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USGS2003

Seabird tissue archival and monitoring project: Egg collections and analytical results 1999-2002

In 1998, the U.S. Geological Survey Biological Resources Division (USGS-BRD), the U.S. Fish and Wildlife Service (USFWS) Alaska Maritime National Wildlife Refuge (AMNWR), and the National Institute of Standards and Technology (NIST) began the Seabird Tissue Archival and Monitoring Project (STAMP) to collect and cryogenically bank tissues from seabirds in Alaska for future retrospective analysis of anthropogenic contaminants. The approach of STAMP was similar to that of the Alaska Marine Mammal Tissue Archival Project (AMMTAP). AMMTAP was started in 1987 by NIST and the National Oceanic and Atmospheric Administration (NOAA) as part of the Outer Continental Shelf Environmental Assessment Program sponsored by the Minerals Management Service. Presently sponsored by the USGS-BRD, AMMTAP continues its work as part of a larger national program, the Marine Mammal Health and Stranding Response Program. AMMTAP developed carefully designed sampling and specimen banking protocols. Since 1987, AMMTAP has collected tissues from marine mammals taken in Alaska Native subsistence hunts and has cryogenically banked these tissues at the NIST National Biomonitoring Specimen Bank (NBSB). Through its own analytical work and working in partnership with other researchers both within and outside Alaska, AMMTAP has helped to develop a substantial database on contaminants in Alaska marine mammals. In contrast, data and information is limited on contaminants in Alaska seabirds, which are similar to marine mammals in that they feed near the top of the food chain and have the potential for accumulating anthropogenic contaminants. During its early planning stages, STAMP managers identified the seabird egg as the first tissue of choice for study by the project. There is a relatively long history of using bird eggs for environmental monitoring and for investigating the health status of bird populations. Since 1998, protocols for collecting and processing eggs, and cryogenically banking egg samples have been developed by STAMP (see York et al. 2001). Eggs are being collected on an annual basis for several species at nesting colonies throughout Alaska. Aliquots of these egg samples are being analyzed on a regular basis for persistent organic pollutants and mercury. Results of this work have been published in scientific journals (Christopher et al. 2002) and in conference proceedings (Kucklick et al. 2002; Vander Pol et al. 2002a, 2002b). The intent of this report is to provide an up-to-date description of STAMP. The report contains the most recent egg collection inventory, analytical data, preliminary interpretations based on these data, and a discussion of possible future directions of the project.

Report↗

USGS1996

Comparison of gas chromatography/mass spectrometry and immunoassay techniques on concentrations of atrazine in storm runoff

Gas chromatography/mass spectrometry (GC/MS) and enzyme-linked immunosorbent assay (ELISA) techniques were used to measure concentrations of dissolved atrazine in 149 surface-water samples. Samples were collected during May 1992–September 1993 near the mouth of the White River (Indiana) and in two small tributaries of the river. GC/MS was performed on a Hewlett-Packard 5971 A, with electron impact ionization and selected ion monitoring of filtered water samples extracted by C-18 solid phase extraction; ELISA was performed with a magnetic-particle-based assay with photometric analysis. ELISA results compared reasonably well to GC/MS measurements at concentrations below the Maximum Contaminant Level for drinking water set by the U.S. Environmental Protection Agency (3.0 μg/L), but a systematic negative bias was observed at higher concentrations. When higher concentration samples were diluted into the linear range of calibration, the relation improved. A slight positive bias was seen in all of the ELISA data compared to the GC/MS results, and the bias could be partially explained by correcting the ELISA data for cross reactivity with other triazine herbicides. The highest concentrations of atrazine were found during the first major runoff event after the atrazine was applied. Concentrations decreased throughout the rest of the sampling period even though large runoff events occurred during this time, indicating that most atrazine loading to surface waters in the study area occurs within a few weeks after application. Use of brand names is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey, the Uniroyal Chemical Company, or Wichita State University.

Indiana↗

USGS1999

Environmental characteristics associated with the occurrence of avian botulism in wetlands of a northern California refuge

Avian botulism is an important disease affecting many species of waterbirds in North America, but the environmental conditions that initiate outbreaks are poorly understood. To determine wetland attributes associated with outbreaks of avian botulism in waterbirds at the Sacramento National Wildlife Refuge (SNWR), California, we compared environmental characteristics between wetlands where outbreaks occurred (outbreak wetlands) and did not occur (nonoutbreak wetlands). In June through October, 1987 89, we monitored the occurrence of avian botulism via observations for sick or dead sentinel mallards (Anas platyrhynchos) placed in 4 wetland enclosures. During this same time period, we collected environmental data from the water column and sediments of each wetland enclosure at 10 14-day sampling intervals. Multivariate analysis was used to reduce 22 environmental variables to 7 factors for inclusion in subsequent statistical analyses. We found that outbreak wetlands had significantly lower redox potential than nonoutbreak wetlands. The probability of botulism in sentinel mallards was associated with increasing temperature, increasing invertebrate abundance or biomass, and decreasing turbidity. However, because these factors were not consistently higher in outbreak wetlands compared to nonoutbreak wetlands, they may have a more proximate effect in initiating an outbreak.

