) for remediation of groundwater. In addition, the inventory is further subdivided for the Yucca Flat region by tests where the working point depth is more than 328 feet (100 meters) above the water table and tests that were detonated below that level. Water levels used were those from the U. S. Department of Energy, Nevada Operations Office (1997), now called the Nevada Field Office. Curie activities and atoms are reported as of September 30, 2012. This inventory is strictly a compilation of the residual radiologic inventory remaining from the underground nuclear tests conducted by Lawrence Livermore National Laboratory, Los Alamos National Laboratory and the Department of the Defense from 1951 to 1992 and does not include radioactivity from other types of nuclear testing (e.g., atmospheric, reactors, rocket engines). A companion classified report (Miller et al., 2002) contains test-specific data for each test performed at the NNSS. This work has been sponsored by the U. S. Department of Energy, National Nuclear Security Administration Nevada Field Office.
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