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Sample records for additional ground-water withdrawals

  1. Update to the Ground-Water Withdrawals Database for the Death Valley REgional Ground-Water Flow System, Nevada and California, 1913-2003

    SciTech Connect

    Michael T. Moreo; and Leigh Justet

    2008-07-02

    Ground-water withdrawal estimates from 1913 through 2003 for the Death Valley regional ground-water flow system are compiled in an electronic database to support a regional, three-dimensional, transient ground-water flow model. This database updates a previously published database that compiled estimates of ground-water withdrawals for 1913–1998. The same methodology is used to construct each database. Primary differences between the 2 databases are an additional 5 years of ground-water withdrawal data, well locations in the updated database are restricted to Death Valley regional ground-water flow system model boundary, and application rates are from 0 to 1.5 feet per year lower than original estimates. The lower application rates result from revised estimates of crop consumptive use, which are based on updated estimates of potential evapotranspiration. In 2003, about 55,700 acre-feet of ground water was pumped in the DVRFS, of which 69 percent was used for irrigation, 13 percent for domestic, and 18 percent for public supply, commercial, and mining activities.

  2. Update to the Ground-Water Withdrawals Database for the Death Valley Regional Ground-Water Flow System, Nevada and California, 1913-2003

    USGS Publications Warehouse

    Moreo, Michael T.; Justet, Leigh

    2008-01-01

    Ground-water withdrawal estimates from 1913 through 2003 for the Death Valley regional ground-water flow system are compiled in an electronic database to support a regional, three-dimensional, transient ground-water flow model. This database updates a previously published database that compiled estimates of ground-water withdrawals for 1913-1998. The same methodology is used to construct each database. Primary differences between the 2 databases are an additional 5 years of ground-water withdrawal data, well locations in the updated database are restricted to Death Valley regional ground-water flow system model boundary, and application rates are from 0 to 1.5 feet per year lower than original estimates. The lower application rates result from revised estimates of crop consumptive use, which are based on updated estimates of potential evapotranspiration. In 2003, about 55,700 acre-feet of ground water was pumped in the DVRFS, of which 69 percent was used for irrigation, 13 percent for domestic, and 18 percent for public supply, commercial, and mining activities.

  3. 18 CFR 430.19 - Ground water withdrawal metering, recording, and reporting.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 2 2014-04-01 2014-04-01 false Ground water withdrawal metering, recording, and reporting. 430.19 Section 430.19 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION SPECIAL REGULATIONS GROUND WATER PROTECTION AREA: PENNSYLVANIA § 430.19 Ground water withdrawal metering,...

  4. 18 CFR 430.19 - Ground water withdrawal metering, recording, and reporting.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Ground water withdrawal... DELAWARE RIVER BASIN COMMISSION SPECIAL REGULATIONS GROUND WATER PROTECTION AREA: PENNSYLVANIA § 430.19 Ground water withdrawal metering, recording, and reporting. (a) Each person, firm, corporation, or...

  5. 18 CFR 430.19 - Ground water withdrawal metering, recording, and reporting.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 2 2012-04-01 2012-04-01 false Ground water withdrawal metering, recording, and reporting. 430.19 Section 430.19 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION SPECIAL REGULATIONS GROUND WATER PROTECTION AREA: PENNSYLVANIA § 430.19 Ground water withdrawal metering,...

  6. 18 CFR 430.19 - Ground water withdrawal metering, recording, and reporting.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 2 2013-04-01 2012-04-01 true Ground water withdrawal metering, recording, and reporting. 430.19 Section 430.19 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION SPECIAL REGULATIONS GROUND WATER PROTECTION AREA: PENNSYLVANIA § 430.19 Ground water withdrawal metering,...

  7. Ground-Water-Withdrawal Component of the Michigan Water-Withdrawal Screening Tool

    USGS Publications Warehouse

    Reeves, Howard W.; Hamilton, David A.; Seelbach, Paul W.; Asher, A. Jeremiah

    2009-01-01

    A water-withdrawal assessment process and Internet-based screening tool have been developed to evaluate proposed new or increased high-capacity water withdrawals in Michigan. Michigan legislation defines high capacity withdrawals as those capable of removing an average of 100,000 gallons per day for a consecutive 30-day period. This report describes the ground-water component of the screening tool, provides background information used to develop the screening tool, and documents how this component of the screening tool is implemented. The screening tool is based on application of an analytical model to estimate streamflow depletion by a proposed pumping well. The screening tool is designed to evaluate intermittent pumping, to account for the dynamics of stream-aquifer interaction, and to apportion streamflow depletion among neighboring streams. The tool is to be used for an initial screening of a proposed new or increased high-capacity withdrawal in order to identify withdrawals that may cause adverse resource impacts. The screening tool is not intended to be a site-specific design tool. Results of an example application of the screening tool in Kalamazoo County, Mich., are compared to streamflow depletion estimated by use of a regional ground-water-flow model to demonstrate its performance.

  8. Simulated effects of alternative withdrawal strategies on ground-water-flow patterns, New Jersey Pinelands

    USGS Publications Warehouse

    Modica, Edward

    1996-01-01

    A steady-state, three-dimensional ground-water- flow model of the unconfined part of the Kirkwood- Cohasey aquifer system beneath the upper parts of the Rancocas Creek and Wading River Basins in the New Jersey Pinelands was developed to (1) define ground-water-flow patterns and residence times in an aquifer system typical of the New Jersey Coastal Plain and (2) demonstrate the effects of alternative withdrawal strategies of ground- water-flow patterns and streams. Ground-water flow near the McDonald's-Middle Branch area was analyzed by using a particle tracker to demonstrate the effects of three hypothetical withdrawal scenarios on the configurations of source areas of ground-water flow to withdrawal wells, streams, and other discharge outlets in the Kirkwood-Cohansey aquifer system. Under natural conditions, most ground-water discharge to streams and wetlands. Ground-water residence times ranged from slightly greater than zero to about 200 years. Much of the ground water remained in the system for less than 20 years because it discharged to streams. Residence times of ground water were reduced significantly by persistent withdrawals. The configurations of source areas of flow to local stream systems and to the Piney Point aquifer are affected by the location of a withdrawal well. Results of withdrawal simulations indicate that well-location strategies applied in the Kirkwood-Cohansey aquifer system can alleviate the adverse effects of withdrawals on streams and that large-scale regional withdrawals in confined aquifers can adversely effect streams although the effects are dispersed over numerous streams.

  9. 18 CFR 430.19 - Ground water withdrawal metering, recording, and reporting.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 2 2011-04-01 2011-04-01 false Ground water withdrawal metering, recording, and reporting. 430.19 Section 430.19 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION SPECIAL REGULATIONS GROUND WATER PROTECTION AREA: PENNSYLVANIA §...

  10. Land subsidence caused by ground water withdrawal in urban areas

    USGS Publications Warehouse

    Holzer, T.L.; Johnson, A.I.

    1985-01-01

    At least eight urban areas in the world have encountered significant economic impact from land subsidence caused by pumping of ground water from unconsolidated sediment. The areas, most of which are coastal, include Bangkok, Houston, Mexico City, Osaka, San Jose, Shanghai, Tokyo, and Venice. Flooding related to decreased ground elevation is the principal adverse effect of the subsidence. Lesser effects include regional tilting, well-casing failures, "rising" buildings, and ground failure or rupture. Subsidence of most of these urban areas began before the phenomenon was discovered and understood. Thus, the subsidence problems were unanticipated. Methods to arrest subsidence typically have included control of ground water pumping and development of surface water to offset the reductions of ground water pumping. Ground water recharge has also been practiced. Areas threatened by flooding have been protected by extensive networks of dikes and sea walls, locks, and pumping stations to remove storm runoff. ?? 1985 D. Reidel Publishing Company.

  11. Simulation of the Ground-Water Flow System in 1992, and Simulated Effects of Projected Ground-Water Withdrawals in 2020 in the New Jersey Coastal Plain

    USGS Publications Warehouse

    Gordon, Alison D.

    2003-01-01

    In 1992, ground-water withdrawals from the unconfined and confined aquifers in the New Jersey Coastal Plain totaled about 300 million gallons per day, and about 70 percent (200 million galllons per day) of this water was pumped from confined aquifers. The withdrawals have created large cones of depression in several Coastal Plain aquifers near populated areas, particularly in Camden and Ocean Counties. The continued decline of water levels in confined aquifers could cause saltwater intrusion, reduction of stream discharge near the outcrop areas of these aquifers, and depletion of the ground-water supply. Because of this, withdrawals from wells located within these critical areas have been reduced in the Potomac-Raritan-Magothy aquifer system, the Englishtown aquifer system, and the Wenonah-Mount Laurel aquifer. A computer-based model that simulates freshwater and saltwater flow was used to simulate transient ground-water flow conditions and the location of the freshwater-saltwater interface during 1989-92 in the New Jersey Coastal Plain. This simulation was used as the baseline for comparison of water levels and flow budgets. Four hypothetical withdrawal scenarios were simulated in which ground-water withdrawals were either increased or decreased. In scenario 1, withdrawals from wells located within critical area 2 in the Potomac-Raritan-Magothy aquifer system were reduced by amounts ranging from 0 to 35 percent of withdrawals prior to 1992. Critical area 2 is mainly located in Camden County, and most of Burlington and Gloucester Counties. With the reductions, water levels recovered about 30 feet in the regional cone of depression centered in Camden County in the Upper Potomac-Raritan-Magothy aquifer and by 20 ft in the Lower and Middle Potomac-Raritan-Magothy aquifers. In scenarios 2 to 4, withdrawals projected for 2020 were input to the model. In scenario 2, withdrawal restrictions within the critical areas were imposed in the Potomac-Raritan-Magothy aquifer

  12. Faulting arrested by control of ground-water withdrawal in Houston, Texas.

    USGS Publications Warehouse

    Holzer, T.; Gabrysch, R.K.; Verbeek, E.R.

    1983-01-01

    More than 86 historically active faults with an aggregate length of 150 miles have been identified within and adjacent to the Houston, Texas, metropolitan area. Although scarps of these faults grow gradually and without causing damaging earthquakes, historical fault offset has cost millions of dollars in damage to houses and other buildings, utilities, and highways that were built on or across the faults. The historical fault activity results from renewed movement along preexisting faults and appears to be caused principally by withdrawal of ground water for municipal, industrial, and agricultural uses in the Houston area. Approximately one-half of the area's water supply is obtained from local ground water. Monitoring by the US Geological Survey of heights of fault scarps indicates that many of the scarps have recently stopped increasing in height. The area where faulting has ceased coincides with the area where ground-water pumping was cut back in the mid-1970s to slow the damage caused by land subsidence along Galveston Bay and the Houston Ship Channel. Thus, it appears that efforts to halt land subsidence in the coastal area have provided the additional benefit of arresting damaging surface faulting. -from Authors

  13. Effects of Irrigation, Drought, and Ground-Water Withdrawals on Ground-Water Levels in the Southern Lihue Basin, Kauai, Hawaii

    USGS Publications Warehouse

    Izuka, Scot K.

    2006-01-01

    A numerical ground-water-flow model was used to investigate the effects of irrigation on ground-water levels in the southern Lihue Basin, Kauai, Hawaii, and the relation between declining ground-water levels observed in the basin in the 1990s and early 2000s and concurrent drought, irrigation reduction, and changes in ground-water withdrawal. Results of steady-state model simulations indicate that changing from pre-development to 1981 irrigation and ground-water-withdrawal conditions could, given enough time for steady state to be achieved, raise ground-water levels in some areas of the southern Lihue Basin by as much as 200 feet, and that changing from 1981 to 1998 irrigation and ground-water-withdrawal conditions could lower ground-water levels in some areas by as much as 100 feet. Transient simulations combining drought, irrigation reduction, and changes in ground-water withdrawal show trends that correspond with those observed in measured water levels. Results of this study indicate that irrigation reduction was the primary cause of the observed decline in ground-water-levels. In contrast, ground-water withdrawal had a long-duration but small-magnitude effect, and drought had a widespread, high-magnitude but short-duration effect. Inasmuch as irrigation in the future is unlikely to return to the same levels as during the period of peak sugarcane agriculture, the decline in ground-water levels resulting from the reduction and ultimate end of sugarcane irrigation can be considered permanent. Assuming that irrigation does not return to the southern Lihue Basin and that, on average, normal rainfall persists and ground-water withdrawal remains at 1998 rates, model projections indicate that average ground-water levels in the Kilohana-Puhi area will continue to recover from the drought of 1998-2002 and eventually rise to within about 4 feet of the pre-drought conditions. Long-term climate trends, increases in ground-water withdrawal, or other factors not simulated in

  14. Ground-water withdrawals from the Coastal Plain of New Jersey, 1956-1980

    USGS Publications Warehouse

    Vowinkel, E.F.

    1984-01-01

    Withdrawals and site data for wells with a pump capacity of 100 ,000 gallons per day or greater in the Coastal Plain of New Jersey are stored in computer files for 1956-80. The data are aggregated by computer into tables, graphs and maps to show the distribution of ground-water withdrawals. Withdrawals are reported by type of use and aquifer for each county in the Coastal Plain. Public-supply wells withdraw the largest quantity of ground water in the Coastal Plain, followed by industrial and agricultural wells. In 1980 public-supply withdrawals were about 280 million gallons per day; the maximum monthly rate was about 355 million gallons per day in July, and the lowest was about 215 million gallons per day in February. Average industrial withdrawals were about 65 million gallons per day. Ground-water withdrawals used for agriculture vary significantly during the year. In 1980, about 75 percent of the agricultural withdrawals occurred from June through September. Several aquifers are used as sources of water supply in the Coastal Plain. Five regional aquifers are the major sources of water for public-supply, industrial, or agricultural use. In decreasing order of withdrawals in 1980, in million gallons per day, they are: The Potomac-Raritan-Magothy aquifer system, 243; Kirkwood-Cohansey aquifer system, 70; Atlantic City 800-foot sand, 21; Englishtown aquifer, 12; and the Wenonah-Mount Laurel aquifer system, 5. (USGS)

  15. Effects of Ground-Water Withdrawal on Kaunakakai Stream Environmental Restoration Plan, Moloka`i, Hawai`i

    USGS Publications Warehouse

    Oki, Delwyn S.

    2007-01-01

    The U.S. Army Corps of Engineers, in cooperation with the County of Maui Department of Public Works and Environmental Management, has proposed to construct 2.75 acres of shallow ponds and mudflats near the mouth of Kaunakakai Stream, Moloka`i, Hawai`i to restore habitat for the endangered native Hawaiian Stilt. Kaunakakai Stream is ephemeral upstream from the habitat-restoration site. Where the pond and wetland bottoms are below the water table, the ponds and wetland will be sustained by ground-water discharge during dry-weather conditions. Because ground water is the main source of water for the proposed ponds and wetland, a reduction of ground-water levels and discharge near the mouth of Kaunakakai Stream will have an effect on the availability of habitat. In response to concerns about the possible effects of ground-water withdrawal on the habitat restoration project near the mouth of Kaunakakai Stream, the U.S. Geological Survey undertook the present investigation to estimate, using an existing numerical ground-water-flow model, the changes in ground-water level and coastal discharge caused by redistributed and additional ground-water withdrawals. Steady-state water-level and coastal-discharge changes, relative to recent base-case conditions, were estimated for each of six withdrawal scenarios. Redistributed and additional ground-water withdrawals in the six scenarios were simulated from selected sites in the area between Kualapu`u and `Ualapu`e. For the scenarios tested, model results indicate that withdrawals from existing and proposed wells cause a water-level decline of about 0.1 ft in the vicinity of the Kaunakakai habitat-restoration site. In addition, model results indicate a reduction of ground-water discharge, ranging from 98,000 to 170,000 gal/d, to the model element containing the habitat-restoration site, although the existing spatial discretization in the model is too coarse to reliably estimate the reduction of ground-water discharge to the stream

  16. Numerical Simulation of Ground-Water Withdrawals in the Southern Lihue Basin, Kauai, Hawaii

    USGS Publications Warehouse

    Izuka, Scot K.; Oki, Delwyn S.

    2002-01-01

    Numerical simulations indicate that ground-water withdrawals from the Hanamaulu and Puhi areas of the southern Lihue Basin will result in a decline in water levels and reductions in base flows of streams near proposed new water-supply wells. Most of the changes will be attained within 10 to 20 years of the start of pumping. Except for areas such as Puhi and Kilohana, the freshwater lens in most inland areas of the southern Lihue Basin is thick and model simulations indicate that changes in water level and the position of the freshwater- saltwater interface in response to pumping will be small relative to the present thickness of the freshwater lens. Effects of the proposed withdrawals on streamflow depend on withdrawal rate and proximity of the wells to streams. Placing pumped wells away from streams with low base flow and toward streams with high base flow can reduce the relative effect on individual streams. Simulation of the 0.42-million-gallon-per-day increase in withdrawal projected for 2000 indicates that the resulting changes in water levels and interface position, relative to conditions prior to the withdrawal increase, will be small, and that stream base flow will be reduced by less than 10 percent. Simulation of the 0.83-million-gallon-per-day withdrawal projected for 2010 indicates further thinning of the freshwater lens in the Puhi area, where the lens already may be thin, as well as base-flow reduction in Nawiliwili Stream. Simulation of an alternative distribution of the 0.83-million-gallon-per-day withdrawal indicates that the effects can be reduced by shifting most of the new withdrawal to the Hanamaulu area where the freshwater lens is thicker and stream base flows are greater. Simulation of the 1.16-million-gallon-per-day increase in withdrawal projected for 2020 indicates that if withdrawal is distributed only among Hana-maulu wells 1, 3, and 4, and Puhi well 5A, further thinning of the already-thin freshwater lens in the Puhi area would occur

  17. Assessment of ground-water withdrawals at municipal industrial parks in Puerto Rico, 2000

    USGS Publications Warehouse

    Rodriguez, Jose M.

    2004-01-01

    An assessment of ground-water withdrawals at municipal industrial parks throughout Puerto Rico was conducted to investigate the effect of ground-water usage on nearby surface- and ground-water resources. Water-bearing strata were divided into four generalized hydrogeologic units: (1) fissured aquifers (including karst and non-karst limestone); (2) intergranular aquifers; (3) intergranular aquifers overlying fissured rock units; and (4) strata with local or limited ground-water resources. Approximately 49 percent of the municipal industrial parks are located in areas with local or limited ground-water resources, 29 percent overlie intergranular aquifers, 13 percent overlie fissured aquifers, and 9 percent overlie intergranular units that overlie fissured rock units. Hydrogeologic data for the generalized hydrogeologic units were compiled from published U.S. Geological Survey reports. Depths to ground water near industrial parks range from approximately 20 to 400 feet in the fissured aquifers, 6 to 65 feet in coastal intergranular aquifers, 3 to 30 feet in intergranular aquifers overlying fissured rock units, and 1 to 100 feet in strata with local or limited ground-water resources. Aquifer transmissivities near industrial parks range from approximately 100,000 feet squared per day in the fissured aquifers to less than 100 feet squared per day in the strata with local or limited ground-water resources. Well construction data were compiled from published U.S. Geological Survey reports, drillers? logs, and unpublished reports. Specific capacity for wells near industrial parks ranges from approximately 100 gallons per minute per foot of drawdown in the fissured aquifer at Manati to approximately 0.1 gallon per minute per foot of drawdown in strata with local and limited ground-water resources at Bayamon. Reported well yields near industrial parks ranges from 2,800 gallons per minute in the intergranular aquifer at Santa Isabel to approximately 3 gallons per minute in

  18. Simulation of proposed increases in ground-water withdrawals on the Atlantic City 800-foot sand, New Jersey coastal plain

    USGS Publications Warehouse

    Pope, Daryll A.

    2006-01-01

    The confined Atlantic City 800-foot sand and the unconfined Kirkwood-Cohansey aquifer system (surficial aquifer) are major sources of water for southeastern New Jersey. Because of recent concerns about streamflow depletion resulting from ground-water withdrawals and the potential ecological effects on stream habitat in the area, the focus on future withdrawals has been shifted away from the surficial aquifer to the confined Atlantic City 800-foot sand until the effects of increased withdrawals from the surficial aquifer can be investigated. A study was conducted to evaluate the effects of seven proposed increases in ground-water withdrawals from the Atlantic City 800-foot sand and the Kirkwood-Cohansey aquifer system on the Atlantic City 800-foot sand. The proposed withdrawals are increases above the 2004 allocated rates (full allocation). The effects of full-allocation ground-water withdrawals and the cumulative effect of withdrawals for each of seven proposed increases in withdrawals were simulated using three previously published ground-water flow models: the New Jersey Coastal Plain Regional Aquifer System Analysis model, the Coastal Plain Optimization model, and a model of the Atlantic City 800-foot sand in Atlantic County, New Jersey. These models were used to simulate changes in water levels, the source supplying the increased ground-water flow, and the effects on saltwater movement towards production wells in Cape May County as a result of the proposed increased withdrawals at proposed or existing wells. The results of the simulations represent the effects of the proposed increase from full-allocation withdrawals to an additional 1,825 Mgal/yr (million gallons per year) from the Atlantic City 800-foot sand and an additional 1,045 Mgal/yr from the deep part of the Kirkwood-Cohansey aquifer system near the updip limit of the Atlantic City 800-foot sand. Most of the simulated decline in water levels in Atlantic County occurred as the result of the proposed

  19. Effects of ground-water withdrawals on the Rock River and associated valley aquifer, eastern Rock County, Minnesota

    USGS Publications Warehouse

    Lindgren, Richard J.; Landon, M.K.

    2000-01-01

    Model results indicate that the additional water withdrawn by wells due to anticipated increased ground-water withdrawals was derived from a decrease in net leakage of ground water from the aquifer to the streams. The simulations indicated that the increased ground-water withdrawals and normal precipitation resulted in an increase in induced infiltration from the Rock River of 0.1 cubic feet per second for the Luverne Municipal well field and 0.3 cubic feet per second for the Rock County Rural Water well field. Maximum drawdowns ranged from 0.5 to 1.4 feet near the three well fields. For drought conditions, the simulated streamflow losses constituted approximately 30 percent and nearly 65 percent of the flows in the Rock River for the Luverne Municipal and Rock County Rural Water well fields, respectively. Maximum drawdowns ranged from 3.8 to 7.0 feet near the three well fields. Transient simulations with anticipated increased ground-water withdrawals and drought conditions indicated declines in hydraulic heads ranging from 0.2 to 0.4 feet per year in the vicinity of the three well fields, except for near the Rock River. 

  20. Effects of Withdrawals on Ground-Water Levels in Southern Maryland and the Adjacent Eastern Shore, 1980-2005

    USGS Publications Warehouse

    Soeder, Daniel J.; Raffensperger, Jeff P.; Nardi, Mark R.

    2007-01-01

    Ground water is the primary source of water supply in most areas of Maryland?s Atlantic Coastal Plain, including Southern Maryland. The counties in this area are experiencing some of the most rapid growth and development in the State, resulting in an increased demand for ground-water production. The cooperative, basic water-data program of the U.S. Geological Survey and the Maryland Geological Survey has collected long-term observations of ground-water levels in Southern Maryland and parts of the Eastern Shore for many decades. Additional water-level observations were made by both agencies beginning in the 1970s, under the Power Plant Research Program of the Maryland Department of Natural Resources. These long-term water levels commonly show significant declines over several decades, which are attributed to ground-water withdrawals. Ground-water-level trends since 1980 in major Coastal Plain aquifers such as the Piney Point-Nanjemoy, Aquia, Magothy, upper Patapsco, lower Patapsco, and Patuxent were compared to water use and withdrawal data. Potentiometric surface maps show that most of the declines in ground-water levels can be directly related to effects from major pumping centers. There is also evidence that deep drawdowns in some pumped aquifers may be causing declines in adjacent, unpumped aquifers. Water-level hydrographs of many wells in Southern Maryland show linear declines in levels year after year, instead of the gradual leveling-off that would be expected as the aquifers equilibrate with pumping. A continual increase in the volumes of water being withdrawn from the aquifers is one explanation for why they are not reaching equilibrium. Although reported ground-water production in Southern Maryland has increased somewhat over the past several decades, the reported increases are often not large enough to account for the observed water-level declines. Numerical modeling simulations indicate that a steady, annual increase in the number of small wells could

  1. Optimization of ground-water withdrawal in the lower Fox River communities, Wisconsin

    USGS Publications Warehouse

    Walker, J.F.; Saad, D.A.; Krohelski, J.T.

    1998-01-01

    Pumping from closely spaced wells in the Central Brown County area and the Fox Cities area near the north shore of Lake Winnebago has resulted in the formation of deep cones of depression in the vicinity of the two pumping centers. Water-level measurements indicate there has been a steady decline in water levels in the vicinity of these two pumping centers for the past 50 years. This report describes the use of ground-water optimization modeling to efficiently allocate the ground-water resources in the Lower Fox River Valley. A 3-dimensional ground-water flow model was used along with optimization techniques to determine the optimal withdrawal rates for a variety of management alternatives. The simulations were conducted separately for the Central Brown County area and the Fox Cities area. For all simulations, the objective of the optimization was to maximize total ground-water withdrawals. The results indicate that ground water can supply nearly all of the projected 2030 demand for Central Brown County municipalities if all of the wells are managed (including the city of Green Bay), 8 new wells are installed, and the water-levels are allowed to decline to 100 ft below the bottom of the confining unit. Ground water can supply nearly all of the projected 2030 demand for the Fox Cities if the municipalities in Central Brown County convert to surface water; if Central Brown County municipalities follow the optimized strategy described above, there will be a considerable shortfall of available ground water for the Fox Cities communities. Relaxing the water-level constraint in a few wells, however, would likely result in increased availability of water. In all cases examined, optimization alternatives result in a rebound of the steady-state water levels due to projected 2030 withdrawal rates to levels at or near the bottom of the confining unit, resulting in increased well capacity. Because the simulations are steady-state, if all of the conditions of the model remain

  2. Hydrogeology and Simulated Effects of Ground-Water Withdrawals in the Big River Area, Rhode Island

    USGS Publications Warehouse

    Granato, Gregory E.; Barlow, Paul M.; Dickerman, David C.

    2003-01-01

    The Rhode Island Water Resources Board is considering expanded use of ground-water resources from the Big River area because increasing water demands in Rhode Island may exceed the capacity of current sources. This report describes the hydrology of the area and numerical simulation models that were used to examine effects of ground-water withdrawals during 1964?98 and to describe potential effects of different withdrawal scenarios in the area. The Big River study area covers 35.7 square miles (mi2) and includes three primary surface-water drainage basins?the Mishnock River Basin above Route 3, the Big River Basin, and the Carr River Basin, which is a tributary to the Big River. The principal aquifer (referred to as the surficial aquifer) in the study area, which is defined as the area of stratified deposits with a saturated thickness estimated to be 10 feet or greater, covers an area of 10.9 mi2. On average, an estimated 75 cubic feet per second (ft3/s) of water flows through the study area and about 70 ft3/s flows out of the area as streamflow in either the Big River (about 63 ft3/s) or the Mishnock River (about 7 ft3/s). Numerical simulation models are used to describe the hydrology of the area under simulated predevelopment conditions, conditions during 1964?98, and conditions that might occur in 14 hypothetical ground-water withdrawal scenarios with total ground-water withdrawal rates in the area that range from 2 to 11 million gallons per day. Streamflow depletion caused by these hypothetical ground-water withdrawals is calculated by comparison with simulated flows for the predevelopment conditions, which are identical to simulated conditions during the 1964?98 period but without withdrawals at public-supply wells and wastewater recharge. Interpretation of numerical simulation results indicates that the three basins in the study area are in fact a single ground-water resource. For example, the Carr River Basin above Capwell Mill Pond is naturally losing water

  3. Ground-Water Resources in Kaloko-Honokohau National Historical Park, Island of Hawaii, and Numerical Simulation of the Effects of Ground-Water Withdrawals

    USGS Publications Warehouse

    Oki, Delwyn S.; Tribble, Gordon W.; Souza, William R.; Bolke, Edward L.

    1999-01-01

    Within the Kaloko-Honokohau National Historical Park, which was established in 1978, the ground-water flow system is composed of brackish water overlying saltwater. Ground-water levels measured in the Park range from about 1 to 2 feet above mean sea level, and fluctuate daily by about 0.5 to 1.5 feet in response to ocean tides. The brackish water is formed by mixing of seaward flowing fresh ground water with underlying saltwater from the ocean. The major source of fresh ground water is from subsurface flow originating from inland areas to the east of the Park. Ground-water recharge from the direct infiltration of precipitation within the Park area, which has land-surface altitudes less than 100 feet, is small because of low rainfall and high rates of evaporation. Brackish water flowing through the Park ultimately discharges to the fishponds in the Park or to the ocean. The ground water, fishponds, and anchialine ponds in the Park are hydrologically connected; thus, the water levels in the ponds mark the local position of the water table. Within the Park, ground water near the water table is brackish; measured chloride concentrations of water samples from three exploratory wells in the Park range from 2,610 to 5,910 milligrams per liter. Chromium and copper were detected in water samples from the three wells in the Park and one well upgradient of the Park at concentrations of 1 to 5 micrograms per liter. One semi-volatile organic compound, phenol, was detected in water samples from the three wells in the Park at concentrations between 4 and 10 micrograms per liter. A regional, two-dimensional (areal), freshwater-saltwater, sharp-interface ground-water flow model was used to simulate the effects of regional withdrawals on ground-water flow within the Park. For average 1978 withdrawal rates, the estimated rate of fresh ground-water discharge to the ocean within the Park is about 6.48 million gallons per day, or about 3 million gallons per day per mile of coastline

  4. Simulating the effects of ground-water withdrawals on streamflow in a precipitation-runoff model

    USGS Publications Warehouse

    Zarriello, P.J.; Barlow, P.M.; Duda, P.B.

    2004-01-01

    Precipitation-runoff models are used to assess the effects of water use and management alternatives on streamflow. Often, ground-water withdrawals are a major water-use component that affect streamflow, but the ability of surface-water models to simulate ground-water withdrawals is limited. As part of a Hydrologic Simulation Program-FORTRAN (HSPF) precipitation-runoff model developed to analyze the effect of ground-water and surface-water withdrawals on streamflow in the Ipswich River in northeastern Massachusetts, an analytical technique (STRMDEPL) was developed for calculating the effects of pumped wells on streamflow. STRMDEPL is a FORTRAN program based on two analytical solutions that solve equations for ground-water flow to a well completed in a semi-infinite, homogeneous, and isotropic aquifer in direct hydraulic connection to a fully penetrating stream. One analytical method calculates unimpeded flow at the stream-aquifer boundary and the other method calculates the resistance to flow caused by semipervious streambed and streambank material. The principle of superposition is used with these analytical equations to calculate time-varying streamflow depletions due to daily pumping. The HSPF model can readily incorporate streamflow depletions caused by a well or surface-water withdrawal, or by multiple wells or surface-water withdrawals, or both, as a combined time-varying outflow demand from affected channel reaches. These demands are stored as a time series in the Watershed Data Management (WDM) file. This time-series data is read into the model as an external source used to specify flow from the first outflow gate in the reach where these withdrawals are located. Although the STRMDEPL program can be run independently of the HSPF model, an extension was developed to run this program within GenScn, a scenario generator and graphical user interface developed for use with the HSPF model. This extension requires that actual pumping rates for each well be stored

  5. Estimated Ground-water Withdrawals From the Death Valley Regional Flow System, Nevada and California, 1913-98

    SciTech Connect

    M.T. Moreo; K.J. Halford; R.J. LaCamera; and R.J. Laczniak

    2003-09-30

    Ground-water withdrawals from 1913 through 1998 from the Death Valley regional flow system have been compiled to support a regional,three-dimensional, transient ground-water flow model. Withdrawal locations and depths of production intervals were estimated and associated errors were reported for 9,300 wells. Withdrawals were grouped into three categories: mining, public-supply, and commercial water use; domestic water use; and irrigation water use. In this report, groupings were based on the method used to estimate pumpage. Cumulative ground-water withdrawals from 1913 through 1998 totaled 3 million acre-feet, most of which was used to irrigate alfalfa. Annual withdrawal for irrigation ranged from 80 to almost 100 percent of the total pumpage. About 75,000 acre-feet was withdrawn for irrigation in 1998. Annual irrigation withdrawals generally were estimated as the product of irrigated acreage and application rate. About 320 fields totaling 11,000 acres were identified in six hydrographic areas. Annual application rates for high water-use crops ranged from 5 feet in Penoyer Valley to 9 feet in Pahrump Valley. The uncertainty in the estimates of ground-water withdrawals was attributed primarily to the uncertainty of application rate estimates. Annual ground-water withdrawal was estimated at about 90,000 acre-feet in 1998 with an assigned uncertainty bounded by 60,000 to 130,000 acre-feet.

  6. Estimated Ground-Water Withdrawals from the Death Valley Regional Flow System, Nevada and California, 1913-98

    USGS Publications Warehouse

    Moreo, Michael T.; Halford, Keith J.; La Camera, Richard J.; Laczniak, Randell J.

    2003-01-01

    Ground-water withdrawals from 1913 through 1998 from the Death Valley regional flow system have been compiled to support a regional, three-dimensional, transient ground-water flow model. Withdrawal locations and depths of production intervals were estimated and associated errors were reported for 9,300 wells. Withdrawals were grouped into three categories: mining, public-supply, and commercial water use; domestic water use; and irrigation water use. In this report, groupings were based on the method used to estimate pumpage. Cumulative ground-water withdrawals from 1913 through 1998 totaled 3 million acre-feet, most of which was used to irrigate alfalfa. Annual withdrawal for irrigation ranged from 80 to almost 100 percent of the total pumpage. About 75,000 acre-feet was withdrawn for irrigation in 1998. Annual irrigation withdrawals generally were estimated as the product of irrigated acreage and application rate. About 320 fields totaling 11,000 acres were identified in six hydrographic areas. Annual application rates for high water-use crops ranged from 5 feet in Penoyer Valley to 9 feet in Pahrump Valley. The uncertainty in the estimates of ground-water withdrawals was attributed primarily to the uncertainty of application rate estimates. Annual ground-water withdrawal was estimated at about 90,000 acre-feet in 1998 with an assigned uncertainty bounded by 60,000 to 130,000 acre-feet.

  7. Effects of municipal ground-water withdrawals on the Arbuckle-Simpson Aquifer, Pontotoc County, Oklahoma

    USGS Publications Warehouse

    Savoca, M.E.; Bergman, D.L.

    1994-01-01

    The Arbuckle-Simpson aquifer in south-central Oklahoma consists of a thick sequence of folded and faulted carbonate and clastic rocks of Upper Cambrian to Middle Ordovician age. Fractures and karst features locally increase the aquifer's capacity to transmit and store ground water. The aquifer is a principal source of water for municipal and rural users. A hydrologic study was conducted to evaluate the effects of municipal ground-water withdrawal from the Arbuckle-Simpson aquifer on local ground-water levels and discharge from nearby springs and streams in south-central Pontotoc County. A municipal well was pumped for 63 hours at an average rate of 1,170 gallons per minute. A maximum observed drawdown of 0.3 feet was recorded half a mile from the pumping well. Drawdown was observed as far as 1.2 miles from the pumping well. No measurable response was observed at any of the surface-water-discharge measurement sites; however, recharge from precipitation may have masked any decreases in discharge caused by the pumping. Simultaneous pumping of two municipal wells for 241 hours at average rates of 1,170 and 2,730 gallons per minute resulted in a maximum observed drawdown of 1.3 feet recorded at an average distance of 0.80 miles from the pumping wells. The most distant drawdown observed was at an average distance 1.1 miles from the pumped wells. Less that 2 days after pumping stopped, increases in springflow were recorded at two springs; it is unknown whether these discharge responses reflect the effects of recharge from precipitation, or the combined effects of precipitation and the cessation of ground-water withdrawal. The effects of the stress tests on the hydrologic system were offset by recharge from concurrent precipitation. The maximum observed drawdown represents about 6 percent of the median natural water-level fluctuation during the study period. The effect of drawdown could become critical during extended periods of low precipitation, if water levels are

  8. Ground-water hydrology and projected effects of ground-water withdrawals in the Sevier Desert, Utah

    USGS Publications Warehouse

    Holmes, Walter F.

    1984-01-01

    The principal ground-water reservoir in the Sevier Desert is the unconsolidated basin fill. The fill has been divided generally into aquifers and confining beds, although there are no clearcut boundaries between these units--the primary aquifers are the shallow and deep artesian aquifers. Recharge to the ground-water reservoir is by infiltration of precipitation; seepage from streams, canals, reservoirs, and unconsumed irrigation water; and subsurface inflow from consolidated rocks in mountain areas and from adjoining areas. Discharge is by wells, springs, seepage to the Sevier River, evapotranspiration, and subsurface outflow to adjoining areas.

  9. Hydrogeology and analysis of ground-water withdrawal from the Catahoula aquifer system in the Natchez area, Adams County, Mississippi

    USGS Publications Warehouse

    Strom, E.W.; Burt, D.E.; Oakley, W.T.

    1995-01-01

    The city of Natchez, located in Adams County, Mississippi, relies on ground water for public supply and industrial needs. Most public supply and industrial wells are developed in Catahoula Formation sands of Miocene age. In 1991, an investigation began to describe the hydrogeology, analyze the effects of ground-water withdrawal from currently pumped wells, and project the possible effects of increased ground-water withdrawals on water levels in the Catahoula aquifer system within the Natchez area. The study area covers about 80 square miles in Adams County, southwestern Mississippi. The study area contains several aquifers; however, the most important aquifers in terms of water supply are the Mississippi River alluvial aquifer and the Catahoula aquifer system. In the Natchez area, the Catahoula aquifer system consists of three main sand intervals that form the upper, middle, and lower Catahoula aquifers. Ground-water withdrawal from the Catahoula aquifer system in the study area currently (March 1995) is from 24 wells screened in the three aquifers. The current daily rate of withdrawal is about 9.2 million gallons of water per day. Analysis of the effect of ground-water withdrawal from these wells was made using the Theis nonequilibrium equation and applying the principle of superposition. The calculated drawdown surfaces under current conditions indicate cones of depression surrounding the principal wells. In the upper Catahoula sand, most of the drawdown is concentrated about 1 mile east of the downtown Natchez area, where a maximum drawdown of 95x11 feet was calculated. Most of the drawdown in the middle Catahoula sand occurred in the same general vicinity as in the upper sand, with a maximum calculated drawdown of about 113 feet. Drawdown in the lower Catahoula sand was concentrated about 4x11 miles northeast of downtown Natchez, with a maximum calculated drawdown of about 31 feet. Drawdown-surface maps were made using calculations based on current pumping

  10. Potential hydrologic impacts of ground-water withdrawal from the Cape Cod National Seashore, Truro, Massachusetts

    USGS Publications Warehouse

    LeBlanc, Denis R.

    1982-01-01

    The hydrologic impacts of continuous ground-water withdrawals at 0.75, 1.0, and 1.24 Mgal/d (million gallons per day) from a test-well site in the Cape Cod National Seashore, Truro, Massachusetts, were evaluated with a three-dimensional finite-difference steady-state-flow digital model. The digital model was prepared during an earlier study and is only briefly described. Continuous withdrawal of more than 1.0 Mgal/d from a well screened from 10 to 40 feet below sea level at the test site will result in upward movement of the freshwater-saltwater interface, and most likely saltwater will eventually contaminate the well. Pumping from a shallower well will decrease the potential for the movement of saltwater into the well, but the water table may be drawn down to the well screen. It is unlikely that movement of the freshwater-saltwater interface in response to pumping from the test site at the simulated rates will result in saltwater contamination of the shallow domestic supply wells in Truro. For the simulated pumping schemes, the water-table decline below average (1963-76) levels did not exceed 0.6 foot except near the pumping wells. Continuous withdrawal at the average year-round rate and the average summer rate will decrease freshwater discharge to the wetland and ocean along the northeastern boundary of the aquifer. (USGS)

  11. Simulation of Ground-Water Flow and Optimization of Withdrawals from Aquifers at the Naval Air Station Patuxent River, St. Mary's County, Maryland

    USGS Publications Warehouse

    Dieter, Cheryl A.; Fleck, William B.

    2008-01-01

    Potentiometric surfaces in the Piney Point-Nanjemoy, Aquia, and Upper Patapsco aquifers have declined from 1950 through 2000 throughout southern Maryland. In the vicinity of Lexington Park, Maryland, the potentiometric surface in the Aquia aquifer in 2000 was as much as 170 feet below sea level, approximately 150 feet lower than estimated pre-pumping levels before 1940. At the present rate, the water levels will have declined to the regulatory allowable maximum of 80 percent of available drawdown in the Aquia aquifer by about 2050. The effect of the withdrawals from these aquifers by the Naval Air Station Patuxent River and surrounding users on the declining potentiometric surface has raised concern for future availability of ground water. Growth at Naval Air Station Patuxent River may increase withdrawals, resulting in further drawdown. A ground-water-flow model, combined with optimization modeling, was used to develop withdrawal scenarios that minimize the effects (drawdown) of hypothetical future withdrawals. A three-dimensional finite-difference ground-water-flow model was developed to simulate the ground-water-flow system in the Piney Point-Nanjemoy, Aquia, and Upper Patapsco aquifers beneath the Naval Air Station Patuxent River. Transient and steady-state conditions were simulated to give water-resource managers additional tools to manage the ground-water resources. The transient simulation, representing 1900 through 2002, showed that the magnitude of withdrawal has increased over that time, causing ground-water flow to change direction in some areas. The steady-state simulation was linked to an optimization model to determine optimal solutions to hypothetical water-management scenarios. Two optimization scenarios were evaluated. The first scenario was designed to determine the optimal pumping rates for wells screened in the Aquia aquifer within three supply groups to meet a 25-percent increase in withdrawal demands, while minimizing the drawdown at a control

  12. Municipal ground-water development and withdrawals in the central Lower Peninsula of Michigan, 1870-1987

    USGS Publications Warehouse

    Baltusis, M.A.; Quigley, M.F.; Mandle, Richard J.

    1992-01-01

    Municipal water-supply systems in the central Lower Peninsula of Michigan were categorized into four regions on the basis of source of water for 1987. These categories included water systems that obtained water from aquifers in glacial drift, bedrock, or both, as well as those that obtained water from surface-water sources. Data on ground-water development were collected for 182 municipal water-supply systems for the period 1870-1987. Of the 182 systems, 135 used ground water for supply. Wells in glacial-drift aquifers supplied water for 60 municipalities; wells in bedrock aquifers supplied 58 municipalities. Combinations of wells in bedrock and glacial-drift aquifers supplied 17 municipalities. Surface-water sources supplied 45 municipalities; two municipalities used surface water and ground water. Of the 182 municipal systems, withdrawal data were available for only 145. Withdrawal data were collected for the period 1903-1985. Analysis of annual ground-water withdrawal data for the 145 municipal water-supply systems indicates that average annual per capita municipal ground-water withdrawal ranged from 60 gallons per day per person in 1915 to 166 gallons per day per person in 1973. The maximum reported groundwater withdrawal for the area was 103 million gallons per day in 1979. Records from most municipalities include long periods for which no ground-water withdrawal data are available. The average annual per capita data among the municipalities varies over the period of record because of incomplete reporting of pumping rates, unusually high pumping rates, short-term economic changes, and other changes not associated with local population changes.

  13. Potential hydrologic effects of ground-water withdrawals from the Dakota Aquifer, southwestern Kansas

    USGS Publications Warehouse

    Watts, K.R.

    1985-01-01

    A study was conducted to evaluate the effects of potential development of the Dakota aquifer on the layered aquifer system above Permian rocks in a 5,000 sq mi area of southwestern Kansas. Transmissivity of the Dakota aquifer, determined from analyses of pumping tests, ranges from 100 to 7,100 sq ft/day. Water in the Dakota aquifer is a calcium bicarbonate type water, similar to water in the High Plains aquifer, in the subcrop area. However, in areas distant from the subcrop, water in the Dakota aquifer is a sodium bicarbonate type water with dissolved solids concentrations in excess of 500 mg/L. Gradual declines in the potentiometric surface of the Dakota aquifer have occurred since the onset of pumpage in the 1960's; however, water levels in some wells have risen during the late 1970's. A digital computer model of 3-D groundwater flow was developed to simulate hydrologic conditions of a five-layer hydrologic system for 1975-82 conditions. The major components of the simulated 1975-82 water budget were well discharge from the High Plains aquifer and loss of ground water from storage in the High Plains aquifer. Although downward leakage from the High Plains aquifer in the study area represented only 18,000 acre-ft of the 1,365 ,000 acre-ft discharged from the High Plains aquifer during 1982 , it was a major source of inflow to the Dakota aquifer. Changes in storage in the Dakota aquifer in the study area during 1982 were about 5,000 acre-ft. A base-line projection was made using 1982 simulated hydraulic heads from the calibrated model and 1982 rates of pumpage from both the High Plains and the Dakota aquifers for comparison with eight additional projection simulations in which maximum pumpage from the Dakota aquifer at the end of the projections ranged from about 78,000 to 294,000 acre-ft/yr. The results from the projections indicate that: (1) pumpage from the Dakota aquifer will have a limited effect on hydraulic heads in the High Plains aquifer, (2) drawdown in

  14. Hydrogeology and analysis of ground-water withdrawal in the Mendenhall-D'Lo area, Simpson County, Mississippi

    USGS Publications Warehouse

    Strom, E.W.; Oakley, W.T.

    1995-01-01

    The cities of Mendenhall and D'Lo, located in Simpson County, rely on ground water for their public supply and industrial needs. Most of the ground water comes from an aquifer of Miocene age. A study began in 1991 to describe the hydrogeology, analyze effects of ground-water withdrawal by making a drawdown map, and estimate the effects increased ground-water withdrawal might have on water levels in the Miocene age aquifer in the Mendenhall-D'Lo area. The most significant withdrawals of ground water in the study area are from 10 wells screened in the lower sand of the Catahoula Formation of Miocene age. Analysis of the effect of withdrawals from the 10 wells was made using the Theis non- equilibrium equation and applying the principle of superposition. Analysis of 1994 conditions was based on the pumpage history and aquifer properties deter- mined for each well. The drawdown surface resulting from the analysis indicates three general cones of depression. One cone is in the northwestern D'Lo area, one in the south-central Mendenhall area, and one about 1-1/2 miles east of Mendenhall. Calculated drawdown ranges from 21 to 47 feet. Potential drawdown-surface maps were made for 10 years and 20 years beyond 1994 using a constant pumpage. The map made for 10 years beyond 1994 indicates an average total increase in drawdown of about 5.3 feet. The map made for 20 years beyond 1994 indicates an average total increase in drawdown of about 7.3 feet.

  15. Deformation-induced changes in hydraulic head during ground-water withdrawal

    USGS Publications Warehouse

    Hsieh, Paul A.

    1996-01-01

    Ground-water withdrawal from a confined or semiconfined aquifer causes three-dimensional deformation in the pumped aquifer and in adjacent layers (overlying and underlying aquifers and aquitards). In response to the deformation, hydraulic head in the adjacent layers could rise or fall almost immediately after the start of pumping. This deformation-induced effect suggest that an adjacent layer undergoes horizontal compression and vertical extension when pumping begins. Hydraulic head initially drops in a region near the well and close to the pumped aquifer, but rises outside this region. Magnitude of head change varies from a few centimeters to more than 10 centimeters. Factors that influence the development of deformation-induced effects includes matrix rigidity (shear modulus), the arrangement of aquifer and aquitards, their thicknesses, and proximity to land surface. Induced rise in hydraulic head is prominent in an aquitard that extends from land surface to a shallow pumped aquifer. Induced drop in hydraulic head is likely observed close to the well in an aquifer that is separated from the pumped aquifer by a relatively thin aquitard. Induced effects might last for hours in an aquifer, but could persist for many days in an aquitard. Induced effects are eventually dissipated by fluid flow from regions of higher head to regions of lower head, and by propagation of drawdown from the pumped aquifer into adjacent layers.

  16. Summary of surface-water quality, ground-water quality, and water withdrawals for the Spirit Lake Reservation, North Dakota

    USGS Publications Warehouse

    Vining, Kevin C.; Cates, Steven W.

    2006-01-01

    Available surface-water quality, ground-water quality, and water-withdrawal data for the Spirit Lake Reservation were summarized. The data were collected intermittently from 1948 through 2004 and were compiled from U.S. Geological Survey databases, North Dakota State Water Commission databases, and Spirit Lake Nation tribal agencies. Although the quality of surface water on the reservation generally is satisfactory, no surface-water sources are used for consumable water supplies. Ground water on the reservation is of sufficient quality for most uses. The Tokio and Warwick aquifers have better overall water quality than the Spiritwood aquifer. Water from the Spiritwood aquifer is used mostly for irrigation. The Warwick aquifer provides most of the consumable water for the reservation and for the city of Devils Lake. Annual water withdrawals from the Warwick aquifer by the Spirit Lake Nation ranged from 71 million gallons to 122 million gallons during 2000-04.

  17. Ground-water conditions in Salt Lake Valley, Utah, 1969-83, and predicted effects of increased withdrawals from wells

    USGS Publications Warehouse

    Waddell, K.M.; Seiler, R.L.; Santini, Melissa; Solomon, D.K.

    1987-01-01

    This report was prepared in cooperation with several organizations in the Salt Lake Valley and with the Central Utah Water Conservancy District to present results of a study to determine changes in the ground-water conditions in Salt Lake Valley, Utah, from 1969 to 1983, and to predict the aquifer response to projected withdrawals. The average annual recharge and discharge from the ground-water reservoir in Salt Lake Valley, Utah, during 1969-82 were estimated to be about 352,000 and 353,000 acre-feet per year. Withdrawals from wells increased from 107,000 acre-feet per year during 1964-68 to 117,000 acre-feet per year during 1969-82. The greatest increase in use was for public supply and institutions which increased from 35,000 acre-feet per year during 1964-68 to 46,700 acre-feet per year during 1969-82.

  18. Recovery of Ground-Water Levels from 1988 to 2003 and Analysis of Effects of 2003 and Full-Allocation Withdrawals in Critical Area 2, Southern New Jersey

    USGS Publications Warehouse

    Spitz, Frederick J.; dePaul, Vincent T.

    2008-01-01

    Water levels in the Potomac-Raritan-Magothy aquifer system within Water Supply Critical Area 2 in the southern New Jersey Coastal Plain have recovered as a result of reductions in ground-water withdrawals initiated in the early 1990s. The Critical Area consists of the depleted zone and the threatened margin. The Potomac-Raritan-Magothy aquifer system consists of the Upper, Middle, and Lower aquifers. Generally, ground-water withdrawals from these aquifers declined 5 to 10 Mgal/d (million gallons per day) and water levels recovered 0 to 40 ft (foot) from 1988 to 2003. In order to reevaluate water-allocation restrictions in Critical Area 2 in response to changes in the ground-water-flow system and demands for additional water supply due to increased development, the New Jersey Department of Environmental Protection (NJDEP) needs information about the effects of changes in those allocations. Therefore, the U.S. Geological Survey (USGS), in cooperation with the NJDEP, used an existing ground-water-flow model of the New Jersey Coastal Plain to evaluate the effects of withdrawal alternatives on hydraulic heads in the Potomac-Raritan-Magothy aquifer system in Critical Area 2. The U.S. Geological Survey Regional Aquifer System Analysis model was used to simulate steady-state ground-water flow. Two withdrawal conditions were tested by using the model to evaluate hydraulic heads and differences in heads in these aquifers: 2003 withdrawals and full-allocation withdrawals (17.4 Mgal/d greater than 2003 withdrawals). Model results are presented using head maps and head-difference maps that compare 2003 to full-allocation withdrawals. Mandated hydrologic conditions for Critical Area protection are that the simulated -30-ft head contour not extend beyond the boundary of the depleted zone and (or) be at least 5 mi (miles) updip from the 250-mg/L (milligram per liter) isochlor in all three aquifers. Simulation results indicate that, for 2003 withdrawals, the simulated -30-ft head

  19. Recalibration of a ground-water flow model of the Mississippi River Valley alluvial aquifer in Southeastern Arkansas, 1918, with simulations of hydraulic heads caused by projected ground-water withdrawals through 2049

    USGS Publications Warehouse

    Stanton, Gregory P.; Clark, Brian R.

    2003-01-01

    The Mississippi River Valley alluvial aquifer, encompassing parts of Arkansas, Kentucky, Louisiana, Mississippi, Missouri, and Tennessee supplies an average of 5 billion gallons of water per day. However, withdrawals from the aquifer in recent years have caused considerable drawdown in the hydraulic heads in southeastern Arkansas and other areas. The effects of current ground-water withdrawals and potential future withdrawals on water availability are major concerns of water managers and users as well as the general public. A full understanding of the behavior of the aquifer under various water-use scenarios is critical for the development of viable water-management and alternative source plans. To address these concerns, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, Vicksburg District, and the Arkansas Soil and Water Conservation Commission developed and calibrated a ground-water flow model for the Mississippi River valley alluvial aquifer in southeastern Arkansas to simulate hydraulic heads caused by projected ground-water withdrawals. A previously published ground-water flow model for the alluvial aquifer in southeastern Arkansas was updated and recalibrated to reflect more current pumping stresses with additional stress periods added to bring the model forward from 1982 to 1998. The updated model was developed and calibrated with MODFLOW-2000 finite difference numerical modeling and parameter estimation software. The model was calibrated using hydraulic-head data collected during 1972 and 1982 and hydraulic-head measurements made during spring (February to April) of 1992 and 1998. The residuals for 1992 and 1998 have a mean absolute value of 4.74 and 5.45 feet, respectively, and a root mean square error of 5.9 and 6.72 feet, respectively. The effects of projected ground-water withdrawals were simulated through 2049 in three predictive scenarios by adding five additional stress periods of 10 years each. In the three scenarios

  20. Effects of decreased ground-water withdrawal on ground-water levels and chloride concentrations in Camden County, Georgia, and ground-water levels in Nassau County, Florida, from September 2001 to May 2003

    USGS Publications Warehouse

    Peck, Michael F.; McFadden, Keith W.; Leeth, David C.

    2005-01-01

    During October 2002, the Durango Paper Company formerly Gillman Paper Company) in St. Marys, Georgia, shut down paper-mill operations; the shutdown resulted in decreased ground-water withdrawal in Camden County by 35.6 million gallons per day. The decrease in withdrawal resulted in water-level rise in wells completed in the Floridan aquifer system and the overlying surficial and Brunswick aquifer systems; many wells in the St. Marys area flowed for the first time since the mill began operations during 1941. Pumping at the mill resulted in the development of a cone of depression that coalesced with a larger adjacent cone of depression at Fernandina Beach, Florida. Since closure of the mill, the cone at St. Marys is no longer present, although the cone still exists at Fernandina Beach, Florida. Historical water-level data from the production wells at the mill indicate that the pumping water level ranged from 68 to 235 feet (ft) below North American Vertical Datum of 1988 (NAVD 88) and averaged about 114 ft when the mill was operating. Since the shutdown, it is estimated that water levels at the mill have risen about 140 ft and are now at about 30 ft above NAVD 88. The water-level rise in wells in outlying areas in Camden County was less pronounced and ranged from about 5 to 10 ft above NAVD 88. Because of the regional upward water-level trend in the Upper Floridan aquifer that started during 19992000 in most of the coastal area, combined with a steeper upward trend beginning during October 2002, it was not possible to determine if the 510 ft rise in water levels in wells away from St. Marys was due to the mill closure. In addition to water-level rise of 2226 ft in the Floridan aquifer system, water-level rises in the overlying surficial and Brunswick aquifer systems at St. Marys after the shutdown indicate upward leakage of water. Water levels had stabilized in the confined surficial and Upper and Lower Floridan aquifers by AprilMay 2003; however, the water level in

  1. Simulation of Hydrologic-System Responses to Ground-Water Withdrawals in the Hunt-Annaquatucket-Pettaquamscutt Stream-Aquifer System, Rhode Island

    USGS Publications Warehouse

    Barlow, Paul M.; Ostiguy, Lance J.

    2007-01-01

    A numerical-modeling study was done to better understand hydrologic-system responses to ground-water withdrawals in the Hunt-Annaquatucket-Pettaquamscutt (HAP) stream-aquifer system of Rhode Island. System responses were determined by use of steady-state and transient numerical ground-water-flow models. These models were initially developed in the late 1990s as part of a larger study of the stream-aquifer system. The models were modified to incorporate new data made available since the original study and to meet the objectives of this study. Changes made to the models did not result in substantial changes to simulated ground-water levels, hydrologic budgets, or streamflows compared to those calculated by the original steady-state and transient models. Responses of the hydrologic system are described primarily by changes in simulated streamflows and ground-water levels throughout the basin and by changes to flow conditions in the aquifer in three wetland areas immediately east of the Lafayette State Fish Hatchery, which lies within the Annaquatucket River Basin in the town of North Kingstown. Ground water is withdrawn from the HAP aquifer at 14 large-capacity production wells, at an industrial well, and at 3 wells operated by the Rhode Island Department of Environmental Management at the fish hatchery. A fourth well has been proposed for the hatchery and an additional production well is under development by the town of North Kingstown. The primary streams of interest in the study area are the Hunt, Annaquatucket, and Pettaquamscutt Rivers and Queens Fort Brook. Total model-calculated streamflow depletions in these rivers and brook resulting from withdrawals at the production, industrial, and fish-hatchery wells pumping at average annual 2003 rates are about 4.8 cubic feet per second (ft3/s) for the Hunt River, 3.3 ft3/s for the Annaquatucket River, 0.5 ft3/s for the Pettaquamscutt River, and 0.5 ft3/s for Queens Fort Brook. The actual amount of streamflow reduction

  2. Balancing Ground-Water Withdrawals and Streamflow in the Hunt-Annaquatucket-Pettaquamscutt Basin, Rhode Island

    USGS Publications Warehouse

    Barlow, Paul M.; Dickerman, David C.

    2001-01-01

    Ground water withdrawn for water supply reduces streamflow in the Hunt-Annaquatucket-Pettaquamscutt Basin in Rhode Island. These reductions may adversely affect aquatic habitats. A hydrologic model was prepared by the U.S. Geological Survey in cooperation with the Rhode Island Water Resources Board, Town of North Kingstown, Rhode Island Department of Environmental Management, and Rhode Island Economic Development Corporation to aid water-resource planning in the basin. Results of the model provide information that helps water suppliers and natural-resource managers evaluate strategies for balancing ground-water development and streamflow reductions in the basin.

  3. Optimization of ground-water withdrawal at the old O-Field area, Aberdeen Proving Ground, Maryland

    USGS Publications Warehouse

    Banks, William S.L.; Dillow, Jonathan J.A.

    2001-01-01

    The U.S. Army disposed of chemical agents, laboratory materials, and unexploded ordnance at the Old O-Field landfill at Aberdeen Proving Ground, Maryland, beginning prior to World War II and continuing until at least the 1950?s. Soil, ground water, surface water, and wetland sediments in the Old O-Field area were contaminated by the disposal of these materials. The site is in the Atlantic Coastal Plain, and is characterized by a complex series of Pleistocene and Holocene sediments formed in various fluvial, estuarine, and marine-marginal hydrogeologic environments. A previously constructed transient finite-difference ground-water-flow model was used to simulate ground-water flow and the effects of a pump-and-treat remediation system designed to prevent contaminated ground water from flowing into Watson Creek (a tidal estuary and a tributary to the Gunpowder River). The remediation system consists of 14 extraction wells located between the Old O-Field landfill and Watson Creek.Linear programming techniques were applied to the results of the flow-model simulations to identify optimal pumping strategies for the remediation system. The optimal management objective is to minimize total withdrawal from the water-table aquifer, while adhering to the following constraints: (1) ground-water flow from the landfill should be prevented from reaching Watson Creek, (2) no extraction pump should be operated at a rate that exceeds its capacity, and (3) no extraction pump should be operated at a rate below its minimum capacity, the minimum rate at which an Old O-Field pump can function. Water withdrawal is minimized by varying the rate and frequency of pumping at each of the 14 extraction wells over time. This minimizes the costs of both pumping and water treatment, thus providing the least-cost remediation alternative while simultaneously meeting all operating constraints.The optimal strategy identified using this objective and constraint set involved operating 13 of the 14

  4. Hydrogeology and simulated effects of ground-water withdrawals for citrus irrigation, Hardee and De Soto counties, Florida

    USGS Publications Warehouse

    Metz, P.A.

    1995-01-01

    The hydrogeology of Hardee and De Soto Counties in west-central Florida was evaluated, and a ground-water flow model was developed to simulate the effects of expected increases in ground-water withdrawals for citrus irrigation on the potentiometric surfaces of the intermediate aquifer system and the Upper Floridan aquifer. In 1988, total citrus acreage in Hardee and De Soto Counties was 89,041 acres. By the year 2020, citrus acreage is projected to increase to 130,000 acres. Ground water is the major source of water supply in the study area, and 94 percent of the ground-water withdrawn in the area is used for irrigation purposes. The principal sources of ground water in the study area are the surficial aquifer, the intermediate aquifer system, and upper water-yielding units of the Floridan aquifer system, commonly referred to as the Upper Floridan aquifer. The surficial aquifer is a permeable hydrogeo1ogic unit contiguous with land surface that is comprised predominately of surficial quartz sand deposits that generally are less than 100 feet thick. The intermediate aquifer system is a somewhat less permeable hydrogeologic unit that lies between and retards the exchange of water between the overlying surficial aquifer and the underlying Upper Floridan aquifer. Thickness of the intermediate aquifer system ranges from about 200 to 500 feet and transmissivity ranges from 400 to 7,000 feet squared per day. The highly productive Upper Floridan aquifer consists of 1,200 to 1,400 feet of solution-riddled and fractured limestone and dolomite. Transmissivity values for this aquifer range from 71,000 to 850,000 feet squared per day. Wells open to the Upper Floridan aquifer. the major source of water in the area, can yield as much as 2,500 gallons of water per minute. The potential effects of projected increases in water withdrawals for citrus irrigation on groundwater heads were evaluated by the use of a quasi-three-dimensional, finite-difference, ground-water flow model. The

  5. Estimating pumping time and ground-water withdrawals using energy- consumption data

    USGS Publications Warehouse

    Hurr, R.T.; Litke, D.W.

    1989-01-01

    Evaluation of the hydrology of an aquifer requires knowledge about the volume of groundwater in storage and also about the volume of groundwater withdrawals. Totalizer flow meters may be installed at pumping plants to measure withdrawals; however, it generally is impractical to equip all pumping plants in an area with meters. A viable alternative is the use of rate-time methods. Rate-time methods may be used at individual pumping plants to decrease the data collection necessary for determining withdrawals. At sites where pumping-time measurement devices are not installed, pumping time may be determined on the basis of energy consumption and power demand. At pumping plants where energy consumption is metered, data acquired by reading of meters is used to estimate pumping time. Care needs to be taken to read these meters correctly. At pumping plants powered by electricity, the calculations need to be modified if transformers are present. At pumping plants powered by natural gas, the effects of the pressure-correction factor need to be included in the calculations. At pumping plants powered by gasoline, diesel oil, or liquid petroleum gas, the geometry of storage tanks needs to be analyzed as part of the calculations. The relation between power demand and pumping rate at a pumping plant can be described through the use of the power-consumption coefficient. Where equipment and hydrologic conditions are stable, this coefficient can be applied to total energy consumption at a site to estimate total groundwater withdrawals. Random sampling of power consumption coefficients can be used to estimate area-wide groundwater withdrawal. (USGS)

  6. Simulation of the effects of ground-water withdrawals and recharge on ground-water flow in Cape Cod, Martha's Vineyard, and Nantucket Island basins, Massachusetts

    USGS Publications Warehouse

    Masterson, John P.; Barlow, Paul M.

    1994-01-01

    The effects of changing patterns of ground-water pumping and aquifer recharge on the surface-water and ground-water hydrologic systems were determined for the Cape Cod, Martha's Vineyard, and Nantucket Island Basins. Three-dimensional, transient, ground-water-flow modelS that simulate both freshwater and saltwater flow were developed for the f1ow cells of Cape Cod which currently have large-capacity public-supply wells. Only the freshwater-flow system was simulated for the Cape Cod flow cells where public-water supply demands are satisfied by small-capacity domestic wells. Two- dimensional, finite-difference, change models were developed for Martha's Vineyard and Nantucket Island to determine the projected drawdowns in response to projected in-season pumping rates for 180 days of no aquifer recharge. Results of the simulations indicate very little change in the position of the freshwater-saltwater interface from predevelopment flow conditions to projected ground-water pumping and recharge rates for Cape Cod in the year 2020. Results of change model simulations for Martha's Vineyard and Nantucket Island indicate that the greatest impact in response to projected in-season ground-water pumping occurs at the pumping centers and the magnitude of the drawdowns are minimal with respect to the total thickness of the aquifers.

  7. Potential hydrologic effects of ground-water withdrawals from the Dakota Aquifer, southwestern Kansas

    USGS Publications Warehouse

    Watts, Kenneth R.

    1989-01-01

    , similar to water in the High Plains aquifer, in the subcrop area. However, in areas distant from the subcrop, water in the Dakota aquifer is a sodium bicarbonate type water with dissolved-solids concentrations in excess of 500 milligrams per liter. In some parts of the study area, water from the Dakota presents high to very high salinity and sodium hazards to crops and soil when it is used for irrigation. The Cheyenne aquifer locally contains mineralized water, as indicated by the response of resistivity curves on geophysical logs. Hydrographs of wells completed in the Dakota aquifer indicate that the Dakota and High Plains aquifers are hydraulically connected in and near subcrop areas. Locally, the Dakota aquifer has converted from confined to unconfined conditions as a result of declining water levels due to pumpage from the Dakota aquifer and as the result of depletion of the High Plains aquifer in subcrop areas. Gradual declines in the potentiometric surface of the Dakota aquifer have occurred since the onset of pumpage in the 1960's; however, water levels in some wells have risen during the late 1970's. A digital computer model of three-dimensional groundwater flow was developed to simulate hydrologic conditions of a five-layer hydrologic system for 1975-82 conditions. The major components of the simulated 1975-82 water budget were well discharge from the High Plains aquifer and loss of ground water from storage in the High Plains aquifer. Although downward leakage from the High Plains aquifer in the study area represented only 18,000 acre-feet of the 1,365,000 acre-feet discharged from the High Plains aquifer during 1982, it was a major source of inflow to the Dakota aquifer. Changes in storage in the Dakota aquifer in the study area during 1982 were about 5,000 acre-feet. A baseline projection was made using 1982 simulated hydraulic heads from the calibrated model and 1982 rates of pumpage from both the High Plains and the Dakota aquifer

  8. Sinkhole development resulting from ground-water withdrawal in the Tampa area, Florida

    USGS Publications Warehouse

    Sinclair, William C.

    1982-01-01

    The area of municipal well fields on the Gulf Coastal Plain north of tampa, Fla., is densely pitted with natural sinkholes and sinkhole lakes that have resulted from collapse of surficial sand and clay into solution cavities in the underlying carbonate rocks of the Floridan aquifer. Although solution of the underlying rocks is the ultimate cause of sinkholes, some have been induced by abrupt changes in ground-water levels caused by pumping. Declines in water levels cause loss of support to the bedrock roofs over cavities and to surficial material overlying openings in the top of bedrock. The volume of calcium, magnesium , and carbonate (the constituents of limestone and dolomite) in solution in the water withdrawn from four well fields near Tampa totaled about 240,000 cubic feet in 1978. Most induced solution takes place at the limestone surface however, and the area of induced recharge is so extensive that the effect of induced limestone solution on sinkhole development is negligible. Alinement of established sinkholes along joint patterns in the bedrock suggests that a well along these lineations might have direct hydraulic connection with a zone of incipient sinkholes. Therefore, pumping of large-capacity wells along such lineations would increase the probability of sinkhole development. Although sinkholes generally form abruptly in the study area, local changes such as vegetative stress, ponding of rainfall, misalinement of structures, and turbidity in well water are all indications that percollapse subsidence may be taking place. (USGS)

  9. Estimated public-water supply and industrial-commercial ground-water withdrawals and returns in Nassau County, Long Island, New York, 1973-79

    USGS Publications Warehouse

    Snavely, D.S.; Williams, J.F.

