This data release includes geochemical and fallout radionuclide data for suspended sediments and potential sediment source types for the Loutsenhizer Arroyo and Sunflower Drain watersheds in western Colorado. Suspended sediments were collected by passive samplers deployed in the stream channel of the watershed outlets during four study periods between August 2018 and August 2019. Potential sediment source type samples were collected in the watersheds in duplicate using compositing techniques that targeted the top 5 centimeters of soil. The four potential sediment source-types were: agricultural fields, rangeland, arroyo walls, and streambanks. Source type samples were wet sieved to less than (<) 63 microns (µm) to target the size fraction likely to be entrained in streamflow as suspended sediments. Geochemical analyses were conducted by AGAT Laboratories (Canada) and data are reported for concentrations of 42 elements along with total carbon, carbonate, and organic carbon. Selenium concentrations were measured by hydride generation atomic absorption spectroscopy. Fallout radionuclide analyses were conducted at the USGS St. Petersburg Coastal and Marine Science Center by gamma-ray spectrometry methods. Activity ratios for total lead-210 to radium-226 and ratios of radium-226 to uranium-238 are reported along with propagated uncertainty for the ratios.

These data provide beryllium-7 (7Be) and excess lead-210 (210Pbxs) activity for fine-grained, mobile, streambed sediment in the Black Creek, Indiana (IN) stream-channel network. This basin is monitored in cooperation with the Great Lakes Restoration Initiative (GLRI). During the period July 22-25, 2019 (summer low flow), the thickness and spatial extent of soft, mobile, fine-grained (mainly silt and clay) streambed sediment was inventoried and sampled along 150-meter (m) transects. A combination of stream corridor land-use distribution, valley type, channel slope, stream order (Strahler, 1957), and ecoregion (Omernik and Griffith, 2014) was used to select 30 rapid geomorphic assessment reaches using methods of Fitzpatrick and others (2016); twelve of these were sampled for sediment fingerprinting and fallout-radionuclide (FRN) analysis.

These data provide beryllium-7 (7Be) and excess lead-210 (210Pbxs) activity for fine-grained, mobile, streambed sediment in the Black Creek, Indiana (IN) stream-channel network. This basin is monitored in cooperation with the Great Lakes Restoration Initiative (GLRI). During the period July 22-25, 2019 (summer low flow), the thickness and spatial extent of soft, mobile, fine-grained (mainly silt and clay) streambed sediment was inventoried and sampled along 150-meter (m) transects. A combination of stream corridor land-use distribution, valley type, channel slope, stream order (Strahler, 1957), and ecoregion (Omernik and Griffith, 2014) was used to select 30 rapid geomorphic assessment reaches using methods of Fitzpatrick and others (2016); twelve of these were sampled for sediment fingerprinting and fallout-radionuclide (FRN) analysis.

This U.S. Geological Survey (USGS) data release contains data from stream water, groundwater, and soil samples collected in 2019 and 2020 in the North Quartz Creek watershed in central Colorado. Fourteen streambank wells were installed in pairs at seven locations in August 2020 to capture the emerging groundwater from the left bank and right banks (relative to downstream-facing direction) and a synoptic sampling campaign was conducted to quantify metal contributions to the stream. A continuous, instream injection of sodium bromide (NaBr) was initiated at the head of the 5 km study reach several days prior to the synoptic sampling campaign and maintained throughout the duration of the study. Bromide concentrations were subsequently used to determine streamflow in the primary study reach (upper 1.3 km) using the tracer-dilution method, and as an indicator of hydrologic connections between North Quartz Creek and subsurface water. Streamflow was quantified in a secondary study reach (lower 3.7 km) using data from a series of sodium chloride slug additions wherein specific conductivity readings were used as a surrogate for the tracer concentration. Surface water samples were collected along North Quartz Creek including inflows from the left (LBI) and right (RBI) banks. Soil and sediment samples were collected along the transport path from source material (natural weathering and mine tailings/mine drainage) to the stream.

This U.S. Geological Survey (USGS) data release contains data from stream water, groundwater, and soil samples collected in 2019 and 2020 in the North Quartz Creek watershed in central Colorado. Fourteen streambank wells were installed in pairs at seven locations in August 2020 to capture the emerging groundwater from the left bank and right banks (relative to downstream-facing direction) and a synoptic sampling campaign was conducted to quantify metal contributions to the stream. A continuous, instream injection of sodium bromide (NaBr) was initiated at the head of the 5 km study reach several days prior to the synoptic sampling campaign and maintained throughout the duration of the study. Bromide concentrations were subsequently used to determine streamflow in the primary study reach (upper 1.3 km) using the tracer-dilution method, and as an indicator of hydrologic connections between North Quartz Creek and subsurface water. Streamflow was quantified in a secondary study reach (lower 3.7 km) using data from a series of sodium chloride slug additions wherein specific conductivity readings were used as a surrogate for the tracer concentration. Surface water samples were collected along North Quartz Creek including inflows from the left (LBI) and right (RBI) banks. Soil and sediment samples were collected along the transport path from source material (natural weathering and mine tailings/mine drainage) to the stream.

