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Hydrologic data for 1994-96 for the Huron Project of the High Plains Ground-Water Demonstration Program

This report presents data on precipitation, water levels, and water quality that have been collected or compiled for water years 1994 through 1996 for the Huron Project of the High Plains Ground-Water Demonstration Program, under the guidance of the Bureau of Reclamation. This is the second report for the project. The first report (Carter, 1995) presented data collected through water year 1993. The purpose of the Huron Project is to demonstrate the artificial recharge potential of glacial aquifers in eastern South Dakota. High flows from the James River during spring runoff were used as a source of supplemental recharge for the Warren aquifer, which is a buried, glacial aquifer. In 1990, 70 observation wells were installed by the South Dakota Department of Environment and Natural Resources (DENR) specifically for this study, and 15 existing DENR observation wells were incorporated into the study. In 1993, the recharge well was installed. After a trial injection of recharge water in April 1994, continuous injection began in June 1994. Many sites were monitored to obtain information before, during, and after recharging the aquifer. This report presents data that were collected during the three phases of recharge. Precipitation data are collected at two sites within the study area. A site description and daily precipitation for water years 1994-95 are presented for one precipitation site. Water-level hydrographs are presented for the 85 observation wells and the recharge well. Hydrographs are shown for the period from October 1, 1993, through November 29, 1995. Recharge water was injected from June 2, 1994, through July 29, 1994, and from June 14, 1995, through September 13, 1995. The cumulative volume of injected water and the injection rates into the aquifer are presented for the periods of recharge. Water-quality data were collected from screening, detailed, and plume-monitoring sampling programs. Screening water-quality data for six observation wells are presented. These data include primarily field parameters and common ions. The four detailed sampling sites represent the quality of untreated water, treated water, and ground water from the Warren aquifer. Data presented for the detailed sampling program include field parameters, bacteria counts, and concentrations of common ions, solids, nutrients, trace elements, radiometrics, total organic carbon, herbicides, insecticides, and volatile organic compounds. Water-quality data for the plume-monitoring sampling program were collected from 25 sites during injection of recharge water into the Warren aquifer in 1994 and 1995. The data for the plume-monitoring program include primarily field parameters and common ions. Data for quality-assurance samples also are presented.

Open-File Report↗

Ground-Water Budgets for the Wood River Valley Aquifer System, South-Central Idaho, 1995-2004

The Wood River Valley contains most of the population of Blaine County and the cities of Sun Valley, Ketchum, Haley, and Bellevue. This mountain valley is underlain by the alluvial Wood River Valley aquifer system which consists of a single unconfined aquifer that underlies the entire valley, an underlying confined aquifer that is present only in the southernmost valley, and the confining unit that separates them. The entire population of the area depends on ground water for domestic supply, either from domestic or municipal-supply wells, and rapid population growth since the 1970s has caused concern about the long-term sustainability of the ground-water resource. To help address these concerns this report describes a ground-water budget developed for the Wood River Valley aquifer system for three selected time periods: average conditions for the 10-year period 1995-2004, and the single years of 1995 and 2001. The 10-year period 1995-2004 represents a range of conditions in the recent past for which measured data exist. Water years 1995 and 2001 represent the wettest and driest years, respectively, within the 10-year period based on precipitation at the Ketchum Ranger Station. Recharge or inflow to the Wood River Valley aquifer system occurs through seven main sources (from largest to smallest): infiltration from tributary canyons, streamflow loss from the Big Wood River, areal recharge from precipitation and applied irrigation water, seepage from canals and recharge pits, leakage from municipal pipes, percolation from septic systems, and subsurface inflow beneath the Big Wood River in the northern end of the valley. Total estimated mean annual inflow or recharge to the aquifer system for 1995-2004 is 270,000 acre-ft/yr (370 ft3/s). Total recharge for the wet year 1995 and the dry year 2001 is estimated to be 270,000 acre-ft/yr (370 ft3/s) and 220,000 acre-ft/yr (300 ft3/s), respectively. Discharge or outflow from the Wood River Valley aquifer system occurs through five main sources (from largest to smallest): Silver Creek streamflow gain, ground-water pumpage, Big Wood River streamflow gain, direct evapotranspiration from riparian vegetation, and subsurface outflow (treated separately). Total estimated mean 1995-2004 annual outflow or discharge from the aquifer system is 250,000 acre-ft/yr (350 ft3/s). Estimated total discharge is 240,000 acre-ft/yr (330 ft3/s) for both the wet year 1995 and the dry year 2001. The budget residual is the difference between estimated ground-water inflow and outflow and encompasses subsurface outflow, ground-water storage change, and budget error. For 1995-2004, mean annual inflow exceeded outflow by 20,000 acre-ft/yr (28 ft3/s); for the wet year 1995, mean annual inflow exceeded outflow by 30,000 acre-ft/yr (41 ft3/s); for the dry year 2001, mean annual outflow exceeded inflow by 20,000 acre-ft/yr (28 ft3/s). These values represent 8, 13, and 8 percent, respectively, of total outflows for the same periods. It is difficult to differentiate the relative contributions of the three residual components, although the estimated fluctuations between the wet and dry year budgets likely are primarily caused by changes in ground-water storage. The individual components in the wet and dry year ground-water budgets responded in a consistent manner to changes in precipitation and temperature. Although the ground-water budgets for the three periods indicated that ground-water storage is replenished in wet years, statistical analyses by Skinner and others (2007) suggest that such replenishment is not complete and over the long term more water is removed from storage than is replaced. In other words, despite restoration of water to ground-water storage in wet years, changes have occurred in either recharge and (or) discharge to cause ground-water storage to decline over time. Such changes may include, but are not limited to: lining or abandoning canals and ditches, conversion of surface-water irriga

