Filters: Tags: Arsenic (X) > Date Range: {"choice":"year"} (X) > partyWithName: U.S. Geological Survey (X)
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These data were collected using field portable (handheld) X-ray fluorescence (pXRF) equipped with a 4-watt Ta/Au X-ray tube. Samples of surficial alluvium, rock, and archived core material from existing auger- or sonic-drilled monitoring wells in Hinkley Valley and the adjoining Water Valley, 140 kilometers (km) northeast of Los Angeles, California, were measured as part of an investigation of naturally-occurring and anthropogenic hexavalent chromium, Cr(VI), concentrations in local groundwater. Surficial alluvium samples were collected from small stream channels draining distinct geologic units, or from previously mapped river deposits, and generally consisted of silt, sand, and granules to small pebbles. Twigs...
A series of three-dimensional, hypothetical, groundwater models (MODFLOW-NWT) were developed to investigate the effects of a variety of factors on the flow of arsenic-containing water into a well. The well is of novel design with a constructed aquifer providing storage. The models simulate a hillslope with till overlying a fractured bedrock aquifer as is common in New England. Backwards particle tracking using MODPATH was used to track the particles from the constructed aquifer to the recharge location. A new program, EndPoint Analyzer, was used to determine the fraction of the flow that passed through the bedrock. The bedrock is assumed to be the source of arsenic contamination so the fraction of the flow passing...
These data were collected using field portable (handheld) X-ray fluorescence (pXRF) equipped with a 4-watt Ta/Au X-ray tube. Samples of surficial alluvium, rock, and archived drill cuttings from monitoring wells in the western part of the Mojave Desert, 60 to 210 kilometers (km) northeast of Los Angeles, California, were measured using as part of an investigation of naturally-occurring trace elements dissolved in groundwater. Surficial alluvium samples were collected from small stream channels draining distinct geologic units, or from previously mapped river deposits, and generally consisted of silt, sand, and granules to small pebbles. Twigs and other detritus were removed prior to measurement. Rocks were collected...
Over the past 15 years Douglas County, NV has removed production wells in northern Carson Valley from use due to relatively high arsenic concentrations (Carl Ruschmeyer, January 2013, Douglas County Public Works Director, verbal communication). To maintain the supply of water to the public, the town of Minden has been providing water to Douglas County and Carson City. Due to the projected increases in municipal demand, water resource managers are concerned that increasing pumping rates from wells in Minden may change groundwater chemistry and degrade the resource by potentially drawing in arsenic enriched water. Naturally occurring arsenic is one of the most common contaminants in groundwater in the western United...
These data were collected using field portable (handheld) X-ray fluorescence (pXRF) equipped with a 4-watt Ta/Au X-ray tube on two National Institute of Standards and Technology (NIST) certified standard reference materials 2710a and 2711a, a U.S. Geological Survey (USGS) certified standard reference material BHVO-2, and a silicon dioxide blank. These quality assurance data were collected as part of detailed pXRF studies in Hinkley and Water Valleys, 140 kilometers (km) northeast of Los Angeles, California, and as part of a regional geochemical survey in the western Mojave Desert, between 60 to 210 km northeast of Los Angeles. Measurements on National Institute of Standards and Technology (NIST) and U.S. Geological...
These data were released prior to the October 1, 2016 effective date for the USGS’s policy dictating the review, approval, and release of scientific data as referenced in USGS Survey Manual Chapter 502.8 Fundamental Science Practices: Review and Approval of Scientific Data for Release. The map graphic image at https://www.sciencebase.gov/catalog/file/get/63140561d34e36012efa2b7f?name=arsenic_map.png illustrates arsenic values, in micrograms per liter, for groundwater samples from about 31,000 wells and springs in 49 states compiled by the United States Geological Survey (USGS). The map graphic illustrates an updated version of figure 1 from Ryker (2001). Cited Reference: Ryker, S.J., Nov. 2001, Mapping arsenic...
Categories: pre-SM502.8;
Tags: Arsenic,
NSDI,
USGS Science Data Catalog (SDC),
United States,
environment,
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