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USGS1993

Diazinon concentrations in the Sacramento and San Joaquin Rivers and San Francisco Bay, California, February 1993

The distribution and possible biological effects of a dormant spray pesticide, diazinon, were examined by measuring pesticide concentrations and estimating toxicity using bioassays at a series of sites in the Sacramento-San Joaquin Delta and San Francisco Bay. Pulses of diazinon were observed in early February 1993 in the Sacramento and San Joaquin Rivers after heavy rains, with elevated concentrations measured for a few days to weeks at a time. The pulse of diazinon in the Sacramento River was followed from Sacramento through Suisun Bay, the eastward embayment of San Francisco Bay. In the central delta, well-defined pulses of diazinon were not observed at the Old and Middle River sites; instead, the concentrations steadily increased throughout February. Ceriodaphnia dubia mortality was 100% in water samples collected for 12 consecutive days (February 8-19) from the San Joaquin River at Vernalis. The bioassay mortality corresponded with the peak diazinon concentrations. Conversely, no toxicity was observed in water collected before or after peaks of diazinon concentration. Other pesticides present also could contribute to the toxicity.

California↗

USGS1997

Characterization of stormwater runoff from the Naval Air Station and Naval Wepons Industrial Reserve Plant, Dallas, Texas, 1994-96

The characterization of stormwater runoff from the Naval Air Station (NAS) and the Naval Weapons Industrial Reserve Plant (NWIRP), Dallas, Texas, is necessary to determine if runoff from the facilities is contributing to off-site contamination of surface waters, A network of five fixed sites and four grab sites was established to collect stormwater-runoff samples from a substantial part of the drainage area of each facility. Fixed sites were instrumented to measure and store precipitation, stage, discharge, and runoff-volume data and to collect flow-weighted composite samples during a storm. Grab and composite samples were collected for six storms at each of the five fixed sites from October 1994 to March 1996. The grab samples were analyzed for about 100 properties and constituents including specific conductance, pH, water temperature, bacteria, trace elements, oil and grease, total phenols, and volatile organic compounds. The composite samples were analyzed for about 220 properties and constituents including specific conductance, pH, chemical oxygen demand, biochemical oxygen demand, major ions, suspended and dissolved solids, nutrients, trace elements, total organic carbon, volatile organic compounds, semivolatile organic compounds, and organochlorine and organophosphorus pesticides. Grab samples were collected for two storms (September 18,1995, and October 2,1995) at each of the four grab sites. The grab samples were analyzed for about 80 constituents including specific conductance, pH, water temperature, trace elements, and volatile organic compounds. Composite samples were collected for two of the six storms sampled at the fixed sites and analyzed for aquatic toxicity. Fathead minnow growth and survival toxicity tests and water flea reproduction and survival toxicity tests were done. Median event-mean concentrations computed for 12 selected constituents in samples from NAS and NWIRP fixed sites were compared to median event-mean concentrations for residential, commercial, industrial, and highway land uses within the Dallas-Fort Worth area computed from data collected for the National Pollutant Discharge Elimination System program. NAS and NWIRP median event-mean concentrations also were compared to those for residential and commercial land uses from the Nationwide Urban Runoff Program.

Open-File Report↗

USGS1999

Reconnaissance of chemical and physical characteristics of selected bottom sediments of the Caloosahatchee River and estuary, tributaries, and contiguous bays, Lee County, Florida, July 20-30, 1998

This report summarizes a reconnaissance study, conducted July 20-30, 1998, of chemical and physical characteristics of recently deposited bottom sediments in the Caloosahatchee River and Estuary. Recently deposited sediments were identified using an isotopic chronometer, Beryllium-7 (7Be), a short-lived radioisotope. Fifty-nine sites were sampled in an area that encompasses the Caloosahatchee River (River) about three miles upstream from the Franklin Lock (S-79), the entire tidally affected length of the river (estuary), and the contiguous water bodies of Matlacha Pass, San Carlos Bay, Estero Bay, Tarpon Bay, and Pine Island Sound in Lee County, Florida. Bottom sediments were sampled for 7Be at 59 sites. From the results of the 7Be analysis, 30 sites were selected for physical and chemical analysis. Sediments were analyzed for particle size, total organic carbon (TOC), trace elements, and toxic organic compounds, using semiquantitative methods for trace elements and organic compounds. The semiquantitative scans of trace elements indicated that cadmium, copper, lead, and zinc concentrations, when normalized to aluminum, were above the natural background range at 24 of 30 sites. Particle size and TOC were used to characterize sediment deposition patterns and organic content. Pesticides, polychlorinated biphenyls (PCBs), and carcinogenic polycyclic aromatic hydrocarbons (CaPAHs) were determined at 30 sites using immunoassay analysis. The semiquantitative immunoassay analyses of toxic organic compounds indicated that all of the samples contained DDT, cyclodienes as chlordane (pesticides), and CaPAHs. PCBs were not detected. Based on analyses of the 30 sites, sediments at 10 of these sites were analyzed for selected trace elements and toxic organic compounds, including pesticides, PCBs, and PAHs, using quantitative laboratory procedures. No arsenic or cadmium was detected. Zinc was detected at two sites with concentrations greater than the lower limit of the range of sediment contaminant concentrations that are usually or always associated with adverse effects (Florida Department of Environmental Protection's Sediment Quality Assessment Guidelines). Organochlorine pesticides were detected at four sites at concentrations below the reporting limits; there were no organophosphorus pesticides or PCBs detected. PAHs were detected at eight sites; however, only four sites had concentrations above the reporting limit.

