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This data release contains bioassay 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. These data are intended to be used to characterize concentration-response relationships between metals concentrations...
Samples were submitted for contract laboratory analysis as part of a study examining the occurrence of chromium and natural and anthropogenic hexavalent Chromium, Cr(VI) in groundwater. Data will be used to estimate naturally-occurring background Cr(VI) concentrations upgradient, near the plume margins, and downgradient from a mapped Cr(VI) contamination plume near Hinkley, CA (Izbicki and Groover, 2016). These Contract Lab results are part of the data release including grain-size distribution, photographic and associated chemical and mineral analysis data for 36 sediment core and alluvium samples as well as Scanning Electron Microscopy analysis on select grains from magnetic and heavy mineral separates collected...
This dataset contains reflectance and transmission spectra of unexpanded and expanded vermiculite ore, and handpicked flakes of phlogopite, hydrobiotite, and vermiculite. These samples were collected from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, Llano, Texas; and South Africa. Spectra are identified as either reflectance or transmission in the alphanumeric file names and correlate to specpr record numbers designated in the manuscript figures in which they are shown. These transmission spectra were converted to absorbance in many of the figures. Spectra of talc, fibrous richterite amphibole, and serpentine are from well characterized samples from Feiser Mine, Ruby Mountains,...

map background search result map search result map Spectra Used in Figures Sediment bioassay toxicity data from the Upper Columbia River, Washington, 2013-2014 Contract laboratory results Contract laboratory results Sediment bioassay toxicity data from the Upper Columbia River, Washington, 2013-2014 Spectra Used in Figures