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USGS1996

Snow-depth and water-equivalent data for the Fairbanks area, Alaska, spring 1995

Snow depths at 34 sites and snow-water equivalents at 13 sites in the Fairbanks area were monitored during the 1995 snowmelt period (March 30 to April 26) in the spring of 1995. The U.S. Geological Survey conducted this study in cooperation with the Fairbanks International Airport, the University of Alaska Fairbanks, the Alaska Department of Natural Resources-Division of Mining and Water Management, the U.S Army, Alaska, and the U.S. Army Corps of Engineers-Alaska District. These data were collected to provide information about potential recharge of the ground-and surface-water systems during the snowmelt period in the Fairbanks area. This information is needed by companion geohydrologic studies of areas with known or suspected contaminants in the subsurface. Data-collection sites selected had open, boggy, wooded, or brushy vegetation cover and had different slope aspects. The deepest snow at any site, 27.1 inches, was recorded on April 1, 1995; the shallowest snow measured that day was 19.1 inches. The snow-water equivalents at these two sites were 5.9 inches and 4.5 inches, respectively. Snow depths and water equivalents were comparatively greater at open and bog sites than at wooded or brushy sites. Snow depths and water equivalents at all sites decreased throughout the measuring period. The decrease was more rapid at open and boggy sites than at wooded and brushy sites. Snow had completely disappeared from all sites by April 26, 1995.

Open-File Report↗

USGS1993

Application of a geographic information system in analyzing the occurrence of atrazine in groundwater of the mid-continental United States

The US Geological Survey, US Department of Agriculture, and US Environmental Protection Agency are conducting research and regional assessments in support of policy alternatives intended to protect water resources from agricultural chemical contamination. The mid-continent was selected because of the intense row crop agriculture and associated herbicide application in this region. An application of a geographic information system is demonstrated for analyzing and comparing the distribution of estimated atrazine use to the detection rate of atrazine in groundwater. Understanding the relations between atrazine use and detection in groundwater is important in policy deliberations to protect water resources. Relational analyses between measures of chemical use and detection rate by natural resource units may provide insight into critical factors controlling the processes that result in groundwater contamination from agricultural chemicals.

Conference Paper↗

USGS2012

Quantity and quality of stormwater collected from selected stormwater outfalls at industrial sites, Fort Gordon, Georgia, 2011

An assessment of the quantity and quality of stormwater runoff associated with industrial activities at Fort Gordon was conducted from January through December 2011. The assessment was provided to satisfy the requirements from a general permit that authorizes the discharge of stormwater under the National Pollutant Discharge Elimination System from a site associated with industrial activities. The stormwater quantity refers to the runoff discharge at the point and time of the runoff sampling. The study was conducted by the U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon. The initial scope of this study was to sample stormwater runoff from five stations at four industrial sites (two landfills and two heating and cooling sites). As a consequence of inadequate hydrologic conditions during 2011, no samples were collected at the two landfills; however, three samples were collected from the heating and cooling sites. The assessment included the collection of physical properties, such as water temperature, specific conductance, dissolved oxygen, and pH; the detection of suspended materials (total suspended solids, total fixed solids, total volatile solids), nutrients and organic compounds, and major and trace inorganic compounds (metals); and the detection of volatile and semivolatile organic compounds. Nutrients and organic compounds, major and trace inorganic compounds, and volatile and semivolatile organic compounds were detected above the laboratory reporting levels in all samples collected from the three stations. The detection of volatile and semivolatile organic compounds included anthracene, benzo[ a ]anthracene, benzo[ a ]pyrene, benzo[ ghi ]perylene, cis ,1, 2-dichloroethene, dimethyl phthalate, fluoranthene, naphthalene, pyrene, acenaphthylene (station SWR11-3), and di-n-butyl phthalate (station SWR11-4).

Georgia↗

USGS2013

Quantity and quality of stormwater collected from selected stormwater outfalls at industrial sites, Fort Gordon, Georgia, 2012

