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USGS2017

Home range, den selection and habitat use of Carolina northern flying squirrels (Glaucomys sabrinus coloratus)

Context: Understanding habitat selection is important for determining conservation and management strategies for endangered species. The Carolina northern flying squirrel (CNFS; Glaucomys sabrinus coloratus ) is an endangered subspecies found in the high-elevation montane forests of the southern Appalachians, USA. The primary use of nest boxes to monitor CNFS has provided biased information on habitat use for this subspecies, as nest boxes are typically placed in suitable denning habitat. Aims: We conducted a radio-telemetry study on CNFS to determine home range, den site selection and habitat use at multiple spatial scales. Methods: We radio-collared 21 CNFS in 2012 and 2014–15. We tracked squirrels to diurnal den sites and during night-time activity. Key results: The MCP (minimum convex polygon) home range at 95% for males was 5.2 ± 1.2 ha and for females was 4.0 ± 0.7. The BRB (biased random bridge) home range at 95% for males was 10.8 ± 3.8 ha and for females was 8.3 ± 2.1. Den site ( n = 81) selection occurred more frequently in montane conifer dominate forests (81.4%) vs northern hardwood forests or conifer–northern hardwood forests (9.9% and 8.7%, respectively). We assessed habitat selection using Euclidean distance-based analysis at the 2nd order and 3rd order scale. We found that squirrels were non-randomly selecting for habitat at both 2nd and 3rd order scales. Conclusions: At both spatial scales, CNFS preferentially selected for montane conifer forests more than expected based on availability on the landscape. Squirrels selected neither for nor against northern hardwood forests, regardless of availability on the landscape. Additionally, CNFS denned in montane conifer forests more than other habitat types. Implications: Our results highlight the importance of montane conifer to CNFS in the southern Appalachians. Management and restoration activities that increase the quality, connectivity and extent of this naturally rare forest type may be important for long-term conservation of this subspecies, especially with the impending threat of anthropogenic climate change.

Appalachian Mountains↗

USGS2025

Performance evaluation of natural and nature-based features for coastal protection and co-benefits

Built infrastructure, such as seawalls and levees, has long been used to reduce shoreline erosion and protect coastal properties from flood impacts. In contrast, natural and nature-based features (NNBF), including marshes, mangroves, oyster reefs, coral reefs, and seagrasses, offer not only coastal protection but also a range of valuable ecosystem services. There is no clear understanding of the capacity of either natural habitats or NNBF integrated with traditional engineered infrastructure to withstand extreme events, nor are there well-defined breakpoints at which these habitats fail to provide coastal protection. Evaluating existing NNBF strategies using a standardized set of metrics can help to assess their effectiveness to better inform design criteria. This review identifies a selection of NNBF projects with long-term monitoring programs and synthesizes the monitoring data to provide a literature-based performance assessment. It also explores the integration of NNBF with existing gray infrastructure to enhance overall effectiveness.

Annual Review of Marine Science↗

USGS2014

Geophysical logging of bedrock wells for geothermal gradient characterization in New Hampshire, 2013

The U.S. Geological Survey, in cooperation with the New Hampshire Geological Survey, measured the fluid temperature of groundwater and other geophysical properties in 10 bedrock wells in the State of New Hampshire in order to characterize geothermal gradients in bedrock. The wells selected for the study were deep (five ranging from 375 to 900 feet and five deeper than 900 feet) and 6 had low water yields, which correspond to low groundwater flow from fractures. This combination of depth and low water yield reduced the potential for flow-induced temperature changes that would mask the natural geothermal gradient in the bedrock. All the wells included in this study are privately owned, and permission to use the wells was obtained from landowners before geophysical logs were acquired for this study. National Institute of Standards and Technology thermistor readings were used to adjust the factory calibrated geophysical log data. A geometric correction to the gradient measurements was also necessary due to borehole deviation from vertical. Maximum groundwater temperatures at the bottom of the logs ranged from 11.2 to 15.4 degrees Celsius. Geothermal gradients were generally higher than those typically reported for other water wells in the United States. Some of the high gradients were associated with high natural gamma emissions. Groundwater flow was discernible in 4 of the 10 wells studied but only obscured the part of the geothermal gradient signal where groundwater actually flowed into, out of, or through the well. Temperature gradients varied by mapped bedrock type but can also vary by localized differences in mineralogy or rock type within the wells.

New Hampshire↗

USGS2006

Borehole geophysical logging and aquifer-isolation tests conducted in well MG-1693 at North Penn Area 5 Superfund Site near Colmar, Montgomery County, Pennsylvania

Borehole geophysical logging and aquifer-isolation (packer) tests were conducted in well MG-1693 (NP-87) at the North Penn Area 5 Superfund Site near Colmar, Montgomery County, Pa. Objectives of the study were to identify the depth and yield of water-bearing zones, occurrence of vertical borehole flow, and effects of pumping on water levels in nearby wells. Caliper, natural-gamma, single-point-resistance, fluidtemperature, fluid-resistivity, heatpulse-flowmeter, and borehole-video logs were collected. Vertical borehole-fluid movement direction and rate were measured under nonpumping conditions. The suite of logs was used to locate water-bearing fractures, determine zones of vertical borehole-fluid movement, and select depths to set packers. Aquifer-isolation tests were conducted to sample discrete intervals and to determine specific capacities of water-bearing zones and effects of pumping individual zones on water levels in two nearby monitor wells. Specific capacities of isolated zones during aquifer-isolation tests ranged from 0.03 to 3.09 (gal/min)/ft (gallons per minute per foot). Fractures identified by borehole geophysical methods as water-producing or water-receiving zones produced water when isolated and pumped. Water enters the borehole primarily through high-angle fractures at 416 to 435 ft bls (feet below land surface) and 129 to 136 ft bls. Water exits the borehole through a high-angle fracture at 104 to 107 ft bls, a broken casing joint at 82 ft bls, and sometimes as artesian flow through the top of the well. Thirteen intervals were selected for aquifer-isolation testing, using a straddle-packer assembly. The specific capacity of interval 1 was 2.09 (gal/min)/ft. The specific capacities of intervals 2, 3, and 4 were similar—0.27, 0.30, and 0.29 (gal/min)/ft, respectively. The specific capacities of intervals 5, 6, 7, 8, and 10 were similar—0.03, 0.04, 0.09, 0.09, and 0.04 (gal/min)/ft, respectively. Intervals 9, 11, and 12 each showed a strong hydraulic connection outside the borehole with intervals above and below the isolated interval. The specific capacities of intervals 9, 11, 12, and 13 were similar—2.12, 2.17, 3.09, and 3.08 (gal/min)/ft, respectively. The aquifer-isolation tests indicate that wells MG-1693 (NP-87) and MG-924 (NP-21) are connected primarily through the high-angle fracture from 416 to 435 ft bls. Pumping in either of these wells directly impacts the other well, allowing the pumped well to draw from water-bearing zones in the nonpumped well that are not present in or are not connected directly to the pumped well. The two boreholes act as a single, U-shaped well. The aquifer-isolation tests also show that the lower zones in well MG-1693 (NP-87) are a major source of hydraulic head in well MG-1661 (W-13) through the broken casing joint at 82 ft bls. Water moving upward from the lower intervals in well MG-1693 (NP-87) exits the borehole through the broken casing joint, moves upward outside the borehole, possibly around and (or) through a poor or damaged casing seal, and through the weathered zone above bedrock to well MG-1661 (W-13). Samples for volatile organic compounds (VOCs) were collected in nine isolated intervals. Six compounds were detected (1,1-dichloroethane, 1,1-dichloroethene, cis-1,2-dichloroethene, toluene, 1,1,1-trichloroethane, and trichloroethene (TCE)), and TCE was found in all nine isolated intervals. Intervals 4 (124-149 ft bls) and 6 (277-302 ft bls) had the highest total concentration of VOCs (6.66 and 6.2 micrograms per liter, respectively). Intervals 1 (68-93 ft bls) and 4 each had five compounds detected, which was the highest number of compounds detected. Interval 5 (252-277 ft bls) had the lowest total concentration of VOCs (0.08 microgram per liter) and the least number of VOCs detected (one). Detected compounds were not evenly distributed throughout the intervals. Contaminants were found in shallow, intermediate, and deep intervals and were associated with high-angle fractures and rough areas that showed no distinct fractures.