Florida↗

USGS2005

Geochemical assessment of metals and dioxin in sediment from the San Carlos Reservoir and the Gila, San Carlos, and San Francisco Rivers, Arizona

In October 2004, we sampled stream-bed sediment, terrace sediment, and sediment from the San Carlos Reservoir to determine the spatial and chronological variation of six potentially toxic metals-Cu, Pb, Zn, Cd, As, and Hg. Water levels in the San Carlos Reservoir were at a 20-year low at an elevation of 2,409 ft (734.3 m). Four cores were taken from the reservoir: one from the San Carlos River arm, one from the Gila River arm, and two from the San Carlos Reservoir just west of the Pinal County line. Radioisotope chronometry (7Be, 137Cs, and 210Pb) conducted on sediment from the reservoir cores provides a good chronological record back to 1959. Chronology prior to that, during the 1950s, is based on our interpretation of the 137Cs anomaly in reservoir cores. During and prior to the 1950s, the reservoir was dry and sediment-accumulation rates were irregular; age control based on radioisotope data was not possible. We recovered sediment at the base of one 4-m-long core that may date back to the late 1930s. The sedimentological record contains two discrete events, one about 1978-83 and one about 1957, where the Cu concentration in reservoir sediment exceeded recommended sediment quality guidelines and should have had an effect on sensitive aquatic and benthic organisms. Concentrations of Zn determined in sediment deposited during the 1957(?) event also exceeded recommended sediment quality guidelines. Concentration data for Cu from the four cores clearly indicate that the source of this material was upstream on the Gila River. Lead isotope data, coupled with the geochemical data from a 2M HCl-1 percent H2O2 leach of selected sediment samples, show two discrete populations of data. One represents the dominant sediment load derived from the Safford Valley, and a second reflects sediment derived from the San Francisco River. The Cu concentration spikes in the reservoir cores have chemical and Pb isotope signatures that indicate that deposits in a porphyry copper deposit from the Morenci district is the likely source of these Cu-rich sedimentary deposits. Copper concentrations and Pb isotope data in premining terrace-sediment deposits indicate that the Cu peaks could not have resulted from erosion of premining sediment from terrace deposits downstream on the Gila River. The chemical and Pb isotope data also indicate that agricultural practices in the Safford Valley have resulted in an increased sediment load to the Gila River since large-scale farming began, prior to the time when the San Carlos Reservoir was built. Analyses of dioxin, which is an impurity in one of the herbicides used in the late 1960s and early 1970s, were completed in sediment from one of the cores in the reservoir to determine whether any of these pesticide residues have accumulated in the reservoir sediment. Dioxin concentration is expressed in terms of its toxicity (toxic equivalent concentration or TEQ). Concentrations of dioxin in the sediment ranged from 0.68 to 1.37 pg/g and are less than any of the benchmark concentrations recommended as threshold values for adverse effects of dioxin in sediment (> 2.5-10 pg/g).

Scientific Investigations Report↗

USGS2005

Mass loading of selected major and trace elements in Lake Fork Creek near Leadville, Colorado, September-October 2001

