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Research about Sweetwater County, Wyoming

Source-linked reports with geographic coverage including Sweetwater County, Wyoming.

At least 19 recordsLinked to original sources
USGS2004

Water resources of Sweetwater County, Wyoming

Sweetwater County is located in the southwestern part of Wyoming and is the largest county in the State. A study to quantify the availability and describe the chemical quality of surface-water and ground-water resources in Sweetwater County was conducted by the U.S. Geological Survey in cooperation with the Wyoming State Engineer’s Office. Most of the county has an arid climate. For this reason a large amount of the flow in perennial streams within the county is derived from outside the county. Likewise, much of the ground-water recharge to aquifers within the county is from flows into the county, and occurs slowly. Surface-water data were not collected as part of the study. Evaluations of streamflow and stream-water quality were limited to analyses of historical data and descriptions of previous investigations. Forty-six new ground-water-quality samples were collected as part of the study and the results from an additional 782 historical ground-water-quality samples were reviewed. Available hydrogeologic characteristics for various aquifers throughout the county also are described. Flow characteristics of streams in Sweetwater County vary substantially depending on regional and local basin characteristics and anthropogenic factors. Because precipitation amounts in the county are small, most streams in the county are ephemeral, flowing only as a result of regional or local rainfall or snowmelt runoff. Flows in perennial streams in the county generally are a result of snowmelt runoff in the mountainous headwater areas to the north, west, and south of the county. Flow characteristics of most perennial streams are altered substantially by diversions and regulation. Water-quality characteristics of selected streams in and near Sweetwater County during water years 1974 through 1983 were variable. Concentrations of dissolved constituents, suspended sediment, and bacteria generally were smallest at sites on the Green River because of resistant geologic units, increased vegetative cover, large diluting streamflows, and large reservoirs. Concentrations of dissolved constituents, suspended sediment, and bacteria generally were largest at sites in the Big Sandy River and Bitter Creek Basins. Some nutrient concentrations and bacteria counts exceeded various State and Federal water-quality criteria. Historical and recent anthropogenic activities contributed to natural sources of many dissolved constituents and suspended sediment. Both water-table and artesian conditions occur in aquifers within the county. Shallow ground water is available throughout the county, although much of it is only marginally suitable or is unsuitable for domestic and irrigation uses mainly because of high total dissolved solids (TDS) concentrations. Suitable ground water for livestock use can be found in most areas of the county. Ground-water quality tends to deteriorate with increasing distance from recharge areas and with increasing depth below land surface. Ground water from depths of greater than a few thousand feet tends to have TDS concentrations that make it moderately saline to briny. In some areas even shallow ground water has moderately saline TDS concentrations. Specific constituents in parts of some aquifers in the county occur in relatively high concentrations when compared to U.S. Environmental Protection Agency drinking-water standards. Relatively high concentrations of sulfate, fluoride, boron, iron, and manganese were found in several aquifers. Many ground-water samples from the Battle Spring aquifer in the Great Divide Structural Basin had high radionuclide concentrations. The estimated mean daily water use in Sweetwater County in 2000 was 170.73 million gallons per day. Irrigation was the largest single use of water in the county with an estimated mean use of more than 92 million gallons per day. Surface water irrigation accounted for nearly 90 percent of the total irrigation water used in 2000. Although ground water is used to a much lesser extent than surface water, in many areas of the county it is the only source of water available.

Wyoming↗
USGS1979

Soil-gas helium concentrations in the vicinity of a uranium deposit, Red Desert, Wyoming

A survey of the helium concentration in soil-gas was conducted in the Red Desert Area, Sweetwater County, Wyoming. The area studied is directly over a low-grade uranium deposit that may be suitable for recovery by in-situ leaching techniques. The area was sampled twice, once in December, 1977, and again in July, 1978. Wind was a significant factor affecting the helium concentrations. Wind gusts exceeded 110 km/hr (70 mph) during the December, 1977, sampling; wind gusts did not exceed 30 km/hr (20 mph) during the July, 1978, sampling. The average helium concentration for all the July, 1978, soil-gas samples was about twice the average of the December, 1977, samples. In addition, a contour plot of the July, 1978, soil-gas samples showed an area of higher helium values that corresponds to the location of anomalies detected by other exploration techniques, and may be associated with the uranium deposit.