An assessment of the quantity and quality of stormwater runoff associated with industrial activities at Fort Gordon was conducted from January through August 2012. The assessment was provided to satisfy the requirements from a general permit that authorizes the discharge of stormwater under the National Pollutant Discharge Elimination System from a site associated with industrial activities. The stormwater quantity refers to the runoff discharge at the point and time of the runoff sampling. The study was conducted by the U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon. Stormwater runoff samples were collected from five stations at four industrial sites, including two landfills (SWR11–1 and SWR11–2) and three heating and cooling sites, SWR11–3, SWR11–4, and SWR11–5. The assessment included the collection of physical properties, such as dissolved oxygen and pH; the detection of suspended materials (total suspended solids, total fixed solids, and total volatile solids), nutrients and organic compounds, and major and trace inorganic compounds (metals); and for the three heating and cooling sites, the detection of volatile and semivolatile organic compounds. Landfill site SWR11–2 had the greatest total suspended solid concentration (214 milligrams per liter) of all sites and exceeded the daily maximum effluent limit for landfills. Heating and cooling site SWR11–3 had the greatest total suspended solid concentration (169 milligrams per liter), total fixed solids (101 milligrams per liter), and total volatile solids (68 milligrams per liter) when compared to the three heating and cooling sites. Total nitrogen and phosphorus concentrations were 1.02 and 0.09, and 1.74 and 0.21 milligrams per liter, respectively, at landfill sites SWR11–1 and SWR11–2. At heating and cooling sites, total nitrogen and phosphorus concentrations ranged from 0.53 to 1.08 milligrams per liter and 0.07 to 0.1 milligram per liter, respectively, with the highest concentrations measured at site SWR11–3. Additionally, oil and grease concentrations at all sites were compared to applicable benchmark standards; no sample concentrations exceeded these standards. The estimated dissolved concentrations of cadmium, lead, nickel, zinc, mercury, and silver, and the total recoverable concentrations of arsenic and selenium were compared to applicable benchmark levels and to acute and chronic effect aquatic-life criteria for further screening purposes. The estimated dissolved zinc concentration (105 micrograms per liter) at site SWR11–3 was the only constituent to exceed a benchmark standard (40 micrograms per liter). Estimated dissolved zinc concentrations at sites SWR11–4 and SWR11–5 exceeded acute and chronic effect aquatic-life criteria. Estimated dissolved concentrations of lead exceeded the chronic effect aquatic-life criteria at all sites and exceeded the acute effect criteria at site SWR11–3. Acute and chronic effect aquatic-life criteria for dissolved cadmium were exceeded at site SWR11–3. Samples from sites SWR11–3, SWR11–4, and SWR11–5 were analyzed for 83 volatile and semivolatile organic compounds. Eight polycyclic aromatic hydrocarbon compounds, benzo[ a ]pyrene, benzo[ b ]fluoranthene, benzo[ ghi ]perylene, benzo[ k ]fluoranthene, chrysene, indeno[1,2,3- cd ]pyrene, phenanthrene, and pyrene, were detected at all three sites. Of the 86 volatile and semivolatile organic compounds that were analyzed in stormwater samples from heating and cooling sites, 15 (18 percent) were detected at site SWR11–3, 12 (14 percent) were detected at site SWR11–4, and 17 (20 percent) were detected at site SWR11–5.

Georgia↗

USGS2011

Treating floodplain lakes of large rivers as study units for variables that vary within lakes; an evaluation using chlorophyll a and inorganic suspended solids data from floodplain lakes of the Upper Mississippi River

Contiguous floodplain lakes ('lakes') have historically been used as study units for comparative studies of limnological variables that vary within lakes. The hierarchical nature of these studies implies that study variables may be correlated within lakes and that covariate associations may differ not only among lakes but also by spatial scale. We evaluated the utility of treating lakes as study units for limnological variables that vary within lakes based on the criteria of important levels of among-lake variation in study variables and the observation of covariate associations that vary among lakes. These concerns were selected, respectively, to ensure that lake signatures were distinguishable from within-lake variation and that lake-scale effects on covariate associations might provide inferences not available by ignoring those effects. Study data represented chlorophyll a (CHL) and inorganic suspended solids (ISS) data from lakes within three reaches of the Upper Mississippi River. Sampling occurred in summer from 1993 through 2005 (except 2003); numbers of lakes per reach varied from 7 to 19, and median lake area varied from 53 to 101 ha. CHL and ISS levels were modelled linearly, with lake, year and lake x year effects treated as random. For all reaches, the proportions of variation in CHL and ISS attributable to differences among lakes (including lake and lake x year effects) were substantial (range: 18%-73%). Finally, among-lake variation in CHL and ISS was strongly associated with covariates and covariate effects that varied by lakes or lake-years (including with vegetation levels and, for CHL, log(ISS)). These findings demonstrate the utility of treating floodplain lakes as study units for the study of limnological variables and the importance of addressing hierarchy within study designs when making inferences from data collected within floodplain lakes.

