Physical Sciences and Mathematics Commons^™

Assessing Near Surface Hydrologic Processes And Plant Response Over A 1600 M Mountain Valley Gradient In The Great Basin, Nv, U.S.A., Dale Devitt, Brian Bird, Brad Lyles, Lynn Fenstermaker, Richard Jasoni, Scotty Strachan, Jay Arnone Iii, Franco Biondi, Scott Mensing, Laurel Saito

Life Sciences Faculty Research

This study investigated near surface hydrologic processes and plant response over a 1600 m mountain-valley gradient located in the Great Basin of North America (Nevada, U.S.A.) as part of a long-term climate assessment study. The goal was to assess shifts in precipitation, soil water status and associated drainage with elevation and how this influenced evapotranspiration and plant cover/health estimated by a satellite-derived Normalized Difference Vegetation Index (NDVI), all to better understand how water is partitioned in a mountain valley system. Data were acquired during a three-year period from meteorological stations located in five plant communities ranging in elevation from 1756 …

Groundwater Characterization At Yucca Mountain Task 2: Surface Complexation And Solid Phase Sorption, Kenneth Czerwinski, Anthony Hechanova, Amy J. Smiecinski

Publications (YM)

The purpose and scope of this report is to present an overview of the experiments, methods, results, and conclusions from research performed for the project “Groundwater Characterization at Yucca Mountain Task 2: Surface Complexation and Solid Phase Dissolution”. The impact of surface complexation, alteration phase formation, and solution competition with metal ions on the solubility and speciation of actinide elements (U, Pu, Np) will be examined. In particular the role of iron (as Fe2+ and Fe3+) and silicate (as SO3 2-) concentrations on speciation, solubility, sorption, and secondary phase formation of actinides will be investigated. While a large body of …

Geostatistical And Stochastic Study Of Radio Nuclide Transport In The Unsaturated Zone At Yucca Mountain, Ming Ye, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The U.S. Nuclear Waste Technical Review Board [Cohon et al. 1998] evaluated the technical and scientific validity of activities undertaken by the Secretary of Energy to characterize Yucca Mountain, Nevada, for its suitability as an underground repository in which to store high-level radioactive waste and spent nuclear fuel. In the report, the Board pinpointed that the study on groundwater flow and radionuclide transport in the saturated and unsaturated zones below Yucca Mountain should, over the next several years, focus on reducing prediction uncertainty. In its 2002, the Board repeated this concern by stating, “… hydrogeologic processes that affect radionuclide transport …

Yucca Mountain Saturated Zone Carbon-14, James Thomas, Drew Coleman, Raymond E. Keeler, Amy J. Smiecinski

Publications (YM)

This Scientific Investigation Plan (SIP) provides an overview of the work described in “Yucca Mountain Saturated Zone Carbon-14”, a proposal funded by the U.S. Department of Energy’s (DOE) Office of Repository Development under the UCCSN/YMP Co-op in support of the Science and Technology Initiatives. The objective of this work is to provide improved estimates of the time required for ground water to travel from the site of the proposed high-level radioactive waste repository at Yucca Mountain, Nevada, to the accessible environment.

Chemical Analyses In Support Of Yucca Mountain Studies, Jeanette Daniels, Klaus J. Stetzenbach, Drew Coleman, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The objective of this task “Chemical Analyses in Support of Yucca Mountain Studies” is to provide the Department of Energy (DOE) with data and reports from comprehensive chemical analyses of waters sampled from the wells of the Nye County Early Warning Drilling Program (NCEWDP), the Inyo County’s Drilling Program, and the Nye county Tracer Test. In addition, this task will be used to provide other laboratory support needs as they arise within the Yucca Mountain Project. This support is provided by the Harry Reid Center for Environmental Studies (HRC) at University of Nevada, Las Vegas (UNLV), which is part of …

Groundwater Flow And Thermal Modeling To Support A Preferred Conceptual Model For The Large Hydraulic Gradient North Of Yucca Mountain, Phil Oberlander, Greg Pohll, Drew Coleman, Raymond E. Keeler, Amy J. Smiecinski

Publications (YM)

This task will create a two-dimensional, saturated zone, vertical cross-section model of groundwater flow and thermal transport through the large hydraulic gradient (LHG). This model is referenced herein as the thermal model. The scope of this study is limited to presenting a postulated hydrogeologic configuration of the LHG. The conceptualization will include the use of postulated hydrogeologic structures and material properties. The thermal model will be spatially limited to the area immediately upgradient and downgradient of the LHG and will not reproduce the many hydrogeologic features of the existing regional and site-scale models. The thermal model will be orientated north …

Yucca Mountain Climate Technical Support Representative, Saxon E. Sharpe, Dick Reinhardt, Eric Smistad, Don Baepler, Amy J. Smiecinski

Publications (YM)

The principal investigator (PI), Saxon Sharpe, for Task ORD-FY04-012, DOE Cooperative Agreement DE-FC28-04RW12232, will serve as Yucca Mountain Climate Technical Support Representative for the Department of Energy (DOE) in a series of activities related to past, present, and future climate for the Yucca Mountain Project (YMP) climate program.

