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W. B. Scott

Publications and source records attributed to W. B. Scott.

7 recordsLinked to original sources

Hydrologic activities of the U.S. Geological Survey in support of the Radionuclide Migration Program, Nevada Test Site and vicinity, Nye County, Nevada, fiscal year 1987

Hydrologic activities during the 1987 fiscal year by the U.S. Geological Survey in support of the Radionuclide Migration Program at the Nevada Test Site are summarized. These activities included monitoring groundwater levels; compiling and entering geohydrologic data into the U.S. Geological Survey computerized groundwater database; providing technical support to the Radionuclide Migration Committee and the Containment Evaluation Panel; and the planning, drilling, and sampling of the UE20n-1 hole. Groundwater levels were monitored continuously at 2 wells and intermittently at 36 selected wells, test holes, and emplacement holes. Selected monthly water-level measurements are listed for the continuously monitored wells and intermittent measurements are listed for the selected wells, test holes, and emplacement holes. Progress continued on four groundwater hydrology reports of the Nevada Test Site area. (Thacker-USGS, WRD)

Open-File Report↗

Three-dimensional model simulation of transient ground-water flow in the Albuquerque-Belen Basin, New Mexico

A three-dimensional digital model that simulates transient flow in the alluvial aquifer system underlying the Albuquerque-Belen Basin, New Mexico, was constructed as part of a regional aquifer study of the southwest alluvial basins. The model simulates hydraulic heads and changes in hydraulic heads for 1907 to 1979. Hydraulic-conductivity values used in the accepted model range from 0.25 ft/day in part of the Santa Fe Group to 50 ft/day in the fluvial deposits in the Rio Grande flood plain. The majority of the basin-fill material of the Santa Fe group of Tertiary and Quaternary age was modeled as having a horizontal hydraulic conductivity of either 30 or 40 ft/day. The simulated specific storage of the aquifer was 0.000001/ft and the simulated specific yield was 0.10. The aquifer was simulated as being vertically anisotropic with a ratio of vertical to horizontal hydraulic conductivity of 1:500. Simulations for 1976-79 indicated that of the 100,000 acre-ft of groundwater withdrawn annually from the basin-fill deposits outside of the Rio Grande flood plain, 68% was obtained from recharge around the basin margin, depletion of streams that are tributary to the Rio Grande, and the stream-aquifer system in the Rio Grande flood plain. Depletion of aquifer storage accounted for 25% of the groundwater supply to wells outside of the flood plain, and the remaining 7% was obtained by induced groundwater inflow from the Santo Domingo Basin. The model displayed an acceptable performance throughout the period of simulation. However, by the end of the simulation period, 1979, the portrayal of the Rio Grande flood-plain system as a specified hydraulic-head boundary was having adverse effects on the simulation. (Author 's abstract)

Water-Resources Investigations Report↗

Three-dimensional model simulation of steady-state ground-water flow in the Albuquerque-Belen Basin, New Mexico

As part of the Southwest Alluvial Basins study, model was constructed to simulate the alluvial aquifer system underlying the Albuquerque-Belen Basin. The model was used to simulate the steady-state flow condition assumed to have existed prior to 1960. Until this time there apparently were no long-term groundwater level changes of a significant magnitude outside the immediate vicinity of Albuquerque. Therefore, the construction of a steady-state flow model of the aquifer system based on reported hydrologic data predating 1960 was justified. During construction of the steady-state model, simulated hydraulic conductivity values were adjusted, within acceptable physical limits, until a best fit between measured or reported and computed heads at 34 control wells was achieved. The modeled area was divided into six sub-areas, or zones, within each of which hydraulic conductivity was assumed to be uniform. The model consisted of six layers for each of which simulated transmissivity was proportional to the layer thickness. Adjustments to simulated hydraulic conductivity values in the different zones resulted in final values that ranged from a low of 0.25 ft/day in the west to 50 ft/day in the eastern part of the basin. The error of the simulation, defined as the absolute difference between the computed and the measured or reported water level at the corresponding point in the physical system being modeled, ranged from 0.6 ft to 36 ft, with an average of 14.6 ft for the 34 control wells. (Author 's abstract)

Water-Resources Investigations Report↗

Planning report for the southwest alluvial basins (east) regional aquifer-system analysis, parts of Colorado, New Mexico, and Texas

The study of the Southwest alluvial basins (east) will involve an analysis of the regional aquifer system in parts of Colorado, New Mexico, and Texas. This area has been divided into 22 basins. The study of the alluvial aquifer-system will be made in the following stages: (1) project planning, (2) literature searches, (3) compiling existing data, (4) data collection, (5) basin modeling, (6) regional aquifer modeling, and (7) reports. The regional aquifer study will be accomplished through studying each of the 22 basins. Data compilation and limited data collection will be part of each basin study. Digital computer models will be made for those basins where data are sufficient. A regional aquifer model will be developed from the basin models. In addition to this report, there will be basin hydrology reports and the final regional report. Included in the final report will be a description of the regional hydrology and geology. (USGS)

Open-File Report↗

Hydraulic conductivity and water quality of the shallow aquifer, Palm Beach County, Florida

Subsurface geophysical logs were correlated with logs of drill cuttings to determine the permeability of selected zones of the shallow aquifer, Palm Beach County, Fla. The hydraulic conductivity of the aquifer is estimated to range from 1 to 130 feet per day, based on lithology and physical properties. The yield of wells penetrating this aquifer ranges from 100 to more than 1,000 gallons per minute. Water samples were collected from different depths throughout the county and analyzed for chemical constituents. Stiff diagrams illustrate the changes in types of water by depth and area. Water of suitable quality is in the eastern parts of the county. In this area the aquifer is the thickest and most permeable. The concentration of chemical constituents in the water increase in a westerly direction. The water in the western parts of the county is unsuitable for most purposes. (Woodard-USGS)

Florida↗

Saltwater intrusion in the shallow aquifer in Martin and Palm Beach counties, Florida

Urban growth has been rapid in recent years in Palm Beach and Martin Counties, Fla. The withdrawal of large quantities of fresh ground water in the vicinity of the coast has reduced or locally reversed the natural seaward hydraulic gradient and, in places, allowed saltwater to advance landward in the aquifer, displacing freshwater. Maps show the position of the saltwater front in eight urban areas adjacent to the coast. The saltwater front, as shown on the profiles, is based on a chloride concentration of 250 mg/liter which is recommended as a limit for water that is considered potable. The chloride concentration of native freshwater almost always is less than 50 mg/liter in the coastal aquifer. (Woodard-USGS)

Florida↗

The occurrence of the longjaw cisco, Leucichthys alpenae , in Lake Erie

The longjaw cisco, Leucichthys alpenae , is shown to be a species new to the Lake Erie fauna. The taxonomic work on Lake Erie ciscoes is reviewed. Thirty three specimens of L . alpenae taken in 1946, 1947 and 1957 are compared morphometrically with Leucichthys artedi of Lake Erie, the only other cisco species in the lake. L . alpenae has a longer and deeper head, longer maxillary and fewer gill rakers. L . alpenae is more distinct from L . artedi in Lake Huron than in Lake Erie. The rate of growth of L . alpenae in Lake Erie compares favourably with that in Lake Michigan.

Journal of the Fisheries Research Board of Canada↗