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G.L. Locke

Publications and source records attributed to G.L. Locke.

8 recordsLinked to original sources
USGS2001

Selected ground-water data for Yucca Mountain region, southern Nevada and eastern California, through December 1999

The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 34 wells and a fissure (Devils Hole), ground-water discharge at 5 springs and a flowing well, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1999. Data collected prior to 1999 are graphically presented and data collected by other agencies (or as part of other Geological Survey programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992-99. At two water-supply wells median water levels for calendar year 1999 were unchanged from their respective baseline periods. At a nearby observation well, the 1999 median water level was slightly lower (0.1 foot) than its baseline period. At the remaining four wells in Jackass Flats, median water levels for 1999 were slightly higher (0.2 foot to 1.6 feet) than for their respective baseline periods.

Open-File Report↗
USGS1997

Summary of data concerning radiological contamination at well PM-2, Nevada Test Site, Nye County, Nevada

Analysis of water collected during August and September 1993 from well PM-2, on Pahute Mesa at\x11the Nevada Test Site, indicated tritium concentrations of\x1121,000 Bq/L at 610 m below land surface. The Schooner event (U-20u) was detonated in 1968 approximately 270 meterssoutheast of well PM-2 at a working depth of 108.2 meters. The crater created by the Schooner event was about 129.8 meters in radius and\x1163.4 meters in depth. Geologic and hydrologic properties of the stratigraphic units are summarized from historical data. The soil around the well and water in the well were analyzed for radionuclides and water in the well was also analyzed for inorganic constituents and organic (volatile and semivolatile) substances. Close agreement between tritium analyses of water from well PM-2, at different times and at the same depths, confirms the elevated levels of tritium. The highest tritium values in the borehole were at 610 meters below land surface-above the shallowest perforations at 765 meters below land surface. These values were only slightly higher than values found at greater depth in the well.

Open-File Report↗
USGS1993

Ground-water withdrawals, water levels, and ground-water quality in the Houston district, Texas, with emphasis on 1985-89

This report is one in a series of reports prepared by the U.S. Geological Survey, beginning in 1937, on the ground-water resources in the Houston district. The Houston district includes Harris and Galveston Counties, and parts of Brazoria, Fort Bend, Waller, Montgomery, Liberty, and Chambers Counties. The primary emphasis of this report includes ground-water resources information for the district from 1985-89. Some data collected before 1985 and in early 1990 are included to present long-term trends and relations. Ground-water withdrawal in the Houston district decreased from 451 to 419 Mgal/d (million gallons per day) between 1985 and 1989. Public supply used 77 percent of the ground water withdrawn in the district in 1985. From 1985 through 1989, withdrawals for public supply decreased from 349 to 338 Mgal/d, withdrawals for industrial use decreased from 37 to 32 Mgal/d, and withdrawals for irrigation use decreased from 65 to 49 Mgal/d. From 1985 through 1989, ground-water withdrawals decreased from about 197.9 Mgal/d to about 166.9 Mgal/d in the Houston area and increased from about 179.5 Mgal/d to about 180.8 Mgal/d in the Katy area, and remained constant at about 67 Mgal/d in the rest of Harris County. Galveston County ground-water withdrawal decreased from about 6.1 to 4.0 Mgal/d during 1985-89. During 1977-90, water levels in wells completed in the Chicot aquifer in the eastern part of the Houston district rose as much as 160 ft (feet) and declined as much as 80 ft in the western part. During 1985-90, water levels in wells completed in the Chicot aquifer in the western part of the Houston district rose as much as 140 ft, and declined as much as 40 ft in the western part. During 1977-90, water levels in wells completed in the Evangeline aquifer in the southeastern part of the Houston district rose as much as 140 ft and declined as much as 200 ft in the northwestern part. During 1985-90, water levels in wells completed in the Evangeline aquifer in the eastern part of the Houston district rose as much as 40 ft, and declined as much as 140 ft in the northern part. Dissolved-chloride concentrations in water from wells in the Houston district have not changed more than 100 mg/L during 1985-89, except for a decrease at one well in the eastern part of Galveston County. Well KH-65-48-316 yielded water with dissolved-chloride concentration decreasing from 720 mg/L in 1986 to 590 mg/L in 1989.

Texas↗
USGS1990

Ground-water withdrawals, water-level changes, land-surface subsidence, and ground-water quality in Fort Bend County, Texas, 1969-87

Fort Bend County, which has one of the fastest growing populations of all counties in the United States, is dependent entirely on ground water for public supply. Since 1969, at least 90 large-capacity wells have been drilled, of which 57 were public supply wells, 23 were irrigation wells, and 10 were industrial wells. All but seven of the new public-supply wells are located in the northeastern part of the county. The withdrawal of ground water in Fort Bend County increased from 56 million gallons per day in 1969 to 72 million gallons per day in 1982, and then decreased to 53 million gallons per day in 1986. Withdrawals for public supply increased from 4 million gallons per day in 1969 to 28 million gallons per day in 1986. Withdrawals for irrigation averaged 38 million gallons per day during 1969-82 and in 1984, but averaged 20 million gallons per day in 1983, 1985, and 1986. Withdrawals for industrial use declined from 13 million gallons per day in 1969 to 5 million gallons per day in 1986. Water levels in wells screened in the upper unit of the Chicot aquifer generally fluctuated less than 4 feet between 1968-69 and 1987. During the same period, water-level declines in wells screened in the lower unit of the Chicot aquifer ranged from less than 10 feet in most of the western part of the county to 100 feet in the northeastern corner. In the southwestern part of the county, the decline was less than 20 feet. Hydrographs of wells completed in the lower unit of the Chicot showed that water levels continued to decline from 1969 to the early 1980's. The hydrographs of wells located outside of the northeast area generally show a stabilization of water levels corresponding to the reduction in withdrawals after 1982 in Fort Bend County and in the neighboring Houston metropolitan area to the northeast. Withdrawals from the Evangeline aquifer increased from 15 percent of the total in 1969 to 50 percent in 1986. Water-level declines in wells screened in the Evangeline aquifer during the same period ranged from less than 25 feet in the northwestern part of the county to 125 feet in the northeastern part. In the southwestern one-quarter of the county, the decline was less than 50 feet. Declines in the potentiometric surfaces of the aquifers have caused compaction of clay resulting in land-surface subsidence. Between 1906 and 1978, about 65 percent of the county subsided more than 0.5 foot. Studies in the Houston area have shown that most clay compaction occurs in the Chicot aquifer and that the compressibility of the clays increases towards the coast. The total thickness of clays in the Chicot aquifer increases from less than 150 feet in the northwestern part of Fort Bend County to more than 350 feet along the eastern border. The total thickness of clay in the Evangeline aquifer increases from an average of about 700 feet in the northwest to about 1,100 feet in the east. The northeastern part of Fort Bend County is most susceptible to future subsidence because it is the area where the largest water-level declines have occurred and where the thickest, most compressible clays in the county are found. The concentrations of dissolved solids in water from wells in Fort Bend County have not changed appreciably from 1969 to 1987. The median concentrations of dissolved solids are 475 milligrams in water from wells in Fort Bend per liter in water from the upper unit of the Chicot aquifer, 337 milligrams per liter in water from the lower unit of the Chicot aquifer, and 307 milligrams per liter in water from the Evangeline aquifer.

Texas↗