Wyoming↗
USGS1956

Uranium-bearing coal in the central part of the Great Divide basin, Sweetwater County, Wyoming

Field work leading to this report was done by the U.S. Geological Survey for the Division of Raw Materials of the U.S. Atomic Energy Commission. Nearly 24 townships were mapped in the central part of the Great Divide Basin, Sweetwater County, Wyoming. Fourteen of these townships contain outcrops of uranium-bearing coal. Thirty coal beds were mapped, but only seven of them have uranium-bearing coal reserves as defined in this report. Coal beds 2.5 or more feet thick are considered in calculating coal reserves, and of these, only beds containing 0.003 or more percent uranium are considered in calculating reserves of uranium in coal. Reserves of uranium in coal ash include those beds 2.5 or more feet thick that contain 0.015 or more percent uranium in coal ash. Measured and indicated coal reserves total about 700,000,000 short tons which contain about 2,600 short tons of uranium in the coal, or about 2,400 short tons of uranium in the coal ash. Strippable reserves, defined as reserves in beds beneath 60 or less feet of overburden, are about 250,000,000 short tons of coal containing about 1,100 short tons of uranium in coal, or about 600 tons of uranium in coal ash. The thickest coal beds underlie a relatively narrow belt that trends northwest and coincides approximately with the axis of the Red Desert syncline. The coal beds contain the most uranium on the east flank of the syncline near the southwesternmost edge of the Battle Spring formation (new). This formation is of early and middle Eocene age and consists predominantly of very coarse-grained arkosic sandstone which is highly permeable. It intertongues southwestward with the Tess permeable Green River and Wasatch formations. The Green River formation consists from youngest to oldest of the Morrow Creek and Laney shale members and the Tipton and Luman (new) tongues. The Wasatch formation interfingers with the Green River formation and consists from youngest to oldest of the Cathedral Bluffs, Niland, and Red Desert tongues. The latter two are here recognized for the first time and contain all the coal beds in the Wasatch formation. The Morrow Creek member of the Green River formation is of middle Eocene age. The Laney member and Cathedral Bluffs tongue of the Green River and Wasatch formation, respectively intertongue and are in part equivalent, and are of early or middle Eocene age. The other units are of early Eocene age. A broad gentle arch which is either the eastern extension of the Wamsutter arch, or a separate arch en echelon to it, separates the Washakie Basin the southeastern part of the map area from the Red Desert syncline in the northeastern part. The Red Desert syncline plunges gently northwest into the nearly circular structural Niland basin. The south flank of the Wamsutter(?) arch dips southeastward at an average rate of about 230 feet per mile. The northern flank of the arch dips northeastward at an average rate of about 140 feet per mile. North of the Niland basin, the structure is more complex and is dominated by a northwestwardtrending graben which parallels and includes the Cyclone Rim in the northern part of die map area. Schroeckingerite deposits in the northeastern part of the map area lie within this graben in a sequence of arkosic sandstone and clay shale stratigraphically equivalent to the lower part of the Cathedral Bluffs tongue of the Wasatch formation and to the uppermost part of the Tipton tongue of the Green River formation. Weakly radioactive tuffaceous sandstone beds of the Browns Park formation that probably once blanketed the entire Great Divide Basin are preserved a short distance north and northwest of the schroeckingerite deposits. The geologic settings of the schroeckingerite and uranium-bearing coal are similar and their source of uranium is probably the same. The uranium probably was leached from tuffaceous beds in the Browns Park formation and carried to its present site of deposition by groundwater whose circulation was guided by structure and changes in facies.

Wyoming↗
USGS1954

Airborne radioactivity survey of parts of Sand Creek SW and Sand Creek SE quadrangles, Sweetwater county, Wyoming

The accompanying map shows the results of an airborne radioactivity survey in 125 square miles of Sand Creek SW and Sand Creek SE quadrangles, Wyoming. This area is part of a larger survey made in southern Carbon and Sweetwater counties by the U.S. Geological Survey, November 9-24, 1953. The work was undertaken as part of a cooperative program with the U.S. Atomic Energy Commission. The survey was made with scintillation detection equipment mounted in a C-47 aircraft and consisted of parallel east-west flight lines spaced at quarter mile intervals, flown approximately 500 feet above the ground. Aerial photographs were used for pilot guidance, and the flight path of the aircraft was recorded by a gyrostabilized, continuous-strip-film camera. The distance of the aircraft from the ground was measured with a continuously recording radio altimeter. The width of the zone on the ground form which the anomalous radiation is measured at the nominal 500 foot flight altitude varied with the areal extent and the intensity of radioactivity of the source. For strong sources of radioactivity the width of the zone may be as much as 1,400 feet. Thus, quarter mile spacing of the flight lines would be adequate to detect anomalies from strong sources of radioactivity; however, small areas of considerable radioactivity midway between flight lines may not be noted. The approximate locations of nine radioactivity anomalies are shown on the accompanying map. The plotted position of the anomalies may be in error by as much as a quarter mile owing to the errors in available base maps or to the existence of areas on the base maps up to several square miles in which it is impossible to find and plot recognizable landmarks. The present technique of airborne radioactivity measurement does not permit distinguishing between activity due to thorium and that due to uranium. An anomaly, therefore, may represent radioactivity due entirely to one or to a combination of these elements. The radioactivity anomalies shown on the accompanying map cannot be interpreted in terms of either radioactive content or the extent of the source materials. Any particular anomaly may represent slightly greater-than-average radioactivity over an area of a few thousand square feet or high radioactivity over an area of a few hundred square feet. Thus radioactivity anomalies indicate localities of more-than-average radioactivity and, therefore, suggest areas in which uranium or thorium deposits are more likely to occur.

Wyoming↗