Geology ReportsSearch

Geology topics

D.P. Hammermeister

Publications and source records attributed to D.P. Hammermeister.

6 recordsLinked to original sources

Unsaturated flow in a centrifugal field: Measurement of hydraulic conductivity and testing of Darcy's Law

A method has been developed to establish steady state flow of water in an unsaturated soil sample spinning in a centrifuge. Theoretical analysis predicts moisture conditions in the sample that depend strongly on soil type and certain operating parameters. For Oakley sand, measurements of flux, water content, and matric potential during and after centrifugation verify that steady state flow can be achieved. Experiments have confirmed the theoretical prediction of a nearly uniform moisture distribution for this medium and have demonstrated that the flow can be effectively one-dimensional. The method was used for steady state measurements of hydraulic conductivity K for relatively dry soil, giving values as low as 7.6 × 10 −11 m/s with data obtained in a few hours. Darcy's law was tested by measuring K for different centrifugal driving forces but with the same water content. For the sand at a bulk density of 1.82 Mg/m 3 and 27% saturation, results were consistent with Darcy's law for K equal to 5.22 × 10 −10 m/s and forces ranging from 216 to 1650 times normal gravity.

Water Resources Research

Hydrologic data for Leviathan Mine and vicinity, Alpine County, California, 1981-83

The U.S. Geological Survey collected basic hydrologic and water-quality data during 1981-83 to facilitate the geohydrologic evaluation of the Leviathan Mine area and the design of a pollution-abatement project. Surface-water field data included one or more measurements of pH, water temperature, and specific conductance at 45 sites in and adjacent to the mine area. At nine of these sites, daily data on discharge, specific conductance, and water temperature were collected during parts of 1981-82 by using electronic monitor-recorder systems. Ground-water field data included one or more of the water-quality measurements listed above at 71 piezometers in the mine area. Borehole geophysical data included neutron-moisture, neutron-porosity, gamma-gamma density, natural gamma, and temperature logs at three sites. Mineralogic and hydrologic data were obtained for cores taken from nine test holes. One or more surface-water samples from 26 sites were analyzed for major cations, major anions, and a wide range of minor inorganic constituents. Single ground-water samples from 36 piezometers were analyzed for the same array of major and minor constituents. (USGS)

Open-File Report

Data from a solute transport experiment in the Leviathan Mine drainage, Alpine County, California, October 1982

A twenty-four hour injection of chloride and sodium was made into Leviathan Creek, Alpine County, California to aid interpretation of the coupled interactions between physical transport processes and geochemical reactions. Leviathan Creek was chosen because it receives acid mine drainage from Leviathan Mine, an abandoned open-pit sulfur mine. Water samples were collected at 15 sites along a 4.39 kilometer reach and analyzed for chloride, sodium, sulfate and fluoride. Dissolved concentrations are presented in tabular format and time-series plots. Duplicate samples were analyzed by two laboratories: the Central Laboratory, Denver, Colorado and a research laboratory in Menlo Park, California. A tabular comparison of the analyses and plots of the differences between the two laboratories is presented. Hydrographs and instantaneous discharge measurements are included. (USGS)

Open-File Report

Perched water tables on hillsides in western Oregon: I. Some factors affecting their development and longevity

Perched water tables on hillsides located on the western border of the Willamette Valley in Oregon in some cases have the potential to transport pollutants from either domestic or agricultural sources downslope to streams, ponds, or reservoirs, resulting in the deterioration of the quality of these waters. In this paper, some factors responsible for the development and longevity of these potentially problem-causing perched water tables on three hillsides were examined. Analyses of hydraulic conductivity data and the relationships between rainfall, soil water pressure potential, and time suggest that permeable rock below 110 cm rather than clayey B horizons is mainly responsible for the development of perched water tables on upper convex slope positions on two of these hillsides. The data also suggest that subsurface flow from the upper convex regions contributed significant amounts of water to the lower convex slope positions. Further, perched water tables developed more rapidly, to a greater extent, and lasted longer in upper horizons of a lower concave region of slope where a shallow perched water table was already present at the onset of rainfall. Finally, perched water tables did not develop in the upper horizons on a third hillside that had no impermeable regions in the soil or upper rock mantle.

Oregon

Perched water tables on hillsides in western Oregon: II. Preferential downslope movement of water and anions

Perched water tables on hillsides in western Oregon potentially provide a means by which pollutants from agricultural and domestic sources may enter surface waters and consequently degrade the quality of these waters. This paper reports the results of experiments which were carried out to investigate the flow of solutes and water from buried line sources in and above perched water tables on three different hillsides in western Oregon. In the saturated soil and rock mantles of two hillsides, evidence suggests that water and solutes flow preferentially through large continuous voids. The evidence includes the very high maximum rate of anion movement downslope, the failure of pore velocities calculated from Darcy's Law to predict the rate and direction of anion movement, the short time before high levels of anions are detected downslope, and the spatial variability in the maximum rates of anion movement over the depth and width of sites. On the third hillside, tracer anion movement and soil water pressure measurements indicate that preferential flow occurs through large continuous pores during heavy rainfall while the surrounding soil and rock mantle remains unsaturated. Finally, experiments with Rodamine WT dye show that a variety of continuous voids of different origins and sizes conduct water and solutes preferentially in the soil and upper regions of rock on these hillsides.

Oregon