These data present the results of sediment toxicity tests conducted by the US Geological Survey's Columbia Environmental Research Center (CERC) in Columbia, MO, in 2014. The sediments were collected as one part of a larger study on stream quality in Southeastern USA streams during the summer of 2014. For more information on the larger study see- https://webapps.usgs.gov/rsqa. The data include results from two test species, the amphipod Hyalella azteca and the midge Chironomus dilutus (formerly known as C. tentans). Three endpoints per species tested are listed as survival, growth and biomass from 76 freshwater stream sediments collected in the study. Values listed are the average response across four test replicates per species, per sediment tested, and are listed as both absolute values per test endpoint and as values normalized to organism performance in reference sediments included within the study. Laboratory testing methods followed standard sediment toxicity test methods for these species from American Society for Testing and Materials (E1706-05(2010)) and US EPA method EPA/600/R-99/064 (2000). For more information about the study and analysis of these results, see associated journal article; 'Moran, P.W., Kemble, N.E., Waite, I.R., Mahler, B.J., Nowell, L.H., Van Metre, P.C. 2020. Legacy and current-use contaminants in sediments limit macroinvertebrate communities in Southeastern USA streams. Environmental Toxicology and Chemistry, in press.

The Grand Calumet River (GCR), located in northern Indiana, is contaminated due to a wide range of historical industrial activities. Short-term and long-term sediment exposure bioassays with the amphipod Hyalella azteca, the midge Chironomus dilutus, and the mussel Lampsilis siliquoidea were conducted with samples collected in 2013, 2015, and 2017, from up to 26 sites, including both remediated, non-remediated and relatively uncontaminated reference sites. The responses (survival, growth, reproduction and/or emergence) of test organisms to the exposure bioassays are presented here.

Data from 10-day sediment toxicity tests of bed sediments from the Niagara River area of concern and tributaries, Niagara and Erie County, New York. Specifically, the data was used to compare the survival and growth of two macroinvertebrate species in sediments from study sites and laboratory controls. Results are from 10-day sediment exposures of two test species, Chironomus dilutus and Hyalella azteca. Bed sediments were collected from depositional areas using either a petite Ponar (0.03 square meter) dredge or a stainless steel sediment scoop. At each site, approximately five grabs or scoops were composited into a bucket, mixed, and a 4-liter (L) subsample was stored in a polyethylene container. Sediment toxicity testing were then conducted by a contract laboratory to quantify toxicity with the dipteran, Chironomus dilutus, and the amphipod, Hyalella azteca, during 10-day survival and growth bioassays following USEPA test methods 100.2 and 100.1, respectively. U.S. Environmental Protection Agency, 2000, Methods for measuring the toxicity and bioaccumulation of sediment associated contaminants with freshwater invertebrates. Second edition: U.S. Environmental Protection Agency, Office of Research and Development EPA 600/R-99/064.http://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=30003SBA.TXT. The data include the year, site ID, and six columns of results from 10-day sediment exposures of two test species, Chironomus dilutus and Hyalella azteca. The following endpoints were measured for each species following the 10-day exposure: percentage of organisms surviving (hereafter survival), average ash-free dry weight of the surviving organisms (hereafter growth), and average ash-free dry weight of the surviving organisms divided by the initial number of organisms (hereafter biomass). Companion to this report: George, S.D., Baldigo, B.P., and Duffy, B.T., 2016, Toxicity of bed sediments from the Niagara River Area of Concern and tributaries, New York, to Chironomus dilutus and Hyalella azteca, 2014–15: U.S. Geological Survey Data Series 1016, XX p., http://dx.doi.org/10.3133/ds1016.

Sediment samples and samples for water-toxicity testing were collected during 2014 from several streams in San Antonio, Texas known locally as the Westside creeks (Alazán, Apache, Martínez, and San Pedro Creeks) and from the San Antonio River. Samples were collected once during base-flow and again after periods of storm-water runoff (post-storm conditions) to determine baseline sediment- and water-quality conditions. Streambed-sediment samples were analyzed for selected constituents, including trace elements and organic contaminants such as pesticides, polychlorinated biphenyls (PCBs), brominated flame retardants, and polycyclic aromatic hydrocarbons (PAHs).