Scientific Investigations Report↗

Ground-water discharge determined from estimates of evapotranspiration, Death Valley regional flow system, Nevada and California

The Death Valley regional flow system (DVRFS) is one of the larger ground-water flow systems in the southwestern United States and includes much of southern Nevada and the Death Valley region of eastern California. Centrally located within the ground-water flow system is the Nevada Test Site (NTS). The NTS, a large tract covering about 1,375 square miles, historically has been used for testing nuclear devices and currently is being studied as a potential repository for the long-term storage of high-level nuclear waste generated in the United States. The U.S. Department of Energy, as mandated by Federal and State regulators, is evaluating the risk associated with contaminants that have been or may be introduced into the subsurface as a consequence of any past or future activities at the NTS. Because subsurface contaminants can be transported away from the NTS by ground water, components of the ground-water budget are of great interest. One such component is regional ground-water discharge. Most of the ground water leaving the DVRFS is limited to local areas where geologic and hydrologic conditions force ground water upward toward the surface to discharge at springs and seeps. Available estimates of ground-water discharge are based primarily on early work done as part of regional reconnaissance studies. These early efforts covered large, geologically complex areas and often applied substantially different techniques to estimate ground-water discharge. This report describes the results of a study that provides more consistent, accurate, and scientifically defensible measures of regional ground-water losses from each of the major discharge areas of the DVRFS. Estimates of ground-water discharge presented in this report are based on a rigorous quantification of local evapotranspiration (ET). The study identifies areas of ongoing ground-water ET, delineates different ET areas based on similarities in vegetation and soil-moisture conditions, and determines an ET rate for each delineated area. Each area, referred to as an ET unit, generally consists of one or more assemblages of local phreatophytes or a unique moist soil environment. Ten ET units are identified throughout the DVRFS based on differences in spectral-reflectance characteristics. Spectral differences are determined from satellite imagery acquired June 21, 1989, and June 13, 1992. The units identified include areas of open playa, moist bare soils, sparse to dense vegetation, and open water. ET rates estimated for each ET unit range from a few tenths of a foot per year for open playa to nearly 9 feet per year for open water. Mean annual ET estimates are computed for each discharge area by summing estimates of annual ET from each ET unit within a discharge area. The estimate of annual ET from each ET unit is computed as the product of an ET unit's acreage and estimated ET rate. Estimates of mean annual ET range from 450 acre-feet in the Franklin Well area to 30,000 acre-feet in Sarcobatus Flat. Ground-water discharge is estimated as annual ET minus that part of ET attributed to local precipitation. Mean annual ground-water discharge estimates range from 350 acre-feet in the Franklin Well area to 18,000 acre-feet in Ash Meadows. Generally, these estimates are greater for the northern discharge areas (Sarcobatus Flat and Oasis Valley) and less for the southern discharge areas (Franklin Lake, Shoshone area, and Tecopa/ California Valley area) than those previously reported.

California;Nevada↗

User Guide and Documentation for Five MODFLOW Ground-Water Modeling Utility Programs

This report documents five utility programs designed for use in conjunction with ground-water flow models developed with the U.S. Geological Survey's MODFLOW ground-water modeling program. One program extracts calculated flow values from one model for use as input to another model. The other four programs extract model input or output arrays from one model and make them available in a form that can be used to generate an ArcGIS raster data set. The resulting raster data sets may be useful for visual display of the data or for further geographic data processing. The utility program GRID2GRIDFLOW reads a MODFLOW binary output file of cell-by-cell flow terms for one (source) model grid and converts the flow values to input flow values for a different (target) model grid. The spatial and temporal discretization of the two models may differ. The four other utilities extract selected 2-dimensional data arrays in MODFLOW input and output files and write them to text files that can be imported into an ArcGIS geographic information system raster format. These four utilities require that the model cells be square and aligned with the projected coordinate system in which the model grid is defined. The four raster-conversion utilities are * CBC2RASTER, which extracts selected stress-package flow data from a MODFLOW binary output file of cell-by-cell flows; * DIS2RASTER, which extracts cell-elevation data from a MODFLOW Discretization file; * MFBIN2RASTER, which extracts array data from a MODFLOW binary output file of head or drawdown; and * MULT2RASTER, which extracts array data from a MODFLOW Multiplier file.

Techniques and Methods↗

Selected reports that include computer programs produced by the US Geological Survey for simulation of ground-water flow and quality

A summary list of reports that document numerical models that simulate ground-water flow and quality is presented. The list documents the reference by giving a description of each model program, its numerical features, a qualitative expression of the number of past applications and where to obtain a copy. All reports included in the list have been published or developed by the U.S. Geological Survey and most contain listings of the computer programs. (Author 's abstract)

Water-Resources Investigations Report↗

Analysis of water-level fluctuations in Wisconsin wells

More than 60 percent of the residents of Wisconsin use ground water as their primary water source. Water supplies presently are abundant, but ground-water levels continually fluctuate in response to natural factors and human-related stresses. A better understanding of the magnitude, duration, and frequency of past fluctuations, and the factors controlling these fluctuations may help anticipate future changes in ground-water levels. This report presents the results of statistical analyses of historical ground-water level fluctuations in Wisconsin. Short- and long-term fluctuations are discussed in terms of their relation to components of the hydrogeologic system. Water-level measurements from 124 wells with at least 20 years of record each were used in the study. The mean, highest and lowest monthly mean, median, and selected quantiles were obtained using the SAS Proc Univariate procedure. The frequency values from the Univariate table were used to construct stage-duration graphs. Pearson Type ill frequency analyses were used to obtain probabilities of exceedance of particular water levels. The data were divided into seasonal data sets for each well. The stage-duration and Pearson Type III analyses are based on past fluctuations but may be useful for estimating future water-level changes under similar conditions. Multiple-regression analyses were run on data from groups of wells representing different ground-water districts. The SAS Proc Stepwise method was used. The regression model used average annual amplitude as the dependent variable and mean water level, mean annual precipitation, standard deviation of the seasonal mean precipitation, aquifer type, and topographic setting as the independent variables.This procedure produced different regression equations for each hydrogeologic district. Regression analyses also were done on data from groups of wells representing different aquifers. These regression models used average annual amplitude as the dependent variable and mean water level, topographic setting, and standard deviation of seasonal mean precipitation as the independent variables. Because of the many factors influencing ground-water level fluctuations, it was difficult to obtain a regression model that accurately reproduced average annual amplitude. The results of the regression analyses are helpful in recognizing the important variables; however, the equations are not effective in predicting the amplitude of a particular well because local conditions were omitted in the regional analyses. Hydrographs of average annual water level and frequency distribution analyses of annual maximum and minimum water levels were inspected for possible long-term trends. Analysis of annual maximum and minimum water levels indicates several periods in the annual cyclic fluctuations-two periods of recession (winter and summer), and two periods of rising levels (spring and fall). Usually, water levels are lowest in late winter and highest in spring for every annual cycle. The summer-fall minimum and the fall maximum are less distinct and do not occur every year. A composite frequency analysis of extreme annual water levels on 71 of the wells shows that the lowest levels most frequently occur in December, February, or March. However, the record low usually occurs in August, September, or October during drought. Ground-water levels most often peak in May, April, or June. In the fan they may peak from September through December, depending upon complexities of meteorological, geomorphological, and geological factors. The long-term cyclicity of ground-water level fluctuations is shown on hydrographs of wells Sw-7, Ln-25a, Mt-7, Ju-8, and Ju-98. Seasonal variations that tend to obscure the long-term trends are eliminated by plotting the average annual water levels. The hydrographs are similar even though the wells are 80 to 100 miles apart and constructed in different geologic materials. The long-term trends and the duration of the cycles apparently depend little on the location and on the lithologic composition of the aquifers, but rather on precipitation. The hydrographs show several periods of welldefined peaks and lows. The ground-water levels reached peaks in 1946, 1952, 1960, 1966, 1973, 1979. The average interval between these peaks is 6.6 years. The low levels occurred in 1949, 1955-59, 1964, 1970, and 1977; average interval between the low levels is 7.0 years, which is similar to that for the high levels. Long-term trends are apparent on hydrographs of wells Br-46, Mr-2S, Pt-276, Ro-3, and Ve-8. The trend of average annual water levels has been generally increasing since the late 1950's and is in general agreement with the increasing trend of precipitation. Hydrographs of well Ve-8, which has the longest period of record in Wisconsin, indicate that the generally rising trend started even earlier at the end of an extensive drought period in the 1930's.

Wisconsin↗

Geology and ground-water resources of Sumner County, Kansas

This report describes the geography, geology, and ground-water resources of Sumner County in south-central Kansas. The hydrologic and geologic data upon which this report is based were obtained in the field during the summers of 1955 and 1956. Records of 300 wells and 2 springs, chemical analyses of 219 water samples from wells and test holes and of 15 from streams, and logs of 362 wells and test holes are included in tables. Sumner County has an area of 1,183 square miles and lies in the Wellington Lowland and Arkansas River Lowlands of the Central Lowland physiographic province. It is drained by Arkansas River, Ninnescah River, and Chikaskia River and their tributaries. The land surface in general is a southeastward-sloping, gently rolling plain. The average annual precipitation at Wellington is about 31 inches. Wheat fanning is the principal industry of the county, and oil is the chief natural resource. The Wellington Formation, of Permian age, crops out in the eastern two-thirds of the county except where it is covered by Pleistocene deposits. The Ninnescah Shale (Permian) overlies the Wellington Formation and crops out in parts of the western third of the county. The Permian rocks yield small quantities of hard water to wells. Pleistocene sand and gravel deposits of Nebraskan age are present in the northwestern corner of the county and yield moderate quantities of good water to wells. Discontinuous deposits of Kansan or Illinoisan age, locally mantled by colluvium, forms terraces in southern and eastern Sumner County, and may yield moderate quantities of water. Wisconsinan terrace deposits and Recent alluvium along the major streams yield large quantities of water. Colluvium and dune sand are unimportant as sources of water but may facilitate recharge. Maps of Sumner County included in this report show the outcrop areas of the formations, geologic cross sections, the shape and slope of the water table, the locations of wells and test holes for which records are given, and the distribution of chloride in water samples. The ground-water reservoir is recharged principally from rain and snow that fall within the county, by percolation from streams and other surface bodies of water, and by underflow from adjacent areas. Water is discharged from the ground-water reservoir by seepage into streams, by transpiration and evaporation, by movement into adjacent areas, and by wells. Water is pumped from wells for domestic, stock, municipal, industrial, and irrigation use. Irrigation from wells is most extensive in the valley of Arkansas River, in which area further development is most probable. Chemical analyses of samples of water from Sumner County indicate that the quality varies greatly from place to place. Sulfate is common in water from the Wellington Formation and Ninnescah Shale. Water from Pleistocene deposits is generally suitable for most uses except in local areas where it contains excessive chloride.

Kansas Geological Survey Bulletin↗

Hydrogeologic data for the Upper Connecticut River Basin, Connecticut

This report contains geologic, ground-water, and quality-of-water data collected and compiled for a water resources investigation of the upper Connecticut River basin, Connecticut by the U.S. Geological Survey in financial cooperation with the Connecticut Department of Environmental Protection. These data, together with surface-water data, were collected at sites shown on plate A and are, with exceptions discussed below, presented herein. The interpretation of these data will be published separately in Connecticut Water Resources Bulletin No. 24. As defined for this investigation, the upper Connecticut River basin is a 508-square-mile area in north-central Connecticut (see front cover and plate A) drained by the Connecticut River and its tributaries including the Farmington River downstream from the community of Tariffville. The basin includes all or parts of the following 30 towns: Avon, Bloomfield, Bolton, Cromwell, East Granby, East Hampton, East Hartford, East Windsor, Ellington, Enfield, Farmington, Glastonbury, Hartford, Manchester, New Brltain, Newington, Plainville, Portland, Rocky Hill, Simsbury, Somers, South Windsor, Stafford, Suffield, Tolland, Vernon, West Hartford, Wethersfield, Windsor, and Windsor Locks. The data compiled for this investigation consist of those collected specifically for the study during the period July 1967 - December 1969 and those collected during previous investigations. Many records of wells and test holes in thus report were published in Connecticut Water Resources Bulletin No. 4. This report is out of print, therefore these previously published records, together with newer ones, are published in this report to provide a readily available source of ground-water information. Previously published well numbers have been retained and are those published in this report. However, test holes previously published as wells have been assigned test-hole numbers; the former well number Is noted in table 3.

Connecticut↗

Ground-water data for Michigan 1982

Water levels, locations, depths, and aquifers tapped are given for 117 observation wells. Tabulated data include extremes of water levels for 1982 and for the period of record, pumpage of most major ground-water users in the State, and quality data on selected wells. The largest reported user of ground-water, the city of Lansing, pumped 8.2 billion gallons from the Saginaw Formation and glacial deposits.

Michigan↗

Water levels in observation wells in Santa Barbara County, California, 1963

The U.S. Geological Survey, in cooperation with the Santa Barbara County Water Agency, continued the study of the ground-water resources of Santa Barbara County (fig. 1) in 1963. As part of the study, the Geological Survey made monthly water-level measurements in 247 wells; 17 of which were equipped with automatic water-level recorders. These measurements and measurements made by the Santa Maria Valley Water Conservation District are included in this report— In addition, the U.S. Bureau of Reclamation measured the water levels in wells along the Santa Ynez River between Cachuma Dam and Rucker Crossing, but the measurements have not been included herein. In addition to the observation-well program, the Geological Survey is preparing interpretive reports on the ground-water conditions in the Ellwood-Gaviota area, the Lompoc and Santa Ynez upland areas of the Santa Ynez River basin, the Santa Barbara-Summerland area, and the Santa Maria Valley. The basic data from which these reports are being prepared can be consulted at the Santa Barbara office of the Geological Survey. This report was prepared by the Geological Survey, Water Resources Division, under the general supervision of Fred Kunkel, district geologist in charge of ground-water investigations In California, and under the immediate supervision of C. P. Zones, geologist in charge of the Santa Barbara subdistrict office. Measurements for the period 1941-55 were published in U.S. Geological Survey water-supply papers; measurements for the period 1956-62 were released locally in duplicated form.' A report by G. A. LaRocque, Jr., and others (1950) contains descriptions of 2,246 wells in the ground-water basins of the county in 1942. It also contains many water-level measurements made before 1942 by the city of Santa Barbara, the Santa Maria Valley Water Conservation District, the San Joaquin Power Division of the Pacific Gas and Electric Co., the Union Sugar Co., the Union Oil Co., and other organizations and individuals. Comprehensive reports on the geology and ground-water resources of the Santa Ynez River basin (Upson, Thomasson, and others, 1951; Wilson, 1959), the south-coast basins (Upson and others, 1951), the Santa Maria Valley area (Worts, 1951), the Cuyama Valley (Upson and Worts, 1951) and the San Antonio Creek valley (Muir; 1964) were published as Geological Survey water-supply papers. A report on stream runoff and ground-water storage capacity of the Santa Ynez River valley (Troxell and Wilson, 1952) was released to the open file in October 1952. A complete bibliography of reports of investigations made by the Water Resources Division, U.S. Geological Survey, in Santa Barbara County since 1940 is included in this report.

