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Groundwater and surface-water resources near Red Fleet Reservoir, Uintah County, Utah

Red Fleet Reservoir in Uintah County, Utah, is an approximately 26,000 acre-foot (acre-ft) on-channel reservoir in the Big Brush Creek drainage on the south slopes of the Uinta Mountains. It is operated primarily for irrigation needs while providing a supplemental drinking-water supply to the Vernal, Utah area. Red Fleet Reservoir, which was operated by the Bureau of Reclamation and the Uintah Water Conservancy District through 2015, began storing water in May 1980. The reservoir is on southward dipping Mesozoic lithologies ranging from Jurassic to Cretaceous in age. The Nugget and Frontier Sandstone aquifers are the targeted units in this investigation, which is to characterize groundwater conditions that exist in each sandstone aquifer and how they interact with Red Fleet Reservoir. Groundwater levels were measured in six wells and one spring in the Nugget Sandstone and the Frontier Sandstone aquifers. Water levels in the Nugget Sandstone aquifer were 35–70 feet above the maximum stage of Red Fleet Reservoir on the west and east banks. Water levels in the Frontier Sandstone aquifer were 15–30 feet below the observed stage of Red Fleet Reservoir on the west bank during the study period. A water budget was calculated for Red Fleet Reservoir between May 1980 and December 2015. During this period, 1,050,000 acre-ft of water from Big Brush Creek discharged into the reservoir, while 993,000 acre-ft of water was released downstream of Red Fleet Dam. Total evaporation from May 1980 through December 2015 was about 52,000 acre-ft, while total precipitation over the same period was about 12,000 acre-ft. From May 1980 through December 2015, the total pumped volume of water from the Tyzack Pump Station, at the base of Red Fleet Dam, was about 42,000 acre-ft. Total groundwater discharge to Red Fleet Reservoir from 1980 through 2015 was about 40,000 acre-ft. Water was sampled from four wells and from the inflow arm of Red Fleet Reservoir, and analyzed for major-ion chemistry, select trace metals, nutrients, and environmental tracers. Water sampled from the Nugget Sandstone aquifer yielded good-quality water with dissolved-solids concentrations of less than 200 milligram per liter, and no trace elements above the Environmental Protection Agency drinking-water standards. Water sampled from the Frontier Sandstone aquifer yielded poor-quality water with dissolved-solids concentrations of about 2,150 milligrams per liter with trace elements approaching drinking-water standards for arsenic. Dissolved noble gases used to identify recharge elevations and temperatures for groundwater indicate that water in the Nugget Sandstone aquifer likely recharged at a high altitude and low temperature, and not locally because of interaction with Red Fleet Reservoir. The Frontier Sandstone aquifer is likely recharged at low elevation and at temperatures similar to those observed at Red Fleet Reservoir.

Utah↗

Assessment of stream conditions and trends in biological and water-chemistry data from selected streams in Chester County, Pennsylvania, 1981-97

Biological, chemical, and physical data were collected from a network of 43 sites in Chester County, Pa., from 1981 to 1997. The goal of the network is to assess stream conditions and determine trends in benthic-macroinvertebrate and water-chemistry data. Most sites in the network were assessed as nonimpacted or slightly impacted on the basis of biological metric analysis of benthic-macroinvertebrate data. Sites assessed as impacted were affected by habitat degradation, organic pollution, or toxins. Analysis of calculated biological metrics indicates that most sites were assessed as nonimpacted or slightly impacted between 1981 and 1997. Sites in the Pigeon, French, Pickering, and upper East Branch Brandywine Creek Basins generally were assessed as nonimpacted with stable physical and chemical data through the 17-year period. Sites in the Darby, Crum, Ridley, Valley, and lower East Branch Brandywine Creek Basins are being degraded from the reference conditions, primarily because of habitat alteration. The areas with the poorest stream quality were sites with greater than 50 percent agricultural land use, sites with greater than 10 percent impervious surface, and sites affected by wastewater-treatment plant discharges. These sites are being degraded by erosion, sedimentation, and nutrient enrichment. Trend analysis indicates that calculated biological metrics at most sites improved or remained unchanged between 1981 and 1997. Trend analysis on chemical constituents indicated that concentrations of nitrate and chloride were increasing, and concentrations of phosphorus and ammonia were unchanged or declining across Chester County from 1981 to 1997. The highest concentrations of ammonia and chloride were at locations affected by wastewater-treatment plant discharges. Concentrations of pesticides and other organic compounds in stream-bottom sediments decreased between 1983 and 1997 but these compounds still are present at low concentrations throughout Chester County.

Water-Resources Investigations Report↗

Water-chemistry data for selected springs, geysers, and streams in Yellowstone National Park, Wyoming, 1999-2000