Illinois;Iowa;Minnesota;Missouri;Wisconsin↗

USGS2005

Monitoring-well network and sampling design for ground-water quality, Wind River Indian Reservation, Wyoming

The Wind River Indian Reservation, located in parts of Fremont and Hot Springs Counties, Wyoming, has a total land area of more than 3,500 square miles. Ground water on the Wind River Indian Reservation is a valuable resource for Shoshone and Northern Arapahoe tribal members and others who live on the Reservation. There are many types of land uses on the Reservation that have the potential to affect the quality of ground-water resources. Urban areas, rural housing developments, agricultural lands, landfills, oil and natural gas fields, mining, and pipeline utility corridors all have the potential to affect ground-water quality. A cooperative study was developed between the U.S. Geological Survey and the Wind River Environmental Quality Commission to identify areas of the Reservation that have the highest potential for ground-water contamination and develop a comprehensive plan to monitor these areas. An arithmetic overlay model for the Wind River Indian Reservation was created using seven geographic information system data layers representing factors with varying potential to affect ground-water quality. The data layers used were: the National Land Cover Dataset, water well density, aquifer sensitivity, oil and natural gas fields and petroleum pipelines, sites with potential contaminant sources, sites that are known to have ground-water contamination, and National Pollutant Discharge Elimination System sites. A prioritization map for monitoring ground-water quality on the Reservation was created using the model. The prioritization map ranks the priority for monitoring ground-water quality in different areas of the Reservation as low, medium, or high. To help minimize bias in selecting sites for a monitoring well network, an automated stratified random site-selection approach was used to select 30 sites for ground-water quality monitoring within the high priority areas. In addition, the study also provided a sampling design for constituents to be monitored, sampling frequency, and a simple water-table level observation well network.

Scientific Investigations Report↗

USGS1998

Analysis of ground-water-quality data of the Upper Colorado River basin, water years 1972-92

As part of the U.S. Geological Survey's National Water-Quality Assessment program, an analysis of the existing ground-water-quality data in the Upper Colorado River Basin study unit is necessary to provide information on the historic water-quality conditions. Analysis of the historical data provides information on the availability or lack of data and water-quality issues. The information gathered from the historical data will be used in the design of ground-water-quality studies in the basin. This report includes an analysis of the ground-water data (well and spring data) available for the Upper Colorado River Basin study unit from water years 1972 to 1992 for major cations and anions, metals and selected trace elements, and nutrients. The data used in the analysis of the ground-water quality in the Upper Colorado River Basin study unit were predominantly from the U.S. Geological Survey National Water Information System and the Colorado Department of Public Health and Environment data bases. A total of 212 sites representing alluvial aquifers and 187 sites representing bedrock aquifers were used in the analysis. The available data were not ideal for conducting a comprehensive basinwide water-quality assessment because of lack of sufficient geographical coverage. Evaluation of the ground-water data in the Upper Colorado River Basin study unit was based on the regional environmental setting, which describes the natural and human factors that can affect the water quality. In this report, the ground-water-quality information is evaluated on the basis of aquifers or potential aquifers (alluvial, Green River Formation, Mesaverde Group, Mancos Shale, Dakota Sandstone, Morrison Formation, Entrada Sandstone, Leadville Limestone, and Precambrian) and land-use classifications for alluvial aquifers. Most of the ground-water-quality data in the study unit were for major cations and anions and dissolved-solids concentrations. The aquifer with the highest median concentrations of major ions was the Mancos Shale. The U.S. Environmental Protection Agency secondary maximum contaminant level of 500 milligrams per liter for dissolved solids in drinking water was exceeded in about 75 percent of the samples from the Mancos Shale aquifer. The guideline by the Food and Agriculture Organization of the United States for irrigation water of 2,000 milligrams per liter was also exceeded by the median concentration from the Mancos Shale aquifer. For sulfate, the U.S. Environmental Protection Agency proposed maximum contaminant level of 500 milligrams per liter for drinking water was exceeded by the median concentration for the Mancos Shale aquifer. A total of 66 percent of the sites in the Mancos Shale aquifer exceeded the proposed maximum contaminant level. Metal and selected trace-element data were available for some sites, but most of these data also were below the detection limit. The median concentrations for iron for the selected aquifers and land-use classifications were below the U.S. Environmental Protection Agency secondary maximum contaminant level of 300 micrograms per liter in drinking water. Median concentration of manganese for the Mancos Shale exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level of 50 micrograms per liter in drinking water. The highest selenium concentrations were in the alluvial aquifer and were associated with rangeland. However, about 22 percent of the selenium values from the Mancos Shale exceeded the U.S. Environmental Protection Agency maximum contaminant level of 50 micrograms per liter in drinking water. Few nutrient data were available for the study unit. The only nutrient species presented in this report were nitrate-plus-nitrite as nitrogen and orthophosphate. Median concentrations for nitrate-plus-nitrite as nitrogen were below the U.S. Environmental Protection Agency maximum contaminant level of 10 milligrams per liter in drinking water except for 0.02 percent of the sites in the alluvial aquifer and 0.03 percent of the sites in the Mancos Shale. Concentrations of orthophosphate did not vary significantly among aquifers or land-use classifications. Historic water-quality data from wells and springs helped to characterize the regional distribution of ground-water quality information in the Upper Colorado River Basin study unit. The historical ground-water data summarized in this report will be used in the design of a ground-water-quality network. Because ground-water-quality issues in the study unit are related to high dissolved solids, sulfate, selenium, and nutrients, this report discusses some of the important findings related to these issues.

