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National water quality assessment of the Georgia-Florida Coastal Plain study unit — Water withdrawals and treated wastewater discharges, 1990

The Georgia-Florida Coastal Plain study unit covers nearly 62,600 square miles along the southeastern United States coast in Georgia and Florida. In 1990, the estimated population of the study unit was 9.3 million, and included all or part of the cities of Atlanta, Jacksonville, Orlando, Tampa, and St. Petersburg. Estimated freshwater withdrawn in the study unit in 1990 was nearly 5,075 million gallons per day. Ground-water accounted for more than 57 percent of the water withdrawn during 1990 and the Floridan aquifer system provided nearly 91 percent of the total ground-water withdrawn. Surface-water accounted for nearly 43 percent of the water withdrawn in the study unit in 1990 with large amounts of withdrawals from the Altamaha River, Hillsborough River, the Ocmulgee River, the Oconee River, the St. Johns River, and the Suwannee River. Water withdrawn for public supply in the Georgia-Florida Coastal Plain study unit in 1990 totaled 1,139 million gallons per day, of which 83 percent was ground water and 17 percent was surface water. Self-supplied domestic withdrawals in the Georgia-Florida Coastal Plain study unit in 1990 totaled nearly 230 million gallons per day. Ground water supplied over 80 percent of the study units population for drining water purposes; nearly 5.8 million people were served by public supply and 1.8 million people were served by self-supplied systems. Water withdrawn for self-supplied domestic use in Georgia and Florida is derived almost exclusively from ground water, primarily because this source can provide the quantity and quality of water needed for drinking purposes. Nearly 1.7 million people served by public supply utilized surface water for their drinking water needs. Water withdrawn for self-supplied commercial-industrial uses in the study unit in 1990 totaled 862 million gallons per day, of which 93 percent was ground water and 7 percent was surface water. Water withdrawn for agriculture purposes in the study unit in 1990 totaled 1,293 million gallons per day, of which 69 percent was ground water and 31 percent was surface water. An estimated 1.254 millon acres were irrigated within the study unit during 1990. Water withdrawn for thermoelectric power generation in the study unit in 1990 totaled 1,552 million gallons per day, of which 99 percent was surface water and 1 percent was ground water. An additional 6,919 million gallons per day of saline surface water were withdrawn for thermoelectric power generation in 1990, solely for cooling purposes. Treated wastewater discharged within the Georgia-Florida Coastal Plain study unit totaled nearly 1,187 million gallons per day in 1990. Of the total water discharged, 58 percent was discharged directly into surface water and the remaining 42 percent was discharged to ground water (through drain fields, injection wells, percolation ponds or spray fields). Domestic wastewater facilities discharged in the study unit totaled nearly 789 million gallons per day, industrial wastewater facilities discharged 213 million gallons per day, and releases from septic tanks was estimated at 185 million gallons per day. More than 1.3 million septic tanks were estimated in use within the study unit in 1990.

Florida, Georgia↗

Contamination of wells completed in the Roubidoux aquifer by abandoned zinc and lead mines, Ottawa County, Oklahoma

The Roubidoux aquifer in Ottawa County Oklahoma is used extensively as a source of water for public supplies, commerce, industry, and rural water districts. Water in the Roubidoux aquifer in eastern Ottawa County has relatively low dissolved-solids concentrations (less than 200 mg/L) with calcium, magnesium, and bicarbonate as the major ions. The Boone Formation is stratigraphically above the Roubidoux aquifer and is the host rock for zinc and lead sulfide ores, with the richest deposits located in the vicinity of the City of Picher. Mining in what became known as the Picher mining district began in the early 1900's and continued until about 1970. The water in the abandoned zinc and lead mines contains high concentrations of calcium, magnesium, bicarbonate, sulfate, fluoride, cadmium, copper, iron, lead, manganese, nickel, and zinc. Water from the abandoned mines is a potential source of contamination to the Roubidoux aquifer and to wells completed in the Roubidoux aquifer. Water samples were collected from wells completed in the Roubidoux aquifer in the Picher mining district and from wells outside the mining district to determine if 10 public supply wells in the mining district are contaminated. The chemical analyses indicate that at least 7 of the 10 public supply wells in the Picher mining district are contaminated by mine water. Application of the Mann-Whitney test indicated that the concentrations of some chemical constituents that are indicators of mine-water contamination are different in water samples from wells in the mining area as compared to wells outside the mining area. Application of the Wilcoxon signed-rank test showed that the concentrations of some chemical constituents that are indicators of mine-water contamination were higher in current (1992-93) data than in historic (1981-83) data, except for pH, which was lower in current than in historic data. pH and sulfate, alkalinity, bicarbonate, magnesium, iron, and tritium concentrations consistently indicate that the Cardin, Commerce 1, Commerce 3, Picher 2, Picher 3, Picher 4, and Quapaw 2 wells are contaminated.

