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Graphs showing relations between mean ecosystem elevations and mean annual precipitation and actual evapotranspiration, and potential evapotranspiration and climatic water deficit, Spring Mountains and Sheep Range, Clark County, Nevada ......20 climatic water deficit is the best predictor of ecosystem distribution (R 2 = 0.92). Computed water balances indicate that substantially more recharge is generated in the Spring Mountains than in the Sheep Range. A geospatial database containing compiled and developed hydroclimatic data and other pertinent information accompanies this report.

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS.For an overview of USGS information products, including maps, imagery, and publications, visit http://store.usgs.gov/.Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.Suggested citation: Garcia, C.A., Jackson, T.R., Halford, K.J., Sweetkind, D.S., Damar, N.A., Fenelon, J.M., and Reiner, S.R., 2017, Hydraulic characterization of volcanic rocks in Pahute Mesa using an Integrated Analysis of 16 multiple-well aquifer tests, Nevada National Security Site, 2009-14: U.S. Geological Survey Scientific Investigations Report 2016-5151, 62 p., https://doi.org/10.3133/sir20165151. ISSN 2328-0328 (online) iii AcknowledgmentsThis report was made possible by funding from the U.S. Department of Energy under Interagency Agreement DE-NA0001654 with the Department of Energy, National Nuclear Security Administration.The authors gratefully acknowledge the U.S. Department of Energy (DOE), Navarro Nevada Environmental Services, LLC., Navarro-Intera, LLC, and Navarro for providing aquifer test data at pumping wells, long-term water-level monitoring data at observation and background wells, and the draft Phase II hydrostratigraphic framework model; Jeffery Wurtz and Daniel Neubauer of Navarro and Jeffery Sanchez of Navarro-Intera, LLC, for data collection and data processing; and Peter Martian of Navarro and Rishi Parashar of the Desert Research Institute for helpful review comments.The authors also gratefully acknowledge Terry L. Miller, Glenn L. Locke, and Gary L. Otto, retired, for data collection and data processing and Shana L. Mashburn and Marshall W. Gannett, all of the U.S. Geological Survey, for helpful review comments. Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83).Elevation, as used in this report, refers to distance above the vertical datum. Supplemental Information AbstractAn improved understanding of groundwater flow and radionuclide migration downgradient from underground nuclear-testing areas at Pahute Mesa, Nevada National Security Site, requires accurate subsurface hydraulic characterization. To improve conceptual models of flow and transport in the complex hydrogeologic system beneath Pahute Mesa, the U.S. Geological Survey characterized bulk hydraulic properties of volcanic rocks using an integrated analysis of 16 multiple-well aquifer tests. Single-well aquifer-test analyses provided transmissivity estimates at pumped wells. Transmissivity estimates ranged from less than 1 to about 100,000 square feet per day in Pahute Mesa and the vicinity. Drawdown from multiple-wel...

The U.S. Geological Survey, in cooperation with the Nevada Department of Conservation and Natural Resources-Division of Water Resources and the Las Vegas Valley Water District, compiled 44 individual interferograms and 1 stacked interferogram comprising 29 satellite synthetic aperture radar acquisitions of Las Vegas Valley, Nevada, from 1992 to 1999. The interferograms, which depict short-term, seasonal, and long-term trends in land subsidence and uplift, are viewable with an interactive map. The interferograms show that land subsidence and uplift generally occur in localized areas, are responsive to groundwater pumpage and artificial recharge, and, in part, are fault controlled. Information from these interferograms can be used by water and land managers to mitigate land subsidence and associated damage. Land subsidence attributed to groundwater pumpage has been documented in Las Vegas Valley since the 1940s. Damage to roads, buildings, and other engineered structures has been associated with this land subsidence. Land uplift attributed to artificial recharge and reduced pumping has been documented since the 1990s. Measuring these land-surface changes with traditional benchmark and Global Positioning System surveys can be costly and time consuming, and results typically are spatially and temporally sparse. Interferograms are relatively inexpensive and provide temporal and spatial resolutions previously not achievable. The interferograms are viewable with an interactive map. Landsat images from 1993 and 2000 are viewable for frames of reference to locate areas of interest and help determine land use. A stacked interferogram for 1992-99 is viewable to visualize the cumulative vertical displacement for the period represented by the individual interferograms. The interactive map enables users to identify and estimate the magnitude of vertical displacement, visually analyze deformation trends, and view interferograms and Landsat images side by side. The interferograms and Landsat images are available for download, in formats for use with Geographic Information System software.

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS.For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit