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R. L. Glass

Publications and source records attributed to R. L. Glass.

16 recordsLinked to original sources

Ground-water conditions and quality in the western part of Kenai Peninsula, southcentral Alaska

The western part of Kenai Peninsula in southcentral Alaska is bounded by Cook Inlet and the Kenai Mountains. Ground water is the predominant source of water for commercial, industrial, and domestic uses on the peninsula. Mean daily water use in an oil, gas, and chemical processing area north of Kenai is more than 3.5 million gallons. Unconsolidated sediments of glacial and fluvial origin are the most productive aquifers. In the upper (northwestern) peninsula, almost all water used is withdrawn from unconsolidated sediments, which may be as thick as 750 feet. In the lower peninsula, unconsolidated sediments are thinner and are absent on many hills. Water supplies in the lower peninsula are obtained from unconsolidated sediments and bedrock, and a public-water supply in parts of Homer is obtained from Bridge Creek. Throughout the peninsula, ground-water flow occurs primarily as localized flow controlled by permeability of aquifer materials and surface topography. The concentration of constituents analyzed in water from 312 wells indicated that the chemical quality of ground water for human consumption varies from marginal to excellent. Even though the median concentration of dissolved solids is low (152 milligrams per liter), much of the ground water on the peninsula does not meet water-quality regulations for public drinking water established by the U.S. Environmental Protection Agency (USEPA). About 8 percent of wells sampled yielded water having concentrations of dissolved arsenic that exceeded the USEPA primary maximum contaminant level of 50 micrograms per liter. Concentrations of dissolved arsenic were as great as 94 micrograms per liter. Forty-six percent of wells sampled yielded water having concentrations of dissolved iron greater than the USEPA secondary maximum contaminant level of 300 micrograms per liter. Unconsolidated sediments generally yield water having calcium, magnesium, and bicarbonate as its predominant ions. In some areas, ground water at depths greater than a few hundred feet may be naturally too salty for human consumption. The leaking and spilling of fuel and chemical products and the disposal of industrial wastes has degraded the quality of ground water at numerous sites.

Open-File Report↗

Hydrologic and water-quality data for U.S. Coast Guard Support Center Kodiak, Alaska, 1987-89

Hydrologic and water-quality data were collected at the U.S. Coast Guard Support Center Kodiak on Kodiak Island, Alaska, to determine regional ground-water conditions and if contamination of soils, ground water, or surface water has occurred. Eighteen areas of possible contamination were identified. Ground-water levels, surface- water stages, surface-water discharges, and results of field and laboratory analyses of soil and water samples are presented in tabular form. Many quality-assurance samples had detectable concentrations of methylene chloride and 1,2-dichloroethane, which may be due to sampling or laboratory contamination. Concentrations were as great as 5.9 micrograms per liter for methylene chloride and 2.6 micrograms per liter for 1,2-dichloroethane. Excluding 1,2-dichloroethane, most soil, ground-water, and surface-water samples contained no detectable concentrations of the organic constituents that were analyzed. Chemical analyses were performed on two lake-bed-material samples and more than 100 soil samples. The median lead concentration was 9.8 milligrams per kilogram. Concentrations of tetrachloroethene were as great as 1.1 milligram per kilogram in soils near a laundry. Water samples were collected from 101 wells. The maximum benzene concentration detected in ground water was 78 micrograms per liter from a well at the air station near a site where aviation fuel was spilled. Wells near a laundry yielded water having concentrations of tetrachloroethene as great as 3,000 micrograms per liter, and vinyl chloride as great as 440 micrograms per liter. A well in a former aviation gasoline storage area yielded water with a concentration of trichloroethene as great as 66 micrograms per liter. Water samples were collected from 59 sites on streams, lakes, or ponds. Surface-water samples had much lower concen- trations of organic compounds; the highest concentration of benzene was 2.2 micrograms per liter in a stream near a former aviation-fuel storage area and the maximum vinyl chloride concentration was 15 micrograms per liter in a stream near a former landfill. Tetrachloroethene and trichloroethene were not detected in any surface-water samples.