Oklahoma↗

Water-quality assessment of the Connecticut, Housatonic, and Thames River Basins study unit: Analysis of available data on nutrients, suspended sediments, and pesticides, 1972-92

This retrospective report examines available nutrient, suspended sediment, and pesticide data in surface and ground water in the Connecticut, Housatonic and Thames Rivers Study Unit of the National Water-Quality Assessment Program. The purpose of this study is to improve the understanding of natural and anthropogenic factors affecting water quality in the study unit. Waterquality data were acquired from various sources, primarily, the U.S. Geological Survey and the U.S. Environmental Protection Agency. The report examines data for water years 1972-92, focusing on 1980-92, although it also includes additional data from as early as 1905. The study unit lies within the New England Physiographic Province and altitudes range from sea level in coastal Connecticut to 6,288 feet above sea level at Mount Washington, New Hampshire. Two major aquifer types underlie the study unit unconsolidated glacial deposits and fractured bedrock. The climate generally is temperate and humid, with four distinct seasons. Average annual precipitation ranges from 34 to 65 inches. The study unit has a population of about 4.5 million, which is most highly concentrated in southwestern Connecticut and along the south-central region of the Connecticut River Valley. Surface-water-quality data were screened to provide information about sites with adequate numbers of analyses (50) over sufficiently long periods (1980-90) to enable valid statistical analyses. In order to compare effects of different types of land use on surface-water quality, examination of data required application of several statistical and graphical techniques, including mapping, histograms, boxplots, concentration-discharge plots, trend analysis, and load estimation. Spatial and temporal analysis of surface-water-quality data indicated that, with a single exception, only stations in the Connecticut water-quality network had sufficient data collected over adequately long time periods to use in detailed analyses. Ground-water nutrient and pesticide data were compiled from several Federal and State agencies, primarily the U.S. Geological Survey, U.S. Environmental Protection Agency, and Connecticut Department of Health Services. Nutrient data were available for several thousand wells; nitrite plus nitrate as nitrogen was the most commonly reported constituent. Most wells with nutrient data are in Massachusetts and Connecticut. Relative to nutrient data in ground and surface water, pesticide data are less common. Pesticide data were available for slightly more than 200 surface-water sites and less than 500 wells; about 95 percent of the wells are completed in stratified-drift or till aquifers. Data for 81 pesticide compounds were available in various data bases. 2,4-D and silvex were the most commonly detected herbicides in surface water and dieldrin and diazinon were the most commonly detected insecticides. Most surface-water pesticide samples and detections are from bed sediment, but much of the data are not recent. Ethylene dibromide (EDB), a soil fumigant used in tobacco farming was detected in 268 wells in a 50 square-mile area of north-central Connecticut; EDB contamination also was detected in wells in Massachusetts. Atrazine, an herbicide commonly used in corn farming, commonly was detected in wells installed in tilled agricultural fields. Corn herbicides were commonly detected in the northern part of the study unit, although the sampling has been less frequent than in the southern part of the study unit. Pesticides were seldom detected in public-supply wells in Connecticut. Urban sites with relatively high population densities and high concentrations of dischargers were characterized by having the highest nutrient concentrations and loads when adjusted for differences in drainage area or population. Particularly, the Pequabuck, Naugatuck, and Quinnipiac River Basins were characterized by high nutrient concentrations median total nitrogen concentrations ranged from 3.3 to 4.2 mg/L (milligrams per liter) and median total phosphorus concentrations ranged from 0.42 to 0.8 mg/L. In contrast, the predominantly forested and low density residential land-use sites, such as Saugatuck and Salmon River Basins, were characterized by low nutrient concentrations median total nitrogen ranged from 0.50 to 0.60 mg/L and median total phosphorus concentrations ranged from 0.01 to 0.02 mg/L. Estimated total nitrogen loadings in median discharge years ranged from 940 kilograms per square mile at the Salmon River near East Hampton, Conn., to 5,800 kilograms per square mile at the Naugatuck River at Beacon Falls, Conn. Water quality, in terms of nutrient concentrations and areally adjusted loadings, for sites with large drainage basins integrating a wide variety of land-use categories fell between the extremes of the urban and forested sites total nitrogen was 1,400 kilograms per square mile per year at the Connecticut River at Thompsonville, Conn. Nitrate concentrations in ground water occasionally exceeded the safe drinking-water standard of 10 mg/L as nitrogen. The greatest number of detections exceeding the standard, however, were not in public-water supplies but in shallow observation wells in agricultural settings (the most frequently sampled type of well). None of the public-supply wells in Massachusetts exceeded the standard. Although nitrate concentrations for Vermont and New Hampshire generally were low, few data were available and those were seldom reported on the basis of drainage basin, making analysis difficult. Trend analysis indicated that flow-adjusted concentrations of total and dissolved phosphorus generally decreased during the period of analysis, however, total nitrogen did not change substantially. Decreases in ammonia concentrations with time were usually accompanied by increases in nitrate, suggesting improvements in sewage treatment. The lack of adequate data from more or less exclusively agricultural areas points to the need for further study of the effects of fanning on surface-water quality in the study unit. Furthermore, additional information is needed on the rates, transformations, and movements of nutrients and other materials through and between the aquatic and terrestrial components of the study unit.