California↗

Selected natural attenuation monitoring data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2001

Previous investigations have shown that natural attenuation and biodegradation of chlorinated volatile organic compounds (CVOCs) are substantial in shallow ground water beneath the 9-acre former landfill at Operable Unit 1 (OU 1), Naval Undersea Warfare Center (NUWC), Division Keyport, Washington. The U.S. Geological Survey (USGS) has continued to monitor ground-water geochemistry to assure that conditions remain favorable for contaminant biodegradation. This report presents the ground-water geochemical and selected CVOC data collected at OU 1 by the USGS during June 11-14, 2001 in support of the long-term monitoring for natural attenuation. Overall, the June 2001 data indicate that redox conditions in the upper aquifer remain favorable for reductive dechlorination of CVOCs because strongly reducing conditions persisted beneath much of the former landfill. Redox conditions in the intermediate aquifer down gradient of the landfill appear to have become more favorable for reductive dechlorination because June 2001 dissolved hydrogen concentrations indicated strongly reducing conditions there for the first time. Although changes in redox conditions were observed at certain wells during 2001, a longer monitoring period is needed to ascertain if phytoremediation activities are affecting the ground-water chemistry. A minor change to future monitoring is proposed. Filtered organic carbon (previously referred to as dissolved, and defined as that which passes through a 0.45-micrometer membrane filter) should be analyzed in the future rather than unfiltered (previously referred to as total) organic carbon because the filtered analysis may be a better measure of bioavailable organic carbon. Unfiltered and filtered organic carbon data were collected during June 2001 for comparison. Filtered organic carbon data collected in the future could be reasonably compared with historical unfiltered organic carbon data by multiplying the historical data by a factor of about 0.9.

Open-File Report↗

Selected Natural Attenuation Monitoring Data, Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington, June 2005

Previous investigations have shown that natural attenuation and biodegradation of chlorinated volatile organic compounds (VOCs) are substantial in shallow ground water beneath the 9-acre former landfill at Operable Unit 1 (OU-1), Naval Undersea Warfare Center, Division Keyport, Washington. The U.S. Geological Survey (USGS) has continued to monitor ground-water geochemistry to assure that conditions remain favorable for contaminant biodegradation. This report presents the ground-water geochemical and selected VOC data collected at OU-1 by the USGS during June 21-24, 2005, in support of long-term monitoring for natural attenuation. For June 2005, the strongly reducing conditions (sulfate reduction and methanogenesis) most favorable for reductive dechlorination of chlorinated VOCs were detected in fewer upper-aquifer wells than were detected during 2004. Redox conditions in ground water from the intermediate aquifer just downgradient of the landfill remained somewhat favorable for reductive dechlorination. Overall, the changes in redox conditions observed at individual wells have not been consistent or substantial throughout either the upper or the intermediate aquifers. In apparent contrast to changes in redox conditions, the chlorinated VOC concentrations were lower than previously measured in many of the piezometers in the northern phytoremediation plantation. The decrease in contaminant concentrations beneath the northern plantation and the end-product (ethane and ethene) evidence for reductive dechlorination are consistent with 2000-04 results. In the southern phytoremediation plantation, changes in chlorinated VOC concentrations were variable. Most notable was a substantial decrease in the sum of trichloroethene, cis-1,2-dichloroethene, and vinyl chloride concentrations at piezometer P1-9 from 75,000 to 1,000 micrograms per liter between 2004 and 2005. The high concentrations of the reductive dechlorination end-products ethane and ethene measured at the most contaminated sites (P1-6 and P1-7), as well as measurable concentrations at sites P1-9 and P1-10, are reliable evidence that reductive dechlorination of chlorinated VOCs is ongoing in the southern plantation. In the 10 passive-diffusion samplers deployed beneath the marsh stream, the highest chlorinated VOC concentrations measured were at a site (S-4) about midway along the sampled stream reach. In 2005, the sum of trichloroethene, cis-1,2-dichloroethene, and vinyl chloride concentrations increased nearly twofold in comparison to 2004. It is not certain that the apparent increase in concentrations is representative of site conditions. However, the chlorinated VOC concentrations have increased each time at the two most contaminated passive-diffusion sampler sites that have been sampled for multiple years. In the marsh stream, chlorinated VOC concentrations in surface water were low at the site (SW-S6) near the upgradient margin of the former landfill. Concentrations in the stream increased substantially after flowing past the southern phytoremediation plantation to the downstream site (MA-12). Overall, the 2005 data were consistent with previous findings of continued biodegradation of chlorinated VOCs in ground water, along with continued discharge of some chlorinated VOCs to surface water in the marsh stream.

