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William Thordarson

Publications and source records attributed to William Thordarson.

At least 19 recordsLinked to original sources
USGS1985

Geohydrology of rocks penetrated by test well USW H-4, Yucca Mountain, Nye County, Nevada

Test well USW H-4 is one of several wells drilled in the southwestern part of the Nevada Test Site for hydraulic testing, hydrologic monitoring, and geophysical logging. The work was performed in cooperation with the U.S. Department of Energy. The rocks penetrated by the well to a total depth of 1,219 m were volcanic tuffs of Tertiary age. Hydraulic coefficients calculated from pumping test data indicate that transmissivity ranged from 200 to 790 sq m/day. A radioactive tracer, borehole flow survey indicated that the two most productive zones during this borehole flow survey occurred in the upper part of the Bullfrog Member of the Crater Flat Tuff, depth interval from 721 to 731.5m, and in the underlying part of the Tram Member, depth interval from 864 to 920m. The water is predominantly a sodium biocarbonate type with small concentrations of calcium, magnesium, and sulfate. The apparent age of this composite water sample was determined by carbon-14 date of 17,200 years before present. (USGS)

Water-Resources Investigations Report↗
USGS1984

Geohydrologic and drill-hole data for test well USW H-3, Yucca Mountain, Nye County, Nevada

Test well USW H-3 is one of a series of test wells drilled in and near the southwestern part of the Nevada Test Site for hydraulic testing, hydrologic monitoring, and geophysical logging. The work was performed in cooperation with the U.S. Department of Energy as part of the Nevada Nuclear Waste Storage investigations. The well penetrated volcanic tuffs of Tertiary age to a depth of 1,219 meters. This report presents data collected to determine the hydraulic characteristics of rocks penetrated. Data on drilling operations, lithology, borehole geophysics, hydrologic monitoring, pumping, swabbing, and injection tests for the well are contained in this report. (USGS)

Open-File Report↗
USGS1984

Geohydrologic and drill-hole data for test well USW H-4, Yucca Mountain, Nye County, Nevada

Data are presented on drilling operations, lithology, geophysical well logs, sidewall-core samples, water-level monitoring, pumping tests, injection tests, radioactive-tracer borehole flow survey, and water chemistry for test well USW H-4. The well is one of a series of test wells drilled in the southwestern part of the Nevada Test Site, Nye County, Nevada, in cooperation with the U.S. Department of Energy. These test wells are part of the Nevada Nuclear Waste Storage Investigations to identify sites for storage of high-level radioactive wastes. Test well USW H-4 was drilled in ash-flow tuff to a total depth of 1,219 meters. Depth to water below land surface was 519 meters or at an altitude of 730 meters above sea level. After test pumping at a rate of 17.4 liters per second for approximately 9 days, the drawdown was 4.85 meters. A radioactive borehole-flow survey indicated that the Bullfrog Member was the most productive geologic unit, producing 36.5 percent of the water in the well. The second most productive geologic unit was the Tram Member, which produced 32 percent of the water. The water in test well USW H-4 is predominantly a soft, sodium bicarbonate type of water typical of water produced in tuffaceous rocks in southern Nevada. (USGS)

Open-File Report↗
USGS1983

Geohydrologic and drill-hole data for test well USW H-1, adjacent to Nevada Test Site, Nye County, Nevada

This report presents data collected to determine the hydraulic characteristics of rocks penetrated in test well USW H-1. The well is one of a series of test wells drilled in and near the southwestern part of the Nevada Test Site, Nye County, Nevada, in a program conducted on behalf of the U.S. Department of Energy. These investigations are part of the Nevada Nuclear Waste Storage Investigations to identify suitable sites for storage of high-level radioactive wastes. Data on drilling operations, lithology, borehole geophysics, hydrologic monitoring, core analysis, ground-water chemistry and pumping and injection tests for well USW H-1 are contained in this report.