Connecticut, Massachusetts, New Hampshire, Quebec,↗

Water resources of the Wind River Indian Reservation, Wyoming

Existing data were used in conjunction with onsite measurements to evaluate the water resources on the Wind River Indian Reservation, Wyoming. The reservation is located mainly in the Wind River drainage basin. Ground water is used for public- supply, domestic, agricultural, and industrial purposes, and potentially for irrigation. Deposits of Quaternary age provide water for domestic and public-supply uses. Median well yields from different types of Quaternary deposits ranged from 6 to 20 gallons per minute. The Wind River Formation of Tertiary age is a major source of water for domestic and public-supply uses; well yields ranged from 0.1 to 350 gallons per minute. For the Tensleep Sandstone and Madison Limestone of Paleozoic age, wells might yield as much as 1,000 gallons per minute. The dissolved-solids concentration of water from the Little Wind River and Popo Agie River flood-plain alluvium near mountains was generally less than 400 mg/L (milligrams per liter), but with increasing distance from mountains, the range was about 600 to about 750 mg/L. Dissolved-solids concentrations of water in the Wind River Formation ranged from 211 to 5,110 mg/L. Streams provide most water used for irrigation. Discharge records from streamflow-gaging stations indicate flow characteristics of streams on the reservation are extremely variable. Average annual runoff was 122 to 1,150 acre-feet per square mile on perennial streams with gaging stations. Near the mountains, most perennial streams had dissolved-solids concentrations less than 200 mg/L, and with increasing distance from the mountains, concentrations were about 400 to 600 mg/L.

Water-Resources Investigations Report↗

Evaluation of saltwater intrusion and travel time in the Atlantic City 800-foot sand, Cape May County, New Jersey, 1992, by use of a coupled-model approach and flow-path analysis

Regional and subregional ground-water-flow models were coupled, and the output was analyzed by a particle-tracking method. The results were then used to assess the effects of ground-water withdrawals on the flow of saltwater in the Atlantic City 800-foot sand in Cape May County, New Jersey, and to estimate the travel time from areas in which the chloride concentration of the ground water exceeds 250 milligrams per liter to the county's nearest public supply wells. First, a quasi-three-dimensional finite-difference computer model of freshwater and saltwater flow that simulated regional ground-water flow through the unconsolidated materials underlying the New Jersey Coastal Plain was used to estimate flow at the boundaries of the subregional study area. The results of the regional simulation were used as input to a second quasi-three-dimensional finite-difference model that was used to simulate flow in the subregion, the Atlantic City 800-foot sand in Cape May County. The results of the simulation of flow in the subregion were analyzed by a semianalytical particle-tracking method to estimate ground-water flow paths and travel time of ground water from areas in which chloride concentrations exceed 250 milligrams per liter to public supply wells located at Stone Harbor, New Jersey. Ground-water withdrawals from the Atlantic City 800-foot sand were assumed to be equal to those reported for 1991. Results of the analysis indicate that the time required for saltwater to reach the public supply wells is on the order of hundreds of years. These results, however, are based on the assumptions that the aquifer is homogeneous. The presence of zones of high permeability in the aquifer could reduce the predicted travel times of the saltwater from its present location to the supply wells. Travel times also could be reduced if ground-water withdrawals increase.

New Jersey↗

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

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 ground-water withdrawal from the Frenchy wells regularly exceeded total estimated ground-water recharge from Dog and Deadman Canyons. Water-quality samples were collected from selected Douglas, San Andres, and Boles public-supply wells from December 1994 to February 1995. Concentrations of dissolved nitrate show the most consistent increases between current and historical data. Current concentrations of dissolved nitrate are greater than historical concentrations in 7 of 10 wells.