Open-File Report↗

Hydrogeologic data for the Quinnipiac River basin, Connecticut

This report contains geologic, ground-water, and quality-of-water data collected for the ground-water part of a water-resources inventory of the Quinnipiac River basin, Connecticut. The study was made by the U.S. Geological Survey in fiscal cooperation with the Connecticut Department of Environmental Protection. Collection sites for data used in the study are shown in plate A. A companion report interprets the ground-water, quality-of-water, and surfacewater data collected for the study (Connecticut Water Resources Bulletin No. 27, in parparation). The Quinnipiac River basin~ as used in this report~ is a 360-square-mile area in south-central Connecticut drained principally by the Quinnipiac River and its tributaries and several smaller streams~ which drain directly to Long Island Sound. (See front cover and plate A.) The study area includes all or parts of the following towns: Ansonia, Berlin, Bethany, Branford, Bristol, Cheshire, Derby, Durham, East Haven, Farmington, Guilford, Hamden, Meriden, Middlefield, Middletown, Milford, New Britain, New Haven, North Branford, North Haven, Orange, Plainville, Prospect, Southington, Wallingford, West Haven, Wolcott, and Woodbridge. Data collected for this investigation from July 1969 to December 1971 were supplemented by data collected during previous investigations. This report includes some records of wells and test holes published in Connecticut Water Resources Bulletin No. 5 and also includes some records used but not published in Connecticut Water Resources Bulletin No. 14. Table 5 contains old but previously unpublished analyses of water from wells in New Haven collected primarily from 1938 to 1949. Ownership of the sampled wells, as shown in table 1 and table 5, was determined at the time of the original inventory, and this information may now be outdated. Many of these wells have been destroyed since they were last sampled and others, though still in existence, are no longer in use.

Connecticut↗

Research opportunities in interdisciplinary ground-water science in the U.S. Geological Survey

This report is written for the scientifically literate reader but is not limited to those who are involved in ground-water science. The report is intended to encourage U.S. Geological Survey scientists to develop a sense of excitement about ground-water science in the agency, to inform scientists about existing and potential ground-water science opportunities, and to engage scientists and managers in interdisciplinary discussions and collaboration. The report is intended for use by U.S. Geological Survey and Department of the Interior management to formulate long-term ground-water science programs and to continue sustained support of ground-water monitoring and research, some of which may not have an immediate impact. Finally, the report can be used to communicate the U.S. Geological Survey's vision of ground-water science to Congress, partners, other agencies, and the research community at large with the goals of enhancing collaborative opportunities, sharing information, and maintaining dialogue regarding the directions of U.S. Geological Survey ground-water science.

Circular↗

Water-resources-related information for the St. Croix Reservation and vicinity, Wisconsin

The St. Croix Chippewa Tribe is interested in documenting water-quality conditions in lakes and streams adjacent to their Reservation lands in northwestern Wisconsin and developing management plans to protect these water resources. This report provides the Tribe with a retrospective summary and analysis of available water-resources-related information for their Reservation and vicinity. The study area is divided into four main watersheds: Big Round Lake, Clam River at Clam Lake Outlet, Yellow River at Danbury, and Loon Creek at Danbury. The Clam River Watershed includes the subwatersheds of Bashaw and Sand Lakes. The Yellow River Watershed includes the subwatersheds of Big Sand and Gaslyn Lakes. In all, 41 surface-water studies or reports that include information relevant to the study area were identified. Most of the surface-water studies were regional or statewide summaries. Fifteen of these studies include lake information and 36 include stream information. Twenty-eight of the studies include water-quality data and 16 include information describing aquatic biology. Water- and sediment-quality data were obtained for 80 lakes and 23 streams in the study area. Lake information includes data for 101 water-quality characteristics from nearly 4,300 water and sediment analyses of samples collected between 1972 and 1998. Stream information summarized in this report includes data for 135 water-quality characteristics and nearly 4,500 water and sediment analyses of samples collected at 23 sites between 1964 and 1999. A total of 41 ground-water studies or reports that include information relevant to the study area were identified. Most of the ground-water studies were regional or statewide summaries. Of the 41 studies, 33 include water-quality information, 9 include information regarding water use, and 23 provide descriptions of geology and aquifer characteristics relevant to the study area. Water-quality information for 773 wells was compiled. Most of the sampled wells were used for drinking water, and most of the drinking-water wells represent domestic supplies. Water-quality data summarized in this report represent 270 characteristics and more than 10,300 analyses of samples collected from drinking-water wells between 1911 and 1999; however, most of the water-quality data were collected after about 1990.

Wisconsin↗