Geohydrologic data collected from shallow neutron-access boreholes and resultant-preliminary geohydrologic evaluations, Yucca Mountain area, Nye County, Nevada
- Raytheon Services Nevada, Las Vegas, NV (United States)
In cooperation with the US Department of Energy, 74 neutron-access boreholes were drilled in and near the southwestern part of the Nevada Test Site, Nye County, Nevada. Drilling, coring, sample collection and handling, and lithologic and preliminary geohydrologic data are presented in this report. The boreholes were drilled in a combination of alluvium/colluvium, ash-flow tuff, ash-fall tuff, or bedded tuff to depths of 4.6 to 36.6 meters. Air was used as a drilling medium to minimize disturbance of the water content and water potential of drill cuttings, core, and formation rock. Drill cuttings were collected at approximately 0.6-meter intervals. Core was taken at selected intervals from the alluvium/colluvium using drive-coring methods and from tuff using rotary-coring methods. Nonwelded and bedded tuffs were continuously cored using rotary-coring methods. Gravimetric water-content and water-potential values of core generally were greater than those of corresponding drill cuttings. Gravimetric water-content, porosity, and water-potential values of samples generally decreased, and bulk density values increased, as the degree of welding increased. Grain-density values remained fairly constant with changes in the degree of welding. A high degree of spatial variability in water-content and water-potential profiles was noted in closely spaced boreholes that penetrate similar lithologic subunits and was also noted in adjacent boreholes located in different topographic positions. Variability within a thick lithologic unit usually was small. 18 refs., 21 figs., 17 tabs.
- Research Organization:
- Geological Survey, Denver, CO (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AI08-92NV10874
- OSTI ID:
- 60914
- Report Number(s):
- USGS-OFR--92-657; ON: DE95005995
- Country of Publication:
- United States
- Language:
- English
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Drilling and coring methods that minimize the disturbance of cuttings, core, and rock formation in the unsaturated zone, Yucca Mountain, Nevada
COMPLETION REPORT FOR WELL CLUSTER ER-5-3
Related Subjects
54 ENVIRONMENTAL SCIENCES
COMPILED DATA
DATA ACQUISITION
DRILL CORES
EXPERIMENTAL DATA
HIGH-LEVEL RADIOACTIVE WASTES
HYDROLOGY
LITHOLOGY
NEUTRON LOGGING
RADIOACTIVE WASTE DISPOSAL
RADIOACTIVE WASTE FACILITIES
RADIOECOLOGICAL CONCENTRATION
SITE CHARACTERIZATION
TRITIUM
UNDERGROUND DISPOSAL
WATER SATURATION
WELL DRILLING
YUCCA MOUNTAIN
Yucca Mountain Project