Water-Resources Investigations Report↗

Water-use analysis program for the Neshaminy Creek basin, Bucks and Montgomery counties, Pennsylvania

A water-use analysis computer program was developed for the Neshaminy Creek Basin to assist in managing and allocating water resources in the basin. The program was developed for IBM-compatible personal computers. Basin analysis and the methodologies developed for the Neshaminy Creek Basin can be transferred to other watersheds. The development and structure of the water-use analysis program is documented in this report. The report also serves as a user's guide. The program uses common relational database-management software that allows for water use-data input, editing, updating and output and can be used to generate a watershed water-use analysis report. The watershed-analysis report lists summations of public-supply well withdrawals; a combination of industrial, commercial, institutional, and ground-water irrigation well withdrawals; spray irrigation systems; a combination of public, industrial, and private surface-water withdrawals; wastewater-tratement-facility dishcarges; estimates of aggregate domestic ground-water withdrawals on an areal basin or subbasin basis; imports and exports of wastewater across basin or subbasin divides; imports and exports of public water supplies across basin or subbasin divides; estimates of evaporative loss and consumptive loss from produce incorporation; industrial septic-system discharges to ground water; and ground-water well-permit allocations.

Pennsylvania↗

Water withdrawal and use in Maryland, 1992-93

During 1992, about 1,430 million gallons per day (Mgal/d) of freshwater was withdrawn from surface-water and ground-water sources in Maryland. Total freshwater withdrawals increased during 1993 to about 1,480 Mgal/d. Saline surface- water withdrawals for cooling condensers increased from about 5,350 Mgal/d during 1992 to 5,840 Mgal/d during 1993. During 1992-93, most freshwater withdrawals (about 1,180 Mgal/d during 1992 and 1,200 Mgal/d during 1993) were from surface-water sources. Nearly 70 percent of the fresh surface water was withdrawn in the Potomac River drainage basin. Most ground water (about 178 Mgal/d in 1992 and 194 Mgal/d in 1993) was withdrawn in the Upper Chesapeake drainage basin.The Potomac Group aquifers provided most of the ground water (about 61 Mgal/d during 1992 and 64 Mgal/d during 1993). Ten water-use categoriesrepresent the major demands on the surface-water and ground-water resources of the State: Public supply, domestic, commercial, industrial, mining, thermoelectric power, hydroelectric power, livestock, irrigation, and aquaculture. Largest withdrawals were for public supply (790 Mgal/d during 1992 and 812 Mgal/d during 1993), and the water was used by residences, commercial establishments, and industries. Baltimore City received the largest public-supply deliveries (about 126 Mgal/d during1992 and 129 Mgal/d during 1993). Freshwater withdrawals for self-supplied domestic, commercial, mining, aquaculture, and irrigation uses increased during the period, whereas withdrawals for industrial and thermoelectric power uses decreased.

Water-Resources Investigations Report↗

Hydrogeology and sources of recharge to the Buffalo and Wahpeton aquifers in the southern part of the Red River of the North drainage basin, west-central Minnesota and southeastern North Dakota

Declining hydraulic heads in the Buffalo and Wahpeton aquifers are of concern to the Minnesota Department of Natural Resources and local water managers because of limited groundwater resources in the southern part of the Red River of the North drainage basin. The U.S. Geological Survey, in cooperation with the Minnesota Department of Natural Resources and Moorhead Public Service, investigated the hydrogeology of and sources of recharge to the Buffalo and Wahpeton aquifers. The Buffalo aquifer is a complex, heterogeneous outwash deposit composed of medium to coarse sand and gravel. Part of the Buffalo aquifer is unconfined and part is confined. The direction of ground water flow in the Buffalo aquifer is from east to west. Water-level declines in observation wells near the Moorhead Public Service North Well Field extend beyond the eastern and western boundaries of the Buffalo aquifer. Transmissivity and storativity calculated from the drawdown part of an aquifer test ranged from 20,870 to 23,852 feet squared per day and from 3.0 x 10 -5 to 3.2 x 10 -2 , respectively. Transmissivity and hydraulic conductivity values of 29,090 and 28,450 feet squared per day and 272 and 266 feet per day were calculated from the recovery-phase data. Potential recharge from the Buffalo River and its tributaries to the Buffalo aquifer ranged from 5 to 14 cubic feet per second. Recharge from precipitation where the Buffalo aquifer is unconfined was about 1.49 x 10 5 cubic feet per day. Recharge per unit length of the Buffalo aquifer during an aquifer test near the Moorhead Public Service North Well Field ranged from 3.9 x 10 -4 to 2.0 x 10 -2 cubic feet per day. The Wahpeton Shallow Sand, the Wahpeton Sand Plain, and the Wahpeton Buried Valley aquifers comprise the Wahpeton aquifers in order of increasing depth. All the aquifers are composed of fine- to coarse-grained sand mixed with gravel. Confining units are interleaved with the Wahpeton aquifers. Ground-water-flow directions in the Wahpeton aquifers were changed by ground-water development. Before development, ground water flowed from the Wahpeton Buried Valley aquifer upward to the Wahpeton Sand Plain aquifer and the Wahpeton Shallow Sand aquifer. After development, ground water flowed from the Wahpeton Shallow Sand aquifer to the Wahpeton Sand Plain and the Wahpeton Buried Valley aquifers. The potential sources of recharge to the Wahpeton aquifers investigated were the Red River of the North, and adjacent hydro geologic units. The volume of ground water pumped from the Wahpeton aquifers provides an estimate of the upper limit for the volume of recharge to the aquifer. Based on pumpage from all of the Wapheton aquifers from 1990 to 1993, the upper limit is about 580 million gallons per year (2.4 x 10 5 cubic feet per day).

