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Geoffrey W. Freethey

Publications and source records attributed to Geoffrey W. Freethey.

15 recordsLinked to original sources

Simulation of ground-water flow and solute transport in the Glen Canyon aquifer, East-Central Utah

The extraction of methane from coal beds in the Ferron coal trend in central Utah started in the mid-1980s. Beginning in 1994, water from the extraction process was pressure injected into the Glen Canyon aquifer. The lateral extent of the aquifer that could be affected by injection is about 7,600 square miles. To address regional-scale effects of injection over a decadal time frame, a conceptual model of ground-water movement and transport of dissolved solids was formulated. A numerical model that incorporates aquifer concepts was then constructed and used to simulate injection. The Glen Canyon aquifer within the study area is conceptualized in two parts—an active area of ground-water flow and solute transport that exists between recharge areas in the San Rafael Swell and Desert, Waterpocket Fold, and Henry Mountains and discharge locations along the Muddy, Dirty Devil, San Rafael, and Green Rivers. An area of little or negligible ground-water flow exists north of Price, Utah, and beneath the Wasatch Plateau. Pressurized injection of coal-bed methane production water occurs in this area where dissolved-solids concentrations can be more than 100,000 milligrams per liter. Injection has the potential to increase hydrologic interaction with the active flow area, where dissolved-solids concentrations are generally less than 3,000 milligrams per liter. Pressurized injection of coal-bed methane production water in 1994 initiated a net addition of flow and mass of solutes into the Glen Canyon aquifer. To better understand the regional scale hydrologic interaction between the two areas of the Glen Canyon aquifer, pressurized injection was numerically simulated. Data constraints precluded development of a fully calibrated simulation; instead, an uncalibrated model was constructed that is a plausible representation of the conceptual flow and solute-transport processes. The amount of injected water over the 36-year simulation period is about 25,000 acre-feet. As a result, simulated water levels in the injection areas increased by 50 feet and dissolved-solids concentrations increased by 100 milligrams per liter or more. These increases are accrued into aquifer storage and do not extend to the rivers during the 36-year simulation period. The amount of change in simulated discharge and solute load to the rivers is less than the resolution accuracy of the numerical simulation and is interpreted as no significant change over the considered time period.

Utah↗

Ground-water hydrology of Dugway Proving Ground and adjoining area, Tooele and Juab counties, Utah

Dugway Proving Ground (DPG) is a U.S. Department of Defense chemical, biological, and explosives testing facility in northwestern Utah. The facility includes about 620 mi 2 in Tooele County. The town of Dugway, referred to as English Village, is the administrative headquarters for the military facility, the primary residential area, and community center. The English Village area is located at the southern end of Skull Valley and is separated from the Fries area by a surface-water divide. Most of the facility is located just to the west of Skull Valley in Government Creek Valley, Dugway Valley, and the Great Salt Lake Desert (fig. 1).

Utah↗

Maps summarizing geohydrologic information in an area of salt-water disposal, eastern Altamont-Bluebell petroleum field, Uinta Basin, Utah

In the Altamont-Bluebell Petroleum Field within the Uinta Basin of Utah, saline oil-production water is being injected into the Duchesne River Formation. On the basis of geohydrologic information, a qualitative assessment of the possible effects of this injection indicates that fresh groundwater in certain areas of the Duchesne River formation may be more susceptible than water in other areas to becoming mixed with injected oil-production water. The reason for this possible mixing is because these areas containing the susceptible groundwater lack a thick shale layer above the disposal zone, as indicated in geophysical logs. In other areas, naturally occurring moderately saline water exists at shallow depths and may be withdrawn from water wells completed more than 200 ft below land surface. Additional geohydrologic information will need to be collected to allow investigators to make a quantitative determination of the rate of horizontal and vertical migration of injected oil-production water within and above the disposal zone.

Utah↗

Geohydrology of Mesozoic rocks in the upper Colorado River basin in Arizona, Colorado, New Mexico, Utah, and Wyoming, excluding the San Juan Basin

The purpose of this report is to provide a quantitative analysis of the occurrence, movement, and quality of water and the hydrologic characteristics of aquifers and confining units in the Mesozoic rocks of the Upper Colorado River Basin. The analysis is regional in scope and, hence, does not address site-specific problems caused by intricate localized quality, lithologic, or structural discontinuities. The report is intended to answer questions about the lateral flow of ground water from recharge to discharge areas, its vertical movement between aquifer systems, and the general water-yielding properties of aquifers. Because the investigation was regional in scope, analyses of recharge, ground-water movement, discharge, and storage were based on data and interpretations from the results of previous investigations and existing files from government and private sources. Analyses of hydrologic properties and water quality were based largely on the same sources but were supplemented with a small quantity of newly collected data for areas for which this type of information was lacking.