As stated in the Viability Assessment of a Repository at Yucca Mountain: “Climate and its changes over time directly affect system performance at Yucca Mountain.” Currently, information from climate studies is used in models that support the Total System Performance Assessment and Licensing Application. It is a model component of all key …

Estimation Of Groundwater Velocities From Yucca Flat To The Amargosa Desert Using Geochemistry And Environmental Isotopes, Ronald L. Hershey, Steve Y. Acheampong

Publications (WR)

Geochemical modeling techniques were applied to groundwater flowpaths from Yucca Flat on the Nevada Test Site (NTS) to the Amargosa Desert, south of the NTS to estimate groundwater flow velocities for independent comparison to velocities calculated by other methods. The groundwater flowpaths examined considered flow in the carbonate aquifer beneath Yucca and Frenchman flats mixing with flow from carbonate aquifers east and southeast of the NTS and discharging at wells south of the NTS border. The approach used the computer codes WATEQ4F and NETPATH to calculate chemical speciation, determine the saturation state of mineral phases, and simulate mixing and the …

An Isotopic Analysis Of The Hydrology And Riparian Vegetation Water Sources On Bishop Creek, M. L. Space, J. W. Hess, S. D. Smith

Life Sciences Faculty Research

Five power generation plants along an eleven kilometer stretch divert Bishop Creek water for hydro-electric power. Stream diversion may be adversely affecting the riparian vegetation. Stable isotopic analysis is employed to determine surface water/ground-water interactions along the creek. surface water originates primarily from three headwater lakes. Discharge into Bishop Creek below the headwaters is primarily derived from ground water. The average δD and δ18O values are significantly different for surface water and ground water that an isotopic analysis can delineate between these two components of flow. Therefore isotopic shifts along the creek can determine gaining reaches. In addition, by knowing …

Investigations And Research In Nevada By The Water Resources Division, U. S. Geological Survey, 1982-83, Terry Katzer, Otto Moosburner, William D. Nichols

Publications (WR)

The Water Resources Division, U.S. Geological Survey, is charged with (1) maintaining a hydrologic network in Nevada that provides information on the status of the State's water resources and (2) engaging in technical water-resources investigations that have a high degree of transferability. To meet these broad objections, 26 projects were active in Nevada during fiscal year 1982 in cooperation with 36 Federal, State, and local agencies. Total funds were $3,319,455, of which State and local cooperative funding amounted to $741,500 and Federal funding (comprised of Geological Survey Federal and cooperative programs plus funds from six other Federal agencies) amounted to …

Available Water Supply Of The Las Vegas Ground-Water Basin Nevada, Glenn Thomas Malmberg

Publications (WR)

The Las Vegas ground-water basin as described in this report includes the southern part of Indian Spring Valley, Three Lakes Valley, the northern half of Ivanpah Valley, and Las Vegas Valley. These valleys in part are inferred to form a hydrologic unit that includes an area of about 3,000 square miles in the southern part of Clark County, Nev.

The valleys forming the Las Vegas ground-water basin are broad structural depressions surrounded by mountains. The climate of the region is arid, and precipitation in the basin lowlands rarely exceeds 5 inches per year. Drainage is interior except for occasional Hood …

Interbasin Movement Of Ground Water At The Nevada Test Site, Isaac J. Winograd

Publications (WR)

The present paper presents hydraulic evidence for the interbasin circulation of ground water through carbonate rocks of Paleozoic age at the Nevada Test Site. An integral part of this evidence is the discovery that aquifers in alluvium and tuff, formerly thought to be the principal aquifers at the Test Site, are semiperched above a thick tuffaceous aquiclude that separates them from the carbonate rocks.

This paper is based on one of the studies being made by the Geological
Survey for the Atomic Energy Commission. These studies seek to evaluate
the risk that may arise if ground water should be contaminated …

Water Levels And Artesian Pressure In Wells In Las Vegas Valley And In Other Valleys In Nevada, 1913-1945, T. W. Robinson, George B. Maxey, J. C. Fredericks, C. Harry Jameson

Publications (WR)

The rock formations of the earth are great natural reservoirs in which a part of the water derived from rain and snow is stored. Water levels and artesian pressure in wells register the stages of these natural reservoirs. The changes in water levels or artesian pressure are indicative of the depletion or replenishment of the natural reservoirs. Systematic and periodic measurements of water levels and artesian pressure in wells have been made in Nevada, by State and Federal agencies from time to time. However, only a few of these measurements have ever been published. Under the cooperative arrangement between the …

Progress Report On The Ground-Water Resources Of The Las Vegas Artesian Basin, Nevada, George B. Maxey, C. Harry Jameson

Publications (WR)

Whether the tremendously increased population acquired by Las Vegas in the years 1940 to 1942 will be retained cannot at present be foretold. However, the valley will undoubtedly be expected to support a considerably larger population than it did at any time prior to 1940, and continually increasing demands on the water supply for innumerable pcacetimc activities must be anticipated. Therefore, a sound evaluation of tho ground water resources of Las Vegas Valley is directly in line with the other wisely progressive planning programs which are now operating or are taking shape in the valley as well as in the …