A mass-loading study of Lake Fork Creek of the Arkansas River between Sugarloaf Dam and the mouth was completed in September-October 2001 to help ascertain the following: (1) variation of pH and aqueous constituent concentrations (calcium, sulfate, alkalinity, aluminum, cadmium, copper, iron, manganese, lead, and zinc) and their relation to toxicity standards along the study reach; (2) location and magnitude of sources of metal loading to Lake Fork Creek; (3) amount and locations of metal attenuation; (4) the effect of streamside wetlands on metal transport from contributing mine tunnels; and (5) the effect of organic-rich inflow from the Leadville National Fish Hatchery on water quality in Lake Fork Creek. The study was done in cooperation with the Bureau of Land Management, U.S. Department of Agriculture Forest Service, and U.S. Fish and Wildlife Service. Constituent concentrations and pH showed variable patterns over the study reach. Hardness-based acute and chronic toxicity standards were exceeded for some inflows and some constituents. However, stream concentrations did not exceed standards except for zinc starting in the upper parts of the study reach and extending to just downstream from the inflow from the Leadville National Fish Hatchery. Dilution from that inflow lowered stream zinc concentrations to less than acute and chronic toxicity standards. The uppermost 800 meters of the study reach that contained inflow from the Bartlett, Dinero, and Nelson mine tunnels and the Dinero wetland was the greatest source of loading for manganese and zinc. A middle section of the study reach that extended approximately 2 kilometers upstream from the National Fish Hatchery inflow to just downstream from that inflow was the largest source of aluminum, copper, iron, and lead loading. The loading was partially from the National Fish Hatchery inflow but also from unknown sources upstream from that inflow, possibly ground water. The largest sources for calcium and sulfate load to the stream were the parts of the study reach containing inflow from the tribu-taries Halfmoon Creek (calcium) and Willow Creek (sulfate). The Arkansas River and its tributaries upstream from Lake Fork Creek were the source of most of the calcium (70 percent), sulfate (82 percent), manganese (77 percent), lead (78 percent), and zinc (95 percent) loads in the Arkansas River downstream from the Lake Fork confluence. In contrast, Lake Fork Creek was the major source of aluminum (68 percent), copper (65 percent), and iron (87 percent) loads to the Arkansas River downstream from the confluence. Attenuation was not important for calcium, sulfate, or iron. However, other metals loads were reduced up to 81 percent over the study reach (aluminum, 25 percent; copper, 20 percent; manganese, 81 percent; lead, 30 percent; zinc, 72 percent). Metal attenuation in the stream occurred primarily in three locations (1) the irrigation diversion ditch; (2) the beaver pond complex extending from upstream from the Colorado Gulch inflow to just downstream from that inflow; and (3) the stream reach that included the inflow from Willow Creek. The most likely attenuation mechanism is precipitation of metal oxides and hydroxides (primarily manganese), and sorption or coprecipitation of trace elements with the precipitating phase. A mass-balance calculation indicated that the wetland between the Dinero Tunnel and Lake Fork Creek removed iron, had little effect on zinc mass load, and was a source for, or was releasing, aluminum and manganese. In contrast, the wetland that occurred between the Siwatch Tunnel and Lake Fork Creek removed aluminum, iron, manganese, and zinc from the tunnel drainage before it entered the creek. Inflow from the National Fish Hatchery increased dissolved organic carbon concentrations in Lake Fork Creek and slightly changed the composition of the dissolved organic carbon. However, dissolved organic carbon loads increased in the stream reach downs

Colorado↗

USGS2010

Effects of Highway Road Salting on the Water Quality of Selected Streams in Chittenden County, Vermont, November 2005-2007

A study of road-deicing chloride (Cl) concentrations and loads was conducted at three streams in Chittenden County, VT, from November 2005 to 2007. This study was done by the U.S. Geological Survey, in cooperation with the Vermont Agency of Transportation. The streams, Alder Brook, Allen Brook, and Mill Brook, were selected to represent different land uses in the upstream watershed, different road types and densities, and different geometric patterns of the roadway draining to the receiving stream to assess the relative contribution of and differences in state road-salt applications to stream Cl concentrations and loads. Water-quality samples were collected and specific conductance was measured continuously at paired stations upstream and downstream from State highways and related to Cl concentrations to assist in determining the effects of road-salting operations during winter maintenance on the levels of Cl in the streams. Mean concentrations of Cl ranged from 8.2 to 72 mg/L (milligrams per liter) in the water-quality samples collected at sampling stations upstream from State highway bridges and from 7.9 to 80 mg/L in those collected at sampling stations downstream of highway bridges. Mean Cl loads ranged from 1,100 to 4,090 lb/d (pounds per day) at upstream stations and from 1,110 to 4,200 lb/d at downstream stations. Estimated mean annual Cl loads ranged from 402,000 to 1,490,000 lb/yr (pounds per year) at upstream stations and from 405,000 to 1,530,000 lb/yr at downstream stations. Mean Cl concentrations in samples collected at the three paired stations were lowest at Mill Brook at VT 117 near Essex Junction, VT (7.9 mg/L) and highest at Allen Brook at VT 2A near Essex Junction, VT (80.7 mg/L). None of the monitored Cl concentrations in the water-quality samples collected at the three paired sampling stations exceeded either of the U.S. Environmental Protection Agency's (USEPA) recommended chronic and acute Cl toxicity criteria of 230 and 860 mg/L, respectively. A fourth stream site, a small tributary draining to Alder Brook between the upstream and downstream stations, was monitored from December 2006 to November 2007. This tributary collected runoff from a state highway and an interchange before flowing through a wetlands retention basin. The mean Cl concentration in water-quality samples collected at the tributary was 449 mg/L. The USEPA recommended chronic toxicity criterion of 230 mg/L was exceeded about 65 percent of the monitoring period. The USEPA recommended acute toxicity criterion of 860 mg/L was not exceeded. Estimated Cl loads below the State highway bridges exceeded loads above the bridges at all three paired stations during both years of the study. The differences in the annual loads between the upstream and downstream stations were 0.7, 3.0 and 14 percent at Mill, Allen, and Alder Brooks, respectively. Almost all of the difference (92 percent) at Alder Brook was due to the tributary. Cl applied by the State of Vermont for deicing purposes represented less than 20 percent of the annual estimated Cl load in all 3 streams below the state highways. The highest monthly Cl loads during the first year of the study were observed in January 2006 at all three stream stations because of an early snowmelt event. The highest monthly Cl loads during the second year of the study were observed in April 2007 at all three streams during spring snowmelt and were followed by decrease in Cl loading through the summer. Generally, the relation of Cl loads to runoff was similar at all three streams. In July and October 2007, loads increased slightly with an increase in runoff, indicating that Cl in the soils and groundwater may be contributing to the Cl levels during the summer and fall, well after the road-salting season. Cl loads in all three streams appear to be due primarily to sources in the watersheds upstream of the state highway bridge where road salt was applied and (or) Cl retained in soils and streambed

