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Environmental risk assessment and decision-making strategies over the last several decades have become increasingly more sophisticated, information-intensive, and complex, including such approaches as expert judgment, cost-benefit analysis, and toxicological risk assessment. One tool that has been used to support environmental decision-making is comparative risk assessment (CRA), but CRA lacks a structured method for arriving at an optimal project alternative. Multi-criteria decision analysis (MCDA) provides better-supported techniques for the comparison of project alternatives based on decision matrices, and it also provides structured methods for the incorporation of project stakeholders' opinions in the ranking...
In the late 1800s, mills in the Washoe Lake area, Nevada, used elemental mercury to remove gold and silver from the ores of the Comstock deposit. Since that time, mercury contaminated waste has been distributed from Washoe Lake, down Steamboat Creek, and to the Truckee River. The creek has high mercury concentrations in both water and sediments, and continues to be a constant source of mercury to the Truckee River. The objective of this study was to determine concentrations of total and methyl mercury (MeHg) in surface sediments and characterize their spatial distribution in the Steamboat Creek watershed. Total mercury concentrations measured in channel and bank sediments did not decrease downstream, indicating...
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This tabular data set represents the percent of surficial materials compiled for two spatial components of the NHDPlus version 2 data suite (NHDPlusv2) for the conterminous United States; 1) individual reach catchments and 2) reach catchments accumulated upstream through the river network. This dataset can be linked to the NHDPlus version 2 data suite by the unique identifier COMID. The source data is the "Map database for surficial materials in the conterminous United States" produced by the United States Geological Survey (USGS, 2009). Units are percent. Surficial materials are defined as an unconsolidated blanket of sediments in which soils commonly are developed. These sediments generally were eroded from underlying...
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This data release contains the data used to interpret the origin of the shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes. The data include 1) lake sediment core data for age dating (cesium-137 and lead-210) for 12 lakes in Uzbekistan, 2) lake sediment core data for loss on ignition (LOI550)for determining organic carbon content of 12 lakes in Uzbekistan, 3) plant pollen occurrence and abundance from lake sediment cores for 6 lakes in Uzbekistan and 4) lake sediment core data for pesticide occurrence of DDT (dichlorodiphenyltrichloroethane) and its degradates and γ-HCH (gamma-hexachlorocyclohexane) for 12 lakes in Uzbekistan, The interpretation of these data will...
At the Naturita site in Colorado, USA, groundwaters were sampled and analyzed for chemical composition and by culture and culture-independent microbiological techniques. In addition, sediments were extracted with a dilute sodium carbonate solution to determine quantities of labile uranium within the sediments. Samples from the upgradient portion of the contaminated aquifer, where very little dissolved Fe(II) is found in the groundwater, have uranium content that is controlled by U(VI) adsorption and few metal-reducing bacteria are observed. In the extreme downgradient portion of the aquifer, where dissolved Fe(II) is observed, uranium content of the sediments includes significant quantities of reduced U(IV) and...
At the Naturita site in Colorado, USA, groundwaters were sampled and analyzed for chemical composition and by culture and culture-independent microbiological techniques. In addition, sediments were extracted with a dilute sodium carbonate solution to determine quantities of labile uranium within the sediments. Samples from the upgradient portion of the contaminated aquifer, where very little dissolved Fe(II) is found in the groundwater, have uranium content that is controlled by U(VI) adsorption and few metal-reducing bacteria are observed. In the extreme downgradient portion of the aquifer, where dissolved Fe(II) is observed, uranium content of the sediments includes significant quantities of reduced U(IV) and...
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This data release contains the data used to interpret the origin of the shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes. The data include 1) lake sediment core data for age dating (cesium-137 and lead-210) for 12 lakes in Uzbekistan, 2) lake sediment core data for loss on ignition (LOI550)for determining organic carbon content of 12 lakes in Uzbekistan, 3) plant pollen occurrence and abundance from lake sediment cores for 6 lakes in Uzbekistan and 4) lake sediment core data for pesticide occurrence of DDT (dichlorodiphenyltrichloroethane) and its degradates and γ-HCH (gamma-hexachlorocyclohexane) for 12 lakes in Uzbekistan, The interpretation of these data will...