Pennsylvania↗

USGS2022

Genome resequencing clarifies phylogeny and reveals patterns of selection in the toxicogenomics model Pimephales promelas

Background The fathead minnow ( Pimephales promelas ) is a model species for toxicological research. A high-quality genome reference sequence is available, and genomic methods are increasingly used in toxicological studies of the species. However, phylogenetic relationships within the genus remain incompletely known and little population-genomic data are available for fathead minnow despite the potential effects of genetic background on toxicological responses. On the other hand, a wealth of extant samples is stored in museum collections that in principle allow fine-scale analysis of contemporary and historical genetic variation. Methods Here we use short-read shotgun resequencing to investigate sequence variation among and within Pimephales species. At the genus level, our objectives were to resolve phylogenetic relationships and identify genes with signatures of positive diversifying selection. At the species level, our objective was to evaluate the utility of archived-sample resequencing for detecting selective sweeps within fathead minnow, applied to a population introduced to the San Juan River of the southwestern United States sometime prior to 1950. Results We recovered well-supported but discordant phylogenetic topologies for nuclear and mitochondrial sequences that we hypothesize arose from mitochondrial transfer among species. The nuclear tree supported bluntnose minnow ( P. notatus ) as sister to fathead minnow, with the slim minnow ( P. tenellus ) and bullhead minnow ( P. vigilax ) more closely related to each other. Using multiple methods, we identified 11 genes that have diversified under positive selection within the genus. Within the San Juan River population, we identified selective-sweep regions overlapping several sets of related genes, including both genes that encode the giant sarcomere protein titin and the two genes encoding the MTORC1 complex, a key metabolic regulator. We also observed elevated polymorphism and reduced differentation among populations (F ST ) in genomic regions containing certain immune-gene clusters, similar to what has been reported in other taxa. Collectively, our data clarify evolutionary relationships and selective pressures within the genus and establish museum archives as a fruitful resource for characterizing genomic variation. We anticipate that large-scale resequencing will enable the detection of genetic variants associated with environmental toxicants such as heavy metals, high salinity, estrogens, and agrichemicals, which could be exploited as efficient biomarkers of exposure in natural populations.

PeerJ↗

USGS1959

Ground-water levels and related hydrologic data from selected observation wells in Nassau County, Long Island, New York

Nassau County has experienced a rapid growth in population and industry in the past 20 years that has resulted in increased development of its ground-water resources. The county is located in west-central Long Island and its boundaries enclose a land area of 274 square miles. The climate is relatively mild and precipitation averages 43 inches a year. The precipitation is the ultimate source of natural replenishment to the ground-water reservoir. Ground water is found in the pore spaces of unconsolidated sands, gravels, and clays which overlay a basement of crystalline bedrock.