This data release includes physical and chemical data for samples from upland sources, eroding banks, streambed deposits, and suspended sediment in the Medicine Creek watershed, Missouri and Iowa. Samples were collected from July 2020 to June 2022. Data include total nitrogen and carbon concentrations, particle size analysis, stable isotope ratios, and concentrations of 49 mineral elements. These data are used for sediment fingerprinting to apportion relative contribution of sources in target fluvial samples, especially differentiation between bank erosion and upland sources. Source samples included streambank samples and upland soil samples, which were grouped by land-use category: crop, pasture, or forested. Target samples included suspended sediment collected with passive samplers and bed material collected specifically from fine-grain depositional areas, if present, within a stream reach.

The geochemical data included here were generated as part of a Technical Assistance Agreement between the U.S. Geological Survey (USGS) and Rio Tinto Exploration based in Salt Lake City, Utah. Beginning in November of 2015, we began a project to reanalyze up to 60,000 archived sample splits originally collected as part of the National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) project from selected areas in Arizona, California, Idaho, Montana, Nevada, New Mexico, and Utah. A small amount (approximately 0.25 g) of sieved <75 micron sample material was retrieved from the USGS National Geochemical Sample Archive for geochemical analysis. These samples were analyzed for 51 elements by ALS Global laboratories using their ultra-trace four-acid-digestion dual-mode inductively coupled plasma mass spectrometry (ICPMS) (ALS ME-MS61L) method (Ag, Al, As, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, Ge, Hf, In, K, La, Li, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, Re, S, Sb, Sc, Se, Sn, Sr, Ta, Te, Th, Ti, Tl, U, V, W, Y, Zn, and Zr plus Au, Pt, and Pd). Blind geologic reference materials (GRM), blanks, and sample duplicates were inserted by the USGS into every job of 36 samples to ensure the quality of the data. The results from these quality control (QC) samples, along with QC samples inserted by the laboratory, were evaluated for every job by a QC Manager. Only data that passed these checks were approved for release. Samples with analytical results that failed to pass the QC checks were reanalyzed and re-evaluated before the data were approved for release. The archived sample splits came from the NURE program, which began in 1973 with a primary goal of identifying uranium resources in the U.S. As one of nine components of the NURE program, the HSSR project systematically sampled the U.S. between 1976 and 1980 under the direction of four U.S. Department of Energy (DOE) national laboratories. Although there was some collaboration, each DOE laboratory developed its own sample collection, analytical, and data management methodologies, and hired contractors to do much of the actual work. Initially, Lawrence Livermore Laboratory (LLL) was responsible for the western states of Arizona, California, Idaho, Nevada, Oregon, Utah, and Washington; Los Alamos Scientific Laboratory (LASL) was responsible for the Rocky Mountain States (Colorado, Montana, New Mexico, and Wyoming) as well as Alaska; the Oak Ridge Gaseous Diffusion Plant (ORGDP) was responsible for 12 central Plains and upper Great Lakes States; and Savannah River Laboratory (SRL) was responsible for the remaining 23 states along the Eastern Seaboard, lower Great Lakes, Appalachians, and Gulf Coast. However, by 1979 the areas of responsibility had changed from state lines to 2-degree quadrangle boundaries and SRL had taken over the responsibility for completing the seven western states formerly assigned to LLL. Thus, quadrangles in the western third of the U.S. were variously sampled and analyzed by LLL, LASL, and SRL. Due to the enormous number of samples collected by these laboratories, some were sent to ORGDP for additional chemical analyses (Information Systems Programs, 1985; Smith, 1997). Geochemical samples were collected from multiple sources (78 percent stream-, 8 percent lake-, and 2 percent spring-sediments, and 12 percent soils). Analytical methods differed between laboratories and evolved over time so that 29 single- and multi-element analytical procedures, or variations thereof, were used during the project. The NURE-HSSR sediment and soil database compiled by Smith (1997) provides analytical results for 54 different elements (Ag, Al, As, Au, B, Ba, Be, Bi, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, F, Fe, Hf, Hg, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Pt, Rb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Th, Ti, U, V, W, Y, Yb, Zn, and Zr). However, no sample was analyzed for more than 46 elements, some were analyzed for uranium