Sixty-seven water analyses are reported for samples collected from 44 hot springs and their overflow drainages and two ambient-temperature acid streams in Yellowstone National Park (YNP) during 1990-2000. Thirty-seven analyses are reported for 1999, 18 for June of 2000, and 12 for September of 2000. These water samples were collected and analyzed as part of research investigations in YNP on microbially mediated sulfur oxidation in stream water, arsenic and sulfur redox speciation in hot springs, and chemical changes in overflow drainages that affect major ions, redox species, and trace elements. Most samples were collected from sources in the Norris Geyser Basin. Two ambient-temperature acidic stream systems, Alluvium and Columbine Creeks and their tributaries in Brimstone Basin, were studied in detail. Analyses were performed at or near the sampling site, in an on-site mobile laboratory truck, or later in a USGS laboratory, depending on stability of the constituent and whether or not it could be preserved effectively. Water temperature, specific conductance, pH, Eh, dissolved oxygen (D.O.), and dissolved H2S were determined on-site at the time of sampling. Alkalinity, acidity, and F were determined within a few days of sample collection by titration with acid, titration with base, and ion-selective electrode or ion chromatography (IC), respectively. Concentrations of S2O3 and SxO6 were determined as soon as possible (minutes to hours later) by IC. Concentrations of Br, Cl, NH4, NO2, NO3, SO4, Fe(II), and Fe(total) were determined within a few days of sample collection. Densities were determined later in the USGS laboratory. Concentrations of Li and K were determined by flame atomic absorption spectrometry. Concentrations of Al, As(total), B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe(total), K, Li, Mg, Mn, Na, Ni, Pb, Se, Si, Sr, V, and Zn were determined by inductively-coupled plasma-optical emission spectrometry. Trace concentrations of Cd, Cr, Cu, Pb, and Sb were determined by Zeeman-corrected graphitefurnace atomic-absorption spectrometry. Trace concentrations of As(total) and As(III) were determined by hydride generation atomic-absorption spectrometry using a flow-injection analysis system. Concentrations of Cl, NO3, Br, and SO4 were determined by IC. Concentrations of Fe(II) and Fe(total) were determined by the ferrozine colorimetric method. Concentrations of NO2 were determined by colorimetry using matrix-matched standards. Concentrations of NH4 were determined by IC, with reanalysis by colorimetry where separation of Na and NH4 peaks was poor. Dissolved organic carbon (DOC) concentrations were determined by the wet persulfate oxidation method.

Wyoming↗

Water-chemistry data for selected springs, geysers, and streams in Yellowstone National Park Wyoming, 2001-2002

Water analyses are reported for one-hundred-twenty-one samples collected from hot springs and their overflow drainages, the Gibbon River, and one ambient-temperature acid stream in Yellowstone National Park (YNP) during 2001-2002. Twenty-five analyses are reported for samples collected during May 2001, fifty analyses are reported for samples collected during September 2001, eleven analyses are reported for samples collected during October 2001, and thirty-five analyses are reported for samples collected during June and July 2002. Water samples were collected and analyzed for major and trace constituents from nine areas of YNP including Norris Geyser Basin, Nymph Lake and Roadside Springs, Lower Geyser Basin, Washburn Springs, Calcite Springs, Crater Hills, Mammoth Hot Springs, West Thumb Geyser Basin, and Brimstone Basin. These water samples were collected and analyzed as part of research investigations in YNP on arsenic redox distribution in hot springs and overflow drainages, the occurrence and distribution of dissolved mercury, and sulfur redox speciation. Most samples were analyzed for major cations and anions, trace metals, and iron, arsenic, nitrogen, and sulfur redox species. Only mercury concentration, pH, and specific conductance were determined for samples collected in October 2001 as they were collected during a reconnaissance field trip. Analyses were performed at the sampling site, in an onsite mobile laboratory, or later in a U.S. Geological Survey laboratory, depending on stability of the constituent and whether it could be preserved effectively. Water samples were filtered and preserved onsite. Water temperature, specific conductance, pH, Eh, and dissolved hydrogen sulfide were measured onsite at the time of sampling. Alkalinity and acidity were determined by titration, usually within a few days of sample collection. Concentrations of thiosulfate (S 2 O 3 ) and polythionate (S n O 6 ) were determined as soon as possible (generally minutes to hours after sample collection) by ion chromatography in an onsite mobile laboratory vehicle. Total dissolved iron and ferrous iron concentrations often were measured onsite in the mobile laboratory. Concentrations of aluminum, arsenic, barium, beryllium, boron, cadmium, calcium, chromium, cobalt, copper, iron, lead, lithium, magnesium, manganese, molybdenum, nickel, potassium, selenium, silica, sodium, strontium, vanadium, and zinc were determined by inductively coupled plasma-optical emission spectrometry. Trace concentrations of antimony, cadmium, chromium, cobalt, copper, lead, and selenium were determined by Zeeman-corrected graphite-furnace atomic-absorption spectrometry. Concentrations of total arsenic and arsenite were determined by hydride-generation atomic-absorption spectrometry using a flow-injection analysis system. Concentrations of total mercury were determined by cold-vapor atomic fluorescence spectrometry. Concentrations of bromide, chloride, nitrate, and sulfate were determined by ion chromatography. Concentrations of ferrous and total iron were determined by the FerroZine colorimetric method. Concentrations of nitrite were determined by colorimetry or chemiluminescence. Concentrations of ammonia were determined by ion chromatography, with reanalysis by colorimetry when separation of sodium and ammonia peaks was poor. Dissolved organic carbon concentrations were determined by the wet persulfate oxidation method.

Wyoming↗

Water-chemistry data for selected springs, geysers, and streams in Yellowstone National Park, Wyoming, 2003-2005

Water analyses are reported for 157 samples collected from numerous hot springs, their overflow drainages, and Lemonade Creek in Yellowstone National Park (YNP) during 2003–2005. Water samples were collected and analyzed for major and trace constituents from ten areas of YNP including Terrace and Beryl Springs in the Gibbon Canyon area, Norris Geyser Basin, the West Nymph Creek thermal area, the area near Nymph Lake, Hazle Lake, and Frying Pan Spring, Lower Geyser Basin, Washburn Hot Springs, Mammoth Hot Springs, Potts Hot Spring Basin, the Sulphur Caldron area, and Lemonade Creek near the Solfatara Trail. These water samples were collected and analyzed as part of research investigations in YNP on arsenic, antimony, and sulfur redox distribution in hot springs and overflow drainages, and the occurrence and distribution of dissolved mercury. Most samples were analyzed for major cations and anions, trace metals, redox species of antimony, arsenic, iron, nitrogen, and sulfur, and isotopes of hydrogen and oxygen. Analyses were performed at the sampling site, in an on-site mobile laboratory vehicle, or later in a U.S. Geological Survey laboratory, depending on stability of the constituent and whether it could be preserved effectively. Water samples were filtered and preserved onsite. Water temperature, specific conductance, pH, Eh (redox potential relative to the Standard Hydrogen Electrode), and dissolved hydrogen sulfide were measured onsite at the time of sampling. Acidity was determined by titration, usually within a few days of sample collection. Alkalinity was determined by titration within 1 to 2 weeks of sample collection. Concentrations of thiosulfate and polythionate were determined as soon as possible (generally minutes to hours after sample collection) by ion chromatography in an on-site mobile laboratory vehicle. Total dissolved-iron and ferrous-iron concentrations often were measured onsite in the mobile laboratory vehicle. Concentrations of dissolved aluminum, arsenic, boron, barium, beryllium, calcium, cadmium, cobalt, chromium, copper, iron, potassium, lithium, magnesium, manganese, molybdenum, sodium, nickel, lead, selenium, silica, strontium, vanadium, and zinc were determined by inductively-coupled plasma-optical emission spectrometry. Trace concentrations of dissolved antimony, cadmium, cobalt, chromium, copper, lead, and selenium were determined by Zeeman-corrected graphite-furnace atomic-absorption spectrometry. Dissolved concentrations of total arsenic, arsenite, total antimony, and antimonite were determined by hydride-generation atomic-absorption spectrometry using a flow-injection analysis system. Dissolved concentrations of total mercury and methyl mercury were determined by cold-vapor atomic-fluorescence spectrometry. Concentrations of dissolved chloride, fluoride, nitrate, bromide, and sulfate were determined by ion chromatography. Concentrations of dissolved ferrous and total iron were determined by the FerroZine colorimetric method. Concentrations of dissolved nitrite were determined by colorimetry or chemiluminescence. Concentrations of dissolved ammonium were determined by ion chromatography, with reanalysis by colorimetry when separation of sodium and ammonia peaks was poor. Dissolved organic carbon concentrations were determined by the wet persulfate oxidation method. Hydrogen and oxygen isotope ratios were determined using the hydrogen and CO 2 equilibration techniques, respectively.

Wyoming↗

Water-chemistry data for selected springs, geysers, and streams in Yellowstone National Park, Wyoming, 2006-2008

Water analyses are reported for 104 samples collected from numerous thermal and non-thermal features in Yellowstone National Park (YNP) during 2006-2008. Water samples were collected and analyzed for major and trace constituents from 10 areas of YNP including Apollinaris Spring and Nymphy Creek along the Norris-Mammoth corridor, Beryl Spring in Gibbon Canyon, Norris Geyser Basin, Lower Geyser Basin, Crater Hills, the Geyser Springs Group, Nez Perce Creek, Rabbit Creek, the Mud Volcano area, and Washburn Hot Springs. These water samples were collected and analyzed as part of research investigations in YNP on arsenic, antimony, iron, nitrogen, and sulfur redox species in hot springs and overflow drainages, and the occurrence and distribution of dissolved mercury. Most samples were analyzed for major cations and anions, trace metals, redox species of antimony, arsenic, iron, nitrogen, and sulfur, and isotopes of hydrogen and oxygen. Analyses were performed at the sampling site, in an on-site mobile laboratory vehicle, or later in a U.S. Geological Survey laboratory, depending on stability of the constituent and whether it could be preserved effectively. Water samples were filtered and preserved on-site. Water temperature, specific conductance, pH, emf (electromotive force or electrical potential), and dissolved hydrogen sulfide were measured on-site at the time of sampling. Dissolved hydrogen sulfide was measured a few to several hours after sample collection by ion-specific electrode on samples preserved on-site. Acidity was determined by titration, usually within a few days of sample collection. Alkalinity was determined by titration within 1 to 2 weeks of sample collection. Concentrations of thiosulfate and polythionate were determined as soon as possible (generally a few to several hours after sample collection) by ion chromatography in an on-site mobile laboratory vehicle. Total dissolved iron and ferrous iron concentrations often were measured on-site in the mobile laboratory vehicle. Concentrations of dissolved aluminum, arsenic, boron, barium, beryllium, calcium, cadmium, cobalt, chromium, copper, iron, potassium, lithium, magnesium, manganese, molybdenum, sodium, nickel, lead, selenium, silica, strontium, vanadium, and zinc were determined by inductively coupled plasma-optical emission spectrometry. Trace concentrations of dissolved antimony, cadmium, cobalt, chromium, copper, lead, and selenium were determined by Zeeman-corrected graphite-furnace atomic-absorption spectrometry. Dissolved concentrations of total arsenic, arsenite, total antimony, and antimonite were determined by hydride generation atomic-absorption spectrometry using a flow-injection analysis system. Dissolved concentrations of total mercury and methylmercury were determined by cold-vapor atomic fluorescence spectrometry. Concentrations of dissolved chloride, fluoride, nitrate, bromide, and sulfate were determined by ion chromatography. For many samples, concentrations of dissolved fluoride also were determined by ion-specific electrode. Concentrations of dissolved ferrous and total iron were determined by the FerroZine colorimetric method. Concentrations of dissolved ammonium were determined by ion chromatography, with reanalysis by colorimetry when separation of sodium and ammonia peaks was poor. Dissolved organic carbon concentrations were determined by the wet persulfate oxidation method. Hydrogen and oxygen isotope ratios were determined using the hydrogen and CO 2 equilibration techniques, respectively.

Wyoming↗

Precipitation-chemistry data at selected sites in northwestern Colorado, 1980-94

The chemical content of precipitation was monitored during the period 1980-94 at three sites at altitudes above 2,400 meters near the Piceance Basin in northwestern Colorado. Daily precipitation volumes, specific conductance, pH (in this report pH is expressed as hydrogen-ion concentration), concentrations of major cations and anions, calculated charge balance between cations and anions, and summary statistics of chemical concentrations are tabulated. Sampling sites are plotted on a map of the area. Seasonal variabilities of major cation and anion concentrations are presented graphically.

Open-File Report↗

Evaluation of ground-water and boron sources by use of boron stable-isotope ratios, tritium, and selected water-chemistry constituents near Beverly Shores, northwestern Indiana, 2004

Concentrations of boron greater than the U.S. Environmental Protection Agency (USEPA) 900 μg/L removal action level (RAL) standard were detected in water sampled by the USEPA in 2004 from three domestic wells near Beverly Shores, Indiana. The RAL regulates only human-affected concentrations of a constituent. A lack of well logs and screened depth information precluded identification of whether water from sampled wells, and their boron sources, were from human-affected or natural sources in the surficial aquifer, or associated with a previously defined natural, confined aquifer source of boron from the subtill or basal sand aquifers. A geochemically-based classification of the source of boron in ground water could potentially determine the similarity of boron to known sources or mixtures between known sources, or classify whether the relative age of the ground water predated the potential sources of contamination. The U.S. Geological Survey (USGS), in cooperation with the USEPA, investigated the use of a geochemical method that applied boron stable isotopes, and concentrations of boron, tritium, and other constituents to distinguish between natural and human-affected sources of boron in ground water and thereby determine if the RAL was applicable to the situation. Boron stable-isotope ratios and concentrations of boron in 17 ground-water samples and tritium concentrations in 9 ground-water samples collected in 2004 were used to identify geochemical differences between potential sources of boron in ground water near Beverly Shores, Indiana. Boron and δ 11 B analyses for this investigation were made on unacidified samples to assure consistency of the result with unacidified analyses of δ 11 B values from other investigations. Potential sources of boron included surficial-aquifer water affected by coal-combustion products (CCP) or domestic-wastewater, upward discharge of ground water from confined aquifers, and unaffected water from the surficial aquifer that was distant from human-affected boron sources. Boron concentrations in potential ground-water sources of boron were largest (15,700 to 24,400 μg/L) in samples of CCP-affected surficial aquifer water from four wells at a CCP landfill and smallest (27 to 63 μg/L) in three wells in the surficial aquifer that were distant from human-affected boron sources. Boron concentrations in water from the basal sand aquifer ranged from 656 μg/L to 1,800 μg/L. Boron concentrations in water from three domestic-wastewater-affected surficial aquifer wells ranged from 84 to 387 μg/L. Among the representative ground-water samples, boron concentrations from all four samples of CCP-affected surficial aquifer water and four of five samples of water from the basal sand aquifer had concentrations greater than the RAL. A comparison of boron concentrations in acid-preserved and unacidified samples indicated that boron concentrations reported for this investigation may be from about 11 to 16 percent less than would be reported in a standard analysis of an acidified sample. The stable isotope boron-11 was most enriched in comparison to boron-10 in ground water from a confined aquifer, the basal sand aquifer (δ 11 B, 24.6 to 34.0 per mil, five samples); it was most depleted in CCP-affected water from the surficial aquifer (δ 11 B, 0.1 to 6.6 per mil, four samples). Domestic-wastewater-affected water from the surficial aquifer (δ 11 B, 8.7 to 11.7 per mil, four samples) was enriched in boron-11, in comparison to individual samples of a borax detergent additive and a detergent with perborate bleach; it was intermediate in composition between basal sand aquifer water and CCP-affected water from the surficial aquifer. The similarity between a ground-water sample from the surficial aquifer and a hypothetical mixture of unaffected surficial aquifer and basal sand aquifer waters indicates the potential for long-term upward discharge of ground water into the surficial aquifer from one or more confined aquifers. Estimated δ 11 B values for acidified samples were depleted by 1.9 to 2.8 per mil in comparison to unacidified samples from the four wells sampled; those differences were small in comparison to the differences between δ 11 B values of representative sources of boron in ground water. Tritium concentrations ranged from 7.0 to 10.3 tritium units in six samples from the surficial aquifer and were less than 0.8 tritium units in three samples from the basal sand aquifer. Water from wells in the surficial aquifer represents predominantly modern, post-1972 recharge and sources of boron and other constituents. Water from the basal sand aquifer is associated with pre-1952 recharge from sources not affected by local boron inputs. Ground water from six wells (five domestic wells and one public-supply well) where the ground-water source was unknown had boron concentrations, boron isotope ratios, and tritium concentrations similar to water from the basal sand aquifer. Boron concentrations greater than the RAL were found in water from four of these six wells. The boron isotope and tritium data from these four wells indicate a natural source of boron in ground water; therefore, the RAL does not apply to boron concentrations in water from these wells. Water samples from two domestic wells where the ground-water source was unknown had boron concentrations less than the RAL and boron isotope ratios and tritium concentrations that were similar to domestic-wastewater-affected water from the surficial aquifer. The boron isotope ratio for a sample from one domestic well was similar to that of CCP-affected water from the surficial aquifer and detergent compositions; the boron concentration of that sample was less than the RAL. The classifications of differences among representative sources of boron in ground water and water samples from wells where the ground-water source was unknown generally agreed with distinctions based on strontium-87/strontium-86 ratios and concentrations of strontium, chloride, nitrate, and ammonia. This application of boron concentrations, boron isotope ratios, and tritium concentrations to classify differences in relation to potential sources of boron in ground water was able to distinguish between boron from natural sources and from human-affected sources that are subject to regulation.

Indiana↗

Major-ion and selected trace-metal chemistry of the Biscayne Aquifer, Southeast Florida

The major-ion and selected trace-metal chemistry of the Biscayne aquifer was characterized as part of the Florida Ground-Water Quality Monitoring Network Program, a multiagency cooperative effort concerned with delineating baseline water quality for major aquifer systems in the State. The Biscayne aquifer is unconfined and serves as the sole source of drinking water for more than 3 million people in southeast Florida. The Biscayne aquifer consists of highly permeable interbedded limestone and sandstone of Pleistocene and Pliocene age underlying most of Dade and Broward Counties and parts of Palm Beach and Monroe Counties. The high permeability is largely caused by extensive carbonate dissolution. Water sampled from 189 wells tapping the Biscayne aquifer was predominantly a calcium bicarbonate type with some mixed types occurring in coastal areas and near major canals. Major - ion is areally uniform throughout the aquifer. According to nonparametric statistical tests of major ions and dissolved solids, the concentrations of calcium, sodium, bicarbonate, and dissolved solids increased significantly with well depth ( 0.05 significance level ), probably a result of less circulation at depth. Potassium and nitrate concentrations decreased significantly with depth. Although the source of recharge to the aquifer varies seasonally, there was no statistical difference in the concentration of major ions in pared water samples from 27 shallow wells collected during wet and dry seasons. Median concentrations for barium, chromium, copper, lead, and manganese were below maximum or secondary maximum contaminant levels set by the US Environmental Protection Agency. The median iron concentration only slightly exceeded the secondary maximum contaminant level. The concentration of barium was significantly related (0.05 significance level) to calcium and bicarbonate concentration. No distinct areal pattern or vertical distribution of the selected trace metals was evident in water from the Biscayne aquifer. Sources for trace metals found in water from the Biscayne aquifer may include local contamination, well-construction techniques, canal - aquifer interactions, and natural occurrence in area soils and rock.

Florida↗

Ground-water quality data in the Central Eastside San Joaquin Basin 2006: Results from the California GAMA program

Ground-water quality in the approximately 1,695-square-mile Central Eastside study unit (CESJO) was investigated from March through June 2006 as part of the Statewide Basin Assessment Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Statewide Basin Assessment project was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the California State Water Resources Control Board (SWRCB) in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory (LLNL). The study was designed to provide a spatially unbiased assessment of raw ground-water quality within CESJO, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 78 wells in Merced and Stanislaus Counties. Fifty-eight of the 78 wells were selected using a randomized grid-based method to provide statistical representation of the study unit (grid wells). Twenty of the wells were selected to evaluate changes in water chemistry along selected lateral or vertical ground-water flow paths in the aquifer (flow-path wells). The ground-water samples were analyzed for a large number of synthetic organic constituents [volatile organic compounds (VOCs), gasoline oxygenates and their degradates, pesticides and pesticide degradates], constituents of special interest [perchlorate, N-nitrosodimethylamine (NDMA), and 1,2,3-trichloropropane (1,2,3-TCP)], inorganic constituents that can occur naturally [nutrients, major and minor ions, and trace elements], radioactive constituents, and microbial indicators. Naturally occurring isotopes [tritium, carbon-14, and uranium isotopes and stable isotopes of hydrogen, oxygen, nitrogen, sulfur, and carbon], and dissolved noble and other gases also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blanks, replicates, samples for matrix spikes) were collected for approximately one-sixth of the wells, and the results for these samples were used to evaluate the quality of the data for the ground-water samples. Assessment of the quality-control results showed that the environmental data were of good quality, with low bias and low variability, and resulted in censoring of less than 0.3 percent of the detections found in ground-water samples. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, and (or) blended with other waters to maintain acceptable water quality. Regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. However, to provide some context for the results, concentrations of constituents measured in the raw ground water were compared with health-based thresholds established by the U.S. Environmental Protection Agency (USEPA) and California Department of Public Health (CADPH) and thresholds established for aesthetic concerns (secondary maximum contaminant levels, SMCL-CA) by CADPH. VOCs and pesticides were detected in approximately half of the grid wells, and all detections in samples from CESJO wells were below health-based thresholds. All detections of nutrients and major elements in grid wells also were below health-based thresholds. Most detections of constituents of special interest, trace elements, and radioactive constituents in samples from grid wells were below health-based thresholds. Exceptions included two detections of arsenic that were above the USEPA maximum contaminant level (MCL-US), one detection of lead above the USEPA action level (AL-US), and one detection of vanadium and three detections of 1,2,3-TCP that were above the CADPH notification levels (NL-CA). All detections of radioactive constituents were below health-based thresholds, although fourteen samples had activities of radon-222 above the lower proposed MCL-US. Most of the samples from CESJO grid wells had concentrations of major elements, total dissolved solids, and trace elements below the non-enforceable thresholds set for aesthetic concerns. A few samples contained manganese or total dissolved solids at concentrations above the SMCL-CA thresholds.

California↗

Ground-water flow to Death Valley, as inferred from the chemistry and geohydrology of selected springs in Death Valley National Park, California and Nevada