New York↗

USGS1999

Selected nutrients and pesticides in streams of the eastern Iowa basins, 1970-95

Water-quality data from 17 surface-water monitoring sites were compiled for 1970 through 1995 and analyzed to determine historical waterquality conditions and possible trends in the Eastern Iowa Basins study unit as part of the U.S. Geological Survey's National Water-Quality Assessment Program. The Eastern Iowa Basins encompasses the Wapsipinicon, Cedar, Iowa, and Skunk River Basins and covers about 19,500 square miles. Seven of the monitoring sites were sampled by the Iowa Department of Natural Resources, three sites by the Minnesota Pollution Control Agency, three sites by the University of Iowa Institute for Hydraulic Research, and four sites by the U.S. Geological Survey. Water-quality analyses typically consisted of nitrate, ammonia, total nitrogen, and total phosphorus, with limited analyses available for organic nitrogen, dissolved phosphorus, dissolved orthophosphate, and water-soluble pesticides. Long-term historical nutrient and pesticide data were not available for the Wapsipinicon River Basin. Median concentrations for total nitrogen ranged from 4.6 to 9.4 milligrams per liter, and maximum concentrations of total nitrogen ranged from 4.6 to 31 milligrams per liter. The majority of nitrogen transported in surface waters of the Eastern Iowa Basins study unit is in the form of nitrate (nitrogen). Median concentrations of total phosphorus ranged from less than 0.10 to 0.66 milligram per liter, and maximum concentrations of total phosphorus ranged from less than 0.10 to 5.4 milligrams per liter. Nitrate varied seasonally. Median concentrations of nitrate were largest during the spring and the winter (6.0 to 7.0 milligrams per liter) compared to the summer and fall (2.0 to 4.0 milligrams per liter). Concentrations of nitrate greater than 10 milligrams per liter typically occurred during spring runoff. Median ammonia concentrations generally were highest during the winter (approximately 0.3-0.5 milligram per liter) compared to the spring and summer when ammonia concentrations were often close to the detection limit (0.01 milligram per liter). In general, the median concentrations of total phosphorus varied less than 0.1 milligram per liter between seasons. The statistical analysis of the nutrient data typically indicated a strong positive correlation of nitrate with streamflow. Total phosphorus concentrations with streamflow showed greater variability than nitrate, perhaps reflecting the greater potential of transport of phosphorus on sediment rather than in the dissolved phase as with nitrate. Ammonia and ammonia plus organic nitrogen showed no correlation with streamflow or a weak positive correlation. Seasonal variations and the relations of nutrients and pesticides to streamflow generally corresponded with nonpoint‑source loadings, although possible point sources for nutrients were indicated by the data at selected monitoring sites. Statistical trend tests for concentrations and loads were computed for nitrate, ammonia, and total phosphorus. Trend analysis indicated decreases for ammonia and total phosphorus concentrations at several sites and increases for nitrate concentrations at other sites in the study unit.

Iowa, Minnesota↗

USGS1994

High-resolution single-channel seismic reflection surveys of Orange Lake and other selected sites of north central Florida

The potential fluid exchange between lakes of north central Florida and the Floridan aquifer and the process by which exchange occurs is of critical concern to the St. Johns Water Management District. High-resolution seismic tools with relatively new digital technology were utilized in collecting geophysical data from Orange, Kingsley, Lowry and Magnolia Lakes, and the Drayton Island area of St. Johns River. The data collected shows the application of these techniques in understanding the formation of individual lakes, thus aiding in the management of these natural resources by identifying breaches or areas where the confining units are thin or absent between the water bodies and the Floridan aquifer. Orange Lake, the primary focus of the study, is a shallow flooded plain that was formed essentially as an erosional depression in the clayey Hawthorn formation. The primary karstic features identified in the lake were cover subsidence, cover collapse and buried sinkholes structures in various sizes and stages of development. Orange Lake was divided into three areas southeast, southwest, and north-central. Karst features within the southeast area of Orange Lake are mostly cover subsidence sinkholes and associated features. Many of the subsidence features found are grouped together to form larger composite sinkholes, some greater than 400 m in diameter. The size of these composite sinkholes and the number of buried subsidence sinkholes distinguish the southeast area from the others. The potential of lake waters leaking to the aquifer in the southeast area is probably controlled by the permeability of the cover sediments or by fractures that penetrate the lake floor. The lake bottom and subsurface of the north-central areas are relatively subsidence sinkholes that have no cover sediments overlying them, implying that the sinks have been actively subsiding with some seepage into the aquifer from the lake in this area due to the possible presence of the active subsidence and faulting. The largest and most important features in the lake are the collapse sinkholes found along the southwestern shore that provide conduits for exchange between the lake and subsurface aquifer. There are two basic differences between the southwest and other areas of the lake: (1) the features found towards the central part of the lake are smaller in scale (1to 10 m across) and tend to be singular structures compare to the southwest area where features combined to form larger sinkholes (>400 m), and; (2) the southwest area is the only site where collapse dolines were identified. These dolines are located along the southwestern shoreline adjacent to Heagy-Burry Park. The comparison of seismic profiles from the several other selected lake and river sites to the Orange Lake profiles showed that other study areas were constructed of one or two large subsidences or a combination of sinkholes to form one large sinkhole. Aside from the difference in scale the basic characteristics of the subsidence sinkholes were similar.

