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K. C. Glover

Publications and source records attributed to K. C. Glover.

8 recordsLinked to original sources
USGS1988

A finite-element model for simulating hydraulic interchange of surface and ground water

A model was developed to be useful for predicting changes in streamflow as a result of groundwater pumping. The stream aquifer model is especially useful for simulating streams that flow intermittently owing to leakage to the aquifer or diversion for irrigation or streams that become perched owing to declining hydraulic head in the aquifer. The model couples the equation of two-dimensional groundwater flow with the kinematic equations of one-dimensional open-channel flow. Darcy 's law for vertical flow through a semipermeable streambed is used to couple the groundwater flow and streamflow equations. The equations of flow are approximated numerically by the finite-element method. A listing of the Fortran program that solves the equations of flow , and a description of data-input formats are given in the report. The program can simulate a variety of hydrologic characteristics including perched streams, streamflow diversions , springs, recharge from irrigated acreage, and evapotranspiration from the water table and phreatophytes. Time-dependent boundary conditions can be simulated. The program can be modified easily to simulate unconfined aquifers and aquifers with variable directions of anisotropy. (USGS)

Water-Resources Investigations Report↗
USGS1987

A dual-porosity model for simulating solute transport in oil shale

A model is described for simulating three-dimensional groundwater flow and solute transport in oil shale and associated geohydrologic units. The model treats oil shale as a dual-porosity medium by simulating flow and transport within fractures using the finite-element method. Diffusion of solute between fractures and the essentially static water of the shale matrix is simulated by including an analytical solution that acts as a source-sink term to the differential equation of solute transport. While knowledge of fracture orientation and spacing is needed to effectively use the model, it is not necessary to map the locations of individual fractures. The computer program listed in the report incorporates many of the features of previous dual-porosity models while retaining a practical approach to solving field problems. As a result the theory of solute transport is not extended in any appreciable way. The emphasis is on bringing together various aspects of solute transport theory in a manner that is particularly suited to the unusual groundwater flow and solute transport characteristics of oil shale systems. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1986

Leachate migration from an in situ oil-shale retort near Rock Springs, Wyoming

Geohydrologic factors influencing leachate movement from an in situ oil shale retort near Rock Springs, Wyoming, were investigated by developing models of groundwater flow and solute transport. Leachate, indicated by the conservative ion thiocyanate, has been observed 1/2 mi downgradient from the retort. The contaminated aquifer is part of the Green River Formation and consists of thin, permeable layers of tuff and sandstone interbedded with oil shale. Most solute migration has occurred in an 8-ft sandstone at the top of the aquifer. Groundwater flow in the study area is complexly 3-D and is characterized by large vertical variations in hydraulic head. The solute transport model was used to predict the concentration of thiocyanate at a point where groundwater discharges to the land surface. Leachates with peak concentrations of thiocyanate--45 mg/L or approximately one-half the initial concentration of retort water--were estimated to reach the discharge area during January 1985. Advantages as well as the problems of site specific studies are described. Data such as the distribution of thin permeable beds or fractures may introduce an unmanageable degree of complexity to basin-wide studies but can be incorporated readily in site specific models. Solute migration in the study area primarily occurs in thin permeable beds rather than in oil shale strata. Because of this behavior, leachate traveled far greater distances than might otherwise have been expected. The detail possible in site specific models permits more accurate prediction of solute transport than is possible with basin-wide models. A major problem in site specific studies is identifying model boundaries that permit the accurate estimation of aquifer properties. If the quantity of water flowing through a study area cannot be determined prior to modeling, the hydraulic conductivity and groundwater velocity will be estimated poorly. (Author's abstract)

Wyoming↗
USGS1984

Storage analyses for ephemeral streams in semiarid regions

A model has been developed for determining the probability of a reservoir being unable to provide a specified downstream water supply. By applying the model with a number of assumed storage capacities, the long-term water supply potential of a stream below a reservoir can be evaluated. Previous methods for determining available water supply from streamflow records using a reservoir storage analysis have met with limited success in semiarid regions. The shortcomings are due to the failure of the methods to account for zero-flow periods and the high day-to-day variability of discharge of many streams. The reservoir storage model presented in this report is designed to account for these streamflow characteristics. Reservoir inflow, outflow, and evaporation are modeled as varying daily, and values of storage probability are adjusted for zero-flow periods. (USGS)

Water-Resources Investigations Report↗
USGS1982

Digital model of the Bates Creek alluvial aquifer near Casper, Wyoming

A digital model was used to simulate ground-water flow within the Bates Creek alluvial aquifer, southwest of Casper, Wyoming. Hydrologic data collected during 1977 and 1978 were used to develop the flow model under steady-state and transient conditions. Three scenarios for operating the stream-aquifer system were evaluated with the digital model. The scenarios represent no ground-water pumping, pumping by all existing wells , and pumping by all existing and proposed wells. The model simulations used average values of stream discharge, ground-water pumpage and water use as input parameters. A decrease in the quantitity of ground-water discharge to Bates Creek is predicted to occur through 1988 as a result of pumping. The magnitude and timing of the predicted decrease in ground-water discharge may differ from actual ground-water discharge if hydrologic conditions through 1988 vary significantly from the averaged input values used in the simulations. (USGS)

Water-Resources Investigations Report↗