HR: 14:15h
AN: IA33A-02    [Abstracts]
TI: Conceptual-Model-Driven Characterization of the Culebra Dolomite at the Waste Isolation Pilot Plant
AU: * Beauheim, R L
EM: rlbeauh@sandia.gov
AF: Sandia National Laboratories, Repository Performance Department, 4100 National Parks Highway, Carlsbad, NM 88220, United States
AU: McKenna, S A
EM: samcken@sandia.gov
AF: Sandia National Laboratories, National Security Applications Department, P.O. Box 5800, MS0751, Albuquerque, NM 87185-0751, United States
AU: Hart, D B
EM: dbhart@sandia.gov
AF: Sandia National Laboratories, National Security Applications Department, P.O. Box 5800, MS0751, Albuquerque, NM 87185-0751, United States
AB: The Culebra Dolomite Member of the Rustler Formation would be the primary groundwater transport pathway for radionuclides released from the Waste Isolation Pilot Plant (WIPP) by inadvertent human intrusion. The WIPP, located in southeastern New Mexico, is the U.S. Department of Energy's underground repository for transuranic and mixed wastes. Characterization of the Culebra began in the late 1970s and showed that the Culebra is highly heterogeneous with transmissivity varying over ten orders of magnitude. Although multiple generations of groundwater flow models had been developed for the Culebra by the time the WIPP was first licensed in 1999, the Environmental Protection Agency (a WIPP regulator) felt that a coherent conceptual model relating transmissivity variations to their cause(s) was lacking. A conceptual model relating Culebra transmissivity to geologic factors was developed and combined with a monitoring well network optimization study to identify locations where new wells would be of high value. Since 2003, 16 new wells have been sited, drilled, and tested. The wells provided confirmation of expected geologic conditions, local head and transmissivity measurements, and transient response data during large-scale pumping tests. The information provided by these new wells has been used in the development of a new groundwater flow model for the WIPP that provides the best representation yet achieved of measured heads and transient responses observed during large-scale pumping tests at the site. This model will be used in future performance assessment calculations for the WIPP.
DE: 1829 Groundwater hydrology
DE: 1846 Model calibration (3333)
DE: 1847 Modeling
DE: 1848 Monitoring networks
DE: 1894 Instruments and techniques: modeling
SC: International Association of Hydrogeologists, Canadian National Chapter [IA]
MN: 2009 Joint Assembly