Open-File Report↗

USGS2003

Characterization of anthropogenic and natural sources of acid rock drainage at the Cinnamon Gulch abandoned mine land inventory site, Summit County, Colorado

Colorado's Cinnamon Gulch releases acid rock drainage (ARD) from anthropogenic and natural sources. In 2001, the total discharge from Cinnamon Gulch was measured at 1.02 cfs (29 L/s) at base flow and 4.3 cfs (122 L/s) at high flow (spring runoff). At base flow, natural sources account for 98% of the discharge from the watershed, and about 96% of the chemical loading. At high flow, natural sources contribute 96% of discharge and 92 to 95% of chemical loading. The pH is acidic throughout the Cinnamon Gulch watershed, ranging from 2.9 to 5.4. At baseflow, nearly all of the trace metals analyzed in the 18 samples exceeded state hardness-dependent water quality standards for aquatic life. Maximum dissolved concentrations of selected constituents included 16 mg/ L aluminum, 15 mg/L manganese, 40 mg/L iron, 2 mg/L copper, 560 ??g/L lead, 8.4 mg/L zinc, and 300 mg/L sulfate. Average dissolved concentrations of selected metals at baseflow were 5.5 mg/L aluminum, 5.5 mg/L manganese, 14 ??g/L cadmium, 260 ??g/L copper, 82 ??g/L lead, and 2.8 mg/L zinc.

Environmental Geology↗

USGS1977

Access routes to the United States Geological Survey's National Center, Reston, Virginia

The National Center: The U.S. Geological Survey, established in 1879 as a bureau in the Department of the Interior, is one of the Federal Government's major earth science research and fact-finding agencies. By 1960, the continued growth of the Survey's natural resources and environmental programs and activities led to the agency's headquarters personnel being housed in more than 30 different buildings scattered throughout the Washington, D.C. metropolitan area. In 1962, Congress approved the construction of a National Center to consolidate the overall Survey's headquarters effort. A site in Reston's industrial/educational complex was selected and on July 15, 1971, ground was broken for the John Wesley Powell Federal Building.

Report↗

USGS2022

Green infrastructure in the Great Lakes—Assessment of performance, barriers, and unintended consequences

The Great Lakes Basin covers around 536,393 square kilometers, and the Great Lakes hold more than 5,400 cubic miles of water, accounting for more than 20 percent of the world’s fresh surface water supply. The Great Lakes provide a source of drinking water to tens of millions of people in Canada and the United States and support one of the most diverse ecosystems in the world. Increasing urbanization combined with aging infrastructure and more extreme storm events because of changing weather patterns creates stormwater management challenges for communities across the Great Lakes region. A variety of green infrastructure (GI) practices, designed to decrease runoff and improve water quality, have been implemented throughout the region in response to these challenges; however, implementation often remains limited to local efforts and with little coordination among various levels of government because of, at least in part, a lack of clear standards for stormwater, limited funding, and a general uncertainty in the type and expected performance of these practices. City planners, engineers, and political leaders often see GI investment as riskier than other alternatives despite studies that determined, in most cases, practices can either reduce or not affect costs. This report summarizes selected published reports and data sources from studies done in Great Lakes states and compares the measured effects of various GI practices and their applicability in different settings around the Great Lakes. By summarizing selected published reports and data sources from studies done in Great Lakes states, this report provides foundational information for U.S. Geological Survey scientists and their local and national partners to assess the ability of GI to reduce stormwater runoff in Great Lakes urban areas. GI includes a variety of stormwater management techniques designed to mimic natural hydrologic processes like infiltration and evapotranspiration, which can decrease the volume of water running into sewers and streams. It can also improve water quality by trapping sediment, nutrients, and other contaminants. A variety of landscape practices can be incorporated into urban areas as GI, but the discussion here is limited to vegetated basins, vegetated channels, permeable pavement, urban tree canopy, and green roofs. Other types of GI, such as downspout disconnection, rainwater harvesting, and wet and dry detention basins were not included because hydrologic function and associated components are not widely monitored or evaluated in literature.

Illinois, Indiana, Michigan, Minnesota, New York, ↗

USGS1996

What affects water quality in the Upper Colorado River basin?