Data from 10-day sediment toxicity tests of bed sediments from the Eighteenmile Creek Area of Concern and Oak Orchard Creek (nearby reference stream), Niagara and Orleans County, New York, respectively. Specifically, the data was used to compare the survival and growth of two macroinvertebrate species in sediments from study sites and laboratory controls. Results are from 10-day sediment exposures of two test species, Chironomus dilutus and Hyalella azteca. Sediment samples were collected from five sites on each stream. Bed-sediments were collected from depositional areas using a petite Ponar (0.03 square meter) dredge. At each site, approximately five grabs were composited into a bucket, mixed, and a 4-liter (L) subsample was stored in a polyethylene container. Sediment toxicity testing were then conducted by a contract laboratory to quantify toxicity with the dipteran, Chironomus dilutus, and the amphipod, Hyalella azteca, during 10-day survival and growth bioassays following USEPA test methods 100.2 and 100.1, respectively. U.S. Environmental Protection Agency, 2000, Methods for measuring the toxicity and bioaccumulation of sediment associated contaminants with freshwater invertebrates. Second edition: U.S. Environmental Protection Agency, Office of Research and Development EPA 600/R-99/064. This spreadsheet contains 13 columns. The first 7 columns describe the sample collection information, the remaining 6 columns provide the survival and growth results of two test species used in sediment toxicity tests. The data include the stream name, site ID, latitude and longitude, replicate number, and site type. Six columns of results from 10-day sediment exposures of two test species, Chironomus dilutus and Hyalella azteca. The following endpoints were measured for each species following the 10-day exposure: number of surviving organisms, percentage of organisms surviving (hereafter survival), and average ash-free dry weight of the surviving organisms (hereafter growth).

This data release contains chemistry and toxicity data from sediment toxicity tests conducted by the USGS Columbia Environmental Research Center (CERC) with 66 sediment samples collected from in and around the Upper Columbia River in the fall of 2013. Toxicity testing was conducted from fall 2013 through summer 2014 with the amphipod, Hyalella azteca, the midge Chironomus dilutus, and the mussel Lampsilis siliquoidea. Short-term toxicity endpoints (10-28 d) included survival, weight, and biomass of all test organisms. Long-term tests with amphipods (42 d) and midges (about 50 d) included reproduction endpoint. Sediments were analyzed for physical and chemical characteristics, including particle size distribution, total organic carbon, acid volatile sulfide, slag content, and concentrations of metals in total-recoverable and simultaneously-extracted fractions. Porewaters were separated by centrifugation and by peepers (diffusion samplers) and were analyzed for filterable metals, dissolved organic carbon, and major ions. These data are intended to be used to characterize concentration-response relationships between metals concentrations and toxicity endpoints and to estimate site-specific toxicity thresholds for select metals or metal mixtures. These thresholds will be used to evaluate risks or injuries to the benthic invertebrate community associated with exposure to contaminated sediments and to develop goals for remediation of sediments of the Upper Columbia River.

These data present chemistry and toxicity results from freshwater stream sediments collected from 99 wadable stream sites across eleven states in the Midwestern U.S. as one component of a larger USGS study in the summer of 2013. This data presents a selected suite of chemistry collected at these sites (PAHs, Organochlorines, PCBs, Trace Elements, and current use pesticides) used in calculating a Probable Effect Concentration-Likely Effect Benchmark quotient mixture score for contaminants measured in sediments. The toxicity data presents results of toxicity tests following ASTM and US EPA standard methods for sediment toxicity tests with the amphipod Hyalella azteca (28-d exposure), the midge Chironomus dilutus (10-d), and at fewer sites, with the freshwater mussel Lampsilis siliquoidea (28-d).

This table summarizes the number of times samples from a location have exceeded an EPA-mandated maximum contaminant level (MCL) since 1990.