    1985-01-01

    Nassau County, New York depends upon ground water for its freshwater supply. The primary water uses are for public-water supply and industrial-commercial purposes, which together accounted for 202 Mgal/d (million gallons per day) in 1975. Public-water suppliers withdrew 85 percent of their water from the Magothy Formation. About 133 Mgal/d was returned to the ground after use in 1975, and about 69; Mgal/d was discharged to tidewater. In addition, about 34 Mgal/d infiltrated into sewerlines in 1975 and was also discharged to tidewater. Because of the importance of this freshwater supply, the New York State Department of Environmental conservation reviews applications for the installation of wells and compiles data on pumpage throughout Long Island. It also reviews applications to discharge wastewater into the surface water and ground water of the State. This report summarizes the data filed with the New York State Department of Environmental Conservation for Nassau County during 1973-79. It presents data and estimates on withdrawals for public and industrial-commercial supply, returns to the ground, and discharges through sewer systems. It also includes information on population and land use. (USGS)

  10. Geohydrology of the French Creek basin and simulated effects of droughtand ground-water withdrawals, Chester County, Pennsylvania

    USGS Publications Warehouse

    Sloto, Ronald A.

    2004-01-01

    recharge rate of 6.2 in/yr. Average conditions were simulated by adjusting the recharge rate until simulated streamflow at streamflow-measurement station 01472157 matched the long-term (1968-2001) average base flow of 54.1 cubic feet per second. The recharge rate used for average conditions was 15.7 in/yr. The effect of drought in the French Creek Basin was simulated using a drought year recharge rate of 8 in/yr for 3 months. After 3 months of drought, the simulated streamflow of French Creek at streamflow-measurement station 01472157 decreased 34 percent. The simulations show that after 6 months of average recharge (15.7 in/yr) following drought, streamflow and water levels recovered almost to pre-drought conditions. The effect of increased ground-water withdrawals on stream base flow in the South Branch French Creek Subbasin was simulated under average and drought conditions with pumping rates equal to 50, 75, and 100 percent of the Delaware River Basin Commission Ground Water Protected Area (GWPA) withdrawal limit (1,393 million gallons per year) with all pumped water removed from the basin. For average recharge conditions, the simulated streamflow of South Branch French Creek at the mouth decreased 18, 28, and 37 percent at a withdrawal rate equal to 50, 75, and 100 percent of the GWPA limit, respectively. After 3 months of drought recharge conditions, the simulated streamflow of South Branch French Creek at the mouth decreased 27, 40, and 52 percent at a withdrawal rate equal to 50, 75, and 100 percent of the GWPA limit, respectively. The effect of well location on base flow, water levels, and the sources of water to the well was simulated by locating a hypothetical well pumping 200 gallons per minute in different places in the Beaver Run Subbasin with all pumped water removed from the basin. The smallest reduction in the base flow of Beaver Run was from a well on the drainage divide

  11. Simulated effects of projected withdrawals from the Wenonah-Mount Laurel Aquifer on ground-water levels in the Camden, New Jersey, area and vicinity

    USGS Publications Warehouse

    Navoy, A.S.

    1994-01-01

    The Wenonah-Mount Laurel aquifer is being considered as a potential source of future water supply for the Camden, New Jersey, area. The deeper Potomac- Raritan-Magothy aquifer system is currently the major major source of water supply for the area, but its use may be curtailed or reduced by 35 percent of 1983 withdrawals through its designation by the New Jersey Department of Environmental Protection and Energy as "Water Supply Critical Area#2." Withdrawals from the Wenonah-Mount Laurel aquifer currently (1989) total about 7 million gallons per day. The anticipated use of this aquifer by communities with access to it, as an alternative supply, could increase to more than 14 million gallons per day by 2020. If the communities of Clayton and Glassboro decrease their withdrawals from the Potomac-Raritan-Magothy aquifer system by 50 percent or cease them entirely because of their proximity to saline water, the use of Wenonah-Mount Laurel aquifer could increase to greater than 15 million gallons per day by 2020. Simulation of the ground-water system indicates that the projected increase in withdrawals will cause cones of depression in the potentiometric surface of the Wenonah-Mount Laurel aquifer in the Camden metro- politan area by 2020 that extend to depths ranging from 10 feet above sea level to 60 feet below sea level. This represents a secline of about 40 to 100 feet thr 1990 conditions. Withdrawals in northeastern Burlington County will cause a large cone of depression that, by 2020, will extend to depths of about 220 feet below sea level, represent- ing a decline of about 140 feet from 1990 conditions. Simulation results indicate that water levels in the Wenonah-Mount Laurel aquifer near the Salem Nuclear Power Plant are somewhat insensitive to withdrawals elsewhere in the aquifer. In some areas, especially in Burlington County, the cones of depression have developed in proximity to the aquifer-outcrop area and could induce infiltration from streams crossing the

  12. Effects of Land-Use Changes and Ground-Water Withdrawals on Stream Base Flow, Pocono Creek Watershed, Monroe County, Pennsylvania

    USGS Publications Warehouse

    Sloto, Ronald A.

    2008-01-01

    The Pocono Creek watershed drains 46.5 square miles in eastern Monroe County, Pa. Between 2000 and 2020, the population of Monroe County is expected to increase by 70 percent, which will result in substantial changes in land-use patterns. An evaluation of the effect of reduced recharge from land-use changes and additional ground-water withdrawals on stream base flow was done by the U.S. Geological Survey (USGS) in cooperation with the U.S. Environmental Protection Agency (USEPA) and the Delaware River Basin Commission as part of the USEPA?s Framework for Sustainable Watershed Management Initiative. Two models were used. A Soil and Water Assessment Tool (SWAT) model developed by the USEPA provided areal recharge values for 2000 land use and projected full buildout land use. The USGS MODFLOW-2000 ground-water-flow model was used to estimate the effect of reduced recharge from changes in land use and additional ground-water withdrawals on stream base flow. This report describes the ground-water-flow-model simulations. The Pocono Creek watershed is underlain by sedimentary rock of Devonian age, which is overlain by a veneer of glacial deposits. All water-supply wells are cased into and derive water from the bedrock. In the ground-water-flow model, the surficial geologic units were grouped into six categories: (1) moraine deposits, (2) stratified drift, (3) lake deposits, (4) outwash, (5) swamp deposits, and (6) undifferentiated deposits. The unconsolidated surficial deposits are not used as a source of water. The ground-water and surface-water systems are well connected in the Pocono Creek watershed. Base flow measured on October 13, 2004, at 27 sites for model calibration showed that streams gained water between all sites measured except in the lower reach of Pocono Creek. The ground-water-flow model included the entire Pocono Creek watershed. Horizontally, the modeled area was divided into a 53 by 155 cell grid with 6,060 active cells. Vertically, the modeled area

  13. Hydrologic evaluation of proposed ground-water withdrawals in Muleshoe Flat near Wheatland, southeastern Wyoming

    USGS Publications Warehouse

    Hoxie, D.T.

    1983-01-01

    The hydrologic effects of proposed irrigation with groundwater of 8,320 acres of land in Muleshoe Flat, a 34 sq mi area in west-central Platte County, Wyoming, were assessed. Results generated by a digital groundwater flow model indicate that, at the end of a 40-yr period, groundwater level declines of more than 50 ft can be expected in an area of 12.5 sq mi and of more than 200 ft in an area of 7 sq mi. In addition, streamflow depletions of 4,300 acre-ft/yr can be expected in the Laramie River and 4,700 acre-ft/yr in Sybille Creek. Additional hydrologic field data collection prior to initiation of the proposed irrigation development would improve these assessments. Applications for the proposed irrigation wells were denied subsequent to the data collection and analysis described in this report. (Author 's abstract)

  14. Withdrawal of ground water and pond water on Long Island from 1904 to 1949

    USGS Publications Warehouse

    Lusczynski, Norbert J.

    1950-01-01

    For more than 50 years the highly productive and readily replenishable water-bearing sands and gravels on Long Island -- capable of yielding an average of at least 1,000 million gallons a day -- and also some surface streams and ponds have been utilized on a large scale of public water supply and industrial, agricultural and domestic uses. During the drought months of 1949, when many surface and groundwater supplied were being depleted at an alarming rate in many localities in the Northeast, the abundant water resources of Long Island provided sufficient water for public water supply for a large number of private companies and municipalities, as well as for large emergency drafts by the City of New York. In addition they kept industrial concerns from curtailing production, saved millions of dollars of potato, cauliflower, and other Long Island crops, and even furnished, during the summer heat, comfort cooling and theatergoers.

  15. Use of Superposition Models to Simulate Possible Depletion of Colorado River Water by Ground-Water Withdrawal

    USGS Publications Warehouse

    Leake, Stanley A.; Greer, William; Watt, Dennis; Weghorst, Paul

    2008-01-01

    According to the 'Law of the River', wells that draw water from the Colorado River by underground pumping need an entitlement for the diversion of water from the Colorado River. Consumptive use can occur through direct diversions of surface water, as well as through withdrawal of water from the river by underground pumping. To develop methods for evaluating the need for entitlements for Colorado River water, an assessment of possible depletion of water in the Colorado River by pumping wells is needed. Possible methods include simple analytical models and complex numerical ground-water flow models. For this study, an intermediate approach was taken that uses numerical superposition models with complex horizontal geometry, simple vertical geometry, and constant aquifer properties. The six areas modeled include larger extents of the previously defined river aquifer from the Lake Mead area to the Yuma area. For the modeled areas, a low estimate of transmissivity and an average estimate of transmissivity were derived from statistical analyses of transmissivity data. Aquifer storage coefficient, or specific yield, was selected on the basis of results of a previous study in the Yuma area. The USGS program MODFLOW-2000 (Harbaugh and others, 2000) was used with uniform 0.25-mile grid spacing along rows and columns. Calculations of depletion of river water by wells were made for a time of 100 years since the onset of pumping. A computer program was set up to run the models repeatedly, each time with a well in a different location. Maps were constructed for at least two transmissivity values for each of the modeled areas. The modeling results, based on the selected transmissivities, indicate that low values of depletion in 100 years occur mainly in parts of side valleys that are more than a few tens of miles from the Colorado River.

  16. Summary appraisals of the Nation's ground-water resources; New England region

    USGS Publications Warehouse

    Sinnott, Allen

    1982-01-01

    Withdrawals of fresh ground water in 1975 aggregated about 220 billion gallons (830 hm3), or about 12 percent of the total freshwater withdrawals (from all sources) of 1,800 billion gallons (6,800 hm3). In view of the available ground-water reserves, considerable additional water, for the anticipated continuing increase in population and economic activity, could be developed.

  17. Characterization of surface-water resources in the Great Basin National Park area and their susceptibility to ground-water withdrawals in adjacent valleys, White Pine County, Nevada

    USGS Publications Warehouse

    Elliott, Peggy E.; Beck, David A.; Prudic, David E.

    2006-01-01

    Eight drainage basins and one spring within the Great Basin National Park area were monitored continually from October 2002 to September 2004 to quantify stream discharge and assess the natural variability in flow. Mean annual discharge for the stream drainages ranged from 0 cubic feet per second at Decathon Canyon to 9.08 cubic feet per second at Baker Creek. Seasonal variability in streamflow generally was uniform throughout the network. Minimum and maximum mean monthly discharges occurred in February and June, respectively, at all but one of the perennial streamflow sites. Synoptic-discharge, specific-conductance, and water- and air-temperature measurements were collected during the spring, summer, and autumn of 2003 along selected reaches of Strawberry, Shingle, Lehman, Baker, and Snake Creeks, and Big Wash to determine areas where surface-water resources would be susceptible to ground-water withdrawals in adjacent valleys. Comparison of streamflow and water-property data to the geology along each stream indicated areas where surface-water resources likely or potentially would be susceptible to ground-water withdrawals. These areas consist of reaches where streams (1) are in contact with permeable rocks or sediments, or (2) receive water from either spring discharge or ground-water inflow.

  18. Effects of Surface-Water Diversion and Ground-Water Withdrawal on Streamflow and Habitat, Punaluu Stream, Oahu, Hawaii

    USGS Publications Warehouse

    Oki, Delwyn S.; Wolff, Reuben H.; Perreault, Jeff A.

    2006-01-01

    The surface- and ground-water resources of the Punaluu area of northeast Oahu, Hawaii, have been and continue to be important for cultural, domestic, agricultural, recreational, and aesthetic purposes. Punaluu Stream flows perennially because rain falls frequently in the area and ground water discharges to the stream. Flow in Punaluu Stream is reduced by the direct diversion of water for off-stream uses and possibly from the withdrawal of ground water near the stream. Punaluu Ditch diverts water from Punaluu Stream near an altitude of 210 feet. During the recent period 1995-2004, discharge in Punaluu Stream that was equaled or exceeded 50 percent of the time (median or Q50 discharge) and discharge that was equaled or exceeded 95 percent of the time (Q95 discharge) measured immediately upstream from the Punaluu Ditch diversion intake, respectively, were 18 and 13 cubic feet per second, whereas the Q50 and Q95 discharges measured immediately downstream from the diversion intake, respectively, were 7.0 and 1.3 cubic feet per second. Thus, near an altitude of 210 feet, diversion of surface water by the Punaluu Ditch caused the Q50 discharge in Punaluu Stream to be reduced to 39 percent of the natural Q50 discharge, and the Q95 discharge was reduced to 10 percent of the natural value. The relative effects of the Punaluu Ditch diversion on flow in Punaluu Stream decreased in a downstream direction, mainly because of the compensating effects of tributary inflows and ditch return flows. At an altitude of 10 feet, the Q50 discharge in Punaluu Stream was 82 percent of the natural Q50 discharge, and the Q95 discharge was 69 percent of the natural value. Changes in streamflow affect the quantity and quality of physical habitat used by native stream fauna. The Physical Habitat Simulation System (PHABSIM) approach was used to evaluate the effects of different diversion scenarios on physical habitat for selected native species in Punaluu Stream. Habitat-suitability criteria

  19. Geohydrology of the Central Oahu, Hawaii, Ground-Water Flow System and Numerical Simulation of the Effects of Additional Pumping

    USGS Publications Warehouse

    Oki, Delwyn S.

    1998-01-01

    A two-dimensional, finite-difference, ground-water flow model was developed for the central Oahu flow system, which is the largest and most productive ground-water flow system on the island. The model is based on the computer code SHARP which simulates both freshwater and saltwater flow. The ground-water model was developed using average pumping and recharge conditions during the 1950's, which was considered to be a steady-state period. For 1950's conditions, model results indicate that 62 percent (90.1 million gallons per day) of the discharge from the Schofield ground-water area flows southward and the remaining 38 percent (55.2 million gallons per day) of the discharge from Schofield flows northward. Although the contribution of recharge from infiltration of rainfall and irrigation water directly on top of the southern and northern Schofield ground-water dams was included in the model, the distribution of natural discharge from the Schofield ground-water area was estimated exclusive of the recharge on top of the dams. The model was used to investigate the long-term effects of pumping under future land-use conditions. Future recharge was conservatively estimated by assuming no recharge associated with agricultural activities. Future pumpage used in the model was based on the 1995-allocated rates. Model results indicate that the long-term effect of pumping at the 1995-allocated rates will be a reduction of water levels from present (1995) conditions in all ground-water areas of the central Oahu flow system. In the Schofield ground-water area, model results indicate that water levels could decline about 30 feet from the 1995 water-level altitude of about 275 feet. In the remaining ground-water areas of the central Oahu flow system, water levels may decline from less than 1 foot to as much as 12 feet relative to 1995 water levels. Model results indicate that the bottoms of several existing deep wells in northern and southern Oahu extend below the model

  20. Hydrogeology, water quality, and simulated effects of ground-water withdrawals from the Floridan aquifer system, Seminole County and vicinity, Florida

    USGS Publications Warehouse

    Spechler, Rick M.; Halford, Keith J.

    2001-01-01

    The hydrogeology and ground-water quality of Seminole County in east-central Florida was evaluated. A ground-water flow model was developed to simulate the effects of both present day (September 1996 through August 1997) and projected 2020 ground-water withdrawals on the water levels in the surficial aquifer system and the potentiometric surface of the Upper and Lower Floridan aquifers in Seminole County and vicinity. The Floridan aquifer system is the major source of ground water in the study area. In 1965, ground-water withdrawals from the Floridan aquifer system in Seminole County were about 11 million gallons per day. In 1995, withdrawals totaled about 69 million gallons per day. Of the total ground water used in 1995, 74 percent was for public supply, 12 percent for domestic self-supplied, 10 percent for agriculture self-supplied, and 4 percent for recreational irrigation. The principal water-bearing units in Seminole County are the surficial aquifer system and the Floridan aquifer system. The two aquifer systems are separated by the intermediate confining unit, which contains beds of lower permeability sediments that confine the water in the Floridan aquifer system. The Floridan aquifer system has two major water-bearing zones (the Upper Floridan aquifer and the Lower Floridan aquifer), which are separated by a less-permeable semiconfining unit. Upper Floridan aquifer water levels and spring flows have been affected by ground-water development. Long-term hydrographs of four wells tapping the Upper Floridan aquifer show a general downward trend from the early 1950's until 1990. The declines in water levels are caused predominantly by increased pumpage and below average annual rainfall. From 1991 to 1998, water levels rose slightly, a trend that can be explained by an increase in average annual rainfall. Long-term declines in the potentiometric surface varied throughout the area, ranging from about 3 to 12 feet. Decreases in spring discharge also have been

  1. Evaluation of ground-water flow and land-surface subsidence caused by hypothetical withdrawals in the northern part of the Gulf Coast Aquifer system, Texas

    USGS Publications Warehouse

    Kasmarek, Mark C.; Reece, Brian D.; Houston, Natalie A.

    2005-01-01

    During 2003?04 the U.S. Geological Survey, in cooperation with the Texas Water Development Board (TWDB) and the Harris-Galveston Coastal Subsidence District (HGCSD), used the previously developed Northern Gulf Coast Ground-Water Availability Modeling (NGC GAM) model to evaluate the effects of hypothetical projected withdrawals on ground-water flow in the northern part of the Gulf Coast aquifer system and land-surface subsidence in the NGC GAM model area of Texas. The Gulf Coast aquifer system comprises, from the surface, the Chicot and Evangeline aquifers, the Burkeville confining unit, the Jasper aquifer, and the Catahoula confining unit. Two withdrawal scenarios were simulated. The first scenario comprises historical withdrawals from the aquifer system for 1891?2000 and hypothetical projected withdrawals for 2001?50 compiled by the TWDB (TWDB scenario). The projected withdrawals compiled by the TWDB are based on ground-water demands estimated by regional water planning groups. The second scenario is a ?merge? of the TWDB scenario with an alternate set of projected withdrawals from the Chicot and Evangeline aquifers in the Houston metropolitan area for 1995?2030 provided by the HGCSD (HGCSD scenario). Under the TWDB scenario withdrawals from the entire system are projected to be about the same in 2050 as in 2000. The simulated potentiometric surfaces of the Chicot aquifer for 2010, 2020, 2030, 2040, and 2050 show relatively little change in configuration from the simulated 2000 potentiometric surface (maximum water-level depths in southern Harris County 150?200 feet below NGVD 29). The simulated decadal potentiometric surfaces of the Evangeline aquifer show the most change between 2000 and 2010. The area of water levels 250?400 feet below NGVD 29 in western Harris County in 2000 shifts southeastward to southern Harris County, and water levels recover to 200?250 feet below NGVD 29 by 2010. Water levels in southern Harris County recover to 150?200 feet below NGVD 29

  2. Simulation of five ground-water withdrawal projections for the Black Mesa area, Navajo and Hopi Indian Reservations, Arizona

    USGS Publications Warehouse

    Brown, J.G.; Eychaner, J.H.

    1988-01-01

    The N Aquifer is the main source of water in the 5,400 sq mi Black Mesa area in the Navajo and Hopi Indian Reservations in northeastern Arizona. Water in the aquifer is under confined conditions in the central 3,300 sq mi of the area. Maximum saturated thickness is about 1,050 ft. Annual groundwater withdrawals from 1972 through 1986 averaged 5,480 acre-ft and included 3,820 acre-ft used to operate a coal mine on Black Mesa. As a result, water levels have declined in a large part of the aquifer. The coal company has applied for a permanent permit under the Surface Mining Control and Reclamation Act of 1977. An existing mathematical model of the aquifer in the Black Mesa area was converted to a newer model program and recalibrated by using revised estimates of selected aquifer parameters and a finer spatial grid. The model was used to simulate four groundwater withdrawal alternatives that combined the existing and proposed mining plans with projected constant or increasing pumpage for nearby communities. A fifth alternative combined increasing community pumpage with no mine withdrawals and was used as a basis for comparison. Simulated water levels for the year 2031 in the coal-lease area are projected to be 60 ft lower than in 1985 for the proposed mining plan combined with growing community pumpage and > 100 ft lower than predevelopment water levels over an area of 1,660 sq mi. Groundwater would rise to within 100 ft of predevelopment levels < 10 yr after mine withdrawals cease. Withdrawals at the mine were a minor factor in determining simulated water levels at most communities in the study area. Water levels at Tuba City were not affected by mine pumpage in any projection. (Author 's abstract)

  3. Effects of ground-water withdrawals on flow in the Sauk River Valley Aquifer and on streamflow in the Cold Spring area, Minnesota

    USGS Publications Warehouse

    Lindgren, R.J.

    2001-01-01

    The simulated contributing areas for selected watersupply wells in the Cold Spring area generally extend to and possibly beyond the model boundaries to the north and to the southeast. The contributing areas for the Gold'n Plump Poultry Processing Plant supply wells extend: (1) to the Sauk River, (2) to the north to and possibly beyond to the northern model boundary, and (3) to the southeast to and possibly beyond the southeastern model boundary. The primary effects of projected increased ground-water withdrawals of 0.23 cubic feet per second (7.5 percent increase) were to: (1) decrease outflow from the Sauk River Valley aquifer through constant-head boundaries and (2) decrease leakage from the valley unit of the Sauk River Valley aquifer to the streams. No appreciable differences were discernible between the simulated steady-state contributing areas to wells with 1998 pumpage and those with the projected pumpage.

  4. Recalibration of a ground-water flow model of the Mississippi River Valley alluvial aquifer of northeastern Arkansas, 1918-1998, with simulations of water levels caused by projected ground-water withdrawals through 2049

    USGS Publications Warehouse

    Reed, Thomas B.

    2003-01-01

    the model. Areally specified recharge rates ranged from 0 to about 30 inches and total recharge increased from 1972 to 1998 by a factor of about four. Water levels caused by projected ground-water withdrawals were simulated using the calibrated model. Simulations represented a period of 50 years into the future in three scenarios with either unchanged pumpage, pumpage increased by historic trends, or pumpage increased by historic trends except in two areas of the Grand Prairie. If pumping remains at 1997 rates, this produces extreme water-level declines (areas where model cells have gone dry or where the water level in the aquifer is equal to or less than the original saturated thickness, assuming confined conditions in the aquifer everywhere in the formation in predevelopment times) in the aquifer in two areas of the aquifer (one in the Grand Prairie area between the Arkansas and White Rivers and the other west of Crowleys Ridge along the Cache River) with about 400 square miles going dry. Increasing the pumping rates to that which would be projected using historic data led to increased extreme water-level declines in both areas with about 1,300 square miles going dry. Declines in both scenarios generally occurred most rapidly between 2009 and 2019. Reducing the pumping rates to 90 percent of that used for projected historic rates in areas between the Arkansas and White Rivers relating to two diversion projects of the U.S. Army Corps of Engineers and other agencies did little to decrease the extreme water-level declines. However, these pumpage reductions are small (amounting to about 16 percent of the reductions that could result from implementation of these diversion projects).

  5. New Data on Land Subsidence Phenomena Due to Excessive Ground Water Withdrawal in the Western Thessaly Basin, Central Greece

    NASA Astrophysics Data System (ADS)

    Sideri, D.; Rozos, D.; Loupasakis, C.; Kotsanis, D.

    2012-04-01

    The Western Thessaly basin is a major plain which is located in Central Greece. During the last decades this area exhibits an intensive development, mainly based on the agricultural economy. Due to that agricultural development, several thousand boreholes have been drilled for irrigation purposes. The overexploitation of the ground water, in the wider area, has triggered the manifestation of land subsidence phenomena. These phenomena were firstly observed in 2002 in the Stavros and Farsala sites (southeast part of the Western Thessaly basin), in the form of various surface ruptures. In 2009 similar phenomena appeared in Agios Georgios village and in 2011 in Anohori and Katohori villages, which are located between Farsala and Stavros towns. The geological environment of the research area consists of terrestrial sands and gravels horizons Pleistocene in age, with brown and grey clayey silt to silty clay intercalations. These alternations of permeable coarse-grained deposits (aquifers) with impermeable to low permeability strata (aquitards) create a number of successive semi-confined to confined aquifers, sometimes artesians. Land subsidence deformations were noticed both along the margins as well as in the inner part of the basin. Surface ruptures are observed along the margins of the basin where the bedrock outcrops and generally in areas where the thickness of the Pleistocene deposits appear to be small. On the contrary, in the parts of the basin with thick deposits, the subsidence of the Pleistocene formations can be noticed by the extraction of the water wells pipes. During this research a detailed geotechnical and hydrogeological survey was carried out covering the study area. Several hundreds of boreholes, drilled in the frame of previous geological-geotechnical investigations, were analyzed and interpreted, along with previous data, referring to the stratigraphy of the study area. As a result, the highly compressible units, which may be responsible for

  6. Ground-water appraisal of sand plains in Benton, Sherburne, Stearns, and Wright counties, central Minnesota

    USGS Publications Warehouse

    Lindholm, Gerald F.

    1980-01-01

    Both modeled areas will support additional withdrawals, but caution must be exercised because lowering ground-water levels will also lower lake levels and reduce streamflow. In some areas, aquifer dewatering will reduce individual well yields.

  7. Simulated effects of ground-water withdrawals and artificial recharge on discharge to streams, springs, and riparian vegetation in the Sierra Vista Subwatershed of the Upper San Pedro Basin, southeastern Arizona

    USGS Publications Warehouse

    Leake, Stanley A.; Pool, Donald R.; Leenhouts, James M.

    2008-01-01

    In the context of ground-water resources, “capture” or “streamflow depletion” refers to withdrawal-induced changes in inflow to or outflow from an aquifer. These concepts are helpful in understanding the effects of long-term development of ground-water resources. For the Upper San Pedro Basin in Arizona, USA and Sonora, Mexico, a recently developed ground-water flow model is available to help quantify capture of water from the river and riparian system. A common method of analysis is to compute curves of capture and aquifer-storage change for a range of time at select points of interest. This study, however, presents results of a method to show spatial distributions of total change in inflow and outflow from withdrawal or injection for select times of interest. The mapped areal distributions show the effect of a single well in terms of the ratio of the change in boundary flow rate to rate of withdrawal or injection by the well. To the extent that the system responds linearly to ground-water withdrawal or injection, fractional responses in the mapped distributions can be used to quantify response for any withdrawal or injection rate. Capture distributions calculated using the Upper San Pedro model include response to (1) withdrawal in the lower basin-fill aquifer for times of 10 and 50 years following the initiation of pumping from predevelopment conditions and (2) artificial recharge to the water table in the area underlain by the lower basin-fill aquifer after 10 and 50 years. The mapped distributions show that response to withdrawals and injections is greatest near the river/riparian system. Presence of clay layers in the vertical interval between withdrawal locations and the river/riparian system, however, can delay the response.

  8. Estimating irrigation water use and withdrawal of ground water on the High Plains, U.S.A.

    USGS Publications Warehouse

    Wray, J.R.

    1982-01-01

    In four decades following the Dust Bowl days of the 1930's, extensive areas of dry farming and rangeland on the semi-arid U.S. High Plains were transformed into a vast region of irrigated oases, producing meat and grain for much of the world. The agricultural economy has experienced such rapid growth in part because of the availability of ground water and because of development of new irrigation technology to use that water for agriculture. However, more water is being used than is being replaced. To estimate both the volume of water withdrawn and the regional scope of the problem a technique has been developed that combines multispectral data from Earth-orbiting satellite with known pumpage data for the same growing season. The location and extent of irrigated cropland-some with different crops watered at different times-is inventoried using computer-assisted analysis of the data from Landsat. The amount of water used is estimated by multiplying and summing surface area of irrigated agriculture and the average measured pumpage from sampled sites. Published findings to date are cited in the Selected References. All suggest transferability of a promising technology to the study of land transformation processes elsewhere. ?? 1983.

  9. Simulation of the ground-water flow system and proposed withdrawals in the northern part of Vekol Valley, Arizona

    USGS Publications Warehouse

    Hollett, K.J.; Marie, J.R.

    1987-01-01

    Pursuant to the Ak-Chin Indian Community Water Rights Settlement Act (Public Law 95-328-enacted on July 28, 1978) a study was undertaken to assess the effect of proposed groundwater withdrawal from Federal lands near the reservation. The first area to be evaluated was the northern part of the Vekol Valley. The evaluation was made using a numerical model based on detailed geohydrologic concepts developed during the study. The numerical model, which was calibrated to steady-state and transient groundwater conditions in the northern part of Vekol Valley, adequately duplicated the conceptual model and was used to estimate the effect of withdrawing approximately 174,000 acre-ft from the system during a 25-yr period. At the end of the 25-yr period, the water level was drawn down an average of about 95 ft, and about 150,5000 acre-ft of water was removed from storage. The 150,500 acre-ft of water represents 43% of the estimated recoverable groundwater in storage. (Author 's abstract)

  10. Simulated response of the High Plains aquifer to ground-water withdrawals in the Upper Republican Natural Resources District, Nebraska

    USGS Publications Warehouse

    Peckenpaugh, J.M.; Kern, R.A.; Dugan, J.T.; Kilpatrick, J.M.

    1995-01-01

    The U.S. Geological Survey, in cooperation with the National Soil Tilth Laboratory of the U.S. Department of Agriculture, Agricultural Research Service, conducted a study as part of the multi- scale, interagency Management Systems Evaluation Area (MSEA) program to evaluate the effects of agricultural management (farming) systems on water quality. Data on surface flow, tileflow, and streamflow in the Walnut Creek watershed just south of Ames, Iowa, were collected during April 1991-September 1993 at five sites with drainage areas ranging from 366 to 5,130 hectares. Precipitation, flow discharge, and concentration, loads, and yields of nitrate as nitrogen, atrazine, and metolachlor were analyzed to relate the transport of agricultural chemicals to major water-flow processes and to examine and transport differences among three subwatersheds. Antecedent conditions and basin-characteristic differences had significant effects on the flow response from the subwatersheds. Monthly streamflow-to- precipitation ratios were greater than 1.0, as a result of snowmelt, and negative when streamflow was lost to the ground-water system in the downstream subwatershed. Dry antecedent conditions resulted in ratios less than 0.3 (July 1992), whereas wet antecedent conditions resulted in ratios from 0.7 to almost 1.0 (July 1993) during months with similar large rainfall amounts. Most of the streamflow from the upland subwatersheds came from tileflow. Surface flow (surface runoff, interflow, and return flow0 was highly variable and intermittent, usually lasting for only a few days after a storm, although it could be the dominant source of flow when stormflow was large. Tileflow was less variable and much more persistent, ceasing only after prolonged dry periods. Large quantities of nitrate as nitrogen were transported in Walnut Creek, with concen- trations often greater than the Maximum Contaminant Level of 10 milligrams per liter established by the U.S. Environmental Protection Agency for

  11. 78 FR 28163 - Zentox Corporation; Withdrawal of Food Additive Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-14

    ... Register of September 3, 2008 (73 FR 51490), we announced that Zentox Corp., c/o Burdock Group, 801 North... HUMAN SERVICES Food and Drug Administration 21 CFR Part 173 Zentox Corporation; Withdrawal of Food Additive Petition AGENCY: Food and Drug Administration, HHS. ACTION: Notice of withdrawal. SUMMARY:...

  12. Ground Water

    USGS Publications Warehouse

    ,

    1986-01-01

    Some water underlies the Earth's surface almost everywhere, beneath hills, mountains,plains, and deserts. It's not always accessible, or fresh enough for use without treatment, and it's sometimes difficult to locate or to measure and descri be. This water may occur close to the land surface, as in a marsh, or it may lie many hundreds of feet below the surface, as in some arid areas of the West. Water at very shallow depths might be just a few hours old ; at moderate depth, it may be 100 years old; and at great depth or after having flowed long distances from places of entry, water may be several thousands of years old . Water under the Earth's surface is called ground water.

  13. Ground-water conditions in Georgia, 1999

    USGS Publications Warehouse

    Cressler, Alan M.

    2000-01-01

    Ground-water conditions in Georgia during 1999 and for the period of record were evaluated using data from U.S. Geological Survey ground-water-level and ground-water-quality monitoring networks. Data for 1999 included in this report are from continuous water-level records from 130 wells and chloride analyses from 14 wells. Data from one well is incomplete because data collection was discontinued. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standards. Ground-water-level and ground-water-quality data are essential for water assessment and management. Ground-water-level fluctuations and trends can be used to estimate changes in aquifer storage resulting from the effects of ground-water withdrawal and recharge from precipitation. These data can be used to address water-management needs and to evaluate the effects of management and conservation programs. As part of the ground-water investigations conducted by the U.S. Geological Survey (USGS), in cooperation with the State of Georgia and city and county governments, a Statewide water-level-measurement program was started in 1938. Initially, this program consisted of an observation-well network in the coastal area of Georgia to monitor variations in ground-water storage and quality. Additional wells were later included in areas where data could be used to aid in water resources development and management. During 1999, periodic water-level measurements were made in 46 wells, and continuous water-level measurements were obtained from 165 wells. Continuous water-level records were obtained using analog (pen and chart

  14. Reassessment of Ground-Water Recharge and Simulated Ground-Water Availability for the Hawi Area of North Kohala, Hawaii

    USGS Publications Warehouse

    Oki, Delwyn S.

    2002-01-01

    An estimate of ground-water availability in the Hawi area of north Kohala, Hawaii, is needed to determine whether ground-water resources are adequate to meet future demand within the area and other areas to the south. For the Hawi area, estimated average annual recharge from infiltration of rainfall, fog drip, and irrigation is 37.5 million gallons per day from a daily water budget. Low and high annual recharge estimates for the Hawi area that incorporate estimated uncertainty are 19.9 and 55.4 million gallons per day, respectively. The recharge estimates from this study are lower than the recharge of 68.4 million gallons per day previously estimated from a monthly water budget. Three ground-water models, using the low, intermediate, and high recharge estimates (19.9, 37.5, and 55.4 million gallons per day, respectively), were developed for the Hawi area to simulate ground-water levels and discharges for the 1990?s. To assess potential ground-water availability, the numerical ground-water flow models were used to simulate the response of the freshwater-lens system to withdrawals at rates in excess of the average 1990?s withdrawal rates. Because of uncertainty in the recharge estimate, estimates of ground-water availability also are uncertain. Results from numerical simulations indicate that for appropriate well sites, depths, and withdrawal rates (1) for the low recharge estimate (19.9 million gallons per day) it may be possible to develop an additional 10 million gallons per day of fresh ground water from the Hawi area and maintain a freshwater-lens thickness of 160 feet near the withdrawal sites, (2) for the intermediate recharge estimate (37.5 million gallons per day) it may be possible to develop an additional 15 million gallons per day of fresh ground water from the Hawi area and maintain a freshwater-lens thickness of 190 feet near the withdrawal sites, and (3) for the high recharge estimate (55.4 million gallons per day) it may be possible to develop at

  15. Ground water in Oklahoma

    USGS Publications Warehouse

    Leonard, A.R.

    1960-01-01

    One of the first requisites for the intelligent planning of utilization and control of water and for the administration of laws relating to its use is data on the quantity, quality, and mode of occurrence of the available supplies. The collection, evaluation and interpretation, and publication of such data are among the primary functions of the U.S. Geological Survey. Since 1895 the Congress has made appropriations to the Survey for investigation of the water resources of the Nation. In 1929 the Congress adopted the policy of dollar-for-dollar cooperation with the States and local governmental agencies in water-resources investigations of the U.S. Geological Survey. In 1937 a program of ground-water investigations was started in cooperation with the Oklahoma Geological Survey, and in 1949 this program was expanded to include cooperation with the Oklahoma Planning and Resources Board. In 1957 the State Legislature created the Oklahoma Water Resources Board as the principal State water agency and it became the principal local cooperator. The Ground Water Branch of the U.S. Geological Survey collects, analyzes, and evaluates basic information on ground-water resources and prepares interpretive reports based on those data. Cooperative ground-water work was first concentrated in the Panhandle counties. During World War II most work was related to problems of water supply for defense requirements. Since 1945 detailed investigations of ground-water availability have been made in 11 areas, chiefly in the western and central parts of the State. In addition, water levels in more than 300 wells are measured periodically, principally in the western half of the State. In Oklahoma current studies are directed toward determining the source, occurrence, and availability of ground water and toward estimating the quantity of water and rate of replenishment to specific areas and water-bearing formations. Ground water plays an important role in the economy of the State. It is

  16. Ground-Water Hydrology of the Upper Deschutes Basin, Oregon

    USGS Publications Warehouse

    Gannett, Marshall W.; Lite, Kenneth E.; Morgan, David S.; Collins, Charles A.

    2001-01-01

    The upper Deschutes Basin is among the fastest growing regions in Oregon. The rapid population growth has been accompanied by increased demand for water. Surface streams, however, have been administratively closed to additional appropriation for many years, and surface water is not generally available to support new development. Consequently, ground water is being relied upon to satisfy the growth in water demand. Oregon water law requires that the potential effects of ground-water development on streamflow be evaluated when considering applications for new ground-water rights. Prior to this study, hydrologic understanding has been insufficient to quantitatively evaluate the connection between ground water and streamflow, and the behavior of the regional ground-water flow system in general. This report describes the results of a hydrologic investigation undertaken to provide that understanding. The investigation encompasses about 4,500 square miles of the upper Deschutes River drainage basin.A large proportion of the precipitation in the upper Deschutes Basin falls in the Cascade Range, making it the principal ground-water recharge area for the basin. Water-balance calculations indicate that the average annual rate of ground- water recharge from precipitation is about 3,500 ft3/s (cubic feet per second). Water-budget calculations indicate that in addition to recharge from precipitation, water enters the ground-water system through interbasin flow. Approximately 800 ft3/s flows into the Metolius River drainage from the west and about 50 ft3/s flows into the southeastern part of the study area from the Fort Rock Basin. East of the Cascade Range, there is little or no ground-water recharge from precipitation, but leaking irrigation canals are a significant source of artificial recharge north of Bend. The average annual rate of canal leakage during 1994 was estimated to be about 490 ft3/s. Ground water flows from the Cascade Range through permeable volcanic rocks

  17. Hydrology and Simulation of Ground-Water Flow in the Tooele Valley Ground-Water Basin, Tooele County, Utah

    USGS Publications Warehouse

    Stolp, Bernard J.; Brooks, Lynette E.

    2009-01-01

    and bicarbonate. Dissolved-solids concentration increases in the central and northern parts of Tooele Valley, at the distal ends of the ground-water flow paths. Increased concentration is due mainly to greater amounts of sodium and chloride. Deuterium and oxygen-18 values indicate water recharged primarily from precipitation occurs throughout the ground-water basin. Ground water with the highest percentage of recharge from irrigation exists along the eastern margin of Tooele Valley, indicating negligible recharge from the adjacent consolidated rock. Tritium and tritiogenic helium-3 concentrations indicate modern water exists along the flow paths originating in the Oquirrh Mountains between Settlement and Pass Canyons and extending between the steep hydraulic gradient areas at Tooele Army Depot and Erda. Pre-modern water exists in areas east of Erda and near Stansbury Park. Using the change in tritium along the flow paths originating in the Oquirrh Mountains, a first-order estimate of average linear ground-water velocity for the general area is roughly 2 to 5 feet per day. A numerical ground-water flow model was developed to simulate ground-water flow in the Tooele Valley ground-water basin and to test the conceptual understanding of the ground-water system. Simulating flow in consolidated rock allows recharge and withdrawal from wells in or near consolidated rock to be simulated more accurately. In general, the model accurately simulates water levels and water-level fluctuations and can be considered an adequate tool to help determine the valley-wide effects on water levels of additional ground-water withdrawal and changes in water use. The simulated increase in storage during a projection simulation using 2003 withdrawal rates and average recharge indicates that repeated years of average precipitation and recharge conditions do not completely restore the system after multiple years of below-normal precipitation. In the similar case where precipitation is 90

  18. Simulation of the Regional Ground-Water-Flow System and Ground-Water/Surface-Water Interaction in the Rock River Basin, Wisconsin

    USGS Publications Warehouse

    Juckem, Paul F.

    2009-01-01

    A regional, two-dimensional, areal ground-water-flow model was developed to simulate the ground-water-flow system and ground-water/surface-water interaction in the Rock River Basin. The model was developed by the U.S. Geological Survey (USGS), in cooperation with the Rock River Coalition. The objectives of the regional model were to improve understanding of the ground-water-flow system and to develop a tool suitable for evaluating the effects of potential regional water-management programs. The computer code GFLOW was used because of the ease with which the model can simulate ground-water/surface-water interactions, provide a framework for simulating regional ground-water-flow systems, and be refined in a stepwise fashion to incorporate new data and simulate ground-water-flow patterns at multiple scales. The ground-water-flow model described in this report simulates the major hydrogeologic features of the modeled area, including bedrock and surficial aquifers, ground-water/surface-water interactions, and ground-water withdrawals from high-capacity wells. The steady-state model treats the ground-water-flow system as a single layer with hydraulic conductivity and base elevation zones that reflect the distribution of lithologic groups above the Precambrian bedrock and a regionally significant confining unit, the Maquoketa Formation. In the eastern part of the Basin where the shale-rich Maquoketa Formation is present, deep ground-water flow in the sandstone aquifer below the Maquoketa Formation was not simulated directly, but flow into this aquifer was incorporated into the GFLOW model from previous work in southeastern Wisconsin. Recharge was constrained primarily by stream base-flow estimates and was applied uniformly within zones guided by regional infiltration estimates for soils. The model includes average ground-water withdrawals from 1997 to 2006 for municipal wells and from 1997 to 2005 for high-capacity irrigation, industrial, and commercial wells. In addition

  19. Development and calibration of a ground-water flow model for the Sparta Aquifer of southeastern Arkansas and north-central Louisiana and simulated response to withdrawals, 1998-2027

    USGS Publications Warehouse

    McKee, Paul W.; Clark, Brian R.

    2003-01-01

    The Sparta aquifer, which consists of the Sparta Sand, in southeastern Arkansas and north-central Louisiana is a major water resource and provides water for municipal, industrial, and agricultural uses. In recent years, the demand in some areas has resulted in withdrawals from the Sparta aquifer that substantially exceed replenishment of the aquifer. Considerable drawdown has occurred in the potentiometric surface forming regional cones of depression as water is removed from storage by withdrawals. These cones of depression are centered beneath the Grand Prairie area and the cities of Pine Bluff and El Dorado in Arkansas, and Monroe in Louisiana. The rate of decline for hydraulic heads in the aquifer has been greater than 1 foot per year for more than a decade in much of southern Arkansas and northern Louisiana where hydraulic heads are now below the top of the Sparta Sand. Continued hydraulic-head declines have caused water users and managers alike to question the ability of the aquifer to supply water for the long term. Concern over protecting the Sparta aquifer as a sustainable resource has resulted in a continued, cooperative effort by the Arkansas Soil and Water Conservation Commission, U.S. Army Corps of Engineers, and the U.S. Geological Survey to develop, maintain, and utilize numerical ground-water flow models to manage and further analyze the ground-water system. The work presented in this report describes the development and calibration of a ground-water flow model representing the Sparta aquifer to simulate observed hydraulic heads, documents major differences in the current Sparta model compared to the previous Sparta model calibrated in the mid-1980's, and presents the results of three hypothetical future withdrawal scenarios. The current Sparta model-a regional scale, three-dimensional numerical ground-water flow model-was constructed and calibrated using available hydrogeologic, hydraulic, and water-use data from 1898 to 1997. Significant changes

  20. Ground water and energy

    SciTech Connect

    Not Available

    1980-11-01

    This national workshop on ground water and energy was conceived by the US Department of Energy's Office of Environmental Assessments. Generally, OEA needed to know what data are available on ground water, what information is still needed, and how DOE can best utilize what has already been learned. The workshop focussed on three areas: (1) ground water supply; (2) conflicts and barriers to ground water use; and (3) alternatives or solutions to the various issues relating to ground water. (ACR)

  1. Simulated effects of projected ground-water withdrawals in the Floridan aquifer system, greater Orlando metropolitan area, east-central Florida

    USGS Publications Warehouse

    Murray, Louis C., Jr.; Halford, Keith J.

    1999-01-01

    Ground-water levels in the Floridan aquifer system within the greater Orlando metropolitan area are expected to decline because of a projected increase in the average pumpage rate from 410 million gallons per day in 1995 to 576 million gallons per day in 2020. The potential decline in ground-water levels and spring discharge within the area was investigated with a calibrated, steady-state, ground-water flow model. A wetter-than-average condition scenario and a drought-condition scenario were simulated to bracket the range of water-levels and springflow that may occur in 2020 under average rainfall conditions. Pumpage used to represent the drought-condition scenario totaled 865 million gallons per day, about 50 percent greater than the projected average pumpage rate in 2020. Relative to average 1995 steady-state conditions, drawdowns simulated in the Upper Floridan aquifer exceeded 10 and 25 feet for wet and dry conditions, respectively, in parts of central and southwest Orange County and in north Osceola County. In Seminole County, drawdowns of up to 20 feet were simulated for dry conditions, compared with 5 to 10 feet simulated for wet conditions. Computed springflow was reduced by 10 percent for wet conditions and by 38 percent for dry conditions, with the largest reductions (28 and 76 percent) occurring at the Sanlando Springs group. In the Lower Floridan aquifer, drawdowns simulated in southwest Orange County exceeded 20 and 40 feet for wet and dry conditions, respectively.

  2. Simulated Effects of Projected 2010 Withdrawals on Ground-Water Flow and Water Levels in the New Jersey Coastal Plain - A Task of the New Jersey Water Supply Plan, 2006 Revision

    USGS Publications Warehouse

    Gordon, Alison D.

    2007-01-01

    A ground-water flow model previously developed as part of a Regional Aquifer System Analysis (RASA) of the New Jersey Coastal Plain was used to simulate ground-water flow in eight major confined aquifers to help evaluate ground-water resources in support of the New Jersey Department of Environmental Protection's revision of the New Jersey State Water Supply Plan. This model was calibrated to 1998 steady-state and transient conditions. Withdrawals at wells in operation in 1998 were varied in three scenarios to evaluate their effects on flow directions, water levels, and water budgets in the confined aquifers. The scenarios used to predict changes in pumpage from 1998 to 2010 were based on (1) a continuation of 1990-99 trends in water use, (2) public-supply withdrawals estimated from county population projections, and (3) restricted withdrawals in Water-Supply Critical Areas. Total withdrawals in these three scenarios were approximately 366, 362, and 355 million gallons per day, respectively. The results of these simulations are used by New Jersey water-management officials to help address water-supply concerns for the State. In the revision of the New Jersey State Water Supply Plan, the eight major confined aquifers of the New Jersey Coastal Plain and their outcrop areas are divided into 41 hydrologic budget areas (HBAs). Simulation results were used to assess the effects of changing ground-water withdrawals on water levels and the flow budgets in each budget area. Simulation results for each scenario were compared with 1998 (baseline) simulated water levels and flow budgets. The 41 hydrologic budget areas are in areas of large ground-water withdrawals, water-level declines, and (or) saltwater-intrusion potential. Their boundaries are based on various hydrologic, geohydrologic, and withdrawal conditions, such as aquifer extent, location of the 250-milligram-per-liter isochlor, aquifer outcrop area, and ground-water divides. The budget areas include primarily the

  3. Ground-water conditions in Georgia, 1997

    USGS Publications Warehouse

    Cressler, A.M.

    1998-01-01

    Ground-water conditions in Georgia during 1997 and for the period of record were evaluated using data from ground-water-level and ground-water-quality monitoring networks. Data for 1997 included in this report are from continuous water-level records from 71 wells and chloride analyses from 14 wells. In 1997, annual mean ground-water levels in Georgia ranged from 6.2 feet (ft) lower to 5.6 ft higher than in 1996. Of the 71 wells summarized in this report, 23 wells had annual mean water levels that were higher, 35 wells had annual mean water levels that were lower, and 11 wells had annual mean water levels that were about the same in 1997 as during 1996. Data for two wells are incomplete because data collection was discontinued at one well, and the equipment was vandalized at one well. Record-low daily mean water levels were recorded in six wells tapping the Upper Floridan aquifer, one well tapping the Caliborne aquifer, two wells tapping the Clayton aquifer, and three wells tapping Cretaceous aquifers. These record lows were from 0.2 to 5.6 ft lower than previous record lows. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standard. Ground-water-level and ground-water-quality data are essential for water assessment and management. Ground-water-level fluctuations and trends can be used to estimate changes in aquifer storage resulting from the effects of ground-water withdrawal and recharge from precipitation. These data can be used to address water-management needs and to evaluate the effects of management and conservation programs. As part of the ground-water

  4. Death Valley regional ground-water flow system, Nevada and California -- hydrogeologic framework and transient ground-water flow model

    USGS Publications Warehouse

    : Belcher, Wayne R.

    2004-01-01

    provided by acquiring additional data, by reevaluating existing data using current technology and concepts, and by refining earlier interpretations to reflect the current understanding of the regional ground-water flow system. Ground-water flow in the Death Valley region is composed of several interconnected, complex ground-water flow systems. Ground-water flow occurs in three subregions in relatively shallow and localized flow paths that are superimposed on deeper, regional flow paths. Regional ground-water flow is predominantly through a thick Paleozoic carbonate rock sequence affected by complex geologic structures from regional faulting and fracturing that can enhance or impede flow. Spring flow and evapotranspiration (ET) are the dominant natural ground-water discharge processes. Ground water also is withdrawn for agricultural, commercial, and domestic uses. Ground-water flow in the DVRFS was simulated using MODFLOW-2000, a 3D finite-difference modular ground-water flow modeling code that incorporates a nonlinear least-squares regression technique to estimate aquifer parameters. The DVRFS model has 16 layers of defined thickness, a finite-difference grid consisting of 194 rows and 160 columns, and uniform cells 1,500 m on each side. Prepumping conditions (before 1913) were used as the initial conditions for the transient-state calibration. The model uses annual stress periods with discrete recharge and discharge components. Recharge occurs mostly from infiltration of precipitation and runoff on high mountain ranges and from a small amount of underflow from adjacent basins. Discharge occurs primarily through ET and spring discharge (both simulated as drains) and water withdrawal by pumping and, to a lesser amount, by underflow to adjacent basins, also simulated by drains. All parameter values estimated by the regression are reasonable and within the range of expected values. The simulated hydraulic heads of the final calibrated transient model gener

  5. Hydrogeology and simulated effects of ground-water withdrawals from the Floridan aquifer system in Lake County and in the Ocala National Forest and vicinity, north-central Florida

    USGS Publications Warehouse

    Knowles, Leel; O'Reilly, Andrew M.; Adamski, James C.

    2002-01-01

    The hydrogeology of Lake County and the Ocala National Forest in north-central Florida was evaluated (1995-2000), and a ground-water flow model was developed and calibrated to simulate the effects of both present day and future ground-water withdrawals in these areas and the surrounding vicinity. A predictive model simulation was performed to determine the effects of projected 2020 ground-water withdrawals on the water levels and flows in the surficial and Floridan aquifer systems. The principal water-bearing units in Lake County and the Ocala National Forest are the surficial and Floridan aquifer systems. The two aquifer systems generally are separated by the intermediate confining unit, which contains beds of lower permeability sediments that confine the water in the Florida aquifer system. The Floridan aquifer system has two major water-bearing zones (the Upper Floridan aquifer and the Lower Floridan aquifer), which generally are separated by one or two less-permeable confining units. The Floridan aquifer system is the major source of ground water in the study area. In 1998, ground-water withdrawals totaled about 115 million gallons per day in Lake County and 5.7 million gallons per day in the Ocala National Forest. Of the total ground water pumped in Lake County in 1998, nearly 50 percent was used for agricultural purposes, more than 40 percent for municipal, domestic, and recreation supplies, and less than 10 percent for commercial and industrial purposes. Fluctuations of lake stages, surficial and Floridan aquifer system water levels, and Upper Floridan aquifer springflows in the study area are highly related to cycles and distribution of rainfall. Long-term hydrographs for 9 lakes, 8 surficial aquifer system and Upper Floridan aquifer wells, and 23 Upper Floridan aquifer springs show the most significant increases in water levels and springflows following consecutive years with above-average rainfall, and significant decreases following consecutive years

  6. Ground Water Remediation Technologies

    EPA Science Inventory

    The USEPA's Ground Water and Ecosystems Restoration Division (GWERD) conducts research and provides technical assistance to support the development of strategies and technologies to protect and restore ground water, surface water, and ecosystems impacted by man-made and natural...

  7. GROUND WATER SAMPLING ISSUES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and
    remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  8. Ground water: a review.

    USGS Publications Warehouse

    Bredehoeft, J.D.

    1983-01-01

    There is growing documentation that a significant portion of the Nation's fresh ground water in the densely populated areas of the USA is contaminated. Because of the slow rates of ground-water movement, ground water once contaminated will remain so for decades, often longer. Cleanup of contaminated ground water is almost always expensive and often technically unfeasible; the expense is often prohibitive. -from Author

  9. Hydrogeologic Setting and Ground-Water Flow in the Leetown Area, West Virginia

    USGS Publications Warehouse

    Kozar, Mark D.; Weary, David J.; Paybins, Katherine S.; Pierce, Herbert A.

    2007-01-01

    avenues of ground-water flow. Prior to this investigation, the conceptual model of ground-water flow for the region focused primarily on bedding planes and strike-parallel faults and joints as controls on ground-water flow but did not recognize the importance of cross-strike faults and fracture zones that allow ground water to flow downgradient across or through less permeable geologic formations. Results of the ground-water flow simulation indicate that current operations at the Center do not substantially affect either streamflow (less than a 5-percent reduction in annual streamflow) or ground-water levels in the Leetown area under normal climatic conditions but potentially could have greater effects on streamflow during long-term drought (reduction in streamflow of approximately 14 percent). On the basis of simulation results, ground-water withdrawals based on the anticipated need for an additional 150 to 200 gal/min (gallons per minute) of water at the Center also would not seriously affect streamflow (less than 8 to 9 percent reduction in streamflow) or ground-water levels in the area during normal climatic conditions. During drought conditions, however, the effects of current ground-water withdrawals and anticipated additional withdrawals of 150 to 200 gal/min to augment existing supplies result in moderate to substantial declines in water levels of 0.5-1.2 feet (ft) in the vicinity of the Center's springs and production wells. Streamflow was predicted to be reduced locally by approximately 21 percent. Such withdrawals during a drought or prolonged period of below normal ground-water levels would result in substantial declines in the flow of the Center's springs and likely would not be sustainable for more than a few months. The drought simulated in this model was roughly equivalent to the more than 1-year drought that affected the region from November 1998 through February 2000. The potential reduction in streamflow is a result of capture of ground water tha

  10. Estimated effects of projected ground-water withdrawals on movement of the saltwater front in the Floridan aquifer, 1976-2000, west-central Florida

    USGS Publications Warehouse

    Wilson, William Edward

    1982-01-01

    encroachment could result from (1) ground-water development in the zone of transition and (2) deviations of local hydrogeologic conditions from average regional conditions.

  11. Geohydrology and Numerical Simulation of the Ground-Water Flow System of Kona, Island of Hawaii

    USGS Publications Warehouse

    Oki, Delwyn S.

    1999-01-01

    results indicate, however, that water levels do not strictly increase in an inland direction and that a ground-water divide exists within the buried dike complex. Data are not available, however, to verify model results in the area near and inland of the model-calculated ground-water divide. Three simulations to determine the effects of proposed withdrawals from the high water-level area on coastal discharge and water levels, relative to model-calculated, steady-state coastal discharge and water levels for 1997 withdrawal rates, show that the effects are widespread. During 1997, the total withdrawal of ground water from the high water-level area between Palani Junction and Holualoa was about 1 million gallons per day. Model results indicate that it may not be possible to withdraw 25.6 million gallons per day of freshwater from this area between Palani Junction and Holualoa, but that it may be possible to withdraw between 5 to 8 million gallons per day from the same area. For a proposed withdrawal rate of 5.0 million gallons per day uniformly distributed to 12 sites between Palani Junction and Holualoa, the model-calculated drawdown of 0.01 foot or more extends about 9 miles north-northwest and about 7 miles south of the proposed well sites. In all scenarios, freshwater coastal discharge is reduced by an amount equal to the additional freshwater withdrawal. Additional data needed to improve the understanding of the ground-water flow system in the Kona area include: (1) a wider spatial distribution and longer temporal distribution of water levels, (2) improved information about the subsurface geology, (3) independent estimates of hydraulic conductivity, (4) improved recharge estimates, and (5) information about the vertical distribution of salinity in ground water.

  12. Analysis of ground-water flow and saltwater encroachment in the shallow aquifer system of Cape May County, New Jersey

    USGS Publications Warehouse

    Spitz, Frederick J.

    1998-01-01

    Cape May County, New Jersey, is on a natural peninsula that is virtually surrounded by saltwater. A calibrated quasi-three-dimensional sharp-interface model was used to simulate ground-water flow in the shallow aquifer system under two water-supply-development alternatives for a 30-year planning period. The alternatives involve modest increases in withdrawals in combination with desalination of brackish ground water or inland relocation of wells. Simulation results indicate that projected withdrawals for the two alternatives can be sustained without significant additional saltwater encroachment over the planning period.

  13. Chemical contamination of ground water in India

    SciTech Connect

    Mohapatra, S.P.; Agnihoiri, N.P.

    1996-10-01

    Ground water is the main source of drinking water in rural areas and many urban areas in India. In addition, it has been increasingly used for irrigation in farmland. Contamination of ground water by persistent inorganic and organic chemicals has emerged as a major environmental concern in recent years. Nitrate, fluoride, heavy metals and organochlorine compounds are found to be major contaminants of ground water in different parts of the country. At many places the concentrations of these chemicals exceed national and international guideline values for drinking water. While large concentrations of heavy metals come from industrial sources, agricultural activities are responsible for ground water contamination by nitrate and organochlorine insecticides.

  14. COMPILATION OF GROUND-WATER MODELS

    EPA Science Inventory

    Ground-water modeling is a computer-based methodology for mathematical analysis of the mechanisms and controls of ground-water systems for the evaluation of policies, action, and designs that may affect such systems. n addition to satisfying scientific interest in the workings of...

  15. Ground Water in Hawaii

    USGS Publications Warehouse

    Gingerich, Stephen B.; Oki, Delwyn S.

    2000-01-01

    Ground water is one of Hawaii's most important natural resources. It is used for drinking water, irrigation, and domestic, commercial, and industrial needs. Ground water provides about 99 percent of Hawaii's domestic water and about 50 percent of all freshwater used in the State. Total ground water pumped in Hawaii was about 500 million gallons per day during 1995, which is less than 3 percent of the average total rainfall (about 21 billion gallons per day) in Hawaii. From this perspective, the ground-water resource appears ample; however, much of the rainfall runs off to the ocean in streams or returns to the atmosphere by evapotranspiration. Furthermore, ground-water resources can be limited because of water-quality, environmental, or economic concerns. Water beneath the ground surface occurs in two principal zones: the unsaturated zone and the saturated zone. In the unsaturated zone, the pore spaces in rocks contain both air and water, whereas in the saturated zone, the pore spaces are filled with water. The upper surface of the saturated zone is referred to as the water table. Water below the water table is referred to as ground water. Ground-water salinity can range from freshwater to that of seawater. Freshwater is commonly considered to be water with a chloride concentration less than 250 mg/L, and this concentration represents about 1.3 percent of the chloride concentration of seawater (19,500 mg/L). Brackish water has a chloride concentration between that of freshwater (250 mg/L) and saltwater (19,500 mg/L).

  16. Simulation of Transient Ground-Water Flow in the Valley-Fill Aquifers of the Upper Rockaway River Basin, Morris County, New Jersey

    USGS Publications Warehouse

    Gordon, Alison D.

    2002-01-01

    withdrawn from the valley-fill aquifers. In scenario 2, the additional 1 million gallons per day of withdrawals were made from a hypothetical well located in the upper aquifer about 250 feet from the river. In scenario 3, the additional withdrawals were made from a hypothetical well located in the lower aquifer about 1,750 feet from the river. Results of scenario 1 indicated that the difference between the streamflow depletion and withdrawals is small; increases in ground-water withdrawals from the valley-fill aquifers correspond to decreases in ground-water discharge to the Rockaway River of approximately the same amount. Results of scenario 2 and 3 indicated that a lag time could occur between the introduction of withdrawals and the full magnitude of the effects of the withdrawals on streamflow depletion. A lag time of about seven months occurred for scenario 2 with the well placed in the upper aquifer. A longer lag time of more than 1.5 years occurred with the well placed in the lower aquifer and separated from the upper aquifer by a confining unit (scenario 3). Extreme low flow in the Rockaway River is mostly base flow. A flow-duration analysis of the Rockaway River at the surface-water gaging station upstream from the Boonton Reservoir during the drought of 1961-66 indicated that streamflow from the upper Rockaway River Basin alone might not be sufficient to meet the minimum passing flow of 7 million gallons per day during a drought. Under similar drought conditions today, during 3.2 percent of the drought time, streamflow at this station upstream from the reservoir would be less than the minimum passing flow requirement downstream from the reservoir.

  17. Hydrology and Simulation of Ground-Water Flow, Lake Point, Tooele County, Utah

    USGS Publications Warehouse

    Brooks, Lynette E.

    2006-01-01

    Water for new residential development in Lake Point, Utah may be supplied by public-supply wells completed in consolidated rock on the east side of Lake Point. Ground-water flow models were developed to help understand the effect the proposed withdrawal will have on water levels, flowing-well discharge, spring discharge, and ground-water quality in the study area. This report documents the conceptual and numerical ground-water flow models for the Lake Point area. The ground-water system in the Lake Point area receives recharge from local precipitation and irrigation, and from ground-water inflow from southwest of the area. Ground water discharges mostly to springs. Discharge also occurs to evapotranspiration, wells, and Great Salt Lake. Even though ground water discharges to Great Salt Lake, dense salt water from the lake intrudes under the less-dense ground water and forms a salt-water wedge under the valley. This salt water is responsible for some of the high dissolved-solids concentrations measured in ground water in Lake Point. A steady-state MODFLOW-2000 ground-water model of Tooele Valley adequately simulates water levels, ground-water discharge, and ground-water flow direction observed in Lake Point in 1969 and 2002. Simulating an additional 1,650 acre-feet per year withdrawal from wells causes a maximum projected drawdown of about 550 feet in consolidated rock near the simulated wells and drawdown exceeding 80 feet in an area encompassing most of the Oquirrh Mountains east of Lake Point. Drawdown in most of Lake Point ranges from 2 to 10 ft, but increases to more than 40 feet in the areas proposed for residential development. Discharge to Factory Springs, flowing wells, evapotranspiration, and Great Salt Lake is decreased by about 1,100 acre-feet per year (23 percent). The U.S. Geological Survey SUTRA variable-density ground-water-flow model generates a reasonable approximation of 2002 dissolved-solids concentration when simulating 2002 withdrawals. At most

  18. Ground-Water Availability in the Wailuku Area, Maui, Hawai'i

    USGS Publications Warehouse

    Gingerich, Stephen B.

    2008-01-01

    Most of the public water supply in Maui, Hawai'i, is from a freshwater lens in the Wailuku area of the island. Because of population growth, ground-water withdrawals from wells in this area increased from less than 10 Mgal/d during 1970 to about 23 Mgal/d during 2006. In response to increased withdrawals from the freshwater lens in the Wailuku area, water levels declined, the transition zone between freshwater and saltwater became shallower, and the chloride concentrations of water pumped from wells increased. These responses led to concern over the long-term sustainability of withdrawals from existing and proposed wells. A three-dimensional numerical ground-water flow and transport model was developed to simulate the effects of selected withdrawal and recharge scenarios on water levels, on the transition zone between freshwater and saltwater, and on surface-water/ground-water interactions. The model was constructed using time-varying recharge, withdrawals, and ocean levels. Hydraulic characteristics used to construct the model were initially based on published estimates but ultimately were varied to obtain better agreement between simulated and measured water levels and salinity profiles in the modeled area during the period 1926-2006. Scenarios included ground-water withdrawal at 2006 and 1996 rates and locations with average recharge (based on 2000-04 land use and 1926-2004 rainfall) and withdrawal at redistributed rates and locations with several different recharge scenarios. Simulation results indicate that continuing 1996 and 2006 withdrawal distributions into the future results in decreased water levels, a thinner freshwater lens, increased salinity from pumped wells, and higher salinity at several current withdrawal sites. A redistributed withdrawal condition in which ground-water withdrawal was redistributed to maximize withdrawal and minimize salinities in the withdrawn water was determined. The redistributed withdrawal simulates 27.1 Mgal/d of withdrawal

  19. Georgia's Ground-Water Resources and Monitoring Network, 2008

    USGS Publications Warehouse

    ,

    2008-01-01

    Ground water is an abundant resource in Georgia, providing 1.45 billion gallons per day, or 22 percent, of the total freshwater used (including thermoelectric) in the State (Fanning, 2003). Contrasting geologic features and landforms of the physiographic provinces of Georgia affect the quantity and quality of ground water throughout the State. Most ground-water withdrawals are in the Coastal Plain in the southern one-half of the State, where aquifers are highly productive. For a more complete discussion of the State's ground-water resources, see Leeth and others (2005).

  20. Geology and ground-water resources of Uvalde County, Texas

    USGS Publications Warehouse

    Welder, F.A.; Reeves, R.D.

    1964-01-01

    Ground-water withdrawals from the Edwards and associated limestones in Uvalde County probably could be maintained indefinitely at a rate of about 200,000 acre-feet per year, provided that withdrawals north and west of the county were not increased. However, continued withdrawals at this rate-would cause wells in structurally high areas to go dry, and underflow into Medina County would cease. Furthermore, saline water might invade the fresh-water part of the

  1. Geohydrology and Numerical Simulation of the Ground-Water Flow System of Molokai, Hawaii

    USGS Publications Warehouse

    Oki, Delwyn S.

    1997-01-01

    southeast and 9 miles northwest from the well. In a third scenario, the withdrawal rate from an existing well near Kualapuu was increased by 0.826 million gallons per day. The model-calculated drawdown of 0.01 foot or more extends 6 miles southeast and 8 miles northwest from the well. In all scenarios, coastal discharge is reduced by an amount equal to the additional withdrawal. Additional data needed to improve the understanding of the ground-water flow system on Molokai include: (1) a wider spatial distribution and longer temporal distribution of water-levels, (2) independent estimates of hydraulic conductivity, (3) improved recharge estimates, (4) information about the vertical distribution of salinity in ground water, (5) streamflow data at additional sites, and (6) improved information about the subsurface geology.

  2. Hydrogeology and ground-water-flow simulation of the Cave Springs area, Hixson, Tennessee

    USGS Publications Warehouse

    Haugh, Connor J.

    2002-01-01

    The ground-water resource in the Cave Springs area is used by the Hixson Utility District as a water supply and is one of the more heavily stressed in the Valley and Ridge Physiographic Province. In 1999, ground-water withdrawals by the Hixson Utility District averaged about 6.4 million gallons per day (Mgal/d) from two pumping centers. The Hixson Utility District has historically withdrawn about 5.8 Mgal/d from wells at Cave Springs. In 1995 to meet increasing demand, an additional well field was developed at Walkers Corner, located about 3 miles northeast of Cave Springs. From 1995 through 2000, pumping from the first production well at Walkers Corner averaged about 1.8 Mgal/d. A second production well at Walkers Corner was approved for use in 2000. Hixson Utility District alternates the use of the two production wells at Walkers Corner except when drought conditions occur when they are used simultaneously. The second production well increased the capacity of the well field by an additional 2 Mgal/d. The aquifer framework in the study area consists of dense Paleozoic carbonate rocks with secondary permeability that are mantled by thick residual clay-rich regolith in most of the area and by coarse-grained alluvium in the valley of North Chickamauga Creek. Cave Springs, one of the largest springs in Tennessee, derives its flow from conduits in a carbonate rock (karst) aquifer. Production wells at Cave Springs draw water from these conduits. Production wells at Walkers Corner primarily draw water from gravel zones in the regolith near the top of rock. Transmissivities estimated from hydraulic tests conducted across the Cave Springs area span a range from 240 to 900,000 feet squared per day (ft2/d) with a median value of 5,200 ft2/d. Recharge to the aquifer occurs from direct infiltration of precipitation and from losing streams. Most recharge occurs during the winter and spring months. Computer modeling was used to provide a better understanding of the ground-water

  3. Summary of ground-water conditions in Arizona, 1987-90

    USGS Publications Warehouse

    Anning, D.W.; Duet, N.R.