The Upper Colorado River Basin is 1 of 60 study units selected for water-quality assessment by the U.S. Geological Survey as part of the National Water-Quality Assessment program. Understanding the environmental setting of the Upper Colorado River Basin study unit is important in evaluating water-quality issues in the basin. Information about the environmental setting identifies the basin characteristics and includes natural and human factors that affect the physical, chemical, and biological quality of water in the basin. This information has been used to design surface-water- and ground-water-quality sampling networks in the basin to assess overall water quality of the basin

Colorado↗

USGS1987

Surface-water-quality assessment of the upper Illinois River basin in Illinois, Indiana, and Wisconsin; project description

In 1986, the U.S. Geological Survey began a National Water-Quality Assessment program to (1) provide nationally consistent descriptions of the current status of water quality for a large, diverse, and geographically distributed part of the Nation's surface- and ground-water resources; (2) define, where possible, trends in water quality; and (3) identify and describe the relations of both status and trends in water quality to natural factors and the history of land use and land- and waste-management activities. The program is presently in a pilot phase that will test and modify, as necessary, concepts and approaches in preparation for possible full implementation of the program in the future. The upper Illinois River basin is one of four basins selected to test the concepts and approaches of the surface-water-quality element of the national program. The basin drains 10,949 square miles of Illinois, Indiana, and Wisconsin. Three principal tributaries are the Kankakee and Des Plaines Rivers that join to form the Illinois River and the Fox River. Land use is predominantly agricultural; about 75 percent of the basin is cultivated primarily for production of corn and soybeans. About 13 percent of the basin is urban area, most of which is located in the Chicago metropolitan area. The population of the basin is about 7 million. About 6 million people live in the Des Plaines River basin. Many water-quality issues in the upper Illinois River basin are related to sediment, nutrients, potentially toxic inorganic and organic constituents, and to water-management practices. Occurrence of sediment and the chemical constituents in the rivers and lakes within the basin has the potential to adversely affect the water's suitability for aquatic life, recreation, or, through the consumption of fish, human health. The upper Illinois River basin project consists of five major activities. The first activity--analysis of existing information and preparation of a report that describes recent water-quality conditions and trends--is currently underway. The second activity--fixed-station water-quality sampling at eight stations--began in April 1987 and will last at least 3 years. Water-quality data collected at these stations will be used to determine the frequency of occurrence of constituent concentrations, their annual and seasonal loads, and time trends in concentrations for a selected number of constituents. The third activity will be synoptic water-quality studies. Each study will involve sampling many sites at specific flow conditions and for selected water-quality constituents. Information gained from these studies will supplement informa tion gained from fixed-station sampling. A synoptic study of streambed sediments is tentatively planned for the summer of 1987 to describe the occurrence and distribution of trace elements in the basin. The fourth activity will consist of one or more topical subbasin or river-reach studies. The purpose of such studies is to better define certain water-quality conditions in specific areas and gain an understanding of the processes affecting the observed conditions. The fifth activity is the preparation of reports that will describe results from each of the first four activities. Quality assurance and coordination are being provided at both the national and pilot-project levels. A technical quality-assurance plan that addresses all aspects of sample collection, analysis, and reporting is being prepared at the national level. This plan will be appended as needed at the pilot-project level. A National Coordinating Work Group that functions under the auspices of the Interagency Advisory Committee on Water Data and the Advisory Committee on Water Data for Public Use has been established at the national level. A local liaison committee consisting of representatives from Federal, State, and local agencies has been established to enhance communication and to ensure that the scientific information produced by the

Open-File Report↗

USGS2020

Assessment of soil and water resources in the Organ Mountains-Desert Peaks National Monument, New Mexico