Minnesota, North Dakota↗

Water-quality assessment of the Las Vegas Valley area and the Carson and Truckee River basins, Nevada and California: Nutrients, pesticides, and suspended sediment, October 1969-April 1990

The U.S. Geological Survey National Water-Quality Assessment Program (NAWQA) is designed to provide long-term, consistent information on water quality that can be used to describe local, regional, and national conditions. The full-scale NAWQA Program, initiated in 1991, includes both study-unit and national synthesis activities. Study-unit investigations provide scientific data and interpretations that will be integrated by national synthesis studies to assess the quality of the Nation's water resources. The Nevada Basin and Range (NVBR) study unit is one of 60 proposed NAWQA study units in the United States. These riverbasin-scale areas were selected to represent large proportions of the Nation's water use and population served by public supplies, and the Nation's geographic diversity. The NVBR study unit includes the Las Vegas Valley area, approximately 1,640 mi in southern Nevada, and the Carson River Basin (3,970 mi 2 ) and Truckee River Basin (3,230 mi 2 ) in northwestern Nevada and northeastern California. The areas are typical of Basin and Range physiography. Snowfall in high mountains provides streamflow and ground-water recharge in adjacent basins. Unconsolidated basin-fill deposits commonly exceed 1,000 ft in thickness and are principal aquifers in the study unit. The study-unit climate varies from humid continental in the Sierra Nevada where the Carson and Truckee Rivers originate (annual precipitation exceeds 30 in.) to desert in terminal parts of the basins, including the Carson Desert and lower altitudes in Las Vegas Valley, where annual precipitation is less than 5 in. In 1990, Nevada had the greatest population growth rate and the fourth greatest percentage of population residing in urban areas in the Nation. More than 90 percent of Nevada's population (about 1,090,000 in 1990) resided in the study unit; the Las Vegas Valley area (about 710,000) was the most populous area. In 1990, water use in the study unit was about 1,117,000 acre-ft. Water use in the Las Vegas Valley area was about 317,000 acre-ft; 91 percent was for public supplies. Las Vegas Valley was 79 percent range land, but the 5 percent urban land use has significantly affected water resources. Water use in the Carson River Basin was 538,000 acre-ft in 1990. About 95 percent of the water was used for irrigation, although only 5 percent of the land was used for irrigated agriculture. Water use in the Truckee River Basin was 262,000 acre-ft in 1990. Public supply used about 36 percent of the water, although only 3 percent of the land was urban. Nutrients, pesticides, and suspended sediments are important water-quality issues in the study unit. Urban runoff and treated sewage effluent contribute these constituents to Las Vegas Wash and the Truckee River. Urban and agricultural activities in the Carson and Truckee River Basins are also sources of these constituents.

California, Nevada↗

Sediment accumulation and water volume in Loch Raven Reservoir, Baltimore County, Maryland

Baltimore City and its metropolitan area are supplied with water from three reservoirs, Liberty Reservoir, Prettyboy Reservoir, and Loch Raven Reservoir. Prettyboy and Loch Raven Reservoirs are located on the Gunpowder Falls (figure 1). The many uses of the reservoir system necessitate coordination and communication among resource managers. The 1996 Amendment to the Safe Drinking Water Act require States to complete source-water assessments for public drinking-water supplies. As part of an ongoing effort to provide safe drinking water and as a direct result of these laws, the City of Baltimore and the Maryland Department of the Environment (MDE), in cooperation with other State and local agencies, are studying the Gunpowder Falls Basin and its role as a source of water supply to the Baltimore area. As a part of this study, the U.S. Geological Survey (USGS), in cooperation with the Maryland Geological Survey (MGS), with funding provided by the City of Baltimore and MDE, is examining sediment accumulation in Loch Raven Reservoir. The Baltimore City Department of Public Works periodically determines the amount of water that can be stored in its reservoirs. To make this determination, field crews measure the water depth along predetermined transects or ranges. These transects provide consistent locations where water depth, or bathymetric, measurements can be made. Range surveys are repeated to provide a record of the change in storage capacity due to sediment accumulation over time. Previous bathymetric surveys of Loch Raven Reservoir were performed in 1943, 1961, 1972, and 1985. Errors in data-collection and analysis methods have been assessed and documented (Baltimore City Department of Public Works, 1989). Few comparisons can be made among survey results because of changing data-collection techniques and analysis methods.