The geochemical data included here were generated as part of a Technical Assistance Agreement between the U.S. Geological Survey (USGS) and Rio Tinto Exploration based in Salt Lake City, Utah. Beginning in November of 2015, we began a project to reanalyze up to 60,000 archived sample splits originally collected as part of the National Uranium Resource Evaluation (NURE) Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) project from selected areas in Arizona, California, Idaho, Montana, Nevada, New Mexico, and Utah. A small amount (approximately 0.25 g) of sieved <75 micron sample material was retrieved from the USGS National Geochemical Sample Archive for geochemical analysis. These samples were analyzed for 51 elements by ALS Global laboratories using their ultra-trace four-acid-digestion dual-mode inductively coupled plasma mass spectrometry (ICPMS) (ALS ME-MS61L) method (Ag, Al, As, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Fe, Ga, Ge, Hf, In, K, La, Li, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, Re, S, Sb, Sc, Se, Sn, Sr, Ta, Te, Th, Ti, Tl, U, V, W, Y, Zn, and Zr plus Au, Pt, and Pd). Blind geologic reference materials (GRM), blanks, and sample duplicates were inserted by the USGS into every job of 36 samples to ensure the quality of the data. The results from these quality control (QC) samples, along with QC samples inserted by the laboratory, were evaluated for every job by a QC Manager. Only data that passed these checks were approved for release. Samples with analytical results that failed to pass the QC checks were reanalyzed and re-evaluated before the data were approved for release. The archived sample splits came from the NURE program, which began in 1973 with a primary goal of identifying uranium resources in the U.S. As one of nine components of the NURE program, the HSSR project systematically sampled the U.S. between 1976 and 1980 under the direction of four U.S. Department of Energy (DOE) national laboratories. Although there was some collaboration, each DOE laboratory developed its own sample collection, analytical, and data management methodologies, and hired contractors to do much of the actual work. Initially, Lawrence Livermore Laboratory (LLL) was responsible for the western states of Arizona, California, Idaho, Nevada, Oregon, Utah, and Washington; Los Alamos Scientific Laboratory (LASL) was responsible for the Rocky Mountain States (Colorado, Montana, New Mexico, and Wyoming) as well as Alaska; the Oak Ridge Gaseous Diffusion Plant (ORGDP) was responsible for 12 central Plains and upper Great Lakes States; and Savannah River Laboratory (SRL) was responsible for the remaining 23 states along the Eastern Seaboard, lower Great Lakes, Appalachians, and Gulf Coast. However, by 1979 the areas of responsibility had changed from state lines to 2-degree quadrangle boundaries and SRL had taken over the responsibility for completing the seven western states formerly assigned to LLL. Thus, quadrangles in the western third of the U.S. were variously sampled and analyzed by LLL, LASL, and SRL. Due to the enormous number of samples collected by these laboratories, some were sent to ORGDP for additional chemical analyses (Information Systems Programs, 1985; Smith, 1997). Geochemical samples were collected from multiple sources (78 percent stream-, 8 percent lake-, and 2 percent spring-sediments, and 12 percent soils). Analytical methods differed between laboratories and evolved over time so that 29 single- and multi-element analytical procedures, or variations thereof, were used during the project. The NURE-HSSR sediment and soil database compiled by Smith (1997) provides analytical results for 54 different elements (Ag, Al, As, Au, B, Ba, Be, Bi, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, F, Fe, Hf, Hg, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Pt, Rb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Th, Ti, U, V, W, Y, Yb, Zn, and Zr). However, no sample was analyzed for more than 46 elements, some were analyzed for uranium

Near-surface geophysical data from within the Bonita Peak Mining District in Silverton, Colorado, USA are presented. These data were collected in 2019. The data include fiber optic distributed temperature sensing (FO-DTS) and frequency domain electromagnetic induction (FDEM) data collected in and around roughly 1 km reaches of Cement Creek and California Gulch. Additional data, including ground penetrating radar (GPR) and self potential (SP), were gathered from a peatland that intercepts acid mine drainage from Mogul Mine into Cement Creek. The peatland is located off the eastern bank of Cement Creek in the northern portion of the reach surveyed with FO-DTS and FDEM. In 2021, an FO-DTS, FDEM, and magnetometer (MAG) dataset were collected along both banks of an approximate 3-4 km reach of the Animas River, spanning from Arrastra Gulch upstream to USGS gage 09358000.

Sediment traps were deployed in tributaries to the San Juan River during 2021 and 2022. These traps collected sediment during storm events that typically occur as monsoonal convective storms from June to September. Because of the rural nature of the watershed, sediment traps were collected every 3 weeks so the sediment collected is a composite of that time period. The date listed is the date the trap was collected. This dataset includes the chemical concentrations of the sediment samples. Major ions are reported in weight percentage, while all other elements are reported in parts per million. Samples were fused at 750°C with sodium peroxide and the fusion cake dissolved in a dilute nitric acid. The resulting solution was analyzed by ICP-OES and ICP-MS. This method was done to include all of the rare earth elements. Results from this method may differ slightly from the results in the 49-element analysis because of the differences in digestion procedure. The 60 element dataset includes aluminum, calcium, iron, potassium, magnesium, phosphorous, sulfur, silicon, titanium, silver, arsenic, boron, barium, beryllium, bismuth, cadmium, cerium, cobalt, chromium, cesium, copper, dysprosium, erbium, europium, gallium, gadolinium, germanium, hafnium, holmium, indium, lanthanum, lithium, lutetium, manganese, molybdenum, niobium, neodymium, nickel, lead, praseodymium, rubidium, antimony, scandium, selenium, samarium, tin, strontium, tantalum, terbium, tellurium, thorium, thallium, thulium, uranium, vanadium, tungsten, yttrium, ytterbium, zinc, and zircon.