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Using groundwater noble gas measurements to confirm paleorecharge hypotheses at Pahute Mesa, Nevada National Security Site, Nevada, USA

Journal Article · · Hydrogeology Journal
 [1];  [2];  [3];  [1];  [4]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  3. Navarro-Intera, LLC (N-I), Las Vegas, NV (United States)
  4. Desert Research Inst. (DRI), Reno, NV (United States)

Pahute Mesa (Nevada, USA) was the site of 85 underground nuclear tests between 1965 and 1992 whose residual radio-chemical inventory poses a contaminant threat to local groundwater resources. To assess the fate and transport of these radionuclides in groundwater, several geochemical studies, including this one, have been conducted to understand long-term groundwater flow patterns at, and downgradient of, Pahute Mesa. Groundwater samples from the Pahute Mesa area at the Nevada National Security Site were analyzed for noble gases (3He/4He isotopic ratio and He, Ne, Kr, Ar and Xe concentrations) to infer groundwater recharge temperatures and provide additional evidence in support of groundwater flow patterns and the presence of late-pluvial Pleistocene groundwater. These data confirm recent findings (based on groundwater geochemistry and isotope compositions) that most recharge in the area occurred under temperature conditions much cooler than are found today, except near major drainages where ephemeral run of continues to recharge shallow groundwater. These noble gas data indicate that noble gas recharge temperatures and terrigenic He components have been reset where groundwater has flowed upward over barriers formed by caldera margins, or near the regional discharge area (Oasis Valley) where shallow groundwater has interacted with shallow soil gas. This evidence from groundwater noble gas measurements, in combination with other isotopic and geochemical studies, supports the current understanding of the unusual hydrogeology and recharge history of Pahute Mesa.

Research Organization:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
AC52-07NA27344
OSTI ID:
1860877
Report Number(s):
LLNL-JRNL-815880; 1023824
Journal Information:
Hydrogeology Journal, Journal Name: Hydrogeology Journal Journal Issue: 1 Vol. 30; ISSN 1431-2174
Publisher:
SpringerCopyright Statement
Country of Publication:
United States
Language:
English

References (42)

Thermally driven advection for radioxenon transport from an underground nuclear explosion: RADIOXENON PRODUCTION AND TRANSPORT journal May 2016
Steady state fractionation of heavy noble gas isotopes in a deep unsaturated zone journal April 2017
Noble gas signatures in the Island of Maui, Hawaii: Characterizing groundwater sources in fractured systems: NOBLE GAS SIGNATURES IN MAUI, HAWAII journal May 2017
Importance of river water recharge to the San Joaquin Valley groundwater system journal April 2018
A 30,000 yr Continental Paleotemperature Record Derived from Noble Gases Dissolved in Groundwater from the San Juan Basin, New Mexico journal March 1995
On the evaluation of groundwater contamination from underground nuclear tests journal March 2002
Testing the suitability of geologic frameworks for extrapolating hydraulic properties across regional scales journal February 2016
Understanding long-term groundwater flow at Pahute Mesa and vicinity, Nevada National Security Site, USA, from naturally occurring geochemical and isotopic tracers journal September 2021
The relative contributions of summer and cool-season precipitation to groundwater recharge, Spring Mountains, Nevada, USA journal June 1998
Tritiogenic 3He in shallow groundwater journal September 1989
Paleotemperatures and other hydrological parameters deduced from noble gases dissolved in groundwaters; Jordan Rift Valley, Israel journal December 1972
Stable isotopic study of precipitation and spring discharge in southern Nevada journal July 1991
Chemical evolution of shallow groundwater as recorded by springs, Sagehen basin; Nevada County, California journal September 2001
Groundwater residence times in Shenandoah National Park, Blue Ridge Mountains, Virginia, USA: a multi-tracer approach journal September 2001
Determining paleotemperature and other variables by using an error-weighted, nonlinear inversion of noble gas concentrations in water journal August 1999
Denitrification and degassing in groundwater estimated from dissolved dinitrogen and argon journal July 1998
Noble gas signatures in snow journal April 2018
Degassing of 3H/3He, CFCs and SF6 by denitrification: Measurements and two-phase transport simulations journal January 2009
Effects of natural zeolites on field-scale geologic noble gas transport journal September 2020
Beyond Barnwell: Applying lessons learned from the Barnwell site to other historic underground nuclear tests at Pahute Mesa to understand radioactive gas-seepage observations journal October 2020
Geostatistical analysis of tritium, groundwater age and other noble gas derived parameters in California journal March 2016
Noble Gas Excess Air Applied to Distinguish Groundwater Recharge Conditions journal March 2007
Impact of Artificial Recharge on Dissolved Noble Gases in Groundwater in California journal February 2008
Old groundwater influence on stream hydrochemistry and catchment response times in a small Sierra Nevada catchment: Sagehen Creek, California: GROUNDWATER INFLUENCE ON STREAM HYDROCHEMISTRY journal February 2005
An integrated environmental tracer approach to characterizing groundwater circulation in a mountain block: CHARACTERIZING MOUNTAIN BLOCK RECHARGE journal December 2005
Dissolved noble gas and isotopic tracers reveal vulnerability of groundwater in a small, high‐elevation catchment to predicted climate changes journal October 2010
Testing the noble gas paleothermometer with a yearlong study of groundwater noble gases in an instrumented monitoring well: TESTING THE NOBLE GAS PALEOTHERMOMETER journal April 2012
Recharge and source-water insights from the Galapagos Islands using noble gases and stable isotopes: RECHARGE AND SOURCE-WATER INSIGHTS FROM THE GALAPAGOS ISLANDS journal March 2012
Discriminating Underground Nuclear Explosions Leading To Late‐Time Radionuclide Gas Seeps journal June 2020
Chemistry of unsaturated zone gases sampled in open boreholes at the crest of Yucca Mountain, Nevada: Data and basic concepts of chemical and physical processes in the mountain journal June 1998
Carbon and isotopic mass balance models of Oasis Valley-Fortymile Canyon Groundwater Basin, southern Nevada journal April 1987
Palaeotemperature reconstruction from noble gases in ground water taking into account equilibration with entrapped air journal June 2000
Trace gas emissions on geological faults as indicators of underground nuclear testing journal August 1996
Radionuclide Gas Transport through Nuclear Explosion-Generated Fracture Networks journal December 2015
Precipitation in Southern Nevada journal July 1983
Evaluation of Noble Gas Recharge Temperatures in a Shallow Unconfined Aquifer journal September 2009
Paleotemperatures in the Southwestern United States Derived from Noble Gases in Ground Water journal May 1992
Episodic caldera volcanism in the Miocene southwestern Nevada volcanic field: Revised stratigraphic framework, 40Ar/39Ar geochronology, and implications for magmatism and extension journal October 1994
Evaluating the Importance of Barometric Pumping for Subsurface Gas Transport Near an Underground Nuclear Test Site journal January 2019
Summary of hydrogeologic controls on ground-water flow at the Nevada Test Site, Nye County, Nevada report July 1996
Geohydrology of the eastern part of Pahute Mesa, Nevada Test Site, Nye County, Nevada report January 1973
Tracers Reveal Recharge Elevations, Groundwater Flow Paths and Travel Times on Mount Shasta, California journal January 2018