Colorado↗

USGS2004

An Inventory of Aquatic Macroinvertebrates and Calculation of Selected Biotic Indices for the U.S. Army Atterbury Reserve Forces Training Area near Edinburgh, Indiana, September 2000 - August 2002

An investigation was conducted to establish an inventory of aquatic macroinvertebrates in the streams at the U.S. Army Atterbury Reserve Forces Training Area near Edinburgh, Indiana. The data used to develop this inventory were collected during two sampling efforts in September 2000 and July and August 2002. The inventory identified 173 distinct taxa within the study-area streams. Although no rare or endangered species were found, one identified species, Cordulegaster maculata Selys (a twin-spotted spiketail dragonfly), is recognized by the Indiana Department of Natural Resources as being rare enough to warrant special concern. Biotic indices (indicators of water-quality conditions) were calculated from the macroinvertebrate data. Ephemeroptera, Plecoptera, Trichoptera Richness Index values calculated for 23 samples collected from 16 sites ranged from 5 to 15, with more than 75 percent of the values falling within the range of 7 to 11. Hilsenhoff Biotic Index scores and Invertebrate Community Index scores calculated for samples collected at three sites indicate that water quality at these sites ranged from good to poor. The one site with a poor water-quality index score had a small drainage area. The small drainage area and dry conditions during the sampling period may have contributed to the poor scores calculated for this site.

Indiana↗

USGS2021

Assessing the uncertainties in climatic estimates based on vegetation assemblages: Examples from modern vegetation assemblages in the American Southwest

Assemblages of fossil plant remains have been widely used to reconstruct past climatic conditions, usually through the application of methods that involve either finding vegetation analogues on the modern landscape (and using the modern associated climatic values as the basis for an estimate) or using the modern climatic ranges of individual taxa in an assemblage to determine the range of a given climate variable that would allow these plant taxa to live together. Although these approaches are relatively straightforward, it is difficult to assess the uncertainties associated with each approach, particularly in regard to their application to plant macrofossil assemblages. To explore the uncertainty that may arise from inaccuracy and imprecision in climate reconstructions and from ecological considerations we used variants of both approaches to estimate climate from two data sets of modern vegetation assemblages from the southwestern United States: (1) 1752 gridded “virtual plant assemblages” based on plant range maps that provide uniform spatial coverage of the presence or absence of major woody plant taxa across the study area; and (2) 43 modern packrat ( Neotoma spp.) midden presence-absence assemblages that are similar to fossil midden assemblages. By comparing observed and estimated climate values, we evaluated the quality of the climate estimates, identified sources of uncertainty, and characterized the nature and magnitude of the effects of these uncertainties on the climate estimates. Uncertainties in estimating climate from vegetation assemblages arise because any given plant taxon (or assemblage) must have the resiliency to survive a range of climatic variability, and because of the strong intercorrelations among climatic variables in the modern climate data. Additional sources of uncertainty in climate estimates from plant assemblages include: (1) the modern climate and plant distribution data that are selected as the basis for estimation; (2) the particular quantitative approach that is used to estimate climate; (3) the sufficiency of the number of taxa in the analysis for providing an unbiased representation of the vegetation community as it existed for each time period in the analysis; and, (4) the location of the assemblage on the climatic and environmental gradients in the calibration data set for each climate variable under consideration. We conclude that vegetation assemblages can provide valid and reproducible estimates of climatic variables and that the primary trends and mapped patterns in the observed climate data can be reconstructed from such estimates. However, many factors may affect the quality of an estimate from a given plant assemblage, including aspects of data selection, data adequacy, methodologies, and the location of the assemblage site relative to gradients in the base climate data. It is particularly difficult to accurately estimate extreme values in the observed climate data, because estimated values from either end of an observed climate gradient necessarily “move toward the middle” of the gradient. In addition, the interval chosen to represent modern climate (here we used 1961 to 1990) may have a large impact on the size of the estimated difference between modern and past climate at a given site.

