27-3 Integrated Hydro-geophysical Characterization of an Anthropogenic Perched Aquifer at the Waste Isolation Pilot Plant
Session: From Data to Decision: Integrating Geophysics, Data Systems, and Modeling for Aquifer Characterization in Data-Sparse Regions (Posters)
Poster Booth No.: 39
Presenting Author:
Pushpa DahalAuthors:
Dahal, Pushpa R.1, Rucker, Dale F.2, Ward, Anderson3, Lepchitz, Zachary4, Carroll, Kenneth C.5(1) Department of Plant and Environment Sciences, New Mexico State University, Las Cruces, NM, USA, (2) hydroGEOPHYSICS, Inc., Tucson, Arizona, USA, (3) U.S. Department of Energy (DOE), Waste Isolation Pilot Plant (WIPP), Carlsbad, New Mexico, USA, (4) U.S. Department of Energy (DOE), Waste Isolation Pilot Plant (WIPP), Carlsbad, New Mexico, USA, (5) Department of Plant and Environmental Sciences, New Mexico State University, Las Cruces, NM, USA,
Abstract:
An anthropogenic perched aquifer has formed due to the interaction of natural stratigraphy and discharges from unlined impoundments at the Waste Isolation Pilot Plant (WIPP) site in New Mexico. Characterizing its spatial extent and potential connectivity to the regional groundwater system requires a higher data density than is currently available using existing wells. This study develops an integrated hydro geophysical approach, combining electrical resistivity tomography, induced polarization, borehole resistivity, lithology, and water-quality data to characterize the perched aquifer. Archie’s law parameters were estimated from perched formation petrophysical properties. This approach characterizes the aquifer geometry, lateral extent, and hydrodynamic behavior, constraining the perched horizon that is localized between the lower-permeability Dewey Lake Redbeds and the overlying Santa Rosa Sandstones. Resistivity and chargeability data confirmed that the low-resistivity features are due to perched groundwater saturation and salinity (i.e., not elevated clay content), and a change in cementation forms the impervious horizon of the aquifer. Resistivity contours, which infer water-saturated conditions, closely matched piezometric equipotential elevations, exhibiting a strong correlation (R² = 0.89), and confirmed the geophysical characterization of the perched water table. This data fusion framework provides a systematic approach to delineate the geometry and extent of anthropogenic perched aquifers.
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Integrated Hydro-geophysical Characterization of an Anthropogenic Perched Aquifer at the Waste Isolation Pilot Plant
Category
Discipline > Geophysics/Geodynamics
Description
Session Format: Poster
Presentation Date: 5/19/2026
Presentation Room: Alvarado D/E
Poster Booth No.: 39
Author Availability: 2:00-4:00 p.m.
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