    1994-01-01

    Annual ground-water withdrawals in Arizona were 2.9, 3.3, 3.6, and 3.4 million acre-feet for calendar years 1987. 1988, 1989, and 1990. The average annual ground-water withdrawal for Arizona from 1980-89 was 3.7 million acre-feet, which was the lowest average annual withdrawal for any decade since the 1940' s. Since 1947, annual ground-water withdrawals in Arizona were at the lowest rate in 1983 and at the second lowest rate in 1987. For 1987-90, the distribution of ground-water use was 11.8 percent for municipal, 8.3 percent for industnal, 72.6 percent for agriculture, and 7.3 percent for draining irrigated lands. More than 94 percent of the ground-water withdrawals in Arizona occurred in the Basin and Range lowlands province during 1987-90. This province contains the two areas with the largest rates of ground-water withdrawal in Arizona--the Salt River Valley and the lower Santa Cruz basin. The average annual ground-water withdrawal for the Salt River Valley from 1980-89 is 1,013,000 acre-feet, which is the lowest average annual withdrawal for any decade since the 1930 's. Ground-water withdrawals in the lower Santa Cruz basin during 1990 were the lowest on record since 1940. In 1985, the Central Arizona Project began delivering Colorado River water to central Arizona to mitigate ground-water overdraft. The Harquahala basin began receiving water from the Central Arizona Project in 1985. From 1985 to 1990, ground-water withdrawals decreased from 59,000 acre-feet to 2,000 acre-feet, and water levels rose as much as 70 feet.

  4. Ground-water and geohydrologic conditions in Queens County, Long Island, New York

    USGS Publications Warehouse

    Soren, Julian

    1971-01-01

    salty ground water toward the deepest parts of the cone of depression in central Queens County. Contamination of ground water is probably also occurring from leaking sewers and from pollutants leaking downward from the land surface. Thermal pollution of the ground water has occurred locally where ground water pumped for cooling uses is returned, with elevated temperatures, to the source aquifer through recharge wells. The quality of ground water in Queens County in 1967 was generally satisfactory for public-supply and most industrial uses. However, the rate and distribution of ground-water withdrawals in the county are leading to greater decline of the water table and to increasing contamination of the aquifers. No 'safe limit' on pumpage can be set for the county because limits on the effects of pumping have not been established. A safe limit, at the present stage of urbanization, could range from considerably less than the current average 60 mgd to considerably more over a wide-range of pumping effects and acceptable water quality. However, continued removal of fresh water from storage and deterioration of water quality reduces the value of the county's aquifers, not only for current supply, but also for additional supply to the county and other parts of New York City in times of drought or other emergency.

  5. MTBE concentrations in ground water in Pennsylvania

    USGS Publications Warehouse

    McAuley, Steven D.

    2003-01-01

    The distribution, concentrations, and detection frequency of methyl tert-butyl-ether (MTBE), a gasoline additive used in reformulated gasoline to improve air quality, were characterized in Pennsylvania?s ground water. Two sources of MTBE in ground water, the atmosphere and storage-tank release sites, were examined. An analysis of atmospheric MTBE concentrations shows that MTBE detections (MTBE greater than or equal to 0.2 micrograms per liter) in ground water are more likely the result of storage-tank releases than atmospheric deposition. A comparison of 86 ground-water samples near storage-tank releases and 359 samples from ambient ground water (not thought to be affected by point-source releases of MTBE or BTEX compounds) shows that samples within about 0.5 mile downgradient of storagetank release sites have significantly greater MTBE detection frequency than ambient ground-water samples. Aquifer type, land use, and the use of Reformulated Gasoline (RFG) are associated with high rates of occurrence of MTBE in ground water in Pennsylvania. Ground-water samples from wells in crystalline-rock aquifers near storage- tank release sites have a significantly greater MTBE detection frequency (57 percent) compared to other aquifers. Samples from wells in urban areas have a significantly greater MTBE detection frequency compared to ambient samples in agricultural and forested areas. Samples from the RFG-use areas in the five southeastern counties of Pennsylvania have a significantly greater MTBE detection frequency than samples outside of the RFG-use area. MTBE detection frequency of samples near storage- tank release sites in the RFG-use area (45 percent) are significantly greater than ambient samples in the RFG-use area.

  6. Availability of ground water in the area surrounding the Trident submarine construction facility, Kitsap County, Washington

    USGS Publications Warehouse

    Hansen, Arnold J.; Molenaar, Dee

    1976-01-01

    General information is presented on water resources--with emphasis on ground-water occurrence and availability--in that part of Kitsap County (referred to as Trident Impact Area) that would be most affected by the development of the Trident submarine construction facility at Bangor, Washington. The estimated 1970 water use in the study area averaged about 13 million gallons per day (mgd); of this amount about 9 mgd came from surface-water sources--from a large reservoir outside the study area--and about 4 mgd came from ground water pumped from two aquifers in the area. Anticipated water use soon will be about 18 to 21 mgd; virtually all the additional quantity required (about 5 to 8 mgd) above present use must come from ground-water sources. Preliminary evaluation of the aquifers suggests that an additional 1.5 mgd can be developed from the upper aquifer and 7 mgd from the lower aquifer. Existing wells tapping the lower aquifer might yield additional water and increase the total yield in the area by 3.5 mgd, and new wells drilled in selected areas could produce an additional 3.5 mgd from this aquifer. However, additional, large-scale ground-water withdrawal from the lower aquifer could induce saltwater intrusion into wells situated in coastal areas. (Woodard-USGS)

  7. 75 FR 39699 - Sterigenics International, Inc.; Withdrawal of Food Additive Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-12

    ... the Federal Register of November 30, 2004 (69 FR 69606), FDA announced that a food additive petition... HUMAN SERVICES Food and Drug Administration (formerly Docket No. 2004F-0455) Sterigenics International, Inc.; Withdrawal of Food Additive Petition AGENCY: Food and Drug Administration, HHS. ACTION:...

  8. Ground water in Utah's densely populated Wasatch Front area; the challenge and the choices

    USGS Publications Warehouse

    Price, Don

    1985-01-01

    320,000 acre-feet during 1979. Additional withdrawals from wells may cause water levels to decline, possibly leading to such problems as conflicts among water-right owners, increased pumping costs, land subsidence, and deterioration of ground-water quality. Some of these problems cannot be avoided if the principal ground-water reservoirs are to be fully used; however, management practices such as artificial ground-water recharge in intensively pumped areas may help to alleviate those problems.

  9. Ground-Water Availability from the Hawi Aquifer in the Kohala Area, Hawaii

    USGS Publications Warehouse

    Underwood, Mark R.; Meyer, William; Souza, William R.

    1995-01-01

    A ground-water study consisting of test-well drilling, aquifer tests, and numerical simulation was done to investigate ground-water availability in the basal part of the Hawi aquifer between the western drainage divide of Pololu Valley and Upolu Point in Kohala, Hawaii. The test-well drilling provided information on geology, water levels, water quality, vertical extent of the freshwater, and the thickness of the freshwater-saltwater transition zone in that aquifer. A total of 12 test wells were drilled at eight locations. Aquifer tests were done at five locations to estimate the hydraulic conductivity of the aquifer. Using information on the distribution of recharge, vertical extent of freshwater, hydraulic conductivity, and geometry of the basal aquifer, a numerical model was used to simulate the movement of water into, through, and out of the basal aquifer, and the effect of additional pumping on the water levels in the aquifer. Results of the modeling indicate that ground-water withdrawal of 20 million gallons per day above the existing withdrawal of 0.6 million gallons per day from the basal aquifer is hydrologically feasible, but that spacing, depth, and pumping rates of individual wells are important. If pumping is concentrated, the likelihood of saltwater intrusion is increased. The additional withdrawal of 20 million gallons per day would result in a reduction of ground-water discharge to the ocean by an amount equal to pumpage. Although model-calculated declines in water-level outside the area of pumping are small, pumping could cause some reduction of streamflow near the mouth of Pololu Stream.

  10. SUPERFUND GROUND WATER ISSUE: GROUND WATER SAMPLING FOR METALS ANALYSES

    EPA Science Inventory

    Filtration of ground-water samples for metals analysis is an issue identified by the Forum as a concern of Superfund decision-makers. Inconsistency in EPA Syperfund cleanup pracices occurs where one EPA Region implements a remedial action based on unfiltered ground-water samples,...

  11. Ground-Water Occurrence and Contribution to Streamflow, Northeast Maui, Hawaii

    USGS Publications Warehouse

    Gingerich, Stephen B.

    1999-01-01

    The study area lies on the northern flank of the East Maui Volcano (Haleakala) and covers about 129 square miles between the drainage basins of Maliko Gulch to the west and Makapipi Stream to the east. About 989 million gallons per day of rainfall and 176 million gallons per day of fog drip reaches the study area and about 529 million gallons per day enters the ground-water system as recharge. Average annual ground-water withdrawal from wells totals only about 3 million gallons per day; proposed (as of 1998) additional withdrawals total about 18 million gallons per day. Additionally, tunnels and ditches of an extensive irrigation network directly intercept at least 10 million gallons per day of ground water. The total amount of average annual streamflow in gaged stream subbasins upstream of 1,300 feet altitude is about 255 million gallons per day and the total amount of average annual base flow is about 62 million gallons per day. Six major surface-water diversion systems in the study area have diverted an average of 163 million gallons per day of streamflow (including nearly all base flow of diverted streams) for irrigation and domestic supply in central Maui during 1925-97. Fresh ground water is found in two main forms. West of Keanae Valley, ground-water flow appears to be dominated by a variably saturated system. A saturated zone in the uppermost rock unit, the Kula Volcanics, is separated from a freshwater lens near sea level by an unsaturated zone in the underlying Honomanu Basalt. East of Keanae Valley, the ground-water system appears to be fully saturated above sea level to altitudes greater than 2,000 feet. The total average annual streamflow of gaged streams west of Keanae Valley is about 140 million gallons per day at 1,200 feet to 1,300 feet altitude. It is not possible to estimate the total average annual streamflow at the coast. All of the base flow measured in the study area west of Keanae Valley represents ground-water discharge from the high

  12. Hydrogeology and Simulation of Regional Ground-Water-Level Declines in Monroe County, Michigan

    USGS Publications Warehouse

    Reeves, Howard W.; Wright, Kirsten V.; Nicholas, J.R.

    2004-01-01

    Observed ground-water-level declines from 1991 to 2003 in northern Monroe County, Michigan, are consistent with increased ground-water demands in the region. In 1991, the estimated ground-water use in the county was 20 million gallons per day, and 80 percent of this total was from quarry dewatering. In 2001, the estimated ground-water use in the county was 30 million gallons per day, and 75 percent of this total was from quarry dewatering. Prior to approximately 1990, the ground-water demands were met by capturing natural discharge from the area and by inducing leakage through glacial deposits that cover the bedrock aquifer. Increased ground-water demand after 1990 led to declines in ground-water level as the system moves toward a new steady-state. Much of the available natural discharge from the bedrock aquifer had been captured by the 1991 conditions, and the response to additional withdrawals resulted in the observed widespread decline in water levels. The causes of the observed declines were explored through the use of a regional ground-water-flow model. The model area includes portions of Lenawee, Monroe, Washtenaw, and Wayne Counties in Michigan, and portions of Fulton, Henry, and Lucas Counties in Ohio. Factors, including lowered water-table elevations because of below average precipitation during the time period (1991 - 2001) and reduction in water supply to the bedrock aquifer because of land-use changes, were found to affect the regional system, but these factors did not explain the regional decline. Potential ground-water capture for the bedrock aquifer in Monroe County is limited by the low hydraulic conductivity of the overlying glacial deposits and shales and the presence of dense saline water within the bedrock as it dips into the Michigan Basin to the west and north of the county. Hydrogeologic features of the bedrock and the overlying glacial deposits were included in the model design. An important step of characterizing the bedrock aquifer was the

  13. Ground-Water Recharge in Minnesota

    USGS Publications Warehouse

    Delin, G.N.; Falteisek, J.D.

    2007-01-01

    'Ground-water recharge' broadly describes the addition of water to the ground-water system. Most water recharging the ground-water system moves relatively rapidly to surface-water bodies and sustains streamflow, lake levels, and wetlands. Over the long term, recharge is generally balanced by discharge to surface waters, to plants, and to deeper parts of the ground-water system. However, this balance can be altered locally as a result of pumping, impervious surfaces, land use, or climate changes that could result in increased or decreased recharge. * Recharge rates to unconfined aquifers in Minnesota typically are about 20-25 percent of precipitation. * Ground-water recharge is least (0-2 inches per year) in the western and northwestern parts of the State and increases to greater than 6 inches per year in the central and eastern parts of the State. * Water-level measurement frequency is important in estimating recharge. Measurements made less frequently than about once per week resulted in as much as a 48 percent underestimation of recharge compared with estimates based on an hourly measurement frequency. * High-quality, long-term, continuous hydrologic and climatic data are important in estimating recharge rates.

  14. Ground water at Towaoc, Colorado

    USGS Publications Warehouse

    Powell, William J.

    1954-01-01

    At the request of the U.S bureau of Indian Affairs, the Ground Water Branch of the U. S Geological Survey made a reconnaissance of ground-water conditions in part of the Southern Ute Indian Reservation in the vicinity of Towaoc School. The study was requested because the water supply for the school and settlement was inadequate. 

  15. Ground water investigations in Oklahoma

    USGS Publications Warehouse

    Davis, Leon V.

    1955-01-01

    Prior to 1937, ground-water work in Oklahoma consisted of broad scale early-day reconnaissance and a few brief investigations of local areas. The reconnaissance is distinguished by C. N. Gould's "Geology and Water Resources of Oklahoma" (Water-Supply Paper 148, 1905), which covers about half of the present State of Oklahoma. Among the shorter reports are two by Schwennesen for areas near Enid and Oklahoma City, one by Renick for Enid, and one by Thompson on irrigation possibilities near Gage. These reports are now inadequate by modern standards. Cooperative ground-water work in Oklahoma by the United States Geological Survey began in 1937, with the Oklahoma Geological Survey as cooperating agency. With the passage of the new ground-water law by the State Legislature in 1949, the need for more information on available ground waters and the safe yield of the various aquifers became very pressing. Accordingly, the Division of Water Resources of the Oklahoma Planning and Resources Board, to which was delegated the responsibility of administering the Ground-Water Law, entered into a cooperative agreement with the U.S. Geological Survey, providing for an expansion of ground-water investigations. Both cooperators have consistently given full and enthusiastic cooperation, often beyond the requirements of the cooperative program. The first cooperative investigation was an evaluation of ground-water supplies available for irrigation in the Panhandle. In 1937 the Panhandle was still very much in the dust bowl, and it was hoped that irrigation would alleviate the drought. A bulletin on Texas County was published in 1939, and one on Cimarron County in 1943. Ground-water investigations during the World War II were restricted to the demands of Army and Navy installations, and to defense industries. Ground-water investigations since 1945 have included both country-wide and aquifer-type investigations. In Oklahoma it has been the policy for the State cooperator to publish the

  16. Recharge estimation for transient ground water modeling.

    PubMed

    Jyrkama, Mikko I; Sykes, Jon F; Normani, Stefano D

    2002-01-01

    Reliable ground water models require both an accurate physical representation of the system and appropriate boundary conditions. While physical attributes are generally considered static, boundary conditions, such as ground water recharge rates, can be highly variable in both space and time. A practical methodology incorporating the hydrologic model HELP3 in conjunction with a geographic information system was developed to generate a physically based and highly detailed recharge boundary condition for ground water modeling. The approach uses daily precipitation and temperature records in addition to land use/land cover and soils data. The importance of the method in transient ground water modeling is demonstrated by applying it to a MODFLOW modeling study in New Jersey. In addition to improved model calibration, the results from the study clearly indicate the importance of using a physically based and highly detailed recharge boundary condition in ground water quality modeling, where the detailed knowledge of the evolution of the ground water flowpaths is imperative. The simulated water table is within 0.5 m of the observed values using the method, while the water levels can differ by as much as 2 m using uniform recharge conditions. The results also show that the combination of temperature and precipitation plays an important role in the amount and timing of recharge in cooler climates. A sensitivity analysis further reveals that increasing the leaf area index, the evaporative zone depth, or the curve number in the model will result in decreased recharge rates over time, with the curve number having the greatest impact.

  17. Ground water in the Eugene-Springfield area, southern Willamette Valley, Oregon

    USGS Publications Warehouse

    Frank, F.J.

    1973-01-01

    quantity of ground water available annually from this area is far greater than the 23,000 acre-feet pumped for all uses in 1968. This pumpage was about 23 percent of the perennial yield (100,000 acre-ft), and about 77,000 acre-feet of water was left available for additional withdrawal. If annual withdrawals of water were increased to 100,000 acre-feet per year, the levels in the ground-water reservoir would be lowered. Once new equilibriums are established, increased withdrawals could be accommodated without progressive losses in aquifer storage or excessive losses in flow of the larger streams. Ground water from the alluvial deposits of the valley plain is chemically suitable for irrigation and other uses, as is most of the water obtained from perched-water bodies in the sedimentary and volcanic rocks. However, the mineral content of water from the older sedimentary rocks, particularly from deeper producing zones, is greater than the mineral content of water from the alluvial deposits. Locally, some of the water from the older rocks is too saline for most uses. Increased use of ground water may result in certain problems pertaining to waste-disposal practices, local overdraft of aquifers, well interference, and well construction. Present data are adequate to evaluate some of the factors relating to foreseeable problems but allow only tentative conclusions to be drawn about other factors, which include local direction of flow, rate of ground-water movement, and areas of possible ground-water contamination. Additional information obtained through systematic study will be needed to deal with these problems.

  18. Response to memorandum by Rowley and Dixon regarding U.S. Geological Survey report titled "Characterization of Surface-Water Resources in the Great Basin National Park Area and Their Susceptibility to Ground-Water Withdrawals in Adjacent Valleys, White Pine County, Nevada"

    USGS Publications Warehouse

    Prudic, David E.

    2006-01-01

    Applications pending for permanent permits to pump large quantities of ground water in Spring and Snake Valleys adjacent to Great Basin National Park (the Park) prompted the National Park Service to request a study by the U.S. Geological Survey to evaluate the susceptibility of the Park's surface-water resources to pumping. The result of this study was published as U.S. Geological Survey Scientific Investigations Report 2006-5099 'Characterization of Surface-Water Resources in the Great Basin National Park Area and Their Susceptibility to Ground-Water Withdrawals in Adjacent Valleys, White Pine County, Nevada,' by P.E. Elliott, D.A. Beck, and D.E. Prudic. That report identified areas within the Park where surface-water resources are susceptible to ground-water pumping; results from the study showed that three streams and several springs near the eastern edge of the Park were susceptible. However, most of the Park's surface-water resources likely would not be affected by pumping because of either low-permeability rocks or because ground water is sufficiently deep as to not be directly in contact with the streambeds. A memorandum sent by Peter D. Rowley and Gary L. Dixon, Consulting Geologists, to the Southern Nevada Water Authority (SNWA) on June 29, 2006 was critical of the report. The memorandum by Rowley and Dixon was made available to the National Park Service, the U.S. Geological Survey, and the public during the Nevada State Engineer's 'Evidentiary Exchange' process for the recent hearing on applications for ground-water permits by SNWA in Spring Valley adjacent to Great Basin National Park. The U.S. Geological Survey was asked by the National Park Service to assess the validity of the concerns and comments contained in the Rowley and Dixon memorandum. An Administrative Letter Report responding to Rowley and Dixon's concerns and comments was released to the National Park Service on October 30, 2006. The National Park Service subsequently requested that the

  19. Summary appraisals of the Nation's ground-water resources; Lower Colorado region

    USGS Publications Warehouse

    Davidson, E.S.

    1979-01-01

    The potential for greater development of ground water in the southwestern part of the region is constrained by land subsidence, earth cracks, increasing costs of pumping and transportation, and moderate to poor chemical quality of water. More ground water can be developed in the northeastern part of the region, where the major constraint is pumping cost owing to low to moderate well yields and depth to water. Some benefits can be realized everywhere in the region through changes in current use and greater efficiencies of use. Additional supplies may be made available by capture of natural evapotranspiration. Increasing the efficiency of use is possible hydrologically but, in the near term, is more expensive than increasing groundwater development. Decrease of irrigation, change to water-saving methods of irrigation, use of saline water, decrease of per capita public- supply use, and more reuse of water in almost every type of use could help extend the supply and thereby reduce the current rate of ground-water depletion. Financial problems have not yet caused an overall decrease in pumpage, but, locally, operating costs or partial dewatering of the aquifer has eliminated or decreased withdrawal. Current water laws in all States of the region, except Arizona, control or allocate the use of ground water.

  20. Geology and ground-water resources of Uvalde County, Texas

    USGS Publications Warehouse

    Welder, F.A.; Reeves, R.D.

    1964-01-01

    Ground-water withdrawals from the Edwards and associated limestones in Uvalde County probably could be maintained indefinitely at a rate of about 200,000 acre-feet per year, provided that withdrawals north and west of the county were not increased. However, continued withdrawals at this rate-would cause wells in structurally high areas to go dry, and underflow into Medina County would cease. Furthermore, saline water might invade the fresh-water part of the aquifer from the south, and perennial spring flow in the Leona River valley would cease.

  1. Ground-water data for the Beryl-Enterprise area, Escalante Desert, Utah

    USGS Publications Warehouse

    Mower, R.W.

    1981-01-01

    This report contains a compilation of selected ground-water data for the Beryl-Enterprise area, Iron and Washington Counties, Utah. The records of the wells include such information as driller 's logs, yield, drawdown, use, and temperature of the well water. There are also records of water levels in selected wells for the period 1973-79, chemical analyses of ground water, records of selected springs, and a tabulation of ground-water withdrawals for 1937-78. (USGS)

  2. Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, 1901-95, with projections to 2020

    USGS Publications Warehouse

    Kernodle, J.M.

    1998-01-01

    The ground-water-flow model of the Albuquerque Basin (Kernodle, J.M., McAda, D.P., and Thorn, C.R., 1995, Simulation of ground-water flow in the Albuquerque Basin, central New Mexico, with projections to 2020: U.S. Geological Survey Water-Resources Investigations Report 94-4251, 114 p.) was updated to include new information on the hydrogeologic framework (Hawley, J.W., Haase, C.S., and Lozinsky, R.P., 1995, An underground view of the Albuquerque Basin: Proceedings of the 39th Annual New Mexico Water Conference, November 3-4, 1994, p. 37-55). An additional year of ground-water-withdrawal data was appended to the simulation of the historical period and incorporated into the base for future projections to the year 2020. The revised model projects the simulated ground-water levels associated with an aerally enlarged occurrence of the relatively high hydraulic conductivity in the upper part of the Santa Fe Group east and west of the Rio Grande in the Albuquerque area and north to Bernalillo. Although the differences between the two model versions are substantial, the revised model does not contradict any previous conclusions about the effect of City of Albuquerque ground-water withdrawals on flow in the Rio Grande or the net benefits of an effort to conserve ground water. Recent revisions to the hydrogeologic model (Hawley, J.W., Haneberg, W.C., and Whitworth, P.M., in press, Hydrogeologic investigations in the Albuquerque Basin, central New Mexico, 1992-1995: Socorro, New Mexico Bureau of Mines and Mineral Resources Open- File Report 402) of the Albuquerque Basin eventually will require that this model version also be revised and updated.

  3. Ground water and climate change

    USGS Publications Warehouse

    Taylor, Richard G.; Scanlon, Bridget; Döll, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; Konikow, Leonard; Green, Timothy R.; Chen, Jianyao; Taniguchi, Makoto; Bierkens, Marc F.P.; MacDonald, Alan; Fan, Ying; Maxwell, Reed M.; Yechieli, Yossi; Gurdak, Jason J.; Allen, Diana M.; Shamsudduha, Mohammad; Hiscock, Kevin; Yeh, Pat J.-F.; Holman, Ian; Treidel, Holger

    2012-01-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  4. Ground Water and Climate Change

    NASA Technical Reports Server (NTRS)

    Taylor, Richard G.; Scanlon, Bridget; Doell, Petra; Rodell, Matt; van Beek, Rens; Wada, Yoshihide; Longuevergne, Laurent; Leblanc, Marc; Famiglietti, James S.; Edmunds, Mike; Konikow, Leonard; Green, Timothy R.; Chen, Jianyao; Taniguchi, Makoto; Bierkens, Marc F. P.; MacDonald, Alan; Fan, Ying; Maxwell, Reed M.; Yechieli, Yossi; Gurdak, Jason J.; Allen, Diana M.; Shamsudduha, Mohammad; Hiscock, Kevin; Yeh, Pat J. -F; Holman, Ian; Treidel, Holger

    2013-01-01

    As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture and surface water. Here we critically review recent research assessing the impacts of climate on ground water through natural and human-induced processes as well as through groundwater-driven feedbacks on the climate system. Furthermore, we examine the possible opportunities and challenges of using and sustaining groundwater resources in climate adaptation strategies, and highlight the lack of groundwater observations, which, at present, limits our understanding of the dynamic relationship between ground water and climate.

  5. Hydrology and simulation of ground-water flow in Cedar Valley, Iron County, Utah

    USGS Publications Warehouse

    Brooks, Lynette E.; Mason, James L.

    2005-01-01

    sufficient to meet demand. Water levels in many areas are at or close to historic lows. In 2000, withdrawal from wells was estimated to be 36,000 acre-feet per year. About 4,000 acre-feet per year are estimated to discharge to evapotranspiration or as subsurface outflow. Prior to large-scale ground-water development, ground-water discharge by evapotranspiration and discharge to springs was much larger. Ground water along the eastern margin of the valley between Cedar City and Enoch is unsuitable for domestic use because of high dissolved-solids and nitrate concentrations. The predominant ions of Ca and SO4 in this area indicate dissolution of gypsum in the Markagunt Plateau to the east. Data collected during this study were compared to historic data; there is no evidence to indicate deterioration in ground-water quality. The spatial distribution of ground water with high nitrate concentration does not appear to be migrating beyond its previously known extent. No single source can be identified as the cause for elevated nitrate concentrations in ground water. Low nitrogen-15 values north of Cedar City indicate a natural geologic source. Higher nitrogen-15 values toward the center of the basin and associated hydrologic data indicate probable recharge from waste-water effluent. Excess dissolved nitrogen gas and low nitrate concentrations in shallow ground water indicate that denitrification is occurring in some areas. A computer ground-water flow model was developed to simulate flow in the unconsolidated basin fill. The method of determining recharge from irrigation was changed during the calibration process to incorporate more areal and temporal variability. In general, the model accurately simulates water levels and water-level fluctuations and can be considered an adequate tool to help determine the valley-wide effects on water levels of additional ground-water withdrawals and changes in water use. The model was used to simulated water-level changes cau

  6. Summary appraisals of the Nation's ground-water resources; South Atlantic Gulf region

    USGS Publications Warehouse

    Cederstrom, D.J.; Boswell, E.H.; Tarver, G.R.

    1979-01-01

    Ground-water problems generally are not severe. Critical situations are restricted to areas where large quantities of ground water are being withdrawn or where aquifers are contaminated by oil-field or industrial waste. Large withdrawals in coastal areas have caused some saltwater intrusion. In other localities, highly mineralized water may have migrated along fault zones to freshwater aquifers. Many of the present problems can be resolved or ameliorated by redistributing withdrawals or developing alternative water sources.

  7. Ground-water aspects of the lower Henrys Fork region, Idaho

    USGS Publications Warehouse

    Crosthwaite, E.J.; Mundorff, M.J.; Walker, E.H.

    1967-01-01

    The lower Henrys Fork region includes the plains and low benches between Ashton and the junction of Henrys Fork and Snake River in eastern Idaho. The northwestern and western parts of the area are part of the Snake River lava plain. The central part of the area is occupied by alluvial plains of the Snake, Teton, and Falls Rivers, and Henrys Fork. The southeastern part of the area is a bench (Rexburg Bench), chiefly on silicic and basaltic volcanic rocks, which rises gradually to mountain peaks southeast of the area. The basalt, and the sand and gravel under the alluvial plains are good aquifers and yield large amounts of water with small drawdowns. The silicic volcanic rocks and the interbedded ash, pyroclastics, and sedimentary deposits generally yield much less water than the basalt and alluvium. The regional water table slopes southward beneath the basalt and alluvial plains. Seepage from stream channels and irrigated tracts has resulted in an extensive body of ground water perched above the regional water table. The perched water in part moves vertically down to the regional water table and in part laterally to the streams. Ground water beneath the Rexburg Bench moves generally northwestward to join the regional ground-water body beneath the alluvial plain. The regional water table is below the level of the streams in the area and ground water in the main aquifer, therefore is not tributary to the streams. Recharge to the regional water table is estimated to average 725,000 acre-feet annually. Pumping from the regional ground-water reservoir for irrigation or other uses would have no effect on streamflow or surface-water rights within the study area. However, depletion of the underflow would eventually reduce the inflow to American Falls Reservoir unless the depletion was offset by additional recharge. Total withdrawals of ground water for irrigation in 1962 were estimated to be 25,000 acre-feet and caused no significant decline in the water table. In the

  8. Ground-water resources of the Bengasi area, Cyrenaica, United Kingdom of Libya

    USGS Publications Warehouse

    Doyel, William Watson; Maguire, Frank J.

    1964-01-01

    The Benpsi area of Libya, in the northwestern part of the Province of Cyrenaica (Wilayat Barqah), is semiarid, and available ground-water supplies in the area are relatively small. Potable ground water from known sources is reserved for the present and future needs of the city, and no surface-water supplies are available in the area. This investigation to evaluate known, as well as potential, water supplies in the area was undertaken as part of a larger program of ground-water investigations in Libya under the auspices of the U. S. Operations Mission to Libya and the Government of Libya. A ground-water reservoir underlies the Bengasi area, in which the water occurs in solution channels, cavities, and other openings in Miocene limestone. The reservoir is recharged directly by rainfall on the area and by infiltration from ephemeral streams (wadis) rising in Al Jabal al Akhar to the east. In the Baninah and Al Fuwayhit areas the ground-water reservoir yields water of fair quality and in sufficient quantity for the current (1959) needs. of the Bengasi city supply. The test-drilling program in the area south and southeast of Bengasi indicates that water in sufficient quantity for additional public supply probably can be obtained in some localities from wells. The water, however, is moderately to highly mineralized and would require treatment or demineralization before it could be used for additional public supply. Much of the water could be used directly for irrigation, but careful attention would have to be given to cultivation, drainage, and cropping practices. The hazard of saltwater encroachment also exists if large-scale withdrawals are undertaken in the coastal zones.

  9. Hydrogeology and quality of ground water in Orange County, Florida

    USGS Publications Warehouse

    Adamski, James C.; German, Edward R.

    2004-01-01

    on reported measurements or estimates: precipitation was 53 inches per year (in/yr), runoff was 11 in/yr, spring discharge was 2 in/yr, and net lateral subsurface outflow and exported water was 1 in/yr. Evapotranspiration was 39 in/yr, which was calculated as the residual of the water-budget analysis, assuming changes in storage were negligible. Water-quality samples were collected from April 1999 through May 2001 from a total of 26 wells tapping the surficial aquifer system, 1 well tapping the intermediate confining unit, 24 wells tapping the Upper Floridan aquifer, 2 springs issuing from the Upper Floridan aquifer, and 8 wells tapping the Lower Floridan aquifer. These data were supplemented with existing water-quality data collected by the U.S. Geological Survey and St. Johns River Water Management District. Concentrations of total dissolved solids, sulfate, and chloride in samples from the surficial aquifer system generally were low. Concentrations of nitrate were higher in samples from the surficial aquifer system than in samples from the Upper Floridan or Lower Floridan aquifers, probably as a result of agricultural and residential land use. Water type throughout most of the Upper Floridan and Lower Floridan aquifers was calcium or calcium-magnesium bicarbonate, probably as a result of dissolution of the carbonate rocks. Water type in both the surficial and Floridan aquifer systems in eastern Orange County is sodium chloride. Concentrations of total dissolved solids, sulfate, and chloride in the aquifers increase toward eastern Orange County. Data from 16 of 24 wells in eastern Orange County with long-term water-quality records indicated distinct increases in concentrations of chloride over time. The increases probably are related to withdrawal of ground water at the Cocoa well field, causing an upwelling of deeper, more saline water. The most commonly detected trace elements were aluminum, barium, boron, iron, manganese, and strontium. In addition, arse

  10. Geology and ground-water resources of Washington County, Colorado

    USGS Publications Warehouse

    McGovern, Harold E.

    1964-01-01

    to the thickness of saturated material. Development of ground water for irrigation has been generally restricted to the South Platte, Arikaree, and Beaver valleys. There were 134 irrigation wells, 3 industrial wells, and 10 municipal wells in the county in 1959. The annual ground-water pumpage from Washington County is estimated to be 18,000 acre-ft; about 10,000 acre-ft is from the High Plains ground-water province. Although some ground water enters the county as underflow, most of the recharge to ground-water reservoirs is from precipitation on the land surface. Recharge to the Ogallala Formation in the county is assumed to be approximately equal to the natural discharge from the county by underflow because ground-water withdrawals are from storage, and no other significant amount of natural discharge is apparent. Undertow in the Ogallala was calculated to be 83,000 acre-ft per year and the rate of recharge from precipitation to be about 0.95 inch per year. Neither recharge nor discharge was calculated for that part of the county in the South Platte River basin. All ground water in Washington County has a high proportion of carbonate and is classed as hard to very hard. The sodium-adsorption-ratio for all samples analyzed was below the limit recommended for irrigation water. All the water from the Ogallala Formation and most of the water from the Chadron Formation is suitable for domestic use. Some water from the alluvial deposits overlying the Pierre Shale was exceptionally high in calcium, magnesium, and sodium sulfates. Ground water has been heavily developed for irrigation in the South Platte valley and in some parts of the Beaver and Arikaree valleys. Some additional areas, however, could be developed in the latter two valleys. Large quantities of ground water in the Ogallala Formation are available for future development. The quantity of water in storage in the High Plains ground-water province in Washington County is about 6.5 million acre-f

  11. Modeled ground water age distributions

    USGS Publications Warehouse

    Woolfenden, Linda R.; Ginn, Timothy R.

    2009-01-01

    The age of ground water in any given sample is a distributed quantity representing distributed provenance (in space and time) of the water. Conventional analysis of tracers such as unstable isotopes or anthropogenic chemical species gives discrete or binary measures of the presence of water of a given age. Modeled ground water age distributions provide a continuous measure of contributions from different recharge sources to aquifers. A numerical solution of the ground water age equation of Ginn (1999) was tested both on a hypothetical simplified one-dimensional flow system and under real world conditions. Results from these simulations yield the first continuous distributions of ground water age using this model. Complete age distributions as a function of one and two space dimensions were obtained from both numerical experiments. Simulations in the test problem produced mean ages that were consistent with the expected value at the end of the model domain for all dispersivity values tested, although the mean ages for the two highest dispersivity values deviated slightly from the expected value. Mean ages in the dispersionless case also were consistent with the expected mean ages throughout the physical model domain. Simulations under real world conditions for three dispersivity values resulted in decreasing mean age with increasing dispersivity. This likely is a consequence of an edge effect. However, simulations for all three dispersivity values tested were mass balanced and stable demonstrating that the solution of the ground water age equation can provide estimates of water mass density distributions over age under real world conditions.

  12. Ground-water quality, levels, and flow direction near Fort Cobb Reservoir, Caddo County, Oklahoma, 1998-2000

    USGS Publications Warehouse

    Becker, Carol J.

    2001-01-01

    and in the fall due to a seasonal decrease in precipitation, increase in water withdrawals, and increase in evapotranspiration. Ground water near the wastewater spray field moved south-southeast toward Willow Creek along a gradient of about 50 feet per mile. Analysis of ground-water samples suggest that commercial fertilizer is contributing nitrate upgradient of the swine feeding operation and that wastewater from the lagoon is contributing reduced forms of nitrogen, ammonia and nitrite. Additional downgradient wells would be needed to (1) determine if the swine feeding operation is adding excessive amounts of nitrogen to ground water, (2) determine the vertical dimension of wastewater flow, and (3) the extent of wastewater downgradient of the lagoon.

  13. Transboundary impacts on regional ground water modeling in Texas

    USGS Publications Warehouse

    Rainwater, K.; Stovall, J.; Frailey, S.; Urban, L.

    2005-01-01

    Recent legislation required regional grassroots water resources planning across the entire state of Texas. The Texas Water Development Board (TWDB), the state's primary water resource planning agency, divided the state into 16 planning regions. Each planning group developed plans to manage both ground water and surface water sources and to meet future demands of various combinations of domestic, agricultural, municipal, and industrial water consumers. This presentation describes the challenges in developing a ground water model for the Llano Estacado Regional Water Planning Group (LERWPG), whose region includes 21 counties in the Southern High Plains of Texas. While surface water is supplied to several cities in this region, the vast majority of the regional water use comes from the High Plains aquifer system, often locally referred to as the Ogallala Aquifer. Over 95% of the ground water demand is for irrigated agriculture. The LERWPG had to predict the impact of future TWDB-projected water demands, as provided by the TWDB, on the aquifer for the period 2000 to 2050. If detrimental impacts were noted, alternative management strategies must be proposed. While much effort was spent on evaluating the current status of the ground water reserves, an appropriate numerical model of the aquifer system was necessary to demonstrate future impacts of the predicted withdrawals as well as the effects of the alternative strategies. The modeling effort was completed in the summer of 2000. This presentation concentrates on the political, scientific, and nontechnical issues in this planning process that complicated the modeling effort. Uncertainties in data, most significantly in distribution and intensity of recharge and withdrawals, significantly impacted the calibration and predictive modeling efforts. Four predictive scenarios, including baseline projections, recurrence of the drought of record, precipitation enhancement, and reduced irrigation demand, were simulated to

  14. COMPILATION OF GROUND WATER MODELS

    EPA Science Inventory

    The full report presents an overview of currently available computer-based simulation models for ground-water flow, solute and heat transport, and hydrogeochemistry in both porous media and fractured rock. Separate sections address multiphase flow and related chemical species tra...

  15. GROUND WATER TECHNICAL SUPPORT CENTER

    EPA Science Inventory

    EPA's Office of Research and Development operates a Ground Water Technical Support Center (GWTSC). The Center provides support on issues regarding subsurface contamination, contaminant fluxes to other media (e.g., surface water or air), and ecosystem restoration. The GWTSC creat...

  16. GROUND WATER SAMPLING FOR VOCS

    EPA Science Inventory

    Sampling protocol should be dictated by the sampling objective(s). It is important to obtain representative ground water samples, regardless of the sampling objective(s). Low-flow (minimum draw-down) purging and sampling techniques are best in most instances, particularly for VOC...

  17. Simulation of Ground-Water Flow and Effects of Ground-Water Irrigation on Base Flow in the Elkhorn and Loup River Basins, Nebraska

    USGS Publications Warehouse

    Peterson, Steven M.; Stanton, Jennifer S.; Saunders, Amanda T.; Bradley, Jesse R.

    2008-01-01

    Irrigated agriculture is vital to the livelihood of communities in the Elkhorn and Loup River Basins in Nebraska, and ground water is used to irrigate most of the cropland. Concerns about the sustainability of ground-water and surface-water resources have prompted State and regional agencies to evaluate the cumulative effects of ground-water irrigation in this area. To facilitate understanding of the effects of ground-water irrigation, a numerical computer model was developed to simulate ground-water flow and assess the effects of ground-water irrigation (including ground-water withdrawals, hereinafter referred to as pumpage, and enhanced recharge) on stream base flow. The study area covers approximately 30,800 square miles, and includes the Elkhorn River Basin upstream from Norfolk, Nebraska, and the Loup River Basin upstream from Columbus, Nebraska. The water-table aquifer consists of Quaternary-age sands and gravels and Tertiary-age silts, sands, and gravels. The simulation was constructed using one layer with 2-mile by 2-mile cell size. Simulations were constructed to represent the ground-water system before 1940 and from 1940 through 2005, and to simulate hypothetical conditions from 2006 through 2045 or 2055. The first simulation represents steady-state conditions of the system before anthropogenic effects, and then simulates the effects of early surface-water development activities and recharge of water leaking from canals during 1895 to 1940. The first simulation ends at 1940 because before that time, very little pumpage for irrigation occurred, but after that time it became increasingly commonplace. The pre-1940 simulation was calibrated against measured water levels and estimated long-term base flow, and the 1940 through 2005 simulation was calibrated against measured water-level changes and estimated long-term base flow. The calibrated 1940 through 2005 simulation was used as the basis for analyzing hypothetical scenarios to evaluate the effects of

  18. Ground Water and Surface Water in the Haiku Area, East Maui, Hawaii

    USGS Publications Warehouse

    Gingerich, Stephen B.

    1999-01-01

    The Haiku study area lies on the gently sloping eastern flank of the East Maui Volcano (Haleakala) between the drainage basins of Maliko Gulch to the west and Kakipi Gulch to the east. The study area lies on the northwest rift zone of East Maui Volcano, a geologic feature 3 to 5 miles wide marked by surface expressions such as cinder, spatter, and pumice cones. The study area contains two geologic units, the main shield-building stage Honomanu Basalt and the Kula Volcanics. The hydraulic conductivity of the Honomanu Basalt was estimated to be between 1,000 and 3,600 feet per day on the basis of aquifer tests and 3,300 feet per day on the basis of the regional recharge rate and observed ground-water heads. The hydraulic conductivity of the Kula Volcanics is expected to be several orders of magnitude lower. An estimated 191 million gallons per day of rainfall and 22 million gallons per day of fog drip reach the study area and about 98 million gallons per day enters the ground-water system as recharge. Nearly all of the ground water currently withdrawn in the study area is from well 5520-01 in Maliko Gulch, where historic withdrawal rates have averaged about 2.8 million gallons per day. An additional 18 million gallons per day of ground-water withdrawal is proposed. Flow in Waiohiwi Gulch, a tributary to Maliko Gulch, is perennial between about 2,000 ft and 4,000 ft altitude. At lower altitudes in Maliko Gulch, flow is perennial at only a few spots downstream of springs and near the coast. The Kuiaha and Kaupakulua Gulch systems are usually dry from sea level to an altitude of 350 feet and gain water from about 350 feet to about 900 feet altitude. The two main branches of the Kaupakulua Gulch system alternately gain and lose water as high as 2,400 feet altitude. Kakipi Gulch has perennial flow over much of its length but is often dry near the coast below 400 feet altitude. Fresh ground water occurs in two main forms: (1) as perched high-level water held up by

  19. Simulation of Submarine Ground Water Discharge to a Marine Estuary: Biscayne Bay, Florida

    USGS Publications Warehouse

    Langevin, C.D.

    2003-01-01

    Variable density ground water flow models are rarely used to estimate submarine ground water discharge because of limitations in computer speed, data availability, and availability of a simulation tool that can minimize numerical dispersion. This paper presents an application of the SEAWAT code, which is a combined version of MODFLOW and MT3D, to estimate rates of submarine ground water discharge to a coastal marine estuary. Discharge rates were estimated for Biscayne Bay, Florida, for the period from January 1989 to September 1998 using a three-dimensional, variable density ground water flow and transport model. Hydrologic stresses in the 10-layer model include recharge, evapotranspiration, ground water withdrawals from municipal wellfields, interactions with surface water (canals in urban areas and wetlands in the Everglades), boundary fluxes, and submarine ground water discharge to Biscayne Bay. The model was calibrated by matching ground water levels in monitoring wells, baseflow to canals, and the position of the 1995 salt water intrusion line. Results suggest that fresh submarine ground water discharge to Biscayne Bay may have exceeded surface water discharge during the 1989, 1990, and 1991 dry seasons, but the average discharge for the entire simulation period was only ???10% of the surface water discharge to the bay. Results from the model also suggest that tidal canals intercept fresh ground water that might otherwise have discharged directly to Biscayne Bay. This application demonstrates that regional scale variable density models are potentially useful tools for estimating rates of submarine ground water discharge.

  20. Ground-water provinces of Brazil

    USGS Publications Warehouse

    Schneider, Robert

    1962-01-01

    As part of a study of the status of investigations and development of ground water in Brazil, made under the auspices of the United States International Cooperation Administration and with the cooperation of the Government of Brazil, the country was divided into seven ground-water provinces. The identification and delineation of the provinces were based on the regional distribution of the dominant geologic units which are known or inferred to have distinctive water-bearing characteristics. Three of the provinces, covering most of the country, are underlain by Precambrian crystalline rocks. Three others coincide in part with four extensive sedimentary basins--the Parnaiba or Maranhfio basin and the contiguous Sao Francisco basin in the northeast and east, the Amazon basin in the north and northwest, and the Paranfi basin in the south and southwest. In addition, the narrow, discontinuous coastal plain is considered as a province. the occurrence of ground water is discussed briefly, and pertinent data are given on the more important aquifers, together with information on some existing wells. Because of the widespread distribution of crystalline rocks of low permeability, it is difficult in many areas to develop large or even adequate ground-water supplies. In general, satisfactory supplies of water are available in most of the rest of the country. Some problems include the relative deficiency of rainfall in the northeast together with the occurrence, in parts of this region, of mineralized water in the crystalline rocks. Also, there is a potential problem of excessive lowering of water levels and interference among wells in the intensively developed area of the city of Sao Paulo.

  1. Simulation of ground-water flow and movement of the freshwater-saltwater interface in the New Jersey coastal plain

    USGS Publications Warehouse

    Pope, Daryll A.; Gordon, Alison D.

    1999-01-01

    on the historical sea level than on the stresses imposed on the flow system by ground-water withdrawals from the Coastal Plain aquifers from 1896 to 1988. Results of a predictive simulation in which pumpage from existing wells was increased by 30 percent indicate that additional withdrawals from each of the eight confined aquifers in the Coastal Plain would broaden and deepen the existing cones of depression and result in significant drawdowns from the 1988 potentiometric surfaces. Drawdowns of 30 feet were simulated at the center of the cone of depression in the Upper, Middle, and Lower Potomac-Raritan-Magothy aquifers in Camden and Ocean Counties. Simulated drawdowns exceeded 80 feet at the center of the cone of depression in the Wenonah-Mount Laurel and Englishtown aquifers in Monmouth County. Drawdowns of 30 feet were simulated in the lower Kirkwood-Cohansey and confined Kirkwood aquifers in Cape May County. Simulation results showed that the increase in ground-water withdrawals would result in only minimal movement of the freshwater-saltwater interface by 2040, despite large drawdowns.

  2. An application of thermometry to the study of ground water

    USGS Publications Warehouse

    Schneider, Robert

    1962-01-01

    The precise measurement of fluctuations in ground-water temperature, based on monthly readings in shallow glacial-outwash aquifers (up to about 70 feet deep), is useful in the study of ground-water movement and recharge. In addition to the study of natural phenomena in the hydrologic cycle, thermometry may be used as a tool in making detailed studies of (1) the effects of inducing the infiltration of surface water, (2) artificial recharge, (3) the effects of injecting petroleum products or radioactive or other wastes into the ground, and (4) ground-water movement in mines.

  3. Minnesota ground-water quality

    USGS Publications Warehouse

    Albin, D.R.; Bruemmer, L.B.

    1987-01-01

    This report contains summary information on ground-water quality in one of the 50 States, Puerto Rico, the Virgin Islands, or the Trust Territories of the Pacific Islands, Saipan, Guam, and American Samoa. The material is extracted from the manuscript of the 1986 National Water Summary, and with the exception of the illustrations, which will be reproduced in multi-color in the 1986 National Water Summary, the format and content of this report is identical to the State ground-water-quality descriptions to be published in the 1986 National Water Summary. Release of this information before formal publication in the 1986 National Water Summary permits the earliest access by the public.

  4. Texas ground-water quality

    USGS Publications Warehouse

    Strause, Jeffrey L.

    1987-01-01

    This report contains summary information on ground-water quality in one of the 50 States, Puerto Rico, the Virgin Islands, or the Trust Territories of the Pacific Islands, Saipan, Guam, and American Samoa. The material is extracted from the manuscript of the 1986 National Water Summary, and with the exception of the illustrations, which will be reproduced in multi-color in the 1986 National Water Summary, the format and content of this report is identical to the State ground-water-quality descriptions to be published in the 1986 National Water Summary. Release of this information before formal publication in the 1986 National Water Summary permits the earliest access by the public.

  5. Land-subsidence and ground-water storage monitoring in the Tucson Active Management Area, Arizona

    USGS Publications Warehouse

    Pool, Don R.; Winster, Daniel; Cole, K.C.

    2000-01-01

    The Tucson Active Management Area (TAMA) comprises two basins--Tucson Basin and Avra Valley. The TAMA has been directed by Arizona ground-water law to attain an annual balance between groundwater withdrawals and recharge by the year 2025. This balance is defined by the statute as "safe yield." Current ground-water withdrawals exceed recharge, resulting in conditions of ground-water overdraft, which causes removal of water from ground-water storage and subsidence of the land surface. Depletion of storage and associated land subsidence will not be halted until all discharge from the system, both natural and human induced, is balanced by recharge. The amount of the ground-water overdraft has been difficult to estimate until recently because it could not be directly measured. Overdraft has been estimated using indirect water-budget methods that rely on uncertain estimates of recharge. As a result, the status of the ground-water budget could not be known with great certainty. Gravity methods offer a means to directly measure ground-water overdraft through measurement of changes in the gravitational field of the Earth that are caused by changes in the amount of water stored in the subsurface. Changes in vertical position also affect the measured gravity value and thus subsidence also must be monitored. The combination of periodic observations of gravity and vertical positions provide direct measures of changes in stored ground water and land subsidence.

  6. Hanford Site ground-water monitoring for 1994

    SciTech Connect

    Dresel, P.E.; Thorne, P.D.; Luttrell, S.P.

    1995-08-01

    This report presents the results of the Ground-Water Surveillance Project monitoring for calendar year 1994 on the Hanford Site, Washington. Hanford Site operations from 1943 onward produced large quantities of radiologic and chemical waste that have impacted ground-water quality on the Site. Monitoring of water levels and ground-water chemistry is performed to track the extent of contamination and trends in contaminant concentrations. The 1994 monitoring was also designed to identify emerging ground-water quality problems. The information obtained is used to verify compliance with applicable environmental regulations and to evaluate remedial actions. Data from other monitoring and characterization programs were incorporated to provide an integrated assessment of Site ground-water quality. Additional characterization of the Site`s geologic setting and hydrology was performed to support the interpretation of contaminant distributions. Numerical modeling of sitewide ground-water flow also supported the overall project goals. Water-level monitoring was performed to evaluate ground-water flow directions, to track changes in water levels, and to relate such changes to changes in site disposal practices. Water levels over most of the Hanford Site continued to decline between June 1993 and June 1994. These declines are part of the continued response to the cessation of discharge to U Pond and other disposal facilities. The low permeability in this area which enhanced mounding of waste-water discharge has also slowed the response to the reduction of disposal.

  7. Latin hypercube approach to estimate uncertainty in ground water vulnerability.

    PubMed

    Gurdak, Jason J; McCray, John E; Thyne, Geoffrey; Qi, Sharon L

    2007-01-01

    A methodology is proposed to quantify prediction uncertainty associated with ground water vulnerability models that were developed through an approach that coupled multivariate logistic regression with a geographic information system (GIS). This method uses Latin hypercube sampling (LHS) to illustrate the propagation of input error and estimate uncertainty associated with the logistic regression predictions of ground water vulnerability. Central to the proposed method is the assumption that prediction uncertainty in ground water vulnerability models is a function of input error propagation from uncertainty in the estimated logistic regression model coefficients (model error) and the values of explanatory variables represented in the GIS (data error). Input probability distributions that represent both model and data error sources of uncertainty were simultaneously sampled using a Latin hypercube approach with logistic regression calculations of probability of elevated nonpoint source contaminants in ground water. The resulting probability distribution represents the prediction intervals and associated uncertainty of the ground water vulnerability predictions. The method is illustrated through a ground water vulnerability assessment of the High Plains regional aquifer. Results of the LHS simulations reveal significant prediction uncertainties that vary spatially across the regional aquifer. Additionally, the proposed method enables a spatial deconstruction of the prediction uncertainty that can lead to improved prediction of ground water vulnerability. PMID:17470124

  8. Selected ground-water data for Yucca Mountain Region, southern Nevada and eastern California, through December 22

    SciTech Connect

    La Camera, R.J.; Westenburg, C.L.

    1994-08-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site-Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 36 sites, ground-water discharge at 6 sites, ground-water quality at 19 sites, and ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented. Data on ground-water levels, discharges, and withdrawals collected by other agencies (or as part of other programs) are included to further indicate variations through time at selected monitoring locations. Data are included in this report from 1910 through 1992.

  9. Ground Water Atlas of the United States: Segment 1, California, Nevada

    USGS Publications Warehouse

    Planert, Michael; Williams, John S.

    1995-01-01

    California and Nevada compose Segment 1 of the Ground Water Atlas of the United States. Segment 1 is a region of pronounced physiographic and climatic contrasts. From the Cascade Mountains and the Sierra Nevada of northern California, where precipitation is abundant, to the Great Basin in Nevada and the deserts of southern California, which have the most arid environments in the United States, few regions exhibit such a diversity of topography or environment. Since the discovery of gold in the mid-1800's, California has experienced a population, industrial, and agricultural boom unrivaled by that of any other State. Water needs in California are very large, and the State leads the United States in agricultural and municipal water use. The demand for water exceeds the natural water supply in many agricultural and nearly all urban areas. As a result, water is impounded by reservoirs in areas of surplus and transported to areas of scarcity by an extensive network of aqueducts. Unlike California, which has a relative abundance of water, development in Nevada has been limited by a scarcity of recoverable freshwater. The Truckee, the Carson, the Walker, the Humboldt, and the Colorado Rivers are the only perennial streams of significance in the State. The individual basin-fill aquifers, which together compose the largest known ground-water reserves, receive little annual recharge and are easily depleted. Nevada is sparsely populated, except for the Las Vegas, the Reno-Sparks, and the Carson City areas, which rely heavily on imported water for public supplies. Although important to the economy of Nevada, agriculture has not been developed to the same degree as in California due, in large part, to a scarcity of water. Some additional ground-water development might be possible in Nevada through prudent management of the basin-fill aquifers and increased utilization of ground water in the little-developed carbonate-rock aquifers that underlie the eastern one-half of the State

  10. Private Domestic-Well Characteristics and the Distribution of Domestic Withdrawals among Aquifers in the Virginia Coastal Plain

    USGS Publications Warehouse

    Pope, Jason P.; McFarland, E. Randolph; Banks, R. Brent

    2008-01-01

    the area in addition to determination of the geographic distribution of the withdrawals. Because of a lack of comprehensive data on private-well construction and distribution, a sample of private domestic-well records was used to estimate well characteristics and approximate the proportion of wells and withdrawals associated with each aquifer. Construction data on 2,846 private domestic wells were collected from 29 counties and independent cities (localities) having appreciable self-supplied populations and representing private domestic withdrawals of about 31 million gallons per day. Within each locality, geographically stratified random sampling of well records by tax plat characterized details of well construction for the population of domestic wells. Because neither specific location data nor aquifer elevations were available for individual wells, the primary aquifer in which each well is completed was estimated by cross-referencing the screen elevation estimated from the well record with a generalized configuration of hydrogeologic units underlying the locality in which the well is located. For each locality, summarizing the results of this process allowed the determination of the proportion of wells and withdrawals associated with each aquifer. Additional evaluation of spatial data was used to apply the domestic withdrawal rates developed for each aquifer in each locality to a detailed ground-water study of the portion of the Virginia Coastal Plain east of the Chesapeake Bay, which is known as the Eastern Shore Peninsula. Because domestic withdrawal estimates are based on the self-supplied population, the geographic distribution of withdrawals within each of the Eastern Shore counties was estimated by using population data from the 2000 U.S. Census at the resolution of census block groups and further refining the distribution based on road density. The allocation of withdrawals among aquifers was then determined by cross-referencing the spatial distribut

  11. Transboundary impacts on regional ground water modeling in Texas.

    PubMed

    Rainwater, Ken; Stovall, Jeff; Frailey, Scott; Urban, Lloyd

    2005-01-01

    Recent legislation required regional grassroots water resources planning across the entire state of Texas. The Texas Water Development Board (TWDB), the state's primary water resource planning agency, divided the state into 16 planning regions. Each planning group developed plans to manage both ground water and surface water sources and to meet future demands of various combinations of domestic, agricultural, municipal, and industrial water consumers. This presentation describes the challenges in developing a ground water model for the Llano Estacado Regional Water Planning Group (LERWPG), whose region includes 21 counties in the Southern High Plains of Texas. While surface water is supplied to several cities in this region, the vast majority of the regional water use comes from the High Plains aquifer system, often locally referred to as the Ogallala Aquifer. Over 95% of the ground water demand is for irrigated agriculture. The LERWPG had to predict the impact of future TWDB-projected water demands, as provided by the TWDB, on the aquifer for the period 2000 to 2050. If detrimental impacts were noted, alternative management strategies must be proposed. While much effort was spent on evaluating the current status of the ground water reserves, an appropriate numerical model of the aquifer system was necessary to demonstrate future impacts of the predicted withdrawals as well as the effects of the alternative strategies. The modeling effort was completed in the summer of 2000. This presentation concentrates on the political, scientific, and nontechnical issues in this planning process that complicated the modeling effort. Uncertainties in data, most significantly in distribution and intensity of recharge and withdrawals, significantly impacted the calibration and predictive modeling efforts. Four predictive scenarios, including baseline projections, recurrence of the drought of record, precipitation enhancement, and reduced irrigation demand, were simulated to

  12. Analysis of ground-water data for selected wells near Holloman Air Force Base, New Mexico, 1950-95

    USGS Publications Warehouse

    Huff, G.F.

    1996-01-01

    Ground-water-level, ground-water-withdrawal, and ground- water-quality data were evaluated for trends. Holloman Air Force Base is located in the west-central part of Otero County, New Mexico. Ground-water-data analyses include assembly and inspection of U.S. Geological Survey and Holloman Air Force Base data, including ground-water-level data for public-supply and observation wells and withdrawal and water-quality data for public-supply wells in the area. Well Douglas 4 shows a statistically significant decreasing trend in water levels for 1972-86 and a statistically significant increasing trend in water levels for 1986-90. Water levels in wells San Andres 5 and San Andres 6 show statistically significant decreasing trends for 1972-93 and 1981-89, respectively. A mixture of statistically significant increasing trends, statistically significant decreasing trends, and lack of statistically significant trends over periods ranging from the early 1970's to the early 1990's are indicated for the Boles wells and wells near the Boles wells. Well Boles 5 shows a statistically significant increasing trend in water levels for 1981-90. Well Boles 5 and well 17S.09E.25.343 show no statistically significant trends in water levels for 1990-93 and 1988-93, respectively. For 1986-93, well Frenchy 1 shows a statistically significant decreasing trend in water levels. Ground-water withdrawal from the San Andres and Douglas wells regularly exceeded estimated ground-water recharge from San Andres Canyon for 1963-87. For 1951-57 and 1960-86, ground-water withdrawal from the Boles wells regularly exceeded total estimated ground-water recharge from Mule, Arrow, and Lead Canyons. Ground-water withdrawal from the San Andres and Douglas wells and from the Boles wells nearly equaled estimated ground- water recharge for 1989-93 and 1986-93, respectively. For 1987- 93, ground-water withdrawal from the Escondido well regularly exceeded estimated ground-water recharge from Escondido Canyon, and

  13. Recovery of Ground-Water Levels From 1988 to 2003 and Analysis of Potential Water-Supply Management Options in Critical Area 1, East-Central New Jersey

    USGS Publications Warehouse

    Spitz, Frederick J.; Watt, Martha K.; dePaul, Vincent T.

    2008-01-01

    Water levels in four confined aquifers in the New Jersey Coastal Plain within Water Supply Critical Area 1 have recovered as a result of reductions in ground-water withdrawals initiated by the State in the late 1980s. The aquifers are the Wenonah-Mount Laurel, the Upper and Middle Potomac-Raritan-Magothy, and Englishtown aquifer system. Because of increased water demand due to increased development in Monmouth, Ocean, and Middlesex Counties, five base and nine alternate management models were designed for the four aquifers to evaluate the effects resulting from potential reallocation of part of the Critical Area 1 reductions in withdrawals. The change in withdrawals and associated water-level changes in the aquifers for 1988-2003 are discussed. Generally, withdrawals decreased 25 to 30 Mgal/d (million gallons per day), and water levels increased 0 to 80 ft (feet). The Regional Aquifer-System Analysis (RASA) ground-water-flow model of the New Jersey Coastal Plain developed by the U.S. Geological Survey was used to simulate ground-water flow and optimize withdrawals using the Ground-Water Management Process (GWM) for MODFLOW. Results of the model were used to evaluate the effects of several possible water-supply management options in order to provide the information to water managers. The optimization method, which provides a means to set constraints that support mandated hydrologic conditions, then determine the maximum withdrawals that meet the constraints, is a more cost-effective approach than simulating a range of withdrawals to determine the effects on the aquifer system. The optimization method is particularly beneficial for a regional-scale study of this kind because of the large number of wells to be evaluated. Before the model was run, a buffer analysis was done to define an area with no additional withdrawals that minimizes changes in simulated streamflow in aquifer outcrop areas and simulated movement of ground water toward the wells from areas of

  14. Geohydrology and simulated ground-water flow, Plymouth-Carver Aquifer, southeastern Massachusetts

    USGS Publications Warehouse

    Hansen, Bruce P.; Lapham, Wayne W.

    1992-01-01

    The Plymouth-Carver aquifer underlies an area of 140 square miles and is the second largest aquifer in areal extent in Massachusetts. It is composed primarily of saturated glacial sand and gravel. The water-table and bedrock surface were mapped and used to determine saturated thickness of the aquifer, which ranged from less than 20 feet to greater than 200 feet. Ground water is present mainly under unconfined conditions, except in a few local areas such as beneath Plymouth Harbor. Recharge to the aquifer is derived almost entirely from precipitation and averages about 1.15 million gallons per day per square mile. Water discharges from the aquifer by pumping, evapotranspiration, direct evaporation from the water table, and seepage to streams, ponds, wetlands, bogs, and the ocean. In 1985, water use was about 59.6 million gallons per day, of which 82 percent was used for cranberry production. The Plymouth-Carver aquifer was simulated by a three-dimensional, finite difference ground-water-flow model. Most model boundaries represent the natural hydrologic boundaries of the aquifer. The model simulates aquifer recharge, withdrawals by pumped wells, leakage through streambeds, and discharge to the ocean. The model was calibrated for steady-state and transient conditions. Model results were compared with measured values of hydraulic head and ground-water discharge. Results of simulations indicate that the modeled ground-water system closely simulates actual aquifer conditions. Four hypothetical ground-water development alternatives were simulated to demonstrate the use of the model and to examine the effects on the ground-water system. Simulation of a 2-year period of no recharge and average pumping rates that occurred from 1980-85 resulted in water-level declines exceeding 5 feet throughout most of the aquifer and a decrease of 54 percent in average ground-water discharge to streams. In a second simulation, four wells in the northern part of the area were pumped at 10

  15. Ground water recharge and flow characterization using multiple isotopes.

    PubMed

    Chowdhury, Ali H; Uliana, Matthew; Wade, Shirley

    2008-01-01

    Stable isotopes of delta(18)O, delta(2)H, and (13)C, radiogenic isotopes of (14)C and (3)H, and ground water chemical compositions were used to distinguish ground water, recharge areas, and possible recharge processes in an arid zone, fault-bounded alluvial aquifer. Recharge mainly occurs through exposed stream channel beds as opposed to subsurface inflow along mountain fronts. This recharge distribution pattern may also occur in other fault-bounded aquifers, with important implications for conceptualization of ground water flow systems, development of ground water models, and ground water resource management. Ground water along the mountain front near the basin margins contains low delta(18)O, (14)C (percent modern carbon [pmC]), and (3)H (tritium units [TU]), suggesting older recharge. In addition, water levels lie at greater depths, and basin-bounding faults that locally act as a flow barrier may further reduce subsurface inflow into the aquifer along the mountain front. Chemical differences in ground water composition, attributed to varying aquifer mineralogy and recharge processes, further discriminate the basin-margin and the basin-center water. Direct recharge through the indurated sandstones and mudstones in the basin center is minimal. Modern recharge in the aquifer is mainly through the broad, exposed stream channel beds containing coarse sand and gravel where ground water contains higher delta(18)O, (14)C (pmC), and (3)H (TU). Spatial differences in delta(18)O, (14)C (pmC), and (3)H (TU) and occurrences of extensive mudstones in the basin center suggest sluggish ground water movement, including local compartmentalization of the flow system.

  16. Hydrogeology and ground-water/surface water interactions in the Des Moines River valley, southwestern Minnesota, 1997-2001

    USGS Publications Warehouse

    Cowdery, Timothy K.

    2005-01-01

    Long-term withdrawals of water for public supplies may cause a net decrease in ground-water discharge to surface water. Water that does not evaporate, or that is not exported, is discharged to the Des Moines River but with changed water quality. Because ground-water and surface-water qualities in the study area are similar, the ground-water discharge probably has little effect on river water quality.

  17. Proposed expansion of the City of Albuquerque/U.S. Geological Survey ground-water-level monitoring network for the middle Rio Grande Basin, New Mexico

    USGS Publications Warehouse

    Bexfield, L.M.

    1998-01-01

    The Middle Rio Grande Basin in central New Mexico, extending from Cochiti Lake on the north to San Acacia on the south, covers an area of about 3,060 square miles. Ground-water withdrawals in the basin are concentrated in and around the city of Albuquerque. Because of rapid increases in population and associated ground-water pumpage, a network of wells was established cooperatively by the City of and the U.S. Geological Survey between April 1982 and September 1983 to monitor changes in ground-water levels throughout the basin. Expansion of this network has been identified as an essential element in plans to study the relation between surface water and ground water in the basin. An inventory of existing wells in the Albuquerque metropolitan area has brought together information on about 400 wells that either are being monitored for water levels or would be good candidates for monitoring. About 115 wells or well sites are proposed as additions to the current 128-well ground-water-level monitoring network for the Middle Rio Grande Basin. Despite the extensive network that would be created by the addition of the proposed existing wells, however, certain parts of the Albuquerque metropolitan area would remain without adequate coverage areally and/or with depth in the Santa Fe Group aquifer until the installation of the proposed new monitoring wells.

  18. Hydrogeology, ground-water use, and ground-water levels in the Mill Creek Valley near Evendale, Ohio

    USGS Publications Warehouse

    Schalk, Charles; Schumann, Thomas

    2002-01-01

    Withdrawals of ground water in the central Mill Creek Valley near Evendale, Ohio, caused water-level declines of more than 100 feet by the 1950s. Since the 1950s, management practices have changed to reduce the withdrawals of ground water, and recovery of water levels in long-term monitoring wells in the valley has been documented. Changing conditions such as these prompted a survey of water use, streamflow conditions, and water levels in several aquifers in the central Mill Creek Valley, Hamilton and Butler Counties, Ohio. Geohydrologic information, water use, and water levels were compiled from historical records and collected during the regional survey. Data collected during the survey are presented in terms of updated geohydrologic information, water use in the study area, water levels in the aquifers, and interactions between ground water and surface water. Some of the data are concentrated at former Air Force Plant 36 (AFP36), which is collocated with the General Electric Aircraft Engines (GEAE) plant, and these data are used to describe geohydrology and water levels on a more local scale at and near the plant. A comparison of past and current ground-water use and levels indicates that the demand for ground water is decreasing and water levels are rising. Before 1955, most of the major industrial ground-water users had their own wells, ground water was mined from a confined surficial (lower) aquifer, and water levels were more than 100 feet below their predevelopment level. Since 1955, however, these users have been purchasing their water from the city of Cincinnati or a private water purveyor. The cities of Reading and Lockland, both producers of municipal ground-water supplies in the area, shut down their well fields within their city limits. Because the demand for ground-water supplies in the valley has lessened greatly since the 1950s, withdrawals have decreased, and, consequently, water levels in the lower aquifer are 65 to 105 feet higher than they were

  19. Hydrogeology and Ground-Water Quality, Chippewa Township, Isabella County, Michigan, 2002-05

    USGS Publications Warehouse

    Westjohn, David B.; Hoard, Chris J.