Arizona, California, Colorado, Nevada, New Mexico,↗

USGS2019

Nanoscale molecular fractionation of organic matter within unconventional petroleum source beds

Fractionation of petroleum during migration through sedimentary rock matrices has been observed across lengths of meters to kilometers. Selective adsorption of specific chemical moieties at mineral surfaces and/or the phase behavior of petroleum during pressure changes typically are invoked to explain this behavior. Such phenomena are of interest as they impact both the quality and recoverability of petroleum resources. Given the current emphasis on unconventional (continuous) resources, there is a need to understand petroleum fractionation occurring during expulsion and migration at the nanometer to micron scale, due to the fine-grained nature of petroliferous mudrocks. Here, organic matter compositional differences observed within kukersites (petroleum source beds containing acritarch Gloeocapsomorpha prisca) and the overlying carbonate reservoir layer from the Ordovician Stonewall Formation are explored using a suite of spectroscopic methods, primarily through atomic force microscopy based infrared spectroscopy (AFM-IR). AFM-IR is capable of providing spatial resolutions approaching 50 nm and allows for assessment of the molecular fingerprint of kukersite organic matter across transition zones from organic-rich ‘source’ layers into neighboring carbonate ‘reservoir’ layers ~150 μm away. Results indicate that organic matter composition begins to vary immediately following expulsion from source layers, with loss of carbonyl groups and a concomitant decrease in alkyl chain-length, as migration distance increases. These chemical transitions correlate with a decrease in fluorescence intensity, increase in solid bitumen reflectance, and increase in Raman aromaticity proxies (D-G band separation) in the organic matter. Our findings are consistent with the retention of polar compounds onto mineral grains during expulsion and migration, following primary cracking and bituminization of the Gloeocapsomorpha prisca kerogen.

Energy and Fuels↗

USGS1995

Seasonal cycles in streamwater quality on Catoctin Mountain, Maryland

In 1980, the U.S. Congress mandated the National Acid Precipitation Assessment Program (NAPAP) to study the effects of acidic precipitation (acid rain). In 1982, the U.S. Geological Survey (USGS) was selected to be the lead Federal agency under NAPAP to monitor the composition of precipitation and its effects on the environment. In 1982, the USGS began to monitor precipitation and streamwater on Catoctin Mountain in north-central Maryland (fig. 1); the effort has continued through the present. Beginning in 1990, funding for these data-collection and interpretation activities was supplemented by the Maryland Department of the Environment and the Maryland Department of Natural Re- sources. The collection and interpretation of long-term precipitation and streamwater-quality records, such as those at Catoctin Mountain, provide valuable information for management decisions. At the local level, the information can be used to identify periods when streamwater quality may pose a danger to aquatic resources, such as finfish; at the national level, the information can be used to assess the effectiveness of the Clean Air Act Amendments.

Maryland↗

USGS2011

Assessment of groundwater, soil-gas, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2010

The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the groundwater, soil gas, and soil for contaminants at the Vietnam Armor Training Facility (VATF) at Fort Gordon, from October 2009 to September 2010. The assessment included the detection of organic compounds in the groundwater and soil gas, and inorganic compounds in the soil. In addition, organic contaminant assessment included organic compounds classified as explosives and chemical agents in selected areas. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. Four passive samplers were deployed in groundwater wells at the VATF in Fort Gordon. Total petroleum hydrocarbons were detected above the method detection level at all four wells. The only other volatile organic compounds detected above their method detection level were undecane and pentadecane, which were detected in two of the four wells sampled. Soil-gas samplers were deployed at 72 locations in a grid pattern across the VATF. Total petroleum hydrocarbons were detected in 71 of the 72 samplers (one sampler was destroyed in the field and not analyzed) at levels above the method detection level, and the combined mass of benzene, toluene, ethylbenzene, and total xylene was detected above the detection level in 31 of the 71 samplers that were analyzed. Other volatile organic compounds detected above their respective method detection levels were naphthalene, 2-methyl-naphthalene, tridecane, 1,2,4-trimethylbenzene, and perchloroethene. Subsequent to the soil-gas survey, four areas determined to have elevated contaminant mass were selected and sampled for explosives and chemical agents. No detections of explosives or chemical agents above their respective method detection levels were found at any of the sampling locations. The same four locations that were sampled for explosives and chemical agents were selected for the collection of soil samples. A fifth location also was selected on the basis of the elevated contaminant mass of the soil-gas survey. No metals that exceeded the Regional Screening Levels for Industrial Soils as classified by the U.S. Environmental Protection Agency were detected at any of the five VATF locations. The soil samples also were compared to values from the ambient, uncontaminated (background) levels for soils in South Carolina, as classified by the South Carolina Department of Health and Environmental Control. Because South Carolina is adjacent to Georgia and the soils in the coastal plain are similar, these comparisons are valid. No similar values are available for Georgia to use for comparison purposes. The metals that were detected above the ambient background levels for South Carolina, as classified by the South Carolina Department of Health and Environmental Control, include aluminum, arsenic, barium, beryllium, calcium, chromium, copper, iron, lead, magnesium, manganese, nickel, potassium, sodium, and zinc.