Scientific Investigations Report↗

USGS2011

Occurrence and distribution of pesticides in surface waters of the Hood River basin, Oregon, 1999-2009

The U.S. Geological Survey analyzed pesticide and trace-element concentration data from the Hood River basin collected by the Oregon Department of Environmental Quality (ODEQ) from 1999 through 2009 to determine the distribution and concentrations of pesticides in the basin's surface waters. Instream concentrations were compared to (1) national and State water-quality standards established to protect aquatic organisms and (2) concentrations that cause sublethal or lethal effects in order to assess their potential to adversely affect the health of salmonids and their prey organisms. Three salmonid species native to the basin are listed as "threatened" under the U.S. Endangered Species Act: bull trout, steelhead, and Chinook salmon. A subset of 16 sites was sampled every year by the ODEQ for pesticides, with sample collection targeted to months of peak pesticide use in orchards (March-June and September). Ten pesticides and four pesticide degradation products were analyzed from 1999 through 2008; 100 were analyzed in 2009. Nineteen pesticides were detected: 11 insecticides, 6 herbicides, and 2 fungicides. Two of four insecticide degradation products were detected. All five detected organophosphate insecticides and the one detected organochlorine insecticide were present at concentrations exceeding water-quality standards, sublethal effects thresholds, or acute toxicity values in one or more samples. The frequency of organophosphate detection in the basin decreased during the period of record; however, changes in sampling schedule and laboratory reporting limits hindered clear analysis of detection frequency trends. Detected herbicide and fungicide concentrations were less than water-quality standards, sublethal effects thresholds, or acute toxicity values. Simazine, the most frequently detected pesticide, was the only herbicide detected at concentrations within an order of magnitude (factor of 10) of concentrations that impact salmonid olfaction. Some detected pesticides are of concern, not for their toxicity alone, but for their ability to potentiate the harmful impacts of other pesticides, particularly organophosphates, on salmonids or their prey. Many samples contained mixtures of pesticides, but the effects to salmonids of relevant mixtures at environmentally realistic concentrations for the basin are unknown. Trace-element concentration data, although limited, indicate that eight trace elements are also of concern for their potential to harm salmonid health. The dataset is limited with regard to the spatial and seasonal distribution of pesticides and trace elements in all salmonid-bearing streams, the presence of particle-bound pesticides, and the presence of several unmonitored pesticides known to be used in the basin.

Oregon↗

USGS2012

Reconnaissance of contaminants in selected wastewater-treatment-plant effluent and stormwater runoff entering the Columbia River, Columbia River Basin, Washington and Oregon, 2008-10

Toxic contamination is a significant concern in the Columbia River Basin in Washington and Oregon. To help water managers and policy makers in decision making about future sampling efforts and toxic-reduction activities, a reconnaissance was done to assess contaminant concentrations directly contributed to the Columbia River through wastewater-treatment-plant (WWTP) effluent and stormwater runoff from adjacent urban environments and to evaluate instantaneous loadings to the Columbia River Basin from these inputs. Nine cities were selected in Oregon and Washington to provide diversity in physical setting, climate characteristics, and population density—Wenatchee, Richland, Umatilla, The Dalles, Hood River, Portland, Vancouver, St. Helens, and Longview. Samples were collected from a WWTP in each city and analyzed for anthropogenic organic compounds, pharmaceuticals, polychlorinated biphenyls (PCBs), polybrominated diphenyl ether (PBDEs [brominated flame-retardants]), organochlorine or legacy compounds, currently used pesticides, mercury, and estrogenicity. Of the 210 compounds analyzed in the WWTP-effluent samples, 112 (53 percent) were detected, and the detection rate for most compound classes was greater than 80 percent. Despite the differences in location, population, treatment type, and plant size, detection frequencies were similar for many of the compounds detected among the WWTPs. By contrast, the occurrence of polycyclic aromatic hydrocarbons (PAHs) was sporadic, and PCBs were detected at only three WWTPs. The stormwater-runoff samples were analyzed for a slightly different set of contaminants, with the focus on those expected to be related to road and land runoff—PCBs, PBDEs, organochlorine compounds, PAHs, currently used pesticides, trace elements, mercury, and oil and grease. A complex mixture of compounds was detected in stormwater runoff, with detections of 114 (58 percent) of the 195 compounds analyzed. The detection patterns and concentrations measured in the stormwater-runoff samples, however, were more heterogeneous than in the WWTP-effluent samples. This reflects differences in various factors, including suspended-sediment concentrations and known contamination sources present in some watersheds. Trace elements and PAHs, which are related to automobiles and impervious surfaces, were the most widespread compound classes detected in stormwater runoff, a typical finding in stormwater runoff in urban areas. With a better understanding of the presence of these contaminants in the environment, future work can focus on developing research to characterize the effects of these contaminants on aquatic life and prioritize toxic-reduction efforts for the Columbia River Basin.