    2006-01-01

    The ground-water resource potential of Chippewa Township, Isabella County, Mich. was characterized on the basis of existing hydrogeologic data, water-level records, analyses of water samples, and interpretation of geophysical survey data. Eight ground-water samples were collected and analyzed for major ions, nutrients, and trace-metal composition. In addition, 10 direct current-resistivity soundings were collected throughout Chippewa and Coe Townships to identify potential freshwater in the aquifer system. The aquifer system includes complexly interbedded glaciofluvial, glaciolacustrine, and basal-lodgment tills, which overlie Jurassic or Pennsylvanian sedimentary rocks. In parts of the township, freshwater is present in all geologic units, but in most areas saline water is encountered near the base of Pleistocene glacial deposits and in the Jurassic or Pennsylvanian bedrock. A near-surface sheet of relatively dense basal-lodgment till likely prevents, or substantially retards, significant direct recharge of ground water to glacial and bedrock aquifers in Chippewa and adjacent townships. Glacial sands and gravels form the principal aquifer for domestic wells (97.5 percent of wells in the township). The single community water supply in the township has wells screened in glacial deposits near the base of the glacial drift. Increased withdrawals of ground water in response to increasing demand has led to a slight decline in water quality from this supply. This water-quality decline is related primarily to an increase of dissolved sulfate, which is probably a function of well depth and dissolution of gypsum, a common mineral constituent in the Jurassic 'red beds,' which form the uppermost bedrock unit throughout most of the township. One explanation for the increase in sulfate is upconing of saline water from bedrock sources, which may contain saline water.

  20. ADVANCES IN GROUND WATER SAMPLING PROCEDURES

    EPA Science Inventory

    Obtaining representative ground water samples is important for site assessment and remedial performance monitoring objectives. Issues which must be considered prior to initiating a ground-water monitoring program include defining monitoring goals and objectives, sampling point...

  1. Estimated withdrawals and use of freshwater in New Hampshire, 1990

    USGS Publications Warehouse

    Medalie, Laura; Horn, M.A.

    1994-01-01

    Estimated freshwater withdrawals during 1990 in New Hampshire totaled about 422 million gallons per day from ground-water and surface-water sources. The largest withdrawals were for thermoelectric-power generation (60 percent), public supply (23 percent), and industrial use (9 percent). Most withdrawals, 358 million gallons per day, were made from surface- water sources, as compared to 63.7 million gallons per day from ground-water sources. The largest with- drawals were in the Merrimack river basin (322 million gallons per day). An additional 46,000 million gallons per day was used instream for hydroelectric-power generation, primarily in the Upper Androscoggin and Upper Connecticut River subbasins. Other information describing water-use patterns is shown in tables, bar graphs, pie charts, maps, and accompanying text. The data are aggregated by river basin (hydrologic cataloging unit), and all values are reported in million gallons per day.

  2. Ground-water aspects of the lower Henrys Fork region, eastern Idaho

    USGS Publications Warehouse

    Crosthwaite, E.G.; Mundorff, Maurice John; Walker, Eugene H.

    1970-01-01

    -water rights within the study area. However, depletion of the underflow would eventually reduce the inflow to American Falls Reservoir, unless the depletion was offset by additional recharge. Total withdrawals of ground water for irrigation in 1962, principally in the Rexburg Bench, were estimated to be 25,000 acre-feet. About 10,000 acre-feet was withdrawn for domestic, municipal, and stock supplies. These withdrawals caused no significant decline in the water table. In the Ashton area, surface-water irrigation has caused water to be perched in basalt above the silicic volcanic rocks, and much of' this perched water contributes to streamflow. Some ground water can be pumped from the basalt for irrigation and other uses. If ground water were pumped for irrigation, the flow of Henrys Fork would be decreased by the amount of pumped water consumed by crops. Water pumped for nonconsumptive use would have little effect on streamflow. Ground-water prospects for irrigation in the Falls River area are not encouraging.

  3. Effects of recharge, Upper Floridan aquifer heads, and time scale on simulated ground-water exchange with Lake Starr, a seepage lake in central Florida

    USGS Publications Warehouse

    Swancar, Amy; Lee, Terrie Mackin

    2003-01-01

    Lake Starr and other lakes in the mantled karst terrain of Florida's Central Lake District are surrounded by a conductive surficial aquifer system that receives highly variable recharge from rainfall. In addition, downward leakage from these lakes varies as heads in the underlying Upper Floridan aquifer change seasonally and with pumpage. A saturated three-dimensional finite-difference ground-water flow model was used to simulate the effects of recharge, Upper Floridan aquifer heads, and model time scale on ground-water exchange with Lake Starr. The lake was simulated as an active part of the model using high hydraulic conductivity cells. Simulated ground-water flow was compared to net ground-water flow estimated from a rigorously derived water budget for the 2-year period August 1996-July 1998. Calibrating saturated ground-water flow models with monthly stress periods to a monthly lake water budget will result in underpredicting gross inflow to, and leakage from, ridge lakes in Florida. Underprediction of ground-water inflow occurs because recharge stresses and ground-water flow responses during rainy periods are averaged over too long a time period using monthly stress periods. When inflow is underestimated during calibration, leakage also is underestimated because inflow and leakage are correlated if lake stage is maintained over the long term. Underpredicted leakage reduces the implied effect of ground-water withdrawals from the Upper Floridan aquifer on the lake. Calibrating the weekly simulation required accounting for transient responses in the water table near the lake that generated the greater range of net ground-water flow values seen in the weekly water budget. Calibrating to the weekly lake water budget also required increasing the value of annual recharge in the nearshore region well above the initial estimate of 35 percent of the rainfall, and increasing the hydraulic conductivity of the deposits around and beneath the lake. To simulate the total

  4. Ground-Water Quality Data in the Coastal Los Angeles Basin Study Unit, 2006: Results from the California GAMA Program

    USGS Publications Warehouse

    Mathany, Timothy M.; Land, Michael; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 860 square-mile Coastal Los Angeles Basin study unit (CLAB) was investigated from June to November of 2006 as part of the Statewide Basin Assessment Project of the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide Basin Assessment was developed in response to the Ground-Water Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The Coastal Los Angeles Basin study was designed to provide a spatially unbiased assessment of raw ground-water quality within CLAB, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 69 wells in Los Angeles and Orange Counties. Fifty-five of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study area (?grid wells?). Fourteen additional wells were selected to evaluate changes in ground-water chemistry or to gain a greater understanding of the ground-water quality within a specific portion of the Coastal Los Angeles Basin study unit ('understanding wells'). Ground-water samples were analyzed for: a large number of synthetic organic constituents [volatile organic compounds (VOCs), gasoline oxygenates and their degradates, pesticides, polar pesticides, and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicators]; constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), 1,4-dioxane, and 1,2,3-trichloropropane (1,2,3-TCP)]; inorganic constituents that can occur naturally [nutrients, major and minor ions, and trace elements]; radioactive constituents [gross-alpha and gross-beta radiation, radium isotopes, and radon-222]; and microbial indicators. Naturally occurring isotopes [stable isotopic ratios of hydrogen and oxygen, and activities of tritium and carbon-14

  5. Ground-Water Quality Data in the Santa Clara River Valley Study Unit, 2007: Results from the California GAMA Program

    USGS Publications Warehouse

    Montrella, Joseph; Belitz, Kenneth

    2009-01-01

    and age of the sampled ground water. Quality-control samples (blanks or replicates, or samples for matrix spikes) were collected from approximately 26 percent of the wells, and the analyses of these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control results showed that the quality of the environmental data was good, with low bias and low variability, and as a result, less than 0.1 percent of the analytes detected in ground-water samples were censored. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, and (or) blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is delivered (or, supplied) to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with regulatory and non-regulatory thresholds established by the U.S. Environmental Protection Agency (USEPA) and the California Department of Public Health (CDPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CDPH. Most constituents that were detected in ground-water samples were reported at concentrations below their established health-based thresholds. VOCs, pesticides and pesticide degradates, and potential wastewater-indicator compounds were detected in about 33 percent or less of the 42 SCRV grid wells. Concentrations of all detected organic constituents were below established health-based thresholds. Perchlorate was detected in approximately 12 percent of the SCRV grid wells; all concentrations reported were below the NL-CA threshold. Additional constituents, including major ions, trace elements, and nutrients were collected at 26 wells (16 grid wells and 10 understanding wells) of the 53 wells sampled f

  6. Ground-water hydrology of the Willamette basin, Oregon

    USGS Publications Warehouse

    Conlon, Terrence D.; Wozniak, Karl C.; Woodcock, Douglas; Herrera, Nora B.; Fisher, Bruce J.; Morgan, David S.; Lee, Karl K.; Hinkle, Stephen R.

    2005-01-01

    productive water-bearing zones. A basement confining unit of older marine and volcanic rocks of low permeability underlies the basin and occurs at land surface in the Coast Range and western part of the Cascade Range. Most recharge in the basin is from infiltration of precipitation, and the spatial distribution of recharge mimics the distribution of precipitation, which increases with elevation. Basinwide annual mean recharge is estimated to be 22 inches. Rain and snowmelt easily recharge into the permeable High Cascade unit and discharge within the High Cascade area. Most recharge in the Coast Range and western part of the Cascade Range follows short flowpaths through the upper part of the low permeability material and discharges to streams within the mountains. Consequently, recharge in the Coast and Ranges is not available as lateral ground-water flow into the lowland, where most ground-water use occurs. Within the lowland, annual mean recharge is 16 inches and most recharge occurs from November to April, when rainfall is large and evapotranspiration is small. From May to October recharge is negligible because precipitation is small and evapotranspiration is large. Discharge of ground water is mainly to streams. Ground-water discharge is a relatively large component of flow in streams that drain the High Cascade unit and parts of the Portland Basin where permeable units are at the surface. In streams that do not head in the High Cascade area, streamflow is generally dominated by runoff of precipitation. Ground-water in the permeable units in the lowland discharges to the major streams where there is a good hydraulic connection between aquifers and streams. Ground-water discharge to smaller streams, which flow on the less permeable Willamette silt unit, is small and mostly from the Willamette silt unit. Most ground-water withdrawals occur within the lowland. Irrigation is the largest use of ground water, accounting for 240,000 acre feet of withdrawals, or 81 p

  7. U.S. Geological Survey ground-water studies in Texas

    USGS Publications Warehouse

    Land, L.F.

    1988-01-01

    Ground-water resources supply almost 60 percent of the freshwater used in Texas, excluding withdrawals for thermoelectric-power generation (less than 3 percent). About 73 percent of the ground water withdrawn is used for irrigation, about 17 percent for public supply, and about 7 percent for industrial, rural domestic, and livestock uses. About 8 million people, or 48 percent of the population of Texas, depend on ground water as a public or rural domestic supply. The dependence on ground water is greatest in the arid northwestern part of the State, where most of the water is used for irrigation. This area contains 70 percent of all irrigated land in Texas, and uses about 85 percent of the total ground water withdrawn for irrigation.

  8. Simulated changes in ground-water levels related to proposed development of Federal coal leases, San Juan Basin New Mexico

    USGS Publications Warehouse

    Frenzel, P.F.

    1983-01-01

    The effects of coal-related ground-water withdrawals on potentiometric surfaces of aquifers in the San Juan Basin, New Mexico, were estimated. A previously published steady-state finite-difference digital model was converted to a transient-state model by changing boundary conditions and adding storage coefficients. No calibration of the transient-state model was attempted. Predicted drawdowns with a minimum amount of coal development combined with other kinds of development were as great as 2,000 feet. As much as 300 feet of additional drawdown were simulated for the maximum amount of coal development. Drawdowns near pumping wells are not predicted. (USGS)

  9. Sustainability of ground-water resources

    USGS Publications Warehouse

    Alley, William M.; Reilly, Thomas E.; Franke, O. Lehn

    1999-01-01

    The pumpage of fresh ground water in the United States in 1995 was estimated to be approximately 77 billion gallons per day (Solley and others, 1998), which is about 8 percent of the estimated 1 trillion gallons per day of natural recharge to the Nation's ground-water systems (Nace, 1960). From an overall national perspective, the ground-water resource appears ample. Locally, however, the availability of ground water varies widely. Moreover, only a part of the ground water stored in the subsurface can be recovered by wells in an economic manner and without adverse consequences.

  10. Ground-Water Data for Georgia, 1988

    USGS Publications Warehouse

    Joiner, Charles N.; Peck, Michael F.; Reynolds, Mark S.; Stayton, Welby L.

    1989-01-01

    Continuous water-level records from 144 wells and water-level measurements from an additional 617 wells in Georgia during 1988 provide the basic data for this report. Daily mean water-level hydrographs for selected wells illustrate the effects that changes ln recharge and discharge have had on the ground-water reservoirs in the State during 1988. Monthly mean water levels are shown for the 10-year period 1979-88. Maps showing the potentiometric surface of the Upper Floridan aquifer for Hay 1988 and the Claiborne and Clayton aquifers for October 1988 also are presented. Annual mean water levels in Georgia generally were below those measured in 1987; water levels ranged from 6.9 feet higher to 7.3 feet lower. Record-low water levels were measured during the last half of 1988 in 18 wells tapping the crystalline rock aquifer, the Cretaceous rock aquifer system, the Midville aquifer system, and the Clayton, Upper Floridan, and upper Brunswick aquifers. These record lows were from 0.1 to 1.4 feet lower than the previous record lows. A prolonged drought resulted in decreased recharge to the aquifers and increased ground-water pumping, which caused water levels to decline. Water-quality samples collected periodically throughout Georgia are analyzed as part of areal and regional ground-water studies. Maps showing chloride concentrations in the Upper Floridan aquifer in October 1988 in coastal Georgia and in the Savannah and Brunswick areas are presented. Periodic monitoring of water quality in the Savannah and Brunswick areas indicates that chloride concentrations in the Upper Floridan generally have remained stable.

  11. Ground water in Creek County, Oklahoma

    USGS Publications Warehouse

    Cady, Richard Carlysle

    1937-01-01

    Creek County has been designated as a problem area by the Land Use Planning Section of the Resettlement Administration. Some of the earliest oil fields to brought into production were situated in and near this county, and new fields have been opened from time to time during the ensuing years. The production of the newer fields, however, has not kept pace with the exhaustion of the older fields, and the county now presents an excellent picture of the problems involved in adjusting a population to lands that are nearly depleted of their mineral wealth. Values of land have been greatly depressed; tax collection is far in arrears; tenancy is widespread; and in addition more people will apparently be forced to depend on the income from agriculture than the land seems capable of supporting. The county as a whole is at best indifferently suitable for general farming. The Land Use planning Section proposes to study the present and seemingly immanent maladjustments of population to the resources of the land, and make recommendations for their correction. The writer was detailed to the Land Use Planning Section of Region VIII for the purposes of making studies of ground water problems in the region. In Creek County two investigations were made. In September, 1936, the writer spent about ten days investigating the availability of ground water for the irrigation of garden crops during drouths. If it proved feasible to do this generally throughout the county, the Land Use Planning Section might be able to encourage this practice. The second investigation made by the writer was in regard to the extent to which ground water supplies have been damaged by oil well brines. He was in county for four days late in January 1937, and again in March, 1937. During part of the second field trip he was accompanied by R.M. Dixon, sanitary engineer of the Water Utilization Unit of the Resettlement Administration. (available as photostat copy only)

  12. Ground Water Atlas of the United States: Segment 8, Montana, North Dakota, South Dakota, Wyoming

    USGS Publications Warehouse

    Whitehead, R.L.

    1996-01-01

    completed in semiconsolidated- and consolidated-rock aquifers, chiefly sandstone and limestone. Some wells withdraw water from volcanic rocks, igneous and metamorphic rocks, or fractured fine-grained sedimentary rocks, such as shale; however, wells completed in these types of rocks generally yield only small volumes of water. Most wells in the four-State area of Segment 8 are on privately owned land (fig. 2). Agriculture, primarily irrigation, is one of the largest uses of ground water. The irrigation generally is on lowlands close to streams (fig. 3). Lowlands within a few miles of major streams usually are irrigated with surface water that is diverted by gravity flow from the main stream or a reservoir and transported through a canal system. Surface water also is pumped to irrigate land that gravity systems cannot supply. In addition, ground water is pumped from large-capacity wells to supplement surface water during times of drought or during seasons of the year when surface water is in short supply. Ground water is the only source of water for irrigation in much of the segment. The thickness and permeability of aquifers in the area of Segment 8 vary considerably, as do yields of wells completed in the aquifers. Ground-water levels and artesian pressures (hydraulic head) have declined significantly in some places as a result of excessive withdrawals by wells. State governments have taken steps to control the declines by enacting programs that either limit the number of additional wells that can be completed in a particular aquifer or prevent further ground-water development altogether. The demand for water is directly related to the distribution of people. In 1990, Montana had a population of 799,065; North Dakota, 638,800; South Dakota, 696,004; and Wyoming, 453,588. The more densely populated areas are on lowlands near major streams. Many of the mountain, desert, and upland areas lack major population centers, particularly in Montana and Wyoming, where use

  13. Ground-water discharge determined from measurements of evapotranspiration, other available hydrologic components, and shallow water-level changes, Oasis Valley, Nye County, Nevada

    SciTech Connect

    Reiner,S.R.; Laczniak, R.J.; DeMeo, G.A.; Smith, J.LaRue; Elliott, P.E.; Nylund, W.E.; Fridrich, C.J.

    2002-01-29

    component of 0.5 foot, is estimated to be about 6,000 acre-feet. Annual subsurface outflow from Oasis Valley into the Amargosa Desert is estimated to be between 30 and 130 acre-feet. Estimates of total annual ground-water withdrawal from Oasis Valley by municipal and non-municipal users in 1996 and 1999 are 440 acre-feet and 210 acre-feet, respectively. Based on these values, natural annual ground-water discharge from Oasis Valley is about 6,100 acre-feet. Total annual discharge was 6,500 acre-feet in 1996 and 6,300 acre-feet in 1999. This quantity of natural ground-water discharge from Oasis Valley exceeds the previous estimate made in 1962 by a factor of about 2.5. Water levels were measured in Oasis Valley to gain additional insight into the ET process. In shallow wells, water levels showed annual fluctuations as large as 7 feet and daily fluctuations as large as 0.2 foot. These fluctuations may be attributed to water loss associated with evapotranspiration. In shallow wells affected by E T, annual minimum depths to water generally occurred in winter or early spring shortly after daily ET reached minimum rates. Annual maximum depths to water generally occurred in late summer or fall shortly after daily ET reached maximum rates. The magnitude of daily water-level fluctuations generally increased as ET increased and decreased as depth to water increased.

  14. Ground-water discharge determined from measurements of evapotranspiration, other available hydrologic components, and shallow water-level changes, Oasis Valley, Nye County, Nevada

    USGS Publications Warehouse

    Reiner, S.R.; Laczniak, R.J.; DeMeo, G.A.; Smith, Jody L.; Elliott, P.E.; Nylund, W.E.; Fridrich, C.J.

    2002-01-01

    component of 0.5 foot, is estimated to be about 6,000 acre-feet. Annual subsurface outflow from Oasis Valley into the Amargosa Desert is estimated to be between 30 and 130 acre-feet. Estimates of total annual ground-water withdrawal from Oasis Valley by municipal and non-municipal users in 1996 and 1999 are 440 acre-feet and 210 acre-feet, respectively. Based on these values, natural annual ground-water discharge from Oasis Valley is about 6,100 acre-feet. Total annual discharge was 6,500 acre-ft in 1996 and 6,300 acre-ft in 1999. This quantity of natural ground-water discharge from Oasis Valley exceeds the previous estimate made in 1962 by a factor of about 2.5. Water levels were measured in Oasis Valley to gain additional insight into the ET process. In shallow wells, water levels showed annual fluctuations as large as 7 feet and daily fluctuations as large as 0.2 foot. These fluctuations may be attributed to water loss associated with evapotranspiration. In shallow wells affected by ET, annual minimum depths to water generally occurred in winter or early spring shortly after daily ET reached minimum rates. Annual maximum depths to water generally occurred in late summer or fall shortly after daily ET reached maximum rates. The magnitude of daily water-level fluctuations generally increased as ET increased and decreased as depth to water increased.

  15. Ground-Water Quality Data in the Coachella Valley Study Unit, 2007: Results from the California GAMA Program

    USGS Publications Warehouse

    Goldrath, Dara A.; Wright, Michael T.; Belitz, Kenneth

    2009-01-01

    Ground-water quality in the approximately 820 square-mile Coachella Valley Study Unit (COA) was investigated during February and March 2007 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of raw ground water used for public-water supplies within the Coachella Valley, and to facilitate statistically consistent comparisons of ground-water quality throughout California. Samples were collected from 35 wells in Riverside County. Nineteen of the wells were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Sixteen additional wells were sampled to evaluate changes in water chemistry along selected ground-water flow paths, examine land use effects on ground-water quality, and to collect water-quality data in areas where little exists. These wells were referred to as 'understanding wells'. The ground-water samples were analyzed for a large number of organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (uranium, tritium, carbon-14, and stable isotopes of hydrogen, oxygen, and boron), and dissolved noble gases (the last in collaboration with Lawrence Livermore National Laboratory) also were measured to help identify the source and age of the sampled

  16. Ground-Water Quality Data in the Central Sierra Study Unit, 2006 - Results from the California GAMA Program

    USGS Publications Warehouse

    Ferrari, Matthew J.; Fram, Miranda S.; Belitz, Kenneth

    2008-01-01

    the results for these samples were used to evaluate the quality of the data for the ground-water samples. Results from field blanks indicated contamination was not a noticeable source of bias in the data for ground-water samples. Differences between replicate samples were within acceptable ranges, indicating acceptably low variability. Matrix spike recoveries were within acceptable ranges for most constituents. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, or blended with other waters to maintain water quality. Regulatory thresholds apply to water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CDPH), and thresholds established for aesthetic concerns (Secondary Maximum Contaminant Levels, SMCL-CA) by CDPH. Therefore, any comparisons of the results of this study to drinking-water standards only is for illustrative purposes and is not indicative of compliance or non-compliance to those standards. Most constituents that were detected in ground-water samples were found at concentrations below drinking-water standards or thresholds. Six constituents? fluoride, arsenic, molybdenum, uranium, gross-alpha radioactivity, and radon-222?were detected at concentrations higher than thresholds set for health-based regulatory purposes. Three additional constituents?pH, iron and manganese?were detected at concentrations above thresholds set for aesthetic concerns. Volatile organic compounds (VOCs) and pesticides, were detected in less than one-third of the samples and generally at less than one one-hundredth of a health-based threshold.

  17. Ground-Water Quality Data in the Southern Sacramento Valley, California, 2005 - Results from the California GAMA Program

    USGS Publications Warehouse

    Milby Dawson, Barbara J.; Bennett, George L.; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 2,100 square-mile Southern Sacramento Valley study unit (SSACV) was investigated from March to June 2005 as part of the Statewide Basin Assessment Project of Ground-Water Ambient Monitoring and Assessment (GAMA) Program. This study was designed to provide a spatially unbiased assessment of raw ground-water quality within SSACV, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 83 wells in Placer, Sacramento, Solano, Sutter, and Yolo Counties. Sixty-seven of the wells were selected using a randomized grid-based method to provide statistical representation of the study area. Sixteen of the wells were sampled to evaluate changes in water chemistry along ground-water flow paths. Four additional samples were collected at one of the wells to evaluate water-quality changes with depth. The GAMA Statewide Basin Assessment project was developed in response to the Ground-Water Quality Monitoring Act of 2001 and is being conducted by the California State Water Resources Control Board (SWRCB) in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory (LLNL). The ground-water samples were analyzed for a large number of man-made organic constituents (volatile organic compounds [VOCs], pesticides and pesticide degradates, pharmaceutical compounds, and wastewater-indicator constituents), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, and carbon-14, and stable isotopes of hydrogen, oxygen, and carbon), and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, matrix spikes

  18. Selected Ground-Water Data for Yucca Mountain Region, Southern Nevada and Eastern California, January-December 2005

    USGS Publications Warehouse

    Locke, Glenn L.

    2008-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of Energy, Office of Civilian Radioactive Waste Management, collected, compiled, and summarized hydrologic data in the Yucca Mountain region of southern Nevada and eastern California. These data were collected to allow assessments of ground-water resources during activities to determine the potential suitability or development of Yucca Mountain for storing high-level nuclear waste. Data collected from January through December 2005 are provided for ground-water levels at 35 boreholes and 1 fissure (Devils Hole), ground-water discharge at 5 springs, ground-water levels and discharge at 1 flowing borehole, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert. Ground-water level, discharge, and withdrawal data collected by other agencies, or as part of other programs, are provided. A statistical summary of ground-water levels at seven boreholes in Jackass Flats is presented for 1992-2005 to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the annual number of measurements; maximum, minimum, and median water-level altitudes; and average deviation of measured water-level altitudes compared to the 1992-93 baseline period. At seven boreholes in Jackass Flats, median water levels for 2005 were slightly higher (0.4-2.7 feet) than the median water levels for 1992-93.

  19. Bacteriophages as surface and ground water tracers

    NASA Astrophysics Data System (ADS)

    Rossi, P.; Dörfliger, N.; Kennedy, K.; Müller, I.; Aragno, M.

    Bacteriophages are increasingly used as tracers for quantitative analysis in both hydrology and hydrogeology. The biological particles are neither toxic nor pathogenic for other living organisms as they penetrate only a specific bacterial host. They have many advantages over classical fluorescent tracers and offer the additional possibility of multi-point injection for tracer tests. Several years of research make them suitable for quantitative transport analysis and flow boundary delineation in both surface and ground waters, including karst, fractured and porous media aquifers. This article presents the effective application of bacteriophages based on their use in differing Swiss hydrological environments and compares their behaviour to conventional coloured dye or salt-type tracers. In surface water and karst aquifers, bacteriophages travel at about the same speed as the typically referenced fluorescent tracers (uranine, sulphurhodamine G extra). In aquifers of interstitial porosity, however, they appear to migrate more rapidly than fluorescent tracers, albeit with a significant reduction in their numbers within the porous media. This faster travel time implies that a modified rationale is needed for defining some ground water protection area boundaries. Further developments of other bacteriophages and their documentation as tracer methods should result in an accurate and efficient tracer tool that will be a proven alternative to conventional fluorescent dyes.

  20. Hydrology, water quality, and ground-water-development alternatives in the Chipuxet ground-water reservoir, Rhode Island

    USGS Publications Warehouse

    Johnston, H.E.; Dickerman, D.C.

    1985-01-01

    A glacial sand and gravel aquifer in the Chipuxet River basin of Rhode Island forms a ground-water reservoir that could yield as much as 8.6 million gallons per day to wells; however, some streams would go dry for extended periods of time. The State Water Resources Board has tested five site that it proposes to develop for a public supply of 3 million gallons per day. A digital model was used to determine how withdrawal at this rate from alternative combinations of wells would affect water levels and streamflow. Results show that withdrawal of 3 million gallons per day would have a minimal effect on water levels, but that withdrawal at this rate from some well combinations could cause the Chipuxet River to have little or no flow for 90 consecutive days on the average of 1 year in 20. Quality of ground water is generally good, but leaching of fertilizers applied to croplands, which overlie much of the aquifer, has caused locally excessive concentrations of nitrate. Induced infiltration of surface water through organic sediments that line the bottoms of ponds and streams also seems to be the cause of elevated concentrations of manganese in water from some heavily pumped wells. (USGS)

  1. Selected ground-water data for Yucca Mountain Region, Southern Nevada and Eastern California, Calendar year 1993

    SciTech Connect

    Hale, G.S.; Westenburg, C.L.

    1995-07-01

    Data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 34 sites, ground-water discharge at 6 sites, and groundwater withdrawals within Jackass Flats, Mercury Valley, and Amargosa Desert are presented for calendar year 1993. Data on ground-water levels, discharges, and withdrawals collected by other agencies (or as part of other programs) are included to further indicate variations through time at selected monitoring locations. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented. The statistical summary includes the number of measurements, the maximum, minimum, and median or mean water-level altitudes, and the average or standard deviation of the water-level altitudes for selected baseline periods and for calendar years 1992 and 1993.

  2. Human interactions with ground-water

    USGS Publications Warehouse

    Zaporozec, A.

    1983-01-01

    Ground-Water could be considered as an immense reservoir, from which only a certain amount of water can be withdrawn without affecting the quantity and quality of water. This amount is determined by the characteristics of the environment in which ground-water occurs and by the interactions of ground-water with precipitation, surface water, and people. It should be recognized that quantity and quality of ground-water are intimately related and should be considered accordingly. Quantity refers to usable water and water is usable for any specific purpose only so long as its quality has not deteriorated beyond acceptable limits. Thus an overall quantitative and qualitative management of ground water is inevitable, and its should also involve the uses of ground-water reservoirs for purposes other than water supply. The main objective of ground-water management is to ensure that ground-water resources will be available in appropriate time and in appropriate quantity and quality to meet the most important demands of our society. Traditional, and obvious uses of ground-water are the extraction of water for water supplies (domestic, municipal, agricultural, and industrial) and the natural discharge feeding lakes and maintaining base flow of streams. Not so obvious are the uses of ground-water reservoirs, the very framework within which ground-water occurs and moves, and in which other fluids or materials can be stored. In the last two decades, ground-water reservoirs have been intensively considered for many other purposes than water supplies. Diversified and very often conflicting uses need to be evaluated and dealt with in the most efficient way in order to determine the importance of each possible use, and to assign priorities of these uses. With rising competition for the use of ground-water reservoirs, we will also need to increase the potential for effective planning of ground-water development and protection. Man's development and use of ground-water necessarily

  3. Simulation of ground-water flow and evaluation of water-management alternatives in the upper Charles River basin, eastern Massachusetts

    USGS Publications Warehouse

    DeSimone, Leslie A.; Walter, Donald A.; Eggleston, John R.; Nimiroski, Mark T.

    2002-01-01

    Ground water is the primary source of drinking water for towns in the upper Charles River Basin, an area of 105 square miles in eastern Massachusetts that is undergoing rapid growth. The stratified-glacial aquifers in the basin are high yield, but also are thin, discontinuous, and in close hydraulic connection with streams, ponds, and wetlands. Water withdrawals averaged 10.1 million gallons per day in 1989?98 and are likely to increase in response to rapid growth. These withdrawals deplete streamflow and lower pond levels. A study was conducted to develop tools for evaluating water-management alternatives at the regional scale in the basin. Geologic and hydrologic data were compiled and collected to characterize the ground- and surface-water systems. Numerical flow modeling techniques were applied to evaluate the effects of increased withdrawals and altered recharge on ground-water levels, pond levels, and stream base flow. Simulation-optimization methods also were applied to test their efficacy for management of multiple water-supply and water-resource needs. Steady-state and transient ground-water-flow models were developed using the numerical modeling code MODFLOW-2000. The models were calibrated to 1989?98 average annual conditions of water withdrawals, water levels, and stream base flow. Model recharge rates were varied spatially, by land use, surficial geology, and septic-tank return flow. Recharge was changed during model calibration by means of parameter-estimation techniques to better match the estimated average annual base flow; area-weighted rates averaged 22.5 inches per year for the basin. Water withdrawals accounted for about 7 percent of total simulated flows through the stream-aquifer system and were about equal in magnitude to model-calculated rates of ground-water evapotranspiration from wetlands and ponds in aquifer areas. Water withdrawals as percentages of total flow varied spatially and temporally within an average year; maximum values were

  4. Use of Microgravity to Assess the Effects of El Nino on Ground-Water Storage in Southern Arizona

    USGS Publications Warehouse

    Parker, John T.C.; Pool, Donald R.

    1998-01-01

    The availability of ground water is of extreme importance in areas, such as southern Arizona, where it is the main supply for agricultural, industrial, or domestic purposes. Where ground-water use exceeds recharge, monitoring is critical for managing water supplies. Typically, monitoring has been done by measuring water levels in wells; however, this technique only partially describes ground-water conditions in a basin. A new application of geophysical technology is enabling U.S. Geological Survey (USGS) scientists to measure changes in the amount of water in an aquifer using a network of microgravity stations. This technique enables a direct measurement of ground-water depletion and recharge. In Tucson, Arizona, residents have relied solely upon ground water for most of their needs since the 19th century. Water levels in some wells in the Tucson area have declined more than 200 ft in the past 50 years. Similar drops in water levels have occurred elsewhere in Arizona. In response to the overdrafting of ground water, the State of Arizona passed legislation designed to attain 'safe yield,' which is defined as a balance between ground-water withdrawals and annual recharge of aquifers. To monitor progress in complying with the legislation, ground-water withdrawals are measured and estimated, and annual recharge is estimated. The Tucson Basin and Avra Valley are two ground-water basins that form the Tucson Active Management Area (TAMA), which by State statute must attain 'safe yield' by the year 2025.

  5. Ground-Water Recharge from Small Intermittent Streams in the Western Mojave Desert, California

    USGS Publications Warehouse

    Izbicki, John A.; Johnson, Russell U.; Kulongoski, Justin T.; Predmore, Steven

    2007-01-01

    Population growth has impacted ground-water resources in the western Mojave Desert, where declining water levels suggest that recharge rates have not kept pace with withdrawals. Recharge from the Mojave River, the largest hydrographic feature in the study area, is relatively well characterized. In contrast, recharge from numerous smaller streams that convey runoff from the bounding mountains is poorly characterized. The current study examined four representative streams to assess recharge from these intermittent sources. Hydraulic, thermal, geomorphic, chemical, and isotopic data were used to study recharge processes, from streamflow generation and infiltration to percolation through the unsaturated zone. Ground-water movement away from recharge areas was also assessed. Infiltration in amounts sufficient to have a measurable effect on subsurface temperature profiles did not occur in every year in instrumented study reaches. In addition to streamflow availability, results showed the importance of sediment texture in controlling infiltration and eventual recharge. Infiltration amounts of about 0.7 meters per year were an approximate threshold for the occurrence of ground-water recharge. Estimated travel times through the thick unsaturated zones underlying channels reached several hundred years. Recharging fluxes were influenced by stratigraphic complexity and depositional dynamics. Because of channel meandering, not all water that penetrates beneath the root zone can be assumed to become recharge on active alluvial fans. Away from study washes, elevated chloride concentrations and highly negative water potentials beneath the root zone indicated negligible recharge from direct infiltration of precipitation under current climatic conditions. In upstream portions of washes, generally low subsurface chloride concentrations and near-zero water potentials indicated downward movement of water toward the water table, driven primarily by gravity. Recharging conditions did not

  6. Ground-water studies and analog models

    USGS Publications Warehouse

    Robinove, Charles Joseph

    1962-01-01

    Hydrologists make ground-water studies to aid managers and users of water resources in solving their problems in the development and management of ground water. Geologic and hydrologic information provides the basic knowledge for construction of electric analog models that portray the ground-water system in miniature. Analog models can be analyzed electrically, and the results of the analysis are presented in terms of the ground-water system so that the effects of alternative methods of water development can be assessed.

  7. Ground water in the Pullman area, Whitman County, Washington

    USGS Publications Warehouse

    Foxworthy, B.L.; Washburn, R.L.

    1963-01-01

    This report presents the results of an investigation of the ground-water resources of the Pullman area, Whitman County, Wash. The investigation war made in cooperation with the State of Washington, Department of Conservation, Division of Water Resources, to determine whether the 1959 rate of ground-water withdrawal exceeded the perennial yield of the developed aquifers, and if so, (1) whether additional aquifers could be developed in the area, and (2) whether the yield of the developed aquifers could be increased by artificial recharge. The Pullman area includes the agricultural district surrounding the city of Pullman, in southeastern Whitman County, and the western two-thirds of the Moscow-Pullman basin, which extends into Latah County, Idaho. The mapped area comprises shout 250 square miles. The area is in a region of smooth rolling hills formed by erosion of thick deposits of loess, which cover a dissected lava plain. The loess (Palouse formation of Pleistocene age) ranges in thickness from less than 1 foot to more than 150 feet. The underlying lava flows, part of the Columbia River basalt of Tertiary age, are nearly horizontal and form bluffs and low cliffs along the major streams. The total thickness of the basalt sequence in the area is not known, but it may be considerably greater than 1,000 feet beneath the city of Pullman. The basalt sequence is underlain by a basement mass of granite, granite gneiss, and quartzite, of pre-Tertiary age. The most productive aquifers in the area are in the Columbia River basalt. They consist of the permeable zones, commonly occurring at the tops of individual lava flows, which may contain ground water under either artesian or water-table conditions. Two such permeable zones have produced more than 95 percent of the ground water used in the Pullman area, or as much as 870 million gallons per year (1957). These two zones are hydraulically connected and lie at depths ranging from about 50 to 170 feet below the land surface at

  8. Carbon biogeochemistry of ground water, Guiyang, southwest China.

    PubMed

    Li, Si-Liang; Liu, Cong-Qiang; Tao, Fa-Xiang; Lang, Yun-Chao; Han, Gui-Lin

    2005-01-01

    Variations in the concentrations and isotopic compositions (delta13C(DIC)) of dissolved inorganic carbon (DIC) reflect contamination and biogeochemical cycling of the carbon in ground water. In order to understand contamination and biogeochemical cycling of DIC, we carried out research on the geochemistry of ground water of Guiyang, the capital city of Guizhou Province, China. Results show that ground water is mainly characterized by SO4.HCO3-Ca.Mg and HCO3-Ca.Mg chemical compositions. The hydrochemical characteristics of these types of water are mainly controlled by lithology of the aquifers. HCO3- is the dominant species of DIC in ground water and has lower concentrations and more negative values of delta13C(DIC) in the high-flow (summer monsoon) season, as compared to the low-flow season. This indicates that DIC is relatively enriched in carbon of biological origin in the high-flow season as compared to the low-flow season and that biological activities are the predominant control on shifts of stable carbon isotope values. The evidence that the delta13C(DIC) values of ground water decrease with increasing concentrations of anthropogenic species shows that the carbon isotopic composition of DIC can be a useful tracer of contamination, in addition to biogeochemical cycling of inorganic carbon in ground water. Results from this study show that ground water is impacted by significant levels of contamination from human activities, especially in the urban areas, as well as the northeast and west suburbs, in Guiyang city, southwest China. PMID:16029175

  9. Hanford Site ground-water monitoring for 1993

    SciTech Connect

    Dresel, P.E.; Luttrell, S.P.; Evans, J.C.

    1994-09-01

    This report presents the results of the Ground-Water Surveillance Project monitoring for calendar year 1993 on the Hanford Site, Washington. Hanford Site operations from 1943 onward produced large quantities of radiological and chemical waste that have impacted ground-water quality on the Site. Monitoring of water levels and ground-water chemistry is performed to track the extent of contamination and trends in contaminant concentrations. The 1993 monitoring was also designed to identify emerging ground-water quality problems. The information obtained is used to verify compliance with applicable environmental regulations and to evaluate remedial actions. Data from other monitoring and characterization programs were incorporated to provide an integrated assessment of Site ground-water quality. Additional characterization of the Site`s geologic setting and hydrology was performed to support the interpretation of contaminant distributions. Numerical modeling of sitewide ground-water flow also supported the overall project goals. Water-level monitoring was performed to evaluate ground-water flow directions, to track changes in water levels, and to relate such changes to changes in site disposal practices. Water levels over most of the Hanford Site continued to decline between June 1992 and June 1993. The greatest declines occurred in the 200-West Area. These declines are part of the continued response to the cessation of discharge to U Pond and other disposal facilities. The low permeability in this area which enhanced mounding of waste-water discharge has also slowed the response to the reduction of disposal. Water levels remained nearly constant in the vicinity of B Pond, as a result of continued disposal to the pond. Water levels measured from wells in the unconfined aquifer north and east of the Columbia River indicate that the primary source of recharge is irrigation practices.

  10. Ground-water resources of Cumberland County, New Jersey

    USGS Publications Warehouse

    Rooney, James G.

    1971-01-01

    Water use in Cumberland County varies and is highly seasonal, mainly because of increasing requirements for irrigation and the food processing industries in the county. In 1964 seasonal use ranged from 27 mgd in March to 145 mgd in August. This is much higher than withdrawals in neighboring Salem and Cape May Counties. In 1964 withdrawals in Cumberland County averaged about 51 mgd; almost all of this, 49.4 mgd, was from ground-water supplies. The total annual water use in 1964 according to type of use was: for public supply, 10.6 mgd; for industrial uses, 19.0 mgd; irrigation, 15.4 mgd; suburban, rural, residential, institutional, farm, and commercial, 5.9 mgd. 

  11. Bibliography of publications relating to ground water in Connecticut

    USGS Publications Warehouse

    Cushman, R.V.

    1950-01-01

    In 1939, when it became necessary to curtail the work being carried on by the Works Progress Administration, cooperation was arranged between the Federal Ecological Survey and the State Water Commission to continue investigations relative to the over-development of ground-water supplies in the New Haven area. From time to time additional funds have been made available to meet growing demands by the State for data on its ground-water supplied and the present cooperative program between the U.S. Geological Survey and the State Water Commission is a continuation of the original arrangement. It is estimated that about 14 per cont of the State has been covered by recent ground-water surveys and in addition some data are available for another 20 per cent of he State.

  12. Annual summary of ground-water conditions in Arizona, spring 1979 to spring 1980

    USGS Publications Warehouse

    ,

    1981-01-01

    Withdrawal of ground water, about 4.0 million acre-feet in Arizona in 1979, is about 200,000 acre-feet less than the amount withdrawn in 1978. The withdrawals in 1978 and 1979 are the smallest since the mid-1950 's except in 1966. Nearly all the decrease was in the amount of ground water used for irrigation in the Basin and Range lowlands province. The large amount of water in storage in the surface-water reservoirs, release of water from the reservoirs, floods, and conservation practices contributed to the decrease in ground-water use and caused water-level rises in the Salt River Valley, Gila Bend basin, and Gila River drainage from Painted Rock Dam to Texas Hill. Two small-scale maps show ground-water pumpage by areas and the status of the ground-water inventory in the State. The main map, which is at a scale of 1:500,000, shows potential well production, depth to water in selected wells in spring 1980, and change in water level in selected wells from 1975 to 1980. A brief text summarizes the current ground-water conditions in the State. (USGS)

  13. Ground-Water Quality Data in the Kern County Subbasin Study Unit, 2006 - Results from the California GAMA Program

    USGS Publications Warehouse

    Shelton, Jennifer L.; Pimentel, Isabel; Fram, Miranda S.; Belitz, Kenneth

    2008-01-01

    Ground-water quality in the approximately 3,000 square-mile Kern County Subbasin study unit (KERN) was investigated from January to March, 2006, as part of the Priority Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin Assessment project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the California State Water Resources Control Board (SWRCB) in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory (LLNL). The Kern County Subbasin study was designed to provide a spatially unbiased assessment of raw (untreated) ground-water quality within KERN, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 50 wells within the San Joaquin Valley portion of Kern County. Forty-seven of the wells were selected using a randomized grid-based method to provide a statistical representation of the ground-water resources within the study unit. Three additional wells were sampled to aid in the evaluation of changes in water chemistry along regional ground-water flow paths. The ground-water samples were analyzed for a large number of man-made organic constituents (volatile organic compounds [VOCs], pesticides, and pesticide degradates), constituents of special interest (perchlorate, N-nitrosodimethylamine [NDMA], and 1,2,3-trichloropropane [1,2,3-TCP]), naturally occurring inorganic constituents (nutrients, major and minor ions, and trace elements), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14, and stable isotopes of hydrogen, oxygen, nitrogen, and carbon) and dissolved noble gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, and laboratory matrix spikes) were collected and analyzed at approximately 10 percent of

  14. Evaluation of baseline ground-water conditions in the Mosteiros, Ribeira Paul, and Ribeira Faja Basins, Republic of Cape Verde, West Africa, 2005-06

    USGS Publications Warehouse

    Heilweil, Victor M.; Earle, John D.; Cederberg, Jay R.; Messer, Mickey M.; Jorgensen, Brent E.; Verstraeten, Ingrid M.; Moura, Miguel A.; Querido, Arrigo; Spencer,; Osorio, Tatiana

    2006-01-01

    This report documents current (2005-06) baseline ground-water conditions in three basins within the West African Republic of Cape Verde (Mosteiros on Fogo, Ribeira Paul on Santo Ant?o, and Ribeira Faj? on S?o Nicolau) based on existing data and additional data collected during this study. Ground-water conditions (indicators) include ground-water levels, ground-water recharge altitude, ground-water discharge amounts, ground-water age (residence time), and ground-water quality. These indicators are needed to evaluate (1) long-term changes in ground-water resources or water quality caused by planned ground-water development associated with agricultural projects in these basins, and (2) the feasibility of artificial recharge as a mitigation strategy to offset the potentially declining water levels associated with increased ground-water development. Ground-water levels in all three basins vary from less than a few meters to more than 170 meters below land surface. Continuous recorder and electric tape measurements at three monitoring wells (one per basin) showed variations between August 2005 and June 2006 of as much as 1.8 meters. Few historical water-level data were available for the Mosteiros or Ribeira Paul Basins. Historical records from Ribeira Faj? indicate very large ground-water declines during the 1980s and early 1990s, associated with dewatering of the Galleria Faj? tunnel. More-recent data indicate that ground-water levels in Ribeira Faj? have reached a new equilibrium, remaining fairly constant since the late 1990s. Because of the scarcity of observation wells within each basin, water-level data were combined with other techniques to evaluate ground-water conditions. These techniques include the quantification of ground-water discharge (well withdrawals, spring discharge, seepage to springs, and gallery drainage), field water-quality measurements, and the use of environmental tracers to evaluate sources of aquifer recharge, flow paths, and ground-water

  15. Guide to Louisiana's ground-water resources

    USGS Publications Warehouse

    Stuart, C.G.; Knochenmus, D.D.; McGee, B.D.

    1994-01-01

    Ground water is one of the most valuable and abundant natural resources of Louisiana. Of the 4-.4 million people who live in the State, 61 percent use ground water as a source for drinking water. Most industrial and rural users and half of the irrigation users in the State rely on ground water. Quantity, however, is not the only aspect that makes ground water so valuable; quality also is important for its use. In most areas, little or no water treatment is required for drinking water and industrial purposes. Knowledge of Louisiana's ground-water resources is needed to ensure proper development and protection of this valuable resource. This report is designed to inform citizens about the availability and quality of ground water in Louisiana. It is not intended as a technical reference; rather, it is a guide to ground water and the significant role this resource plays in the state. Most of the ground water that is used in the State is withdrawn from 13 aquifers and aquifer systems: the Cockfield, Sparta, and Carrizo-Wilcox aquifersin northern Louisiana; Chicot aquifer system, Evangeline aquifer, Jasper aquifer system, and Catahoula aquifer in central and southwestern Louisiana; the Chicot equivalent, Evangeline equivalent, and Jasper equivalent aquifer systems in southeastern Louisiana; and the MississippiRiver alluvial, Red River alluvial, and upland terrace aquifers that are statewide. Ground water is affected by man's activities on the land surface, and the major ground-water concerns in Louisiana are: (1) contamination from surface disposal of hazardous waste, agricultural chemicals, and petroleum products; (2) contamination from surface wastes and saltwater through abandoned wells; (3) saltwater encroachment; and (4) local overdevelopment. Information about ground water in Louisiana is extensive and available to the public. Several State and Federal agencies provide published and unpublished material upon request.

  16. Use of a ground-water flow model with particle tracking to evaluate ground-water vulnerability, Clark County, Washington

    USGS Publications Warehouse

    Snyder, D.T.; Wilkinson, J.M.; Orzol, L.L.

    1996-01-01

    public-supply wells in Clark County may be receiving a component of water that recharged in areas that are more conducive to contaminant entry. The aquifer sensitivity maps illustrate a critical deficiency in the DRASTIC methodology: the failure to account for the dynamics of the ground-water flow system. DRASTIC indices calculated for a particular location thus do not necessarily reflect the conditions of the ground-water resources at the recharge areas to that particular location. Each hydrogeologic unit was also mapped to highlight those areas that will eventually receive flow from recharge areas with on-site waste-disposal systems. Most public-supply wells in southern Clark County may eventually receive a component of water that was recharged from on-site waste-disposal systems.Traveltimes from particle tracking were used to estimate the minimum and maximum age of ground water within each model-grid cell. Chlorofluorocarbon (CFC)-age dating of ground water from 51 wells was used to calibrate effective porosity values used for the particle- tracking program by comparison of ground-water ages determined through the use of the CFC-age dating with those calculated by the particle- tracking program. There was a 76 percent agreement in predicting the presence of modern water in the 51 wells as determined using CFCs and calculated by the particle-tracking program. Maps showing the age of ground water were prepared for all the hydrogeologic units. Areas with the youngest ground-water ages are expected to be at greatest risk for contamination from anthropogenic sources. Comparison of these maps with maps of public- supply wells in Clark County indicates that most of these wells may withdraw ground water that is, in part, less than 100 years old, and in many instances less than 10 years old. Results of the analysis showed that a single particle-tracking analysis simulating advective transport can be used to evaluate ground-water vulnerability for any part of a ground-wate

  17. Ground water in the Verdigris River basin, Kansas and Oklahoma

    USGS Publications Warehouse

    Fader, Stuart Wesley; Morton, Robert B.

    1975-01-01

    Ground water in the Verdigris River basin occurs in consolidated rocks and unconsolidated deposits ranging in age from Mississippian to Quaternary. Water for municipal, industrial, and irrigation supplies generally can be obtained in limited quantities from the alluvial deposits in the stream valleys. Except for water in the alluvial deposits in the stream valleys and in the outcrop areas of the bedrock aquifers, the groundwater is generally of poor chemical quality. Owing to the generally poor chemical quality of water and low yields to wells, an increase in the use of ground water from the consolidated rocks is improbable. The unconsolidated rocks in the Verdigris River basin receive about 166,000 acre-feet of recharge annually, and about 1 million acre-fee of water is in temporary storage in the deposits. In 1968 about 4,200 acre-feet of ground was withdrawn for all uses. About 800 acre-feet of ground and 5,000 acre-feet of surface water were pumped for irrigation of 5,300 acres of cropland. The total annual withdrawal of ground water for irrigation may be 2,000 acre-feet by the year 2000.

  18. Simulation of ground-water flow in the Potomac-Raritan-Magothy aquifer system, Pennsauken Township and vicinity, New Jersey

    USGS Publications Warehouse

    Pope, Daryll A.; Watt, Martha K.

    2004-01-01

    The Potomac-Raritan-Magothy aquifer system is one of the primary sources of potable water in the Coastal Plain of New Jersey, particularly in heavily developed areas along the Delaware River. In Pennsauken Township, Camden County, local drinking-water supplies from this aquifer system have been contaminated by hexavalent chromium at concentrations that exceed the New Jersey maximum contaminant level. In particular, ground water at the Puchack well field has been adversely affected to the point where, since 1984, water is no longer withdrawn from this well field for public supply. The area that contains the Puchack well field was added to the National Priorities List in 1998 as a Superfund site. The U.S. Geological Survey (USGS) conducted a reconnaissance study from 1996 to 1998 during which hydrogeologic and water-quality data were collected and a ground-water-flow model was developed to describe the conditions in the aquifer system in the Pennsauken Township area. The current investigation by the USGS, in cooperation with the U.S. Environmental Protection Agency (USEPA), is an extension of the previous study. Results of the current study can be applied to a Remedial Investigation and Feasibility Study conducted at the Puchack well field Superfund site. The USGS study collected additional data on the hydrogeology and water-quality in the area. These data were incorporated into a refined model of the ground-water-flow system in the Potomac-Raritan-Magothy aquifer system. A finite-difference model was developed to simulate ground-water flow and the advective transport of chromium-contaminated ground water in the aquifers of the Potomac-Raritan-Magothy aquifer system in the Pennsauken Township area. An 11-layer model was used to represent the complex hydrogeologic framework. The model was calibrated using steady-state water-level data from March 1998, April 1998, and April 2001. Water-level recovery during the shutdown of Puchack 1 during March to April 1998 was

  19. Case study: Hydrogeology, contaminant transport, and remediation in an anisotropic, fractured bedrock ground-water system

    SciTech Connect

    Roach, L.F.; Robertson, C.G. )

    1993-10-01

    The site has a 30-year history of low-volume halogenated solvent usage and is located in an area of New York underlain by mica schist bedrock which is covered by glacial deposits. Dilute waste-water releases resulted in a 2,000-foot long plume of dissolved volatile organic compounds, the shape of which reflects the control of bedrock fractures on ground-water flow conditions. The site has a large number of bedrock monitoring points with 34 bedrock monitoring wells located in or near the plume, including nine bedrock monitoring well clusters. Constant rate aquifer tests of at least 36-hour duration were conducted at five bedrock wells at various positions within the plume. Remediation to date consists of three years of bedrock ground-water withdrawal at near-source and downgradient locations for hydraulic control and areal reduction of the plume. The combined drawdown produced by these two pumping centers conforms to the drawdown predicted by the additive drawdowns observed in individual aquifer tests. VOC concentrations within the plume are decreasing rapidly with some wells experiencing a reduction in VOC concentrations of greater than 90%. The plume area has been reduced by approximately 50%.

  20. Hydrogeology of, and ground-water flow in, a valley-fill and carbonate-rock aquifer system near Long Valley in the New Jersey Highlands

    USGS Publications Warehouse

    Nicholson, R.S.; McAuley, S.D.; Barringer, J.L.; Gordon, A.D.

    1996-01-01

    The hydrogeology of and ground-water flow in a valley-fill and carbonate-rock aquifer system were evaluated by using numerical-modeling techniques and geochemical interpretations to address concerns about the adequacy of the aquifer system to meet increasing demand for water. The study was conducted during 1987-90 by the U.S. Geological Survey, in cooperation with the New Jersey Department of Environmental Protection and Energy. The effects of recent and anticipated ground-water withdrawals on water levels, stream base flows, and water budgets were estimated. Simulation results indicate that recent withdrawals of 4.7 million gallons per day have resulted in water-level declines of up to 35 feet. Under conditions of increases in withdrawals of 121 percent, water levels would decline up to an additional 28 feet. The magnitude of predicted average base-flow depletion, when compared with historic low flows, indicates that projected increases in withdrawals may substantially deplete seasonal low flow of Drakes Brook and South Branch Raritan River. Results of a water-budget analysis indicate that the sources of water to additional supply wells would include leakage from the overlying valley-fill aquifer and induced leakage of surface water into the aquifer system. Results of water-quality analyses indicate that human activities are affecting the quality of the ground water. With the exception of an elevated iron concentration in water from one well, concentrations of inorganic constituents in water from 75 wells did not exceed New Jersey primary or secondary drinking-water regulations. Volatile organic compounds were detected in water from several wells; in two samples, concentrations of specific compounds exceeded drinking-water regulations.

  1. GROUND-WATER TECHNICAL SUPPORT CENTER

    EPA Science Inventory

    This flyer describes the objectives and activities of the Ground-Water Technical Support Center, which is part of the Ground Water and Ecosystems Restoration Division. It is directed toward technical audiences (EPA Regions and State regulators within the Regions) and will be use...

  2. Mississippi Embayment Regional Ground Water Study

    EPA Science Inventory

    Increased water usage in the southeastern United States in the tri-state area of Tennessee, Mississippi and Arkansas poses a dilemma to ensuring long-term sustainability of the quantity and quality of ground-water resources that underlie the region. Demand for ground water by ag...

  3. Ground water near Newton, Jasper County, Iowa

    USGS Publications Warehouse

    Buchmiller, Robert C.

    2001-01-01

    The water quality in the South Skunk River and the alluvial aquifer was similar, except most ground-water samples contained low dissolved oxygen concentrations. The low dissolved-oxygen concentrations in ground water resulted in high concentrations of iron and manganese in some locations and reduced forms of nitrogen.

  4. Procedures for ground-water investigations

    SciTech Connect

    Not Available

    1992-12-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water monitoring procedures are developed and used in accordance with the PNL Quality Assurance Program.

  5. Ground water resources of Lee County

    USGS Publications Warehouse

    Gordon, Donivan L.

    1980-01-01

    In terms of these factors, there are few locations in Lee County where the availability of ground water is not limited to some degree. The most common limitation is poor water quality, that is, highly mineralized ground water. Secondary limitations are generally related to poor distribution, small yields from some sources, and poor accessibility due to the great depths to adequate sources.

  6. FUNDAMENTALS OF GROUND-WATER MODELING

    EPA Science Inventory

    Ground-water flow and contaminant transport modeling has been used at many hazardous waste sites with varying degrees of success. odels may be used throughout all phases of the site investigation and remediation processes. eveloping a better understanding of ground-water modeling...

  7. Maps showing ground-water conditions in the Douglas Basin area, Cochise County, Arizona; 1978

    USGS Publications Warehouse

    Mann, Larry J.; English, C.S.

    1980-01-01

    The Douglas basin area includes about 1,200 square miles in southeastern Arizona. The main use of ground water is for irrigation. For 1955-77, the estimated ground-water pumpage equaled or exceeded 50,000 acre-feet per year, and for 1966-77, the ground-water pumpage averaged about 109,000 acre-feet per year. Ground-water withdrawals have resulted in water-level declines in most of the area. Information shown on the maps includes change in water level (1966-78) and irrigated area; depth to water and altitude of the water level; and chemical quality of the water and well depth. Hydrographs of the water level in selected wells and a table of historical pumpage also are included. Scale 1:125,000. (USGS)

  8. Ground-water availability on the Kitsap Peninsula, Washington

    USGS Publications Warehouse

    Hansen, Arnold J.; Bolke, E.L.

    1980-01-01

    Unconsolidated deposits on the Kitsap Peninsula, Wash., are of glacial and interglacial origin. These deposits were divided into three units based on lithology and hydraulic properties. Two of the three units are composed of layers of sand and gravel , and silt and clay. The third unit consists of silt and clay and in most places separates the other two units. Water-bearing strata in the upper unit are fairly continuous and average 15 feet in thickness. The lower water-bearing strata are not believed to be as continuous as those in the upper unit, but yield larger quantities of water to wells. The silt-and-clay unit averages 70 feet in thickness, occurs generally near sea level, and is not known to contain major water-bearing deposits. The average annual ground-water recharge to streams on the Kitsap Peninsula was estimated to be 17 times the 1975 annual ground-water pumpage for the peninsula. Some, but an unknown amount, of this water is available for increased withdrawal by wells. Increased withdrawals cause decreased streamflow, declining water levels, and increased seawater contamination. There appears to be no widespread seawater contamination of wells in the study area. Local areas where chloride concentrations from wells exceed 25 milligrams per liter are near the southern part of the Longbranch Peninsula, Horsehead Bay, Point Evans, Sinclair Inlet, Eagle Harbor, Fletcher Bay, the northern end of Bainbridge Island, and the northern tip of the Kitsap Peninsula. (USGS)

  9. Availability of ground water in the lower Pawcatuck River basin, Rhode Island

    USGS Publications Warehouse

    Gonthier, Joseph B.; Johnston, Herbert E.; Malmberg, Glenn T.

    1974-01-01

    streamflow downstream from pumping centers but generally will not result in streams going dry, provided the water is returned to the basin. Export of water from the basin will require careful consideration of the effects of such withdrawals on low streamflow. Export from the Pawcatuck basin of 27 million gallons per day, estimated to be available from ground-water reservoirs in the upper Pawcatuck basin, in addition to 37.5 million gallons per day available in the lower Pawcatuck basin, will markedly reduce low streamflow. The 90-percent duration flow of the Pawcatuck River at Westerly would be reduced from 75 million gallons per day to perhaps as little as 21 million gallons per day. The chemical quality of water from both the sand and gravel aquifer and associated streams is suitable for most purposes. The water is soft, slightly acidic, and typically has a dissolved-solids content of less than 75 milligrams per liter. Some treatment may be required locally for removal of iron and manganese to meet recommended standards of the U.S. Public Health Service for drinking water.

  10. Arsenic contamination in ground water: Indian scenario.

    PubMed

    Jain, C K

    2002-07-01

    The ground water in a huge alluvial tract along the river Hooghly covering a stretch of about 470 km., encompassing eight districts in the state of West Bengal (India) is affected by arsenic pollution of ground water. The probable source of arsenic has been reported to be through geological formations. Occurrence of iron-pyrite and the change of geo-chemical environment due to over-exploitation of ground water or excessive fluctuation of ground water table are the possible reasons of decomposition of pyrite to ferrous sulphate, ferric sulphate and sulfuric acid. However, no definite explanation regarding the source of arsenic could be established so far. Keeping in view the severity of the problem, an attempt has been made to bring out the nature and extent of arsenic problem in ground water of West Bengal, India, as well as need for watershed management to combat the situation.

  11. Arsenic in Illinois ground water : community and private supplies

    USGS Publications Warehouse

    Warner, Kelly L.; Martin, Angel; Arnold, Terri L.

    2003-01-01

    Assessing the distribution of arsenic in ground water from community-water supplies, private supplies, or monitoring wells is part of the process of determining the risk of arsenic contamination of drinking water in Illinois. Lifestyle, genetic, and environmental factors make certain members of the population more susceptible to adverse health effects from repeated exposure to drinking water with high arsenic concentrations (Ryker, 2001). In addition, such factors may have geographic distribution patterns that complicate the analysis of the relation between arsenic in drinking water and health effects. For example, arsenic may not be the only constituent affecting the quality of drinking water in a region (Ryker, 2001); however, determining the extent and distribution of arsenic in ground water is a starting place to assess the potential risk for persons drinking from a community or private supply. Understanding the potential sources and pathways that mobilize arsenic in ground water is a necessary step in protecting the drinking-water supply in Illinois.

  12. Geology and ground-water resources of Galveston County, Texas

    USGS Publications Warehouse

    Petitt, Ben McDowell; Winslow, Allen George

    1957-01-01

    Much additional ground water could be obtained from both the "Alta Loma" sand and the upper part of the Beaumont clay, especially in the northern and western parts of the county. Before large developments of supplies are planned, however, these areas should be explored by test drilling. The problems of well spacing and pumping rates should be thoroughly studied in order to determine the maximum development permitted by the ground-water supply. Current observations should be continued with special emphasis on the progress of salt-water encroachment.

  13. Ground-water quality in Wisconsin through 1972

    USGS Publications Warehouse

    Skinner, E.L.; Holt, C. L. R.

    1972-01-01

    Ground water, a plentiful and largely underdeveloped resource of Wisconsin, has good to excellent chemical quality in most places. This resource is readily available in most parts of the State for municipal, industrial, and rural uses. In 1970, about 0.5 billion gallons of ground water a day was pumped in Wisconsin for all uses (Murray and Reeves, 1972). In addition, underground reservoirs discharge an average of 16 billion gallons per day of water of relatively constant temperature and uniform quality, which maintains the base flow of streams and the level of lakes (Holt, 1964).

  14. Selected Ground-Water Data for Yucca Mountain Region, Southern Nevada and Eastern California, Through December 1992

    USGS Publications Warehouse

    La Camera, Richard J.; Westenburg, Craig L.

    1994-01-01

    Tne U.S. Geological Survey. in support of the U.S. Department of Energy, Yucca Mountain Site- Characterization Project, collects, compiles, and summarizes water-resource data in the Yucca Mountain region. The data are collected to document the historical and current condition of ground-water resources, to detect and document changes in those resources through time, and to allow assessments of ground-water resources during investigations to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 36 sites, ground- water discharge at 6 sites, ground-water quality at 19 sites, and ground-water withdrawals within Crater Fiat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented. Data on ground-water levels, discharges, and withdrawals collected by other agencies or as part of other programs are included to further indicate variations through time. A statistical summary of ground-water levels and median annual ground-water withdrawals in Jackass Flats is presented. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of a11 water-level altitudes for selected baseline periods and for calendar year 1992. Data on ground-water quality are compared to established, proposed, or tentative primary and secondary drinking-water standards, and measures which exceeded those standards are listed for 18 sites. Detected organic compounds for which established, proposed, or tentative drinking-water standards exist also are listed.

  15. Simulation of selected ground-water pumping scenarios at Fort Stewart and Hunter Army Airfield, Georgia

    USGS Publications Warehouse

    Cherry, Gregory S.

    2006-01-01

    A regional MODFLOW ground-water flow model of parts of coastal Georgia, Florida, and South Carolina was used to evaluate the effects of current and hypothetical groundwater withdrawal, and the relative effects of pumping in specific areas on ground-water flow in the Upper Floridan aquifer near Fort Stewart and Hunter Army Airfield (HAAF), coastal Georgia. Simulation results for four steady-state pumping scenarios were compared to each other and to a Base Case condition. The Base Case represents year 2000 pumping rates throughout the model area, with the exception that permitted annual average pumping rates for the year 2005 were used for 26 production wells at Fort Stewart and HAAF. The four pumping scenarios focused on pumping increases at HAAF resulting from projected future demands and additional personnel stationed at the facility and on reductions in pumping at Fort Stewart. Scenarios A and B simulate 1- and 2-million-gallon-perday (Mgal/d) increases, respectively, at HAAF. Simulated water-level change maps for these scenarios indicate an area of influence that extends into parts of Bryan, Bulloch, Chatham, Effingham, and Liberty Counties, Ga., and Beaufort and Jasper Counties, S.C., with maximum drawdowns from 0.5 to 4 feet (ft) for scenario A and 1 to 8 ft for Scenario B. For scenarios C and D, increases in pumping at HAAF were offset by decreases in pumping at Fort Stewart. Scenario C represents a 1-Mgal/d increase at HAAF and a 1-Mgal/d decrease at Fort Stewart; simulated water-level changes range from 0.4 to -4 ft. Scenario D represents a 2-Mgal/d increase at HAAF and 2-Mgal/d decrease at Fort Stewart; simulated water-level changes range from 0.04 to -8 ft. The simulated water-level changes indicate an area of influence that extends into parts of Bryan, Bulloch, Chatham, Effingham, Liberty, and McIntosh Counties, Ga., and Jasper and Beaufort Counties, S.C. In general, decreasing pumping at Fort Stewart by an equivalent amount to pumping increases at HAAF

  16. Regional ground-water evapotranspiration and ground-water budgets, Great Basin, Nevada

    USGS Publications Warehouse

    Nichols, William D.

    2000-01-01

    PART A: Ground-water evapotranspiration data from five sites in Nevada and seven sites in Owens Valley, California, were used to develop equations for estimating ground-water evapotranspiration as a function of phreatophyte plant cover or as a function of the depth to ground water. Equations are given for estimating mean daily seasonal and annual ground-water evapotranspiration. The equations that estimate ground-water evapotranspiration as a function of plant cover can be used to estimate regional-scale ground-water evapotranspiration using vegetation indices derived from satellite data for areas where the depth to ground water is poorly known. Equations that estimate ground-water evapotranspiration as a function of the depth to ground water can be used where the depth to ground water is known, but for which information on plant cover is lacking. PART B: Previous ground-water studies estimated groundwater evapotranspiration by phreatophytes and bare soil in Nevada on the basis of results of field studies published in 1912 and 1932. More recent studies of evapotranspiration by rangeland phreatophytes, using micrometeorological methods as discussed in Chapter A of this report, provide new data on which to base estimates of ground-water evapotranspiration. An approach correlating ground-water evapotranspiration with plant cover is used in conjunction with a modified soil-adjusted vegetation index derived from Landsat data to develop a method for estimating the magnitude and distribution of ground-water evapotranspiration at a regional scale. Large areas of phreatophytes near Duckwater and Lockes in Railroad Valley are believed to subsist on ground water discharged from nearby regional springs. Ground-water evapotranspiration by the Duckwater phreatophytes of about 11,500 acre-feet estimated by the method described in this report compares well with measured discharge of about 13,500 acre-feet from the springs near Duckwater. Measured discharge from springs near Lockes

  17. Ground Water in the Anchorage Area, Alaska--Meeting the Challenges of Ground-Water Sustainability

    USGS Publications Warehouse

    Moran, Edward H.; Galloway, Devin L.

