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Gordon L. Nelson

Publications and source records attributed to Gordon L. Nelson.

9 recordsLinked to original sources
USGS1999

Water-quality assessment of the Cook Inlet Basin, Alaska — Environmental setting

The Cook Inlet Basin in Alaska is one of 59 study units selected for study for water-quality assessment as part of the U.S. Geological Survey's National Water-Quality Assessment program. The Cook Inlet Basin study unit encompasses the fresh surface and ground waters in the 39,325 square-mile area that drains to Cook Inlet, but does not include the marine waters of Cook Inlet. This report describes the natural factors (climate, physiography, geology, soils, land cover) and the human factors (population, land use, water use) that affect water quality, which is the first step in designing and conducting a multidisciplinary regional water-quality assessment. The surface- and ground-water hydrology, and the aquatic ecosystems of the Cook Inlet Basin are described. The report provides an overview of existing water-quality conditions and summarizes the results of selected water-quality studies of the basin.

Alaska↗
USGS1984

VERTICAL MOVEMENT OF GROUND WATER UNDER A LANDFILL, ANCHORAGE, ALASKA.

A thorough review of existing ground-water information may, in some cases, be adequate to estimate rates of migration of pollutants. Analysis of data from well-performance tests and from hydrologic-data stations near a landfill in Anchorage, Alaska, indicates that pollutants migrating downward toward a confined aquifer that supplies water to three municipal wells near the landfill do not pose an imminent threat to the water supply. The analysis helps alleviate some concerns that pollution of municipal wells is imminent. However, because the errors in estimating hydraulic conductivities may be as great as a factor of three, the analysis should not be used as justification to discontinue monitoring migration of the leachate.

Conference Paper↗
USGS1982

Vertical movement of ground water under the Merrill Field landfill, Anchorage, Alaska

Shallow groundwater under the Merrill Field sanitary landfill at Anchorage is polluted by leachate. Wells, including three Municipal-supply wells, obtain water from two confined aquifers 100-300 feet beneath the landfill area. Aquifer-test data and information on subsurface geology, ground-water levels, and properties of materials were used to estimate vertical gradients and vertical permeabilities under the landfill. The authors ' best estimates ' of vertical permeabilities of two confining units are 1 x 10 super -2 foot per day and 2 x 10 super -4 foot per day. Theoretical travel-time calculations indicate that minor amounts of pollutants may reach the upper confined aquifer after many tens of years, but that water of the composition of the leachate probably would not reach the aquifer for more than three centuries. The range of error in the theoretical travel-time calculations is likely to be plus or minus a factor of two or three. (USGS)

Open-File Report↗
USGS1981

Hydrology and the effects of industrial pumping in the Nikiski area, Alaska

Ground-water consumption for industrial use at Nikiski increased from about 1 million gallons per day in 1968 to 4.2 million gallons per day in 1979. Water managers and local citizens are concerned that industrial pumping may reduce the esthetic and recreational value of local lakes. Some lake levels have declined as much as 8 feet since pumping began; the greatest declines occurred in lakes nearest the center of pumping. Ground water occurs in three aquifers. The upper aquifer is unconfined and is hydraulically connected to most lakes and streams in the area. The upper two aquifers are hydraulically connected through a leaky confining layer, and water levels in the two aquifers fluctuate synchronously with changes in precipitation and changes in pumping from either aquifer. The hydraulic connection of the lower confined aquifer, the deepest of the three aquifers, to the other two aquifers is poor. Drawdowns caused by pumping have stabilized in all three aquifers. This indicates that the pumping is in equilibrium with the hydrologic boundaries. In the lower two aquifers, the potentiometric surfaces near some production wells are below sea level; however, no salt water has intruded the aquifers as far as the pumped wells. If intrusion occurs or if additional water supplies are needed, another potential site for ground-water development is the middle Beaver Creek basin, 7-10 miles east of the industrial area.

Alaska↗
USGS1981

Hydrologic reconnaissance near Fourth of July Creek, Seward, Alaska

The 1.3-square-mile alluvial fan of Fourth of July Creek, Seward , Alaska, is being developed as an industrial area and port. Fourth of July Creek is a glacier-fed stream that occupies a braided channel near the middle of the fan. The presence of glacial flow during the summer and low discharge during the winter make streamflow a poor source of water for municipal and industrial use. Water infiltrates the fan from streams and precipitation and recharges an unconfined alluvial aquifer. Average recharge is 40-50 cubic feet per second, and ground water flows toward the coast where it discharges in springs and a 0.3-mile gaining reach of the creek. Properties and concentrations of all measured chemical constituents of water samples from two wells were less than the maximum amounts recommended for drinking water. Both the aquifer and the overlying unsaturated materials are coarse grained. The coarse-grained materials are poor filters and make the aquifer susceptible to pollution by contaminants disposed of or spilled on the alluvial fan. Avalanches may block the creek and cause flooding by directing streamflow into new or abandoned channels. (USGS)

Water-Resources Investigations Report↗
USGS1980

Hydrogeology of the Seldovia area, Alaska

Surficial materials in the Seldovia area, Alaska, are mapped as glacial drift over sedimentary bedrock, glacial drift over igneous and metamorphic bedrock, valley-bottom, alluvium, alluvial fan deposits, beach and intertidal deposits, and peat. Unconsolidated materials are generally less than 10 feet thick except in well-drained glacial deposits along the Seldovia-Jakolof Bay Road and in depressions in the bedrock surface. These depressions are poorly drained and commonly contain peat bogs. Development of domestic wells (1-15 gallons per minute) may be possible from unconsolidated materials and sedimentary bedrock, but larger water requirements must be met from surface-water sources. In areas having the water table or top of bedrock at shallow depths, effluent from sewage disposal systems may cause pollution of the land surface and nearby surface water. Seepage from hillside aquifers and unstable land along the coast of Kachemak Bay may adversely affect roads and structures. (USGS)

Open-File Report↗
USGS1978

Hydrologic information for land-use planning, Fairbanks vicinity, Alaska

The flood plain on the Chena and Tanana Rivers near Fairbanks, Alaska, has abundant water in rivers and in an unconfined alluvial aquifer. The principal source of ground water is the Tanana River, from which ground water flows northwesterly to the Chena River. Transmissivity of the aquifer commonly exceed 100 ,000 sq ft. The shallow water table (less than 15 ft below land surface), high hydraulic conductivity of the sediments and cold soil give the flood plain a high susceptibility to pollution by onsite sewerage systems. The Environmental Protection Agency recommended maximum concentrations for drinking water may be exceeded in surface water for manganese and bacteria and in ground water for iron, manganese, and bacteria. Residents of the uplands obtain water principally from a widely-distributed fractured schist aquifer. The aquifer is recharged by local infiltration of precipitation and is drained by springs on the lower slopes and by ground-water flow to alluvial aquifers of the valleys. The annual base flow from basins in the uplands ranged from 3,000 to 100,000 gallons per acre; the smallest base flows occur in basins nearest the city of Fairbanks. The thick silt cover and great depth to the water table give much of the uplands a low susceptibility to pollution by onsite sewage disposal. Ground water is locally high in nitrate, arsenic, iron , and manganese. (Woodard-USGS)

Alaska↗