The Organ Mountains-Desert Peaks National Monument (Monument) in southern New Mexico was established in 2014. Given anticipated future demands in the Monument for recreation, livestock grazing, and maintenance of rights-of-way (for example, pipelines and powerlines), the Bureau of Land Management (BLM) needs a better understanding of the current soil and water resources and how infrastructure improvements could affect these resources and the watershed. Specifically, the BLM is concerned with infiltration and erosion and their relations to existing or planned infrastructure, such as roads, campgrounds, location of livestock grazing, and rights-of-way. Alternatives to the current land-use conditions, land-management practices, and infrastructure will be assessed by BLM to best protect Monument resources. The U.S. Geological Survey, in cooperation with the BLM, conducted a study to assess the soil and water resources within the Monument to provide an inventory and compilation of natural-resource information needed by resource managers for the BLM’s land-use planning process for this new national monument. The overall objectives of this study were to (1) compile and interpret existing soil- and water-resource data for the Monument and (2) provide a basic assessment of the surface hydrological effects of selected alternatives to current land use and infrastructure. Data were compiled by using geographic information system software and evaluated for hydrologic and landscape properties that influence infiltration, runoff, and erosion. The effects of changing vegetation were simulated by using different scenarios in the Rangeland Hydrology and Erosion Model. Results of this model indicate areas where soil loss or runoff may occur.

New Mexico↗

USGS1979

Revision of the documentation for a model for calculating effects of liquid waste disposal in deep saline aquifers

The model developed under this contract is a modified version of the deep well disposal model developed by INTERCOMP Resource Development and Engineering, Inc., for the U.S. Geological Survey (A model for calculating effects of liquid waste disposal in deep saline aquifers). The model is a finite-difference numerical solution of the partial differential equations describing (1) single phase fluid flow in aquifer, (2) energy transport by convection and conduction, and (3) contaminant transport dissolved in the fluid by convection and dispersion. Both the energy and the contaminant transports include molecular diffusion and hydrodynamic dispersion. The objective of the contract was to modify the original version of the model for more general applications. Some of the major features are as follows: (1) Fluid density is permitted to be a function of fluid pressure, temperature and contaminant concentration, the viscosity can be described as a function of pressure and temperature. (2) Aquifer heterogeneities in the hydrological properties can be described on a numerical grid block basis. (3) Free water surface is permitted to exist in the aquifer for shallow ground water applications. (4) Contaminant may absorb on rock surface or decay according to a first order reaction. The absorption is described by a linear adsorption isotherm function of rock type in the aquifer. (5) The model is extremely flexible in providing a wide choice of boundary conditions. These include natural flow in the aquifer, aquifer influence functions around the perimeter of the grid in recognition that the gridded region does not have no-flow boundaries, heat losses into the overlying impermeable strata, and the wellbore heat and pressure drop calculations coupled to the aquifer flow equations. (6) The model offers the option of selecting as iterative or direct solution technique, and selecting central or backward finite-difference approximations in both time and space. (7) Virtually any aquifer can be modeled by proper grid block description in three dimensions. In addition, the model is fully transient. The major limitation of the model arises using second-order correct (central-difference) finite-difference approximation in space. To avoid numerical oscillations in the solution, the user must restrict grid block and time step sizes depending upon the magnitude of the dispersivity.

Water-Resources Investigations Report↗

USGS1963

Geologic and hydrologic features of the San Bernardino area, California; with special reference to underflow across the San Jacinto fault