USGS conducted preliminary assays on aged (3 mo.) surface sediment (0-4 cm) collected from 13 sites during October 1998 in order to decipher general spatial trends in Hg-speciation, microbiology and relevant biogeochemistry. During the second field campaign sample processing and incubations were conducted at ambient temperature within hours of sediment collection to provide a more accurate measure of in-situ process rates and analyte concentrations. The third field sampling (October 1999), involving 14 sampling and was conducted with a similar approach as in June 1999. The latter two data sets provide a direct seasonal comparison (summer/fall, high/lo flow conditions) of Hg transformation dynamics in the CRS. Sediment depth profiles (0-16 cm) were investigated at four sites during June 1999 and at two of these four during October 1999. Eroding vertical bank material was sampled in the Hg-contaminated Fort Churchill region during both 1999 dates. Laboratory experiments were conducted using sediment collected during the latter two sampling dates. The study purpose sought to: a) identify important zones of net methylmercury (MeHg) production and consumption within the CRS, b) determine which environmental factors most strongly influence these processes and c) provide estimates of seasonal variability. Measurements were made of microbial Hg-transformations (via radiotracer) and in-situ Hg speciation (total mercury (Hgt), MeHg, and particle-associated acid-extractable Hg(II)). Acid extractable Hg(II) was used as a surrogate measure for the Hg(II) most readily available to bacteria for methylation. A novel Hg-biosensor technique was also used to assess bioavailable Hg(II) in pore-water. A suite of ancillary microbial processes and sediment geochemical parameters were also measured to more fully characterize each site, and to relate these measurements to observed Hg-transformation rates and Hg-speciation. The EPA is publishing this data in support of the Carson River Mercury NPL Site in Nevada. Data was compiled and evaluated for the OU2 Remedial Investigation Report (EPA, 2017), which describes the nature and extent of contamination from the Site. The report contains the Human Health Risk Assessment and Ecological Risk Assessment. Literature and other source Hg data are summarized in the RI for surface waters, sediments, and biological tissues.

USGS conducted preliminary assays on aged (3 mo.) surface sediment (0-4 cm) collected from 13 sites during October 1998 in order to decipher general spatial trends in Hg-speciation, microbiology and relevant biogeochemistry. During the second field campaign sample processing and incubations were conducted at ambient temperature within hours of sediment collection to provide a more accurate measure of in-situ process rates and analyte concentrations. The third field sampling (October 1999), involving 14 sampling and was conducted with a similar approach as in June 1999. The latter two data sets provide a direct seasonal comparison (summer/fall, high/lo flow conditions) of Hg transformation dynamics in the CRS. Sediment depth profiles (0-16 cm) were investigated at four sites during June 1999 and at two of these four during October 1999. Eroding vertical bank material was sampled in the Hg-contaminated Fort Churchill region during both 1999 dates. Laboratory experiments were conducted using sediment collected during the latter two sampling dates. The study purpose sought to: a) identify important zones of net methylmercury (MeHg) production and consumption within the CRS, b) determine which environmental factors most strongly influence these processes and c) provide estimates of seasonal variability. Measurements were made of microbial Hg-transformations (via radiotracer) and in-situ Hg speciation (total mercury (Hgt), MeHg, and particle-associated acid-extractable Hg(II)). Acid extractable Hg(II) was used as a surrogate measure for the Hg(II) most readily available to bacteria for methylation. A novel Hg-biosensor technique was also used to assess bioavailable Hg(II) in pore-water. A suite of ancillary microbial processes and sediment geochemical parameters were also measured to more fully characterize each site, and to relate these measurements to observed Hg-transformation rates and Hg-speciation. The EPA is publishing this data in support of the Carson River Mercury NPL Site in Nevada. Data was compiled and evaluated for the OU2 Remedial Investigation Report (EPA, 2017), which describes the nature and extent of contamination from the Site. The report contains the Human Health Risk Assessment and Ecological Risk Assessment. Literature and other source Hg data are summarized in the RI for surface waters, sediments, and biological tissues.