Death Valley lies downgradient from adjacent valleys to the north, south, east, and west in California and Nevada, and is the site of substantial ground-water discharge. The sources of the discharging waters have been discussed by several investigators in the past and are of heightened concern because of the potential disposal of high-level radioactive waste at Yucca Mountain, Nevada, and because of ground-water withdrawals attendant to commercial mining in the northwestern Amargosa Valley region. This report describes high- and low-discharge springs in and along the Amargosa Range that were sampled to augment the level of understanding of the extent and distribution of westward ground-water flow through the range. The Black Mountains do not seem to be part of a significant path of ground-water flow from the Amargosa region. This is attributed to the complex lithology and geologic history of the Black Mountains structural block and to the presence of the intervening Furnace Creek fault zone. The only ground-water discharge associated with the Black Mountains where water chemistry reflects an external source or sources is Saratoga Spring, for which δ 2 H and δ 18 O data indicate recharge in the Spring Mountains to the east. The southern part of the Funeral Mountains transmits a large volume of water through faulted and fractured rocks of Cambrian age that lie at or along the distal part of the northeast -oriented Spotted Range-Mine Mountain structural zone. Waters discharging from springs in the Furnace Creek Ranch vicinity (Travertine and Nevares) both compositionally and isotopically resemble waters from the Ash Meadows spring group in the Amargosa Desert. The Ash Meadows springs and water in the Amargosa Valley alluvium likely are chemically representative of ground water entering the southern Funeral Mountains. Much less ground water flows through the central and northern Funeral Mountains than flows through the southern part, as indicated by the geologic setting and chemistry of Keane Wonder Spring. The northern one-half of the mountains comprises early-to-middle Proterozoic metamorphic rocks that are the core of the Funeral Mountains anticlinorium. The core is largely unfaulted, plunges to the northeast and southwest, and is truncated to some extent on the east by the shallow-dipping Boundary Canyon fault. This structural setting and the paucity of springs in the northern one-half of the Funeral Mountains indicate a long traveltime from the Amargosa region to the western margin of the northern and central parts of the mountains. The Grapevine Mountains include the highest elevations in the Amargosa Range. Substantial precipitation and recharge above about 2,000 meters are evinced by numerous small springs and seeps along the east and west margins. The local nature of the recharge is reflected in δ 2 H and δ 18 O values and in the spring chemistries that indicate control by Tertiary volcanic rocks. The highest spring discharges associated with the Grapevine Mountains are near the north end of the mountains in the Grapevine Ranch area. The springs in this area are similar chemically and isotopically, except for one or two order-of-magnitude differences in calcium, magnesium, and strontium concentrations and a 1.2 per mil difference in δ 13 C values. These differences can be attributed to differences in the distal parts of the respective flow paths. The springs also lie at the end of a northeast -oriented structural zone in the Walker Lane Belt, and their δ 2 H, δ 13 C, and δ 18 O values indicate a recharge area likely to the northeast, outside of the Grapevine Mountains.

California;Nevada↗

Comparison of select hematology and serum chemistry analtyes between wild-caught and aquarium-housed lake sturgeon ( Acipenser fulvescens )

Hematology and serum chemistry analytes were compared between wild-caught and aquarium-housed lake sturgeon ( Acipenser fulvescens ) to potentially improve understanding of medical issues in lake sturgeon. Blood samples were taken from 30 lake sturgeon exhibited in 11 institutions in the United States and from 23 experimentally stocked lake sturgeon caught in gill nets in the lower Genesee River in Rochester, New York, USA. For hematology, only segmented neutrophil count was significantly different, with wild-caught fish having a higher number of circulating neutrophils. For clinical chemistry analytes, chloride, uric acid, calcium, phosphate, glucose, aspartate aminotransferase, triglycerides, and creatine kinase were significantly different between the two cohorts. These differences are likely not clinically significant and are attributable to handling stress, variability in environmental parameters, or differences in nutritional status. This is the first report of hematology and serum chemistry values in aquarium-housed lake sturgeon and provides useful reference intervals for clinicians.

New York↗

Characterization of the hydrology, water chemistry, and aquatic communities of selected springs in the St. Johns River Water Management District, Florida, 2004

The hydrology, water chemistry, and aquatic communities of Silver Springs, De Leon Spring, Gemini Springs, and Green Spring in the St. Johns River Water Management District, Florida, were studied in 2004 to provide a better understanding of each spring and to compile data of potential use in future water-management decisions. Ground water that discharges from these and other north-central Florida springs originates from the Upper Floridan aquifer of the Floridan aquifer system, a karstic limestone aquifer that extends throughout most of the State's peninsula. This report summarizes data about flow, water chemistry, and aquatic communities, including benthic invertebrates, fishes, algae, and aquatic macrophytes collected by the U.S. Geological Survey, the St. Johns River Water Management District, and the Florida Department of Environmental Protection during 2004, as well as some previously collected data. Differences in water chemistry among these springs reflect local differences in water chemistry in the Upper Floridan aquifer. The three major springs sampled at the Silver Springs group (the Main Spring, Blue Grotto, and the Abyss) have similar proportions of cations and anions but vary in nitrate and dissolved oxygen concentrations. Water from Gemini Springs and Green Spring has higher proportions of sodium and chloride than the Silver Springs group. Water from De Leon Spring also has higher proportions of sodium and chloride than the Silver Springs group but lower proportions of calcium and bicarbonate. Nitrate concentrations have increased over the period of record at all of the springs except Green Spring. Compounds commonly found in wastewater were found in all the springs sampled. The most commonly detected compound was the insect repellant N,N'-diethyl-methyl-toluamide (DEET), which was found in all the springs sampled except De Leon Spring. The pesticide atrazine and its degradate 2-chloro-4-isopropylamino-6-amino-s-triazine (CIAT) were detected in water from the Silver Springs group and in both boils at Gemini Springs. No pesticides were detected in water samples from De Leon Spring and Green Spring. Evidence of denitrification was indicated by the presence of excess nitrogen gas in water samples from most of the springs. Aquatic communities varied among the springs. Large floating mats of cyanobacteria (blue-green algae), identified as Lyngbya wollei, were observed in De Leon Spring during all sampling events in 2004. At Gemini Springs, the dominant periphyton was Rhizoclonium sp. Of the three springs sampled for benthic invertebrates, De Leon Spring had the highest overall species richness and most disturbance intolerant species (Florida Index = 4). Green Spring had the lowest species richness of the springs sampled. Based on qualitative comparisons, overall macroinvertebrate species richness seemed to be negatively related to magnesium, potassium, sodium, and specific conductance. Invertebrate abundance was greatest when dissolved oxygen and nitrate were high but phosphorus and potassium concentrations were low. Dipteran abundance seemed to be positively associated with specific conductance and total organic carbon but negatively associated with nitrate-N. Amphipods were the numerically dominant group collected in most (six of nine) collections. Shifts in amphipod abundance of the two species collected (Gammarus sp. and Hyalella azteca) varied by season among the three springs, but there were no trends evident in the variation. Fish populations were relatively species-rich at the Silver Springs group, De Leon Spring, and Gemini Springs, but not at Green Spring. Nonindigenous fish species were observed at all springs except Green Spring.