Georgia↗

USGS2012

Assessment of groundwater, soil-gas, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2011

The U.S. Geological Survey, in cooperation with the U.S. Department of the Army Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon, Georgia, assessed the groundwater, soil gas, and soil for contaminants at the Vietnam Armor Training Facility (VATF) at Fort Gordon, from October 2009 to September 2011. The assessment included the detection of organic compounds in the groundwater and soil gas, and inorganic compounds in the soil. In addition, organic contaminant assessment included organic compounds classified as explosives and chemical agents in selected areas. The assessment was conducted to provide environmental contamination data to the U.S. Army at Fort Gordon pursuant to requirements of the Resource Conservation and Recovery Act Part B Hazardous Waste Permit process. This report is a revision of "Assessment of soil-gas, surface-water, and soil contamination at the Vietnam Armor Training Facility, Fort Gordon, Georgia, 2009-2010," Open-File Report 2011-1200, and supersedes that report to include results of additional samples collected in July 2011. Four passive samplers were deployed in groundwater wells at the VATF in Fort Gordon. Total petroleum hydrocarbons and benzene and octane were detected above the method detection level at all four wells. The only other volatile organic compounds detected above their method detection level were undecane and pentadecane, which were detected in two of the four wells. Soil-gas samplers were deployed at 72 locations in a grid pattern across the VATF on June 3, 2010, and then later retrieved on June 9, 2010. Total petroleum hydrocarbons were detected in 71 of the 72 samplers (one sampler was destroyed in the field and not analyzed) at levels above the method detection level, and the combined mass of benzene, toluene, ethylbenzene, and total xylene (BTEX) was detected above the detection level in 31 of the 71 samplers that were analyzed. Other volatile organic compounds detected above their respective method detection levels were naphthalene, 2-methyl-naphthalene, tridecane, 1,2,4-trimethylbenzene, and perchloroethylene. After the results of the 71 soil-gas samplers were received, 31 additional passive soil-gas samplers were deployed on July 14, 2011, and retrieved on July 18, 2011. These 31 samplers were deployed on a larger areal scale to better define the extent of the contamination. Total petroleum hydrocarbons were detected above their method detection level at all 31 samplers, whereas BTEX was detected above its method detection level at 17 of the 31 samplers. Other organic compounds detected above their method detection levels were naphthalene, 2-methyl-naphthalene, octane, undecane, tridecane, pentadecane, 1,2,4-trimethylbenzene, 1,3,5-trimethylbenzene, chloroform, and perchloroethylene. Subsequent to the 2010 soil-gas survey, four areas determined to have elevated contaminant mass were selected and sampled for explosives and chemical agents. No detections of explosives or chemical agents above their respective method detection levels were found at any of the sampling locations. The same four locations that were sampled for explosives and chemical agents were selected for the collection of soil samples. A fifth location also was selected on the basis of the elevated contaminant mass of the soil-gas survey. No metals that exceeded the Regional Screening Levels for Industrial Soils, as classified by the U.S. Environmental Protection Agency, were detected at any of the five VATF locations. The soil samples also were compared to values from the ambient, uncontaminated (background) levels for soils in South Carolina, as classified by the South Carolina Department of Health and Environmental Control. Because South Carolina is adjacent to Georgia and the soils in the Coastal Plain are similar, these comparisons are valid. No similar values are available for Georgia to use for comparison purposes. The metals that were detected above the ambient background levels for South Carolina, as classified by the South Carolina Department of Health and Environmental Control, include aluminum, arsenic, barium, beryllium, calcium, chromium, copper, iron, lead, magnesium, manganese, nickel, potassium, sodium, and zinc.