Open-File Report↗
USGS1983

Water table in rocks of Cenozoic and Paleozoic age, 1980, Yucca Flat, Nevada Test Site, Nevada

The water table at Yucca Flat, Nevada Test Site, Nevada, occurs in rocks of Paleozoic age and in tuffs and alluvium of Cenozoic age and ranges in altitude from about 2,425 feet to about 3,500 feet. The configuration of the water table is depicted by contours with intervals of 25 to 500 feet. Control for the map consists of water-level information from 61 drill holes, whose locations and age of geologic units penetrated are shown by symbols on the map. (USGS)

Water-Resources Investigations Report↗
USGS1982

Results of hydraulic tests in U.S. Department of Energy's wells DOE-4, 5, 6, 7, 8, and 9, Salt Valley, Grand County, Utah

Six exploratory wells were drilled into the cap rock underlying Salt Valley, Utah, for geologic, geophysical, and hydrologic data to augment information obtained from three previous test wells. Drilling of three other test holes was abandoned due to caving and loss of drilling tools, Before reaching the zone of saturation; the upper 100 meters of cap rock is unsaturated. Within the saturated part of the cap rock, hydraulic heads generally decrease with depth and to the northwest in this part of the valley. Hydraulic conductivity of the cap rock, as determined from pumping tests, ranged from 9.3 X 10 -5 to 2.06 X 10 -1 meters per day; as a result, groundwater flow rates in the cap rock are low. Water ranges from a calcium bicarbonate sulfate type on the western edge of the valley to a calcium magnesium sodium bicarbonate, sulfate, chloride type near the center of the valley. Carbon-14 specific activity for cap-rock water yielded an uncorrected age of about 17,000 to 26,000 years before present near the western edge of the valley and about 41,000 years before present near the center of the valley.

Utah↗
USGS1976

Radiochemical monitoring of water after the Cannikin event, Amchitka Island, Alaska, August 1974 and chemical monitoring from July 1972 to June 1974

Radiochemical data from the Arnchitka Island study area were obtained from water samples collected by the U.S. Geological Survey during August 1974. Tritium determinations were made on 18 samples, and gross alpha and gross beta/ gamma determinations were made on 12 samples. No appreciable differences were found between the data obtained during August 1974 and the data obtained before the Cannikin event. Chemical analyses were made on 4 samples collected in 1971, on 15 samples in 1972, on 11 samples in 1973, and 7 samples in 1974. Comparison of these analyses to analyses of samples collected before the Cannikin event indicates no changes outside of the seasonal range normally found at the sampling locations.

Alaska↗
USGS1976

Radiochemical monitoring of water after the Cannikin event, Amchitka Island, Alaska, May 1974

During May 1974, the U.S. Geological Survey collected water samples from Amchitka Island, Alaska. Tritium determinations were made on 99 water samples, and dissolved gross alpha and gross beta/gamma determinations were made on 34 water samples, No appreciable differences were found between the data obtained in May 1974 and the data obtained before the Cannikin nuclear explosion.

Alaska↗
USGS1971

Wells and springs in California and Nevada within 100 miles of point 37°15' N, 116°25' W, on Nevada test site

Studies of published and unpublished geologic and ground-water data, for an inventory of 6,032 wells and 754 springs in parts of Inyo and Mono Counties, California, and Clark, Esmeralda, Lincoln, and Nye Counties, Nevada, reveal the following information: A complex sequence of granitic, metamorphic, volcanic, and sedimentary rocks of Precambrian to Holocene age are present in the study area. Rocks of lower Precambrian age are metamorphic. These rocks can be divided into five principal types: (a) valley fill, (b) volcanic, (c) carbonate, (d) clastic, and (e) metamorphic and granitic. The valley fill which produces large amounts of water is the best aquifer and it contains the largest number of wells. The carbonate and the volcanic rocks produce small to large amounts of water from fractures or solution cavities. The clastic rocks and the metamorphic and granitic racks produce very little ground water. The greatest concentration of wells in the study area is in the Las Vegas area, which has 79 percent of the total wells inventoried. The Las Vegas area has less than 1 percent of the springs inventoried. The major uses of ground water listed in order of abundance, for the area exclusive of Las Vegas, are irrigation, domestic, public supply, and industrial. The major uses of ground water listed in order of abundance in the Las Vegas area are domestic, irrigation, public supply, and commercial.

California, Nevada↗