This dataset provides baseline concentrations (from 2014) of polycyclic aromatic hydrocarbon (PAH), other aromatic organic compounds, mercury (Hg), and trace metal concentrations in sediment and biota collected from two sites along an existing rail line used for coal transport in the Columbia River Gorge, Washington. For this study, aquatic surface sediments, aquatic insects, and juvenile fish were collected in 2014 from Horsethief Lake in Columbia Hills State Park and Steigerwald Lake National Wildlife Refuge (NWR), both located in close proximity to the rail line and within the Columbia River Gorge National Scenic Area. Samples were collected from two subsites in each area: one closer to the rail line and one farther from the rail line. Fish species collected for analysis included anadromous salmonids and resident yellow perch, sculpin, pumpkinseed, northern pikeminnow, and smallmouth bass.

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.

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.

Comma-separated values (.csv) file containing data related to mercury in biota collected from the Hells Canyon Reservoir Complex on the Snake River, Idaho and Oregon.

Comma-separated values (.csv) file containing data related to mercury in biota collected from the Hells Canyon Reservoir Complex on the Snake River, Idaho and Oregon.

Comma-separated values (.csv) file containing data related to mercury in fishes collected from Clear Lake, California.

Comma-separated values (.csv) file containing data related to mercury in fishes collected from Clear Lake, California.

These data represent a one-time synoptic survey of sampled soils, pavement dust, and stream sediment in 10 urban watersheds in three regions of the United States (Pacific Northwest, northeast, and southeast) to evaluate sources of sediment and two groups of common urban contaminants: polycyclic aromatic hydrocarbons (PAHs) and metals. Analyses of samples from six of the watersheds included fallout radionuclides to facilitate identification of sediment sources to the streams. Scripts used in R to test selected explanatory variables for the urban contaminants using Generalize Additive Models (GAMs) are included. The percentage of the watershed that was sealed pavement and the percentage of the sediment sample from pavement dust were used as explanatory variables in statistical models of PAH and metal concentrations in the streams. This child item includes four data files containing the metals and PAH concentration data, radionuclide activity data, and pavement mapping statistics; a data dictionary describing the attributes in each data file; R scripts; the associated input files used for the GAM modeling; and a data dictionary for the input files.

These data represent a one-time synoptic survey of sampled soils, pavement dust, and stream sediment in 10 urban watersheds in three regions of the United States (Pacific Northwest, northeast, and southeast) to evaluate sources of sediment and two groups of common urban contaminants: polycyclic aromatic hydrocarbons (PAHs) and metals. Analyses of samples from six of the watersheds included fallout radionuclides to facilitate identification of sediment sources to the streams. Scripts used in R to test selected explanatory variables for the urban contaminants using Generalize Additive Models (GAMs) are included. The percentage of the watershed that was sealed pavement and the percentage of the sediment sample from pavement dust were used as explanatory variables in statistical models of PAH and metal concentrations in the streams. This child item includes four data files containing the metals and PAH concentration data, radionuclide activity data, and pavement mapping statistics; a data dictionary describing the attributes in each data file; R scripts; the associated input files used for the GAM modeling; and a data dictionary for the input files.

This dataset consists of 262 variables which describe various known and suspected point and non-point sources of contaminants and endocrine disrupting compounds (EDCs) throughout the Chesapeake Bay Watershed. Contaminant data was summarized to the NHDPlus Version 2.1 catchment level (1:100K). Contaminant data summarized span a time range of 2001 to 2016 and include regulated facilities, pesticides, manure and biosolids application data, mercury deposition, animal feeding applications, septic systems, landfills, and land use and land cover. These data are presented in a comma separated file, which includes all variables summarized and the NHDPlus Version 2.1 FEATUREID field (also known as COMID). The FEATUREID field can be used to relate these summaries to the NHDPlus Version 2.1 data suite for mapping and other analytical purposes. Total (TOT) and Divergent (DIV) upstream summaries were generated using the NHDPlusV2 Catchment Attribute Allocation and Accumulation Tool (CA3TV2). Using this method, upstreams summaries are generated for 82,263 of the 83,637 NHDPlus catchments in the Chesapeake Bay Watershed. These data will be used to investigate source-sink linkages between contaminant sources, water quality issues, and impacted receptor populations (e.g., smallmouth bass) throughout the Bay Watershed. Information gained from this work may also be used to evaluate the success of mitigation activities and help to prioritize new locations for mitigation, implementation of best management practices, or habitat conservation actions.