Georgia↗

USGS2007

Assessment of hydrology, water quality, and trace elements in selected placer-mined creeks in the birch creek watershed near central, Alaska, 2001-05

Executive Summary The U.S. Geological Survey, in cooperation with the Bureau of Land Management, completed an assessment of hydrology, water quality, and trace-element concentrations in streambed sediment of the upper Birch Creek watershed near Central, Alaska. The assessment covered one site on upper Birch Creek and paired sites, upstream and downstream from mined areas, on Frying Pan Creek and Harrison Creek. Stream-discharge and suspended-sediment concentration data collected at other selected mined and unmined sites helped characterize conditions in the upper Birch Creek watershed. The purpose of the project was to provide the Bureau of Land Management with baseline information to evaluate watershed water quality and plan reclamation efforts. Data collection began in September 2001 and ended in September 2005. There were substantial geomorphic disturbances in the stream channel and flood plain along several miles of Harrison Creek. Placer mining has physically altered the natural stream channel morphology and removed streamside vegetation. There has been little or no effort to re-contour waste rock piles. During high-flow events, the abandoned placer-mine areas on Harrison Creek will likely contribute large quantities of sediment downstream unless the mined areas are reclaimed. During 2004 and 2005, no substantial changes in nutrient or major-ion concentrations were detected in water samples collected upstream from mined areas compared with water samples collected downstream from mined areas on Frying Pan Creek and Harrison Creek that could not be attributed to natural variation. This also was true for dissolved oxygen, pH, and specific conductance-a measure of total dissolved solids. Sample sites downstream from mined areas on Harrison Creek and Frying Pan Creek had higher median suspended-sediment concentrations, by a few milligrams per liter, than respective upstream sites. However, it is difficult to attach much importance to the small downstream increase, less than 10 milligrams per liter, in median suspended-sediment concentration for either basin. During low-flow conditions in 2004 and 2005, previously mined areas investigated on Harrison Creek and on Frying Pan Creek did not contribute substantial suspended sediments to sample sites downstream from the mined areas. No substantial mining-related water- or sediment-quality problems were detected at any of the sites investigated in the upper Birch Creek watershed during low-flow conditions. Average annual streamflow and precipitation were near normal in 2002 and 2003. Drought conditions, extreme forest fire impact, and low annual streamflow set apart the 2004 and 2005 summer seasons. Daily mean streamflow for upper Birch Creek varied throughout the period of record-from maximums of about 1,000 cubic feet per second to minimums of about 20 cubic feet per second. Streamflow increased and decreased rapidly in response to rainfall and rapid snowmelt events because the steep slopes, thin soil cover, and permafrost areas in the watershed have little capacity to retain runoff. Median suspended-sediment concentrations for the 115 paired samples from Frying Pan Creek and 101 paired samples from Harrison Creek were less than the 20 milligrams per liter total maximum daily load. The total maximum daily load was set by the U.S. Environmental Protection Agency for the upper Birch Creek basin in 1996. Suspended-sediment paired-sample data were collected using automated samplers in 2004 and 2005, primarily during low-flow conditions. Suspended-sediment concentrations in grab samples from miscellaneous sites ranged from less than 1 milligram per liter during low-flow conditions to 1,386 milligrams per liter during a high-flow event on upper Birch Creek. Streambed-sediment samples were collected at six sites on Harrison Creek, two sites on Frying Pan Creek, and one site on upper Birch Creek. Trace-element concentrations of mercury, lead, and zinc in streambed sedimen

Scientific Investigations Report↗

USGS2002

Characterization of soils and rock at an active oil production site: Effects of brine and hydrocarbon contamination

An active oil production site (Osage-Skiatook petroleum environmental research Site B) in Osage County, Oklahoma is under study to determine the impacts on soils and rock of brine and hydrocarbon spills. The goals of the soil and rock characterization are to 1) document and identify the type, degree, and areal extent of brine and hydrocarbon releases, 2) understand controls on the movement and retention of brine and hydrocarbons, and 3) determine the role of solid phases, such as clay and iron-bearing minerals, in natural mitigation. The types and amounts of clay minerals and oxidizers (particularly iron) are important because of the capacity of clay minerals to exchange cations that are dissolved in brines and the capacity of reactive ferric iron species to oxidize hydrocarbons. Characterization of soils and rock includes visual and microscopic description, X-ray diffraction of bulk and clay fraction samples, separation of size fractions, determination of cation exchange capacity, bulk chemical composition, and selective extraction of iron species. Results suggest that much of the brine and hydrocarbon contamination occurs in the shallow subsurface (< 240 cm) where the soil profile varies from dark brown topsoil to reddish orange sand to greenish-gray clay. A layer of iron-stained colluvium that is present in the shallow subsurface consists of pebbles and coarse sand and forms an important conduit for fluid movement. Unusually high percentages (as much as 97 % of total iron) of reduced iron may record the passage of hydrocarbon-rich ground water. Clay minerals are abundant in some samples and are dominated by kaolinite, mixed layer illite-smectite, and smectite. The correlation of grain size and clay mineral content with soil leachate results will be discussed and high percentages of sodium on exchange sites in clay are expected in areas of past spills of produced water.

