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Gordon L. Nelson

Publications and source records attributed to Gordon L. Nelson.

7 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↗
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↗