Recent observations indicate that curious closed depressions in carbonate sediments overlying basement edifices are widespread in the equatorial Pacific. A possible mechanism for their creation is dissolution by fluids exiting basement vents from off-axis hydrothermal flow. Quantitative analysis based on the retrograde solubility of calcium carbonate and cooling of basement fluids during ascent provides an estimate for the dissolution capacity of the venting fluids. Comparison of the dissolution capacity and fluid flux with typical equatorial Pacific carbonate mass accumulation rates shows that this mechanism is feasible. By maintaining sediment-free basement outcrops, the process may promote widespread circulation...
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This data release contains the data used to interpret the origin of the shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes. The data include 1) lake sediment core data for age dating (cesium-137 and lead-210) for 12 lakes in Uzbekistan, 2) lake sediment core data for loss on ignition (LOI550)for determining organic carbon content of 12 lakes in Uzbekistan, 3) plant pollen occurrence and abundance from lake sediment cores for 6 lakes in Uzbekistan and 4) lake sediment core data for pesticide occurrence of DDT (dichlorodiphenyltrichloroethane) and its degradates and γ-HCH (gamma-hexachlorocyclohexane) for 12 lakes in Uzbekistan, The interpretation of these data will...
Dam removal is a potentially powerful tool for restoring riverine habitats and communities. However, the effectiveness of this tool is unknown because published data on the effects of dam removal on in-stream biota are lacking. We investigated the effects of a small dam removal on unionid mussels in Koshkonong Creek, Wisconsin (USA). Removal of the dam led to mortality both within the former impoundment and in downstream reaches. Within the former reservoir, mortality rates were extremely high (95%) due to des- iccation and exposure. Mussel densities in a bed 0.5 km downstream from the dam declined from 3.80 ± 0.56 mussels m)2 in fall 2000 immediately after dam removal to 2.60 ± 0.48 mussels m)2 by summer 2003....
Many wildlife species ingest soil while feeding, but ingestion rates are known for only a few species. Knowing ingestion rates may be important for studies of environmental contaminants. Wildlife may ingest soil deliberately, or incidentally, when they ingest soil-laden forage or animals that contain soil. We fed white-footed mice (Peromyscus leucopus) diets containing 0-15% soil to relate the dietary soil content to the acid-insoluble ash content of scat collected from the mice. The relation was described by an equation that required estimates of the percent acid-insoluble ash content of the diet, digestibility of the diet, and mineral content of soil. We collected scat from 28 wildlife species by capturing animals,...
Environmental risk assessment and decision-making strategies over the last several decades have become increasingly more sophisticated, information-intensive, and complex, including such approaches as expert judgment, cost-benefit analysis, and toxicological risk assessment. One tool that has been used to support environmental decision-making is comparative risk assessment (CRA), but CRA lacks a structured method for arriving at an optimal project alternative. Multi-criteria decision analysis (MCDA) provides better-supported techniques for the comparison of project alternatives based on decision matrices, and it also provides structured methods for the incorporation of project stakeholders' opinions in the ranking...
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A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska; careful treatment of such data may provide significant and revealing geochemical maps that may be used for landscape geochemistry, mineral resource exploration, and geoenvironmental investigations over large areas. To maximize the spatial density and extent of data coverage for statewide mapping of element distributions, we compiled and integrated analyses of more than 175,000 sediment and soil samples from three major, separate sources: the U.S. Geological Survey, the National Uranium Resource Evaluation program, and the Alaska Division of Geological & Geophysical Surveys geochemical databases. Various types of...
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This portion of the USGS data release presents sediment grain-size data from samples on the Elwha River delta, Washington, in February 2016 (USGS Field Activity Number 2016-608-FA). Surface sediment was collected at a total of 83 locations using a small ponar, or 'grab', sampler from the R/V Frontier in water depths between 1 and 17 m around the delta. An additional 18 samples were collected by hand at low tide. A handheld global satellite navigation system (GNSS) receiver was used to determine the locations of sediment samples. Grab samples that yielded less than 50 g of sediment were omitted from analysis and are classified as "no sample". The grain-size distributions of samples that yielded more than 50 g of...
A complex mixture of hydrocarbons is present in the recent sediment of the Monterey Bay National Marine Sanctuary. Eighteen samples from the continental shelf between San Francisco and Monterey contain aliphatic and aromatic hydrocarbons showing biological contributions from both marine and terrigenous sources, with the terrigenous indicators more pronounced near Monterey. Of particular interest, however, is a low-level background of petroleum-related compounds, including 28,30-bisnorhopane and 18α+β(H)-oleanane, which are characteristic of many crude oils from the Monterey Formation of California. Thus, the sediments are overprinted by a regional chemical signature which may be derived from eroded Monterey Formation...
