Assessment of hydrologic transport of radionuclides from the Gasbuggy underground nuclear test site, New Mexico

Technical Report · Sun Sep 01 04:00:00 EDT 1996

DOI:https://doi.org/10.2172/442146· OSTI ID:442146

Earman, S; Chapman, J; Andricevic, R

The U.S. Department of Energy (DOE) is operating an environmental restoration program to characterize, remediate, and close non-Nevada Test Site locations that were used for nuclear testing. Evaluation of radionuclide transport by groundwater from these sites is an important part of the preliminary risk analysis. These evaluations are undertaken to allow prioritization of the test areas in terms of risk, provide a quantitative basis for discussions with regulators and the public about future work at the sites, and provide a framework for assessing data needs to be filled by site characterization. The Gasbuggy site in northwestern New Mexico was the location of an underground detonation of a 29-kiloton nuclear device in 1967. The test took place in the Lewis Shale, approximately 182 m below the Ojo Alamo Sandstone, which is the aquifer closest to the detonation horizon. The conservative assumption was made that tritium was injected from the blast-created cavity into the Ojo Alamo Sandstone by the force of the explosion, via fractures created by the shot. Model results suggest that if radionuclides produced by the shot entered the Ojo Alamo, they are most likely contained within the area currently administered by DOE. The transport calculations are most sensitive to changes in the mean groundwater velocity, followed by the variance in hydraulic conductivity, the correlation scale of hydraulic conductivity, the transverse hydrodynamic dispersion coefficient, and uncertainty in the source size. This modeling was performed to investigate how the uncertainty in various physical parameters affects calculations of radionuclide transport at the Gasbuggy site, and to serve as a starting point for discussion regarding further investigation at the site; it was not intended to be a definitive simulation of migration pathways or radionuclide concentration values.

• Research Organization: University and Community Coll. System of Nevada, Reno, NV (United States)
• Sponsoring Organization: USDOE Office of Environmental Restoration and Waste Management, Washington, DC (United States)
• DOE Contract Number: AC08-95NV11508
• OSTI ID: 442146
• Report Number(s): DOE/NV/11508--16; ON: DE97003547; IN: DRI 45148
• Country of Publication: United States
• Language: English

Related Subjects

45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE
54 ENVIRONMENTAL SCIENCES
CONTAMINATION
ENVIRONMENTAL TRANSPORT
GASBUGGY EVENT
GROUND WATER
NEVADA TEST SITE
NEW MEXICO
RADIOECOLOGICAL CONCENTRATION
RADIOISOTOPES
REMEDIAL ACTION
RISK ASSESSMENT
UNDERGROUND EXPLOSIONS