Washington;Oregon↗

USGS2015

Trace-metal and organic constituent concentrations in bed sediment at Big Base and Little Base Lakes, Little Rock Air Force Base, Arkansas—Comparisons to sediment-quality guidelines and indications for timing of exposure

This report compares concentrations for a wide range of inorganic and organic constituents in bed sediment from Big Base Lake and Little Base Lake, which are located on Little Rock Air Force Base, Arkansas, to sediment-quality guidelines. This report also compares trace-metal concentrations in a bed-sediment core sample to sediment age to determine when the highest concentrations of trace metals were deposited in Big Base Lake. Trace-metal results often were higher than background concentrations in the surrounding Pulaski County area, and concentrations of arsenic, cadmium, cobalt, copper, lead, manganese, mercury, nickel, and zinc at one or more of three study sites were higher than median concentrations for a study involving 98 urban streams in seven metropolitan areas of the United States. Concentrations for most polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine pesticides in all three bed-sediment samples were less than the laboratory reporting limit or were detected at low concentrations. Some contaminants were detected at concentrations that are potentially toxic to sediment-dwelling biota; however, in general, the analyses suggest that the risk of sediment toxicity may be relatively low. Threshold effect concentrations were exceeded for 14 constituents—arsenic, copper, lead, nickel, and zinc, five polycyclic aromatic hydrocarbons compounds, chlordane, and all three dichlorodiphenyltrichloroethane (DDT) congeners—which suggests potential toxicity to some sediment-dwelling biota. Only two constituents had concentrations that exceeded published probable effect concentrations—arsenic (at the deepest site in Big Base Lake, NS6) and p,p’-dichlorodiphenyldichloroethylene (p,p’-DDE; at both sites in Big Base Lake, NS5 and NS6). Regarding highest concentrations and associated timing of exposure, trace metals analyzed in the sediment core seem to indicate three fairly distinct exposure patterns. For 11 trace metals that had the highest concentration measured in the shallowest and most recently deposited sediment, the most likely explanation is recent exposure by anthropogenic activities. Most of the 11 trace metals with highest concentrations in shallow sediment are relatively innocuous; however, arsenic, copper, selenium, and zinc are among the U.S. Environmental Protection Agency’s 126 priority pollutants. For three trace metals (cadmium, lead, and mercury), for which concentrations were highest in sediments that were 16–20 centimeters down the core, it is likely that a source associated with those contaminants during the period when those sediments were deposited, was reduced or eliminated. The eight remaining trace metals, for which concentrations were highest in sediments that were just below the prereservoir surface, likely had sources that were eliminated soon after lake construction or occurred at relatively high background concentrations in soils in the area around Little Rock Air Force Base.

Arkansas↗

USGS2002

Water Quality of Camp Creek, Costello Creek, and Other Selected Streams on the South Side of Denali National Park and Preserve, Alaska

The Camp and Costello Creek watersheds are located on the south side of Denali National Park and Preserve. The Dunkle Mine, an abandoned coal mine, is located near the mouth of Camp Creek. Due to concern about runoff from the mine and its possible effects on the water quality and aquatic habitat of Camp Creek and its receiving stream, Costello Creek, these two streams were studied during the summer runoff months (June to September) in 1999 and 2000 as part of a cooperative study with the National Park Service. Since the south side of Denali National Park and Preserve is part of the U.S. Geological Survey?s National Water-Quality Assessment Cook Inlet Basin study unit, an additional part of this study included analysis of existing water-quality data at 23 sites located throughout the south side of Denali National Park and Preserve to compare with the water quality of Camp and Costello Creeks and to obtain a broader understanding of the water quality in this area of the Cook Inlet Basin. Analysis of water column, bed sediment, fish, invertebrate, and algae data indicate no effects on the water quality of Camp Creek from the Dunkle Mine. Although several organic compounds were found in the streambed of Camp Creek, all concentrations were below recommended levels for aquatic life and most of the concentrations were below the minimum reporting level of 50 ?g/kg. Trace element concentrations of arsenic, chromium, and nickel in the bed sediments of Camp Creek exceeded threshold effect concentrations (TEC), but concentrations of these trace elements were also exceeded in streambed sediments of Costello Creek above Camp Creek. Since the percent organic carbon in Camp Creek is relatively high, the toxicity quotient of 0.55 is only slightly above the threshold value of 0.5. Costello Creek has a relatively low organic carbon content and has a higher toxicity quotient of 1.19. Analysis of the water-quality data for other streams located in the south side of Denali National Park and Preserve indicate similarities to Camp Creek and Costello Creek. Most of the streams are calcium bicarbonate/calcium bicarbonate-sulfate type water with the exception of two streams that are calcium sulfate and magnesium sulfate type water. Trace element concentrations of arsenic, chromium, and nickel in the bed sediments of 9 streams exceeded the TEC or the probable effect concentration (PEC). Seven streams exceeded the threshold value of the toxicity quotient. Analysis of trace element concentrations in bed sediment and basin characteristics for 16 watersheds by cluster and discriminant analysis techniques indicated that the watersheds could be separated into two groups based on their basin characteristics.