    2006-01-01

    Ground water is an important component of Anchorage's water supply. During the 1970s and early 80s when ground water extracted from aquifers near Ship Creek was the principal source of supply, area-wide declines in ground-water levels resulted in near record low streamflows in Ship Creek. Since the importation of Eklutna Lake water in the late 1980s, ground-water use has been reduced and ground water has contributed 14-30 percent of the annual supply. As Anchorage grows, given the current constraints on the Eklutna Lake water availability, the increasing demand for water could place an increasing reliance on local ground-water resources. The sustainability of Anchorage's ground-water resources challenges stakeholders to develop a comprehensive water-resources management strategy.

  18. Submarine ground-water discharge: nutrient loading and nitrogen transformations

    USGS Publications Warehouse

    Kroeger, Kevin D.; Swarzenski, Peter W.; Crusius, John; Bratton, John F.; Charette, Matthew A.

    2006-01-01

    Eutrophication of coastal waters due to nonpoint source land-derived nitrogen (N) loads is a worldwide phenomenon and perhaps the greatest agent of change altering coastal ecology (National Research Council, 2000; Howarth and others, 2000). Within the United States, a majority of estuaries have been determined to be moderately to severely impaired by eutrophication associated with increasing nutrient loads (Bricker and others, 1999). In coastal watersheds with soils of high hydraulic conductivity and permeable coastal sediments, ground water is a major route of transport of freshwater and its solutes from land to sea. Freshwater flowing downgradient from aquifers may either discharge from a seepage face near the intertidal zone, or flow directly into the sea as submarine ground-water discharge (SGD) (fig. 1). In the coastal aquifer, entrainment of saline pore water occurs prior to discharge, producing a gradient in ground-water salinity from land to sea, referred to as a subterranean estuary (Moore, 1999). In addition, processes including density-driven flow and tidal pumping create brackish and saline ground-water circulation. Hence, submarine ground-water discharge often consists of a substantial amount of recirculating seawater. Mixing of fresh and saline ground waters in the context of coastal sediments may alter the chemical composition of the discharging fluid. Depending on the biogeochemical setting, removal of fixed N due to processes leading to N2 (dinitrogen gas) production in the nearshore aquifer and subterranean estuary may significantly attenuate land-derived N loads; or, processes such as ion exchange and tidal pumping in the subterranean estuary may substantially accelerate the transport of both land-derived and sediment re-mineralized N to estuarine water columns. As emphasized by Burnett and others (2001, 2002), a fundamental problem in evaluating the importance of ground-water discharge in marine geochemical budgets is the difficulty of

  19. Identifying the hotspots of non-renewable water use using HiGW-MAT: A new land surface model coupled with human interventions and ground water reservoir

    NASA Astrophysics Data System (ADS)

    Oki, T.; Pokhrel, Y. N.; Yeh, P. J.; Koirala, S.; Kanae, S.; Hanasaki, N.

    2011-12-01

    The real hydrological cycles on the Earth are not natural anymore. Global hydrological model simulations of the water cycle and available water resources should have an ability to consider the effects of human interventions on hydrological cycles. Anthropogenic activity modules (Hanasaki et al., 2008), such as reservoir operation, crop growth and water demand in crop lands, and environmental flows, were incorporated into a land surface model called MATSIRO (Takata et al., 2003), to form a new model, MAT-HI (Pokhrel et al., 2011). Total terrestrial water storages (TWS) in large river basins were estimated using the new model by off-line simulation, and compared with the TWS observed by GRACE for 2002-2007. The results showed MAT-HI has an advantage estimating TWS particularly in arid river basins compared with H08 (Hanasaki et al., 2008). MAT-HI was further coupled with a module representing the ground water level fluctuations (Yeh et al., 2005), and consists a new land surface scheme HiGW-MAT (Human Intervention and Ground Water coupled MATSIRO). HiGW-MAT is also associated with a scheme tracing the origin and flow path with the consideration on the sources of water withdrawal from stream flow, medium-size reservoirs and nonrenewable groundwater in addition to precipitation to croplands enabled the assessment of the origin of water producing major crops as Hanasaki et al. (2010). Areas highly dependent on nonrenewable groundwater are detected in the Pakistan, Bangladesh, western part of India, north and western parts of China, some regions in the Arabian Peninsula and the western part of the United States through Mexico. Cumulative nonrenewable groundwater withdrawals estimated by the model are corresponding fairly well with the country statistics of total groundwater withdrawals. Ground water table depletions in large aquifers in US estimated by HiGW-MAT were compared with in-situ observational data, and the correspondences are very good. Mean global exploitation

  20. Ground-water program in Alabama

    USGS Publications Warehouse

    LaMoreaux, P.E.

    1955-01-01

    Several recent years of drought have emphasized the importance of Alabama's ground-water supplies, a matter of concern to us all.  So far we have been blessed in Alabama with ample ground-water, although a combination of increased use, waste, pollution, and drought has brought about critical local water shortages.  These problems serve as a fair warning of what lies ahead if we do not take the necessary steps to obtan adequate knowledge of our ground-water resources.

  1. Ground-Water Protection and Monitoring Program

    SciTech Connect

    Dresel, P.E.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the ground-water protection and monitoring program strategy for the Hanford Site in 1994. Two of the key elements of this strategy are to (1) protect the unconfined aquifer from further contamination, and (2) conduct a monitoring program to provide early warning when contamination of ground water does occur. The monitoring program at Hanford is designed to document the distribution and movement of existing ground-water contamination and provides a historical baseline for evaluating current and future risk from exposure to the contamination and for deciding on remedial action options.

  2. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Maybell, Colorado

    SciTech Connect

    1995-09-01

    The US Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, radioactive contaminated soil, building foundations, and materials associated with the former processing of uranium ore at UMTRA sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to prevent further contamination of ground water. One UMTRA Project site is near Maybell, Colorado. Surface cleanup at this site is under way and is scheduled for completion in 1996. The tailings are being stabilized in-place at this site. The disposal area has been withdrawn from public use by the DOE and is referred to as the permanent withdrawal area. The Ground Water Project evaluates the nature and extent of ground water contamination resulting from past uranium ore processing activities. The Ground Water Project at this site is in its beginning stages. This report is a site-specific document that will be used to evaluate current and future potential impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will determine whether any action is needed to protect human health or the environment. Currently, no points of exposure (e.g. a drinking water well); and no receptors of contaminated ground water have been identified at the Maybell site. Therefore, there are no current human health and ecological risks associated with exposure to contaminated ground water. Furthermore, if current site conditions and land- and water-use patterns do not change, it is unlikely that contaminated ground water would reach people or the ecological communities in the future.

  3. Ground-water hydrology of the Punjab region of West Pakistan, with emphasis on problems caused by canal irrigation

    USGS Publications Warehouse

    Greenman, D.W.; Swarzenski, W.V.; Bennett, G.D.

    1967-01-01

    that the scientific management of this ground-water reservoir is the key to permanent irrigation agriculture in the Punjab. The West Pakistan Water .and Power Development Authority has prepared a long-range program for reclaiming the irrigated lands of the Punjab. The essential feature of this program is a proposed network of tubewells (drilled wells) located with an .average density of about one per square mile. Groundwater withdrawals will serve the dual purpose of helping to supply irrigation requirements and of providing subsurface drainage. Despite the feasibility and inherent advantages of tubewell reclamation methods, it is inevitable that just as the superposition of the canal system on the native environment caused undesirable side effects, large-scale ground-water withdrawals again will disturb the hydrologic regimen. The distribtution of withdrawals and maintenance of a favorable salt balance are two distinct, but related aspects of the ground-water budget that present potential hazards that must be considered in the design and management of the tubewell projects. The availability of ground water for irrigation diminishes from northeast to southwest, or downgradient along the doab (an area lying between two rivers) and is negligible in the centers of the lower parts of the doabs, where the ground water is too highly mineralized for use. Ground-water supplies must be developed in areas where they are available and it might become necessary, under a program of maximum exploitation of ground-water resources, to transfer supplies from outside sources to points of use in the lower parts of the doabs. Several factors inherent in the tubewell system will tend to depreciate the quality of ground water with time. Among these are the addition of salts leached from the soils, increased concentration of salts due .to repeated cycles of recirculation, and the possible lateral and upward encroachment of saline water in response to pumping. It is reasonably ce

  4. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of:...

  5. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of:...

  6. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of:...

  7. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of:...

  8. Ground-water models cannot be validated

    USGS Publications Warehouse

    Konikow, L.F.; Bredehoeft, J.D.

    1992-01-01

    Ground-water models are embodiments of scientific hypotheses. As such, the models cannot be proven or validated, but only tested and invalidated. However, model testing and the evaluation of predictive errors lead to improved models and a better understanding of the problem at hand. In applying ground-water models to field problems, errors arise from conceptual deficiencies, numerical errors, and inadequate parameter estimation. Case histories of model applications to the Dakota Aquifer, South Dakota, to bedded salts in New Mexico, and to the upper Coachella Valley, California, illustrate that calibration produces a nonunique solution and that validation, per se, is a futile objective. Although models are definitely valuable tools for analyzing ground-water systems, their predictive accuracy is limited. The terms validation and verification are misleading and their use in ground-water science should be abandoned in favor of more meaningful model-assessment descriptors. ?? 1992.

  9. Pollution of ground water in Europe

    PubMed Central

    Buchan, S.; Key, A.

    1956-01-01

    This paper discusses pollution of ground water in 20 countries of the European region, giving for each an account of the geology and hydrogeology, water supplies, the extent and nature of ground water pollution, and the legal, administrative, and technical means of controlling that pollution. For the countries not considered in the preceding article on surface water pollution, an account is also given of the superficial physical features, rainfall, population, and industries. A general discussion follows of such questions as the ways in which ground water pollution may occur, the factors mitigating or aggravating pollution, and ways of protection against pollution. The authors consider that the problem of ground water pollution in Europe may well be more serious than it would appear to be on the evidence so far obtained. PMID:13374533

  10. GROUND WATER CONTAMINATION POTENTIAL FROM STORMWATER INFILTRATION

    EPA Science Inventory

    Prior to urbanization, ground water recharge resulted from infiltration of precipitation through pervious surfaces, including grasslands and woods. This infiltration water was relatively uncontaminated. With urbanization, the permeable soil surface area through which recharge by...

  11. Hydrogeology and ground-water flow in the Edwards-Trinity aquifer-system, west-central, Texas

    USGS Publications Warehouse

    Kuniansky, E.L.; Ardis, A.F.

    1997-01-01

    Comparison of pre- and postdevelopment water budgets for the regional model indicates that the increase in groundwater withdrawals has captured 20 percent of the water that would have naturally discharged to streams, and 30 percent of the natural discharge to springs after ground-water development. Induced recharge from streams to the ground-water system increased by 12 percent in the postdevelopment simulation compared to the predevelopment simulation.

  12. Selected Ground-Water Data for Yucca Mountain Region, Southern Nevada and Eastern California, January-December 2004

    USGS Publications Warehouse

    La Camera, Richard J.; Locke, Glenn L.; Habte, Aron M.; Darnell, Jon G.

    2006-01-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Office of Repository Development, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region of southern Nevada and eastern California. These data are collected to allow assessments of ground-water resources during activities to determine the potential suitability or development of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 35 boreholes and 1 fissure (Devils Hole), ground-water discharge at 5 springs, both ground-water levels and discharge at 1 flowing borehole, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are tabulated from January through December 2004. Also tabulated are ground-water levels, discharges, and withdrawals collected by other agencies (or collected as part of other programs) and data revised from those previously published at monitoring sites. Historical data on water levels, discharges, and withdrawals are presented graphically to indicate variations through time. A statistical summary of ground-water levels at seven boreholes in Jackass Flats is presented for the period 1992-2004 to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the annual number of measurements, maximum, minimum, and median water-level altitudes, and average deviation of measured water-level altitudes compared to the 1992-93 baseline period. At six boreholes in Jackass Flats, median water levels for 2004 were slightly higher (0.3-2.7 feet) than their median water levels for 1992-93. At one borehole in Jackass Flats, median water level for 2004 equaled the median water level for 1992-93.

  13. Estimated freshwater withdrawals in Texas, 1990

    USGS Publications Warehouse

    Lurry, Dee L.

    1994-01-01

    This report presents 1990 freshwater withdrawal estimates for Texas by source and category. Withdrawal source is either ground water or surface water. Withdrawal categories include: self-supplied irrigation, thermoelectric-power generation, water supply, industrial and mining, and other (domestic, commercial, livestock). Withdrawal data are aggregated by county, major aquifer, and principal river basin. Only the four major categories of irrigation, thermoelectric-power generation, water supply, and industrial and mining are illustrated in this report, although all data are tabulated.

  14. Methods and Indicators for Assessment of Regional Ground-Water Conditions in the Southwestern United States

    USGS Publications Warehouse

    Tillman, Fred D; Leake, Stanley A.; Flynn, Marilyn E.; Cordova, Jeffrey T.; Schonauer, Kurt T.; Dickinson, Jesse E.

    2008-01-01

    Monitoring the status and trends in the availability of the Nation's ground-water supplies is important to scientists, planners, water managers, and the general public. This is especially true in the semiarid to arid southwestern United States where rapid population growth and limited surface-water resources have led to increased use of ground-water supplies and water-level declines of several hundred feet in many aquifers. Individual well observations may only represent aquifer conditions in a limited area, and wells may be screened over single or multiple aquifers, further complicating single-well interpretations. Additionally, changes in ground-water conditions may involve time scales ranging from days to many decades, depending on the timing of recharge, soil and aquifer properties, and depth to the water table. The lack of an easily identifiable ground-water property indicative of current conditions, combined with differing time scales of water-level changes, makes the presentation of ground-water conditions a difficult task, particularly on a regional basis. One approach is to spatially present several indicators of ground-water conditions that address different time scales and attributes of the aquifer systems. This report describes several methods and indicators for presenting differing aspects of ground-water conditions using water-level observations in existing data-sets. The indicators of ground-water conditions developed in this study include areas experiencing water-level decline and water-level rise, recent trends in ground-water levels, and current depth to ground water. The computer programs written to create these indicators of ground-water conditions and display them in an interactive geographic information systems (GIS) format are explained and results illustrated through analyses of ground-water conditions for selected alluvial basins in the Lower Colorado River Basin in Arizona.

  15. Ground-water quality in Wyoming

    USGS Publications Warehouse

    Larson, L.R.

    1984-01-01

    This report graphically summarizes ground-water quality from selected chemical-quality data for about 2,300 ground-water sites in Wyoming. Dissolved-solids, nitrate, fluoride, arsenic, barium, cadmium, chromium, lead, mercury, selenium, iron, and manganese concentrations are summarized on a statewide basis. The major chemical-quality problem that limits the use of Wyoming ground-water is excessive dissolved-solids concentrations. The aquifers with the best quality water, based on the lowest median dissolved-solids concentration of water in aquifers with 20 or more sampled sites, are Holocene lacustrine deposits, the upper Testiary Ogallala Formation and Arikaree Formation, and the Mississippian Madison Limestone. The counties with the best quality water, based on the lowest median dissolved-solids concentrations are Teton County and Laramie County. Hot Springs County and Natrona County have the highest median dissolved-solids concentrations. About 3 percent of the nitrate concentrations of ground-water samples exceeded the national primary drinking-water standard of 10 milligrams per liter. Fluoride concentrations exceeded the national primary drinking-water standard in 14 percent of the ground-water samples. Except for selenium, toxic trace elements generally have not been found in concentrations in excess of the drinking-water standards. About 19 percent of the iron and about 30 percent of the manganese concentrations in ground-water samples exceeded the national secondary drinking-water standards. (USGS)

  16. Estimating ground water discharge by hydrograph separation.

    PubMed

    Hannula, Steven R; Esposito, Kenneth J; Chermak, John A; Runnells, Donald D; Keith, David C; Hall, Larry E

    2003-01-01

    Iron Mountain is located in the West Shasta Mining District in California. An investigation of the generation of acid rock drainage and metals loading to Boulder Creek at Iron Mountain was conducted. As part of that investigation, a hydrograph separation technique was used to determine the contribution of ground water to total flow in Boulder Creek. During high-flow storm events in the winter months, peak flow in Boulder Creek can exceed 22.7 m3/sec, and comprises surface runoff, interflow, and ground water discharge. A hydrograph separation technique was used to estimate ground water discharge into Boulder Creek during high-flow conditions. Total ground water discharge to the creek approaches 0.31 m3/sec during the high-flow season. The hydrograph separation technique combined with an extensive field data set provided reasonable estimates of ground water discharge. These estimates are useful for other investigations, such as determining a corresponding metals load from the metal-rich ground water found at Iron Mountain and thus contributing to remedial alternatives. PMID:12772830

  17. Ground-Water Quality Data in the Monterey Bay and Salinas Valley Basins, California, 2005 - Results from the California GAMA Program

    USGS Publications Warehouse

    Kulongoski, Justin T.; Belitz, Kenneth

    2007-01-01

    Ground-water quality in the approximately 1,000-square-mile Monterey Bay and Salinas Valley study unit was investigated from July through October 2005 as part of the California Ground-Water Ambient Monitoring and Assessment (GAMA) program. The study was designed to provide a spatially unbiased assessment of raw ground-water quality, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 94 public-supply wells and 3 monitoring wells in Monterey, Santa Cruz, and San Luis Obispo Counties. Ninety-one of the public-supply wells sampled were selected to provide a spatially distributed, randomized monitoring network for statistical representation of the study area. Six wells were sampled to evaluate changes in water chemistry: three wells along a ground-water flow path were sampled to evaluate lateral changes, and three wells at discrete depths from land surface were sampled to evaluate changes in water chemistry with depth from land surface. The ground-water samples were analyzed for volatile organic compounds (VOCs), pesticides, pesticide degradates, nutrients, major and minor ions, trace elements, radioactivity, microbial indicators, and dissolved noble gases (the last in collaboration with Lawrence Livermore National Laboratory). Naturally occurring isotopes (tritium, carbon-14, helium-4, and the isotopic composition of oxygen and hydrogen) also were measured to help identify the source and age of the sampled ground water. In total, 270 constituents and water-quality indicators were investigated for this study. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, and (or) blended with other waters to maintain water quality. In addition, regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. In this study, only six constituents, alpha radioactivity, N

  18. Summary appraisals of the Nation's ground-water resources; Texas-Gulf region

    USGS Publications Warehouse

    Baker, E.T.; Wall, J.R.

    1976-01-01

    Because significant amounts of ground water are available, the opportunities for expanded and conjunctive use of ground water and surface water should be considered in regional plans for water development and conservation. The complexities of water management and the difficulties of achieving an integrated system of total-water management will require additional technical information.

  19. Summary appraisals of the Nation's ground-water resources; Texas Gulf region

    USGS Publications Warehouse

    Baker, E.T.; Wall, James Ray

    1974-01-01

    Because significant amounts of ground water are available, the opportunities for expanded and conjunctive use of ground water and surface water should be considered in regional plans for water development and conservation. The complexities of water management and the difficulties of achieving an integrated system of total water management will require additional technical information.

  20. Ground-water availability from surficial aquifers in the Red River of the North Basin, Minnesota

    USGS Publications Warehouse

    Reppe, Thomas H.C.

    2005-01-01

    On the basis of data and methods presented to evaluate ground-water availability, the Otter Tail and Pineland Sands surficial aquifers and Pelican River sand-plain aquifer have the greatest potential for additional development of ground-water resources in the study area.

  1. 40 CFR 141.405 - Reporting and recordkeeping for ground water systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... water systems. 141.405 Section 141.405 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.405 Reporting and recordkeeping for ground water systems. (a) Reporting. In addition to...

  2. 40 CFR 141.405 - Reporting and recordkeeping for ground water systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... water systems. 141.405 Section 141.405 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.405 Reporting and recordkeeping for ground water systems. (a) Reporting. In addition to...

  3. 40 CFR 141.405 - Reporting and recordkeeping for ground water systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... water systems. 141.405 Section 141.405 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.405 Reporting and recordkeeping for ground water systems. (a) Reporting. In addition to...

  4. 40 CFR 141.405 - Reporting and recordkeeping for ground water systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... water systems. 141.405 Section 141.405 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.405 Reporting and recordkeeping for ground water systems. (a) Reporting. In addition to...

  5. MICROBIAL RESPONSES TO CHEMICAL OXIDATION, SIX-PHASE HEATING, AND STEAM INJECTION TREATMENT IN GROUND WATER

    EPA Science Inventory

    MTBE (methyl tertiary butyl ether) is present at high concentrations in ground water at many sites where gasoline has been spilled from underground storage tanks. In addition, TBA (tertiary butyl alcohol) is also present at high concentrations in many of the same ground waters. ...

  6. An appraisal of ground water for irrigation in the Appleton area, west-central Minnesota

    USGS Publications Warehouse

    Larson, Steven P.

    1976-01-01

    Mathematical models of a part of the aquifer were made to evaluate the effects of 20 successive years of ground-water withdrawal for three irrigation-development patterns. It was estimated that the present annual withdrawal rate of 1,410 acre-ft (1.74 hm3) would result in water-level declines of less than 3 feet (0.9 m). However, annual withdrawals of 8,450 acre-ft (10.4 hm3) would cause aquifer dewatering and decreased well yields in some places. After a new state of equilibrium was established in response to withdrawals, most of the withdrawal would be supplied by diverted base flow from the Pomme de Terre River.

  7. Studies examine contaminants: Pharmaceuticals, hormones and other organic wastewater contaminants in ground water resources

    USGS Publications Warehouse

    Barnes, Kymm K.; Kolpin, Dana W.; Furlong, Edward T.; Zaugg, Steven D.; Meyer, Michael T.; Barber, Larry B.; Focazio, Michael J.

    2005-01-01

    Ground water provides approximately 40 percent of the nation’s public water supply, and the total percentage of withdrawals for irrigation has increased from 23 percent in 1950 to 42 percent in 2000. Ground water also is a major contributor to flow in many streams and rivers in the United States and has a substantial influence on river and wetland habitats for plants and animals. Organic wastewater contaminants (OWCs) in the environment recently have been documented to be of global concern with a variety of sources and source pathways.

  8. The role of ground water in generating streamflow in headwater areas and in maintaining base flow

    USGS Publications Warehouse

    Winter, T.C.

    2007-01-01

    The volume and sustainability of streamflow from headwaters to downstream reaches commonly depend on contributions from ground water. Streams that begin in extensive aquifers generally have a stable point of origin and substantial discharge in their headwaters. In contrast, streams that begin as discharge from rocks or sediments having low permeability have a point of origin that moves up and down the channel seasonally, have small incipient discharge, and commonly go dry. Nearly all streams need to have some contribution from ground water in order to provide reliable habitat for aquatic organisms. Natural processes and human activities can have a substantial effect on the flow of streams between their headwaters and downstream reaches. Streams lose water to ground water when and where their head is higher than the contiguous water table. Although very common in arid regions, loss of stream water to ground water also is relatively common in humid regions. Evaporation, as well as transpiration from riparian vegetation, causing ground-water levels to decline also can cause loss of stream water. Human withdrawal of ground water commonly causes streamflow to decline, and in some regions has caused streams to cease flowing. ?? 2007 American Water Resources Association.

  9. Simulation of ground-water flow in the Intermediate and Floridan aquifer systems in Peninsular Florida

    USGS Publications Warehouse

    Sepulveda, Nicasio

    2002-01-01

    A numerical model of the intermediate and Floridan aquifer systems in peninsular Florida was used to (1) test and refine the conceptual understanding of the regional ground-water flow system; (2) develop a data base to support subregional ground-water flow modeling; and (3) evaluate effects of projected 2020 ground-water withdrawals on ground-water levels. The four-layer model was based on the computer code MODFLOW-96, developed by the U.S. Geological Survey. The top layer consists of specified-head cells simulating the surficial aquifer system as a source-sink layer. The second layer simulates the intermediate aquifer system in southwest Florida and the intermediate confining unit where it is present. The third and fourth layers simulate the Upper and Lower Floridan aquifers, respectively. Steady-state ground-water flow conditions were approximated for time-averaged hydrologic conditions from August 1993 through July 1994 (1993-94). This period was selected based on data from Upper Floridan a quifer wells equipped with continuous water-level recorders. The grid used for the ground-water flow model was uniform and composed of square 5,000-foot cells, with 210 columns and 300 rows.

  10. Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Maybell, Colorado

    SciTech Connect

    1996-03-01

    The U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, contaminated soil, building foundations, and materials associated with the former processing of uranium ore at UMTRA Project sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to prevent further contamination of ground water. One UMTRA Project site is near Maybell, Colorado. Surface cleanup at this site began in 1995 and is scheduled for completion in 1996. The tailings are being stabilized in place at this site. The disposal area has been withdrawn from public use by the DOE and is referred to as the permanent withdrawal area. The Ground Water Project evaluates the nature and extent of ground water contamination resulting from past uranium ore processing activities. The Ground Water Project at this site is in its beginning stages. This report is a site-specific document that will be used to evaluate current and future potential impacts to the public and the environment from exposure to contaminated ground water. The results presented in this document and other evaluations will determine whether any action is needed to protect human health or the environment.

  11. Effects of irrigation pumping on the ground-water system in Newton and Jasper Counties, Indiana

    USGS Publications Warehouse

    Bergeron, Marcel P.

    1981-01-01

    Flow in the ground-water system in Newton and Jasper Counties, Indiana, was simulated in a quasi-three-dimensional model in a study of irrigation use of ground water in the two counties. The ground-water system consists of three aquifers: (1) a surficial coarse sand aquifer known as the Kankakee aquifer, (2) a limestone and dolomite bedrock aquifer, and (3) a sand and gravel bedrock valley aquifer. Irrigation pumping, derived primarily from the bedrock, was estimated to be 34.8 million gallons per day during peak irrigation in 1977. Acreage irrigated with ground water is estimated to be 6,200 acres. A series of model experiments was used to estimate the effects of irrigation pumping on ground-water levels and streamflow. Model analysis indicates that a major factor controlling drawdown due to pumping in the bedrock aquifer are the variations in thickness and in vertical hydraulic conductivity in a semiconfining unit overlying the bedrock. Streamflow was not significantly reduced by hypothetical withdrawals of 12.6 million gallons per day from the bedrock aquifer and 10.3 million gallons per day in the Kankakee aquifer. Simulation of water-level recovery after irrigation pumping indicated that a 5-year period of alternating between increasing pumping and recovery will not cause serious problems of residual drawdown or ground-water mining. 

  12. Hydrogeology and quality of ground water in the upper Arkansas River basin from Buena Vista to Salida, Colorado, 2000-2003

    USGS Publications Warehouse

    Watts, Kenneth R.

    2005-01-01

    The upper Arkansas River Basin between Buena Vista and Salida, Colorado, is a downfaulted basin, the Buena Vista-Salida structural basin, located between the Sawatch and Mosquito Ranges. The primary aquifers in the Buena Vista-Salida structural basin consist of poorly consolidated to unconsolidated Quaternary-age alluvial and glacial deposits and Tertiary-age basin-fill deposits. Maximum thickness of the alluvial, glacial, and basin-fill deposits is about 5,000 feet, but 95 percent of the water-supply wells in Chaffee County are no more than 300 feet deep. Hydrologic conditions in the 149-square mile study area are described on the basis of hydrologic and geologic data compiled and collected during September 2000 through September 2003. The principal aquifers described in this report are the alluvial-outwash and basin-fill aquifers. An estimated 3,443 wells pumped about 690 to 1,240 acre-feet for domestic and household use in Chaffee County during 2003. By 2030, projected increases in the population of Chaffee County, Colorado, may require use of an additional 4,000 to 5,000 wells to supply an additional 800 to 1,800 acre-feet per year of ground water for domestic and household supply. The estimated specific yield of the upper 300 feet of the alluvial-outwash and basin-fill aquifers ranged from about 0.02 to 0.2. Current (2003) and projected (2030) ground-water withdrawals by domestic and household wells are less than 1 percent of the estimated 472,000 acre-feet of drainable ground water in the upper 300 feet of the subsurface. Locally, little water is available in the upper 300 feet. In densely populated areas, well interference could result in decreased water levels and well yields, which may require deepening or replacement of wells. Infiltration of surface water diverted for irrigation and from losing streams is the primary source of ground-water recharge in the semiarid basin. Ground-water levels in the alluvial-outwash and basin-fill aquifers vary seasonally

  13. Chemical quality of ground water on Cape Cod, Massachusetts

    USGS Publications Warehouse

    Frimpter, M.H.; Gay, F.B.

    1979-01-01

    Cape Cod is a 440 square mile hook-shaped peninsula which extends 40 miles into the Atlantic. Freshwater in Pleistocene sand and gravel deposits is the source of supply for nearly 100 municipal and thousands of private domestic wells. Most ground water on Cape Cod is of good chemical quality for drinking and other uses. It is characteristically low in dissolved solids and is soft. In 90 percent of the samples analyzed, dissolved solids were less than 100 mg/l (milligrams per liter) and pH was less than 7.0. Highway deicing salt, sea-water flooding due to storms , and saltwater intrusion due to ground-water withdrawal are sources of sodium chloride contamination. Chloride concentrations have increased from 20 to 140 mg/l, owing to saltwater intrusion at Provincetown 's wells in Truro. In Yarmouth, contaminated ground water near a salt-storage area contained as much as 1,800 mg/l chloride. Heavy metals, insecticides, and herbicides were not found at concentrations above the U.S. Environmental Protection Agency 's recommended limits for public drinking-water supplies, but iron and manganese in some samples exceeded those limits. Ninety percent of 84 samples analyzed for nitrate reported as nitrogen contained less than 1.3 mg/l and 80 percent contained 0.5 mg/l or less of nitrate as nitrogen. Water containing nitrogen in excess of 0.5 mg/l has probably been affected by municipal or domestic sewage or fertilizer, and water with less than this amount may have been affected by them. (Woodard-USGS)

  14. Simulated water budgets and ground-water/surface-water interactions in Bushkill and parts of Monocacy Creek watersheds, Northampton County, Pennsylvania--a preliminary study with identification of data needs

    USGS Publications Warehouse

    Risser, Dennis W.

    2006-01-01

    This report, prepared in cooperation with the Department of Environmental Protection, Office of Mineral Resources Management, provides a preliminary analysis of water budgets and generalized ground-water/surface-water interactions for Bushkill and parts of Monocacy Creek watersheds in Northampton County, Pa., by use of a ground-water flow model. Bushkill Creek watershed was selected for study because it has areas of rapid growth, ground-water withdrawals from a quarry, and proposed stream-channel modifications, all of which have the potential for altering ground-water budgets and the interaction between ground water and streams. Preliminary 2-dimensional, steady-state simulations of ground-water flow by the use of MODFLOW are presented to show the status of work through September 2005 and help guide ongoing data collection in Bushkill Creek watershed. Simulations were conducted for (1) predevelopment conditions, (2) a water table lowered for quarry operations, and (3) anthropogenic changes in hydraulic conductivity of the streambed and aquifer. Preliminary results indicated under predevelopment conditions, the divide between the Bushkill and Monocacy Creek ground-water basins may not have been coincident with the topographic divide and as much as 14 percent of the ground-water discharge to Bushkill Creek may have originated from recharge in the Monocacy Creek watershed. For simulated predevelopment conditions, Schoeneck Creek and parts of Monocacy Creek were dry, but Bushkill Creek was gaining throughout all reaches. Simulated lowering of the deepest quarry sump to an altitude of 147 feet for quarry operations caused ground-water recharge and streamflow leakage to be diverted to the quarry throughout about 14 square miles and caused reaches of Bushkill and Little Bushkill Creeks to change from gaining to losing streams. Lowering the deepest quarry sump to an altitude of 100 feet caused simulated ground-water discharge to the quarry to increase about 4 cubic feet

  15. MODFLOW-2000, The U.S. Geological Survey Modular Ground-Water Model - User Guide to Modularization Concepts and the Ground-Water Flow Process

    USGS Publications Warehouse

    Harbaugh, Arlen W.; Banta, Edward R.; Hill, Mary C.; McDonald, Michael G.

    2000-01-01

    MODFLOW is a computer program that numerically solves the three-dimensional ground-water flow equation for a porous medium by using a finite-difference method. Although MODFLOW was designed to be easily enhanced, the design was oriented toward additions to the ground-water flow equation. Frequently there is a need to solve additional equations; for example, transport equations and equations for estimating parameter values that produce the closest match between model-calculated heads and flows and measured values. This report documents a new version of MODFLOW, called MODFLOW-2000, which is designed to accommodate the solution of equations in addition to the ground-water flow equation. This report is a user's manual. It contains an overview of the old and added design concepts, documents one new package, and contains input instructions for using the model to solve the ground-water flow equation.

  16. Ground-water contamination and legal controls in Michigan

    USGS Publications Warehouse

    Deutsch, Morris

    1963-01-01

    The great importance of the fresh ground-water resources of Michigan is evident because 90 percent of the rural and about 70 percent of the total population of the State exclusive of the Detroit metropolitan area are supplied from underground sources. The water-supply and public-health problems that have been caused by some cases of ground-water contamination in the State illustrate the necessity of protecting this vital resource.Manmade and natural contaminants, including many types of chemical and organic matter, have entered many of the numerous aquifers of the State. Aquifers have been contaminated by waste-laden liquids percolating from the surface or from the zone of aeration and by direct injection to the aquifer itself. Industrial and domestic wastes, septic tanks, leaking sewers, flood waters or other poor quality surface waters, mine waters, solids stored or spread at the surface, and even airborne wastes all have been sources of ground-water contamination in Michigan. In addition, naturally occurring saline waters have been induced into other aquifers by overpumping or unrestricted flow from artesian wells, possibly by dewatering operations, and by the deepening of surface stream channels. Vertical migration of saline waters through open holes from formations underlying various important aquifers also has spoiled some of the fresh ground waters in the State. In spite of the contamination that has occurred, however, the total amount of ground water that has been spoiled is only a small part of the total resource. Neither is the contamination so widespread as that of the surface streams of Michigan.Overall legal authority to control most types of ground-water contamination in the State has been assigned by the Michigan Legislature to the Water Resources Commission, although the Department of Conservation and the Health Department also exercise important water-pollution control functions. The Michigan Supreme Court, in an important case upholding the power

  17. Nitrate behavior in ground waters of the southeastern USA

    USGS Publications Warehouse

    Nolan, B.T.

    1999-01-01

    Principal components analysis (PCA) was performed with water-quality data from studies conducted during 1993 to 1995 to explore potential nitrate- attenuation processes in ground waters of the southeastern USA. Nitrate reduction is an important attenuation process in selected areas of the Southeast. A nitrate-reduction component explains 23% of the total variance in the data and indicates that nitrate and dissolved oxygen (DO) are inversely related to ammonium, iron, manganese, and dissolved organic carbon (DOC). Additional components extracted by PCA include calcite dissolution (18% of variance explained) and phosphate dissolution (9% of variance explained). Reducing conditions in ground waters of the region influence nitrate behavior through bacterially mediated reduction in the presence of organic matter, and by inhibition of nitrate formation in anoxic ground water beneath forested areas. Component scores are consistent with observed water- quality conditions in the region. For example, median nitrate concentration in ground-water samples from the Albemarle-Pamlico Drainage Basin (ALBE) Coastal Plain is <0.05 mg L-1, median DOC concentration is 4.2 mg L-1, and median DO concentration is 2.1 mg L-1, consistent with denitrification. Nitrate reduction does not occur uniformly throughout the Southeast. Median DO concentrations in ground-water samples from the Apalachicola- Chattahoochee-Flint River Basin (ACFB) are 6.2 to 7.1 mg L-1, and median nitrate concentrations are 0.61 to 2.2 mg L-1, inconsistent with denitrification. Similarly, median DO concentration in samples from the Georgia-Florida Coastal Plain (GAFL) is 6.0 mg L-1 and median nitrate concentration is 5.8 mg L-1.

  18. Nitrate behavior in ground water of the southeastern USA

    SciTech Connect

    Nolan, B.T.

    1999-10-01

    Principal components analysis (PCA) was performed with water-quality data from studies conducted during 1993 to 1995 to explore potential nitrate-attenuation processes in ground waters of the southeastern USA. Nitrate reduction is an important attenuation process in selected areas of the Southeast. A nitrate-reduction component explains 23% of the total variance in the data and indicates that nitrate and dissolved oxygen (DO) are inversely related to ammonium, iron, manganese, and dissolved organic carbon (DOC). Additional components extracted by PCA include calcite dissolution (18% of variance explained) and phosphate dissolution (9% of variance explained). Reducing conditions in ground waters of the region influence nitrate behavior through bacterially mediated reduction in the presence of organic matter, and by inhibition of nitrate formation in anoxic ground water beneath forested areas. Component scores are consistent with observed water-quality conditions in the region. For example, median nitrate concentration in ground-water samples from the Albemarle-Pamlico Drainage Basin (ALBE) Coastal Plain is {lt}0.05 mg L{sup {minus}1}, median DOC concentration is 4.2 mg L{sup {minus}1}, and median DO concentration is 2.1 mg L{sup {minus}1}, consistent with denitrification. Nitrate reduction does not occur uniformly throughout the Southeast. Median DO concentrations in ground-water samples from the Apalachicola-Chattahoochee-Flint River Basin (ACFB) are 6.2 to 7.1 mg L{sup {minus}1}, and median nitrate concentrations are 0.61 to 2.2 mg L{sup {minus}1}, inconsistent with denitrification. Similarly, median DO concentration in samples from the Georgia-Florida Coastal Plain (GAFL) is 6.0 mg L{sup {minus}1} and median nitrate concentration is 5.8 mg L{sup {minus}1}.

  19. Artificial recharge of humic ground water.

    PubMed

    Alborzfar, M; Villumsen, A; Grøn, C

    2001-01-01

    The purpose of this study was to investigate the efficiency of soil in removing natural organic matter from humic ground waters using artificial recharge. The study site, in western Denmark, was a 10,000 ml football field of which 2,000 m2 served as an infiltration field. The impact of the artificial recharge was studied by monitoring the water level and the quality of the underlying shallow aquifer. The humic ground water contained mainly humic adds with an organic carbon (OC) concentration of 100 to 200 mg C L(-1). A total of 5,000 mS of humic ground water were sprinkled onto the infiltration field at an average rate of 4.25 mm h(-1). This resulted in a rise in the water table of the shallow aquifer. The organic matter concentration of the water in the shallow aquifer, however, remained below 2.7 mg C L(-1). The organic matter concentration of the pore water in the unsaturated zone was measured at the end of the experiment. The organic matter concentration of the pore water decreased from 105 mg C L(-1) at 0.5 m to 20 mg C L(-1) at 2.5 m under the infiltration field indicating that the soil removed the organic matter from the humic ground water. From these results we conclude that artificial recharge is a possible method for humic ground water treatment.

  20. Estimated Withdrawals from Stream-Valley Aquifers and Refined Estimated Withdrawals from Selected Aquifers in the United States, 2000

    USGS Publications Warehouse

    Sargent, B. Pierre; Maupin, Molly A.; Hinkle, Stephen R.

    2008-01-01

    The U.S. Geological Survey National Water Use Information Program compiles estimates of fresh ground-water withdrawals in the United States on a 5-year interval. In the year-2000 compilation, withdrawals were reported from principal aquifers and aquifer systems including two general aquifers - Alluvial and Other aquifers. Withdrawals from a widespread aquifer group - stream-valley aquifers - were not specifically identified in the year-2000 compilation, but they are important sources of ground water. Stream-valley aquifers are alluvial aquifers located in the valley of major streams and rivers. Stream-valley aquifers are long but narrow aquifers that are in direct hydraulic connection with associated streams and limited in extent compared to most principal aquifers. Based in large part on information published in U.S. Geological Survey reports, preliminary analysis of withdrawal data and hydrogeologic and surface-water information indicated areas in the United States where possible stream-valley aquifers were located. Further assessment focused on 24 states and the Commonwealth of Puerto Rico. Withdrawals reported from Alluvial aquifers in 16 states and withdrawals reported from Other aquifers in 6 states and the Commonwealth of Puerto Rico were investigated. Two additional States - Arkansas and New Jersey - were investigated because withdrawals reported from other principal aquifers in these two States may be from stream-valley aquifers. Withdrawals from stream-valley aquifers were identified in 20 States and were about 1,560 Mgal/d (million gallons per day), a rate comparable to withdrawals from the 10 most productive principal aquifers in the United States. Of the 1,560 Mgal/d of withdrawals attributed to stream-valley aquifers, 1,240 Mgal/d were disaggregated from Alluvial aquifers, 150 Mgal/d from glacial sand and gravel aquifers, 116 Mgal/d from Other aquifers, 28.1 Mgal/d from Pennsylvanian aquifers, and 24.9 Mgal/d from the Mississippi River Valley alluvial

  1. Water management, agriculture, and ground-water supplies

    USGS Publications Warehouse

    Nace, Raymond L.

    1960-01-01

    Encyclopedic data on world geography strikingly illustrate the drastic inequity in the distribution of the world's water supply. About 97 percent of the total volume of water is in the world's oceans. The area of continents and islands not under icecaps, glaciers, lakes, and inland seas is about 57.5 million square miles, of which 18 million (36 percent) is arid to semiarid. The total world supply of water is about 326.5 million cubic miles, of which about 317 million is in the oceans and about 9.4 million is in the land areas. Atmospheric moisture is equivalent to only about 3,100 cubic miles of water. The available and accessible supply of ground water in the United States is somewhat more than 53,000 cubic miles (about 180 billion acre ft). The amount of fresh water on the land areas of the world at any one time is roughly 30,300 cubic miles and more than a fourth of this is in large fresh-water lakes on the North American Continent. Annual recharge of ground water in the United States may average somewhat more than 1 billion acre-feet yearly, but the total volume of ground water in storage is equivalent to all the recharge in about the last 160 years. This accumulation of ground water is the nation's only reserve water resource, but already it is being withdrawn or mined on a large scale in a few areas. The principal withdrawals of water in the United States are for agriculture and industry. Only 7.4 percent of agricultural land is irrigated, however; so natural soil moisture is the principal source of agricultural water, and on that basis agriculture is incomparably the largest water user. In view of current forecasts of population and industrial expansion, new commitments of water for agriculture should be scrutinized very closely, and thorough justification should be required. The 17 Western States no longer contain all the large irrigation developments. Nearly 10 percent of the irrigated area is in States east of the western bloc, chiefly in several

  2. Montana's Coalbed Methane Ground-Water Monitoring Program: Year One

    NASA Astrophysics Data System (ADS)

    Wheaton, J. R.; Smith, M.; Donato, T. A.; Bobst, A. L.

    2003-12-01

    specifically for the CBM program and 72 existing wells from the coal-mine hydrogeology program. Additionally, drilling of about 25 more wells is in the planning stage. About 20 springs are being monitored specific to CBM. At all sites both water-quantity data (regular water levels, one-time aquifer testing, flow rates at springs) and water-quality data (field parameters or laboratory samples for major and minor constituents) are being collected. Monitoring locations and specific monitoring activities will continue to be adjusted in response to CBM development and data needs. All data collected as part of this program are made immediately available to the public on the Internet through the Montana Ground-Water Information Center (http://mbmggwic.mtech.edu/). Interpretive reports based on data collected will be published under standard scientific protocols. Data and reports will be used by industry, landowners, regulators and researchers in assessing impacts, lack of impacts and recovery of ground-water systems in relation to production of coalbed methane. Funding for this program has been provided by the U. S. Bureau of Land Management, U. S. Forest Service, U. S. Environmental Protection Agency, local Conservation Districts and the State of Montana. Coalbed methane production and consequent impacts to ground-water in this semi-arid region are controversial. Acceptance by all parties of data and interpretations resulting from the CBM monitoring program is enhanced by the credibility established through the more than 30-year history of the coal-mine hydrogeology program.

  3. Ground-water quality atlas of Wisconsin

    USGS Publications Warehouse

    Kammerer, Phil A.

    1981-01-01

    This report summarizes data on ground-water quality stored in the U.S. Geological Survey's computer system (WATSTORE). The summary includes water quality data for 2,443 single-aquifer wells, which tap one of the State's three major aquifers (sand and gravel, Silurian dolomite, and sandstone). Data for dissolved solids, hardness, alkalinity, calcium, magnesium, sodium, potassium, iron, manganese, sulfate, chloride, fluoride, and nitrate are summarized by aquifer and by county, and locations of wells for which data are available 1 are shown for each aquifer. Calcium, magnesium, and bicarbonate (the principal component of alkalinity) are the major dissolved constituents in Wisconsin's ground water. High iron concentrations and hardness cause ground-water quality problems in much of the State. Statewide ,summaries of trace constituent (selected trace metals; arsenic, boron, and organic carbon) concentrations show that these constituents impair water quality in only a few isolated wells.

  4. Ground-water conditions in Georgia, 2000

    USGS Publications Warehouse

    Cressler, A.M.; Blackburn, D.K.; McSwain, K.B.

    2001-01-01

    Ground-water conditions in Georgia during 1999 and for the period of record were evaluated using data from U.S. Geological Survey ground-water-level and ground-water-quality monitoring networks. Data for 1999 included in this report are from continuous water-level records from 130 wells and chloride analyses from 14 wells. Data from one well is incomplete because data collection was discontinued. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standards.

  5. Ground-water conditions in Georgia, 1998

    USGS Publications Warehouse

    Cressler, Alan M.

    1999-01-01

    Ground-water conditions in Georgia during 1998 and for the period of record were evaluated using data from U.S. Geological Survey ground-water-level and ground-water-quality monitoring networks. Data for 1998 included in this report are from continuous water-level records from 130 wells and chloride analyses from 14 wells. Data from one well is incomplete because data collection was discontinued. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was within drinking-water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency. In the Savannah area, chloride concentration has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking-water standards.

  6. EPA GROUND WATER ISSUE: Ground Water Sample Preservation at ISCO Sites – Recommended Guidelines

    EPA Science Inventory

    In-situ chemical oxidation (ISCO) involves the introduction of a chemical oxidant into the subsurface for the purpose of transforming ground water contaminants into harmless byproducts. Due to oxidant persistence, ground water samples collected at hazardous waste sites may contai...

  7. Ground-water resources of Kansas

    USGS Publications Warehouse

    Moore, R.C.; Lohman, S.W.; Frye, J.C.; Waite, H.A.; McLaughlin, Thad G.; Latta, Bruce

    1940-01-01

    Importance of ground-water resources.—The importance of Kansas' ground-water resources may be emphasized from various viewpoints and in different ways. More than three-fourths of the public water supplies of Kansas are obtained from wells. In 1939, only 60 out of 375 municipal water supplies in Kansas, which is 16 percent, utilized surface waters. If the water wells of the cities and those located on all privately owned land in the state were suddenly destroyed, making it necessary to go to streams, springs, lakes (which are almost all artificial), and ponds for water supply domestic, stock, and industrial use, there would be almost incalculable difficulty and expense. If one could not go to springs, or dig new wells, or use any surface water derived from underground flow, much of Kansas would become uninhabitable.  These suggested conditions seem absurd, but they emphasize our dependence on ground-water resources. Fromm a quantitative standpoint, ground-water supplies existent in Kansas far outweigh surface waters that are present in the state at any one time. No exact figures for such comparison can be given, but, taking 384 square miles as the total surface water area of the state and estimating an average water depth of five feet, the computed volume of surface waters is found to be 1/100th of that of the conservatively estimated ground-water storage in Kansas. The latter takes account only of potable fresh water and is based on an assumed mean thickness of ten feet of reservoir having an effective porosity of twenty percent. It is to be remembered, however, that most of the surface water is run-off, which soon leaves the state, stream valleys being replenished from rainfall and flow from ground-water reservoirs. Most of the ground-water supplies, on the other hand, have existed for many years with almost no appreciable movement--in fact, it is reasonably certain that some well water drawn from beneath the surface of Kansas in 1940 represents rainfall in

  8. Ground-water conditions and studies in Georgia, 2001

    USGS Publications Warehouse

    Leeth, David C.; Clarke, John S.; Craigg, Steven D.; Wipperfurth, Caryl J.

    2003-01-01

    The U.S. Geological Survey (USGS) collects ground-water data and conducts studies to monitor hydrologic conditions, to better define ground-water resources, and address problems related to water supply and water quality. Data collected as part of ground-water studies include geologic, geophysical, hydraulic property, water level, and water quality. A ground-water-level network has been established throughout most of the State of Georgia, and ground-water-quality networks have been established in the cities of Albany, Savannah, and Brunswick and in Camden County, Georgia. Ground-water levels are monitored continuously in a network of wells completed in major aquifers of the State. This network includes 17 wells in the surficial aquifer, 12 wells in the upper and lower Brunswick aquifers, 73 wells in the Upper Floridan aquifer, 10 wells in the Lower Floridan aquifer and underlying units, 12 wells in the Claiborne aquifer, 1 well in the Gordon aquifer, 11 wells in the Clayton aquifer, 11 wells in the Cretaceous aquifer system, 2 wells in Paleozoic-rock aquifers, and 7 wells in crystalline-rock aquifers. In this report, data from these 156 wells were evaluated to determine whether mean-annual ground-water levels were within, below, or above the normal range during 2001, based on summary statistics for the period of record. Information from these summaries indicates that water levels during 2001 were below normal in almost all aquifers monitored, largely reflecting climatic effects from drought and pumping. In addition, water-level hydrographs for selected wells indicate that water levels have declined during the past 5 years (since 1997) in almost all aquifers monitored, with water levels in some wells falling below historical lows. In addition to continuous water-level data, periodic measurements taken in 52 wells in the Camden County-Charlton County area, and 65 wells in the city of Albany-Dougherty County area were used to construct potentiometric-surface maps for

  9. Ground-water recharge in Escambia and Santa Rosa Counties, Florida

    USGS Publications Warehouse

    Grubbs, J.W.

    1995-01-01

    Ground water is a major component of Florida's water resources, accounting for 90 percent of all public-supply and self-supplied domestic water withdrawals, and 58 percent of self-supplied commercial-industrial and agricultural withdrawals of freshwater (Marella, 1992). Ground-water is also an important source of water for streams, lakes, and wetlands in Florida. Because of their importance, a good understanding of these resources is essential for their sound development, use, and protection. One area in which our understanding is lacking is in characterizing the rate at which ground water in aquifers is recharged, and how recharge rates vary geographically. Ground-water recharge (recharge) is the replenishment of ground water by downward infiltration of water from rainfall, streams, and other sources (American Society of Civil Engineers, 1987, p. 222). The recharge rates in many areas of Florida are unknown, of insufficient accuracy, or mapped at scales that are too coarse to be useful. Improved maps of recharge rates will result in improved capabilities for managing Florida's ground-water resources. In 1989, the U.S. Geological Survey, in cooperation with the Florida Department of Environmental Regulation, began a study to delineate high-rate recharge areas in several regions of Florida (Vecchioli and others, 1990). This study resulted in recharge maps that delineated areas of high (greater than 10 inches per year) and low (0 to 10 inches per year) recharge in three counties--Okaloosa, Pasco, and Volusia Counties--at a scale of 1:100,000. This report describes the results of a similar recharge mapping study for Escambia and Santa Rosa Counties (fig. 1), in which areas of high- and low-rates of recharge to the sand-and-gravel aquifer and Upper Floridan aquifer are delineated. The study was conducted in 1992 and 1993 by the U.S. Geological Survey in cooperation with the Florida Department of Environmental Protection.

  10. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of...

  11. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of...

  12. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  13. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Ground-water monitoring systems. 257... Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a) A ground-water monitoring system must be installed that consists of a sufficient number...

  14. 40 CFR 265.91 - Ground-water monitoring system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) to prevent contamination of samples and the ground water. ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A...

  15. Selenium speciation in ground water

    SciTech Connect

    Atalay, A.

    1990-07-10

    Selenium toxicity diseases in animals may occur when the intake exceeds 4 mg/kg and selenium deficiency symptoms may occur when dietary intake is less than 0.04 mg/kg. Since the selenium dietary requirement is very close to toxic concentration, it is important to understand the distribution of selenium in the environment. Selenium occurs in four oxidation states (-II, 0, +IV, and +VI) as selenide, elemental selenium, selenite and selenate. Selenate is reported as more soluble and less adsorbed than selenite. Selenate is more easily leached from soils and is the most available form for plants. Increased mobility of Se into the environment via anthropogenic activities, and the potential oxidation-reduction behavior of the element have made it imperative to study the aquatic chemistry of Se. For this purpose, Se species are divided into two different categories: dissolved Se (in material that passes through filters with 0.45 u openings) and particulate Se (in material of particle size > 0.45 mm) typically suspended sediment and other suspended solids. Element and colloidal phase, not truly dissolved, but passing through the filter is deemed to consist of selenium (-2,0). In dissolved state selenium may exist in three of its four oxidation states; Se(-II), Se(+IV), and Se(+VI). Particulate Se may exist in the same oxidation states as dissolved Se and can be found in different phases of the particulate matter. In sediments, Se may be within the organic material, iron and manganese oxides, carbonates or other mineral phases. The actual chemical forms of Se may be adsorbed to or coprecipitated with these phases (primarily selenite, SeO{sub 3}{sup 2{minus}}) and selenate, SeO{sub 4}{sup 2{minus}}. Selenide, Se(-II), can be covalently bound in the organic portion of a sediment. In addition, Se may be found in anoxic sediments as insoluble metal selenide precipitates, an insoluble elemental Se or as ferroselite (FeSe{sub 2}) and Se containing pyrite.

  16. 77 FR 65150 - Cryovac North America; Withdrawal of Color Additive Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-25

    ... FR 9340), FDA announced that a color additive petition (CAP 4C0276) had been filed by Cryovac North... amended to provide for the safe use of synthetic iron oxide as a color additive in or on cooked meat... Certification to provide for the safe use of synthetic iron oxide as a color additive in or on cooked...

  17. Raft River monitor well potentiometric head responses and water quality as related to the conceptual ground-water flow system

    SciTech Connect

    Allman, D.W.; Tullis, J.A.; Dolenc, M.R.; Thurow, T.L.; Skiba, P.A.

    1982-09-01

    Ground-water monitoring near the Raft River site was initiated in 1974 by the IDWR. This effort consisted of semiannual chemical sampling of 22 irrigation wells near the Raft River geothermal development area. This program yielded useful baseline chemical data; however, several problems were inherent. For example, access to water pumped from the wells is limited to the irrigation season (April through September). All the wells are not continuously pumped; thus, some wells that are sampled one season cannot be sampled the next. In addition, information on well construction, completion, and production is often unreliable or not available. These data are to be supplemented by establishing a series of monitor wells in the proposed geothermal withdrawal and injection area. These wells were to be located and designed to provide data necessary for evaluating and predicting the impact of geothermal development on the Shallow Aquifer system.

  18. Ground water work breakdown structure dictionary

    SciTech Connect

    1995-04-01

    This report contains the activities that are necessary to assess in ground water remediation as specified in the UMTRA Project. These activities include the following: site characterization; remedial action compliance and design documentation; environment, health, and safety program; technology assessment; property access and acquisition activities; site remedial actions; long term surveillance and licensing; and technical and management support.

  19. PRIORITIZATION OF GROUND WATER CONTAMINANTS AND SOURCES

    EPA Science Inventory

    The objective of this research was to identify chemical, physical, bacteriological, and viral contaminants, and their sources, which present the greatest health threat in public ground water supplies in the USA; and to classify (prioritize) such contaminants and relative to their...

  20. Magnificent Ground Water Connection. [Sample Activities].

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC.

    Water conservation and usage is an important concept in science. This document, geared specifically to New England, provides many activities for protecting and discussing ground water situations. Sample activities for grades K-6 include: (1) All the Water in the World; (2) The Case of the Disappearing Water; (3) Deep Subjects--Wells and Ground…

  1. EPA'S GROUND WATER TECHNICAL SUPPORT CENTER

    EPA Science Inventory

    The purpose and the services provided by EPA's Ground Water Technical Support Center (GWTSC) will be presented. In 1987 the Office of Solid Waste and Emergency Response, Regional Waste Management Offices, and ORD established the Technical Support Project (TSP)

    The purpos...

  2. Selenium in Oklahoma ground water and soil

    SciTech Connect

    Atalay, A.; Vir Maggon, D.

    1991-03-30

    Selenium with a consumption of 2 liters per day (5). The objectives of this study are: (1) to determine the concentrations of Se in Oklahoma ground water and soil samples. (2) to map the geographical distribution of Se species in Oklahoma. (3) to relate groundwater depth, pH and geology with concentration of Se.

  3. IN-SITU BIOREMEDIATION OF GROUND WATER

    EPA Science Inventory

    The Robert S. Kerr Environmental Research Laboratory (RSKERL) has developed a number of Issue Papers and Briefing Documents which are designed to exchange up-to-date information related to the remediation of contaminated soil and ground water at hazardous waste sites. n an attemp...

  4. Ground Water Flow No Longer A Mystery

    ERIC Educational Resources Information Center

    Lehr, Jay H.; Pettyjohn, Wayne A.

    1976-01-01

    Examined are the physical characteristics of ground water movement. Some potential pollution problems are identified. Models are used to explain mathematical and hydraulic principles of flow toward a pumping well and an effluent stream, flow around and through lenticular beds, and effects of pumping on the water table. (Author/MR)

  5. NITRATE CONTAMINATION OF GROUND WATER (GW-761)

    EPA Science Inventory

    The occurrence of nitrate and related compounds in ground water is discussed from the perspectives of its natural as well as anthropogenic origins. A brief explanation of the nitrogen cycle touches on the production as well as utilization of ammonia, nitrite, nitrate, and nitrog...

  6. Occurrence of microbial indicators in various ground water sources

    SciTech Connect

    Shadix, L.C.; Newport, B.S.; Crout, S.R.; Lieberman, R.J.

    1996-11-01

    The United States Environmental Protection Agency (USEPA) and the American Water Works Association Research Foundation (AWWARF) have been collaborating in an ongoing study to research the application of molecular biology techniques versus conventional techniques for monitoring and consequently to obtain ground water microbial occurrence data. The bacterial assays described below were performed during the course of the USEPA/AWWARF study in addition to enteric virus, bacteriophage and Legionella assays to provide occurrence information and also to investigate the potential use of fecal indicator organisms as surrogates for enteric viruses. This paper presents occurrence data obtained for total coliform, Escherichia coli (E. coli), fecal enterococci and Clostridium perfringens (C. perfringens) bacteria from samples collected at thirty public ground water supplies.

  7. Geology and ground water of the Tualatin Valley, Oregon

    USGS Publications Warehouse

    Hart, D.H.; Newcomb, R.C.

    1965-01-01

    The Tualatin Valley proper consists of broad valley plains, ranging in altitude from 100 to 300 feet, and the lower mountain slopes of the drainage basin of the Tualatin River, a tributary of the Willamette River in northwestern Oregon. The valley is almost entirely farmed. Its population is increasing rapidly, partly because of the expansion of metropolitan Portland. Structurally, the bedrock of the basin is a saucer-shaped syncline almost bisected lengthwise by a ridge. The bedrock basin has been partly filled by alluvium, which underlies the valley plains. Ground water occurs in the Columbia River basalt, a lava unit that forms the top several hundred feet of the bedrock, and also in the zones of fine sand in the upper part of the alluvial fill. It occurs under unconfined, confined, and perched conditions. Graphs of the observed water levels in wells show that the ground water is replenished each year by precipitation. The graphs show also that the amount and time of recharge vary in different aquifers and for different modes of ground-water occurrence. The shallower alluvial aquifers are refilled each year to a level where further infiltration recharge is retarded and water drains away as surface runoff. No occurrences of undue depletion of the ground water by pumping are known. The facts indicate that there is a great quantity of additional water available for future development. The ground water is developed for use by some spring works and by thousands of wells, most of which are of small yield. Improvements are now being made in the design of the wells in basalt and in the use of sand or gravel envelopes for wells penetrating the fine-sand aquifers. The ground water in the basalt and the valley fill is in general of good quality, only slightly or moderately hard and of low salinity. Saline and mineralized water is present in the rocks of Tertiary age below the Columbia River basalt. Under certain structural and stratigraphic conditions this water of poor

  8. Hydrogeology and Simulated Ground-Water Flow in the Salt Pond Region of Southern Rhode Island

    USGS Publications Warehouse

    Masterson, John P.; Sorenson, Jason R.; Stone, Janet R.; Moran, S. Bradley; Hougham, Andrea

    2007-01-01

    distribution of direct ground-water discharge and ground-water-derived surface-water (streamflow) discharge to the salt ponds, but still provided a reasonable match to the hydrologic data available for model calibration. To reduce the uncertainty in predictions of watershed areas and ground-water discharge to the salt ponds, additional hydrogeologic data would be required to constrain the model input parameters that have the greatest effect on the simulation results.

  9. Selected ground-water data for Yucca Mountain region, southern Nevada and eastern California, through December 1994

    USGS Publications Warehouse

    Westenburg, C.L.; La Camera, R. J.

    1996-01-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 36 sites, ground-water discharge at 6 sites, and ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1994. Data collected prior to 1994 are graphically presented and data collected by other agencies (or as part of other programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992-94.

  10. Ground-water conditions in Georgia, 1993

    USGS Publications Warehouse

    Joiner, C.N.; Cressler, A.M.

    1994-01-01

    Ground-water conditions during 1993 and recent ground-water level and quality trends in Georgia were evaluated using data from precipitation, ground-water, and ground-water quality monitoring networks. Data for 1993 included in this report are from precipitation records from 10 National Weather Service stations, continuous water-level records from 72 wells, and chloride analyses from 13 wells. Annual mean ground-water levels in Georgia in 1993 ranged from about 3.2 feet higher to about 9.6 feet lower than in 1992. Of the 72 wells summarized in this report, 30 wells had annual mean water levels that were higher and 42 wells had annual mean water levels that were lower in 1993 than in 1992. Record-high daily mean water levels were recorded in one well tapping the surficial aquifer, one well tapping the Upper Floridan aquifer, one well tapping the Claiborne aquifer, and one well tapping the crystalline- rock aquifers. These record highs were from about 0.1 to 0.7 feet higher than previous record highs. Record-low daily mean water levels were recorded in one well tapping the surficial aquifer, two wells tapping the Upper Floridan aquifer, four wells tapping the Cretaceous aquifer, one well tapping the Dublin-Midville aquifer system, and one well tapping the crystalline-rock aquifers. These record lows were from about 0.1 foot to 7.2 feet lower than the previous record lows. Chloride concentration in water from the Upper Floridan aquifer in most of coastal Georgia was below drinking water standards established by the Georgia Department of Natural Resources and the U.S. Environmental Protection Agency and has not changed appreciably with time. However, chloride concentration in water from some wells that tap the Floridan aquifer system in the Brunswick area exceeds the drinking water standards.

  11. Geology and ground-water resources of the Ahtanum Valley, Yakima County, Washington

    USGS Publications Warehouse

    Foxworthy, B.L.

    1962-01-01

    , variations in the flow of irrigation ditches and in rates of water application, variations in local precipitation, and seasonal differences in withdrawals from wells. Annual fluctuations of levels generally are less than 10 feet except in localities of heavy pumping. Periodic measurements of water levels in two observation wells in the area indicate, locally at least, a persistent decline in artesian pressures in confined basalt aquifers, although the record is too short to show whether withdrawal by pumping has reached, or is nearing, an optimum balance with recharge. The aquifers are recharged by precipitation, by infiltration from streams, and by ground-water underflow into the area. Ground water is discharged by seepage to streams, by evapotranspiration, by springs and seeps at the land surface, and, artificially, by withdrawal from wells. It is estimated that the seepage discharge to the Yakima River from the area studied may range from about 20,000 to 25,000 acre-feet per year. The consumptive waste of ground water by phreatophytes probably exceeds 4,000 acre-feet per year and may represent a large reclaimable source of water in the area. The annual withdrawal of ground water from wells in the area for domestic, industrial, irrigation, public, and stock supplies is estimated to be 6,300 acre-feet. The chemical quality of the ground water generally is satisfactory for most purposes, although the water from many wells is harder than is desirable for domestic use.

  12. An initial inverse calibration of the ground-water flow model for the Hanford unconfined aquifer

    SciTech Connect

    Jacobson, E.A. . Desert Research Inst.); Freshly, M.D. )

    1990-03-01

    Large volumes of process cooling water are discharged to the ground form U.S. Department of Energy (DOE) nuclear fuel processing operations in the central portion of the Hanford Site in southeastern Washington. Over the years, these large volumes of waste water have recharged the unconfined aquifer at the Site. This artificial recharge has affected ground-water levels and contaminant movement in the unconfined aquifer. Ground-water flow and contaminant transport models have been applied to assess the impacts of site operations on the rate and direction of ground-water flow and contaminant transport in unconfined aquifer at the Hanford Site. The inverse calibration method developed by Neuman and modified by Jacobson was applied to improve calibration of a ground-water flow model of the unconfined aquifer at the Hanford Site. All information about estimates of hydraulic properties of the aquifer, hydraulic heads, boundary conditions, and discharges to and withdrawals form the aquifer is included in the inverse method to obtain an initial calibration of the ground-water flow model. The purpose of this report is to provide a description of the inverse method, its initial application to the unconfined aquifer at Hanford, and to present results of the initial inverse calibration. 28 refs., 19 figs., 1 tab.

  13. Ground-water sample collection and analysis plan for the ground-water surveillance project

    SciTech Connect

    Bryce, R.W.; Evans, J.C.; Olsen, K.B.

    1991-12-01

    The Pacific Northwest Laboratory performs ground-water sampling activities at the US Department of Energy`s (DOE`s) Hanford Site in support of DOE`s environmental surveillance responsibilities. The purpose of this document is to translate DOE`s General Environmental Protection Program (DOE Order 5400.1) into a comprehensive ground-water sample collection and analysis plan for the Hanford Site. This sample collection and analysis plan sets forth the environmental surveillance objectives applicable to ground water, identifies the strategy for selecting sample collection locations, and lists the analyses to be performed to meet those objectives.

  14. Ground-water sample collection and analysis plan for the ground-water surveillance project

    SciTech Connect

    Bryce, R.W.; Evans, J.C.; Olsen, K.B.

    1991-12-01

    The Pacific Northwest Laboratory performs ground-water sampling activities at the US Department of Energy's (DOE's) Hanford Site in support of DOE's environmental surveillance responsibilities. The purpose of this document is to translate DOE's General Environmental Protection Program (DOE Order 5400.1) into a comprehensive ground-water sample collection and analysis plan for the Hanford Site. This sample collection and analysis plan sets forth the environmental surveillance objectives applicable to ground water, identifies the strategy for selecting sample collection locations, and lists the analyses to be performed to meet those objectives.

  15. Atlas of ground-water resources in Puerto Rico and the U.S. Virgin Islands

    USGS Publications Warehouse

    Veve, Thalia D.; Taggart, Bruce E.

    1996-01-01

    This atlas presents an overview of the ground-water resources of the main island of Puerto Rico; two of its larger offshore islands, Isla de Culebra and Isla de Vieques; and the three principal islands of the U.S. Virgin Islands, St. Thomas, St. John, and St. Croix. The atlas presents the most important ground-water information available for these islands, and is written for water managers and the general public. It describes, through the use of maps, graphs, and hydrogeologic sections, the most important aspects of the geohydrology, ground-water flow system, and groundwater withdrawals for the principal aquifers in these islands. Most of the information presented in the atlas is from published reports, although unpublished data from ongoing studies by the U.S. Geological Survey were used to prepare parts of the atlas. This report provides a useful compilation of information concerning major aquifers in Puerto Rico and the U.S. Virgin Islands and provides a first step in gaining a general knowledge of these aquifers. More detailed information is available from the primary sources referenced in the report. The atlas contains an introductory section and 15 sections describing the ground-water resources of 12 regions within the 7 ground-water areas of the main island of Puerto Rico, Isla de Culebra and Isla de Vieques (described in a single section of the atlas), and the U.S. Virgin Islands (St. Thomas and St. John are described in one section of the atlas and St. Croix in another), and a concluding section describing present and potential problems related to the development of ground-water resources. Information presented in each of 15 descriptive sections of the atlas include the (1) location and major geographic features of the area covered by that section, (2) population and estimated (4) hydrogeology of the area, (5) ground-water levels and movements, and (6) a description of soil permeabilities.