California↗

USGS2010

Land Disturbance Associated with Oil and Gas Development and Effects of Development-Related Land Disturbance on Dissolved-Solids Loads in Streams in the Upper Colorado River Basin, 1991, 2007, and 2025

Oil and gas resource development in the Upper Colorado River Basin (UCRB) has increased substantially since the year 2000. The UCRB encompasses several significant oil and gas producing areas that have the potential for continued oil and gas resource development. Land disturbance associated with oil and gas resource development is caused by activities related to constructing drill pads to contain drilling and well maintenance equipment and roads to access the drill pad. Land disturbed by oil and gas development has the potential to cause increased erosion, stream degradation, habitat fragmentation and alteration, and increase public use of areas that may be environmentally sensitive. Land disturbance resulting from oil and gas resource development has not been monitored and mapped on a regional scale in the UCRB. However, information on the location and age of oil and gas wells in the UCRB is available. These data combined with geographic data analysis and modeling techniques were used to estimate the total area of disturbed land associated with oil and gas resource development in 1991 and in 2007 in the UCRB. Additional information about anticipated oil and gas development in the UCRB was used to project land disturbance to the year 2025. Results of the analysis indicate that approximately 117,500 acres (183 mi2) of total land disturbance was associated with drill pads and related roads in the UCRB in 1991. The estimated area of disturbed land associated with oil and gas development increased 53 percent to 179,400 acres (280 mi2) in 2007. Projecting oil and gas development through 2025 results in a potential near doubling of the land surface disturbance to approximately 319,300 acres (500 mi2). Estimated land disturbance for 1991 and 2007 were input to a contaminant transport model developed for the UCRB to assess the statistical significance of energy-related land disturbance to contributing dissolved solids to basin streams. The statistical assessment was an observational study based on an existing model and available water-quality monitoring data for the basin. No new data were collected for the analysis. The source coefficient calibrated for the disturbed lands associated with oil and gas development in 2007 was zero, which indicated that estimated land disturbance from oil and gas development is not statistically significant in explaining dissolved solids in UCRB streams. The lack of significance in the contaminant transport modeling framework may be due to the amount of available monitoring data, the spatial distribution of monitoring sites with respect to land disturbance, or the overall quantity of land disturbance associated with oil and gas development basin wide. Finally, dissolved-solids loads derived from natural landscapes may be similar to loads derived from lands disturbed by oil and gas resource development. The model recalibration done for this study confirms calibration results from Kenney and others (2009): the most significant contributor to dissolved solids in the UCRB is irrigated agricultural land, which covers an area substantially larger than the estimated area disturbed by oil and gas development and is subjected to artificially applied water.

Scientific Investigations Report↗

USGS2016

Changes in phosphorus concentrations and loads in the Assabet River, Massachusetts, October 2008 through April 2014

Treated effluent discharged from municipal wastewater-treatment plants to the Assabet River in central Massachusetts includes phosphorus, which leads to increased growth of nuisance aquatic plants that decrease the river’s water quality and aesthetics in impounded reaches during the growing season. To improve the river’s water quality and aesthetics, the U.S. Environmental Protection Agency approved a total maximum daily load for phosphorus in 2004 that directed the wastewater-treatment plants to reduce the amount of total phosphorus discharged to the river by 2012. The permitted total phosphorus monthly average of 0.75 milligrams per liter during the aquatic plant growing season (April 1 through October 31) was reduced by the total maximum daily load to a target of 0.1 milligrams per liter by 2012, and the nongrowing-season limit was unchanged at 1.0 milligrams per liter. From October 2008 through April 2014, the U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, measured streamflow and collected weekly flow-proportional, composite samples of water from the Assabet River for analysis of concentrations of total phosphorus and orthophosphate. Streamflow and concentration data were used to estimate total phosphorus and orthophosphate loads in the river. The purpose of this monitoring effort was to evaluate phosphorus concentrations and loads in the river before, during, and after the wastewater-treatment-plant upgrades and to assess the effects of seasonal differences in permitted discharges. The locations of water-quality-monitoring stations, with respect to the Hudson and Ben Smith impoundments, enabled examination of effects of phosphorus entering and leaving the impoundments. Annual median concentrations of total phosphorus in wastewater-treatment plants were reduced by more than 80 percent with the plant upgrades. Measured instream annual median concentrations of total phosphorus in the Assabet River decreased by about 38 to 50 percent at three of the four monitoring stations following the wastewater-treatment-plant upgrades. At the station farthest upstream, the median total phosphorus concentration remained unchanged throughout the study; this may be attributed to the site location and potential resuspension of particulate organic matter during periods of increased streamflow. Annual median loads from the wastewater-treatment plants were reduced by up to 91 percent following the upgrades, instream annual median total phosphorus loads at the three downstream stations decreased by 71 to 76 percent, and instream orthophosphate loads at the three downstream stations decreased by 79 to 87 percent. Seasonal fluctuations (growing versus nongrowing) of total phosphorus and orthophosphate were observed instream before the upgrades. However, after the upgrades, fluctuations in phosphorus released from the treatment plants were slight and seasonal changes were typically not observed instream. Annual loads entering and leaving the two impoundments were inconclusive in determining whether the impoundments were sources or sinks of total phosphorus during the study. Total phosphorus loads entering the Hudson impoundment were consistently greater than those leaving; however, there was uncertainty about the loads at the monitoring station upstream from this impoundment. At the Ben Smith impoundment, total phosphorus and orthophosphate loads downstream were slightly greater than those upstream from the impoundment, but the differences may reflect additions from tributaries and overland runoff. Estimated instream total phosphorus concentrations and loads indicated that the decreases in total phosphorus in wastewater-treatment-plant discharges were accompanied by reductions measured in the Assabet River. A statistical analysis which incorporates the effect of varying flow conditions demonstrated significant reductions in total phosphorus concentrations after the wastewater-treatment-plant upgrades at three of the four instream monitoring stations. No significant change was observed at the most upstream location, the Assabet River at Port Street at Hudson, Massachusetts (station number 01096835), which may have been affected by flow-related resuspension of particulate phosphorus.