Open-File Report↗

Spatial and temporal patterns in streamflow, water chemistry, and aquatic macroinvertebrates of selected streams in Fairfax County, Virginia, 2007–18

Urbanization substantially alters the landscape in ways that can impact stream hydrology, water chemistry, and the health of aquatic communities. Stormwater best management practices (BMPs) are the primary tools used to mitigate the effects of urban stressors such as increased runoff, decreased baseflow, and increased nutrient and sediment transport. To date, Fairfax County Virginia’s stormwater management program has made substantial investments into the implementation of both structural and nonstructural BMPs aimed at restoring and protecting watersheds. The U.S. Geological Survey (USGS), in cooperation with Fairfax County, Virginia, established a long-term water-resources monitoring program to evaluate the watershed-scale effects of these investments. Monitoring began at 14 stations in 2007 and was expanded to 20 stations in 2013. This report utilized the first 10 years of data collection to (1) assess water quantity and quality, as well as ecological condition; (2) compute annual nutrient and sediment loads; and (3) evaluate trends in streamflow, water quality, and ecological condition. Efforts are underway to link the biotic and abiotic patterns described herein to watershed management practices as well as factors such as land use change, public works infrastructure, and climate. Hydrologic, chemical, and benthic macroinvertebrate community conditions in the streams monitored were similar to those observed in other studies of urban streams. Multidecadal trends in baseflow indices and runoff ratios at long-term Chesapeake Bay Non-tidal Network streamgages (CB-NTN) indicate a decrease in groundwater recharge and increase in storm runoff as a result of urbanization. Streamflow yields varied spatially with land cover, geology, and soil characteristics, whereas flashiness was positively related to impervious area. Dissolved oxygen typically was lowest in the Coastal Plain and across all Triassic Lowlands streams, and highest in the Piedmont. Dissolved oxygen concentrations generally were above Virginia’s minimum criterion of 4.0 milligrams per liter (mg/L), most violations occurred at Paul Spring Branch in the Coastal Plain during the warmest months of the year owing to increased chemical and biological oxygen demand. Typical pH values of the monitored streams centered on neutrality (pH = 7); however, diurnal fluctuations were most prevalent in the continuous pH data at Flatlick Branch (FLAT; a Triassic Lowlands station), as a result of increased photosynthesis catalyzed by phosphorus-rich geology. Specific conductance (SC) varied spatially owing to geology (highest at Triassic Lowlands stations) and anthropogenic disturbance (watersheds with high impervious land cover). Specific conductance typically was inversely related to streamflow except in winter months following deicing road salt applications, when values increased by several orders of magnitude. A significant increase in SC of about 2 percent per year was observed from the combined trend result of all monitoring stations over the 10-year period. Significant SC increases occurred at nearly all monitoring stations. Increasing trends were observed during winter and nonwinter months, which suggests that salts applied to deice roadways and other impervious surfaces are stored in the environment and released year-round. Suspended-sediment (SS) concentrations in monthly samples did not vary significantly between most stations, but typically were highest in the spring and lowest in the fall as a result of seasonal differences in streamflow and climate. Suspended-sediment yields ranged from 62 to 1,428 tons per square mile (ton/mi 2 ), with a median of 302 ton/mi 2 . Annual loads were greatest during the wettest water years (October 1-September 30; 2008, 2011, and 2014), with the greatest interannual variability occurring at Difficult Run above Fox Lake (DIFF) and South Fork Little Difficult Run (SFLIL). Suspended sediment was primarily composed of silts and clays; however, the proportion of sand in suspended sediment was related positively to streamflow. Cross-correlation analyses suggested the dominant sources of SS were streambank erosion and resuspension of in-channel material at DIFF and FLAT; whereas, upland sources and erosion of upper streambanks were more common at Dead Run (DEAD), Long Branch (LONG), and SFLIL. Median total phosphorus (TP) concentrations ranged from 0.016 to 0.077 mg/L, with a networkwide median of 0.022 mg/L, were highest in the warm season (April-September), and were composed primarily of dissolved phosphorous. Although TP concentrations were relatively low across the network, the highest concentrations were consistently at stations located in the Triassic Lowlands, owing to phosphorous-rich geology, and in the Coastal Plain, owing to the low-phosphorous sorptive capacity of those soils. A significant increase in TP concentration occurred in a few stations, but the combined trend results from all stations demonstrated a significant increase of about 4 percent per year. Networkwide increases were also observed in total dissolved phosphorus, orthophosphate, and total particulate phosphorus. The composition of TP shifted from dissolved to particulate as streamflow increased and for this reason loads primarily were composed of particulate phosphorous. Median annual TP loads were highest at FLAT and DEAD and ranged from 247 to 642 pounds per square mile (lbs/mi 2 ) networkwide. Interannual variability in phosphorous yields was apparent at most stations; the highest loading years were also the wettest years during the study period and coincident with the highest peak annual flows. Total nitrogen (TN) concentrations typically were low throughout the network with exceptions occurring at stations located in watersheds with a high density of septic infrastructure. Elevated TN concentrations also were observed in some watersheds without a high density of septic systems and may be attributable to geologic and soil properties that limit denitrification as well as other unknown anthropogenic inputs. Total nitrogen typically was dominated by nitrate during baseflows; however, the proportion of particulate nitrogen increased during stormflows. Total nitrogen yields were similar across stations, with medians ranging from about 3,600 to 6,300 lbs/mi 2 and were related to annual streamflow volume. Total nitrogen concentrations and flow-normalized concentrations decreased over the 10-year period at 7 stations, with median reductions of about 2.5 percent. Increasing trends were observed at the two stations with the highest median TN concentration (Captain Hickory Run and SFLIL, 3–5 mg/L), both watersheds contain a high density of septic infrastructure. The combined trend results from all stations revealed no trend in TN and a declining trend in nitrate of about 2 percent per year. Overall, benthic community metrics indicated that streams throughout Fairfax County were initially of poor health; however, many metrics show an improving trend (from poor to fair based on the Fairfax County Index of Biological Integrity [IBI]). Significant increasing trends in IBI occurred at the network-scale and at 4 individual stations; additionally, scores improved by at least 1 qualitative category (for example, poor to fair, fair to good) at 11 of the 14 stations between 2009 (the first year all 14 stations were sampled) and 2017. Changes in all metrics suggest that the biodiversity, function, and condition of streams in Fairfax County are improving, but some of these improvements are driven by increased diversity and percent composition of organisms that are tolerant of the urban environment.