  16. 78 FR 43093 - Sensient Technologies Corporation; Withdrawal of Color Additive Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... Register of August 24, 1998 (63 FR 45073), FDA announced that a color additive petition (CAP 8C0261) had... the color additive regulations be amended to provide for the safe use of External D&C Violet No. 2 in... Certification to provide for the safe use of External D&C Violet No. 2 in coloring externally applied...

  17. Areas contributing ground water to the Peconic Estuary, and ground-water budgets for the north and south forks and Shelter Island, eastern Suffolk County, New York

    USGS Publications Warehouse

    Schubert, C.E.

    1998-01-01

    The Peconic Estuary, at the eastern end of Long Island, has been plagued by a recurrent algal bloom, locally referred to as ?Brown Tide,? that has caused the severe decline of local marine resources. Although the factors that trigger Brown Tide blooms remain uncertain, groundwater discharge has previously been shown to affect surface-water quality in the western part of the estuary. A U.S. Geological Survey groundwater- flow model of the main body of Long Island indicates that a total of about 7.5 x 106 ft3/d (cubic feet per day) of freshwater discharges to the western part of the estuary, but the model does not include the ground-water flow systems on the North and South Forks and Shelter Island, which contribute significant amounts of freshwater to the central and eastern parts of the estuary. The need for information on freshwater discharge to the entire estuary prompted the U.S. Geological Survey to evaluate ground-water discharge from the North and South Forks and Shelter Island. Source areas that contribute ground water to the Peconic Estuary were delineated, and groundwater budgets for these areas were developed, to evaluate the distribution and magnitude of ground-water discharge to the central and eastern parts of the estuary. Contributing-area boundaries that were delineated coincide with the hydraulic boundaries of the fresh ground-water-flow systems of the North and South Forks and Shelter Island; these boundaries are of two types? external (saltwater bodies) and internal (groundwater divides). Hydrologic components that were evaluated include recharge from precipitation, public-supply withdrawal and return flow, and agricultural withdrawal. Values for each of these components were calculated or estimated for the individual freshwater flow subsystems that form each ground-water-budget area, then summed to obtain the total discharge of fresh ground water to tidewater. Ground-water discharge to the Peconic Estuary is about 3.8 x 106 ft3/d from the North

  18. Evaluation of Ground Water Near Sidney, Western Nebraska, 2004-05

    USGS Publications Warehouse

    Steele, G.V.; Sibray, S.S.; Quandt, K.A.

    2007-01-01

    During times of drought, ground water in the Lodgepole Creek area around Sidney, western Nebraska, may be insufficient to yield adequate supplies to private and municipal wells. Alternate sources of water exist in the Cheyenne Tablelands north of the city, but these sources are limited in extent. In 2003, the U.S. Geological Survey and the South Platte Natural Resources District began a cooperative study to evaluate the ground water near Sidney. The 122-square-mile study area lies in the south-central part of Cheyenne County, with Lodgepole Creek and Sidney Draw occupying the southern and western parts of the study area and the Cheyenne Tablelands occupying most of the northern part of the study area. Twenty-nine monitoring wells were installed and then sampled in 2004 and 2005 for physical characteristics, nutrients, major ions, and stable isotopes. Some of the 29 sites also were sampled for ground-water age dating. Ground water is limited in extent in the tableland areas. Spring 2005 depths to ground water in the tableland areas ranged from 95 to 188 feet. Ground-water flow in the tableland areas primarily is northeasterly. South of a ground-water divide, ground-water flows southeasterly toward Lodgepole Creek Valley. Water samples from monitoring wells in the Ogallala Group were predominantly a calcium bicarbonate type, and those from monitoring wells in the Brule Formation were a sodium bicarbonate type. Water samples from monitoring wells open to the Brule sand were primarily a calcium bicarbonate type at shallow depths and a sodium bicarbonate type at deeper depths. Ground water in Lodgepole Creek Valley had a strong sodium signature, which likely results from most of the wells being open to the Brule. Concentrations of sodium and nitrate in ground-water samples from the Ogallala were significantly different than in water samples from the Brule and Brule sand. In addition, significant differences were seen in concentrations of calcium between water samples

  19. Development and use of a mathematical model of the San Bernardino Valley ground-water basin, California

    USGS Publications Warehouse

    Hardt, William F.; Hutchinson, C.B.

    1980-01-01

    Part of the San Bernardino urbanized area in California overlies formerly swampy lands with a history of flowing wells. This area , upgradient from and adjacent to the San Jacinto fault, contains a zone in an alluvial ground-water basin that is under artesian pressure. Since 1945, withdrawals have exceeded recharge and caused head declines of more than 100 feet. Artificial recharge of imported water in the upgradient areas may cause ground-water levels to rise, which could cause abandoned but unplugged wells to resume flowing. If so, structures could be damaged. A two-layer Galerkin finite-element digital model was used for predicting the rate and extent of the rise in water levels from 1975 to 2000. Six hydrologic conditions were modeled for the basin. Artificial recharge of one-half entitlement and full entitlement from the California Aqueduct were each coupled with low, average, and high natural recharge to the basin. According to model predictions, the greatest water level rises will be along the San Bernardino front. This area encompasses the artificial recharge sites and also has a thick section of unsaturated sediments for storing ground water. The formerly swampy lands between Warm Creek and the Santa Ana River adjacent to the San Jacinto fault have little additional storage capacity, and water levels could rise to the land surface as early as 1983 under maximum recharge conditions and 1970-74 average pumping conditions. If pumping rates are reduced in the Warm Creek area, water levels may rise to land surface prior to the dates predicted by the model, regardless of the artificial-recharge program. (USGS)

  20. Ground-water-level monitoring network, Hollister and San Juan Valleys, San Benito County, California

    USGS Publications Warehouse

    Farrar, C.D.

    1981-01-01

    The addition of 17 wells to the existing 86-well network is proposed to improve the ground-water monitoring in the Hollister and San Juan Valleys in California. The new wells were selected on the basis of well-construction data, availability, location, accessibility, use, and condition, either to replace wells that are no longer accessible or to furnish needed additional data for planning artificial recharge, preparing water-level-contour maps, and digital ground-water modeling. (USGS)

  1. Maps showing ground-water conditions in the lower Santa Cruz area, Pinal, Pima, and Maricopa Counties, Arizona, 1977

    USGS Publications Warehouse

    Konieczki, A.D.; English, C.S.

    1979-01-01

    The lower Santa Cruz area includes about 5,400 square miles in south-central Arizona and is the second largest agricultural area in the State. The area depends mainly on ground water for irrigation, and in 1976 about 966,000 acre-feet of ground water was pumped from the area. As a result of the large-scale long-term withdrawal of ground water, water levels have declined , and the direction of ground-water flow has changed. Since 1923 , declines of nearly 500 feet have occurred near Stanfield. Information shown on the maps (scale 1:125,000) includes depth to water, altitude of the water level, specific conductance, fluoride concentration, change in water level (1923-77), and land use. Hydrographs of the water level in selected wells and a table of historical pumpage also are included. (Woodard-USGS)

  2. Chemistry and movement of ground water, Nevada Test Site

    USGS Publications Warehouse

    Schoff, S.L.; Moore, J.E.

    1964-01-01

    Three chemical types of ground water are distinguished at the Nevada Test Site and vicinity. A sodium-potassium water is related to tuff (in part zeolitized) and to alluvium containing detrital tuff. A calcium-magnesium water is related to limestone and dolomite, or to alluvium containing detritus of these rock types. A mixed chemical type, containing about as much sodium and potassium as calcium and magnesium, may result from the addition of one of the first two types of water to the other; to passage of water first through tuff and then through carbonate rock, or vice versa; and to ion-exchange during water travel. Consideration of the distribution of these water types, together with the distribution of sodium in the water and progressive changes in the dissolved solids, suggests that the ground water in the Nevada Test Site probably moves toward the Amargosa Desert, not into Indian Spring Valley and thence southeastward toward Las Vegas. The low dissolved solids content of ground-water reservoirs in alluvium and tuff of the enclosed basins indicates that recharge is local in origin.

  3. User interface for ground-water modeling: Arcview extension

    USGS Publications Warehouse

    Tsou, M.-S.; Whittemore, D.O.

    2001-01-01

    Numerical simulation for ground-water modeling often involves handling large input and output data sets. A geographic information system (GIS) provides an integrated platform to manage, analyze, and display disparate data and can greatly facilitate modeling efforts in data compilation, model calibration, and display of model parameters and results. Furthermore, GIS can be used to generate information for decision making through spatial overlay and processing of model results. Arc View is the most widely used Windows-based GIS software that provides a robust user-friendly interface to facilitate data handling and display. An extension is an add-on program to Arc View that provides additional specialized functions. An Arc View interface for the ground-water flow and transport models MODFLOW and MT3D was built as an extension for facilitating modeling. The extension includes preprocessing of spatially distributed (point, line, and polygon) data for model input and postprocessing of model output. An object database is used for linking user dialogs and model input files. The Arc View interface utilizes the capabilities of the 3D Analyst extension. Models can be automatically calibrated through the Arc View interface by external linking to such programs as PEST. The efficient pre- and postprocessing capabilities and calibration link were demonstrated for ground-water modeling in southwest Kansas.

  4. In Situ Tritium Probe for Ground Water Monitoring

    NASA Astrophysics Data System (ADS)

    Hull, C.

    2001-12-01

    The U.S. Department of Energy (USDOE)/National Nuclear Security Administration (NNSA) has requested a probe system that can provide daily measurements of tritium in ground waters, fit into 5 cm diameter ground water monitor wells, and survive extended periods (months to years) at hydrostatic pressures of 12,000 kPa (1800 psi) and water temperatures to 60oC. The analytical Minimum Detectable Limit Allowable (MDA) requested for tritium in solution is <1,000 picoCuries per liter (pCi L-1) and preferably <300 pCi L-1 (11 Bq L-1). The In Situ Tritium probe system (ITP) must produce analytical results without drawing a ground water sample to the surface while operating unattended and automatically download data from remote well sites without external power or communication lines. An ITP has been developed that satisfies most of these requirements. A prototype system that demonstrated proof-of-principal was deployed successfully in shallow monitor wells. Ground water samples were processed and analyzed onboard the prototype ITP and data automatically transmitted to the wellhead. A third generation tritium detection and measurement cell that quantitatively measures dissolved tritium at activities <2,000 pCi L-1 has been tested under laboratory conditions. This, or a more sensitive, detection cell will be integrated into the ITP platform and deployed for extensive tests in deep monitor wells at the USDOE/NNSA Nevada Test Site within the next two years. Ultimate goals for the ITP system are low detection limits for dissolved tritium (<300 pCi L-1) plus additional analytical capabilities for nuclear and chemical parameters such as in situ gamma and neutron fluxes, pH, EH, EC, concentrations of specific aqueous components, etc.

  5. SELECTED GROUND-WATER DATA FRO YUCCA MOUNTAIN REGION, SOUTHERN NEVADA AND EASTERN CALIFORNIA, THROUGH DECEMBER 1998

    SciTech Connect

    C.G. Groat

    2000-11-29

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 34 wells and a fissure (Devils Hole), ground-water discharge at 5 springs and a flowing well, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1998. Data collected prior to 1998 are graphically presented and data collected by other agencies (or as part of other Geological Survey programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992-98. At two water-supply wells and a nearby observation well, median water levels for calendar year 1998 were slightly lower (0.2 to 0.3 foot) than for their respective baseline periods. At the remaining four wells in Jackass Flats, median water levels for 1998 were unchanged at two wells and slightly higher (0.4 and 1.4 foot) at two wells than those for their respective baseline periods.

  6. Selected ground-water data for Yucca Mountain region, southern Nevada and eastern California, through December 1996

    SciTech Connect

    LaCamera, R.J.; Locke, G.L.

    1997-12-31

    The US Geological Survey, in support of the US Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 36 sites, ground-water discharge at 6 sites, and ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1996. Data collected prior to 1996 are graphically presented and data collected by other agencies (or as part of other programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented to indicate potential effects of ground-water withdrawals in support of US Department of Energy activities near Yucca Mountain. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992--96. At two water-supply wells and a nearby observation well, median water levels for calendar year 1996 were slightly lower (0.3 to 0.4 foot) than for the respective baseline periods. At four other wells in Jackass Flats, median water levels for 1996 were unchanged, slightly lower (0.2 foot), and slightly higher (0.2 and 0.7 foot) than for the respective baseline periods.

  7. Selected ground-water data for Yucca Mountain region, southern Nevada and eastern California, through December 1998

    USGS Publications Warehouse

    Locke, Glenn L.

    2001-01-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 34 wells and a fissure (Devils Hole), ground-water discharge at 5 springs and a flowing well, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1998. Data collected prior to 1998 are graphically presented and data collected by other agencies (or as part of other Geolgical Survey programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992-98. At two water-supply wells and a nearby observation well, median water levels for calendar year 1998 were slightly lower (0.2 to 0.3 foot) than for their respective baseline periods. At the remaining four wells in Jackass Flats, median water levels for 1998 were unchanged at two wells and slightly higher (0.4 and 1.4 foot) at two wells than those for their respective baseline periods.

  8. Selected ground-water data for Yucca Mountain region, southern Nevada and eastern California, through December 1999

    USGS Publications Warehouse

    Locke, G.L.

    2001-01-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 34 wells and a fissure (Devils Hole), ground-water discharge at 5 springs and a flowing well, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1999. Data collected prior to 1999 are graphically presented and data collected by other agencies (or as part of other Geological Survey programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992-99. At two water-supply wells median water levels for calendar year 1999 were unchanged from their respective baseline periods. At a nearby observation well, the 1999 median water level was slightly lower (0.1 foot) than its baseline period. At the remaining four wells in Jackass Flats, median water levels for 1999 were slightly higher (0.2 foot to 1.6 feet) than for their respective baseline periods.

  9. Hydrogeology of, and Simulation of Ground-Water Flow In, the Pohatcong Valley, Warren County, New Jersey

    USGS Publications Warehouse

    Carleton, Glen B.; Gordon, Alison D.

    2007-01-01

    ), chlorofluorocarbon (CFC), and tritium-helium age-dating techniques range from 0 to 27 years, with a median age of 6 years. Land-surface and ground-water water budgets were calculated, yielding an estimated rate of direct recharge tothe surficial aquifer of about 23 in/yr, and an estimated net recharge to the ground-water system within the area underlain by carbonate rock (11.4 mi2) of 29 in/yr (10 in/yr over the entire 33.3 mi2 basin). A finite-difference, numerical model was developed to simulate ground-water flow in the Pohatcong Valley. The four-layer model encompasses the entire carbonate-rock part of the valley. The carbonate-rock aquifer was modeled as horizontally anisotropic, with the direction of maximum transmissivity aligned with the longitudinal axis of the valley. All lateral boundaries are no-flow boundaries. Recharge was applied uniformly to the topmost active layer with additional recharge added near the lateral boundaries to represent infiltration of runoff from adjacent crystalline-rock areas. The model was calibrated to June 2001 water levels in wells completed in the carbonate-rock aquifer, August 2000 stream base-flow measurements, and the approximate ground-water age. The ground-water-flow model was constructed in part to test possible site contamination remediation alternatives. Four previously determined ground-water remediation alternatives (GW1, GW2, GW3, and GW4) were simulated. For GW1, the no-action alternative, simulated pathlines originating in the tetrachloroethene (PCE) and trichloroethene (TCE) source areas within the Ground-Water Contamination Site end at Pohatcong Creek near the confluence with Shabbecong Creek, although some particles went deeper in the aquifer system and ultimately discharge to Pohatcong Creek about 10 miles downvalley in Pohatcong Township. Remediation alternatives GW2, GW3, and GW4 include ground-water withdrawal, treatment, and reinjection. The design for GW2 includes wells in the TCE and PCE source areas that wit

  10. 75 FR 17939 - EMD Chemicals, Inc.; Withdrawal of Color Additive Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-08

    ... the Federal Register of September 25, 1998 (63 FR 51359), FDA announced that a color additive petition... published an amended filing notice in the Federal Register of June 21, 1999 (64 FR 33097), indicating that... candies, nutritional supplement tablets and gelatin capsules, and chewing gum (71 FR 31927). The...

  11. 75 FR 10808 - CIBA Vision Corp.; Withdrawal of Color Additive Petitions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-09

    .... SUPPLEMENTARY INFORMATION: In a notice published in the Federal Register of August 17, 2005 (70 FR 48426), FDA....) Pigment Violet 19, C.I. Pigment Yellow 154, and C.I. Pigment Red 122 as color additives in contact lenses.... Pigment Violet 19 (CAP 5C0278, Docket No. FDA-2005-C- 0245), C.I. Pigment Yellow 154 (CAP 5C0279,...

  12. Ground water maps of the Hanford Site

    SciTech Connect

    Kasza, G.L.; Harris, S.F.; Hartman, M.J.

    1990-12-01

    This report presents the results of the June 1990, ground water level measurement program at the 100 Areas and 200 Areas of the Hanford Site (Figure 1). The water levels beneath these areas are measured regularly on a semiannual basis and the data received are used to produce the following set of maps for public release. For clarity, the locating prefixes have been omitted from all well numbers shown on the maps. Wells in the 100 Areas have the prefix 199; wells in the 200 Areas have the prefix 299, and the wells outside these areas have the prefix 699. Ground Water Maps of the Hanford Site is prepared by the Geosciences Group, Environmental Division, Westinghouse Hanford Company, for the US Department of Energy, Richland Operations Office. 1 ref., 6 figs., 2 tabs.

  13. Ground-water data for Georgia, 1980

    USGS Publications Warehouse

    Matthews, S.E.; Hester, Willis G.; O'Byrne, M. P.

    1981-01-01

    More than 2,000 water-level measurements made in Georgia in 1980 provided the basic data for this report. Daily mean water-level fluctuations and trends are shown in hydrographs for the previous year and fluctuations of the monthly mean water level are shown for the previous 10 years in selected observation wells in Georgia. Monitoring ground-water levels is essential to the understanding of storage changes in a ground-water reservoir or aquifer. Fluctuations and long-term trends in water levels occur as a result of recharge to and discharge from the reservoir. Mean annual water levels across Georgia were from 1.92 feet higher to 12.61 feet lower in 1980 than in 1979, and in some areas were the lowest on record. (USGS)

  14. Procedures for ground-water investigations

    SciTech Connect

    Not Available

    1989-09-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water investigations are carried out to fulfill the requirements for the US Department of Energy (DOE) to meet the requirements of DOE Orders. Investigations are also performed for various clients to meet the requirements of the Resource Conservation and Recovery Act of 1976 (RCRA) and the Comprehensive Environmental Response, Compensation and Liability Act of 1980 (CERCLA). National standards including procedures published by the American Society for Testing and Materials (ASTM) and the US Geological Survey were utilized in developing the procedures contained in this manual.

  15. Evaluation of the ground-water resources of the lower Susquehanna River basin, Pennsylvania and Maryland

    USGS Publications Warehouse

    Gerhart, James M.; Lazorchick, George J.

    1988-01-01

    than the corresponding averages for the other lithologies. The Cumberland Valley carbonate rocks have the greatest gaining-stream leakage coefficient--about 43 feet per day. The specific yields are 0.035, 0.020, 0.020, and 0.007 for the carbonate, Paleozoic sedimentary, crystalline, and Triassic sedimentary units, respectively. The calibrated model was used to simulate the effects of a ground-water withdrawal of 1 inch per year on water-table altitudes and average annual base flows in the modeled area. The overall effect is least for the carbonate units and greatest for the Triassic sedimentary units. The model also was used to simulate a standardized potential yield for each unit by assuming that the maximum acceptable consequence of a hypothetical withdrawal scheme is an ultimate 50-percent reduction in average annual base flow. Based on this, the potential yield for the modeled area is 891 million gallons per day. The Cumberland Valley carbonate rocks have the greatest potential yield--0.47 million gallons per day per square mile. The carbonate units have the greatest average potential yield, followed by the Paleozoic sedimentary, crystalline, and Triassic sedimentary units. About 90 percent of the eventual decline in water-table altitudes and the eventual reduction in average annual base flows occurs within 5 years of the implementation of the hypothetical withdrawal scheme. Nearly all of the ground water withdrawn is derived from reduced discharge to streams. The calibrated model can be used to estimate the impacts of ground-water development schemes on regional ground-water levels and base flows of streams, it cannot be used to simulate local cones of depression or local base-flow changes. The reliability of the model is a function of its approximation of the physical characteristics of the ground-water flow system, the two calibrations, various simplifying assumptions, and the lack of calibration under ground-water withdrawal conditions, it ca

  16. Evaluation of the ground-water resources of parts of Lancaster and Berks Counties, Pennsylvania

    USGS Publications Warehouse

    Gerhart, J.M.; Lazorchick, G.J.

    1984-01-01

    Secondary openings in bedrock are the avenues for virtually all ground-water flow in a 626-sqare-mile area in Lancaster and Berks Counties, Pennsylvania. The number, size, and interconnection of secondary openings are functions of lithology, depth, and topography. Ground water actively circulates to depths of 150 to 300 feet below land surface. Total average annual ground-water recharge for the area is 388 million gallons per day, most of which discharges to streams from local, unconfined flow systems. A digital ground-water flow model was developed to simulate unconfined flow under several different recharge and withdrawal scenarios. On the basis of lithologic and hydrologic differences, the modeled area was sub-divided into 22 hydrogeologic units. A finite-difference grid with rectangular blocks, each 2,015 by 2,332 feet, was used. The model was calibrated under steady-state and transient conditions. The steady-state calibration was used to determine hydraulic conductivities and stream leakage coefficients and the transient calibration was used to determine specific yields. The 22 hydrogeologic units fall into four general lithologies: Carbonate rocks, metamorphic rocks, Paleozoic sedimentary rocks, and Triassic sedimentary rocks. Average hydraulic conductivity ranges from about 8.8 feet per day in carbonate units to about .5 feet per day in metamorphic units. The Stonehenge Formation (limestone) has the greatest average hydraulic conductivity--85.2 feet per day in carbonate units to about 0.11 feet per day in the greatest gaining-strem leakage coefficient--16.81 feet per day. Specific yield ranges from 0.06 to 0.09 in carbonate units, and is 0.02 to 0.015, and 0.012 in metamorphic, Paleozoic sedimentary, and Triassic sedimentary units, respectively. Transient simulations were made to determine the effects of four different combinations of natural and artificial stresses. Natural aquifer conditions (no ground-water withdrawals) and actual aquifer conditions

  17. Ground Water Atlas of the United States: Segment 7, Idaho, Oregon, Washington

    USGS Publications Warehouse

    Whitehead, R.L.

    1994-01-01

    , generally in areas of privately owned land (fig. 1). In many places, deeper wells produce water from underlying volcanic rocks, usually basalt. Most irrigation (fig. 2) is on lowlands next to streams and on adjacent terraces. Generally, lowlands within a few miles of a main stream are irrigated with surface water diverted by gravity flow from the main stream or a reservoir and distributed through a system of canals and ditches. In some areas, water is pumped to irrigate lands farther from the stream at a higher altitude. Along the Snake and Columbia Rivers, large pumping systems withdraw billions of gallons of water per day from the rivers to irrigate adjacent uplands that are more than 500 feet higher than the rivers. Elsewhere, irrigation water is obtained from large-capacity wells, where depth to water might exceed 500 feet below land surface. Aquifers in Idaho, Oregon, and Washington, as in most other States, differ considerably in thickness and permeability, and well yields differ accordingly. Ground-water levels in a few areas have declined as a result of withdrawals by wells. State governments have taken steps to alleviate declines in some areas by enacting programs that either limit the number of additional wells that can be completed in a particular aquifer (Ground-Water Management Area) or prevent further ground-water development (Critical Ground-Water Area). Segment 7 includes some of the driest parts of the Nation, as well as some of the wettest. Average annual precipitation (1951-80) ranges from less than 10 inches in arid parts of Idaho, Oregon, and Washington to more than 80 inches in the western parts of Oregon and Washington (fig. 3). Most storms generally move eastward through the area. The eastward-moving air absorbs the moisture that evaporates from the Pacific Ocean. As this air encounters the fronts of mountain ranges, it rises, cools, and condenses. Accordingly, the western sides of the mountain ranges receive the most precipitation.

  18. Ground water and the rural homeowner

    USGS Publications Warehouse

    Waller, Roger M.

    1994-01-01

    As the salesmen sang in the musical The Music Man, "You gotta know the territory." This saying is also true when planning to buy or build a house. Learn as much as possible about the land, the water supply, and the septic system of the house before buying or building. Do not just look at the construction aspects or the beauty of the home and surroundings. Be sure to consider the environmental conditions around and beneath the site as well. Try to visit the site under adverse conditions, such as during heavy rain or meltwater runoff, to observe the drainage characteristics, particularly the condition of the basement. Many of the conditions discussed in this book, such as lowered well-water levels, flooded basements, and contamination from septic systems, are so common that rural families often have to deal with one or more of them. The purpose of this book is to awaken an interest in ground water and an awareness of where it is available, how it moves, how people can adjust to its patterns to avoid problems, and how it can be protected and used wisely. This booklet provides both present and prospective rural homeowners, particularly those in the glaciated northern parts of the United States, with a basic but comprehensive description of ground water. It also presents problems one may expect to encounter with ground water and some solutions or suggestions for help with these problems.

  19. Ground water and the rural homeowner

    USGS Publications Warehouse

    Waller, Roger M.

    1988-01-01

    As the salesmen sang in the musical The Music Man, "You gotta know the territory." This saying is also true when planning to buy or build a house. Learn as much as possible about the land, the water supply, and the septic system of the house before buying or building. Do not just look at the construction aspects or the beauty of the home and surroundings. Be sure to consider the environmental conditions around and beneath the site as well. Try to visit the site under adverse conditions, such as during heavy rain or meltwater runoff, to observe the drainage characteristics, particularly the condition of the basement. Many of the conditions discussed in this book, such as lowered well-water levels, flooded basements, and contamination from septic systems, are so common that rural families often have to deal with one or more of them. The purpose of this book is to awaken an interest in ground water and an awareness of where it is available, how it moves, how people can adjust to its patterns to avoid problems, and how it can be protected and used wisely. This booklet provides both present and prospective rural homeowners, particularly those in the glaciated northern parts of the United States, with a basic but comprehensive description of ground water. It also presents problems one may expect to encounter with ground water and some solutions or suggestions for help with these problems.

  20. Simulation of ground-water flow and areas contributing ground water to production wells, Cadillac, Michigan

    USGS Publications Warehouse

    Hoard, Christopher J.; Westjohn, David B.

    2005-01-01

    Ground water is the primary source of water for domestic, municipal, and industrial use within the northwest section of Michigan's Lower Peninsula. Because of the importance of this resource, numerous communities including the city of Cadillac in Wexford County, Michigan, have begun local wellhead protection programs. In these programs, communities protect their ground-water resources by identifying the areas that contribute water to production wells, identifying potential sources of contamination, and developing methods to cooperatively manage and minimize threats to the water supply. The U.S. Geological Survey, in cooperation with the city of Cadillac, simulated regional ground-water flow and estimated areas contributing recharge and zones of transport to the production well field. Ground-water flow models for the Clam River watershed, in Wexford and Missaukee Counties, were developed using the U.S. Geological Survey modular three-dimensional finite-difference ground-water flow model (MODFLOW 2000). Ground-water flow models were calibrated using the observation, sensitivity, and parameter estimation packages of MODFLOW 2000. Ground-water-head solutions from calibrated flow models were used in conjunction with MODPATH, a particle-tracking program, to simulate regional ground-water flow and estimate areas contributing recharge and zones of transport to the Cadillac production-well field for a 10-year period. Model simulations match the conceptual model in that regional ground-water flow in the deep ground-water system is from southeast to northwest across the watershed. Areas contributing water were determined for the optimized parameter set and an alternate parameter set that included increased recharge and hydraulic conductivity values. Although substantially different hydrologic parameters (assumed to represent end-member ranges of realistic hydrologic parameters) were used in alternate numerical simulations, simulation results differ little in predictions of

  1. Ground-water resources of the alluvial aquifers in northeastern Larimer County, Colorado

    USGS Publications Warehouse

    Hurr, R.T.; Schneider, P.A.

    1977-01-01

    Ground water is a source of municipal, domestic, stock, and irrigation supply for most of northeastern Larimer County, Colo. A study of the alluvial aquifers in the northeastern part of the county was conducted to determine volume of water in storage, rate and location of ground-water withdrawals, and chemical quality of the water with particular attention to dissolved solids, hardness, sulfate, and selenium. There are 251 large-capacity wells in the study area. Well yields range from about 80 gpm (gallons per minute) to a little over 1,800 gpm. Total volume of water in storage is about 133,000 acre-feet--32 ,000 acre-feet in the alluvium of Buckeye terrace and 101,000 acre-feet in the valley-fill aquifer associated with Boxelder Creek. Ground-water withdrawals for irrigation are about 25,000 acre-feet annually. The municipal wells pumped 210 acre-feet in 1974. The factors affecting ground-water quality are the quality of applied irrigation water, the amount of water lost to evapotranspiration during irrigation, and, to a lesser degree, solution of soluble material in the alluvium and in the bedrock at the base of the alluvium. Ground water at the north end of the Buckeye terrace contains only about 300 mg/liter dissolved solids. Recharge is from surface water containing less than 90 mg/liter dissolved solids. Concentrations of all constituents increase downgradient to the south due to solution and evaporative concentration. (Woodard-USGS)

  2. Simulation of changes in water levels and ground-water flow in response to water-use alternatives in the Mud Lake area, eastern Snake River plain, eastern Idaho

    USGS Publications Warehouse

    Spinazola, Joseph M.

    1993-01-01

    Water users rely on surface and ground water to irrigate crops and maintain wildlife refuges in the 2,200-square-mile Mud Lake study area. Water managers need the ability to evaluate the effects of water-use changes on the future supply of surface and ground water. A five-layer, three-dimensional, finite-difference, numerical ground-water flow model, calibrated to assumed 1980 steady-state hydrologic conditions, was used to evaluate potential effects of seven water-use alternatives on ground-water levels and on losses from and gains to streams and lakes. The model was used to simulate steady-state water levels and ground-water flow for average 1980-90 hydrologic conditions and for seven water-use alternatives that represented changes from average 1980-90 conditions. Five alternatives represented reduced withdrawals from five different sets of wells, the sixth represented increased withdrawals in areas that could potentially support additional irrigation development, and the seventh represented reduced recharge in part of the study area where change from subirrigation to sprinkler irrigation is taking place. Simulated results from each alternative were compared with results for average 1980-90 conditions. Among the five water-use alternatives in which withdrawals from wells were reduced, simulated water levels were 0.1 to 40 feet higher than average 1980-90 conditions. Simulated stream and lake losses were as much as 4,700 acre-feet less and simulated gains were as much as 19,000 acre-feet greater in response to simulated water-level rises. Simulated underflow into the study area was as much as 8,200 acre-feet less and simulated underflow out of the study area was as much as 91,000 acre-feet greater. Simulated water-level declines were as great as 15 feet for the sixth alternative (increased withdrawals) and 10 feet for the seventh (reduced recharge). Simulated stream and lake losses were as much as 5,700 acre-feet greater and simulated gains were as much as 37

  3. Remediation of dichloromethane (DCM)-contaminated ground water

    SciTech Connect

    Flathman, P.E.; Jerger, D.E.; Woodhull, P.M. )

    1992-08-01

    This case history describes the physical and biological treatment of dichloromethane (DCM)-contaminated ground water following the rupture of an underground pipeline which contaminated an estimated 11,000 m[sup 3] (14,000 yd[sup 3]) of soil and ground water in the early fall of 1983. Air stripping DCM from recovered ground water was initiated and provided an estimated 97% reduction in the ground water concentration of DCM. When it became evident that physical treatment alone would no longer be effective in removing residual DCM from the ground water environment, the practice of air stripping DCM from recovered ground water was terminated. Biological treatment was initiated and provided greater than a 500,000-fold reduction in the ground water concentration of DCM. Biological treatment had far exceeded the ability of physical treatment along to remediate a ground water environment contaminated with a biodegradable contaminant. 14 refs., 12 figs., 4 tabs.

  4. EVALUATING THE EFFECTIVENESS OF GROUND WATER EXTRACTION SYSTEMS (JOURNAL)

    EPA Science Inventory

    The most common process for remediating contaminated ground water is extraction and treatment. Data from 19 ongoing and completed ground water extraction systems were collected and analyzed to evaluate the effectiveness of this process in achieving cleanup concentration goals for...

  5. Pesticides in Ground Water of Wyoming, 1995-2006

    USGS Publications Warehouse

    Eddy-Miller, Cheryl A.; Bartos, Timothy T.; Hallberg, Laura L.

    2009-01-01

    In 1991, members of local, State, and Federal governments, as well as industry and interest groups, formed the Ground-water and Pesticides Strategy Committee (GPSC) to prepare the State of Wyoming Generic Management Plan for Pesticides in Ground Water. Little existing information was available describing pesticide occurrence in ground water; therefore, statewide baseline ground-water sampling was considered a high priority by the GPSC. The GPSC identified 20 pesticides and degradates for baseline ground-water sampling (referred to herein as focal pesticides). Sampling focused on the State's most vulnerable ground water (Wyoming Ground-water and Pesticides Strategy Committee, 1999) as determined by Hamerlinck and Arneson (1998; fig. 1). Ground-water vulnerability is based on inherent sensitivity of the hydrogeology (such as a shallow water table or highly permeable aquifer materials) and overlying land use.

  6. Geology and ground-water resources of Dane County, Wisconsin

    USGS Publications Warehouse

    Cline, Denzel R.

    1965-01-01

    The purpose of the ground-water investigation of Dane County, Wis., was to determine the occurrence, movement, quantity, quality, and availability of ground water in the unconsolidated deposits and the underlying bedrock. The relationships between ground water and surface water were studied in general in Dane County and in detail in the Madison metropolitan area. An analysis was made of the hydrologic system of the Yahara River valley and of the effects of ground-water pumpage on that system.

  7. Ground-water resources in the vicinity of Cortland, Trumbull County, Ohio

    USGS Publications Warehouse

    Barton, G.J.; Wright, P.R.

    1997-01-01

    The city of Cortland lies on the southeast ern shoreline of the 12.3-square-mile Mosquito Creek Lake in Trumbull County, Ohio. Cortland relies upon public wells completed in the Cussewago Sandstone for potable water. The Cussewago Sandstone, the principal aquifer in the study area, is a subcrop of the glaciofluvial sediments in the lake; the unit dips gently towards the southeast. Thickness of the Cussewago Sandstone ranges from less than 20 feet in south-central Bazetta Township to 152 feet in Cortland. The Bedford Shale overlies and confines the Cussewago Sandstone and separates it hydraulically from the Berea Sandstone. The Bedford Shale and Berea Sandstone are not a prolific source of ground water. In places, the Bedford Shale was completely eroded away prior to deposition of the Berea Sandstone. Where the Bedford Shale is absent, such as at the City of Cortland North Well Field, the Berea Sandstone and Cussewago Sandstone are likely in hydraulic connection. Throughout most of the study area, the Cussewago Sandstone is a confined aquifer. Ground-water flow is to the east and southeast. Pumping at both Cortland well fields has created cones of depression in the potentiometric surface. These cones of depression cause a local reversal in ground-water flow immediately east of both well fields. The absence of detectable concentrations of tritium in water samples from wells completed in the Cussewago Sandstone at Cortland indicates that ground water predates the atmospheric nuclear testing of the 1950's. Ground water requires about 60 to 110 years to flow from the Cussewago Sandstone subcrop of the glaciofluvial sediments in the lake to the Cortland public-supply wells. A comparison of aquifer storage and pumpage in the study area shows that the Cussewago Sandstone receives adequate recharge to support current withdrawals by Cortland public-supply wells. In the immediate vicinity of Cortland- between Route 305 and the Bazetta-Mecca Town ship line and between the

  8. Ground-water flow in the Gulf Coast aquifer systems, south-central United States

    USGS Publications Warehouse

    Williamson, A.K.; Grubb, H.F.

    2001-01-01

    The Gulf Coast regional aquifer systems constitute one of the largest, most complicated, and most interdependent aquifer systems in the United States. Ground-water flow in a 230,000-square-mile area of the south-central United States was modeled for the effect of withdrawing freshwater at the rate of nearly 10 billion gallons per day in 1985 from regional aquifers in the Mississippi Embayment, the Texas coastal uplands, and the coastal lowlands aquifer systems. The 1985 rate of pumping was three times the average rate of recharge to the aquifers before development. The report also estimates the effects of even greater withdrawal rates in the aquifer systems. About two-thirds of the water in the aquifers is saline to brine, which complicates the modeling. Land subsidence due to water withdrawal also was modeled.

  9. Selected ground-water data for Yucca Mountain region, southern Nevada and eastern California, through December 1994

    SciTech Connect

    Westenburg, C.L.; La Camera, R.J.

    1996-07-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Site Characterization Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during studies to determine the potential suitability of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 36 sites, ground-water discharge at 6 sites, and groundwater withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are presented for calendar year 1994. Data collected prior to 1994 are graphically presented and data collected by other agencies (or as part of other programs) are included to further indicate variations of ground-water levels, discharges, and withdrawals through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented. The statistical summary includes the number of measurements, the maximum, minimum, and median water-level altitudes, and the average deviation of measured water-level altitudes for selected baseline periods and for calendar years 1992-94.

  10. Regional Analysis of Ground-Water Recharge

    USGS Publications Warehouse

    Flint, Lorraine E.; Flint, Alan L.

    2007-01-01

    A modeling analysis of runoff and ground-water recharge for the arid and semiarid southwestern United States was performed to investigate the interactions of climate and other controlling factors and to place the eight study-site investigations into a regional context. A distributed-parameter water-balance model (the Basin Characterization Model, or BCM) was used in the analysis. Data requirements of the BCM included digital representations of topography, soils, geology, and vegetation, together with monthly time-series of precipitation and air-temperature data. Time-series of potential evapotranspiration were generated by using a submodel for solar radiation, taking into account topographic shading, cloudiness, and vegetation density. Snowpack accumulation and melting were modeled using precipitation and air-temperature data. Amounts of water available for runoff and ground-water recharge were calculated on the basis of water-budget considerations by using measured- and generated-meteorologic time series together with estimates of soil-water storage and saturated hydraulic conductivity of subsoil geologic units. Calculations were made on a computational grid with a horizontal resolution of about 270 meters for the entire 1,033,840 square-kilometer study area. The modeling analysis was composed of 194 basins, including the eight basins containing ground-water recharge-site investigations. For each grid cell, the BCM computed monthly values of potential evapotranspiration, soil-water storage, in-place ground-water recharge, and runoff (potential stream flow). A fixed percentage of runoff was assumed to become recharge beneath channels operating at a finer resolution than the computational grid of the BCM. Monthly precipitation and temperature data from 1941 to 2004 were used to explore climatic variability in runoff and ground-water recharge. The selected approach provided a framework for classifying study-site basins with respect to climate and dominant recharge

  11. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 26 2014-07-01 2014-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  12. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 26 2011-07-01 2011-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  13. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 27 2012-07-01 2012-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  14. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 27 2013-07-01 2013-07-01 false Ground-water protection standard. 264... Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... constituents under § 264.93 detected in the ground water from a regulated unit do not exceed the...

  15. 40 CFR 258.51 - Ground-water monitoring systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... that ensures detection of ground-water contamination in the uppermost aquifer. When physical obstacles... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Ground-water monitoring systems. 258... CRITERIA FOR MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51...

  16. Ground water in Myrtle Creek - Glendale area, Douglas County, Oregon

    USGS Publications Warehouse

    Frank, F.J.

    1979-01-01

    The purpose of this report is to describe briefly the occurence of ground water and to present ground-water information that will help water users, public officials, and planners to determine the probability of obtaining adequate quanitities of good-quality ground water in the Myrtle Creek-Glendale area.

  17. Electrical-analog analysis of ground-water depletion in central Arizona

    USGS Publications Warehouse

    Anderson, T.W.

    1968-01-01

    The Salt River Valley and the lower Santa Cruz River basin are the two largest agricultural areas in Arizona. The extensive use of ground water for irrigation has resulted in the need for a thorough appraisal of the present and future ground-water resources. The ground-water reservoir provides 80 percent (3.2 million acre-feet) of the total annual water supply. The amount of water pumped greatly exceeds the rate at which the ground-water supply is being replenished and has resulted in water-level declines of as much as 20 feet per year in some places. The depletion problem is of economic importance because ground water will become more expensive as pumping lifts increase and well yields decrease. The use of electrical-analog modeling techniques has made it possible to predict future ground-water levels under conditions of continued withdrawal in excess of the rate of replenishment. The electrical system is a representation of the hydrologic system: resistors and capacitors represent transmissibility and storage coefficients. The analogy between the two systems is accepted when the data obtained from the model closely match the field data in this instance, measured water-level change since 1923. The prediction of future water-table conditions is accomplished by a simple extension of the pumping trends to determine the resultant effect on the regional water levels. The results of this study indicate the probable depths to water in central Arizona in 1974 and 1984 if the aquifer characteristics are accurately modeled and if withdrawal of ground water continues at the same rate and under the tame areal distribution as existed between 1958 and 1964. The greatest depths to water in 1984 will be more than 700 feet near Stanfield and more than 650 feet in Deer Valley and northeast of Gilbert. South of Eloy and northwest of Litchfield Park, a static water level of more than 550 feet is predicted. The total water-level decline in the 20-year period 1964-84 at the deepest

  18. Characterization of Climax granite ground water

    SciTech Connect

    Isherwood, D.; Harrar, J.; Raber, E.

    1982-08-01

    The Climax ground water fails to match the commonly held views regarding the nature of deep granitic ground waters. It is neither dilute nor in equilibrium with the granite. Ground-water samples were taken for chemical analysis from five sites in the fractured Climax granite at the Nevada Test Site. The waters are high in total dissolved solids (1200 to 2160 mg/L) and rich in sodium (56 to 250 mg/L), calcium (114 to 283 mg/L) and sulfate (325 to 1060 mg/L). Two of the samples contained relatively high amounts of uranium (1.8 and 18.5 mg/L), whereas the other three contained uranium below the level of detection (< 0.1 mg/L). The pH is in the neutral range (7.3 to 8.2). The differences in composition between samples (as seen in the wide range of values for the major constituents and total dissolved solids) suggest the samples came from different, independent fracture systems. However, the apparent trend of increasing sodium with depth at the expense of calcium and magnesium suggests a common evolutionary chemical process, if not an interconnected system. The waters appear to be less oxidizing with depth (+ 410 mV at 420 m below the surface vs + 86 mV at 565 m). However, with Eh measurements on only two samples, this correlation is questionable. Isotopic analyses show that the waters are of meteoric origin and that the source of the sulfate is probably the pyrite in the fracture-fill material. Analysis of the measured water characteristics using the chemical equilibrium computer program EQ3 indicates that the waters are not in equilibrium with the local mineral assemblage. The solutions appear to be supersaturated with respect to the mineral calcite, quartz, kaolinite, muscovite, k-feldspar, and many others.

  19. Appraisal of ground-water quality near wastewater-treatment facilities, Glacier National Park, Montana

    USGS Publications Warehouse

    Moreland, Joe A.; Wood, Wayne A.

    1982-01-01

    Water-level and water-quality data were collected from monitoring wells at wastewater-treatment facilities in Glacier National Park. Five additional shallow observation wells were installed at the Glacier Park Headquarters facility to monitor water quality in the shallow ground-water system. Water-level, water-quality, and geologic information indicate that some of the initial monitoring wells are not ideally located to sample ground water most likely to be affected by waste disposal at the sites. Small differences in chemical characteristics between samples from monitor wells indicate that effluent may be affecting ground-water quality but that impacts are not significant. Future monitoring of ground-water quality could be limited to selected wells most likely to be impacted by percolating effluent. Laboratory analyses for common ions could detect future impacts. (USGS)

  20. Work plan for ground water elevation data recorder installation at Riverton, Wyoming

    SciTech Connect

    Not Available

    1994-08-01

    The purpose of this document is to describe the work that will be performed and the procedures that will be followed during installation of ground water elevation data recorders (data loggers) at the Riverton, Wyoming, Uranium Mill Tailings Remedial Action (UMTRA) Project site. Previous investigations conducted at the Riverton site to date supports a preliminary determination regarding the selection of ground water remediation alternatives appropriate to this site. Although ground water modeling employing existing data indicates that a natural flushing strategy may be appropriate, additional site-specific data are needed to confirm the applicability and feasibility of this remedial option. The data loggers will be used to gather required time-dependent data to investigate the interaction between ground water and surface water in the area.

  1. Memorandum describing the geology and ground-water conditions in the vicinity of Simpsonville, Maryland

    USGS Publications Warehouse

    Otton, E.G.

    1955-01-01

    The study of the hydrology in the vicinity of Simpsonville was undertaken as a part of the ground-water investigations in cooperation with the Maryland Department of Geology, Mines and Water Resources. It provides ground-water data in addition to those already available, as a basis for a decision by the Maryland Water Resources Commission in regard to the application of an industrial laboratory to appropriate 200,000 gallons of ground water a day at a site about half a mile northwest of Simpsonville (approximately 12 miles southwest of Baltimore). Also, it supplements existing information on the occurrence of ground water in crystalline rocks of the type underlying the site, which are widespread in the Piedmont of Maryland and other States.

  2. FRACFLO. Two-Dimensional Ground Water Transport

    SciTech Connect

    Gureghian, A.B.

    1990-07-01

    FRACFLO computes the two-dimensional, space, time dependent, convective dispersive transport of a single radionuclide in an unbounded single or multiple parallel fracture system with constant aperture. It calculates the one-dimensional diffusive transport into the rock matrix as well as the mass flux and cumulative mass flux at any point in the fracture. Steady-state isothermal ground water flow and parallel streamlines are assumed in the fracture, and the rock matrix is considered to be fully saturated with immobile water. The model can treat a single or multiple finite patch source or a Gaussian distributed source subject to a step or band release mode.

  3. Geology and ground-water resources of Goshen County, Wyoming; Chemical quality of the ground water

    USGS Publications Warehouse

    Rapp, J.R.; Visher, F.N.; Littleton, R.T.; Durum, W.H.

    1957-01-01

    Goshen County, which has an area of 2,186 square miles, lies in southeastern Wyoming. The purpose of this study was to evaluate the ground-water resources of the county by determining the character, thickness, and extent of the waterbearing materials; the source, occurrence, movement, quantity, and quality of the ground water; and the possibility of developing additional ground water. The rocks exposed in the area are sedimentary and range in age from Precambrian to Recent. A map that shows the areas of outcrop and a generalized section that summarizes the age, thickness, physical character, and water supply of these formations are included in the report. Owing to the great depths at which they lie beneath most of the county, the formations older than the Lance formation of Late Cretaceous age are not discussed in detail. The Lance formation, of Late Cretaceous age, which consists mainly of beds of fine-grained sandstone and shale, has a maximum thickness of about 1,400 feet. It yields water, which usually is under artesian pressure, to a large number of domestic and stock wells in the south-central part of the county. Tertiary rocks in the area include the Chadron and Brule formations of Oligocene age, the Arikaree formation of Miocene age, and channel deposits of Pliocene age. The Chadron formation is made up of two distinct units: a lower unit of highly variegated fluviatile deposits that has been found only in the report area; and an upper unit that is typical of the formation as it occurs in adjacent areas. The lower unit, which ranges in thickness from a knife edge to about 95 feet, is not known to yield water to wells, but its coarse-grained channel deposits probably would yield small quantities of water to wells. The upper unit, which ranges in thickness from a knife edge to about 150 feet, yields sufficient quantities of water for domestic and stock uses from channel deposits of sandstone under artesian pressure. The Brule formation, which is mainly a

  4. Selected Ground-Water Data for Yucca Mountain Region, Southern Nevada and Eastern California, January 2000-December 2002

    SciTech Connect

    Locke, Glenn L.; La Camera, Richard J.

    2003-12-31

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during activities to determine the potential suitability or development of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 35 wells and a fissure (Devils Hole), ground-water discharge at 5 springs and a flowing well, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are tabulated from January 2000 through December 2002. Historical data on water levels, discharges, and withdrawals are graphically presented to indicate variations through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented for 1992–2002 to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the annual number of measurements, maximum, minimum, and median water-level altitudes, and average deviation of measured water-level altitudes compared to selected baseline periods. Baseline periods varied for 1985–93. At six of the seven wells in Jackass Flats, the median water levels for 2002 were slightly higher (0.3–2.4 feet) than for their respective baseline periods. At the remaining well, data for 2002 was not summarized statistically but median water-level altitude in 2001 was 0.7 foot higher than that in its baseline period.

  5. Selected Ground-Water Data of Yucca Mountain Region, Southern Nevada and Eastern California, January 2000-December 2002

    USGS Publications Warehouse

    Locke, Glenn L.; La Camera, Richard J.

    2003-01-01

    The U.S. Geological Survey, in support of the U.S. Department of Energy, Yucca Mountain Project, collects, compiles, and summarizes hydrologic data in the Yucca Mountain region. The data are collected to allow assessments of ground-water resources during activities to determine the potential suitability or development of Yucca Mountain for storing high-level nuclear waste. Data on ground-water levels at 35 wells and a fissure (Devils Hole), ground-water discharge at 5 springs and a flowing well, and total reported ground-water withdrawals within Crater Flat, Jackass Flats, Mercury Valley, and the Amargosa Desert are tabulated from January 2000 through December 2002. Historical data on water levels, discharges, and withdrawals are graphically presented to indicate variations through time. A statistical summary of ground-water levels at seven wells in Jackass Flats is presented for 1992-2002 to indicate potential effects of ground-water withdrawals associated with U.S. Department of Energy activities near Yucca Mountain. The statistical summary includes the annual number of measurements, maximum, minimum, and median water-level altitudes, and average deviation of measured water-level altitudes compared to selected baseline periods. Baseline periods varied for 1985-93. At six of the seven wells in Jackass Flats, the median water levels for 2002 were slightly higher (0.3-2.4 feet) than for their respective baseline periods. At the remaining well, data for 2002 was not summarized statistically but median water-level altitude in 2001 was 0.7 foot higher than that in its baseline period.

  6. Nicotine Withdrawal

    PubMed Central

    McLaughlin, Ian; Dani, John A.; De Biasi, Mariella

    2015-01-01

    An aversive abstinence syndrome manifests 4–24 h following cessation of chronic use of nicotine-containing products. Symptoms peak on approximately the 3rd day and taper off over the course of the following 3–4 weeks. While the severity of withdrawal symptoms is largely determined by how nicotine is consumed, certain short nucleotide polymorphisms (SNPs) have been shown to predispose individuals to consume larger amounts of nicotine more frequently—as well as to more severe symptoms of withdrawal when trying to quit. Additionally, rodent behavioral models and transgenic mouse models have revealed that specific nicotinic acetylcholine receptor (nAChR) subunits, cellular components, and neuronal circuits are critical to the expression of withdrawal symptoms. Consequently, by continuing to map neuronal circuits and nAChR subpopulations that underlie the nicotine withdrawal syndrome—and by continuing to enumerate genes that predispose carriers to nicotine addiction and exacerbated withdrawal symptoms—it will be possible to pursue personalized therapeutics that more effectively treat nicotine addiction. PMID:25638335

  7. Assessment of the hydraulic connection between ground water and the Peace River, west-central Florida

    USGS Publications Warehouse

    Lewelling, B.R.; Tihansky, A.B.; Kindinger, J.L.

    1998-01-01

    The hydraulic connection between the Peace River and the underlying aquifers along the length of the Peace River from Bartow to Arcadia was assessed to evaluate flow exchanges between these hydrologic systems. Methods included an evaluation of hydrologic and geologic records and seismic-reflection profiles, seepage investigations, and thermal infrared imagery interpretation. Along the upper Peace River, a progressive long-term decline in streamflow has occurred since 1931 due to a lowering of the potentiometric surface of the Upper Floridan aquifer by as much as 60 feet because of intensive ground-water withdrawals for phosphate mining and agriculture. Another effect from lowering the potentiometric surface has been the cessation of flow at several springs located near and within the Peace River channel, including Kissengen Spring, that once averaged a flow of about 19 million gallons a day. The lowering of ground-water head resulted in flow reversals at locations where streamflow enters sinkholes along the streambed and floodplain. Hydrogeologic conditions along the Peace River vary from Bartow to Arcadia. Three distinctive hydrogeologic areas along the Peace River were delineated: (1) the upper Peace River near Bartow, where ground-water recharge occurs; (2) the middle Peace River near Bowling Green, where reversals of hydraulic gradients occur; and (3) the lower Peace River near Arcadia, where ground-water discharge occurs. Seismic-reflection data were used to identify geologic features that could serve as potential conduits for surface-water and ground-water exchange. Depending on the hydrologic regime, this exchange could be recharge of surface water into the aquifer system or discharge of ground water into the stream channel. Geologic features that would provide pathways for water movement were identified in the seismic record; they varied from buried irregular surfaces to large-scale subsidence flexures and vertical fractures or enlarged solution conduits

  8. Determining optimum pumping rates for creation of hydraulic barriers to ground-water pollutant migration

    SciTech Connect

    Shafer, J.M.

    1984-04-01

    In certain ground-water flow regimes control of the migration of pollutants can be achieved by hydraulic barriers created by ground-water withdrawal and/or injection. However, for complicated flow domains and situations where multiple wells may be installed, the determination of pumping rates to achieve a pollution control objective can be difficult. A nonlinear programming (NLP) algorithm is coupled to a two-dimensional, steady-state, ground-water flow model and an advective transport model for determination of optimum pumping rates for creation of hydraulic barriers. This technique is a screening tool for the selection of pumping rates to be subsequently confirmed with more detailed simulation. Two example applications of this technique are presented. The first example shows how NLP can be used to determine pumping rates required to develop a stagnation point. Optimum pumping rates for eight wells arranged in a circular configuration are determined so as to reduce the ground-water velocity to near zero over a precise region within a nonhomogeneous aquifer. The second example involves the determination of optimum steady-state pumping rates for six wells in a nonhomogeneous flow domain where the objective is the control (i.e., steering) of the trajectory of a contaminant plume. 17 references, 10 figures, 5 tables.

  9. Ground-water resources of Tinian, Commonwealth of the Northern Mariana Islands

    USGS Publications Warehouse

    Gingerich, Stephen B.; Yeatts, Daniel S.

    2000-01-01

    Tinian, which lies in the western Pacific Ocean at latitude 15°N and longitude 145°W (fig. 1), is the second largest island (39.2 mi2) in the Commonwealth of the Northern Mariana Islands (CNMI). Fresh ground water is obtained from shallow wells that tap the surface of a freshwater lends found in an aquifer composed mainly of coralline limestone. The main water-supply well withdraws water with a chloride concentration ranging from 160 to 220 mg/L. Current (1999) pumping rates adequately supply the island residents but future demand are expected to be higher.. To better understand the ground-water resources of the island and to learn more about the hydrology of oceanic islands, the U.S. Geological Survey (USGS) entered into a cooperative study with the Municipality of Tinian. The objective of the study, conducted between 1990 and 1997, was to assess the ground-water resources of the is;land. This report presents some of the results of the study including a description of the island's geology and geography, the current land use, the water-production system, the thickness and arcal extent of the freshwater lens, the water-table configuration and directions of ground-water flow. The report also discusses the relation of the changes in water-table elevation to daily and seasonal changes in ocean level.

  10. Technical approach for the management of UMTRA ground water investigation-derived wastes

    SciTech Connect

    Not Available

    1994-02-01

    During characterization, remediation, or monitoring activities of the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project, ground water samples are collected to assess the extent and amount of waterborne contamination that might have come from the mill tailings. This sampling sometimes occurs in contaminated areas where ground water quality has been degraded. Ground water sampling activities may result in field-generated wastes that must be disposed of in a manner protective of human health and the environment. During ground water sampling, appropriate measures must be taken to dispose of presampling purge water and well development water that is pumped to flush out any newly constructed wells. Additionally, pumping tests may produce thousands of gallons of potentially contaminated ground water that must be properly managed. In addition to the liquid wastes, there is the potential for bringing contaminated soils to the ground surface during the drilling and installation of water wells in areas where the subsurface soils may be contaminated. These soils must be properly managed as well. This paper addresses the general technical approach that the UMTRA Project will follow in managing field-generated wastes from well drilling, development, sampling, and testing. It will provide guidance for the preparation of Technical Assistance Contractor (TAC) Standard Operating Procedures (SOP) for the management and disposal of field-generated wastes from ground water monitoring and remediation activities.

  11. Hydrogeology and simulation of ground-water flow in the aquifers underlying Belvidere, Illinois

    USGS Publications Warehouse

    Mills, Patrick C.; Nazimek, J.E.; Halford, K.J.; Yeskis, D.J.

    2002-01-01

    The U.S. Geological Survey investigated the ground-water-flow system and distribution of contaminants in the vicinity of Belvidere, Illinois, during 1992?2000. The study included the compilation, collection, and analyses of hydrogeologic and water-quality data and simulation of the ground-water-flow system. Hydrogeologic data include lithologic, stratigraphic, geophysical, hydraulic-property, water-level, ground-water withdrawal, and streamflow data. Water-quality data include analyses of water samples primarily for volatile organic compounds (VOC?s) and selectively for tritium and inorganic constituents. Data were collected from about 250 wells and 21 surfacewater sites. These data were used (1) to describe the hydrogeologic framework of the ground-waterflow system, preferential pathways and directions of ground-water movement and contaminant distribution, ground-water/surface-water relations, and the water budget and (2) to develop and calibrate the ground-water-flow model. The glacial drift (sand and gravel with some clay) and Galena-Platteville (fractured dolomite) aquifers and the sandstone aquifers of the Cambrian-Ordovician aquifer system compose the ground-water-flow system underlying Belvidere and vicinity. The Glenwood confining unit separates the Galena-Platteville aquifer from the underlying sandstone aquifers. The Galena- Platteville aquifer and confining unit may be absent in parts of the Troy Bedrock Valley, about 1.5 miles west of Belvidere. Throughout the study area, the Kishwaukee River and its tributaries seem to be gaining flow from shallow ground-water discharge. Potentiometric levels in the glacial drift and Galena-Platteville aquifers range from about 900 feet above sea level in the upland areas to 740 feet along the Kishwaukee River. Estimated horizontal hydraulic conductivity of the glacial drift aquifer ranges from about 0.13 to 280 feet per day. The Galena-Platteville aquifer is a dual-porosity unit with the greatest percentage of flow

  12. Science to Help Understand and Manage Important Ground-Water Resources

    USGS Publications Warehouse

    Nickles, James

    2008-01-01

    Throughout California, as pressure on water resources continues to grow, water-supply agencies are looking to the state?s biggest ?reservoir? ? its ground-water basins ? for supply and storage. To better utilize that resource, the Sweetwater Authority and other local partners, including the city of San Diego and Otay Water Districts, are working with the U.S. Geological Survey (USGS) to develop the first comprehensive study of the coastal ground-water resources of southern San Diego County. USGS research is providing the integrated geologic and hydrologic knowledge necessary to help effectively utilize this resource on a coordinated, regional basis. USGS scientists are building a real-time well-monitoring network and gathering information about how the aquifers respond to different pumping and recharge-management strategies. Real-time ground-water levels are recorded every hour and are viewable on a project web site (http://ca.water.usgs.gov/sandiego/index.html). Data from the wells are helping to define the geology and hydrogeology of the area, define ground-water quality, and assess ground-water levels. The wells also are strategi-cally placed and designed to be usable by the local agencies for decades to come to help manage surface-water and ground-water operations. Additionally, the knowledge gained from the USGS study will help local, state, and federal agencies; water purveyors; and USGS scientists to understand the effects of urbanization on the local surface-water, ground-water, and biological resources, and to better critique ideas and opportuni-ties for additional ground-water development in the San Diego area.

  13. Hydrology of the coastal springs ground-water basin and adjacent parts of Pasco, Hernando, and Citrus Counties, Florida

    USGS Publications Warehouse

    Knochenmus, Lari A.; Yobbi, Dann K.

    2001-01-01

    The coastal springs in Pasco, Hernando, and Citrus Counties, Florida consist of three first-order magnitude springs and numerous smaller springs, which are points of substantial ground-water discharge from the Upper Floridan aquifer. Spring flow is proportional to the water-level altitude in the aquifer and is affected primarily by the magnitude and timing of rainfall. Ground-water levels in 206 Upper Floridan aquifer wells, and surface-water stage, flow, and specific conductance of water from springs at 10 gaging stations were measured to define the hydrologic variability (temporally and spatially) in the Coastal Springs Ground-Water Basin and adjacent parts of Pasco, Hernando, and Citrus Counties. Rainfall at 46 stations and ground-water withdrawals for three counties, were used to calculate water budgets, to evaluate long-term changes in hydrologic conditions, and to evaluate relations among the hydrologic components. Predictive equations to estimate daily spring flow were developed for eight gaging stations using regression techniques. Regression techniques included ordinary least squares and multiple linear regression techniques. The predictive equations indicate that ground-water levels in the Upper Floridan aquifer are directly related to spring flow. At tidally affected gaging stations, spring flow is inversely related to spring-pool altitude. The springs have similar seasonal flow patterns throughout the area. Water-budget analysis provided insight into the relative importance of the hydrologic components expected to influence spring flow. Four water budgets were constructed for small ground-water basins that form the Coastal Springs Ground-Water Basin. Rainfall averaged 55 inches per year and was the only source of inflow to the Basin. The pathways for outflow were evapotranspiration (34 inches per year), runoff by spring flow (8 inches per year), ground-water outflow from upward leakage (11 inches per year), and ground-water withdrawal (2 inches per year

  14. Ground-water hydrology of the Mormon Island Crane Meadows Wildlife Area near Grand Island, Hall County, Nebraska

    USGS Publications Warehouse

    Hurr, T.R.

    1981-01-01

    The Platte River in south-central Nebraska flows generally eastward in a broad, flat valley. The river banks and many areas adjacent to the river support thick stands of cottonwood and willow trees. Brush, grass, pasture land, and cultivated fields occupy most of the remaining area. This is the habitat for many types of wildlife that live in the area or stop over in the area during annual migrations. Both sandhill cranes and whooping cranes are part of the annual migration. There is concern that water-management changes, such as surface-water diversions or ground-water withdrawals for irrigation, may alter the hydrologic environment of the wetland areas and be harmful to the wildlife habitat. In order to determine what affect changes in water management might have on ground-water levels in the wetland areas, detailed data were collected from Crane Meadows Wildlife Area, which is on an island in the Platte River near Grand Island, Nebr. Ground-water levels beneath the island respond to changes in river stage, to recharge from snowmelt and precipitation, and to evapotranspiration by riparian vegetation and from areas where the water table is close to the land surface. The data show that ground-water levels respond rapidly to changes in river stage--usually within 24 hours for distances up to 2,500 feet from the edge of the river. Thus changes in river stage due to changes in surface-water diversions will not have a long-term effect on ground-water levels. Changes in ground-water withdrawals will have the double effect of changing ground-water levels due to changes in drawdown and due to changes in river stage caused by the effects of pumping on river flow. These effects will develop slowly and be long lasting. (USGS)

  15. 40 CFR 144.87 - How does the identification of ground water protection areas and other sensitive ground water...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... existing motor vehicle waste disposal wells within your State. (b) Ground water protection areas. (1) For... area is complete every existing motor vehicle waste disposal well owner in that ground water protection.... Existing motor vehicle waste disposal well owners and operators within other sensitive ground water...

  16. 40 CFR 144.87 - How does the identification of ground water protection areas and other sensitive ground water...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... existing motor vehicle waste disposal wells within your State. (b) Ground water protection areas. (1) For... area is complete every existing motor vehicle waste disposal well owner in that ground water protection.... Existing motor vehicle waste disposal well owners and operators within other sensitive ground water...

  17. 40 CFR 144.87 - How does the identification of ground water protection areas and other sensitive ground water...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... apply to all existing motor vehicle waste disposal wells within your State. (b) Ground Water Protection... protection area is complete every existing motor vehicle waste disposal well owner in that ground water.... Existing motor vehicle waste disposal well owners and operators within other sensitive ground water...

  18. The ground-water system in southeastern Laramie County, Wyoming

    USGS Publications Warehouse

    Crist, Marvin A.; Borchert, William B.

    1972-01-01

    Increased development of irrigation wells in southeastern Laramie County, Wyo., has caused concern about the quantity of water available. Ground water from approximately 230 large-capacity wells is used to irrigate most of the 18,165 acres under irrigation. The purpose of this study is to provide more knowledge about the character of the aquifers, quantity of water in storage, rate of withdrawal, and the effect of withdrawals on streamflow. The area studied consists of about 400 square miles in southeastern Laramie County in the extreme southeast corner of Wyoming. The White River Formation of Oligocene age and alluvium of Quaternary age are the principal aquifers. The White River Formation is made up primarily of clay, silt, and fine sand. Secondary permeability in the White River Formation accounts for it being an important aquifer. The alluvium, which Includes terrace and flood-plain deposits, consists of sand and gravel that contain some lenses of silt and clay. Existence of secondary permeability in the White River Formation has been accepted for some time although the nature of the secondary permeability has been disputed. Examination of downhole conditions with a television camera during this study revealed openings in the formation that appeared to be similar to tubes or caverns. The openings were of various sizes and shapes but only a few appeared to be associated with fracturing. Solution activity in the formation probably is an important factor in the development of secondary permeability. The study area was divided into the Pine Bluffs-Egbert area and the Carpenter area. Ground-water movement in the Pine Bluffs-Egbert area is generally eastward into Nebraska; in the Carpenter area, movement is generally southward into Colorado. Pumpage from large-capacity wells in the Pine Bluffs-Egbert area was estimated to be about 21,790 acre-feet in 1971. Water levels exhibited a declining trend annually in some areas during the period of record. Data indicate that

  19. Hanford Site ground-water surveillance for 1989

    SciTech Connect

    Evans, J.C.; Bryce, R.W.; Bates, D.J.; Kemner, M.L.

    1990-06-01

    This annual report of ground-water surveillance activities provides discussions and listings of results for ground-water monitoring at the Hanford Site during 1989. The Pacific Northwest Laboratory (PNL) assesses the impacts of Hanford operations on the environment for the US Department of Energy (DOE). The impact Hanford operations has on ground water is evaluated through the Hanford Site Ground-Water Surveillance program. Five hundred and sixty-seven wells were sampled during 1989 for Hanford ground-water monitoring activities. This report contains a listing of analytical results for calendar year (CY) 1989 for species of importance as potential contaminants. 30 refs., 29 figs,. 4 tabs.

  20. Monitoring for pesticides in ground water in Nevada

    USGS Publications Warehouse

    Adams, Patricia A.; Moses, Charles W.; Bevans, Hugh E.

    1997-01-01

    Many pesticides designed to control weed encroachment, plant disease, and insect predation are used in agricultural and urban areas in the United States. Contamination of ground water by pesticides has increased over the last 20 years (U.S. Environmental Protection Agency, 1992). In 1985, the U.S. Environmental Protection Agency (USEPA) estimated the detection of at least 17 agricultural pesticides in the ground water of 23 states. By 1988, pesticides identified in ground water had increased to 46 in 26 states. To protect ground water from pesticide contamination, USEPA, through the Federal Fungicide Insecticide and Rodenticide Act (FIFRA), requires all states to institute a ground-water protection program.

  1. High Plains regional ground-water study

    USGS Publications Warehouse

    Dennehy, Kevin F.

    2000-01-01

    Over the last 25 years, industry and government have made large financial investments aimed at improving water quality across the Nation. Significant progress has been made; however, many water-quality concerns remain. In 1991, the U.S. Geological Survey (USGS) began implementing a full-scale National Water-Quality Assessment Program to provide consistent and scientifically sound information for managing the Nation's water resources. The goals of the NAWQA Program are to (1) describe current water-quality conditions for a large part of the Nation's freshwater streams and aquifers, (2) describe how water quality is changing over time, and (3) improve our understanding of the primary natural and human factors affecting water quality. Assessing the quality of water in every location in the Nation would not be practical; therefore, NAWQA Program studies are conducted within a set of areas called study units (fig. 1). These study units are composed of more than 50 important river and aquifer systems that represent the diverse geography, water resources, and land and water uses of the Nation. The High Plains Regional Ground-Water Study is one such study area, designed to address issues relevant to the High Plains Aquifer system while supplementing water-quality information collected in other study units across the Nation. Implementation of the NAWQA Program for the High Plains Regional Ground-Water Study area began in 1998.