Massachusetts↗

USGS2009

Summary and analysis of water-quality data for the Arrowwood National Wildlife Refuge, east-central North Dakota, 1987-2004

The Bureau of Reclamation collected water-quality samples at 16 sites on the James River and the Arrowwood National Wildlife Refuge, N. Dak., as part of its refuge-monitoring program from 1987-93 and as part of an environmental impact statement commitment from 1999-2004. Climatic and hydrologic conditions varied greatly during both sampling periods. The first period was dominated by drought conditions, which abruptly changed to cooler and wetter conditions in 1992-93. During the second period, conditions were near normal to very wet and included higher inflow from the James River into the refuge. The two periods also differed in the sites sampled, seasons sampled, and properties and constituent concentrations measured. Summary statistics were reported separately for the two sampling periods for all physical properties and constituents. Nonparametric statistical tests were used to further analyze some of the water-quality data. During the first sampling period, 1987-93, specific conductance, turbidity, hardness, alkalinity, total dissolved solids, total suspended solids, nonvolatile suspended solids, calcium, magnesium, sodium, potassium, sulfate, chloride, phosphate, total phosphorus, total organic carbon, chlorophyll a, and arsenic were determined to have significantly different medians among the sites tested. During the second sampling period, 1999-2004, the medians of pH, sodium, chloride, barium, and boron varied significantly among sites. Sites sampled and period of record varied between the two sampling periods and the period of record varied among the sites. Also, some constituents analyzed during the first period (1987-93) were not analyzed during the second period (1999-2004), and winter sampling was done during the second sampling period only. This variability reduces the number of direct comparisons that can be made between the two periods. Three sites had complete periods of record for both sampling periods and were compared. Differences in variability and median concentration were identified between the two time periods. Sites representing inflow to the refuge and outflow were compared statistically for the period when data were available for both sites, 1999-2004. Of the nutrients tested - ammonia plus organic nitrogen, phosphate, and total phosphorus - no significant statistical differences were found between the inflow samples and the outflow samples. Statistically significant differences were found for pH, sulfate, chloride, barium, and manganese. Nutrients are of particular interest in the refuge because of the aquatic plant and animal life and the use of the wetland resources by waterfowl. However, the nutrient data were highly censored and there were differences in the seasonal timing of sample collection between the two sampling periods. Therefore, the nutrient data were examined graphically with stripplots that highlighted differences in the seasonal timing of sample collection and concentration differences likely related to the differences in climatic and hydrologic conditions between the two periods.

North Dakota↗

USGS1999

Fraser River watershed, Colorado — Assessment of available water-quantity and water-quality data through water year 1997

The water-quantity and water-quality data for the Fraser River watershed through water year 1997 were compiled for ground-water and surface-water sites. In order to assess the water-quality data, the data were related to land use/land cover in the watershed. Data from 81 water-quantity and water-quality sites, which consisted of 9 ground-water sites and 72 surface-water sites, were available for analysis. However, the data were limited and frequently contained only one or two water-quality analyses per site. The Fraser River flows about 28 miles from its headwaters at the Continental Divide to the confluence with the Colorado River. Ground-water resources in the watershed are used for residential and municipal drinking-water supplies. Surface water is available for use, but water diversions in the upper parts of the watershed reduce the flow in the river. Land use/land cover in the watershed is predominantly forested land, but increasing urban development has the potential to affect the quantity and quality of the water resources. Analysis of the limited ground-water data in the watershed indicates that changes in the land use/land cover affect the shallow ground-water quality. Water-quality data from eight shallow monitoring wells in the alluvial aquifer show that iron and manganese concentrations exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level. Radon concentrations from these monitoring wells exceeded the U.S. Environmental Protection Agency proposed maximum contaminant level. The proposed radon contaminant level is currently being revised. The presence of volatile organic compounds at two monitoring wells in the watershed indicates that land use affects the shallow ground water. In addition, bacteria detected in three samples are at concentrations that would be a concern for public health if the water was to be used as a drinking supply. Methylene blue active substances were detected in the ground water at some sites and are a possible indication of contamination from wastewater. Age of the alluvial ground water ranged from 10 to 30 years; therefore, results of land-management practices to improve water quality may not be apparent for many years. Surface-water-quality data for the Fraser River watershed are sparse. The surface-water-quality data show that elevated concentrations of selected constituents generally are related to specific land uses in the watershed. For one sample (about 2 percent; 1 of 53), dissolved manganese concentration exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level. Two samples from two surface-water sites in the watershed exceeded the un-ionized ammonia chronic criterion. Spatial distribution of nutrient species (ammonia, nitrite, nitrate, and total phosphorus) shows that elevated concentrations occur primarily downstream from urban areas. Sites with five or more years of record were analyzed for temporal trends in concentration of nutrient species. Downward trends were identified for ammonia and nitrite for three surface-water sites. For nitrate, no trends were observed at two sites and a downward trend was observed at one site. Total phosphorus showed no trend for the site near the mouth of the Fraser River. Downward trends in the nutrient species may reflect changes in the wastewater-treatment facilities in the watershed. Bacteria sampling completed in the watershed indicates that more bacteria are present in the water near urban settings. The limited ground-water and surface-water data for the Fraser River watershed provide a general assessment of the quantity and quality of these resources. Concentrations of most water-quality constituents generally are less than ground- and surface-water-quality standards, but the presence of bacteria, some volatile organic compounds, methylene blue active substances, and increased nutrients in the water may indicate that land use is affecting the water quality.