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A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska; careful treatment of such data may provide significant and revealing geochemical maps that may be used for landscape geochemistry, mineral resource exploration, and geoenvironmental investigations over large areas. To maximize the spatial density and extent of data coverage for statewide mapping of element distributions, we compiled and integrated analyses of more than 175,000 sediment and soil samples from three major, separate sources: the U.S. Geological Survey, the National Uranium Resource Evaluation program, and the Alaska Division of Geological & Geophysical Surveys geochemical databases. Various types of...
In the late 1800s, mills in the Washoe Lake area, Nevada, used elemental mercury to remove gold and silver from the ores of the Comstock deposit. Since that time, mercury contaminated waste has been distributed from Washoe Lake, down Steamboat Creek, and to the Truckee River. The creek has high mercury concentrations in both water and sediments, and continues to be a constant source of mercury to the Truckee River. The objective of this study was to determine concentrations of total and methyl mercury (MeHg) in surface sediments and characterize their spatial distribution in the Steamboat Creek watershed. Total mercury concentrations measured in channel and bank sediments did not decrease downstream, indicating...
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This data release contains the data used to interpret the origin of the shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes. The data include 1) lake sediment core data for age dating (cesium-137 and lead-210) for 12 lakes in Uzbekistan, 2) lake sediment core data for loss on ignition (LOI550)for determining organic carbon content of 12 lakes in Uzbekistan, 3) plant pollen occurrence and abundance from lake sediment cores for 6 lakes in Uzbekistan and 4) lake sediment core data for pesticide occurrence of DDT (dichlorodiphenyltrichloroethane) and its degradates and γ-HCH (gamma-hexachlorocyclohexane) for 12 lakes in Uzbekistan, The interpretation of these data will...
Although ?70 dams have been decommissioned in Wisconsin over the past 30 y, little is known about the physical and ecological effects of dam removal on riverine ecosystems. The purpose of our study was to document changes in channel form and macroinvertebrate assemblages following the removal of a low-head, run-of-river dam from the Baraboo River,Wisconsin, in January 2000. We surveyed cross sections and collected benthic macroinvertebrate samples in 6 reaches (an upstream reference reach, reaches immediately above and below the dam that was to be removed, and sequential unimpounded and impounded reaches further downstream) in a multiple-dam sys- tem. Surveys were conducted in December 1999, before dam removal,...
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The Sediment-Contaminant Database for the Upper Mississippi River System contains information from a total of 3950 analyzed sediment samples, including 2697 from the Mississippi River, 440 from the Illinois River, and 813 from tributaries. These samples were collected during 1974 through 2000, with 262 samples from the 1970s, 2168 from the 1980s, 1518 from the 1990s, and 2 from the year 2000. The database contains data on metals, metalloids, nutrients, polynuclear aromatic hydrocarbons, insecticides, herbicides, fungicides, industrial compounds, sterols, petroleum-related compounds, and polychlorinated biphenyls in three types of samples: bed sediment (86.6% of the samples), sediment trap (1.8%), and pore water...
map background search result map search result map Sediment-Contaminant Database for the Upper Mississippi River System and Selected Tributaries (version 2) Data Supporting The Geochemical Atlas of Alaska, 2016 The Geochemical Atlas of Alaska, 2016 - Geochem Data Datasets for determining the origin of shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes Attributes for NHDPlus Version 2.1 Catchments and Modified Routing of Upstream Watersheds for the Conterminous United States: Soller Surficial Materials, 2009 Dataset of Lead-210 and Cesium-137 age dating Dataset of Loss on Ignition data Rosen et al JoPL Pollen Dataset Surface-sediment grain-size distributions from the Elwha River delta, Washington, February 2016 Surface-sediment grain-size distributions from the Elwha River delta, Washington, February 2016 Datasets for determining the origin of shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes Dataset of Lead-210 and Cesium-137 age dating Dataset of Loss on Ignition data Rosen et al JoPL Pollen Dataset Sediment-Contaminant Database for the Upper Mississippi River System and Selected Tributaries (version 2) Data Supporting The Geochemical Atlas of Alaska, 2016 Attributes for NHDPlus Version 2.1 Catchments and Modified Routing of Upstream Watersheds for the Conterminous United States: Soller Surficial Materials, 2009 The Geochemical Atlas of Alaska, 2016 - Geochem Data