Water-Resources Investigations Report↗

Geology and ground-water resources of the Rawlins area, Carbon County, Wyoming

The Rawlins area in west-central Carbon County, south-central Wyoming includes approximately 634 square miles of plains and valleys grading into relatively rugged uplifts. The climate is characterized by low precipitation, rapid evaporation, and a wide range of temperature. Railroading and ranching are the principal occupations in the area. The exposed rocks in the area range in age from Precambrian through Recent. The older formations are exposed in the uplifted parts, the oldest being exposed along the apex of the Rawlins uplift. The formations dip sharply away from the anticlines and other uplifts and occur in the subsurface throughout the remainder of the area. The Cambrian rocks (undifferentiated), Madison limestone, Tensleep sandstone, Sun dance formation, Cloverly formation, Frontier formation, and Miocene and Pliocene rocks (undifferentiated) yield water to domestic and stock wells in the area. In the vicinity of the Rawlins uplift, the rocks of Cambrian age, Madison limestone, and Tensleep sandstone yield water to a few public-supply wells. The Cloverly formation yields water to public-supply wells in the Miller Hill and Sage Creek basin area. Wells that tap the Madison limestone, Tensleep sandstone, and Cloverly formation yield water under sufficient artesian pressure to flow at the land surface. The Browns Park formation yields water to springs that supply most of the Rawlins city water and supply water for domestic and stock use. Included on the geologic map are location of wells and test wells, depths to water below land surface, and location of springs. Depths to water range from zero in the unconsolidated deposits along the valley of Sugar Creek at the southern end of the Rawlins uplift to as much as 129 feet below the land surface in the Tertiary sedimentary rocks along the Continental Divide in the southern part of the area. The aquifers are recharged principally by precipitation that falls upon the area, by percolation from streams and ponds, and by movement of ground water from adjacent areas. Water is discharged from the ground-water reservoir by evaporation and transpiration, by seeps and springs, through wells, and by underflow out of the area. Although most water supplies in the area are obtained from springs, some domestic, stock, and public supplies are obtained from drilled wells, many yielding water under artesian pressure, and some flowing. Dissolved solids in the water from several geologic sources, ranging from 181 to 6,660 parts per million (ppm), indicate the varied chemical quality of ground water in the Rawlins area. Water from the Cambrian rocks, Tensleep sandstone, Cloverly formation, Frontier formation, Browns Park formation, and Miocene and Pliocene rocks is generally suitable for domestic and stock use. However, water yielded to the only well sampled in the lower part of the Frontier formation contained a high concentration of fluoride. Water from the rocks mentioned above contains less than 1,000 ppm of dissolved solids but in some places may contain iron in troublesome amounts. Water from the Madison limestone and Tensleep sandstone combined, Permian rocks, and Sundance formation contains more than 1,000 ppm of dissolved solids. Water in the Sundance, Cloverly, and Frontier :formations is very soft. More ground water can be obtained in the Rawlins area than is now being used. Many springs are undeveloped, and water can be obtained from additional wells without unduly lowering ground-water levels.

Water Supply Paper↗

Preliminary list of deep borings in the United States

The first preliminary list of deep borings in the United States was issued as Water-Supply Papers Nos. 57 and 61. The present publication includes all of the wells listed in these two papers, together with many additional borings, mostly of recent date. Messrs. M. L. Fuller and A. C. Veatch, of the eastern section of hydrology, and other geologists of the Survey have contributed many new data. Descriptions of borings published in reports issued since 1901 have been incorporated as far as practicable. All the entries are by counties. The wells and borings reported in the paper are all more than 400 feet in depth. The information concerning them has been obtained partly from replies to circular letters sent to all parts of the United States and partly from geological reports and other published sources. Owing to the difficulty of obtaining replies to the circulars, to lack of knowledge on the part of correspondents, and to the incompleteness of published records, doubtless there are borings which have not been reported. In regions of oil and gas wells, where borings are numerous, the individual wells can not be listed here, but representative wells are given. References to logs or records of the wells or extended descriptions of them are given in footnotes, and after the list of wells in each State there is added a list of the principal publications relating to deep borings in that State. The bearing of the information given in the columns of the lists probably is apparent unless, perhaps, in the one headed "Height to which the water rises." In this column an entry such as "-45" indicates that the water rises to within 45 feet of the surface; "+45" indicates that it is a flowing well and has sufficient head to raise the water 45 feet above the surface in an open pipe 45 feet or more in height. The yield in gallons per minute usually is estimated. Depths and diameters often have been reported from memory and different sources of publication sometimes give different figures. Most wells which are not stated to be "for oil," "for gas," "brine," "abandoned," etc., in the remarks column, or "not any" in the yield column, generally afford more or less water. Many of the gas and oil wells, active or abandoned, yield salt water.