Colorado↗

USGS2022

Aquatic vegetation dynamics in the Upper Mississippi River over 2 decades spanning vegetation recovery

Macrophytes have recovered in rivers across the world, but long-term data and studies are lacking regarding community assembly and diversity changes coincident with macrophyte recovery. We investigated patterns of aquatic vegetation species composition and diversity in thousands of sites in the Upper Mississippi River, USA, spanning 21 y of monitoring and a period of vegetation recovery. We analyzed site-level compositional dissimilarity and environmental associations using non-metric multidimensional scaling, compared stability of lake-level assemblages over time with convex hulls, and assessed shared trends in assemblage dissimilarity at the pool scale using dynamic factor analysis. Site-level differences in aquatic vegetation assemblage structure were associated with water depth and substrate, and a gradient of species abundance and diversity was apparent. A common trend in assemblage dissimilarity over time and across contiguous floodplain lakes indicate that assemblage composition changed and diversity increased with considerable synchrony within the past 21 y. Shared trends across the 400-km study reach are indicative of 1 or more widespread, common drivers; however, neither hydrologic extremes nor turbidity explained vegetation assemblage patterns. Following several years of strong changes in composition and increased diversity, the vegetation assemblage displayed signs of increasing stability in some pools but not others. Further research is needed to identify drivers and mechanisms of aquatic vegetation assemblage expansion, assembly, and resilience, all of which will be applicable to the recovery of aquatic vegetation in floodplain systems worldwide.

Illinois, Iowa, Minnesota, Wisconsin↗

USGS1995

Bioindicators used in aquatic and terrestrial monitoring

There are many different types of contaminants present in the environment ranging from synthetic chemicals, which would not be present in the environment without man's intervention, to trace metals that are required for life. Concerns range from possible harmful effects on flora and fauna to possible harm to humans consuming such organisms. The complete chemical analysis for all possible environmental contaminants in sediments, water, air, and every species and sample of interest would not only be excessively costly, but the facilities to handle do many samples do not exist. Such chemical analysis would only establish the presence of contaminants, without revealing how available or active they were within the organism. Bioindicators, sometimes called biomarkers , are responses in living organisms that may simply signify exposure to contaminants, may predict future harm, or may themselves be harmful effects. In this chapter, a bioindicator will be interpreted to mean the same as a biomarker (a biochemical, physiological, or morphological response), but not a population or ecosystem bioindicator such as a sentinel species, genetic variability, or species richness. thus, a bioindicator (biomarker) may be studied in a particular species to assess the status of that species, or in a sentinel species to assess habitat status. Individuals of the sentinel species might be those already residing at the site of interest or might be pristine organisms brought to the site and maintained in cages (fish) or released and recovered (birds).

Book chapter↗

USGS1999

Interaction of ambient conditions and fecal coliform bacteria in southern Lake Michigan beach waters: Monitoring program implications

Excessive fecal coliform bacteria in public swimming waters can potentially threaten visitor health. Fecal coliform bacteria (1984-1989) and Escherichia coli (1990-1995) density were monitored weekly at the Indiana Dunes National Lakeshore beaches for 12 summers, and park officials closed swimming areas when fecal coliform density exceeded the state water quality criteria (400 CFU fecal coliforms/ 100 ml; 235 CFU E. coli/100 ml water). Due to a 24-hour incubation in the fecal coliform and E. coli assays, beaches were closed the day after collection of high fecal coliform. Our analysis suggests that it is not possible to predict one day's fecal coliform count based on the previous day's results in waters taken from southern Lake Michigan beaches. Dispersal and deposition of bacteria were not uniform among sites or across time apparently due to interactions among environmental variables including rainfall, wind direction, water temperature, and bacteria source. Rainfall combined with northwest winds increased bacteria concentrations. Escherichia coli followed a seasonal trend with similar fluctuations in density among beaches. We suggest that the current beach monitoring protocol is inadequate for predicting fecal coliform density at the time of beach closure, and, subsequently, its use for ensuring visitor safety remains questionable.