Open-File Report↗

Ground-water levels in an alluvial plain between the Tanana and Chena Rivers near Fairbanks, Alaska 1986-93

The aquifer of an alluvial plain between the Tanana and Chena Rivers near Fairbanks, Alaska, generally consists of highly transmissive sands and gravels under water-table conditions. During 1986-88, the U.S. Geological Survey studied the distribution of ground-water levels in the alluvial plain between Moose Creek Dam and the confluence of the Tanana and Chena Rivers. Moose Creek Dam is a flood-control structure on the Chena River that impounds water only during high flows in the Chena River or during tests of the dam's control gates. Ground-water-level information is needed to help design and place septic systems, buildings, and drainage structures. Using 38 existing wells and 83 wells drilled for this study during 1986 and 1987, ground-water levels were measured to determine the depth to the water table, its seasonal variation, and its relation to changes in river and reservoir stages. Water levels were continuously measured in 10 wells and periodically measured in 110 other wells until August 1988. During 1989, water levels were measured at least once in 59 wells. Three wells were equipped with water-level recorders through 1993. River stages were measured continuously at one gaging station on the Tanana River and at two stations on the Chena River. During summer months of 1986-88, stages and discharges in the Chena River were generally less than long-term mean monthly values, whereas mean monthly stages and discharges in the Tanana River fluctuated above and below long-term mean monthly values. Depths to water in monitoring wells ranged from slightly above land surface to about 21 feet below land surface. Depths to water in the alluvial plain were within 10 feet of land surface in most areas, but were within 5 feet of land surface in many low-lying areas. In general, the water table sloped to the northwest, from the Tanana River to the Chena River, at a gradient of about 4 feet per mile. Water levels in wells within about half a mile of either river responded rapidly to changes in river stage. During summer months of 1989-93, stages and discharges in the Chena River were generally higher than those during 1986-88, whereas stages and discharges in the Tanana River were similar to those during 1986-88. During 1989, peak water levels were higher in more than half the wells measured than during peak levels observed during 1986-88. Peak water levels were also 1.9 to 3.3 feet higher in 1991 or 1992 than peak values during 1986-88 in three wells equipped with water-level recorders. Water levels in wells near Moose Creek Dam responded rapidly to changes in water levels behind the dam. During one impoundment, water levels in a well 0.1 mile from the dam rose approximately 7 feet, to 4.8 feet below land surface.

Alaska↗

Glaciers along proposed routes extending the Copper River Highway, Alaska

Three inland highway routes are being considered by the Alaska Department of Transportation and Public Facilities to connect the community of Cordova in southcentral Alaska to a statewide road system. The routes use part of a Copper River and Northwest Railway alignment along the Copper River through mountainous terrain having numerous glaciers. An advance of any of several glaciers could block and destroy the roadway, whereas retreating glaciers expose large quantities of unconsolidated, unvegetated, and commonly ice-rich sediments. The purpose of this study was to map historical locations of glacier termini near these routes and to describe hazards associated with glaciers and seasonal snow. Historical and recent locations of glacier termini along the proposed Copper River Highway routes were determined by reviewing reports and maps and by interpreting aerial photographs. The termini of Childs, Grinnell, Tasnuna, and Woodworth Glaciers were 1 mile or less from a proposed route in the most recently available aerial photography (1978-91); the termini of Allen, Heney, and Schwan Glaciers were 1.5 miles or less from a proposed route. In general, since 1911, most glaciers have slowly retreated, but many glaciers have had occasional advances. Deserted Glacier and one of its tributary glaciers have surge-type medial moraines, indicating potential rapid advances. The terminus of Deserted Glacier was about 2.1 miles from a proposed route in 1978, but showed no evidence of surging. Snow and rock avalanches and snowdrifts are common along the proposed routes and will periodically obstruct the roadway. Floods from ice-dammed lakes also pose a threat. For example, Van Cleve Lake, adjacent to Miles Glacier, is as large as 4.4 square miles and empties about every 6 years. Floods from drainages of Van Cleve Lake have caused the Copper River to rise on the order of 20 feet at Million Dollar Bridge.