Water Supply Paper↗

Hydrogeology of northwestern Nassau and northeastern Queens Counties, Long Island, New York

A detailed investigation of the geology and ground-water occurrence in northwestern Nassau and northeastern Queens Counties, N.Y., has been completed by the U.S. Geological Survey, in cooperation with the Nassau County Department of Public Works and the New York State Water Resources Commission. The area, about 63 square miles, includes the peninsulas of Great Neck and Manhasset Neck and the western part of Nassau County as far south as Garden City. Unconsolidated sediments of Pleistocene and Cretaceous aged 200 to 800 feet thick, constitute the ground-water reservoir of the area. The reservoir includes three discrete aquifers, not all found in the same locality, which transect geologic boundaries. The shallow unconfined aquifer consists of those permeable Pleistocene and Cretaceous deposits that lie within the upper part of the zone of saturation, which extends from slightly below sea level to more than 110 feet above sea level. It is an abundant source of water in much of the area, particularly in the southern part, where the aquifer consists of coarse sand and gravel in a glacial-outwash plain. The intermediate or principal aquifer consists largely of that part of the Magothy(?) formation that occurs from about 50 feet below sea level downward to the top of the clay member of the Raritan formation. Locally, however, the aquifer includes Pleistocene deposits which blanket the Magothy(?) formation or lie in channels cut into it. Although the principal aquifer has limited extent to the north, it is the chief source of water in most of the area, except the peninsulas. The lower or deep confined aquifer is found beneath the entire project area, and consists of the Lloyd sand member of the Raritan formation and the hydraulically contiguous Jameco gravel. The lower limit of the aquifer is the bedrock surface; its upper limit is defined by the overlying clay member of the Raritan formation and the Gardiners clay, the latter abutting against the clay member on the north or, in some valleys and embankments, lying directly upon the clay member. Thus, hydraulic continuity exists between the Lloyd sand member of the Raritan formation (Cretaceous) and the Jameco gravel (Pleistocene) in the northern part of Manhasset and Great Necks. The two contiguous clay bodies overlying the aquifer, the clay member of the Raritan formation and the Gardiners clay, form an effective confining bed which probably extends beyond the shore lines of the project area. The deep confined aquifer is particularly important on Manhasset and Great Necks where locally it is the only source of water available for large public-supply or industrial needs. In general, ground-water supplies in sufficient quantity and of excellent quality can be obtained from the three aquifers underlying northwestern Nassau and northeastern Queens Counties, N.Y. Ground-water withdrawals for public supply have increased with population growth and expanded use from an average of about 10 millions of gallons per day in 1940 to 30 mgd in 1957. In addition, about 10 mgd are pumped for various industrial, institutional and private uses. Much of the water pumped by industry is returned to the ground by diffusion wells and recharge basins. However, an increasing amount of water is lost from the ground-water reservoir due to the expanding network of server systems discharging directly to the sea. In the Manhasset Neck and Great Neck areas, ground-water resources are approaching full development in terms of the total available supply, if such development has not been reached already (1959). The chief limiting factor to further expansion lies in the geometry of the aquifers and the reduced thickness of permeable saturated sediments. In the northern part of both peninsulas, the ground-water reservoir is only about 200 to 400 feet thick, and, locally, as much as 75 percent of the strata in the reservoir consists of rather impermeable silt and clay of the Raritan formation or the Gardiners clay. I

Water Supply Paper↗

Selected contributions to ground-water hydrology by C.V. Theis, and a review of his life and work