  2. Ground-water models: Validate or invalidate

    USGS Publications Warehouse

    Bredehoeft, J.D.; Konikow, L.F.

    1993-01-01

    The word validation has a clear meaning to both the scientific community and the general public. Within the scientific community the validation of scientific theory has been the subject of philosophical debate. The philosopher of science, Karl Popper, argued that scientific theory cannot be validated, only invalidated. Popper’s view is not the only opinion in this debate; however, many scientists today agree with Popper (including the authors). To the general public, proclaiming that a ground-water model is validated carries with it an aura of correctness that we do not believe many of us who model would claim. We can place all the caveats we wish, but the public has its own understanding of what the word implies. Using the word valid with respect to models misleads the public; verification carries with it similar connotations as far as the public is concerned. Our point is this: using the terms validation and verification are misleading, at best. These terms should be abandoned by the ground-water community.

  3. Quality of ground water in Idaho

    USGS Publications Warehouse

    Yee, Johnson J.; Souza, William R.

    1987-01-01

    The major aquifers in Idaho are categorized under two rock types, sedimentary and volcanic, and are grouped into six hydrologic basins. Areas with adequate, minimally adequate, or deficient data available for groundwater-quality evaluations are described. Wide variations in chemical concentrations in the water occur within individual aquifers, as well as among the aquifers. The existing data base is not sufficient to describe fully the ground-water quality throughout the State; however, it does indicate that the water is generally suitable for most uses. In some aquifers, concentrations of fluoride, cadmium, and iron in the water exceed the U.S. Environmental Protection Agency's drinking-water standards. Dissolved solids, chloride, and sulfate may cause problems in some local areas. Water-quality data are sparse in many areas, and only general statements can be made regarding the areal distribution of chemical constituents. Few data are available to describe temporal variations of water quality in the aquifers. Primary concerns related to special problem areas in Idaho include (1) protection of water quality in the Rathdrum Prairie aquifer, (2) potential degradation of water quality in the Boise-Nampa area, (3) effects of widespread use of drain wells overlying the eastern Snake River Plain basalt aquifer, and (4) disposal of low-level radioactive wastes at the Idaho National Engineering Laboratory. Shortcomings in the ground-water-quality data base are categorized as (1) multiaquifer sample inadequacy, (2) constituent coverage limitations, (3) baseline-data deficiencies, and (4) data-base nonuniformity.

  4. Ground-water flow and ground- and surface-water interaction at the Weldon Spring quarry, St. Charles County, Missouri

    SciTech Connect

    Imes, J.L.; Kleeschulte, M.J.

    1997-12-31

    Ground-water-level measurements to support remedial actions were made in 37 piezometers and 19 monitoring wells during a 19-month period to assess the potential for ground-water flow from an abandoned quarry to the nearby St. Charles County well field, which withdraws water from the base of the alluvial aquifer. From 1957 to 1966, low-level radioactive waste products from the Weldon Spring chemical plant were placed in the quarry a few hundred feet north of the Missouri River alluvial plain. Uranium-based contaminants subsequently were detected in alluvial ground water south of the quarry. During all but flood conditions, lateral ground-water flow in the bedrock from the quarry, as interpreted from water-table maps, generally is southwest toward Little Femme Osage Creek or south into the alluvial aquifer. After entering the alluvial aquifer, the ground water flows southeast to east toward a ground-water depression presumably produced by pumping at the St. Charles County well field. The depression position varies depending on the Missouri River stage and probably the number and location of active wells in the St. Charles County well field.

  5. Status of ground-water resources at U.S. Navy Support Facility, Diego Garcia; summary of hydrologic and climatic data, January 1994 through September 1996

    USGS Publications Warehouse

    Torikai, J.D.

    1996-01-01

    This report describes the status of ground-water resources at U.S. Navy Support Facility, Diego Garcia. Data presented are from January 1994 through September 1996, with a focus on data from July through September 1996 (third quarter of 1996). A complete database of ground-water withdrawals and chloride-concentration records since 1985 is maintained by the U.S. Geological Survey. Total rainfall for the period July through September 1996 was 8.94 inches, which is 60 percent less than the mean rainfall of 22.23 inches for the period July through September. July and August are part of the annual dry season, while September is the start of the annual wet season. Ground-water withdrawal during July through September 1996 averaged 1,038,300 gallons per day. Withdrawal for the same 3 months in 1995 averaged 888,500 gallons per day. Ground-water withdrawals have steadily increased since about April 1995. At the end of September 1996, the chloride concentration of water from the elevated tanks at Cantonment and Air Operations were 68 and 150 milligrams per liter, respectively. The chloride concentration from all five production areas increased throughout the third quarter of 1996, and started the upward trend in about April 1995. Chloride concentration of ground water in monitoring wells at Cantonment and Air Operations also increased throughout the third quarter of 1996, with the largest increases from water in the deepest monitoring wells. Chloride concentrations have not been at this level since the dry season of 1994. A fuel-pipeline leak at Air Operations in May 1991 decreased total islandwide withdrawals by 15 percent. This lost pumping capacity is being offset by increased pumpage at Cantonment. Six wells do not contribute to the water supply because they are being used to hydraulically divert fuel migration away from water-supply wells by a program of ground-water withdrawal and injection.

  6. Assessment of ground water quality in a fractured aquifer under continue wastewater injection.

    PubMed

    Carrieri, C; Masciopinto, C

    2000-01-01

    Experimental studies have been carried out in a fractured coastal aquifer of the Salento Region (Nardò (Le), Italy), subject since 1991 to injection of 12,000 m3/d of treated municipal wastewater in a natural sink. The analytical parameters of ground water sampled in monitoring wells, have been compared before and after the injection started. The mound of water table (1.5 m), the reduction of seawater extent of 2 km and the spreading of pollutants injected were evaluated by means of mathematical model results. After ten years operation, the volume of the available resource for agricultural and drinking use has been increased, without notable decrease of the preexistent ground water quality. Moreover for preserving such resource from pollution, the mathematical model allowed the standards of wastewater quality for recharge to be identified. Around the sink, a restricted area was also defined with prohibition of withdrawals, to avoid infection and other risks on human health.

  7. A digital model for simulation of ground-water hydrology in the Houston area, Texas

    USGS Publications Warehouse

    Meyer, Walter R.; Carr, Jerry E.

    1979-01-01

    This report documents the construction and calibration of a digital model for the simulation of hydrologic conditions in the Chicot and Evangeline aquifers in the Houston area of southeastern Texas. The model is a five-layer finite-difference model, with a grid pattern of 63 x 67 nodes representing an area of 27,000 square miles, for simulation of three- dimensional ground-water flow. The hydrologic properties and processes modeled were ground-water withdrawals, transmissivities, storage coefficients of the aquifers and clays, quantity of water derived from storage in the clays, and vertical hydraulic conductivity and vertical leakage. The model, which simulates water-level declines, changes in storage in the clay layers, and land-surface subsidence, was calibrated by use of historical records from 1890 to 1975. It is very sensitive to variations in transmissivities and to variations in water-table and artesian storage. It is less sensitive to variations in clay storage.

  8. Preliminary survey of ground-water resources for Island County, Washington

    USGS Publications Warehouse

    Cline, D.R.; Jones, M.A.; Dion, N.P.; Whiteman, K.J.; Sapik, D.B.

    1982-01-01

    Increased ground-water withdrawals associated with the population increase in Island County have caused concern about ground-water availability and potential seawater intrusion. The most widespread and widely used aquifer lies near sea level. Locally, available data also indicate that one or more water-bearing zones lie above the sea-level aquifer. Pumpage in 1979 totaled about 1.67 billion gallons; about 90% was pumped from the sea-level aquifer. Most large producing wells in the county have pumping water levels near or below sea level, so that if pumping continued for a long enough time, seawater intrusion would result. Sampling of chloride concentrations in July 1978, April 1980, and August 1980 indicated problem areas mainly in northeastern and southern Camano Island and in central Whidbey Island. (USGS)

  9. A Numerical model to evaluate proposed ground-water allocations in southwest Kansas

    USGS Publications Warehouse

    Jorgensen, D.G.; Grubb, H.F.; Baker, C.H.; Hilmes, G.E.; Jenkins, E.D.

    1982-01-01

    A computer model was developed to assist the Southwest Kansas Groundwater Management District No. 3 in the evaluation of applications to appropriate ground water. The model calculated the drawdown due from a proposed well at all existing wells in the section of the proposed well and at all wells in the adjacent eight sections. The depletion expected in the 9-square-mile area due to all existing wells and the proposed well is computed and compared with allowable limits defined by the management district. An optional program permits the evaluation of allowable depletion for one or more townships. All options are designed to run interactively, thus allowing for immediate evaluation of proposed ground-water withdrawals. (USGS)

  10. Isotopic compositions and sources of nitrate in ground water from western Salt River Valley, Arizona

    USGS Publications Warehouse

    Gellenbeck, D.J.

    1994-01-01

    Isotopic and chemical compositions of ground water from western Salt River Valley near Phoenix, Arizona, were used to develop identification tech- niques for sources of nitrate in ground water. Four possible sources of nitrate were studied: dairies and feedlots, sewage-treatment plants, agricultural activities, and natural source. End members that represent these sources were analyzed for a variety of chemical and isotopic constituents; contents of the end-member and the ground water were compared to identify nitrate from these sources. Nitrate from dairies and feedlots was identified by delta 15N values higher than +9.0 per mil. Nitrate from sewage treatment plants was identified by some chemical constituents and values of delta 15N, delta 34S, delta 7Li, and delta 11B that were lighter than the values determined for ground water not affected by sewage-treatment plants. Nitrate from agricultural activities was identified by delta 15N, 3H, and delta 34S compositions. Natural nitrate derived from decomposing plants and accumulated by biological fixation was identified by delta 15N values that range between +2 and +8 per mil. In addition to identifying nitrate sources, some chemical and isotopic charabteristics of ground water were determined on the basis of data collected during this study. Concentrations of major ions, lithium, and boron and delta 7Li, delta 11B, 3H, delta D, and delta 18O data identify ground water in different geographic regions in the study area. These differences probably are related to different sources of ground water, geochemical processes, or geologic deposits. The Luke salt body and a geothermal anomaly alter the chemical and isotopic content of some ground water.

  11. Ground-Water Resources of Saipan, Commonwealth of the Northern Meriana Islands

    USGS Publications Warehouse

    Carruth, Robert L.

    2003-01-01

    Introduction Saipan has an area of 48 mi2 and is the largest of the 14 islands in the Commonwealth of the Northern Mariana Islands (CNMI). The island is formed by volcanic rocks overlain by younger limestones. The island is situated in the western Pacific Ocean at latitude 15?12'N and longitude 145?45'E, about 3,740 mi west-southwest of Honolulu and midway between Japan and New Guinea (fig. 1). The climate on Saipan is classified as tropical marine with an average temperature of 80?F. The natural beauty of the island and surrounding waters are the basis for a growing tourist-based economy. The resulting rapid development and increases in resident and tourist populations have added stresses to the island's limited water supplies. Freshwater resources on Saipan are not readily observable because, aside from the abundant rainfall, most freshwater occurs as ground water. Fresh ground water is found in aquifers composed mainly of fragmental limestones. About 90 percent of the municipal water supply comes from 140 shallow wells that withdraw about 11 Mgal/d. The chloride concentration of water withdrawn from production wells ranges from less than 100 mg/L for wells in the Akgak and Capital Hill well fields, to over 2,000 mg/L from wells in the Puerto Rico, Maui IV, and Marpi Quarry well fields. The chloride concentrations and rates of ground-water production are not currently adequate for providing island residents with a potable 24-hour water supply and future demands are expected to be higher. To better understand the ground-water resources of the island, and water resources on tropical islands in general, the U.S. Geological Survey (USGS) entered into a cooperative program with the Commonwealth Utilities Corporation (CUC). The objective of the program, initiated in 1989, is to assess the ground-water resources of Saipan and to make hydrologic information available to the CUC in support of their ongoing efforts to improve the quality and quantity of the municipal water

  12. Distribution, Origin, and Realtions to Flow of Salty Ground Water Along the Western Margin of the Chesapeake Bay Impact Structure in Eastern Virginia

    NASA Astrophysics Data System (ADS)

    McFarland, R.; Bruce, S.

    2002-05-01

    The Chesapeake Bay impact structure closely coincides with parts of some aquifers in eastern Virginia that contain saltwater as much as 30 miles landward of the coast. The impact structure has thereby been inferred to play some role in controlling the presence of this "inland saltwater wedge", which formed under unstressed conditions prior to present-day ground-water withdrawals. That the impact severely disrupted the previously stratified sediments casts doubt on conceptualizations of a regionally contiguous, vertically layered system of aquifers and confining units. In addition, large and increasing ground-water withdrawals have resulted in continuing water-level declines and altered flow directions that create the potential for saltwater intrusion. Hence, the origin and emplacement of the saltwater must be known to predict its reaction to stresses being placed upon the flow system. Specific conductances and concentrations of chloride in ground water along the western margin of the impact structure reflect a transitional interface between freshwater to the west and seawater to the east that coincides aerially with the margin of the impact structure. Ratios of bromide to chloride and chlorine-36 to total chloride, and of stable hydrogen and oxygen isotopes, indicate chloride to have originated primarily from mixing of freshwater and seawater across the interface. In addition, deep ground water east of the interface having specific conductances which exceed that of seawater likely resulted from partial evaporation of seawater, either (1) in restricted coastal environments under arid conditions, (2) by rapid vaporization caused by the impact event, and (or) (3) by residual heat and associated hydrothermal activity following the impact. Mixing of freshwater and seawater has been theorized to take place in a "differential flushing" manner that left residual seawater to form the saltwater wedge. Seawater emplaced during inundation of the land surface persisted around

  13. Simulation of projected water demand and ground-water levels in the Coffee Sand and Eutaw-McShan aquifers in Union County, Mississippi, 2010 through 2050

    USGS Publications Warehouse

    Hutson, Susan S.; Strom, E.W.; Burt, D.E.; Mallory, M.J.

    2000-01-01

    Ground water from the Eutaw-McShan and the Coffee Sand aquifers is the major source of supply for residential, commercial, and industrial purposes in Union County, Mississippi. Unbiased, scientifically sound data and assessments are needed to assist agencies in better understanding and managing available water resources as continuing development and growth places more stress on available resources. The U.S. Geological Survey, in cooperation with the Tennessee Valley Authority, conducted an investigation using water-demand and ground-water models to evaluate the effect of future water demand on groundwater levels. Data collected for the 12 public-supply facilities and the self-supplied commercial and industrial facilities in Union County were used to construct water-demand models. The estimates of water demand to year 2050 were then input to a ground-water model based on the U.S. Geological Survey finite-difference computer code, MODFLOW. Total ground-water withdrawals for Union County in 1998 were estimated as 2.85 million gallons per day (Mgal/d). Of that amount, municipal withdrawals were 2.55 Mgal/d with about 1.50 Mgal/d (59 percent) delivered to residential users. Nonmunicipal withdrawals were 0.296 Mgal/d. About 80 percent (2.27 Mgal/d) of the total ground-water withdrawal is produced from the Eutaw-McShan aquifer and about 13 percent (0.371 Mgal/d) from the Coffee Sand aquifer. Between normal- and high-growth conditions, total water demand could increase from 72 to 131 percent (2.9 Mgal/d in 1998 to 6.7 Mgal/d in year 2050) with municipal demand increasing from 77 to 146 percent (2.6 to 6.4 Mgal/d). Increased pumping to meet the demand for water was simulated to determine the effect on water levels in the Coffee Sand and Eutaw- McShan aquifers. Under baseline-growth conditions, increased water use by year 2050 could result in an additional 65 feet of drawdown in the New Albany area below year 2000 water levels in the Coffee Sand aquifer and about 120 feet of

  14. Ground Water at Grant Village Site, Yellowstone National Park, Wyoming

    USGS Publications Warehouse

    Gordon, Ellis D.; McCullough, Richard A.; Weeks, Edwin P.

    1961-01-01

    On behalf of the National Park Service, the U.S. Geological Survey during the summer of 1959 made a study of ground-water conditions in the area of the Grant Village site, along the shore of the West Thumb of Yellowstone Lake, 1 to 2 miles south of the present facilities at West Thumb. The water supply for the present development at West Thumb is obtained from Duck Lake, but the quantity of water available from this source probably will be inadequate for the planned development at Grant Village. During the investigation, 11 auger holes were bored and 6 test wells were drilled. Aquifer tests by pumping and bailing methods were made at two of the test wells. All material penetrated in the auger holes and test wells is of Quaternary age except the welded tuff of possible Pliocene age that was penetrated in the lower part of test well 4. Small to moderate quantities of water were obtained from the test wells in the area. Test well 2 yielded 35 gpm (gallons per minute) at a temperature of nearly 100 deg F. Test well 6 yielded about 15 gpm at a temperature of 48 deg F. The yield of this well might be increased by perforation of additional sections of casing, followed by further development of the well. Water from the other four test wells was of inadequate quantity, too highly mineralized, or too warm to be effectively utilized. Most of the ground water sampled had high concentrations of silica and iron, and part of the water was excessively high in fluoride content. Otherwise, the ground water was of generally suitable quality for most uses. The most favorable area for obtaining water supplies from wells is near the lakeshore, where a large part of the water pumped would be ground-water flow diverted from its normal discharge into the lake. Moderate quantities of relatively cool water of fairly good quality may be available near the lakeshore between test wells 5 and 6 and immediately east of test well 6.

  15. Ground-Water Quality and Potential Effects of Individual Sewage Disposal System Effluent on Ground-Water Quality in Park County, Colorado, 2001-2004

    USGS Publications Warehouse

    Miller, Lisa D.; Ortiz, Roderick F.

    2007-01-01

    In 2000, the U.S. Geological Survey, in cooperation with Park County, Colorado, began a study to evaluate ground-water quality in the various aquifers in Park County that supply water to domestic wells. The focus of this study was to identify and describe the principal natural and human factors that affect ground-water quality. In addition, the potential effects of individual sewage disposal system (ISDS) effluent on ground-water quality were evaluated. Ground-water samples were collected from domestic water-supply wells from July 2001 through October 2004 in the alluvial, crystalline-rock, sedimentary-rock, and volcanic-rock aquifers to assess general ground-water quality and effects of ISDS's on ground-water quality throughout Park County. Samples were analyzed for physical properties, major ions, nutrients, bacteria, and boron; and selected samples also were analyzed for dissolved organic carbon, human-related (wastewater) compounds, trace elements, radionuclides, and age-dating constituents (tritium and chlorofluorocarbons). Drinking-water quality is adequate for domestic use throughout Park County with a few exceptions. Only about 3 percent of wells had concentrations of fluoride, nitrate, and (or) uranium that exceeded U.S. Environmental Protection Agency national, primary drinking-water standards. These primary drinking-water standards were exceeded only in wells completed in the crystalline-rock aquifers in eastern Park County. Escherichia coli bacteria were detected in one well near Guffey, and total coliform bacteria were detected in about 11 percent of wells sampled throughout the county. The highest total coliform concentrations were measured southeast of the city of Jefferson and west of Tarryall Reservoir. Secondary drinking-water standards were exceeded more frequently. About 19 percent of wells had concentrations of one or more constituents (pH, chloride, fluoride, sulfate, and dissolved solids) that exceeded secondary drinking-water standards

  16. MODFLOW-2005 : the U.S. Geological Survey modular ground-water model--the ground-water flow process

    USGS Publications Warehouse

    Harbaugh, Arlen W.

    2005-01-01

    This report presents MODFLOW-2005, which is a new version of the finite-difference ground-water model commonly called MODFLOW. Ground-water flow is simulated using a block-centered finite-difference approach. Layers can be simulated as confined or unconfined. Flow associated with external stresses, such as wells, areal recharge, evapotranspiration, drains, and rivers, also can be simulated. The report includes detailed explanations of physical and mathematical concepts on which the model is based, an explanation of how those concepts are incorporated in the modular structure of the computer program, instructions for using the model, and details of the computer code. The modular structure consists of a MAIN Program and a series of highly independent subroutines. The subroutines are grouped into 'packages.' Each package deals with a specific feature of the hydrologic system that is to be simulated, such as flow from rivers or flow into drains, or with a specific method of solving the set of simultaneous equations resulting from the finite-difference method. Several solution methods are incorporated, including the Preconditioned Conjugate-Gradient method. The division of the program into packages permits the user to examine specific hydrologic features of the model independently. This also facilitates development of additional capabilities because new packages can be added to the program without modifying the existing packages. The input and output systems of the computer program also are designed to permit maximum flexibility. The program is designed to allow other capabilities, such as transport and optimization, to be incorporated, but this report is limited to describing the ground-water flow capability. The program is written in Fortran 90 and will run without modification on most computers that have a Fortran 90 compiler.

  17. Model of tritium dispersion by ground water

    NASA Astrophysics Data System (ADS)

    Golubev, A. V.; Mavrin, S. V.; Sten'gach, A. V.

    2000-07-01

    A three-dimensional model of ground-water contamination in the zone of a steady source of tritium is presented. The model is oriented toward long-term modeling of contamination (for up to several decades) on a large area (of up to several hundred square kilometers) where the contaminant arrives through the roof of the aquiferous stratum by infiltration. The three-dimensional equation of convective diffusion is solved numerically by the method of splitting. The convective component is calculated by the method of particles. The dispersion component of the transfer is calculated using the finite-difference method. A transformation of the vertical coordinate is introduced. A solution of the model problem is presented and an interpretation of the results is given.

  18. Two-Dimensional Ground Water Transport

    1992-03-05

    FRACFLO computes the two-dimensional, space, time dependent, convective dispersive transport of a single radionuclide in an unbounded single or multiple parallel fracture system with constant aperture. It calculates the one-dimensional diffusive transport into the rock matrix as well as the mass flux and cumulative mass flux at any point in the fracture. Steady-state isothermal ground water flow and parallel streamlines are assumed in the fracture, and the rock matrix is considered to be fully saturatedmore » with immobile water. The model can treat a single or multiple finite patch source or a Gaussian distributed source subject to a step or band release mode.« less

  19. Hydrogeology and effects of landfills on ground-water quality, southern Franklin County, Ohio

    USGS Publications Warehouse

    De Roche, J.T.

    1985-01-01

    Hydrogeology and water quality were evaluated near five land-fills along a 5-mile segment of the Scioto River valley south of Columbus, Ohio. Heterogenous surficial deposits o sand, gravel, and till up to 160 feet thick are hydraulically connected to the underlying Devonian limestone, the landfills and Scioto River, which has been leveed with 12 to 35 feet of refuse. Ground-water withdrawals caused a maximum 21-foot decline in ground-water levels from 1979 to 1982. The study reach of Scioto River within the influence of ground-water pumping is a losing stream, except for s small segment adjacent to one landfill. Analysis of variance indicated significant difference in ground-water quality between wells upgradient of landfills, down-gradient of landfills, and wells penetrating refuse. Elevated specific conductance and concentrations of total dissolved solids, ammonia, carbon dioxide, and dissolved organic carbon in water from wells downgradient from and penetrating landfills indicate leachate production and migration is occurring. Analysis of bed-material samples from Scioto River and Scioto Big Run revealed concentrations of polynuclear aromatic hydrocarbons ranging from 220 to 9,440 micograms per kilogram of sediment (?g/kg) and concentrations of toxic metals ranging from 1 to 720 ?g/kg. Samples from an upstream control station on Scioto River contained no organic compounds and lower concentrations of metals (ranging from 1 to 260 ?g/kg). Because of multiple land uses within the study area, organic compounds recovered from the streamed sediments cannot be attributed to any single source. The generation of hydrogen sulfide and methane gases, presence of a zone of increased hardness, elevated concentrations of common ionic species, and dominance of ammonia over other nitrogen species indicate that leachate is being produced and its migrating from four landfills and the river levee. Based on hydraulic relationships between ground water and surface water, it is highly

  20. A ground-water-quality monitoring program for Nevada

    USGS Publications Warehouse

    Nowlin, Jon O.

    1986-01-01

    A program was designed for the systematic monitoring of ground-water quality in Nevada. Basic hydrologic and water-quality principles are discussed in the formulation of a rational approach to developing a statewide monitoring program. A review of ground-water monitoring efforts in Nevada through 1977 indicates that few requirements for an effective statewide program are being met. A suggested program has been developed that consists of five major elements: (1) A Background-Quality Network to assess the existing water quality in Nevada aquifers, (2) a Contamination Source Inventory of known or potential threats to ground-water quality, (3) Surveillance Networks to monitor ground-water quality in selected hydrographic areas, (4) Intensive Surveys of individual instances of known or potential ground-water contamination, and (5) Ground-Water Data File to manage data generated by the other monitoring elements. Two indices have been developed to help assign rational priorities for monitoring ground water in the 255 hydrographic areas of Nevada: (1) A Hydrographic-Area Priority Index for surveillance monitoring, and (2) A Development-Potential Index for background monitoring of areas with little or no current development. Requirements for efficient management of data from ground-water monitoring are discussed and the three major systems containing Nevada ground-water data are reviewed. More than 11,000 chemical analyses of ground water have been acquired from existing systems and incorporated into a prototype data base.

  1. Ground-water resources of the Clatsop Plains sand-dune area, Clatsop County, Oregon

    USGS Publications Warehouse

    Frank, F.J.

    1970-01-01

    Although the average annual precipitation of the Clatsop Plains is 78.5 inches, the area is not without problems of water supply. The Clatsop Plains area ix underlain by Tertiary bedrock of low permeability that stores and yields small quantities of ground water, which may be of poor chemical quality. This Tertiary bedrock furnishes only minor ground-water discharge to maintain the base flow of streams. The flow of rivers and creeks, normally abundant during the wet season, decreases greatly during the dry summer months. The lowlands are overlain by extensive deposits of dune and beach sand. The dune sand is permeable and can absorb and store, as fresh water, a large percentage of the annual precipitation. In the central part of the dune area, the saturated thickness of the sand ranges from 95 to more than 150 feet. Most of the ground water in the sand discharges to the ocean through beach-line seeps and underflow. Much of the water now being discharged to the ocean could be recovered by pumping from properly located, designed, and constructed wells. Three test wells drilled as part of this study are capable of yielding 100 gallons per minute although they are equipped with only short lengths of well screen. It is estimated that 2,500 acre-feet of ground water per year per square mile of area may be available for withdrawal in the 10 square mile area that is most favorable for development. The water from the dune sand is soft to moderately hard, has a low chloride concentration, and is of generally good chemical quality; however, at places it is weakly acidic and contains sufficient dissolved iron to make iron removal necessary for some uses. Ground water from shallow depths beneath a few swampy low-lying areas is brown and contains excessive concentrations of iron.

  2. Availability of ground water in Lyon County, Minnesota

    USGS Publications Warehouse

    Rodis, Harry G.

    1961-01-01

    The county is divided into areas of ground-water availability based on the quality and quantity of ground water available from the different geologic units. The glacial drift which covers all of the area, yields very hard water from sands and gravels occurring in melt-water channel deposits or as small, isolated melt-water bodies. Wells in the drift commonly yield from 2 to 30 gpm (gallons per minute), but sustained yields of as much as 500 gpm are obtained in areas where thick melt-water channel deposits occur. Cretaceous strata underlie about two-thirds of the county and yield water from poorly consolidated sandstone, The water ranges in hardness from soft to very hard and is sometimes high in chloride content. Wells in Cretaceous strata commonly yield from 2 to 7 gpm; however, in areas where the sandstone is in contact with the underlying weathered granite, sustained yields of as much as 75 gpm are obtained. The geographic and stratigraphic distribution of the geologic units suggests that additional water supplies may be available from Pleistocene and Cretaceous strata in areas not yet fully explored.

  3. Simulating ground water-lake interactions: Approaches and insights

    USGS Publications Warehouse

    Hunt, R.J.; Haitjema, H.M.; Krohelski, J.T.; Feinstein, D.T.

    2003-01-01

    Approaches for modeling lake-ground water interactions have evolved significantly from early simulations that used fixed lake stages specified as constant head to sophisticated LAK packages for MODFLOW. Although model input can be complex, the LAK package capabilities and output are superior to methods that rely on a fixed lake stage and compare well to other simple methods where lake stage can be calculated. Regardless of the approach, guidelines presented here for model grid size, location of three-dimensional flow, and extent of vertical capture can facilitate the construction of appropriately detailed models that simulate important lake-ground water interactions without adding unnecessary complexity. In addition to MODFLOW approaches, lake simulation has been formulated in terms of analytic elements. The analytic element lake package had acceptable agreement with a published LAK1 problem, even though there were differences in the total lake conductance and number of layers used in the two models. The grid size used in the original LAK1 problem, however, violated a grid size guideline presented in this paper. Grid sensitivity analyses demonstrated that an appreciable discrepancy in the distribution of stream and lake flux was related to the large grid size used in the original LAK1 problem. This artifact is expected regardless of MODFLOW LAK package used. When the grid size was reduced, a finite-difference formulation approached the analytic element results. These insights and guidelines can help ensure that the proper lake simulation tool is being selected and applied.

  4. Water resources data, Idaho, 2003; Volume 3. Ground water records

    USGS Publications Warehouse

    Campbell, A.M.; Conti, S.N.; O'Dell, I.

    2003-01-01

    Water resources data for the 2003 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 208 stream-gaging stations and 14 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 50 stream-gaging stations and partial record sites, 3 lakes sites, and 398 groundwater wells; and water levels for 427 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

  5. Water resources data, Idaho, 2004; Volume 3. Ground water records

    USGS Publications Warehouse

    Campbell, A.M.; Conti, S.N.; O'Dell, I.

    2005-01-01

    Water resources data for the 2004 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 209 stream-gaging stations and 8 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 39 stream-gaging stations and partial record sites, 18 lakes sites, and 395 groundwater wells; and water levels for 425 observation network wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

  6. Ground water in the vicinity of Capulin, New Mexico

    USGS Publications Warehouse

    Hart, D.L.; Smith, Christian

    1979-01-01

    The alluvial deposits within a closed basin near Capulin, New Mexico, are estimated to have 189,000 acre-feet of water in storage. These deposits have an estimated average transmissivity of 400 feet squared per day and represent the major source of ground water. Well yields range from a few gallons per minute to as much as 900 gallons per minute, with average potential yields ranging from about 100 to 200 gallons per minute in areas of greatest saturated thickness. Additional large quantities of water are available for short-term supplies from the saturated basaltic cinders west and northwest of the town of Capulin. Wells completed in the cinders reportedly have produced as much as 2,000 gallons per minute. The chemical quality of water in the alluvium and cinder aquifers appears to be chemically satisfactory for municipal use. The ground water in storage is sufficient to supplement Raton, New Mexico 's water needs to the year 2030 at the water demand rate projected by the Bureau of Reclamation. (Woodard-USGS)

  7. Ground-water data in Orange County and adjacent counties, Texas, 1985-90

    USGS Publications Warehouse

    Kasmarek, Mark C.

    1999-01-01

    The lower unit of the Chicot aquifer is a major source of freshwater for Orange County, Texas. In 1989, the average rate of ground-water withdrawal from the lower unit of the Chicot aquifer in Orange County for municipal and industrial use was 13.8 million gallons per day, a substantial decrease from the historical high of 23.1 million gallons per day in 1972. The average withdrawal for industrial use decreased substantially from 14.4 million gallons per day during 1963?84 to 6.9 million gallons per day during 1985?89. The average withdrawal for municipal use during 1985?89 was 6.8 million gallons per day, similar to the average withdrawal of 5.8 million gallons per day during 1963?84. Water levels in wells in most of the study area rose during 1985?90. The largest rise in water levels was more than 10 feet in parts of Orange and Pinehurst, north of site B (one of three areas of ground-water withdrawal for industrial use), while the largest decline in water levels was a localized decline of more than 60 feet at site C in south-central Orange County (also an area of withdrawal for industrial use). Chemical analyses of ground-water samples from the lower Chicot aquifer during 1985?90 indicate that the aquifer contained mostly freshwater (dissolved solids concentrations less than 1,000 milligrams per liter). Dissolved chloride concentrations remained relatively constant in most wells during 1985?90 but could vary greatly between wells within short distances. Saline-water encroachment continued to occur during 1985?89 but at a slower rate than in the 1970s and early 1980s. On the basis of chemical data collected during 1985?89, a relation was determined between specific conductance and dissolved chloride concentration that can be used to estimate dissolved chloride by multiplying the specific conductance by different factors for low or high conductances.

  8. Problems of rising ground-water levels in urban areas with special reference to the Louisville, Kentucky area

    USGS Publications Warehouse

    Whitesides, D.V.; Faust, R.J.; Zettwoch, D.D.

    1983-01-01

    Rising ground-water levels are a problem for cities such as San Bernadino, California; Greely and Fort Collins, Colorado; New York City boroughs of Brooklyn and Queens; and Louisville, Kentucky. Ground-water levels showed a steeply rising trend in the alluvial aquifer underlying Louisville during the early and middle 1970 's in response to above average precipitation and a decrease in ground-water withdrawals. This rising trend flattened in 1979 and the water levels are stabilizing at 25 to 45 feet below land surface in the downtown area. Basements are generally 20 to 25 feet below land surface and some utility lines are as much as 40 feet below land surface in this area. Because of the shallow depth to water, any resumption of the upward trend would require preventive measures such as selective dewatering to avoid damage to some structures. (USGS)

  9. Preliminary report on ground water in the Michaud Flats Project, Power County, Idaho

    USGS Publications Warehouse

    Stewart, J.W.; Nace, Raymond L.; Deutsch, Morris

    1952-01-01

    The Michaud Flats Project area, as here described, includes about 65 square miles in central Power County, south of the Snake River in the southeastern Snake River Plain of Idaho. The principal town and commercial center of the area is American Falls. The immediate purpose of work in the area by the U.S. Geological Survey was to investigate the possibility of developing substantial quantities of ground water for irrigating high and outlying lands in the proposed Michaud Flats Project area of the U.S. Bureau of Reclamation. Initial findings are sufficiently favorable to warrant comprehensive further investigation. Advanced study would assist proper utilization of ground-water resources and would aid ultimate evaluation of total water resources available in the area. About 10,000 acres of low-lying lands in the Michaud Flats project could be irrigated with water from the Snake River under a low-line distribution system involving a maximum pumping lift of about 200 feet above the river. An additional larger area of high and outlying lands is suitable for irrigation with water pumped from wells. If sufficient ground water is economically available, the expense of constructing and operating a costly highline distribution system for surface water could be saved. Reconnaissance of the ground-water geology of the area disclosed surface outcrops of late Cenozoic sedimentary, pyroclastic, and volcanic rocks. Well logs and test borings show that similar materials are present beneath the land surface in the zone of saturation. Ground water occurs under perched, unconfined, and confined (artesian) conditions, but the aquifers have not been adequately explored. Existing irrigation wells, 300 feet or less in depth, yield several hundred to 1,400 gallons of water a minute, with pumping drawdowns of 6 to 50 feet, and perhaps more. A few wells have been pumped out at rates of less than 800 gallons a minute. Scientific well-construction and development methods would lead to more

  10. Development of Ground Water in the Houston District, Texas, 1970-1974

    USGS Publications Warehouse

    Gabrysch, R.K.

    1980-01-01

    Total withdrawals of ground water in the Houston district increased 9 percent from about 488 million gallons per day (21.4 cubic meters per second) in 1970 to about 532 million gallons per day (23.3 cubic meters per second) in 1974. The average annual rate of increase from 1960 to 1969 was about 6.3 percent. During 1970-74, increases in pumpage occurred in the Houston, Katy, and NASA areas; decreases occurred in the Pasadena and Alta Lorna areas; and the pumpage in the Baytown-La Porte and Texas City areas remained almost constant.

  11. Baseline risk assessment of ground water contamination at the uranium mill tailings site near Durango, Colorado. Revision 1

    SciTech Connect

    1995-09-01

    For the UMTRA Project site located near Durango, Colorado (the Durango site), the Surface Project cleanup occurred from 1986 to 1991. An evaluation was made to determine whether exposure to ground water contaminated by uranium processing could affect people`s health. Exposure could occur from drinking water pumped from a hypothetical well drilled in the contaminated ground water area. In addition, environmental risks may result if plants or animals are exposed to contaminated ground water, or surface water that has mixed with contaminated ground water. This risk assessment report is the first site-specific document prepared for the UMTRA Ground Water Project at the Durango site. The results of this report and further site characterization of the Durango site will be used to determine what is necessary to protect public health and the environment, and to comply with the EPA standards.

  12. Baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado

    SciTech Connect

    Not Available

    1994-11-01

    This baseline risk assessment of ground water contamination at the uranium mill tailings sites near Slick Rock, Colorado, evaluates potential public health and environmental impacts resulting from ground water contamination at the former North Continent (NC) and Union Carbide (UC) uranium mill processing sites. The tailings at these sites will be placed in a disposal cell at the proposed Burro Canyon, Colorado, site. The US Department of Energy (DOE) anticipates the start of the first phase remedial action by the spring of 1995 under the direction of the DOE`s Uranium Mill Tailings Remedial Action (UMTRA) Project. The second phase of the UMTRA Project will evaluate ground water contamination. This baseline risk assessment is the first site-specific document for these sites under the Ground Water Project. It will help determine the compliance strategy for contaminated ground water at the site. In addition, surface water and sediment are qualitatively evaluated in this report.

  13. Simulation of ground-water flow and evaluation of water-management alternatives in the Assabet River Basin, Eastern Massachusetts

    USGS Publications Warehouse

    DeSimone, Leslie A.

    2004-01-01

    Water-supply withdrawals and wastewater disposal in the Assabet River Basin in eastern Massachusetts alter the flow and water quality in the basin. Wastewater discharges and stream-flow depletion from ground-water withdrawals adversely affect water quality in the Assabet River, especially during low-flow months (late summer) and in headwater areas. Streamflow depletion also contributes to loss of aquatic habitat in tributaries to the river. In 19972001, water-supply withdrawals averaged 9.9 million gallons per day (Mgal/d). Wastewater discharges to the Assabet River averaged 11 Mgal/d and included about 5.4 Mgal/d that originated from sources outside of the basin. The effects of current (2004) and future withdrawals and discharges on water resources in the basin were investigated in this study. Steady-state and transient ground-water-flow models were developed, by using MODFLOW-2000, to simulate flow in the surficial glacial deposits and underlying crystalline bedrock in the basin. The transient model simulated the average annual cycle at dynamic equilibrium in monthly intervals. The models were calibrated to 19972001 conditions of water withdrawals, wastewater discharges, water levels, and nonstorm streamflow (base flow plus wastewater discharges). Total flow through the simulated hydrologic system averaged 195 Mgal/d annually. Recharge from precipitation and ground-water discharge to streams were the dominant inflow and outflow, respectively. Evapotranspiration of ground water from wetlands and non-wetland areas also were important losses from the hydrologic system. Water-supply withdrawals and infiltration to sewers averaged 5 and 1.3 percent, respectively, of total annual out-flows and were larger components (12 percent in September) of the hydrologic system during low-flow months. Water budgets for individual tributary and main stem subbasins identified areas, such as the Fort Meadow Brook and the Assabet Main Stem Upper subbasins, where flows resulting from

  14. An Online Interactive Map Service for Displaying Ground-Water Conditions in Arizona

    USGS Publications Warehouse

    Tillman, Fred D; Leake, Stanley A.; Flynn, Marilyn E.; Cordova, Jeffrey T.; Schonauer, Kurt T.

    2007-01-01

    Monitoring the availability of the nation's ground-water supplies is of critical importance to planners and water managers. The general public also has an interest in understanding the status of ground-water conditions, especially in the semi-arid Southwestern United States where much of the water used by municipalities and agriculture comes from the subsurface. Unlike surface-water indicators such as stage or discharge, ground-water conditions may be more difficult to assess and present. Individual well observations may only represent conditions in a limited area surrounding the well and wells may be screened over single or multiple aquifers, further complicating single-well measurement interpretations. Additionally, changes in ground-water conditions may involve time scales ranging from days to many years, depending on recharge, soil properties and depth to the water table. This lack of an easily identifiable ground-water property indicative of current conditions combined with differing time scales of water-level changes makes the presentation of ground-water conditions a difficult task, particularly on a regional basis. One approach is to spatially present several indicators of ground-water conditions that address different time scales and attributes of the aquifer systems. In this report, we describe a publicly-available online interactive map service that presents several different layers of ground-water-conditions information for the alluvial basins in the Lower Colorado River Basin in Arizona (http://montezuma.wr.usgs.gov/website/azgwconditions/). These data layers include wells experiencing water-level decline, wells experiencing water-level rise, recent trends in ground-water levels, change in water level since predevelopment and change in storage since predevelopment. Recent pumpage totals and projected population numbers are also provided for ground-water basins and counties in the region of the Lower Colorado River in Arizona along with a bibliography

  15. Hydrogeology and simulation of ground-water flow near the Lantana Landfill, Palm Beach County, Florida

    USGS Publications Warehouse

    Russell, G.M.; Wexler, E.J.

    1993-01-01

    The Lantana landfill in Palm Beach County has a surface that is 40 to 50 feet above original ground level and consists of about 250 acres of compacted garbage and trash. Parts of the landfill are below the water table. Surface-resistivity measurements and water-quality analyses indicate that leachate-enriched ground water along the eastern perimeter of the landfill has moved about 500 feet eastward toward an adjacent lake. Concentrations of chloride and nutrients within the leachate-enriched ground water were greater than background concentrations. The surficial aquifer system in the area of the landfill consists primarily of sand of moderate permeability, from land surface to a depth of about 68 feet deep, and consists of sand interbedded with sandstone and limestone of high permeability from a depth of about 68 feet to a depth of 200 feet. The potentiometric surface in the landfill is higher than that in adjacent areas to the east, indicating ground-water movement from the landfill toward a lake to the east. Steady-state simulation of ground-water flow was made using a telescoping-grid technique where a model covering a large area is used to determine boundaries and fluxes for a finer scale model. A regional flow model encompassing a 500-square mile area in southeastern Palm Beach County was used to calculate ground-water fluxes in a 126.5-square mile subregional area. Boundary fluxes calculated by the subregional model were then used to calculate boundary fluxes for a local model of the 3.75-square mile area representing the Lantana landfill site and vicinity. Input data required for simulating ground-water flow in the study area were obtained from the regional flow models, thus, effectively coupling the models. Additional simulations were made using the local flow model to predict effects of possible remedial actions on the movement of solutes in the ground-water system. Possible remedial actions simulated included capping the landfill with an impermeable layer

  16. Ground-water quality in selected areas of Wisconsin

    USGS Publications Warehouse

    Hindall, S.M.

    1979-01-01

    Analysis of 2,071 ground-water samples from 970 wells throughout Wisconsin indicate large variations in ground-water quality. Ground water in Wisconsin is generally suitable for most uses, but in some areas concentrations of chemical constituents exceed recommended drinking-water standards. Iron, manganese, and nitrate commonly exceed recommended drinking-water standards and dissolved solids, sulfate, heavy metals, and phenolic materials may present local problems. (USGS)

  17. Ground-water resources of Cambodia

    USGS Publications Warehouse

    Rasmussen, William Charles; Bradford, Gary M.

    1977-01-01

    available information is on the central lowlands and contiguous low plateaus, as the mountainous areas on the west and the high plateaus on the east are relatively unexplored with respect to their ground-water availability. No persistent artesian aquifer has been identified nor have any large potential ground-water sources been found .although much of the country yet remains to be explored by test drilling. Well irrigation for garden produce is feasible on a modest scale in many localities throughout Cambodia. It does not seem likely, however, that large-scale irrigation from wells will come about in the future. Ground water may be regarded as a widely available supplemental source to surface water for domestic, small-scale industrial, and irrigation use.

  18. Ground-water geology of Kordofan Province, Sudan

    USGS Publications Warehouse

    Rodis, Harry G.; Hassan, Abdulla; Wahadan, Lutfi

    1968-01-01

    For much of Kordofan Province, surface-water supplies collected and stored in hafirs, fulas, and tebeldi trees are almost completely appropriated for present needs, and water from wells must serve as the base for future economic and cultural development. This report describes the results of a reconnaissance hydrogeologic investigation of the Province and the nature and distribution of the ground-water resources with respect to their availability for development. Kordofan Province, in central Sudan, lies within the White Nile-Nile River drainage basin. The land surface is largely a plain of low relief; jebels (hills) occur sporadically, and sandy soils are common in most areas except in the south where clayey soils predominate. Seasonal rainfall, ranging from less than 100 millimeters in the north to about 800 millimeters in the south, occurs almost entirely during the summer months, but little runoff ever reaches the Nile or White Nile Rivers. The rocks beneath the surficial depsits (Pleistocene to Recent) in the Province comprise the basement complex (Precambrian), Nawa Series (upper Paleozoic), Nubian Series (Mesozoic), laterite (lower to middle Tertiary), and the Umm Ruwaba Series (Pliocene to Pleistocene). Perennial ground-water supplies in the Province are found chiefly in five hydrologic units, each having distinct geologic or hydrologic characteristics. These units occur in Nubian or Umm Ruwaba strata or both, and the sandstone and conglomerate beds form the :principal aquifers. The water is generally under slight artesian head, and the upper surface of the zone of saturation ranges from about 50 meters to 160 meters below land surface. The surficial deposits and basement rocks are generally poor sources of ground water in most of the Province. Supplies from such sources are commonly temporary and may dissipate entirely during the dry season. Locally, however, perennial supplies are obtained from the surficial deposits and from the basement rocks. Generally

  19. An overview of ground-water quality data in Wisconsin

    USGS Publications Warehouse

    Kammerer, Phil A.

    1984-01-01

    This report contains a summary of ground-water-quality data for Wisconsin and an evaluation of the adequacy of these data for assessing the impact of land disposal of wastes on ground-water quality. Chemical analyses used in data summaries were limited to those stored in the USGS computer system (WATSTORE). Information on documented instances of ground-water contamination and sources of potential contamination from land disposal of wastes was provided by the Wisconsin Department of Natural Resources. Available data provide an overview of ground water quality but may be insufficient for assessment of ground-water contamination from land disposal of wastes. Many sources of potential ground-water contamination (landfills, surface waste-storage impoundments, and buried tanks) are known. Some of these are probably causing local ground-water contamination that is not apparent from available regional data. Information needs for assessment of ground-water contamination from land disposal of wastes include improved understanding of both ground-water hydrology and the chemical behavior of specific contaminants in the environment. (USGS)

  20. Protecting ground water: pesticides and agricultural practices. Technical report (Final)

    SciTech Connect

    Not Available

    1988-02-01

    The booklet presents the results of a project conducted by EPA's Office of Ground-Water Protection to evaluate the potential impacts of various agronomic, irrigation, and pesticide application practices on ground water. The report provides State and local water quality and agricultural officials with technical information to help in the development of programs to protect ground water from pesticide contamination. The report explains the principles involved in reducing the risk of pesticide contamination and describes what is known about the impact of various agricultural practices on pesticide leaching. It is hoped that the information will be helpful to water-quality officials in developing and implementing ground-water protection programs.

  1. Hanford Site environmental data for calendar year 1990 -- Ground water

    SciTech Connect

    Dresel, P.E.; Bates, D.J.; Merz, J.K.

    1993-03-01

    This report tabulates ground-water radiological and chemical data for calendar year 1990 by the Ground-Water Surveillance Project, reported Resource Conservation and Recovery Act (RCRA) Monitoring, and Operational Monitoring. The Ground-Water Surveillance Project is conducted by the Pacific Northwest Laboratory and the RCRA and Operational Monitoring Projects are conducted by the Westinghouse Hanford Company. This document supplements the reports Hanford Site Ground-Water Monitoring for 1990 (Evans et al. 1992) and mental Report for Calendar Year 1990 (Woodruff and Hanf 1991). The data listings provided here were generated from the Hanford Environmental Information System database.

  2. Hanford Site environmental data for calendar year 1991 -- Ground water

    SciTech Connect

    Dresel, P.E.; Bates, D.J.; Merz, J.K.

    1993-03-01

    This report tabulates ground-water radiological and chemical data reported for calendar year 1991 by the Ground-Water Surveillance Project, Resource Conservation and Recovery Act (RCRA) Monitoring, and Operational Monitoring. The Ground-Water Surveillance Project is conducted by the Pacific Northwest Laboratory and the RCRA and Operational Monitoring Projects are conducted by the Westinghouse Hanford Company. This document supplements the reports Hanford Site Ground-Water Monitoring for 1991 (Evans et al. 1992) and Hanford Site Environmental Report for Calendar Year 1991 (Woodruff and Hanf 1992). The data listings provided here were generated from the Hanford Environmental Information System database.

  3. Ground-Water Availability in the United States

    USGS Publications Warehouse

    Reilly, Thomas E.; Dennehy, Kevin F.; Alley, William M.; Cunningham, William L.

    2008-01-01

    Ground water is among the Nation's most important natural resources. It provides half our drinking water and is essential to the vitality of agriculture and industry, as well as to the health of rivers, wetlands, and estuaries throughout the country. Large-scale development of ground-water resources with accompanying declines in ground-water levels and other effects of pumping has led to concerns about the future availability of ground water to meet domestic, agricultural, industrial, and environmental needs. The challenges in determining ground-water availability are many. This report examines what is known about the Nation's ground-water availability and outlines a program of study by the U.S. Geological Survey Ground-Water Resources Program to improve our understanding of ground-water availability in major aquifers across the Nation. The approach is designed to provide useful regional information for State and local agencies who manage ground-water resources, while providing the building blocks for a national assessment. The report is written for a wide audience interested or involved in the management, protection, and sustainable use of the Nation's water resources.

  4. The role of ground water in sub-Saharan Africa.

    PubMed

    Braune, Eberhard; Xu, Yongxin

    2010-01-01

    Although water resources managers speak of a water crisis in Africa, the management of ground water has to date not featured strongly in national and regional African water agendas. Examination of the physical environment of the continent and, in particular, the water resources in relation to the socioeconomic landscape and regional development challenges makes it clear that widely occurring, albeit largely low-yielding, ground water resources will be crucial in the achievement of water security and development. Ground water is important primarily in domestic water and sanitation services, but also for other local productive needs like community gardens, stock watering, and brick-making, all essential to secure a basic livelihood and thus to alleviate poverty. Despite the importance of small-scale farming in Africa, there is little information on the present and potential role of ground water in agriculture. In contrast to its socioeconomic and ecological importance, ground water has remained a poorly understood and managed resource. Widespread contamination of ground water resources is occurring, and the important environmental services of ground water are neglected. There appear to be critical shortcomings in the organizational framework and the building of institutional capacity for ground water. Addressing this challenge will require a much clearer understanding and articulation of ground water's role and contribution to national and regional development objectives and an integrated management framework, with top-down facilitation of local actions.

  5. Ground-water geology of the Gonaives Plain, Haiti

    USGS Publications Warehouse

    Taylor, George C.; Lemoine, Rémy C.

    1950-01-01

    marked by a water table. The depth to the water table beneath the alluvial lowland of the plain ranges from less than one meter to about 20 meters. In most places in the plain the depth to water is less that 15 meters. Where present in the zone of saturation the coarse, well-sorted sand and gravel beds of the alluvium will probably yield moderate to large supplies of water to wells and infiltration galleries. The individual yields of existing wells range from a few liters to about 60 liters per second. The most favorable part of the plain for ground-water prospecting and development lies 5 to 10 kilometers northeast of Gonaives. In this area yields of 10 to 50 liters per second could be obtained from the alluvium in simple wells drilled to depths of about 35 to 45 meters. Additional information on the yield and physical character of aquifers in the alluvium would be provided by test wells drilled to depths of 40 to 60 meters.

  6. Simulation of ground-water flow in the Prairie du Chien-Jordan and overlying aquifers near the Mississippi River, Fridley, Minnesota

    USGS Publications Warehouse

    Lindgren, R.J.

    1990-01-01

    Spatially variable leakage to the confined-drift and St. Peter aquifers in the steady-state simulation for 1885-1930 ranged from 1.0 to 2.3 inches per year. Leakage to the confined-drift and St. Peter aquifers in the steady-state simulation for 1970-79 increased 0 to 3.0 inches per year above the initial steady-state results. This increase represents additional leakage caused by the lowering of hydraulic heads due to ground-water withdrawals. Simulated leakage to the confined-drift and St. Peter aquifers for the transient simulation for 1987 varied both seasonally (0.4 to 2.1 inches per stress period) and spatially (2.6 to 5.7 inches per year). 

  7. Ground-water geology and pump irrigation in Frenchman Creek Basin above Palisade, Nebraska

    USGS Publications Warehouse

    Cardwell, W.D.E.; Jenkins, Edward D.

    1963-01-01

    quantities of water to wells. The ground-water reservoir is recharged only from precipitation on the basin. Of the average annual precipitation of 19.5 inches, about 0.9 inch infiltrates to the water table, thereby contributing about 220,000 acre-feet of water annually to the ground-water reservoir. About 81 million acre-feet of water that could drain under gravity, and thus theoretically is available to wells, is held in groundwater storage in the basin. Water is discharged from the ground-water reservoir by wells, evaporation and transpiration, springs, seepage into streams, and movement into adjacent areas to the east and southeast. Most of the domestic, stock, and irrigation water supplies and all the public supplies are pumped from wells. During 1953, 96 wells were used to irrigate 10,000 acres of land with 19,000 acre-feet of water. About 34,000 acre-feet of water is evaporated and transpired annually in the valleys of the main streams and in areas of shallow water table in the sandhills. From the projection of base-flow measurements made during 1952, it was estimated that the average annual flow of Frenchman Creek into the reservoir above Enders Dam is about 57,000 acre-feet. By similar determinations, the average annual flow of Frenchman Creek at the gaging station at Palisade, Nebr., about 22 miles downstream from Enders Dam, is about 76,000 acre-feet, and the flow of Stinking Water Creek at the gaging station near Palisade is about 22,000 acre-feet. The combined flow of Frenchman and Stinking Water Creeks at their confluence near Palisade thus is about 98,000 acre-feet per year. About 90,000 acre-feet of ground water is estimated to move eastward each year across the Colorado-Nebraska State line within the basin. Additional irrigation wells that will tap the Ogallala formation and the alluvium in the major valleys undoubtedly will be drilled. On the basis of current estimates of future irrigation.withdrawals, it is concluded that by the

  8. Availability of ground water in parts of the Acoma and Laguna Indian Reservations, New Mexico

    USGS Publications Warehouse

    Dinwiddie, George A.; Motts, Ward Sundt

    1964-01-01

    The need for additional water has increased in recent years on the Acoma and Laguna Indian Reservations in west-central New Mexico because the population and per capita use of water have increased; the tribes also desire water for light industry, for more modern schools, and to increase their irrigation program. Many wells have been drilled in the area, but most have been disappointing because of small yields and poor chemical quality of the water. The topography in the Acoma and Laguna Indian Reservations is controlled primarily by the regional and local dip of alternating beds of sandstone and shale and by the igneous complex of Mount Taylor. The entrenched alluvial valley along the Rio San Jose, which traverses the area, ranges in width from about 0.4 mile to about 2 miles. The climate is characterized by scant rainfall, which occurs mainly in summer, low relative humidity, and large daily fluctuations of temperature. Most of the surface water enters the area through the Rio San Jose. The average annual streamflow past the gaging station Rio San Jose near Grants, N. Mex. is about 4,000 acre-feet. Tributaries to the Rio San Jose within the area probably contribute about 1,000 acre-feet per year. At the present time, most of the surface water is used for irrigation. Ground water is obtained from consolidated sedimentary rocks that range in age from Triassic to Cretaceous, and from unconsolidated alluvium of Quaternary age. The principal aquifers are the Dakota Sandstone, the Tres Hermanos Sandstone Member of the Mancos Shale, and the alluvium. The Dakota Sandstone yields 5 to 50 gpm (gallons per minute) of water to domestic and stock wells. The Tres Hermanos sandstone Member generally yields 5 to 20 gpm of water to domestic and stock wells. Locally, beds of sandstone in the Chinle and Morrison Formations, the Entrada Sandstone, and the Bluff Sandstone also yield small supplies of water to domestic and stock wells. The alluvium yields from 2 gpm to as much as 150

  9. Denitrification in the shallow ground water of a tile-drained, agricultural watershed

    USGS Publications Warehouse

    Mehnert, E.; Hwang, H.-H.; Johnson, T.M.; Sanford, R.A.; Beaumont, W.C.; Holm, T.R.

    2007-01-01

    Nonpoint-source pollution of surface water by N is considered a major cause of hypoxia. Because Corn Belt watersheds have been identified as major sources of N in the Mississippi River basin, the fate and transport of N from midwestern agricultural watersheds have received considerable interest. The fate and transport of N in the shallow ground water of these watersheds still needs additional research. Our purpose was to estimate denitrification in the shallow ground water of a tile-drained, Corn Belt watershed with fine-grained soils. Over a 3-yr period, N was monitored in the surface and ground water of an agricultural watershed in central Illinois. A significant amount of N was transported past the tile drains and into shallow ground water. The ground water nitrate was isotopically heavier than tile drain nitrate, which can be explained by denitrification in the subsurface. Denitrifying bacteria were found at depths to 10 m throughout the watershed. Laboratory and push-pull tests showed that a significant fraction of nitrate could be denitrified rapidly. We estimated that the N denitrified in shallow ground water was equivalent to 0.3 to 6.4% of the applied N or 9 to 27% of N exported via surface water. These estimates varied by water year and peaked in a year of normal precipitation after 2 yr of below average precipitation. Three years of monitoring data indicate that shallow ground water in watersheds with fine-grained soils may be a significant N sink compared with N exported via surface water. ?? ASA, CSSA, SSSA.

  10. Denitrification in the shallow ground water of a tile-drained, agricultural watershed.

    PubMed

    Mehnert, Edward; Hwang, Hue-Hwa; Johnson, Thomas M; Sanford, Robert A; Beaumont, Will C; Holm, Thomas R

    2007-01-01

    Nonpoint-source pollution of surface water by N is considered a major cause of hypoxia. Because Corn Belt watersheds have been identified as major sources of N in the Mississippi River basin, the fate and transport of N from midwestern agricultural watersheds have received considerable interest. The fate and transport of N in the shallow ground water of these watersheds still needs additional research. Our purpose was to estimate denitrification in the shallow ground water of a tile-drained, Corn Belt watershed with fine-grained soils. Over a 3-yr period, N was monitored in the surface and ground water of an agricultural watershed in central Illinois. A significant amount of N was transported past the tile drains and into shallow ground water. The ground water nitrate was isotopically heavier than tile drain nitrate, which can be explained by denitrification in the subsurface. Denitrifying bacteria were found at depths to 10 m throughout the watershed. Laboratory and push-pull tests showed that a significant fraction of nitrate could be denitrified rapidly. We estimated that the N denitrified in shallow ground water was equivalent to 0.3 to 6.4% of the applied N or 9 to 27% of N exported via surface water. These estimates varied by water year and peaked in a year of normal precipitation after 2 yr of below average precipitation. Three years of monitoring data indicate that shallow ground water in watersheds with fine-grained soils may be a significant N sink compared with N exported via surface water.

  11. Delineating ground water recharge from leaking irrigation canals using water chemistry and isotopes.

    PubMed

    Harvey, F E; Sibray, S S

    2001-01-01

    Across the Great Plains irrigation canals are used to transport water to cropland. Many of these canals are unlined, and leakage from them has been the focus of an ongoing legal, economic, and philosophical debate as to whether this lost water should be considered waste or be viewed as a beneficial and reasonable use since it contributes to regional ground water recharge. While historically there has been much speculation about the impact of canal leakage on local ground water, actual data are scarce. This study was launched to investigate the impact of leakage from the Interstate Canal, in the western panhandle of Nebraska, on the hydrology and water quality of the local aquifer using water chemistry and environmental isotopes. Numerous monitoring wells were installed in and around a small wetland area adjacent to the canal, and ground water levels were monitored from June 1992 until January 1995. Using the water level data, the seepage loss from the canal was estimated. In addition, the canal, the monitoring wells, and several nearby stock and irrigation wells were sampled for inorganic and environmental isotope analysis to assess water quality changes, and to determine the extent of recharge resulting from canal leakage. The results of water level monitoring within study wells indicates a rise in local ground water levels occurs seasonally as a result of leakage during periods when the canal is filled. This rise redirects local ground water flow and provides water to nearby wetland ecosystems during the summer months. Chemical and isotopic results were used to delineate canal, surface, and ground water and indicate that leaking canal water recharges both the surface alluvial aquifer and upper portions of the underlying Brule Aquifer. The results of this study indicate that lining the Interstate Canal could lower ground water levels adjacent to the canal, and could adversely impact the local aquifer.

  12. Ground Water Redox Zonation near La Pine, Oregon: Relation to River Position within the Aquifer-Riparian Zone Continuum

    USGS Publications Warehouse

    Hinkle, Stephen R.; Morgan, David S.; Orzol, Leonard L.; Polette, Danial J.

    2007-01-01

    Increasing residential development since in the 1960s has lead to increases in nitrate concentrations in shallow ground water in parts of the 247 square mile study area near La Pine, Oregon. Denitrification is the dominant nitrate-removal process that occurs in suboxic ground water, and suboxic ground water serves as a barrier to transport of most nitrate in the aquifer. Oxic ground water, on the other hand, represents a potential pathway for nitrate transport from terrestrial recharge areas to the Deschutes and Little Deschutes Rivers. The effects of present and potential future discharge of ground-water nitrate into the nitrogen-limited Deschutes and Little Deschutes Rivers are not known. However, additions of nitrogen to nitrogen-limited rivers can lead to increases in primary productivity which, in turn, can increase the magnitudes of dissolved oxygen and pH swings in river water. An understanding of the distribution of oxic ground water in the near-river environment could facilitate understanding the vulnerability of these rivers and could be a useful tool for management of these rivers. In this study, transects of temporary wells were installed in sub-river sediments beneath the Deschutes and Little Deschutes Rivers near La Pine to characterize near-river reduction/oxidation (redox) conditions near the ends of ground-water flow paths. Samples from transects installed near the center of the riparian zone or flood plain were consistently suboxic. Where transects were near edges of riparian zones, most ground-water samples also were suboxic. Oxic ground water (other than hyporheic water) was uncommon, and was only detected near the outside edge of some meander bends. This pattern of occurrence likely reflects geochemical controls throughout the aquifer as well as geochemical processes in the microbiologically active riparian zone near the end of ground-water flow paths. Younger, typically less reduced ground water generally enters near-river environments through

  13. Ground-water resources of the Houston district, Texas

    USGS Publications Warehouse

    White, Walter N.; Rose, N.A.; Guyton, William F.

    1944-01-01

    This report covers the current phase of an investigation of the supply of ground water available for the Houston district and adjacent region, Texas,- that has been in progress during the past 10 years. The field operations included routine inventories of pumpage, measurements of water levels in observation wells and collection of other hydrologic data, pumping tests on 21 city-owned wells to determine coefficients of permeability and storage, and the drilling of 13 deep test wells in unexplored parts of the district. Considerable attention has been given to studies of the location of areas or beds of sand that contain salt water. The ground water occurs in beds of sand, sandstone, and gravel of Miocene, Pliocene, and Pleistocene age. These formations crop out in belts that dip southeastward from their outcrop areas and are encountered by wells at progressively greater depths toward the southeast. The beds throughout the section are lithologically similar, and there is little agreement among geologists as to their correlation. -In this investigation, however, the sediments, penetrated by the wells are separated into six zones, chiefly on the basis of electrical logs. Most of the water occurs in zone 3, which ranges in thickness from 800 to 1,200 feet. Large quantities of ground water are pumped in three areas in the Houston district, as follows: The Houston tromping area, which includes Houston and the areas immediately adjacent; the Pasadena pumping area, which includes the industrial section extending along the ship channel from the Houston city limits eastward to Deer Park; and the Katy pumping area, an irregular-shaped area of several hundred square miles, which is roughly centered around the town of Katy, 30 miles west of Houston. In 1930 the total combined withdrawal of ground water in the Houston and Pasadena pumping areas averaged about 50 million gallons a day. It declined somewhat during 1932 and 1933 and then gradually increased, until in 1935 the total

  14. Appraisal of ground water for irrigation in the Little Falls area, Morrison County, Minnesota

    USGS Publications Warehouse

    Helgesen, John O.

    1973-01-01

    Possible future response to pumping was studied through electric analog analyses by stressing the modeled aquifer system in accordance with areal variations in expected well yields. The model interpretation indicates most of the sustained pumpage would be obtained from intercepted base flow and evapotranspiration. Simulated withdrawals totaling 18,000 acre-feet of water per year for 10 years resulted in little adverse effect on the aquifer system. Simulated larger withdrawals, assumed to represent denser well spacing, caused greater depletion of aquifer storage, streamflow, and lake volumes, excessively so in some areas. Results of model analyses provide a guide for ground-water development by identifying the capability of all parts of the aquifer system to support sustained pumping for irrigation.

  15. Memorandum on ground-water investigations in the Sells area, Papago Indian Reservation, Pima County, Arizona

    USGS Publications Warehouse

    Coates, D.R.

    1954-01-01

    From 1950 to the present date the Ground Water Branch, U.S. Geological Survey, has been collecting data about the ground-water supply in the Sells area, at the request of the Bureau of Indian Affairs, Papago Indian Agency.  The purpose of these studies has been to aid in locating and developing additional ground-water supplies for the community of Sells, the agency headquarters.  The work has been financed by and has been in cooperation with the Papago Indian Agency.  In addition to the author of this memorandum, the following personnel aided in collecting data: D. G. Metzger, H. E. Skibitzke, S.F. Turner, H. N. Wolcott, and C. B. Yost, Jr.

  16. Ground water contamination from creosote sites

    SciTech Connect

    Kiilerich, O.; Arvin, E.

    1996-05-01

    Field data from 44 waste sites contaminated with creosote have been compiled in a database. The data from each site included geological and hydrogeological parameters and the concentrations of creosote compounds in the ground water at various distances from the pollution sources. The creosote compounds that were measured included mononuclear aromatic hydrocarbons and polynuclear aromatic hydrocarbons (PAH) and phenols. Already 50 m down-gradient of the creosote waste sites, 90% of the concentrations were from three to 50 times lower than at the source, and most of the median concentrations were below detection limit (0.1 to 0.5 {micro}g/L). The maximum concentrations of benzene, toluene, and xylenes (BTX) and phenols were much lower under aerobic than under anaerobic conditions. Among the phenols, the xylenols (dimethylphenols) appear in higher concentrations under aerobic conditions than phenol and the cresols do. The highest concentrations found were of the same order of magnitude as the calculated solubilities found in the literature, except the chrysene and benz(a)pyrene concentrations, which were one to two orders of magnitude higher than the solubilities.

  17. General database for ground water site information.

    PubMed

    de Dreuzy, Jean-Raynald; Bodin, Jacques; Le Grand, Hervé; Davy, Philippe; Boulanger, Damien; Battais, Annick; Bour, Olivier; Gouze, Philippe; Porel, Gilles

    2006-01-01

    In most cases, analysis and modeling of flow and transport dynamics in ground water systems require long-term, high-quality, and multisource data sets. This paper discusses the structure of a multisite database (the H+ database) developed within the scope of the ERO program (French Environmental Research Observatory, http://www.ore.fr). The database provides an interface between field experimentalists and modelers, which can be used on a daily basis. The database structure enables the storage of a large number of data and data types collected from a given site or multiple-site network. The database is well suited to the integration, backup, and retrieval of data for flow and transport modeling in heterogeneous aquifers. It relies on the definition of standards and uses a templated structure, such that any type of geolocalized data obtained from wells, hydrological stations, and meteorological stations can be handled. New types of platforms other than wells, hydrological stations, and meteorological stations, and new types of experiments and/or parameters could easily be added without modifying the database structure. Thus, we propose that the database structure could be used as a template for designing databases for complex sites. An example application is the H+ database, which gathers data collected from a network of hydrogeological sites associated with the French Environmental Research Observatory.

  18. GWM-a ground-water management process for the U.S. Geological Survey modular ground-water model (MODFLOW-2000)

    USGS Publications Warehouse

    Ahlfeld, David P.; Barlow, Paul M.; Mulligan, Anne E.