Indiana↗

USGS2009

Chloride in Groundwater and Surface Water in Areas Underlain by the Glacial Aquifer System, Northern United States

A study of chloride in groundwater and surface water was conducted for the glacial aquifer system of the northern United States in forested, agricultural, and urban areas by analyzing data collected for the National Water-Quality Assessment Program from 1991 to 2004. Groundwater-quality data from a sampling of 1,329 wells in 19 states were analyzed. Chloride concentrations were greater than the secondary maximum contaminant level established by the U.S. Environmental Protection Agency of 250 milligrams per liter in 2.5 percent of samples from 797 shallow monitoring wells and in 1.7 percent of samples from 532 drinking-water supply wells. Water samples from shallow monitoring wells in urban areas had the largest concentration of chloride, followed by water samples from agricultural and forested areas (medians of 46, 12, and 2.9 milligrams per liter, respectively). An analysis of chloride:bromide ratios, by mass, and chloride concentrations compared to binary mixing curves for dilute groundwater, halite, sewage and animal waste, potassium chloride fertilizer, basin brines, seawater, and landfill leachate in samples from monitoring wells indicated multiple sources of chloride in samples from wells in urban areas and agricultural areas. Water from shallow monitoring wells in urban areas had the largest chloride:bromide ratio, and samples with chloride:bromide ratios greater than 1,000 and chloride concentrations greater than 100 milligrams per liter were dominated by halite; however, the samples commonly contained mixtures that indicated input from sewage or animal waste. Chloride:bromide ratios were significantly larger in samples from public-supply drinking-water wells than from private drinking-water wells, and ratios were significantly larger in all drinking-water wells in eastern and central regions of the glacial aquifer system than in west-central and western regions of the glacial aquifer system. Surface-water-quality data collected regularly during varying time periods from 1991-2004 from 100 basins dominated by forested, agricultural, or urban land in 15 states were analyzed to determine maximum measured chloride concentrations. Samples from 15 sites in east, central, and west-central areas, collected primarily in winter, had chloride concentrations higher than the U.S. Environmental Protection Agency recommended chronic criterion concentration for aquatic life of 230 milligrams per liter. Concentrations of chloride in base-flow samples were predictive of maximum measured chloride concentrations, indicating that inputs of chloride from groundwater and (or) point-source wastewater discharges increase the likelihood of samples exceeding the recommended chronic aquatic criterion. Multiple linear regression analyses showed that the density of major roads, potential evapotranspiration, and the percentage of annual runoff from saturated overland flow were significant factors in describing the range of maximum measured chloride concentrations in the basins studied. Chloride loads and yields were determined at 95 surface-water-monitoring stations in basins dominated by forested, agricultural, or urban land. Annual chloride yield was largest in the urban basins (median of 88 tons per square mile) and smallest in the forested basins (median of 6.4 tons per square mile). The median chloride yield in the agricultural basins was 15.4 tons per square mile. Multiple linear regression analyses showed that the density of highways (roads in U.S. highway system), the number of major wastewater discharges in the basin, potential evapotranspiration, and urban minus agricultural land area were significant factors in describing the range of average annual chloride yields. Upward trends in chloride loads were apparent in several urban basins for which additional long-term data were available. Increases in chloride loads over time may be related to a variety of factors, including increases in road area and consequent deicing, incr

Scientific Investigations Report↗

USGS2024

An integrated analysis for estimation of survival, growth, and movement of unmarked juvenile anadromous fish

Managers invest substantial resources to promote recovery of declining anadromous fish stocks. Recovery strategies are manifold and often include management actions intended to stimulate somatic growth, increase in-river survival, and motivate juvenile outmigration during favorable environmental conditions. Evaluating the efficacy of these management actions is difficult, however, because monitoring data that explicitly track individuals from egg deposition to juvenile outmigration are typically lacking. We developed an integrated population model that links two different and often collected types of anadromous fish monitoring data: spawning ground surveys and rotary screw trap juvenile catch data. The integrated model accounts for incomplete detection and uses the two sources of data to estimate juvenile demographic parameters in a multistate framework. We evaluated the model's performance using simulated data under a range of conditions typically encountered in similar surveys. Simulation results indicated that the model estimated juvenile survival, growth, and movement with no-to-minimal bias (i.e., ≥ 50 % of simulations ± 0–0.05). As an example case study, we fit the model to empirical fall-run Chinook Salmon ( Oncorhynchus tshawytscha ) monitoring data collected in California's Central Valley, U.S.A. In doing so, we evaluated the influence of environmental conditions (e.g., discharge, water temperature) and habitat availability on juvenile demographic rates. We demonstrated that through our integrated approach we could estimate state transition probabilities that are typically inestimable for naturally produced, unmarked juvenile fish when using traditional statistical approaches to analyze these types of monitoring data. Furthermore, the structure of our model can serve as a useful foundation for decision-support models within adaptive management programs by directly linking management actions, decision-support-model predictions, and monitoring.