Arizona, Colorado, New Mexico, Utah, Wyoming↗

General hydrogeology of the aquifers of Mesozoic age, Upper Colorado River Basin - excluding the San Juan Basin - Colorado, Utah, Wyoming, and Arizona

The objective of the Upper Colorado Regional Aquifer Systems Analyses (RASA) project is to assess quantitatively the occurrence, movement, and availability of water stored in rock formations underlying the basin. This is one of a series of preliminary reports that describe what is currently known (1984) about the geometry and hydrologic properties of the aquifer systems, and the chemistry of the water in known or potential aquifers. This report provides the foundation needed for the assessment of the ground-water resources of the region. The report describes only part of the hydrologic system; that is, formations of Mesozoic age. Younger and older formations significant to the hydrologic system are described in other reports.

Arizona, Colorado, Utah, Wyoming↗

Models, data available, and data requirements for estimating the effects of injecting saltwater into disposal wells in the greater Altamont-Bluebell oil and gas field, northern Uinta Basin, Utah

Permits for disposing of salty oil-production water have been issued for 19 wells in the Greater Altamont-Bluebell field. During 1986 more than 500 million gallons of production water were injected into the Duchesne River, Uinta, and Green River Formations through 18 of these wells. The physical and chemical effects of injecting this water into aquifers containing potable water are poorly understood. Interfingering and the structural configuration of these formations add complexity to the description of the geometry and hydrogeology of the ground-water system. A preliminary assessment of the problem indicates that numerical modeling may offer a method of determining the effects of injection. Modeling possibilities include variable-density, three-dimensional flow, sectionaltransport, and areal-transport models. Data needed to develop these models can be derived from a synthesis of geologic, hydrologic, and hydrochemical data already available in the files of State and Federal agencies, oil companies, and private companies. Results from each modeling phase would contribute information for implementing the following phase. The result will be a better understanding of how water moves naturally through the groundwater system, the extent of alterations of both vertical and horizontal flow near the disposal wells, and an overall concept of the effects of deep injection on near-surface aquifers.

Utah↗

Water resources of the Cook Inlet Basin, Alaska

Ground-water and surface-water systems of Cook Inlet basin, Alaska, are analyzed. Geologic and topographic features that control the movement and regional availability of ground water are explained and illustrated. Five aquifer systems beneath the most populous areas are described. Estimates of ground-water yield were determined for the region by using ground-water data for the populated areas and by extrapolating known subsurface conditions and interpreting subsurface conditions from surficial features in the other areas. Area maps of generalized geology, Quaternary sediment thickness, and general availability of ground water are shown. Surface-water resources are summarized by describing how basin characteristics affect the discharge in streams. Seasonal trend of streamflow for three types of streams is described. Regression equations for 4 streamflow characteristics (annual, monthly minimum, and maximum discharge) were obtained by using gaging station streamflow characteristics and 10 basin characteristics. In the 24 regression equations presented, drainage area is the most significant basin characteristic, but 5 others are used. Maps of mean annual unit runoff and minimum unit yield for 7 consecutive days with a recurrence interval of 10 years are shown. Historic discharge data at gaging stations is tabulated and representative low-flow and flood-flow frequency curves are shown. (USGS)

Hydrologic Atlas↗

Water resources of the Cordova area, Alaska

This report is a compilation of ground-water, surface-water, and water-quality data collected by the U.S. Geological Survey, Water Resources Division on Eyak Lake and Power Creek, near Cordova, and wells in and near Cordova, Alaska. Many of these data were collected as part of a cooperative program with the city of Cordova. The purpose of this report is to present the data in a concise format for interested parties. Cordova is on the southeast shore of Orca Inlet in Prince William Sound (lat 60°33' N.; long 145°45' W.) at an altitude of approximately 90 feet (fig. 7). The limited development has occurred along the north shore of the west arm of Eyak Lake. The current population of Cordova is about 1,800. Commercial fishing and fish processing form the economic base for the community.

Alaska↗

Preliminary report on water availability in the lower Ship Creek basin, Anchorage, Alaska : with special reference to the fish hatchery on Fort Richardson and a proposed fish-hatchery site near the Elmendorf Air Force base power-plant

The availability of surface water and shallow ground water in the lower Ship Creek basin, Anchorage, Alaska, was examined using 28 years of streamflow records and well logs. Streamflow gains and losses were estimated from 23 seepage investigations made since May 1957. A contour map of the top of the principal confining stratum and an isopach map of the saturated material were made in order to locate areas with the greatest potential for unconfined ground-water development. An adequate supply of water needed for further development of the Fort Richardson fish hatchery probably is available downstream from that site from unconfined ground-water sources. Unconfined ground water upstream from that site probably would not fulfill the water requirements of the hatchery. Additional aquifer testing is needed to verify these predictions. At the proposed fish-hatchery site on Elmendorf Air Force Base it probably is not possible to withdraw the required water either from a system of wells in the unconfined ground-water zone or from Ship Creek during periods of low flow. Two areas upstream from the site offer better potential for unconfined ground-water development; however, exploratory test wells and aquifer testing will be required to define areas of greater saturated thickness and effects of withdrawing the water needed.

Alaska↗