{
  "accessLevel": "public",
  "bureauCode": [
    "010:12"
  ],
  "contactPoint": {
    "@type": "vcard:Contact",
    "fn": "Nevada Water Science Center",
    "hasEmail": "mailto:GS-W-NVcrs_Webmaster@usgs.gov"
  },
  "description": "Three-dimensional numerical models were used to determine the permeable pathways \nbetween the HANDLEY underground nuclear test and downgradient boreholes ER-20-12 \nand PM-3, Pahute Mesa, southern Nevada. The SEAWAT code was used to couple \nMODFLOW and MT3DMS models, where the coupled model simulated groundwater-flow \nand tritium migration from the HANDLEY test for 50 years, from the date of detonation \nof the HANDLEY test (March 26, 1970) to March 26, 2020. Recharge, hydraulic-conductivity, \nspecific-storage, and effective-porosity distributions were estimated using parameter \nestimation (PEST) by minimizing a weighted composite, sum-of-squares objective function. \nSimulated water-level altitudes in 10 wells, vertical water-level differences between 5 well \npairs, aquifer-test transmissivity estimates in 9 wells, tritium concentrations in 7 wells, \nand drawdowns in wells PM-3-1 and PM-3-2 from groundwater withdrawals in borehole \nER-20-12 were compared to measured equivalents during parameter estimation and \nformally defined the goodness-of-fit or improvement of calibration. This USGS data release \ncontains data, analyses, and model files for the simulations and analyses described in \nthe associated model documentation report (https://doi.org/10.3133/sir20215032). \n\t\t\nSupplementary data and analyses are in the ancillary directory, including transmissivity \nestimates (Appendix A); water-level models to estimate drawdowns (Appendix B); tritium \ndata (Appendix C); the modified hydrostratigraphic framework in the numerical models \n(Appendix D); effective-porosity estimates (Appendix E); the Pahute Mesa–Oasis Valley \ngroundwater model (Appendix F); model-calibration files (Appendix G); and pre-processing \nroutines to build model files (Appendix H). \n\t\t\nThe numerical model was calibrated using a multi-model approach and a two-step process. \nFirst, the groundwater model was calibrated, which consists of (1) a steady-state model \nsimulating steady-state (predevelopment) groundwater flow; and (2) a transient model \nsimulating drawdowns from groundwater withdrawals during the drilling of borehole ER-20-12. \nA transport model was developed that uses the best-fit estimated hydraulic-conductivity \nfield from the calibrated groundwater model and was used to estimate dispersion and effective \nporosities.",
  "distribution": [
    {
      "@type": "dcat:Distribution",
      "accessURL": "https://doi.org/10.5066/P9YRDQSN",
      "description": "Landing page for access to the data",
      "format": "XML",
      "mediaType": "application/http",
      "title": "Digital Data"
    },
    {
      "@type": "dcat:Distribution",
      "description": "The metadata original format",
      "downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.7932df5f-91b8-41cb-9ac4-b02068043452.xml",
      "format": "XML",
      "mediaType": "text/xml",
      "title": "Original Metadata"
    }
  ],
  "identifier": "http://datainventory.doi.gov/id/dataset/USGS_7932df5f-91b8-41cb-9ac4-b02068043452",
  "keyword": [
    "Groundwater",
    "Groundwater Model",
    "MODFLOW-2005",
    "MT3DMS",
    "Nevada",
    "Nevada Test Site",
    "Nye County",
    "PEST",
    "Pahute Mesa",
    "Transport Model",
    "Tritium Migration",
    "USGS:7932df5f-91b8-41cb-9ac4-b02068043452",
    "Underground Nuclear Test",
    "environment",
    "geoscientificInformation",
    "inlandWaters",
    "usgsgroundwatermodel"
  ],
  "modified": "2021-03-15T00:00:00Z",
  "publisher": {
    "@type": "org:Organization",
    "name": "U.S. Geological Survey"
  },
  "spatial": "-116.5716604, 37.23189179, -116.5339270, 37.30583901",
  "theme": [
    "geospatial"
  ],
  "title": "SEAWAT code used to couple MODFLOW and MT3DMS models, and supplemental data used to simulate groundwater flow and tritium transport from the HANDLEY underground nuclear test, Pahute Mesa, southern Nevada"
}