Oklahoma↗

USGS2016

Low-flow characteristics for streams on the Islands of Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi, State of Hawaiʻi

Statistical models were developed to estimate natural streamflow under low-flow conditions for streams with existing streamflow data at measurement sites on the Islands of Kauaʻi, O ʻ ahu, Moloka ʻ i, Maui, and Hawai ʻ i. Streamflow statistics used to describe the low-flow characteristics are flow-duration discharges that are equaled or exceeded between 50 and 95 percent of the time during the 30-year base period 1984–2013. Record-augmentation techniques were applied to develop statistical models relating concurrent streamflow data at the measurement sites and long-term data from nearby continuous-record streamflow-gaging stations that were in operation during the base period and were selected as index stations. Existing data and subsequent low-flow analyses of the available data help to identify streams in under-represented geographic areas and hydrogeologic settings where additional data collection is suggested. Low-flow duration discharges were estimated for 107 measurement sites (including long-term and short-term continuous-record streamflow-gaging stations, and partial-record stations) and 27 index stations. The adequacy of statistical models was evaluated with correlation coefficients and modified Nash-Sutcliff coefficients of efficiency, and a majority of the low-flow duration-discharge estimates are satisfactory based on these regression statistics. Molokaʻi and Hawaiʻi have the fewest number of measurement sites (that are not located on ephemeral stream reaches) at which flow-duration discharges were estimated, which can be partially explained by the limited number of index stations available on these islands that could be used for record augmentation. At measurement sites on some tributary streams, low-flow duration discharges could not be estimated because no adequate correlations could be developed with the index stations. These measurement sites are located on streams where duration-discharge estimates are available at long-term stations at other locations on the main stream channel to provide at least some definition of low-flow characteristics on that stream. In terms of general natural streamflow data availability, data are scarce in the leeward areas for all five islands as many leeward streams are dry or have minimal flow. Other under-represented areas include central Oʻahu, central Maui, and southeastern Maui.

Hawaiʻi↗

USGS2017

Diet, feeding patterns, and prey selection of subyearling Atlantic salmon (Salmo salar) and subyearling chinook salmon (Oncorhynchus tshawytscha) in a tributary of Lake Ontario

Since juvenile Atlantic salmon ( Salmo salar ) and Chinook salmon ( Oncorhynchus tshawytscha ) occupy a similar habitat in Lake Ontario tributaries, we sought to determine the degree of diet similarity between these species in order to assess the potential for interspecific competition. Atlantic salmon, an historically important but currently extirpated component of the Lake Ontario fish community, are the focus of a bi-national restoration effort. Presently this effort includes the release of hatchery produced juvenile Atlantic salmon in Lake Ontario tributaries. These same tributaries support substantial numbers of naturally reproduced juvenile Pacific salmonids including Chinook salmon. Subyearling Atlantic salmon and subyearling Chinook salmon had significantly different diets during each of the three time periods examined. Atlantic salmon fed slightly more from the benthos than from the drift and consumed mainly chirononmids (47.0%) and ephemeropterans (21.1%). The diet of subyearling Chinook salmon was more closely associated with the drift and consisted mainly of chironomids (60.2%) and terrestrial invertebrates (16.0%). Low diet similarity between subyearling Atlantic salmon and subyearling Chinook salmon likely minimizes competitive interactions for food between these species in Lake Ontario tributaries. However, the availability of small prey such as chironomids which comprise over 50% of the diet of each species, soon after emergence, could constitute a short term resource limitation. To our knowledge this is the first study of interspecific diet associations between these two important salmonid species.

Journal of Applied Ichthyology↗

USGS1983

SUBMICROSCOPIC ( less than 1 mu m) MINERAL CONTENTS OF VITRINITES IN SELECTED BITUMINOUS COAL BEDS.

An important aspect of the petrographic description of coal is the characterization of coal quality, including chemical attributes. For geologic investigations, data on the concentrations, distribution, and modes of occurrence of minor and trace elements provide a basis for reconstructing the probable geochemical environment of the swamp material that was converted into peat, and the geochemical conditions that prevailed during and subsequent to coalification. We have been using electron (EPMA) and proton (PIXE) microprobe analytical methods to obtain data on the chemical characteristics of specific coal constituents in their original associations within coal samples. The present study is aimed at evaluation of the nature of mineral occurrences and heterogeneous elemental concentrations within vitrinites. Vitrinites are usually the most abundant, and therefore most important, maceral group in bituminous coal. 8 refs.

Conference Paper↗