California↗

USGS1998

Analysis of the sensitivity of soils to the leaching of agricultural pesticides in Ohio

Pesticides have not been found frequently in the ground waters of Ohio even though large amounts of agricultural pesticides are applied to fields in Ohio every year. State regulators, including representatives from Ohio Environmental Protection Agency and Departments of Agriculture, Health, and Natural Resources, are striving to limit the presence of pesticides in ground water at a minimum. A proposed pesticide management plan for the State aims at protecting Ohio's ground water by assessing pesticide-leaching potential using geographic information system (GIS) technology and invoking a monitoring plan that targets aquifers deemed most likely to be vulnerable to pesticide leaching. The U.S. Geological Survey, in cooperation with Ohio Department of Agriculture, assessed the sensitivity of mapped soil units in Ohio to pesticide leaching. A soils data base (STATSGO) compiled by U.S. Department of Agriculture was used iteratively to estimate soil units as being of high to low sensitivity on the basis of soil permeability, clay content, and organic-matter content. Although this analysis did not target aquifers directly, the results can be used as a first estimate of areas most likely to be subject to pesticide contamination from normal agricultural practices. High-sensitivity soil units were found in lakefront areas and former lakefront beach ridges, buried valleys in several river basins, and parts of central and south- central Ohio. Medium-high-sensitivity soil units were found in other river basins, along Lake Erie in north-central Ohio, and in many of the upland areas of the Muskingum River Basin. Low-sensitivity map units dominated the northwestern quadrant of Ohio.

Water-Resources Investigations Report↗

USGS2018

Relationships between indicators of acid-base chemistry and fish assemblages in streams of the Great Smoky Mountains National Park

The acidity of many streams in the Great Smoky Mountains National Park (GRSM) has increased significantly since pre-industrial (∼1850) times due to the effects of highly acidic atmospheric deposition in poorly buffered watersheds. Extensive stream-monitoring programs since 1993 have shown that fish and macroinvertebrate assemblages have been adversely affected in many streams across the GRSM. Matching chemistry and fishery information collected from 389 surveys performed at 52 stream sites over a 22-year period were assessed using logistic regression analysis to help inform the U.S. Environmental Protection Agency’s assessment of the environmental impacts of emissions of oxides of nitrogen (NO x ) and sulfur (SO x ). Numerous logistic equations and associated curves were derived that defined the relations between acid neutralizing capacity (ANC) or pH and different levels of community richness, density, and biomass; and density and biomass of brook trout, rainbow trout, and small prey (minnow) populations in streams of the GRSM. The equations and curves describe the status of fish assemblages in the GRSM under contemporary emission levels and deposition loads of nitrogen (N) and sulfur (S) and provide a means to estimate how newly proposed (and various alternative) target deposition loads, which strongly influence stream ANC, might affect key ecological indicators. Several examples using ANC, community richness, and brook trout density are presented to illustrate the steps needed to predict how future changes in stream chemistry (resulting from different target deposition loads of N and S) will affect the probabilities of observing specific levels of selected biological indicators in GRSM streams. The implications of this study to the regulation of NO x and SO x emissions, water quality, and fisheries management in streams of the GRSM are discussed, but also qualified by the fact that specific examples provided need to be further explored before recommendations concerning their use as ecological indicators could be proposed.

North Carolina, Tennessee↗

USGS2015

Concentration comparison of selected constituents between groundwater samples collected within the Missouri River alluvial aquifer using purge and pump and grab-sampling methods, near the city of Independence, Missouri, 2013

The U.S. Geological Survey, in cooperation with the City of Independence, Missouri, Water Department, has historically collected water-quality samples using the purge and pump method (hereafter referred to as pump method) to identify potential contamination in groundwater supply wells within the Independence well field. If grab sample results are comparable to the pump method, grab samplers may reduce time, labor, and overall cost. This study was designed to compare constituent concentrations between samples collected within the Independence well field using the pump method and the grab method. Relative percent differences between environmental grab and duplicate grab samples were greater than 10 percent for 80 percent of the constituents. Duplicate grab samples were collected by tethering two grab samplers together, because the amount of water collected by each grab sampler is close to the amount necessary for analysis. The screened interval lengths of monitoring wells within the Independence well field is not conducive to collecting multiple grab samples by tethering samplers. The inability to collect required duplicate quality assurance samples may limit the use of grab samplers. Concentrations between pump and grab samples were similar for analyzed nutrient species, the variability between methods was less than the variability between historical duplicate samples, and there were no significant differences determined. Major ion relative percent differences were less than 10 percent and root mean square error differences between methods and between historical duplicate samples were less than 1 milligram per liter with the exception of sulfate. Statistically significant differences were determined between pump and grab samples for sodium and fluoride. There is a strong association between major ion pump and grab samples based on bivariate plots and simple linear regressions. Variability between pump and grab samples of analyzed nutrients and major ions may have minimal effect on the ability to monitor temporal changes and potential groundwater contamination threats. Relative percent differences between methods were greater than 10 percent for most analyzed trace elements. Barium, cobalt, manganese, and boron had concentrations that were significantly different between sampling methods. Barium, molybdenum, boron, and uranium method concentrations indicate a close association between pump and grab samples based on bivariate plots and simple linear regressions. Grab sample concentrations were generally larger than pump concentrations for these elements and may be because of using a larger pore sized filter for grab samples. Analysis of zinc blank samples suggests zinc contamination in filtered grab samples. Variations of analyzed trace elements between pump and grab samples could reduce the ability to monitor temporal changes and potential groundwater contamination threats. The degree of precision necessary for monitoring potential groundwater threats and application objectives need to be considered when determining acceptable variation amounts.