Water-Resources Investigations Report↗

USGS1988

Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Sun River area, west-central Montana, 1986-87

The Sun River area was selected for a reconnaissance investigation of irrigation drainage because sufficient information existed to indicate that potential problems of a toxic nature might exist. The area of study included the Sun River Irrigation Project, Freeze-out Lake Game Management Area, and Benton Lake National Wildlife Refuge. Water, bottom sediment , and biota were sampled at selected sites and analyzed for inorganic and organic constituents that could be toxic at large concentrations. Although selenium was of primary concern, other trace elements and selected pesticides were also analyzed. Some water quality problems have been prevalent for many years in the Sun River Irrigation Projects, including the Sun River and Muddy Creek. However, during this study, most sampling sites were free of concentrations of toxic constituents that are in excess of established criteria and standards. There was little change in arsenic, boron, mercury, and selenium concentrations in fish and invertebrates at Sun River sampling sites upstream and downstream from the irrigation project. Presently, the most serious threat within the irrigation project appears to be from nitrate in groundwater. Water from some wells contains nitrate concentration in excess of drinking water standards (10 mg/L) established for the State of Montana. The largest selenium concentrations in water and bottom sediment were from seeps that surround Benton Lake, with maximum concentrations of 580 mg/L in water and biological samples. Several eared-grebe livers from Freezeout Lake and several coot livers and eggs from Benton Lake had selenium concentrations indicative of contamination. (See also W89-07064) (Author 's abstract)

Water-Resources Investigations Report↗

USGS1993

Water quality, organic chemistry of sediment, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee

An investigation of water quality, organic sediment chemistry, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee, was conducted during December 1990. The study was designed to assess the extent of possible contamination of water and biota in the streams from creosote-related discharge originating at this Superfund site. Central Creek, adjacent to the plant, had degraded water quality and biological conditions. Water samples from the most downstream station on Central Creek contained 30 micrograms per liter of pentachlorophenol, which exceeds the State's criterion maximum concentrations of 9 micrograms per liter for fish and aquatic life. Bottom-sediment samples from stations on Central Creek contained concentrations of acenaphthene, napthalene, and phenanthrene ranging from 1,400 to 2,500 micrograms per kilogram. Chronic or acute toxicity resulted during laboratory experiments using test organisms exposed to creosote-related contaminants. Sediment elutriate samples from Central Creek caused slightly to highly toxic effects on Ceriodaphnia dubia. Pimephales promelas, and Photobacterium phosphoreum. Fish-tissue samples from this station contained concentrations of naphthalene. dibenzofuran, fluorene, and phenanthrene ranging from 1.5 to 3.9 micrograms per kilogram Blue-green algae at this station represented about 79 percent of the organisms counted, whereas diatoms accounted for only 11 percent. Benthic invertebrate and fish samples from Central Creek had low diversity and density. Sediment samples from a station on the South Fork Forked Deer River downstream from its confluence with Central Creek contained concentrations of acenaphthene, anthracene, chrysene, fluoranthene, fluorene, pyrere, and phenanthrene ranging from 2,800 to 69,000 micrograms per kilogram. Sediment elutriate samples using water as elutriate from this station contained concentrations of extractable organic compounds ranging from an estimated 43 to 420 micrograms per liter. Sediment elutriate samples were toxic to Ceriodaphnia dubta, Pimephales promelas, Photobacterium phosphoreum, and Salenastrum capricornulum.