This publication highlights two previously unpublished papers by C.V. Theis; each is augmented with a discussion that explains why he wrote the paper, attempts to discern why he did not publish the paper, and amplifies the information with reference material not included by Theis. 'A Primer on Anisotropy' was written in the early 1970's to provide practicing hydrogeologists of the day with a method of analyzing ground-water problems involving anisotropic hydraulic-conductivity distribution without using tensor mathematics. The equations were developed for horizontal flow through dipping beds with differing conductivities parallel and perpendicular to the bedding and for flow through dipping beds having three different hydraulic conductivities, one perpendicular to the bedding and two others parallel to the bedding, at an angle to the strike of the beds. Although most colleagues who reviewed the primer in the early 1970's encouraged its publication enthusiastically, at least one suggested the addition of some examples in which the method would be demonstrated. Handwritten notes from Theis' files indicate that he may have worked on some examples and possibly other additions to the paper. The comments by Charles A. Appel include some examples of the primer's use and augment the presentation with references to relevant published papers, both those available to Theis but not cited by him, and subsequent publications. 'Aquifers, Ground-Water Bodies, and Hydrophers' was written in the early 1980's as an attempt to clarify the semantic and conceptual confusion in the use of the term aquifer, applied by some investigators to the saturated part of a permeable formation and by others to the entire permeable formation. The physical distinction between the aquifer and the ground-water body is emphasized, and the term hydropher is proposed to describe the saturated part of a permeable formation. Theis' interest in and familiarity with the French literature on ground water was the basis for a discussion of the French usage, which eschews the term aquifer. The analysis and critique of Theis' palzler explains the 1835 paper from which aquifer was reportedly derived, and provides further justification for the term hydropher. Theis' more important contributions to ground-water hydrology were outgrowths of his solutions to small local water problems based on field investigations. The biographical sketch, drawing extensively from a partial autobiography that Theis had dictated, reveals both the reasons for and the intellectual processes that led to his development of the nonequilibrium concept of ground-water hydraulics. The sketch also describes the background of the man, reviews his career, and portrays the admiration and respect he elicited from his colleagues and associates. The magnitude of Theis' contribution to the science of ground-water hydrology, to the appraisal of the water resources of New Mexico, and to the early research on ground disposal of radioactive wastes is evident from the bibliography of his writings, which includes 168 reports, many of them unpublished. The evolution of his thinking about the role of geologic inhomogeneities in mass transport, conceptualized but not quantified, was the major contribution of the latter part of his career.

Water Supply Paper↗

Developing a framework for evaluating tallgrass prairie reconstruction methods and management

The thousands of hectares of prairie reconstructed each year in the tallgrass prairie biome can provide a valuable resource for evaluation of seed mixes, planting methods, and post-planting management if methods used and resulting characteristics of the prairies are recorded and compiled in a publicly accessible database. The objective of this study was to evaluate the use of such data to understand the outcomes of reconstructions over a 10-year period at two U.S. Fish and Wildlife Service refuges. Variables included number of species planted, seed source (combine-harvest or combine-harvest plus hand-collected), fire history, and planting method and season. In 2015 we surveyed vegetation on 81 reconstructions and calculated proportion of planted species observed; introduced species richness; native species richness, evenness and diversity; and mean coefficient of conservatism. We conducted exploratory analyses to learn how implied communities based on seed mix compared with observed vegetation; which seeding or management variables were influential in the outcome of the reconstructions; and consistency of responses between the two refuges. Insights from this analysis include: 1) proportion of planted species observed in 2015 declined as planted richness increased, but lack of data on seeding rate per species limited conclusions about value of added species; 2) differing responses to seeding and management between the two refuges suggest the importance of geographic variability that could be addressed using a public database; and 3) variables such as fire history are difficult to quantify consistently and should be carefully evaluated in the context of a public data repository.

Ecological Restoration↗

Fighting misinformation in seismology: Expert opinion on earthquake facts vs fiction

Misinformation carries the potential for immense damage to public understanding of science and for evidence-based decision making at an individual and policy level. Our research explores the following questions within seismology: which claims can be considered misinformation, which are supported by a consensus, and which are still under scientific debate? Consensus and debate are important to quantify, because where levels of scientific consensus on an issue are high, communication of this fact may itself serve as a useful tool in combating misinformation. This is a challenge for earthquake science, where certain theories and facts in seismology are still being established. The present study collates a list of common public statements about earthquakes and provides–to the best of our knowledge–the first elicitation of the opinions of 164 earth scientists on the degree of verity of these statements. The results provide important insights for the state of knowledge in the field, helping identify those areas where consensus messaging may aid in the fight against earthquake related misinformation and areas where there is currently lack of consensus opinion. We highlight the necessity of using clear, accessible, jargon-free statements with specified parameters and precise wording when communicating with the public about earthquakes, as well as of transparency about the uncertainties around some issues in seismology.

Frontiers in Earth Science↗

Invasion of American bullfrogs along the Yellowstone River

The American bullfrog ( Lithobates catesbeianus ) is a globally distributed invasive species that was introduced to the Yellowstone River floodplain of Montana. Knowledge about floodplain habitat features that allow for bullfrog persistence and spread will help identify effective control strategies. We used field surveys in 2010, 2012 and 2013 to describe bullfrog spread in the Yellowstone River floodplain and the habitat features that are associated with bullfrog occupancy and colonization. Bullfrogs in our study area expanded from ~ 60 km in 2010 to 106 km in 2013, and are spreading to up- and downstream habitats. The number of breeding sites (i.e., presence of bullfrog eggs or larvae) increased from 12 sites in 2010 to 45 sites in 2013. We found that bullfrogs were associated with deeper waters, emergent vegetation and public-access sites, which are habitat features that characterize permanent waters and describe human-mediated introductions. Control strategies that reduce the hydroperiod of breeding sites may help to limit bullfrog persistence and spread, while an increase in public outreach and education may help prevent further bullfrog introductions at public-access sites.

Montana↗