Missouri↗

USGS2004

Preliminary results of a dam-removal analysis on brewster creek near st. Charles, Illinois, 2002-2004

The benefits of gradually removing a dam (through multiple notches) are to reduce the total project cost and reduce possible environmental effects by allowing the impounded sediment to slowly move downstream, and a stable stream and revegetated floodplain to form upstream. Notching, in this study of a dam on Brewster Creek, near St. Charles, Illinois, involves cutting a given height (in five 12-18 inch notches over approximately a 9 month period) across the length (or some portion of the length) of the dam. Brewster Creek is a tributary of the Fox River in northeastern, Illinois. Sediment, dissolved oxygen, and geomorphic response are being monitored before, during, and after a gradual (notching) removal of the dam. The study area includes the creek reach immediately below the dam and above the lake. Preliminary data analysis indicate that during and after the removal, the relation between the sediment transported to the study area from upstream and the sediment transported out of the study area remained relatively stable. This preliminary result indicates that the notching system created a fairly slow and predictable sediment transport response to storms, when compared to known upstream sediment loads. This result corresponds to the slow geomorphic response at the site since inception of the notching sequence in 2003. The creek responded to the five notches removed over the course of 9 months by gradually cutting through the former lakebed sediment to establish a meandering channel. Notchings did not appreciably affect dissolved oxygen concentrations in Brewster Creek.

Conference Paper↗

USGS2011

Using regional-scale pre- and post Hurricane Katrina lidar for monitoring and modeling: Chapter 30

Hurricane Katrina was one of the largest natural disasters in U.S. history. Due to the sheer size of the affected areas, an unprecedented regional analysis at very high resolution and accuracy was needed to properly quantify and understand the effects of the hurricane and the storm tide. Many disparate sources of lidar data were acquired and processed for varying environmental reasons by pre- and post-Katrina projects. The datasets were in several formats and projections and were processed to varying phases of completion, and as a result the task of producing a seamless digital elevation dataset required a high level of coordination, research, and revision. This completed integration allowed for regional-scale storm surge modeling based on very high-resolution elevation information.

Louisiana, Mississippi↗

USGS2021

Geologic and hydrogeologic characteristics of the White River Formation, Lance Formation, and Fox Hills Sandstone, northern greater Denver Basin, southeastern Laramie County, Wyoming