Water-Resources Investigations Report↗

USGS1988

National water summary 1986: Hydrologic events and ground-water quality

Ground water is one of the most important natural resources of the United States and degradation of its quality could have a major effect on the welfare of the Nation. Currently (1985), ground water is the source of drinking water for 53 percent of the Nation's population and for more than 97 percent of its rural population. It is the source of about 40 percent of the Nation's public water supply, 33 percent of water for irrigation, and 17 percent of freshwater for selfsupplied industries. Ground water also is the source of about 40 percent of the average annual streamflow in the United States, although during long periods of little or no precipitation, ground-water discharges provide nearly all of the base streamflow. This hydraulic connection between aquifers and streams implies that if a persistent pollutant gets into an aquifer, it eventually could discharge into a stream. Information presented in the 1986 National Water Summary clearly shows that the United States has very large amounts of potable ground water available for use. Although naturally occurring constituents, such as nitrate, and human-induced substances, such as synthetic organic chemicals, frequently are detected in ground water, their concentrations usually do not exceed existing Federal or State standards or guidelines for maximum concentrations in drinking water. Troublesome contamination of ground water falls into two basic categories related to the source or sources of the contamination. Locally, high concentrations of a variety of toxic metals, organic chemicals, and petroleum products have been detected in ground water associated with point sources such as wastedisposal sites, storage-tank leaks, and hazardous chemical spills. These types of local problems commonly occur in densely populated urban areas and industrialized areas. Larger, multicounty areas also have been identified where contamination frequently is found in shallow wells. These areas generally are associated with broad-scale, or nonpoint, sources of contamination such as agricultural activities or highdensity domestic waste disposal (septic systems) in urban centers. At present, only a very small percentage of the total volume of potable ground water in the United States is contaminated from both point and nonpoint sources; however, available data, especially data about the occurrence of synthetic organic and toxic substances, generally are inadequate to determine the full extent of ground-water contamination in the Nation's aquifers or to define trends in groundwater quality. Most information about the occurrence of these substances has come from the study of individual sites or areas where contamination had already been detected or suspected. Management and protection of ground water present a major challenge to the Nation. Current and projected costs of detection and cleanup of existing ground-water contamination are staggering and, even so, complete removal of pollutants from ground water in the vicinity of some waste sites might not be technically feasible. At all levels of government, the task of protecting the resource for its most beneficial uses is difficult and controversial. Despite increasing awareness that some of the Nation's ground water is contaminated with a variety of toxic metals, synthetic organic chemicals, radionuclides, pesticides, and other contaminants that might present a long-term risk to human health, public policy towards ground-water protection is still in the formative stages. Despite increasing efforts devoted to ground-water protection by State and Federal regulatory and resource-management agencies, the extent of ground-water contamination is likely to appear to increase over the next few years because more agencies will be searching for evidence of contamination, and they will be using increasingly sensitive analytical procedures. Increased technology and expanded monitoring activities probably will detect the effects of past contamination and land uses on water quality. The significant time lag between a waterquality change in one part of an aquifer system and the effects of that change at a downgradient site, such as a well, results from the generally slow movement of ground water. This lag between cause and observed effect needs to be considered in evaluating the effectiveness of current and future ground-water policies and remedial measures. Conclusive answers to questions about the location, extent, and severity of ground-water contamination, and about trends in ground-water quality, must await further collection and analysis of data from the Nation's aquifers. Generalizations, however, can be made, and the 1986 National Water Summary, which describes the natural quality of ground-water resources in each State and the major contamination problems that have been identified as of 1986, provides a national perspective of the ground-water-quality situation. The 1986 National Water Summary follows the format of previous volumes. It contains three parts, and the contents of each of these parts are highlighted below.

Water Supply Paper↗

USGS2023

Survival and growth of juvenile mussels in an outdoor pond after 28-day laboratory exposure to aqueous zinc

The extent to which effects seen in chronic toxicity studies in the laboratory affect mussel fitness later in life is poorly known. We examined juvenile Fatmucket ( Lampsilis siliquoidea ) survival and growth for 56 d following exposure to Zn in a laboratory bioassay. We conducted a 28-d chronic toxicity bioassay with 6-wk-old juvenile mussels exposed to a control and two Zn treatments (120 and 240 µg/L). We then transferred surviving mussels into a grow-out pond and monitored their survival and growth for 56 d. Survival and shell length were lower in both Zn treatments than in the control after the 28-d toxicity bioassay. After the 56-d grow-out period, survival did not differ among treatments, but shell length was lower in the 240-µg/L treatment than in the control and mass was lower in both Zn treatments than in the control. Mussel length was lower throughout the experiment in both Zn treatments than in the control, but there was weak support for a difference in the slopes, suggesting that Zn-exposed mussels may fall farther behind in size over time. Persistence of reduced size following Zn exposure could result in delayed sexual maturation and lowered fecundity, which could have long-term population-level effects.

Freshwater Mollusk Biology and Conservation↗

USGS2020

Assessment of burrowing behavior of freshwater juvenile mussels in sediment

Standard laboratory sediment toxicity methods have been adapted for conducting toxicity tests with juvenile freshwater mussels. However, studies looking at juvenile mussel burrowing behavior at the water-sediment interface are limited. Juvenile mussels burrow in sediment for the first 0 to 4 yr of life but also may inhabit the sediment-water interface. The objective of this study was to evaluate burrowing behavior of various species and ages of juvenile freshwater mussels in three control sediments: West Bearskin Lake, Spring River, and coarse commercial sand. Species tested included (1) Fatmucket ( Lampsilis siliquoidea ), (2) Notched Rainbow ( Villosa constricta ), (3) Washboard ( Megalonaias nervosa ), (4) Rainbow ( Villosa iris) , (5) Arkansas Fatmucket ( Lampsilis powellii ), and (6) Oregon Floater ( Anodonta oregonensis ). Greater than 95% of the mussels burrowed into test sediment within 15 min. Across species, life stage, and substrate type, most mussels were recovered from the upper layers of sediment (91% at a sediment depth of 3.4 mm or less), and only 2% of the mussels were recovered at a depth >5.1 mm. No mussels were recovered from a depth >6.8 mm. There was no difference in mussel burrowing depth at 4 h versus 24 h across species, age, and sediment type. Two ages of Fatmucket burrowed to a significantly greater depth in the West Bearskin Lake sediment compared to the Spring River sediment or Coarse Sand. However, there was no significant difference in mean depth across sediment type with the other five species of mussels tested. Based on species and age of mussels tested, juvenile mussels up to an age of at least 20 wk and a length of at least 5 mm readily burrow into sediment and likely would be exposed to contaminants in whole sediment and associated pore water throughout a laboratory sediment toxicity test.