    2005-01-01

    GWM is a Ground?Water Management Process for the U.S. Geological Survey modular three?dimensional ground?water model, MODFLOW?2000. GWM uses a response?matrix approach to solve several types of linear, nonlinear, and mixed?binary linear ground?water management formulations. Each management formulation consists of a set of decision variables, an objective function, and a set of constraints. Three types of decision variables are supported by GWM: flow?rate decision variables, which are withdrawal or injection rates at well sites; external decision variables, which are sources or sinks of water that are external to the flow model and do not directly affect the state variables of the simulated ground?water system (heads, streamflows, and so forth); and binary variables, which have values of 0 or 1 and are used to define the status of flow?rate or external decision variables. Flow?rate decision variables can represent wells that extend over one or more model cells and be active during one or more model stress periods; external variables also can be active during one or more stress periods. A single objective function is supported by GWM, which can be specified to either minimize or maximize the weighted sum of the three types of decision variables. Four types of constraints can be specified in a GWM formulation: upper and lower bounds on the flow?rate and external decision variables; linear summations of the three types of decision variables; hydraulic?head based constraints, including drawdowns, head differences, and head gradients; and streamflow and streamflow?depletion constraints. The Response Matrix Solution (RMS) Package of GWM uses the Ground?Water Flow Process of MODFLOW to calculate the change in head at each constraint location that results from a perturbation of a flow?rate variable; these changes are used to calculate the response coefficients. For linear management formulations, the resulting matrix of response coefficients is then combined with other

  19. Geohydrology and ground-water resources of Philadelphia, Pennsylvania

    USGS Publications Warehouse

    Paulachok, Gary N.

    1991-01-01

    50 ft (feet) below sea level at the U.S. Naval Base and more than 70 ft below sea level along the Delaware River northeast of the naval base. As a result of withdrawals, declining heads in the lower sand unit caused water to flow downward from the overlying unconsolidated deposits and the water table to decline below sea level along the Delaware River. Beginning in the mid1960's, ground-water withdrawals from the lower sand unit decreased, and, by 1979, water levels had risen 25 ft at the U.S. Naval Base and 45 ft farther north along the Delaware River. As of 1985, water levels in the lower sand unit were controlled largely by pumping in nearby parts of New Jersey. Urbanization also has caused substantial degradation of the quality of ground water in Philadelphia. By 1945, the quality of water in the unconfined aquifer system began to deteriorate as contaminants present at the land surface migrated down- ward. Withdrawal of water from the deeper confined aquifers caused a head decline that resulted in downward movement of contaminated water from the overlying unconfined aquifer system. Consequently, water in the confined aquifers deteriorated progressively in chemical quality so it resembles water in the unconfined aquifer system. The concentration of dissolved solids in water samples collected during 1979-80 ranged from 90 to 4,480 mg/L (milligrams per liter). The average concentration of 778 mg/L was 45 percent higher than that of samples collected during 1945-58. Water from the unconfined unconsolidated aquifers generally had the highest dissolved-solids concentration. The concentration of dissolved iron in water samples collected during 197980 ranged from 0 to 220 mg/L and exceeded 0.30 mg/L in 71 percent of the samples. The average concentration of 17 mg/L was nearly 30 percent higher than that of samples collected during 1945-58. Many wells have been abandoned because of elevated iron concentrations. The concentration of dissolved manganese in water

  20. Water Use, Ground-Water Recharge and Availability, and Quality of Water in the Greenwich Area, Fairfield County, Connecticut and Westchester County, New York, 2000-2002

    USGS Publications Warehouse

    Mullaney, John R.

    2004-01-01

    Ground-water budgets were developed for 32 small basin-based zones in the Greenwich area of southwestern Connecticut, where crystalline-bedrock aquifers supply private wells, to determine the status of residential ground-water consumption relative to rates of ground-water recharge and discharge. Estimated residential ground-water withdrawals for small basins (averaging 1.7 square miles (mi2) ranged from 0 to 0.16 million gallons per day per square mile (Mgal/d/mi2). To develop these budgets, residential ground-water withdrawals were estimated using multiple-linear regression models that relate water use from public water supply to data on residential property characteristics. Average daily water use of households with public water supply ranged from 219 to 1,082 gallons per day (gal/d). A steady-state finite-difference ground-water-flow model was developed to track water budgets, and to estimate optimal values for hydraulic conductivity of the bedrock (0.05 feet per day) and recharge to the overlying till deposits (6.9 inches) using nonlinear regression. Estimated recharge rates to the small basins ranged from 3.6 to 7.5 inches per year (in/yr) and relate to the percentage of the basin underlain by coarse-grained glacial stratified deposits. Recharge was not applied to impervious areas to account for the effects of urbanization. Net residential ground-water consumption was estimated as ground-water withdrawals increased during the growing season, and ranged from 0 to 0.9 in/yr. Long-term average stream base flows simulated by the ground-water-flow model were compared to calculated values of average base flow and low flow to determine if base flow was substantially reduced in any of the basins studied. Three of the 32 basins studied had simulated base flows less than 3 in/yr, as a result of either ground-water withdrawals or reduced recharge due to urbanization. A water-availability criteria of the difference between the 30-day 2-year low flow and the recharge rate

  1. Documentation of the Santa Clara Valley regional ground-water/surface-water flow model, Santa Clara Valley, California

    USGS Publications Warehouse

    Hanson, R.T.; Li, Zhen; Faunt, C.C.

    2004-01-01

    The Santa Clara Valley is a long, narrow trough extending about 35 miles southeast from the southern end of San Francisco Bay where the regional alluvial-aquifer system has been a major source of water. Intensive agricultural and urban development throughout the 20th century and related ground-water development resulted in ground-water-level declines of more than 200 feet and land subsidence of as much as 12.7 feet between the early 1900s and the mid-1960s. Since the 1960s, Santa Clara Valley Water District has imported surface water to meet growing demands and reduce dependence on ground-water supplies. This importation of water has resulted in a sustained recovery of the ground-water flow system. To help support effective management of the ground-water resources, a regional ground-water/surface-water flow model was developed. This model simulates the flow of ground water and surface water, changes in ground-water storage, and related effects such as land subsidence. A numerical ground-water/surface-water flow model of the Santa Clara Valley subbasin of the Santa Clara Valley was developed as part of a cooperative investigation with the Santa Clara Valley Water District. The model better defines the geohydrologic framework of the regional flow system and better delineates the supply and demand components that affect the inflows to and outflows from the regional ground-water flow system. Development of the model includes revisions to the previous ground-water flow model that upgraded the temporal and spatial discretization, added source-specific inflows and outflows, simulated additional flow features such as land subsidence and multi-aquifer wellbore flow, and extended the period of simulation through September 1999. The transient-state model was calibrated to historical surface-water and ground-water data for the period 197099 and to historical subsidence for the period 198399. The regional ground-water flow system consists of multiple aquifers that are grouped

  2. Hydrology and quality of ground water in northern Thurston County, Washington

    USGS Publications Warehouse

    Dion, N.P.; Turney, G.L.; Jones, M.A.

    1994-01-01

    Northern Thurston County is underlain by as much as 1,000 feet of unconsolidated deposits of Pleistocene Age, that are of both glacial and nonglacial origin. Interpretation of 17 geelogic sections led to the delineation of 7 major geohydrologic units, 3 of which constitute aquifers in the area. Precipi- tation ranges from about 35 to 65 inches per year across the study area. Estimates of gross recharge from precipitation indicate that the ground-water system of the area receives about 25 inches per year. The net recharge to the system (recharge from precipitation minus withdrawals from wells) is the equivalent of about 23 inches per year. Ground water generally moves toward marine bodiesand to major surface drainage channels. Leakage from Lake St. Clair, which lies in a compound kettle within permeable glacial outwash, is almost 24 feet per year per unit area. Leakage from the lake may make up part of the water that discharges at McAllister Springs, north of the lake. Of the few water-quality problems encountered, the most widespread is seawater intrusion, which is caused by the activities of man. Most water-quality problems in the study area, however, are due to natural causes. Iron concentrations axe as large as 21,000 micrograms per liter, manganese concentrations are as large as 3,400 micrograms per liter, and connate seawater is present in ground water in the southern pan of the study area.

  3. Ground-water resources of coastal Citrus, Hernando, and southwestern Levy counties, Florida

    USGS Publications Warehouse

    Fretwell, J.D.

    1983-01-01

    Ground water in the coastal parts of Citrus, Hernando, and Levy Counties is obtained almost entirely from the Floridan aquifer. The aquifer is unconfined near the coast and semiconfined in the ridge area. Transmissivity ranges from 20,000 feet squared per day in the ridge area to greater than 2,000,000 feet squared per day near major springs. Changes in the potentiometric surface of the aquifer are small between the wet and dry seasons. Water quality within the study area is generally very good except immediately adjacent to the coast where saltwater from the Gulf of Mexico poses a threat to freshwater supply. This threat can be compensated for by placing well fields a sufficient distance away from the zone of transition from saltwater to freshwater so as not to reduce or reverse the hydraulic gradient in that zone. Computer models are presently available to help predict the extent of influence of ground-water withdrawals in an area. These may be used as management tools in planning ground-water development of the area. (USGS)

  4. Evaluation of the Effects of Precipitation on Ground-Water Levels from Wells in Selected Alluvial Aquifers in Utah and Arizona, 1936-2005

    USGS Publications Warehouse

    Gardner, Philip M.; Heilweil, Victor M.

    2009-01-01

    Increased withdrawals from alluvial aquifers of the southwestern United States during the last half-century have intensified the effects of drought on ground-water levels in valleys where withdrawal for irrigation is greatest. Furthermore, during wet periods, reduced withdrawals coupled with increased natural recharge cause rising ground-water levels. In order to manage water resources more effectively, analysis of ground-water levels under the influence of natural and anthropogenic stresses is useful. This report evaluates the effects of precipitation patterns on ground-water levels in areas of Utah and Arizona that have experienced different amounts of ground-water withdrawal. This includes a comparison of water-level records from basins that are hydrogeologically and climatologically similar but have contrasting levels of ground-water development. Hydrologic data, including records of ground-water levels, basin-wide annual ground-water withdrawals, and precipitation were examined from two basins in Utah (Milford and central Sevier) and three in Arizona (Aravaipa Canyon, Willcox, and Douglas). Most water-level records examined in this study from basins experiencing substantial ground-water development (Milford, Douglas, and Willcox) showed strong trends of declining water levels. Other water-level records, generally from the less-developed basins (central Sevier and Aravaipa Canyon) exhibited trends of increasing water levels. These trends are likely the result of accumulating infiltration of unconsumed irrigation water. Water-level records that had significant trends were detrended by subtraction of a low-order polynomial in an attempt to eliminate the variation in the water-level records that resulted from ground-water withdrawal or the application of water for irrigation. After detrending, water-level residuals were correlated with 2- to 10-year moving averages of annual precipitation from representative stations for the individual basins. The water

  5. Estimated ground-water availability in the Delaware River basin, 1997-2000

    USGS Publications Warehouse

    Sloto, Ronald A.; Buxton, Debra E.

    2006-01-01

    -gaging stations were selected to represent the 13 categories of predominant surficial geology and land use for the 38 Coastal Plain watersheds. A base-flow-recurrence analysis was used to determine the average annual 2-, 5-, 10-, 25-, and 50-year-recurrence intervals for each group of predominant surficial geology and land use. Average annual base flow for these watersheds ranged from 0.465 to 1.169 million gallons per day per square mile for the 2-year-recurrence interval to 0.178 to 0.670 million gallons per day per square mile for the 50-year-recurrence interval. Estimated 2-, 5-, 10-, 25-, and 50-year annual base-flow-recurrence interval values for each watershed in the Delaware River Basin are considered to be the quantity of ground water available for each watershed over a range of climatic conditions. The recurrence intervals are considered to be relative indicators of climatic difference; the 2-year-recurrence value represents wetter years, and the 50-year-recurrence value represents drier years. The remaining available ground water in each watershed was determined by subtracting current (1997-2000) ground-water withdrawals and consumptive domestic use and adding water recharged by agricultural irrigation and land application of treated-sewage effluent. Ground-water use ranged from 0 to 60.8 percent of available ground water for the 2-year-recurrence interval; it exceeded 25 percent in four watersheds and 50 percent in two watersheds. Ground-water use ranged from 0 to 75.9 percent of available ground water for the 5-year-recurrence interval; it exceeded 25 percent in five watersheds and 50 percent in three watersheds. Ground-water use ranged from 0 to 84.5 percent of available ground water for the 10-year-recurrence interval; it exceeded 25 percent in seven watersheds and 50 percent in four watersheds. Ground-water use ranged from 0 to 103 percent of available ground water for the 25-year-recurrence interval; it exceeded 25 percent in nine watersheds, 5

  6. Physical and chemical data for ground water in the Michigan basin, 1986-89

    USGS Publications Warehouse

    Dannemiller, G.T.; Baltusis, M.A.

    1990-01-01

    Ground-water samples were collected from 459 wells located in the Michigan basin as part of a Regional Aquifer-System Analysis. Data on the physical and chemical characteristics of 476 ground-water samples from these wells represent ground-water characteristics in the Berea Sandstone, Coldwater Shale, Marshall Sandstone, Michigan Formation, Bayport Limestone, Saginaw Formation, Grand River Formation, and glacial deposits. Ground-water samples were measured in the Geld for specific conductance, temperature, and alkalinity. Analyses of ground water for concentrations of dissolved oxygen, ferrous iron, total iron, and sulfide were also done in the field. Additional laboratory analysis provided data on eight major and 18 minor inorganic constituents. Twenty-one samples were analyzed for tritium, 140 samples were analyzed for carbon-13, and 19 samples were analyzed for carbon-14. The stable-isotope ratio of deuterium to hydrogen was determined for 408 samples; the ratio of oxygen-18 to oxygen-16 was determined for 433 samples; and the ratio of sulfur-34 to sulfur-32 was determined for 20 samples. Sixteen samples were analyzed for the unstable isotopes of uranium; 13 samples were analyzed for radium-226; and the ratio of radium-228 to radium-226 was determined for 13 samples.

  7. Quality of ground water in agricultural areas of the San Luis Valley, south-central Colorado

    USGS Publications Warehouse

    Edelmann, Patrick; Buckles, D.R.

    1984-01-01

    The quality of ground water in the principal agricultural areas of the San Luis Valley, south-central Colorado was evaluated using chemical analyses of water collected from 57 wells completed in the unconfined aquifer and from 25 wells completed in the confined aquifer. Ground water in both aquifers generally contains dissolved-solids concentrations of less than 500 milligrams per liter. In most areas, calcium is the principal cation in the ground water. Nitrite plus nitrate concentrations expressed as nitrogen, are generally less than 1 milligram per liter. However, the quality of ground water in certain areas may pose health and agricultural hazards. Water in the unconfined aquifer near Center contains high nitrite plus nitrate as nitrogen concentrations. The highest measured concentration in this area was 33 milligrams per liter. Water containing more than 1 milligram per liter of nitrite as nitrogen, or 10 milligrams per liter nitrate, as nitrogen, poses a potential health hazard for infants and should not be used for drinking. In addition, dissolved-solids concentration in the ground water in some areas is greater than 500 milligrams per liter and, if used for irrigation may reduce crop yields. (USGS)

  8. Estimated ground-water discharge by evapotranspiration, Ash Meadows Area, Nye County, Nevada, 1994

    SciTech Connect

    Nichols, W.D.; Laczniak, R.J.; DeMeo, G.A.; Rapp, T.R.

    1997-05-01

    Ground water discharges from the regional ground-water flow system that underlies the eastern part of the Nevada Test Site through numerous springs and seeps in the Ash Meadows National Wildlife Refuge in southern Nevada. The total spring discharge was estimated to be about 17,000 acre-feet per year by earlier studies. Previous studies estimated that about 10,500 acre-feet of this discharge was lost to evapotranspiration. The present study was undertaken to develop a more rigorous approach to estimating ground-water discharge in the Ash Meadows area. Part of the study involves detailed field investigation of evapotranspiration. Data collection began in early 1994. The results of the first year of study provide a basis for making preliminary estimates of ground-water discharge by evapotranspiration. An estimated 13,100 acre-feet of ground water was evapotranspired from about 6,800 acres of marsh and salt-grass. Additional 3,500 acre-feet may have been transpired from the open water and from about 1,460 acres of other areas of Ash Meadows in which field studies have not yet been made.

  9. (Environmental investigation of ground water contamination at Wright-Patterson Air Force Base, Ohio)

    SciTech Connect

    Not Available

    1991-10-01

    In April 1990 Wright-Patterson Air Force Base (WPAFB) initiated an investigation to evaluate a potential CERCLA removal action to prevent, to the extent practicable, the migration of ground-water contamination in the Mad River Valley Aquifer within and across WPAFB boundaries. The action will be based on a Focused Feasibility Study with an Action Memorandum serving as a decision document that is subject to approval by the Ohio Environmental Protection Agency. The first phase (Phase 1) of this effort involves an investigation of ground-water contamination migrating across the southwest boundary of Area C and across Springfield Pike adjacent to Area B. Task 4 of Phase 1 is a field investigation to collect sufficient additional information to evaluate removal alternatives. The field investigation will provide information in the following specific areas of study: water-level data which will be used to permit calibration of the ground-water flow model to a unique time in history; and ground-water quality data which will be used to characterize the current chemical conditions of ground water.

  10. Characterization and identification of Na-Cl sources in ground water

    USGS Publications Warehouse

    Panno, S.V.; Hackley, Keith C.; Hwang, H.-H.; Greenberg, S.E.; Krapac, I.G.; Landsberger, S.; O'Kelly, D. J.

    2006-01-01

    Elevated concentrations of sodium (Na+) and chloride (Cl -) in surface and ground water are common in the United States and other countries, and can serve as indicators of, or may constitute, a water quality problem. We have characterized the most prevalent natural and anthropogenic sources of Na+ and Cl- in ground water, primarily in Illinois, and explored techniques that could be used to identify their source. We considered seven potential sources that included agricultural chemicals, septic effluent, animal waste, municipal landfill leachate, sea water, basin brines, and road deicers. The halides Cl-, bromide (Br-), and iodide (I-) were useful indicators of the sources of Na+-Cl- contamination. Iodide enrichment (relative to Cl-) was greatest in precipitation, followed by uncontaminated soil water and ground water, and landfill leachate. The mass ratios of the halides among themselves, with total nitrogen (N), and with Na+ provided diagnostic methods for graphically distinguishing among sources of Na+ and Cl- in contaminated water. Cl/Br ratios relative to Cl- revealed a clear, although overlapping, separation of sample groups. Samples of landfill leachate and ground water known to be contaminated by leachate were enriched in I- and Br-; this provided an excellent fingerprint for identifying leachate contamination. In addition, total N, when plotted against Cl/Br ratios, successfully separated water contaminated by road salt from water contaminated by other sources. Copyright ?? 2005 National Ground Water Association.

  11. Environmental chemistry of ethylene dibromide in soil and ground water.

    PubMed

    Pignatello, J J; Cohen, S Z

    1990-01-01

    Ethylene dibromide is a ground water pollutant principally as a result of its use as a soil pesticide and secondarily from spills or leaks of leaded gasoline in which it is an additive. The compound has been found in over 1900 wells in 4 countries: Japan, Israel, Australia, and the United States (10 states), typically at concentrations of 0.04-4 micrograms/L. The overall rate of detections in suspected areas is about 13%. Its use as a soil fumigant was banned in the US in 1983 because of its carcinogenicity. Concern over gasoline as a source should diminish as leaded fuels all but disappear from the market in many countries. The voluminous research and regulatory attention devoted to EDB has generated a picture, if not an entirely clear one, of how EDB behaves in the environment and what we can expect for the future. EDB is volatile, moderately water soluble, and has only weak equilibrium sorptive affinity for soil. Transport to ground water occurs by both vapor-phase diffusion and by advection with infiltrating water, depending on soil properties and precipitation and irrigation patterns. Models describing these processes have been developed and validated in part by laboratory experiments, but the complexity and heterogeneity of the field makes predictions difficult there. As with other pesticides, experience indicates that areas with permeable soils and shallow water tables are most vulnerable. However, EDB seems to have penetrated many tens of meters of unsaturated zone in some cases to reach the water table. Transport in ground water occurs with bulk water flow, subject to hydrodynamic dispersion effects common to all solutes, and subject to sorptive retardation. From equilibrium sorption partition coefficients, plume migration is likely to be a factor of 2-4 slower than bulk water flow. Hydrolysis is the most important abiotic reaction. The reaction is independent of pH in the range 4-9 and is probably uncatalyzed by particle surfaces. Both SN1 and SN2

  12. Geology and occurrence of ground water in Lyon County, Minnesota

    USGS Publications Warehouse

    Rodis, Harry G.

    1963-01-01

    Large quantities of ground water are available from melt-water channels in the county. Moderate quantities, adequate for domestic and small industrial needs, are available from many of the small isolated deposits of sand and gravel in the till. Small quantities of ground water, adequate only for domestic supply, generally can be obtained from Cretaceous sandstone.

  13. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... to sewage sludge that is not used or disposed through a practice regulated in 40 CFR part 503 may... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an...

  14. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to sewage sludge that is not used or disposed through a practice regulated in 40 CFR part 503 may... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an...

  15. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... to sewage sludge that is not used or disposed through a practice regulated in 40 CFR part 503 may... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an...

  16. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... to sewage sludge that is not used or disposed through a practice regulated in 40 CFR part 503 may... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an...

  17. 40 CFR 257.3-4 - Ground water.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... to sewage sludge that is not used or disposed through a practice regulated in 40 CFR part 503 may... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Ground water. 257.3-4 Section 257.3-4... and Practices § 257.3-4 Ground water. (a) A facility or practice shall not contaminate an...

  18. Ground Water Quality Protection. State and Local Strategies.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Commission on Physical Sciences, Mathematics, and Resources.

    Using regional case studies, this document examines representative programs for dealing with ground water contamination. Section one describes the ground water protection strategy of the U.S. Environmental Protection Agency (EPA); (2) discusses the limited data available for determining the extent of contamination; (3) provides a listing of the…

  19. Ground-water resources of Rusk County, Texas

    USGS Publications Warehouse

    Sandeen, W.M.

    1984-01-01

    Some mineralization of ground water is due to natural causes. Other mineralization of ground water is due to contamination. A program needs to be initiated to determine the extent and cause of mineralization that has taken place in freshwater sands. Water-quality data is needed at Henderson in order to monitor saltwater encroachment.

  20. IN-SITU BIOREMEDIATION OF CONTAMINATED GROUND WATER

    EPA Science Inventory

    This document is one in a series of Ground Water Issue papers which have been prepared in response to needs expressed by the Ground Water Forum. It is based on findings from the research community in concert with experience gained at sites undergoing remediation. the intent of th...

  1. EPA Research Evaluating CAFO Impacts on Ground Water Quality

    EPA Science Inventory

    An overview of several projects will be presented on a research program currently underway at ORD’s Ground Water and Ecosystems Restoration Division (GWERD) to evaluate CAFO impacts on ground water quality. The overall research objectives are to characterize the potential for gro...

  2. Procedures for ground-water investigations. Revision 1

    SciTech Connect

    Not Available

    1992-12-01

    This manual was developed by the Pacific Northwest Laboratory (PNL) to document the procedures used to carry out and control the technical aspects of ground-water investigations at the PNL. Ground-water monitoring procedures are developed and used in accordance with the PNL Quality Assurance Program.

  3. Ground-water remediation with granular collection system

    SciTech Connect

    Frieseke, R.W.; Christensen, E.R.

    1996-06-01

    The purpose of this study is to evaluate the use of a granular ground-water collection system to increase ground-water recovery well yield and radial influence during remediation of gasoline-contaminated ground water. The field study was conducted at a site in Kenosha, Wisconsin. Two identical recovery wells were designed and installed within the granular ground-water collection system (RW No. 1) and the native silty fine sand soils (RW No. 2), respectively, in order to allow a direct comparison of recovery well yields and radial influence. The comparison was based on laboratory grain size and permeability tests, and in-situ yield and pump tests. The results show that RW No. 1 can produce 2.2--4.5 times the quantity of ground water of RW No. 2, and that the radial influence (ground-water drawdown) created by extracting from RW No. 1 was three to four times the drawdown from RW No. 2. There was a significant improvement in ground-water quality since the implementation of the remediation system. The achieved increase in the recovery well yield and radial influence should reduce the time and cost to complete a ground-water remediation project.

  4. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... aquifer (as defined in § 257.5(b)) that: (1) Represent the quality of background ground water that has not...-water contamination in the uppermost aquifer. The relevant point of compliance specified by the Director... uppermost aquifer. (b) The Director of an approved State may approve a multi-unit ground-water...

  5. 40 CFR 264.92 - Ground-water protection standard.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Releases From Solid Waste Management Units § 264.92 Ground-water protection standard. The owner or operator... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-water protection standard....

  6. Isotopes and sustainability of ground water resources, North China Plain.

    PubMed

    Zongyu, Chen; Zhenlong, Nie; Zhaoji, Zhang; Jixiang, Qi; Yunju, Nan

    2005-01-01

    Ground water in deep confined aquifers is one of the major water resources for agricultural, industrial, and domestic uses in the North China Plain. Detailed information on ground water age and recharge is vital for the proper management of these water resources, and to this end, we used carbon 14 of dissolved inorganic carbon and tritium in water to measure the age and determine the recharge areas of ground water in the North China Plain. These isotopic data suggest that most ground water in the piedmont part of the North China Plain is <40 years old and is recharged locally. In contrast, ground water in the central and littoral portions of the North China Plain is 10,000 to 25,000 years old. The delta18O (deltaD) values of this ground water are 1.7 per thousand (11 per thousand) less than that in the piedmont plain ground water and possibly reflect water recharged during a cooler climate during the last glaciation. The temperature of this recharge, based on delta18O values, ranges from 3.7 degrees C to 8.4 degrees C, compared to 12 degrees C to 13 degrees C of modern recharge water. The isotopic data set combined indicates that ground water in the central and littoral part of the North China Plain is being mined under non-steady state conditions.

  7. 40 CFR 257.22 - Ground-water monitoring systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... aquifer (as defined in § 257.5(b)) that: (1) Represent the quality of background ground water that has not been affected by leakage from a unit. A determination of background quality may include sampling of...) Sampling at other wells will provide an indication of background ground-water quality that is...

  8. Ground-water conditions in Whisky Flat, Mineral County, Nevada

    USGS Publications Warehouse

    Eakin, T.E.; Robinson, T.W.

    1950-01-01

    As a part of the State-wide cooperative program between the Office of the State Engineer of Nevada and the U.S. Geological Survey, the Ground Water Branch of the Geological Survey made a reconnaissance study of ground-water conditions in Whisky Flat, Mineral County, Nevada.

  9. Ground water hydrology report: Revision 1, Attachment 3. Final

    SciTech Connect

    1996-12-01

    This report presents ground water hydrogeologic activities for the Maybell, Colorado, Uranium Mill Tailings Remedial Action Project site. The Department of Energy has characterized the hydrogeology, water quality, and water resources at the site and determined that the proposed remedial action would comply with the requirements of the EPA ground water protection standards.

  10. Ground-water resources of the Clifton Park area, Saratoga County, New York

    USGS Publications Warehouse

    Heisig, Paul M.

    2002-01-01

    Ground water is the sole source of public water supply for Clifton Park, a growing suburban community north of Albany, New York. Increasing water demand, coupled with concerns over ground-water quantity and quality, led the Clifton Park Water Authority in 1995 to initiate a cooperative study with the U.S. Geological Survey to update and refine the understanding of ground-water resources in the area. Ground-water resources are largely associated with three aquifers in the eastern half of the area. These aquifers overlie or encompass the Colonie Channel, a north-south-oriented bedrock channel that is filled primarily with lacustrine glacial deposits. The three aquifers are: (1) an unconfined lacustrine sand aquifer, (2) the Colonie Channel aquifer, which is confined within the deepest parts of the channel and variably confined and unconfined within the shallower, peripheral channel areas, and (3) an unconfined alluvial aquifer beneath the Mohawk River flood plain, which represents the southern limit of the study area. The lacustrine sand aquifer has little potential for large-scale withdrawals because it is predominantly fine grained and is susceptible to contamination from human activities at land surface. Water from this aquifer can, however, recharge the underlying peripheral parts of the Colonie Channel aquifer where hydraulic connections are present. The Colonie Channel aquifer consists of thin sand and gravel and (or) shallow, fractured bedrock over much of the channel area; discontinuous deposits of thicker (more than 20 feet) sand and gravel are common in the peripheral channel areas. The deepest, or central, channel area of this aquifer is isolated from the overlying lacustrine sand aquifer by a continuous lacustrine silt and clay unit, which is the primary channel-fill deposit. The most productive areas of the Colonie Channel aquifer are typically the shallow peripheral areas, where conditions range from unconfined to confined. The most productive aquifer

  11. Silver(I) complexes of tris(pyrazolyl)borate ligands bearing six trifluoromethyl and three additional electron-withdrawing substituents.

    PubMed

    Jayaratna, Naleen B; Pardue, Daniel B; Ray, Sriparna; Yousufuddin, Muhammed; Thakur, Krishna G; Cundari, Thomas R; Dias, H V Rasika

    2013-11-21

    Sodium salts of two new tris(pyrazolyl)borates [HB(4-Cl-3,5-(CF3)2Pz)3](-) and [HB(4-(NO2)-3,5-(CF3)2Pz)3](-), which are not only highly fluorinated, but also loaded with additional electron-withdrawing substituents, have been synthesized by reacting 4-Cl-3,5-(CF3)2PzH or 4-(NO2)-3,5-(CF3)2PzH with NaBH4 under nitrogen in a solventless process, and isolated after a work up in tetrahydrofuran (THF) or diethyl ether (Et2O), as their THF or Et2O adducts. Metathesis of these sodium salts with AgOTf in THF leads to [HB(4-Cl-3,5-(CF3)2Pz)3]Ag(THF) and [HB(4-(NO2)-3,5-(CF3)2Pz)3]Ag(THF). The corresponding cis-cyclooctene (c-COE) complexes [HB(4-Cl-3,5-(CF3)2Pz)3]Ag(c-COE) and [HB(4-(NO2)-3,5-(CF3)2Pz)3]Ag(c-COE) were obtained by displacing THF with cis-cyclooctene. The related [HB(3,5-(CF3)2Pz)3]Ag(c-COE) can also be obtained via a similar process. X-ray crystal structures show that [HB(4-(R)-3,5-(CF3)2Pz)3]Ag(c-COE) (R = H, Cl, NO2) feature pseudo-tetrahedral silver sites supported by κ(3)-bound tris(pyrazolyl)borate ligands. [HB(4-(NO2)-3,5-(CF3)2Pz)3]Ag(c-COE) displays the smallest upfield shift of the alkene carbon peak (versus free alkene) followed by [HB(4-Cl-3,5-(CF3)2Pz)3]Ag(c-COE) and [HB(3,5-(CF3)2Pz)3]Ag(c-COE). Experimental and computational data indicate very electron poor silver(I) sites in all three [HB(4-(R)-3,5-(CF3)2Pz)3]Ag(c-COE) adducts with minimal Ag → (cis-cyclooctene) backbonding. Although the impact of R (H, Cl, NO2) on the alkene carbon chemical shift of these adducts and the olefin π/π* populations is small, the (13)C NMR chemical shifts and NBO analysis suggest that [HB(4-(NO2)-3,5-(CF3)2Pz)3]Ag(c-COE) possesses the most electrophilic metal site, which correlates with the pKa values of the free pyrazoles. [HB(4-(R)-3,5-(CF3)2Pz)3]Ag(c-COE) adducts effectively catalyze the insertion of the carbene moiety of ethyl diazoacetate into C-H bonds of 2,3-dimethylbutane. The [HB(4-(NO2)-3,5-(CF3)2Pz)3]Ag(c-COE) catalyst shows a higher selectivity

  12. Bioremediation of petroleum hydrocarbon-contaminated ground water: The perspectives of history and hydrology

    USGS Publications Warehouse

    Chapelle, F.H.

    1999-01-01

    Bioremediation, the use of microbial degradation processes to detoxify environmental contamination, was first applied to petroleum hydrocarbon-contaminated ground water systems in the early 1970s. Since that time, these technologies have evolved in some ways that were clearly anticipated early investigators, and in other ways that were not foreseen. The expectation that adding oxidants and nutrients to contaminated aquifers would enhance biodegradation, for example, has been born out subsequent experience. Many of the technologies now in common use such as air sparging, hydrogen peroxide addition, nitrate addition, and bioslurping, are conceptually similar to the first bioremediation systems put into operation. More unexpected, however, were the considerable technical problems associated with delivering oxidants and nutrients to heterogeneous ground water systems. Experience has shown that the success of engineered bioremediation systems depends largely on how effectively directions and rates of ground water flow can be controlled, and thus how efficiently oxidants and nutrients can be delivered to contaminated aquifer sediments. The early expectation that injecting laboratory-selected or genetically engineered cultures of hydrocarbon-degrading bacteria into aquifers would be a useful bioremediation technology has not been born out subsequent experience. Rather, it appears that petroleum hydrocarbon-degrading bacteria are ubiquitous in ground water systems and that bacterial addition is usually unnecessary. Perhaps the technology that was least anticipated early investigators was the development of intrinsic bioremediation. Experience has shown that natural attenuation mechanisms - biodegradation, dilution, and sorption - limit the migration of contaminants to some degree in all ground water systems. Intrinsic bioremediation is the deliberate use of natural attenuation processes to treat contaminated ground water to specified concentration levels at predetermined

  13. Evaluating data worth for ground-water management under uncertainty

    USGS Publications Warehouse

    Wagner, B.J.

    1999-01-01

    A decision framework is presented for assessing the value of ground-water sampling within the context of ground-water management under uncertainty. The framework couples two optimization models-a chance-constrained ground-water management model and an integer-programing sampling network design model-to identify optimal pumping and sampling strategies. The methodology consists of four steps: (1) The optimal ground-water management strategy for the present level of model uncertainty is determined using the chance-constrained management model; (2) for a specified data collection budget, the monitoring network design model identifies, prior to data collection, the sampling strategy that will minimize model uncertainty; (3) the optimal ground-water management strategy is recalculated on the basis of the projected model uncertainty after sampling; and (4) the worth of the monitoring strategy is assessed by comparing the value of the sample information-i.e., the projected reduction in management costs-with the cost of data collection. Steps 2-4 are repeated for a series of data collection budgets, producing a suite of management/monitoring alternatives, from which the best alternative can be selected. A hypothetical example demonstrates the methodology's ability to identify the ground-water sampling strategy with greatest net economic benefit for ground-water management.A decision framework is presented for assessing the value of ground-water sampling within the context of ground-water management under uncertainty. The framework couples two optimization models - a chance-constrained ground-water management model and an integer-programming sampling network design model - to identify optimal pumping and sampling strategies. The methodology consists of four steps: (1) The optimal ground-water management strategy for the present level of model uncertainty is determined using the chance-constrained management model; (2) for a specified data collection budget, the monitoring

  14. Ground-water resources of Riverton irrigation project area, Wyoming

    USGS Publications Warehouse

    Morris, Donald Arthur; Hackett, O.M.; Vanlier, K.E.; Moulder, E.A.; Durum, W.H.

    1959-01-01

    The Riverton irrigation project area is in the northwestern part of the Wind River basin in west-central Wyoming. Because the annual precipitation is only about 9 inches, agriculture, which is the principal occupation in the area, is dependent upon irrigation. Irrigation by surface-water diversion was begum is 1906; water is now supplied to 77,716 acres and irrigation has been proposed for an additional 31,344 acres. This study of the geology and ground-water resources of the Riverton irrigation project, of adjacent irrigated land, and of nearby land proposed for irrigation was begun during the summer of 1948 and was completed in 1951. The purpose of the investigation was to evaluate the ground-water resources of the area and to study the factors that should be considered in the solution of drainage and erosional problems within the area. The Riverton irrigation project area is characterized by flat to gently sloping stream terraces, which are flanked by a combination of badlands, pediment slopes, and broad valleys. These features were formed by long-continued erosion in an arid climate of the essentially horizontal, poorly consolidated beds of the Wind River formation. The principal streams of the area flow south-eastward. Wind River and Fivemile Creek are perennial streams and the others are intermittent. Ground-water discharge and irrigation return flow have created a major problem in erosion control along Fivemile Creek. Similar conditions might develop along Muddy and lower Cottonwood Creeks when land in their drainage basins is irrigated. The bedrock exposed in the area ranges in age from Late Cretaceous to early Tertiary (middle Eocene). The Wind River formation of early and middle Eocene age forms the uppermost bedrock formation in the greater part of the area. Unconsolidated deposits of Quaternary age, which consist of terrace gravel, colluvium, eolian sand and silt. and alluvium, mantle the Wind River formation in much of the area. In the irrigated parts

  15. Ground-water pollution by nitrogen compounds at Olean, New York; progress report, June 1977

    USGS Publications Warehouse

    Randall, Allan D.

    1978-01-01

    Ground water in an area in Olean, New York contains high concentrations of nitrogen compounds, which are being slowly flushed from the aquifer as the ground water flows toward a nearby well field where it is pumped out. Construction and regular use of a new production well in the area of nitrogen-rich water would temporarily increase the rate of nitrogen removal by causing more rapid flow of water from the silty upper part of the aquifer downward to the more permeable lower part, and by reducing the distance the water must flow through the lower part to the nearest point of withdrawal. After such a well had been in use for several months and the system had adjusted to the new conditions, the rate of further nitrogen removal would depend on the rate at which nitrogen compounds are leached from the soil by infiltrating precipitation. Alternative techniques for speeding the flushing of the aquifer include artificially increasing the amount of infiltration, changing the rates of withdrawal from existing production wells, and pumping shallow low-yield wells in the area of nitrogen-rich water. (Woodard-USGS)

  16. A geographic data model for representing ground water systems.

    PubMed

    Strassberg, Gil; Maidment, David R; Jones, Norm L

    2007-01-01

    The Arc Hydro ground water data model is a geographic data model for representing spatial and temporal ground water information within a geographic information system (GIS). The data model is a standardized representation of ground water systems within a spatial database that provides a public domain template for GIS users to store, document, and analyze commonly used spatial and temporal ground water data sets. This paper describes the data model framework, a simplified version of the complete ground water data model that includes two-dimensional and three-dimensional (3D) object classes for representing aquifers, wells, and borehole data, and the 3D geospatial context in which these data exist. The framework data model also includes tabular objects for representing temporal information such as water levels and water quality samples that are related with spatial features. PMID:17600583

  17. Pesticides in Ground Water - Sublette County, Wyoming, 2004-2005

    USGS Publications Warehouse

    Eddy-Miller, Cheryl A.; Remley, Kendra J.

    2006-01-01

    In 1991, members of local, State, and Federal governments, as well as industry and interest groups, formed the Ground-water and Pesticide Strategy Committee to prepare the State of Wyoming's generic Management Plan for Pesticides in Ground Water. Part of this management plan is to sample and analyze Wyoming's ground water for pesticides. In 1995, the U.S. Geological Survey, in cooperation with the Ground-water and Pesticide Strategy Committee, began statewide implementation of the sampling component of the State of Wyoming's generic Management Plan for Pesticides in Ground Water. During 2004-2005, baseline monitoring was conducted in Sublette County. This fact sheet describes and summarizes results of the baseline monitoring in Sublette County.

  18. Pesticides in Ground Water - Carbon County, Wyoming, 2004-2005

    USGS Publications Warehouse

    Eddy-Miller, Cheryl A.; Remley, Kendra J.

    2006-01-01

    In 1991, members of local, State, and Federal governments, as well as industry and interest groups, formed the Ground-water and Pesticide Strategy Committee to prepare the State of Wyoming's generic Management Plan for Pesticides in Ground Water. Part of this management plan is to sample and analyze Wyoming's ground water for pesticides. In 1995, the U.S. Geological Survey, in cooperation with the Ground-water and Pesticide Strategy Committee, began statewide implementation of the sampling component of the State of Wyoming's generic Management Plan for Pesticides in Ground Water. During 2004-2005, baseline monitoring was conducted in Carbon County. This fact sheet describes and summarizes results of the baseline monitoring in Carbon County.

  19. Pesticides in Ground Water - Campbell County, Wyoming, 2004-2005

    USGS Publications Warehouse

    Eddy-Miller, Cheryl A.; Remley, Kendra J.

    2006-01-01

    In 1991, members of local, State, and Federal governments, as well as industry and interest groups, formed the Ground-water and Pesticide Strategy Committee to prepare the State of Wyoming's generic Management Plan for Pesticides in Ground Water. Part of this management plan is to sample and analyze Wyoming's ground water for pesticides. In 1995, the U.S. Geological Survey, in cooperation with the Ground-water and Pesticide Strategy Committee, began statewide implementation of the sampling component of the State of Wyoming's generic Management Plan for Pesticides in Ground Water. During 2004-2005, baseline monitoring was conducted in Campbell County. This fact sheet describes and summarizes results of the baseline monitoring in Campbell County.

  20. Potential for satellite remote sensing of ground water.

    PubMed

    Becker, Matthew W

    2006-01-01

    Predicting hydrologic behavior at regional scales requires heterogeneous data that are often prohibitively expensive to acquire on the ground. As a result, satellite-based remote sensing has become a powerful tool for surface hydrology. Subsurface hydrology has yet to realize the benefits of remote sensing, even though surface expressions of ground water can be monitored from space. Remotely sensed indicators of ground water may provide important data where practical alternatives are not available. The potential for remote sensing of ground water is explored here in the context of active and planned satellite-based sensors. Satellite technology is reviewed with respect to its ability to measure ground water potential, storage, and fluxes. It is argued here that satellite data can be used if ancillary analysis is used to infer ground water behavior from surface expressions. Remotely sensed data are most useful where they are combined with numerical modeling, geographic information systems, and ground-based information.

  1. Modeling decadal timescale interactions between surface water and ground water in the central Everglades, Florida, USA

    USGS Publications Warehouse

    Harvey, J.W.; Newlin, J.T.; Krupa, S.L.

    2006-01-01

    Surface-water and ground-water flow are coupled in the central Everglades, although the remoteness of this system has hindered many previous attempts to quantify interactions between surface water and ground water. We modeled flow through a 43,000 ha basin in the central Everglades called Water Conservation Area 2A. The purpose of the model was to quantify recharge and discharge in the basin's vast interior areas. The presence and distribution of tritium in ground water was the principal constraint on the modeling, based on measurements in 25 research wells ranging in depth from 2 to 37 m. In addition to average characteristics of surface-water flow, the model parameters included depth of the layer of 'interactive' ground water that is actively exchanged with surface water, average residence time of interactive ground water, and the associated recharge and discharge fluxes across the wetland ground surface. Results indicated that only a relatively thin (8 m) layer of the 60 m deep surfical aquifer actively exchanges surface water and ground water on a decadal timescale. The calculated storage depth of interactive ground water was 3.1 m after adjustment for the porosity of peat and sandy limestone. Modeling of the tritium data yielded an average residence time of 90 years in interactive ground water, with associated recharge and discharge fluxes equal to 0.01 cm d -1. 3H/3He isotopic ratio measurements (which correct for effects of vertical mixing in the aquifer with deeper, tritium-dead water) were available from several wells, and these indicated an average residence time of 25 years, suggesting that residence time was overestimated using tritium measurements alone. Indeed, both residence time and storage depth would be expected to be overestimated due to vertical mixing. The estimate of recharge and discharge (0.01 cm d-1) that resulted from tritium modeling therefore is still considered reliable, because the ratio of residence time and storage depth (used to

  2. Geohydrology and simulation of ground-water flow near Los Alamos, north-central New Mexico

    USGS Publications Warehouse

    Frenzel, P.F.

    1995-01-01

    An existing model was modified in recognition of new geohydrologic interpretations and adjusted to simulate hydrographs in well fields in the Los Alamos area. Hydraulic-head drawdowns at the Buckman well field resulting from two projected ground-water-withdrawal alternatives were estimated with the modified model. The Chaquehui formation (informal usage) is the main new feature of recent hydrologic interpretations for the Los Alamos area. The Chaquehui occupies a 'channel' that was eroded or faulted into the Tesuque Formation, and the Chaquehui is more permeable than the Tesuque. The Chaquehui is a major producing zone in the Pajarito Mesa well field and to a lesser extent in the Guaje well field. Model modification included splitting the four layers of the McAda-Wasiolek model (McAda, D.P., and Wasiolek, Maryann, 1988, Simulation of the regional geohydrology of the Tesuque aquifer system near Santa Fe, New Mexico: U.S. Geological Survey Water- Resources Investigations Report 87-4056, 71 p.) into eight layers to better simulate vertical ground-water movement. Other model modifications were limited as much as possible to the area of interest near Los Alamos and consisted mainly of adjusting hydraulic-conductivity values representing the Tesuque Formation, Chaquehui formation (informal usage), and Puye Formation, and adjusting simulated recharge along the Pajarito Fault Zone west of Los Alamos. Adjustments were based mainly on simulation of fluctuations in measured hydraulic heads near Los Alamos. Two possible alternative plans for replacing Guaje well field production were suggested by Los Alamos National Laboratory. In the first plan (Guaje alternative), the Guaje field would be renewed with four new wells replacing the existing production wells in the Guaje field. In the second plan (Pajarito-Otowi alternative), the Guaje well field would be retired and its former production would be made up by additional withdrawals from the Pajarito Mesa and Otowi well fields. A

  3. Simulation of the effects of development of the ground-water flow system of Long Island, New York

    USGS Publications Warehouse

    Buxton, Herbert T.; Smolensky, Douglas A.

    1999-01-01

    Extensive development on Long Island since the late 19th century and projections of increased urbanization and ground-water use makes effective water-resource management essential for preservation of the island's hydrologic environment and maintenance of a reliable source of water supply. This report presents results of a ground-water flow simulation analysis of the effects of development on the Long Island ground-water system. It describes ground-water levels, stream-flow, and the ground-water budget for the predevelopment period (pre-1900), the 1960's drought, and a more recent (1968-83) period with significant hydrologic stress. The report also presents estimated effects of a proposed water-supply strategy for the year 2020. Long Island has three major aquifers-the upper glacial (water-table), the Magothy, and the Lloyd aquifers-that are separated to varying degrees by confining units. Before development, recharge from precipitation entered the ground-water system at a rate of more than 1.1 billion gallons per day. An equal amount discharged to streams (41 percent), the shore (52 percent), and subsea boundaries (7 percent) . Urbanization and withdrawal of more than 400 Mgal/d (million gallons per day) from wells have resulted in local effects that include declines in ground-water levels, drying up and burial of streams and wetlands, reduction of ground-water recharge by increased overland flow to the ocean, a general decrease in ground-water discharge, and salt water intrusion. In some areas, the reduction in recharge is mitigated by leakage from water-supply and wastewater disposal lines, and infiltration of storm water through recharge basins. During 1968-83, a net loss of 240 Mgal/d from the ground-water system caused a decrease in ground-water discharge to streams (135 Mgal/d), to the shore (82 Mgal/d), and to subsea boundaries (23Mgal/d).The greatest adverse effects have been in western Long Island, where the most severe development has occurred. This

  4. Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona--2003-04

    USGS Publications Warehouse

    Truini, Margot; Macy, Jamie P.; Porter, Thomas J.

    2005-01-01

    The N aquifer is the major source of water in the 5,400-square-mile area of Black Mesa in northeastern Arizona. Availability of water is an important issue in this area because of continued industrial and municipal use, a growing population, and precipitation of about 6 to 14 inches per year. The monitoring program in the Black Mesa area has been operating since 1971 and is designed to determine the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2003, total ground-water withdrawals were 7,240 acre-feet, industrial withdrawals were 4,450 acre-feet, and municipal withdrawals were 2,790 acre-feet. From 2002 to 2003, total withdrawals decreased by 10 percent, industrial withdrawals decreased by 4 percent, and municipal withdrawals decreased by 20 percent. Flowmeter testing was completed for 24 municipal wells in 2004. The median difference between pumping rates for the permanent meter and a test meter for all the sites tested was -2.9 percent. Values ranged from -10.9 percent at Forest Lake NTUA 1 to +7.8 percent at Rough Rock NTUA 2. From 2003 to 2004, water levels declined in 6 of 12 wells in the unconfined part of the aquifer, and the median change was -0.1 foot. Water levels declined in 7 of 11 wells in the confined part of the aquifer, and the median change was -2.7 feet. From the prestress period (prior to 1965) to 2003, the median water-level change for 26 wells was -23.2 feet. Median water-level change were -6.1 feet for 14 wells in the unconfined parts of the aquifer and and -72.1 feet for 12 wells in the confined part. Discharges were measured once in 2003 and once in 2004 at four springs. Discharge stayed the same at Pasture Canyon Spring, increased 9 percent at

  5. Ground-water, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona--2004-05

    USGS Publications Warehouse

    Truini, Margot; Macy, J.P.

    2006-01-01

    The N aquifer is the major source of water in the 5,400-square-mile area of Black Mesa in northeastern Arizona. Availability of water is an important issue in this area because of continued industrial and municipal use, a growing population, and precipitation of about 6 to 14 inches per year. The monitoring program in the Black Mesa area has been operating since 1971 and is designed to determine the long-term effects of ground-water withdrawals from the N aquifer for industrial and municipal uses. The monitoring program includes measurements of (1) ground-water pumping, (2) ground-water levels, (3) spring discharge, (4) surface-water discharge, (5) ground-water chemistry, and (6) periodic testing of ground-water withdrawal meters. In 2004, total ground-water withdrawals were 7,210 acre-feet, industrial withdrawals were 4,370 acre-feet, and municipal withdrawals were 2,840 acre-feet. From 2003 to 2004, total withdrawals decreased by less than 1 percent, industrial withdrawals decreased by 2 percent, and municipal withdrawals increased by 2 percent. From 2004 to 2005, annually measured water levels declined in 6 of 13 wells in the unconfined areas of the aquifer, and the median change was -0.1 foot. Water levels declined in 8 of 12 wells in the confined area of the aquifer, and the median change was -1.2 feet. From the prestress period (prior to 1965) to 2005, the median water-level change for 33 wells was -9.0 feet. Median water-level changes were -0.6 foot for 16 wells in the unconfined areas and -32.0 feet for 17 wells in the confined area. Discharges were measured once in 2004 and once in 2005 at four springs. Discharge increased by 8 percent at Pasture Canyon Spring, decreased by 5 percent at Moenkopi School Spring, increased by 71 percent at an unnamed spring near Dennehotso, and stayed the same at Burro Spring. For the period of record at each spring, discharges from the four springs have fluctuated; however, an increasing or decreasing trend is not apparent

  6. Generalized estimates from streamflow data of annual and seasonal ground-water-recharge rates for drainage basins in New Hampshire

    USGS Publications Warehouse

    Flynn, Robert H.; Tasker, Gary D.

    2004-01-01

    This report presents regression equations to estimate generalized annual and seasonal ground-water-recharge rates in drainage basins in New Hampshire. The ultimate source of water for a ground-water withdrawal is aquifer recharge from a combination of precipitation on the aquifer, ground-water flow from upland basin areas, and infiltration from streambeds to the aquifer. An assessment of ground-water availability in a basin requires that recharge rates be estimated under `normal' conditions and under assumed drought conditions. Recharge equations were developed by analyzing streamflow, basin characteristics, and precipitation at 55 unregulated continuous record stream-gaging stations in New Hampshire and in adjacent states. In the initial step, streamflow records were analyzed to estimate a series of annual and seasonal ground-water-recharge components of streamflow in each drainage basin evaluated in this study. Regression equations were then developed relating the series of annual and seasonal ground-water-recharge values to the corresponding series of annual and seasonal precipitation values as determined at the centroid of each drainage basin. This resulted in one equation for each of the 55 basins for each of the four seasonal periods and the annual period, or a total of 275 regression equations. Average annual and seasonal precipitation data for 1961-90 were then used to compute a set of normalized ground-water-recharge values that reflected the long-term average annual and seasonal variations (normalized) and mean recharge characteristics of each drainage basin. Ordinary-least-squares regression was applied in the process of selecting 10 out of 93 possible basin and climatic characteristics for further testing in the development of the equations for computing the generalized estimate of annual and seasonal ground-water recharge based on the set of normalized recharge values. Generalized-least-squares regression was used for the final parameter estimation and

  7. Ground water in the Blanchard area, McClain County, Oklahoma

    USGS Publications Warehouse

    Davis, Leon Virgil; Schoff, Stuart L.

    1948-01-01

    A letter from Lloyd L. Bowser, City Clerk, dated January 8, 1948, in behalf of the town council and Mayor Walter Casey, indicates that a serious shortage of water is faced by the town of Blanchard, McClain County, Oklahoma. The town is near the eastern boundary of Grady County, where an investigation of the ground-water resources is being made by the Oklahoma Geological Survey in cooperation with the U.S. Geological Survey as part of a State-wide investigation. Information obtained thus far may aid the town by showing where additional ground water for municipal supply may be sought.

  8. Well-construction, water-level, and water-quality data for ground-water monitoring wells for the J4 hydrogeologic study, Arnold Air Force Base, Tennessee

    USGS Publications Warehouse

    Haugh, C.J.

    1996-01-01

    Between December 1993 and March 1994, 27 wells were installed at 12 sites near the J4 test cell at Arnold Engineering Development Center in Coffee County, Tennessee. The wells ranged from 28 to 289 feet deep and were installed to provide information on subsurface lithology, aquifer characteristics, ground-water levels, and ground-water quality. This information will be used to help understand the effects of dewatering operations at the J4 test cell on the local ground-water-flow system. The J4 test cell, extending approximately 250 feet below land surface, is used in the testing of rocket motors. Ground water must be pumped continuously from around the test cell to keep it structurally intact. The amount of water discharged from the J4 test cell was monitored to estimate the average rate of ground-water withdrawal at the J4 test cell. Ground- water levels were monitored continuously at 14 wells for 12 months. Water-quality samples were collected from 26 of the new wells, 9 existing wells, and the ground-water discharge from the J4 test cell. All samples were analyzed for common inorganic ions, trace metals, and volatile organic compounds.

  9. Chloride Concentrations in Ground Water in East and West Baton Rouge Parishes, Louisiana, 2004-05

    USGS Publications Warehouse

    Lovelace, John K.

    2007-01-01

    Increasing chloride concentrations are a threat to fresh ground-water sources in East Baton Rouge and West Baton Rouge Parishes, Louisiana. Large withdrawals at Baton Rouge have lowered water levels and altered flow patterns in most of the 10 aquifers that underlie the area. Prior to development, freshwater flowed southward to the Baton Rouge fault, an east-west trending growth fault that extends through Baton Rouge and across southeastern Louisiana. Aquifers south of the fault generally contain saltwater. Ground-water withdrawals north of the fault have created gradients favorable for the movement of saltwater from south of the fault into freshwater areas north of the fault. Water samples were collected from 152 wells during 2004-05 to document chloride concentrations in aquifers underlying East and West Baton Rouge Parishes. The background concentration for chloride in fresh ground water in the Baton Rouge area north of the Baton Rouge fault is generally less than 10 milligrams per liter. Chloride concentrations exceeded 10 milligrams per liter in one or more samples from wells north of the fault screened in the '600-foot', '1,000-foot', '1,200-foot', '1,500-foot', '1,700-foot', '2,000-foot', '2,400-foot', and '2,800-foot' sands. Comparison of the 2004-05 data with historical data indicated that chloride concentrations are increasing at wells in the '600-foot', '1,000-foot', '1,200-foot', '1,500-foot', '2,000-foot', '2,400-foot', and '2,800-foot' sands north of the Baton Rouge fault.

  10. Numerical Simulation of Regional Changes in Ground-Water Levels and in the Freshwater-Saltwater Interface Induced by Increased Pumpage at Barbers Point Shaft, Oahu, Hawaii

    USGS Publications Warehouse

    Souza, William R.; Meyer, William

    1995-01-01

    The effect on the regional ground-water system of southern Oahu from increased pumpage at Barbers Point shaft was estimated by a numerical ground-water model developed for the Oahu Regional Aquifer Systems Analysis (RASA) study. The RASA model was updated by revising pumping and ground-water recharge data. Pumpage data used in the new simulations were based on the allocated pumping rates for 1995 as set by the State Commission on Water Resource Management. On the basis of numerical simulation, Barbers Point shaft can sustain a withdrawal rate of 4.34 million gallons per day without adversely affecting wells in the Waianae aquifer. From results of numerical simulations, it is estimated that, as a result of increasing pumpage in Barbers Point shaft by 2 million gallons per day above the 1995-allocated rate of 2.337 million gallons per day, regional declines in ground-water levels will be about 0.4 to 0.7 feet throughout the Waianae aquifer and about 0.8 ft at the shaft. The corresponding rise of the freshwater-saltwater interface, as a result of declines in ground-water levels, is estimated to be about 20 to 30 feet. Numerical simulation also indicates that changes in ground-water levels greater than about 0.1 feet do not extend across either the Waianae-Koolau unconformity or the south Schofield barrier. The model-estimated position of the freshwater-saltwater interface, as a result of additional pumpage, ranges from 500 to 860 feet below sea level in the southern and northern parts of the aquifer, respectively, and about 540 feet below sea level at the shaft. On the basis of an estimate of the thickness of the transition-zone, the freshwater lens would remain about 240 feet thick below the shaft. In addition, the estimated declines in ground-water levels throughout the aquifer are small compared with the thickness of the freshwater lens and these declines would not be expected to affect the yields of other wells in terms of quantity. Chloride concentrations in the

  11. Development of a three-dimensional ground-water model of the Hanford Site unconfined aquifer system: FY 1995 status report

    SciTech Connect

    Wurstner, S.K.; Thorne, P.D.; Chamness, M.A.; Freshley, M.D.; Williams, M.D.

    1995-12-01

    A three-dimensional numerical model of ground-water flow was developed for the uppermost unconfined aquifer at the Hanford Site in south-central Washington. Development of the model is supported by the Hanford Site Ground-Water Surveillance Project, managed by the Pacific Northwest National Laboratory, which is responsible for monitoring the sitewide movement of contaminants in ground water beneath the Hanford Site. Two objectives of the Ground-Water Surveillance Project are to (1) identify and quantify existing, emerging, or potential ground-water quality problems, and (2) assess the potential for contaminants to migrate from the Hanford Site through the ground-water pathway. Numerical models of the ground-water flow system are important tools for estimating future aquifer conditions and predicting the movement of contaminants through ground water. The Ground-Water Surveillance Project has supported development and maintenance of a two-dimensional model of the unconfined aquifer. This report describes upgrade of the two-dimensional model to a three-dimensional model. The numerical model is based on a three-dimensional conceptual model that will be continually refined and updated as additional information becomes available. This report presents a description of the three-dimensional conceptual model of ground-water flow in the unconfined aquifer system and then discusses the cur-rent state of the three-dimensional numerical model.

  12. Water-level predictions for Indian Wells Valley ground-water basin, California, 1978

    USGS Publications Warehouse

    Mallory, Michael J.

    1979-01-01

    Ground-water pumpage in Indian Wells Valley, virtually a closed basin in the Mojave Desert of southern California, has increased gradually since 1945 and presently exceeds the long-term mean annual recharge (perennial supply). In order to aid in the understanding and management of the ground-water basin, a digital ground-water model was constructed by the U.S. Geological Survey. Since the original development of this model, conditions in the basin, including areal distribution and rates of ground-water pumpage, have changed. The results of simulation for the period 1969-76 constitute a second verification of the original model. Calculated heads for 1976 agree with the observed heads, indicating a good calibration of the original model. A predictive simulation for the period 1977-2020 used pumpage values increasing from about 15,500 acre-feet per year to about 26,000 acre-feet per year. The pumpage used in this report reflects a slightly slower growth rate and a more concentrated pattern of development than that investigated when the model was originally developed. The effects of this pattern of pumpage are reflected in the water levels simulated by the model. Predicted drawdowns for 1983 are less extensive but locally more severe than those predicted earlier. The reversal of the hydraulic gradient between China Lake playa and the city of Ridgecrest, as produced by these drawdowns by the year 2020, suggests that the water-quality effects of such drawdowns should be investigated, as this could result in inferior water from the China Lake playa area flowing southward into areas of withdrawal. (Woodard-USGS)

  13. Effects of changing irrigation practices on the ground-water hydrology of the Santa Isabel-Juana Diaz area, south central Puerto Rico

    USGS Publications Warehouse

    Ramos-Gines, Orlando

    1994-01-01

    Prior to 1930, the principal source of water for irrigation in the Santa Isabel-Juana Diaz area was surface water from outside the study area, which was delivered by a complex channel-pond system. Recharge from water applied to the fields, estimated to be 18.7 million of gallons per day, and discharge by ground-water flow to sea, estimated to be 17 million of gallons per day, were the major water- budget components prior to intensive development of the ground-water resources. Development of the ground-water resources after 1930 resulted in a substantial increase in irrigation, primarily furrow irrigation. The surface water supplied by the complex channel-pond system continued to be used and ground-water withdrawals increased sub- stantially. By 1966-68, ground-water recharge from irrigation water applied to the fields, estimated to be 37 million of gallons per day, and discharge by pumpage for irrigation, estimated to be 77 million of gallons per day, were the two major components of the ground-water budget. By 1987, drip irrigation had become the principal method of irrigation in the study area, and surface-water irrigation had, for the most part, been discontinued. The estimated aquifer recharge from irrigation water in 1987 was about 6.6 million of gallons per day, which occurred primarily in the remaining fields where furrow irrigation was still practiced. Although aquifer recharge had been reduced as a result of the conversion from furrow to drip irrigation, water levels in the aquifer were higher in 1987 than in 1968 because of the large reduction in ground-water withdrawals and subsequent recovery of ground-water levels.

  14. Ground-water modeling of pumping effects near regional ground-water divides and river/aquifer systems - Results and implications of numerical experiments

    USGS Publications Warehouse

    Sheets, Rodney A.; Dumouchelle, Denise H.; Feinstein, Daniel T.

    2005-01-01

    Agreements between United States governors and Canadian territorial premiers establish water-management principles and a framework for protecting Great Lakes waters, including ground water, from diversion and consumptive uses. The issue of ground-water diversions out of the Great Lakes Basin by large-scale pumping near the divides has been raised. Two scenario models, in which regional ground-water flow models represent major aquifers in the Great Lakes region, were used to assess the effect of pumping near ground-water divides. The regional carbonate aquifer model was a generalized model representing northwestern Ohio and northeastern Indiana; the regional sandstone aquifer model used an existing calibrated ground-water flow model for southeastern Wisconsin. Various well locations and pumping rates were examined. Although the two models have different frameworks and boundary conditions, results of the models were similar. There was significant diversion of ground water across ground-water divides due to pumping within 10 miles of the divides. In the regional carbonate aquifer model, the percentage of pumped water crossing the divide ranges from about 20 percent for a well 10 miles from the divide to about 50 percent for a well adjacent to the divide. In the regional sandstone aquifer model, the percentages range from about 30 percent for a well 10 miles from the divide to about 50 percent for a well adjacent to the divide; when pumping on the west side of the divide, within 5 mi of the predevelopment divide, results in at least 10 percent of the water being diverted from the east side of the divide. Two additional scenario models were done to examine the effects of pumping near rivers. Transient models were used to simulate a rapid stage rise in a river during pumping at a well in carbonate and glacial aquifers near the river. Results of water-budget analyses indicate that induced infiltration, captured streamflow, and underflow were important for both glacial and

  15. Numerical Analysis of Ground-Water Flow and Salinity in the Ewa Area, Oahu, Hawaii

    USGS Publications Warehouse

    Oki, Delwyn S.; Souza, William R.; Bolke, Edward I.; Bauer, Glenn R.

    1996-01-01

    The coastal plain in the Ewa area of southwestern Oahu, Hawaii, is part of a larger, nearly continuous sedimentary coastal plain along Oahu's southern coast. The coastal sediments are collectively known as caprock because they impede the free discharge of ground water from the underlying volcanic aquifers. The caprock is a layered sedimentary system consisting of interbedded marine and terrestrial sediments of both high and low permeability. Before sugarcane cultivation ended in late 1994, shallow ground water from the upper limestone unit, which is about 60 to 200 feet thick, was used primarily for irrigation of sugarcane. A cross-sectional ground-water flow and transport model was used to evaluate the hydrogeologic controls on the regional flow system in the Ewa area. Controls considered were: (1) overall caprock hydraulic conductivity, (2) stratigraphic variations of hydraulic conductivity in the caprock, and (3) recharge. In addition, the effects of a marina excavation were evaluated. Within the caprock, variations in hydraulic conductivity, caused by caprock stratigraphy or discontinuities of the stratigraphic units, are a major control on the direction of ground-water flow and the distribution of water levels and salinity. Model results also show that a reduction of recharge will result in increased salinity throughout the caprock with the greatest change in the upper limestone layer. In addition, the model indicates that excavation of an ocean marina will lower water levels in the upper limestone layer. Results of cross-sectional modeling confirm the general ground-water flow pattern that would be expected in the layered sedimentary system in the Ewa caprock. Ground-water flow is: (1) predominantly upward in the low-permeability sedimentary units, and (2) predominantly horizontal in the high-permeability sedimentary units.

  16. 40 CFR 144.87 - How does the identification of ground water protection areas and other sensitive ground water...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false How does the identification of ground water protection areas and other sensitive ground water areas affect me? 144.87 Section 144.87 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS (CONTINUED) UNDERGROUND INJECTION CONTROL PROGRAM Requirements...

  17. The importance of ground water in the Great Lakes Region

    USGS Publications Warehouse

    Grannemann, N.G.; Hunt, R.J.; Nicholas, J.R.; Reilly, T.E.; Winter, T.C.

    2000-01-01

    Ground water is a major natural resource in the Great Lakes Region that helps link the Great Lakes and their watershed. This linkage needs to be more fully understood and quantified before society can address some of the important water-resources issues in the Great Lakes. The Great Lakes constitute the largest concentration of unfrozen fresh surface water in the western hemisphere—about 5,440 mi3. Because the quantity of water in the lakes is so large, ground water in the Great Lakes Basin is often overlooked when evaluating the hydrology of the region. Ground water, however, is more important to the hydrology of the Great Lakes and to the health of ecosystems in the watershed than is generally recognized.Although more than 1,000 mi3 of ground water are stored in the basin—a volume of water that is approximately equal to that of Lake Michigan—development of the groundwater resource must be carefully planned. Development of the ground-water resource removes water from storage and alters the paths of ground-water flow. Ground water that normally discharges to streams, lakes, and wetlands can be captured by pumping (the most common form of development), which may deplete or reduce inflows to the Great Lakes.Ground water is important to ecosystems in the Great Lakes Region because it is, in effect, a large, subsurface reservoir from which water is released slowly to provide a reliable minimum level of water flow to streams, lakes, and wetlands. Ground-water discharge to streams generally provides good quality water that, in turn, promotes habitat for aquatic animals and sustains aquatic plants during periods of low precipitation. Because of the slow movement of ground water, the effects of surface activities on ground-water flow and quality can take years to manifest themselves. As a result, issues relative to ground water are often seemingly less dire than issues related to surface water alone.Ground water is a major natural resource in the Great Lakes Region

  18. Pesticides in ground water: distribution, trends, and governing factors

    USGS Publications Warehouse

    Barbash, Jack; Resek, Elizabeth A.

    1997-01-01

    A comprehensive review of published information on the distribution and behavior of pesticides and their transformation products in ground water indicates that pesticides from every chemical class have been detected in ground waters of the United States. Many of these compounds are commonly present at low concentrations in ground water beneath agricultural land. Little information is available on their occurrence beneath non-agricultural land, although the intensity of their use in such areas (on lawns, golf courses, rights of way, timberlands, etc.) is often comparable to, or greater than agricultural use. Information on pesticides in ground water is not sufficient to provide either a statistically representative view of pesticide occurrence in ground water across the United States, or an indication of long-term trends or changes in the severity or extent of this contamination over the past three decades. This is largely due to wide variations in analytical detection limits, well selection procedures, and other design features among studies conducted in different areas or at different times. Past approaches have not been well suited for distinguishing "point source" from "nonpoint source" pesticide contamination. Among the variety of natural and anthropogenic factors examined, those t