Virginia↗

Water-Quality Characteristics of Cottonwood Creek, Taggart Creek, Lake Creek, and Granite Creek, Grand Teton National Park, Wyoming, 2006

To address water-resource management objectives of the National Park Service in Grand Teton National Park, the U.S. Geological Survey in cooperation with the National Park Service has conducted water-quality sampling on streams in the Snake River headwaters area. A synoptic study of streams in the western part of the headwaters area was conducted during 2006. Sampling sites were located on Cottonwood Creek, Taggart Creek, Lake Creek, and Granite Creek. Sampling events in June, July, August, and October were selected to characterize different hydrologic conditions and different recreational-use periods. Stream samples were collected and analyzed for field measurements, major-ion chemistry, nutrients, selected trace elements, pesticides, and suspended sediment. Water types of Cottonwood Creek, Taggart Creek, Lake Creek, and Granite Creek were calcium bicarbonate. Dissolved-solids concentrations were dilute in Cottonwood Creek and Taggart Creek, which drain Precambrian-era rocks and materials derived from these rocks. Dissolved-solids concentrations ranged from 11 to 31 milligrams per liter for samples collected from Cottonwood Creek and Taggart Creek. Dissolved-solids concentrations ranged from 55 to 130 milligrams per liter for samples collected from Lake Creek and Granite Creek, which drain Precambrian-era rocks and Paleozoic-era rocks and materials derived from these rocks. Nutrient concentrations generally were small in samples collected from Cottonwood Creek, Taggart Creek, Lake Creek, and Granite Creek. Dissolved-nitrate concentrations were the largest in Taggart Creek. The Taggart Creek drainage basin has the largest percentage of barren land cover of the basins, and subsurface waters of talus slopes may contribute to dissolved-nitrate concentrations in Taggart Creek. Pesticide concentrations, trace-element concentrations, and suspended-sediment concentrations generally were less than laboratory reporting levels or were small for all samples. Water-quality characteristics of streams in the western part of the Snake River headwaters area were compared to water-quality characteristics of streams sampled in 2002 in the eastern part of the headwaters area. The median dissolved-solids concentration (55 milligrams per liter) for samples collected from western streams was smaller than the median dissolved-solids concentration (125 milligrams per liter) for samples collected from eastern streams. The small dissolved-solids concentrations in the western streams are a result of the large areas underlain by resistant Precambrian-era rocks that compose the Teton Range compared to the more erodable Mesozoic-era sedimentary rocks that compose the mountains in the eastern part of the headwaters area. The Teton Range also receives higher annual precipitation than the mountains in the east. The median total-nitrogen concentration (0.17 milligram per liter) in samples collected from streams in the western part of the Snake River headwaters area was larger than the median concentration (0.10 milligram per liter) for samples collected from streams in the eastern part of the headwaters area, in part because of larger dissolved-nitrate concentrations in samples from the western streams compared to the eastern streams. In contrast, total-phosphorus concentrations generally were larger for samples collected from eastern streams. Large total-phosphorus concentrations in the eastern streams were associated with large suspended-sediment concentrations. The source of the phosphorus and sediment probably is Mesozoic-era sedimentary rocks of marine origin that underlie parts of the eastern drainage basins.

Scientific Investigations Report↗

Using multiple chemical indicators to characterize and determine the age of groundwater from selected vents of the silver springs group, Central Florida, USA

The Silver Springs Group, Florida (USA), forms the headwaters of the Silver River and supports a diverse ecosystem. The 30 headwater springs divide into five subgroups based on chemistry. Five selected spring vents were sampled in 2007 to better understand the contaminant sources and groundwater flow system. Elevated nitrate-N concentrations (>0.8mg/L) in the five spring vents likely originate from inorganic (fertilizers) and organic sources, based on nitrogen and oxygen isotope ratios of nitrate. Evidence for denitrification in the Lost River Boil spring includes enriched ??15N and ??18O, excess N2 gas, and low dissolved O2 concentrations (<0.5mg/L). Multiple age-tracer data (SF6, 3H, tritiogenic 3He) for the two uppermost springs (Mammoth East and Mammoth West) indicate a binary mixture dominated by recent recharge water (mean age 6-7 years, and 87-97% young water). Tracer data for the three downstream spring vents (Lost River Boil, Catfish Hotel-1, and Catfish Conventional Hall-1) indicate exponential mixtures with mean ages of 26-35 years. Contamination from non-atmospheric sources of CFCs and SF5CF3 precluded their use as age tracers here. Variations in chemistry were consistent with mean groundwater age, as nitrate-N and dissolved O2 concentrations were higher in younger waters, and the Ca/Mg ratio decreased with increasing mean age. ?? 2010 Springer-Verlag (outside the USA).

Hydrogeology Journal↗