Freshwater Mollusk Biology and Conservation↗

USGS2018

Effects of temperature and exposure duration on four potential rapid-response tools for zebra mussel (Dreissena polymorpha) eradication

Zebra mussels (Dreissena polymorpha) have continued their spread within inland lakes and rivers in North America despite diligent containment and decontamination efforts by natural resource agencies and other stakeholders. Identification of newly infested waterways by early detection surveillance programs allows for rapid response zebra mussel eradication treatments in some situations. Previous eradication treatments have occurred over a broad range of water temperatures which have influenced the efficacy of molluscicides. Natural resource managers will benefit from knowledge regarding the impacts of water temperature and exposure duration on the toxicity of molluscicides to zebra mussels. In particular, temperature specific data are needed to inform the selection of an effective molluscicide and the proper dose that will induce 100% zebra mussel mortality. We evaluated the influences of temperature and exposure duration on the toxicity of two U.S. EPA-registered (EarthTec QZ and Zequanox) and two nonregistered (niclosamide and potassium chloride) molluscicides to zebra mussels at water temperatures of 7, 12, 17, and 22 °C. Our results indicate that treatment options for the eradication of zebra mussels in waters ≤ 12 °C include 336 h or longer treatments with EarthTec QZ and KCl as well as treatments with niclosamide ≥ 24 h in duration. In waters ≥ 17 °C, multiple toxicant and exposure duration combinations are potentially effective for zebra mussel eradication. On-site or in situ zebra mussel bioassays are a useful tool for the evaluation of treatment efficacy.

Management of Biological Invasions↗

USGS2023

Antimycin A species sensitivity distribution: Perspectives for non-indigenous fish control

The global transfer of aquatic biota outside their native geographical range has resulted in dramatic changes to biological communities. Many nonnative species introductions are facilitated by human activity and then spread intra-continentally through connected watersheds once established. Resource managers therefore utilize multiple control technologies, such as management chemicals, for fisheries management to remove non-indigenous fishes. Antimycin-A (ANT-A) is a management chemical, previously registered in the United States, that has been extensively studied and used to control non-indigenous fishes. The present study examines ANT-A species sensitivity among fish and aquatic invertebrates and summarizes factors that influence toxicity. ANT-A species sensitivity distributions 20th percentile hazard concentrations (HC20) for acute studies ≤ 24 h demonstrated fish (0.088 µg/L) are 174-fold more sensitive to ANT-A than invertebrates (15.35 µg/L). Similar to previous reports, toxicity was demonstrated to be influenced by water pH, temperature, and fish mass. Therefore, the present study and results characterize ANT-A toxicity for aquatic resource managers and future use in fisheries management.

Management of Biological Invasions↗

USGS2011

Survival and growth of newly transformed Lampsilis cardium and Lampsilis siliquoidea in a flow-through, continuous feeding test system

A test system was evaluated for assessing chronic toxicity of waterborne chemicals with early life stage mussels. To determine if the test system could result in ≥80% survival in a control (unexposed) group, fat mucket mussels ( Lampsilis siliquoidea Barnes, 1823) and plain pocketbook mussels ( L. cardium Rafinesque, 1820) 1 day post transformation were stocked into test chambers (250 mL beakers, water volume, 200 mL, 21 °C, 40 mussels of 1 species per chamber) within a test system constructed for conducting chronic, continuous exposure, flow-through toxicity tests. The test system contained 60 chambers containing silica sand, 30 chambers with L. siliquoidea , and 30 with L. cardium . Each chamber in the continuous feeding system received 1 of 6 food types prepared with concentrated algal products. After 28 days, mussels were harvested from chambers to assess survival and growth. For L. siliquoidea , mean survival ranged from 34 to 80% and mean shell length ranged from 464 to 643 µm. For L. cardium , mean survival ranged from 12 to 66% and mean shell length ranged from 437 to 612 µm. The maximum mean growth rate for L. siliquoidea was 12.7 µm/d and for L. cardium was 11.8 µm/d. When offered a continuous diet of Nannochloropsis, Tetraselmis , and Chlorella for 28 days in the test system, the survival of 1 day post transformation L. siliquoidea was 80%. The test system can be easily enhanced with a pumping system continuously delivering test chemical to the test system's flow stream allowing for chronic toxicity tests with 1 day post transformation mussels.

American Malacological Bulletin↗