Water-Resources Investigations Report↗

Hydrologic and mass-movement hazards near McCarthy, Wrangell-St. Elias National Park and Preserve, Alaska

At the confluence of McCarthy Creek and the Kennicott River, about 1 mile from the terminus of Kennicott Glacier, Alaska, McCarthy Creek and Kennicott River basins are prone to several natural hazards including floods; formation and failure of natural dams; stream erosion and sediment deposi- tion; snow avalanches; aufeis; and the mass wasting of rock, soil, and debris. Low-lying areas along the Kennicott River flood annually, commonly during late July or early August, as a result of outbursts from glacier-dammed lakes, but these floods can occur during any month of the year. Flood plains along McCarthy Creek and its tributaries are frequently flooded and prone to rapid erosion and deposition during intense rainfall and periods of rapid snow- melt. Sediments from continual mass wasting accumu- late in stream channels and are mobilized during floods. Several lateral erosion, scour, and deposition resulting from floods in September 1980 and August 1985 destroyed bridges and several historic structures at McCarthy were jeopardized by the rapidly eroding northern streambank of McCarthy Creek. Flood discharges were determined indirectly using the slope-area method at two high-gradient reaches on the Kennicott River, four on McCarthy Creek, and one on Nikolai Creek. During the flood of September 13, 1980, peak discharge for McCarthy Creek at McCarthy was 4,500 cubic feet per second.

Alaska↗

Simulation of ground-water flow at Anchorage, Alaska, 1955-83

The groundwater system at Anchorage, Alaska was analyzed by using a two-layer three-dimensional mathematical model. By use of existing data, both nonpumping and pumping steady-state conditions and transient conditions were simulated. Under steady-state conditions, calculated directions of groundwater flow were similar to observed flow patterns, and calculated stream discharges generally were within 10% of observed values. However, in many parts of the modeled area computed hydraulic head values were more than 20 ft higher or lower than observed values. Hydraulic conductivity and transmissivity are the most sensitive hydraulic parameters under steady-state conditions. Under steady-state conditions, a pumping rate of 18.8 Mgal/d lowers heads in the confined aquifer by as much as 30 ft, but reduces streamflow by less than 5%. Transient conditions show that drawndowns due to withdrawals by production wells follow similar patterns of nearby observation wells. On the basis of analytical techniques, the confining layer does not appear to hold significant quantities of water. (USGS)

Water-Resources Investigations Report↗

Summary of water resources data for the Girdwood-Alyeska Area, Alaska

Surface water, groundwater and water quality data for the Girdwood-Alyeska area are presented in graphs, tables, and maps. Surface water data include streamflow measurements and water quality analyses from three streams. Groundwater data include descriptions of 106 wells, with lithologic and water quality data from selected wells. The report also contains a map depicting the geology of the area. (USGS)

Open-File Report↗

Map showing depth to bedrock, Anchorage, Alaska

Knowledge of the physical and hydrologic characteristics of geologic materials is useful in determining the availability of groundwater for public and domestic supply and the suitability of areas for on-site septic systems. A generalized map of the Anchorage area shows the approximate distance from land surface to the top of the bedrock surface. Four depth zones are shown. The depths were determined from lithologic data contained in drillers ' logs. (USGS)

Open-File Report↗

Ground-water levels in Anchorage, Alaska, 1985

Water-level data collected during 1985 for 146 Anchorage wells deeper than 40 feet are presented. Hydrographs of water levels in 20 wells for the period 1970 through 1985 are also given. The report describes groundwater conditions and seasonal fluctuations in water levels, and includes pumpage figures and well-construction data.

Alaska↗

Water resources near Dillingham in the Bristol Bay Area, Alaska

Dillingham, the largest community in the Bristol Bay area of Alaska, lies near the confluence of the Wood and Nushagak Rivers. Mean annual discharges for the Wood and Nushagak Rivers are 4,824 and 22,650 cu ft/sec. Flows generally are greatest in May through July and lowest in January through April. The surface waters are a calcium bicarbonate type and have low concentrations of dissolved solids and suspended sediments. Water in the Wood-Nushagak estuary near Dillingham during a high tide in autumn 1985 had specific conductance values ranging from 110 to 3,000 microsiemens/cm. Groundwater is the predominant source of public, private, and commercial/industrial supply. Wells range in depth from 20 to 213 ft, yield up to 225 gal/min, and have water levels that range from 4 to 76 ft below land surface. All water levels measured during June and July 1986 were above sea level. Samples of groundwater contained < 500 mg/L dissolved solids but concentrations of iron and manganese were as great as 870 and 1,200 mg/L, respectively. Peak water use is in midsummer. In 1986, peak use in the townsite area was between 300,000 and 400,000 gal/day whereas in previous years it has been as great as 1 million gal/day. (Author 's abstract)