This is the second in a series of interpretive reports on subsurface outflow from the ground-water basins of San Bernardino County, Calif., prepared by the U.S. Geological Survey in cooperation with the San Bernardino County Flood Control District. One principal purpose of the study was to estimate the ground-water outflow from the Bunker Hill basin to the Rialto-Colton basin across the San Jacinto fault, which, except locally, forms a nearly impermeable boundary between the two basins. In addition, the report deals qualitatively with the geology, the fault barriers that divide the area into several ground-water basins, the physical nature and degree of imperviousness of the barriers, the occurrence and movement of ground water and fluctuations of water level in the basins, and the chemical quality of surface and ground waters in the San Bernardino area. The report includes a geologic map and sections, water-level-contour maps and profiles, and hydrographs of selected well. The Santa Ana River, the principal stream, flows generally westward across the area. Channels of the river and its tributaries overlie a large irregular structural depression filled with alluvial deposits ranging in age from late Tertiary to Recent and forming a valley bounded on the north by the San Gabriel Mountains, on the east by the San Bernardino Mountains, and on the south by an irregular group of hills. Large alluvial fans underlie most of the area, but its landforms also include alluvial benches and terraces near the mountains, stream channels, and elongate hills, ridges, and scarps along the trace of the San Jacinto fault, which strikes northwestward across the valley about in the center of the area. This fault and others divide the area into ground-water basins, which include the Bunker Hill, Rialto-Colton, upper and lower Lytle and Chino basins. The water-bearing deposits include the following units: the younger alluvium. of Recent age, which occupies principally the backfilled channels beneath the Santa Ana River and its tributaries and through which ground water moves from Bunker Hill basin to Rialto-Colton basin; the older alluvium, of Pleistocene age, which is the principal water-bearing unit of the area and yields water to more than a thousand wells; and continental deposits of Tertiary to Quaternary age, which crop out along the southern margin of the area and locally along the San Gabriel Mountains on the north. The younger alluvium attains a maximum thickness of about 125 feet beneath the Santa Ana River south of San Bernardino. Locally in the Bunker Hill basin it is composed of two members, an upper member of relatively impermeable clay and a lower member of highly permeable material in which water is confined by the upper member. The older alluvium locally has a known thickness greater than 700 feet; elsewhere in the San Bernardino Valley it may exceed 1,400 feet. Locally, where ground water is confined in Bunker Hill basin, the older alluvium is divided into three permeable water-bearing zones separated from each other and from the younger alluvium above by less permeable zones. In parts of Chino and Rialto-Colton basins the alluvium consists of a coarse-grained facies along a former course of a major stream that is interfingered with and overlain by relatively fine-grained deposits. The permeability of the younger alluvium in the area beneath the Santa Ana River downstream from the San Jacinto fault was determined from tests to be about 2,700 gallons per day per square foot. The permeability of the coarse water-yielding materials of the older alluvium several miles downstream was estimated from tests to be about the same magnitude. Rocks that yield practically no water include continental rocks of Tertiary age, which are not exposed in the area but are tapped by wells in Rialto-Colton basin, and crystalline and metamorphic rocks of pre-Tertiary age that form the bedrock of the area.

California↗

USGS2004

A cross-site comparison of methods used for hydrogeologic characterization of the Galena-Platteville aquifer in Illinois and Wisconsin, with examples from selected Superfund sites

The effectiveness of 28 methods used to characterize the fractured Galena-Platteville aquifer at eight sites in northern Illinois and Wisconsin is evaluated. Analysis of government databases, previous investigations, topographic maps, aerial photographs, and outcrops was essential to understanding the hydrogeology in the area to be investigated. The effectiveness of surface-geophysical methods depended on site geology. Lithologic logging provided essential information for site characterization. Cores were used for stratigraphy and geotechnical analysis. Natural-gamma logging helped identify the effect of lithology on the location of secondary- permeability features. Caliper logging identified large secondary-permeability features. Neutron logs identified trends in matrix porosity. Acoustic-televiewer logs identified numerous secondary-permeability features and their orientation. Borehole-camera logs also identified a number of secondary-permeability features. Borehole ground-penetrating radar identified lithologic and secondary-permeability features. However, the accuracy and completeness of this method is uncertain. Single-point-resistance, density, and normal resistivity logs were of limited use. Water-level and water-quality data identified flow directions and indicated the horizontal and vertical distribution of aquifer permeability and the depth of the permeable features. Temperature, spontaneous potential, and fluid-resistivity logging identified few secondary-permeability features at some sites and several features at others. Flowmeter logging was the most effective geophysical method for characterizing secondary-permeability features. Aquifer tests provided insight into the permeability distribution, identified hydraulically interconnected features, the presence of heterogeneity and anisotropy, and determined effective porosity. Aquifer heterogeneity prevented calculation of accurate hydraulic properties from some tests. Different methods, such as flowmeter logging and slug testing, occasionally produced different interpretations. Aquifer characterization improved with an increase in the number of data points, the period of data collection, and the number of methods used.

Scientific Investigations Report↗

USGS1969

Selected hydrologic data, southern Utah and Goshen Valleys, Utah

The purpose of this report is to present basic geologic, ground-water, surface-water, and quality of water data that are useful for the study and effective development of the water resources of southern Utah and Goshen Valleys. This report supplements an interpretive report which will be published later. Much of the basic data was collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, during the years 1935-67. Data collected by other organizations are also included in this report.

Utah↗