Document Type

Technical Report

Publication Date



The objective of this task is to determine the principal oxidation state (redox) species of select elements in samples of groundwater in the vicinity of Yucca Mountain (YM), which is being evaluated as a site for geologic storage of the nation’s spent nuclear fuel and high-level nuclear waste. Samples to be analyzed include, but are not limited to, groundwater from wells of the Nye County Early Warning Drilling Program. Elements to be studied include arsenic (As), antimony (Sb), selenium (Se), chromium (Cr), manganese (Mn), iron (Fe), copper (Cu), molybdenum (Mo), vanadium (V), tungsten (W), rhenium (Re), and uranium (U). The purpose is to develop a more accurate and complete description of the redox properties of YM-related groundwater, which influences the solubility and consequently the transport of radionuclides. Indeed, a possible natural barrier to radionuclide migration in the saturated zone (SZ) is the presence of non-oxidizing or reducing environments. For example, the mobility of Tc-99 in oxic groundwater, ascribed to the pertechnetate ion, is greatly diminished in reducing groundwater. The containment of radionuclides away from the accessible environment is a key feature in the Yucca Mountain performance assessment.


Ground water – Pollution; Nevada – Yucca Mountain; Oxidation-reduction reaction; Radioactive waste repositories; Radioisotopes


Chemistry | Environmental Chemistry | Hydrology | Radiochemistry




Report Document Identifier: SIP-UNLV -048

Task LBL-ST-01

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