Water-Resources Investigations Report↗

Hydrologic conditions in the Klatt Bog area, Anchorage, Alaska

Klatt Bog is a 2.3 sq mi wetland in Anchorage, Alaska which provides habitat for many wildlife species but also offers potential sites for residential, commercial, and agricultural developments. Precipitation, the main source of water for the area, averages 15 in/yr; during the 1983 study period, precipitation was 12.16 inches. Estimates of evapotranspiration, considered to be the major component of water outflow, range from 10 to 20 inches. Surface runoff and groundwater outflow during 1983 are estimated to be 2.8 and < 0.2 inches, respectively. During summer, most of the runoff is derived from groundwater discharge near the upgradient eastern edge of the wetland. The wetland 's aquifer system is composed of fibrous peat which overlies a poorly permeable layer of silt and clay. The aquifer is recharged by infiltration of precipitation and inflow of groundwater from upland areas east of the wetland. During 1983 the water table was at or within 3 ft of land surface in most areas and its seasonal fluctuation was < 2 feet. Water collected from four shallow observation wells, two ponds, and two sites on a stream had concentrations of dissolved iron ranging from 2,300 to 6,100 micrograms/L. (Author 's abstract)

Water-Resources Investigations Report↗

Hydrologic conditions in Connors Bog Area, Anchorage, Alaska

Connors Bog is a wetland in Anchorage, Alaska, which provides a habitat for many wildlife species and is a popular area for driving off-road vehicles. A landfill, and residential and commercial developments are present in areas which were once wetland. The main source of water is precipitation, which averages about 15 in/yr. Estimates of evapotranspiration, which is the main component of water outflow, range from 10 to 20 in/yr. Minor amounts of groundwater and surface runoff flow into the area from the northeast and southwest and flow out of the area to the northwest and south. Within the wetland, water in peat and sand is unconfined and becomes more mineralized with depth. A leachate beneath and near an abandoned landfill is characterized by concentrations of dissolved solids, dissolved chloride, and total organics that are higher than those of the area 's natural water. The maximum lateral extent of detectable contamination in 1984 was < 500 ft from the landfill 's edge. Water in glacial deposits that underlie a poorly permeable layer of silt and clay is confined. A well completed in this confined aquifer yielded water that had a low concentration of dissolved solids, 150 mg/L. The potentiometric surface of this aquifer was about 20 ft lower than the water table during 1984. Connors Lake occupies a depression that extends below adjacent groundwater levels. The 40-acre lake has a maximum depth of about 9 ft and a low rate of biological production. The quality of water in the lake has not been adversely impacted by nearby residential development or landfill operations. Lake levels appear to be influenced by precipitation and adjacent groundwater levels. (Author 's abstract)

Water-Resources Investigations Report↗

Water-quality conditions and an evaluation of ground- and surface-water sampling programs in the Livermore-Amador Valley, California

A program to monitor the ground- and surface water quality in the Livermore-Amador Valley has been operated since 1976. As of 1982, this monitoring network consisted of approximately 130 wells, about 100 of which were constructed specifically for this program, and 9 surface water stations. Increased demand on the groundwater for municipal and industrial water supply in the past has caused a decline in water levels and a gradual buildup of salts from natural surface-water recharge and land disposal of treated wastewater from waste treatment plants. Results of this study identify the salt buildup to be the major problem with the groundwater quality. Established water quality objectives for dissolved solids are exceeded in 52 of 130 wells. Concentrations of dissolved nitrate are also in excess of basin objectives and health standards. Water quality in both surface and groundwater is highly variable areally. Magnesium to calcium magnesium bicarbonate groundwater are found in the areas where most of the high volume municipal wells are located. Large areas of sodium bicarbonate water occur in the northern part of the valley. Except for two stations on Arroyo Las Positas which has sodium chloride water, surface water is mixed-cation bicarbonate water. (USGS)

California↗