Selenium, Arsenic, Cadmium data daily concentration for USGS stream sites. This dataset is associated with the following publication: Beyene, M., S. Leibowitz, C. Dunn, and K. Bladon. To Burn or Not to Burn: An Empirical Assessment of the Impacts of Wildfires and Prescribed Fires on Trace Element Concentrations in Western US Streams. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier BV, AMSTERDAM, NETHERLANDS, 863(10): 160731, (2023).

The dataset includes groundwater information for: water stable isotopes, As concentrations, Se concentrations, and spectroscopic scans. This dataset is associated with the following publication: Wilkin, R.T., T. Lee, D. Beak, R. Anderson, and B. Burns. Groundwater Co-Contaminant Behavior of Arsenic and Selenium at a Lead and Zinc Smelting Facility. APPLIED GEOCHEMISTRY. Elsevier Science Ltd, New York, NY, USA, 89: 255-264, (2018).

In response to the 2010 Fourmile Canyon fire near Boulder, Colorado, the U.S. Geological Survey collected data to support investigations into the magnitude and critical drivers of water-quality impairment after wildfire. We analyzed chemistry of stream water, sediment, wildfire ash, soil, dust, and mine waste for metals and other parameters in order to evaluate the effects of legacy mining and wildfire on stream chemistry in the Colorado Front Range, USA. This data release includes data that were published earlier (McCleskey et al., 2012; Murphy et al., 2018).

In response to the 2010 Fourmile Canyon fire near Boulder, Colorado, the U.S. Geological Survey collected data to support investigations into the magnitude and critical drivers of water-quality impairment after wildfire. We analyzed chemistry of stream water, sediment, wildfire ash, soil, dust, and mine waste for metals and other parameters in order to evaluate the effects of legacy mining and wildfire on stream chemistry in the Colorado Front Range, USA. This data release includes data that were published earlier (McCleskey et al., 2012; Murphy et al., 2018).

Legacy mine waste from the Clark Fork River in Western Montana has contributed 100 million tons of tailings into the watershed between 1880 and 1982 (E.D. Andrews, Longitudinal dispersion of metals in the Clark Fork River, Montana, Lewis Publishers, 1987). Tailings deposited along the floodplain, streambanks and river channel continue to contribute metal contaminated material into the river in the form of metal-enriched particulate matter or seston, comprising a mixture of organic and inorganic materials (J.N. Moore and S.N. Luoma, Hazardous wastes from large-scale metal extraction: A case study. Environmental Science and Technology, v.24:1278-1285, 1990). Metal enriched seston poses a dietary exposure risk to filter-feeding macroinvertebrates that entrap and ingest suspended materials as a primary food source. Suspended particulate material and dissolved and total recoverable water samples were collected along a metal contamination gradient in 2017 and 2018 in the Clark Fork River and analyzed for metal concentrations to include the highly toxic metals arsenic, cadmium, and copper. Concentrations of seston arsenic (As), cadmium (Cd), and copper (Cu) ranged from 20.7–242 ug As/g, 2.7–16.2 ug Cd/g, and 129–1260 ug Cu/g. Dissolved (filtered) stream water concentrations ranged from 3.5–21.7 ug As/L, 0.1–0.38 ug Cd/L, and 1.5–12.5 ug Cu/L. Total recoverable (unfiltered) water concentrations ranged from 2.7–22.8 ug As/L, 0.1–0.35 ug Cd/L, and 2.0–14.9 ug Cu/L. Data presented here represent metal concentrations in water and seston from a mining-impacted river and provide insight to potential exposure of toxic metals to resident filter-feeding aquatic invertebrates.

Legacy mine waste from the Clark Fork River in Western Montana has contributed 100 million tons of tailings into the watershed between 1880 and 1982 (E.D. Andrews, Longitudinal dispersion of metals in the Clark Fork River, Montana, Lewis Publishers, 1987). Tailings deposited along the floodplain, streambanks and river channel continue to contribute metal contaminated material into the river in the form of metal-enriched particulate matter or seston, comprising a mixture of organic and inorganic materials (J.N. Moore and S.N. Luoma, Hazardous wastes from large-scale metal extraction: A case study. Environmental Science and Technology, v.24:1278-1285, 1990). Metal enriched seston poses a dietary exposure risk to filter-feeding macroinvertebrates that entrap and ingest suspended materials as a primary food source. Suspended particulate material and dissolved and total recoverable water samples were collected along a metal contamination gradient in 2017 and 2018 in the Clark Fork River and analyzed for metal concentrations to include the highly toxic metals arsenic, cadmium, and copper. Concentrations of seston arsenic (As), cadmium (Cd), and copper (Cu) ranged from 20.7–242 ug As/g, 2.7–16.2 ug Cd/g, and 129–1260 ug Cu/g. Dissolved (filtered) stream water concentrations ranged from 3.5–21.7 ug As/L, 0.1–0.38 ug Cd/L, and 1.5–12.5 ug Cu/L. Total recoverable (unfiltered) water concentrations ranged from 2.7–22.8 ug As/L, 0.1–0.35 ug Cd/L, and 2.0–14.9 ug Cu/L. Data presented here represent metal concentrations in water and seston from a mining-impacted river and provide insight to potential exposure of toxic metals to resident filter-feeding aquatic invertebrates.

Long-term monitoring of stream-bed sediments reveals spatial and temporal trends in metal concentrations. Here we use concentration gradient “heat maps” as a visualization tool to report annual mean arsenic, cadmium and copper concentrations along a contamination gradient in the Clark Fork River (CFR) in Western Montana. The CFR has been heavily impacted by large-scale mining operations since the 19th century. Legacy mine waste and tailings have been deposited within the streambed, banks, and floodplains more than 200 kilometers downstream. Sieved sediment samples (<63µm) have been collected at 10 stations along a 200 kilometer contamination gradient annually since 1996. Ongoing remediation activities in the upper basin (60 Km) have reduced the tailings deposits along the flood plain and may account for the reduction of some metals in the upper stations. Arsenic concentrations ranged from 12-204 µg/g from 2003-2020. The highest concentrations were observed in 2003 at river Km 11 while the lowest concentrations in all years occurred in the most downstream reaches. Concentrations of cadmium (1996-2020) ranged from 1-11 µg/g with the highest in the most upstream reaches between 2000-2003. Temporal trends in copper (1996-2020) ranged from 125-2053 µg/g with the highest concentrations observed in the most upstream stations during the earlier years.

Long-term monitoring of stream-bed sediments reveals spatial and temporal trends in metal concentrations. Here we use concentration gradient “heat maps” as a visualization tool to report annual mean arsenic, cadmium and copper concentrations along a contamination gradient in the Clark Fork River (CFR) in Western Montana. The CFR has been heavily impacted by large-scale mining operations since the 19th century. Legacy mine waste and tailings have been deposited within the streambed, banks, and floodplains more than 200 kilometers downstream. Sieved sediment samples (<63µm) have been collected at 10 stations along a 200 kilometer contamination gradient annually since 1996. Ongoing remediation activities in the upper basin (60 Km) have reduced the tailings deposits along the flood plain and may account for the reduction of some metals in the upper stations. Arsenic concentrations ranged from 12-204 µg/g from 2003-2020. The highest concentrations were observed in 2003 at river Km 11 while the lowest concentrations in all years occurred in the most downstream reaches. Concentrations of cadmium (1996-2020) ranged from 1-11 µg/g with the highest in the most upstream reaches between 2000-2003. Temporal trends in copper (1996-2020) ranged from 125-2053 µg/g with the highest concentrations observed in the most upstream stations during the earlier years.