In cooperation with the Wyoming State Engineer’s Office, the U.S. Geological Survey studied the geologic and hydrogeologic characteristics of Cenozoic and Upper Cretaceous strata at a location in southeastern Laramie County within the Wyoming part of the Cheyenne Basin, the northern subbasin of the greater Denver Basin. The study aimed to improve understanding of the aquifers/aquifer systems in these strata, motivated in part by declining groundwater levels and interest in exploring future groundwater supplies. Based on detailed geologic characterization using information obtained by drilling and coring a 960-foot-(ft) deep exploratory borehole, and comparisons with previously published descriptions, identified Cenozoic lithostratigraphic units included 40 ft of Quaternary older alluvial fan deposits consisting of an unconsolidated mixture of sand and gravel with lesser quantities of silt and clay in varying proportions and the underlying 407.3-ft-thick White River Formation of late Eocene-Oligocene age consisting largely of mudrocks with sparse thin beds of sandstone, muddy gravel, and conglomeratic mudrocks. Identified Upper Cretaceous lithostratigraphic units included the 351.6-ft-thick Lance Formation, consisting of terrestrial sedimentary rocks including mudrocks (muddy shale and silty and sandy shale, siltstone, claystone, and mudstone) interbedded with much smaller quantities of very fine- to medium-grained muddy and silty sandstone and coal; the 79.6-ft-thick Fox Hills Sandstone, consisting of a transitional marine sequence of muddy or silty sandstone present in five individual beds; and 86.7 ft of the upper transition member of the Pierre Shale, consisting largely of marine sedimentary rocks such as muddy shale. Beds of the upper and lower Fox Hills Sandstone were separated by tongues of the Lance Formation and upper transition member of the Pierre Shale, respectively. The White River hydrogeologic unit, consisting of the entire White River Formation or Group at the study site, did not contain any substantial secondary permeability features in the mudrocks that composed almost all the unit. A monitoring well (BR–1) was completed in the White River aquifer with the well screen open to the only coarse-grained unit (muddy sandstone) that had sufficient thickness and permeability to be considered as an aquifer. Sampling of the well for a broad suite of constituents indicated groundwater generally was of excellent quality except dissolved arsenic was detected at a concentration greater than the U.S. Environmental Protection Agency (EPA) Maximum Contaminant Level, and dissolved sodium was measured at a concentration greater than several EPA Drinking Water Advisory Levels (DWAs) for the constituent. Well development, well purging for groundwater sampling, and calculated aquifer properties indicated the sandstone aquifer screened by monitoring well BR–1 was not very productive. Analysis of the well water-level responses in BR–1 to atmospheric loading and Earth tides indicated the responses were consistent with a confined-aquifer response with wellbore-storage effects. Hydraulic properties estimated based on these responses yielded values of hydraulic conductivity ( K , 0.057 foot per day [ft/d]), specific storage ( Ss , 1.6×10 −6 per foot [ft −1 ]) and porosity ( n , 0.43). Water levels filtered to remove the effects of atmospheric loading and Earth tides indicated an upward trend (+1.13 foot per year [ft/yr]) during the period analyzed, September 5, 2014, to September 30, 2017. Lithologic characteristics of the Lance hydrogeologic unit, consisting of the entire Lance Formation at the study site, indicated a potential aquifer in a “sandy” interval in the upper part of the unit. Most of the Lance hydrogeologic unit below the “sandy” interval consisted of various low-permeability lithologies unlikely to yield substantial quantities of water. This lower part of the hydrogeologic unit likely functions as a confining unit separating the underlying Lance-Fox Hills aquifer. A geologic cross section constructed for this study indicated fine-grained sediments composed most of the Lance Formation/hydrogeologic unit not only at the study location, but also throughout southern Laramie County along the line of section and throughout the Wyoming and Colorado parts of the Cheyenne Basin. A monitoring well (LN–1) completed in a sandstone bed in the “sandy” interval of the Lance hydrogeologic unit produced a mean of about 23 gallons per minute (gal/min) during well development, indicating sandstone beds can form moderately productive confined subaquifers in this part of the hydrogeologic unit. Analysis of the well water-level responses in well LN–1 to atmospheric loading and Earth tides indicated the responses were consistent with a confined-aquifer response. Hydraulic properties estimated based on these responses yielded values for a lower bounding K of 0.60 ft/d, Ss of 1.6×10 −6 ft −1 , and n of 0.38. Water levels filtered to remove the effects of atmospheric loading and Earth tides indicated a downward trend (−0.86 ft/yr) during the period analyzed (November 8, 2014, to September 30, 2017). Analyses for a broad suite of constituents in samples from well LN–1 indicated groundwater quality generally was excellent, although dissolved sodium was measured at a concentration greater than two EPA DWA levels for the constituent. Because of the absence of any overlying or intertonguing sandstone beds belonging to the lower/basal part of the Lance Formation, the Lance-Fox Hills aquifer at the study site consisted only of the five sandstone beds of the Fox Hills Sandstone. The cross section constructed for this study illustrated how the Fox Hills Sandstone, and thus, most of the Lance-Fox Hills aquifer, consists of a series of sandstone bodies that overlap (shingle) upward to the east across southern Laramie County. These bodies collectively form a fairly continuous body of sandstone, thus potentially forming an areally extensive aquifer across southern Laramie County, and by extension, throughout most of the formation’s extent in the Wyoming part of the Cheyenne Basin, as is the case in the Colorado part of the basin. A monitoring well (FH–1) completed in part of the thickest sandstone bed of the Lance-Fox Hills aquifer was moderately to highly productive and easily produced 25 to 30 gal/min after development. Substantially larger water production rates likely could be obtained by penetrating the full thickness of this bed and by completing a well open to the other overlying and underlying sandstone beds of the aquifer. Analysis of the water-level responses in well FH–1 to atmospheric loading and Earth tides indicated the responses were consistent with a confined-aquifer response. Hydraulic properties computed based on these responses yielded values for a lower bounding estimate for K of 0.26 ft/d, for Ss of 1.0×10 −6 ft −1 , and for n of 0.41. Water levels filtered to remove the effects of atmospheric loading and Earth tides indicated a downward trend (−1.74 ft/yr) during the period analyzed, December 19, 2014, to September 30, 2017. Sampling of monitoring well FH–1 and two production wells completed in the Fox Hills Sandstone in other parts of Laramie County indicated groundwater quality generally is excellent, although pH exceeded a recommended EPA aesthetic drinking-water standard (Secondary Maximum Contaminant Level) in two of three sampled wells, total dissolved solids concentrations exceeded the Secondary Maximum Contaminant Level in one of the two sampled production wells, and dissolved sodium was measured in all three sampled wells at a concentration greater than two EPA DWA levels for the constituent. The Wyoming Class II agricultural (irrigation) sodium adsorption ratio standard of 8 was exceeded in all three sampled wells, indicating these waters are not suitable for irrigation use. Computed vertical hydraulic gradients indicated a strong potential for downward flow throughout the groundwater system at the study site, including from the low-yielding aquifer in the upper White River Formation/hydrogeologic unit (monitoring well BR–1) to the sandstone subaquifer in the Lance Formation/hydrogeologic unit (monitoring well LN–1), and from the Lance subaquifer (monitoring well LN–1) to the sandstone bed/aquifer that composes much of the Lance-Fox Hills aquifer thickness at the study site (monitoring well FH–1). However, large hydraulic-head differences between wells indicated high resistance to vertical flow attributable to the low vertical hydraulic conductivity of intervening strata, which consisted almost entirely of low-permeability mudrocks. The confined nature of the sandstone aquifers monitored by the various wells coupled with dissimilarities between groundwater-level fluctuations and trends in groundwater levels indicated downward flow through the intervening strata (primarily mudrocks in the various lithostratigraphic/hydrogeologic units) between the examined sets of wells likely was small.

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