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This data set includes results for hormone and pharmaceutical compounds analyzed in environmental and quality-control samples collected by the USGS National Water-Quality Assessment Project during 2013 through 2015 for a study of groundwater resources used for drinking-water supply across the United States. Hormone and pharmaceutical results are provided for environmental samples collected at 1,120 wells or springs; selected ancillary data, such as principal aquifer, well depth, and land-use information also are provided for the sampled sites. The types of quality-control samples included in this data set are blanks, matrix spikes, and replicates collected at field sites or field offices. Included in this data...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Cycle 3,
Drinking water,
Environmental Health,
Groundwater,
Hormones,
Water-quality data for groundwater samples collected from 4,824 sites between 1991 through 2018, and ancillary data and information on sampled wells and principal aquifers, were used to assess the occurrence and distribution of strontium in U.S. groundwater from 32 principal aquifers. This data release includes one tab-delimited text file detailing these data. Table: Chemical data from the U.S. Geological Survey National Water Information System and ancillary data considered for assessment of strontium concentration in U.S. groundwater.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Hydrology,
NAWQA,
USGS Science Data Catalog (SDC),
Water Quality,
cycle 3,
Groundwater-quality data were collected from 502 wells as part of the National Water-Quality Assessment Project of the U.S. Geological Survey National Water-Quality Project and are included in this data release. Most of the wells (500) were sampled from January through December 2015 and 2 of them were sampled in 2013. The data were collected from five types of well networks: principal aquifer study networks, which are used to assess the quality of groundwater used for public water supply; land-use study networks, which are used to assess land-use effects on shallow groundwater quality; major aquifer study networks, which are used to assess the quality of groundwater used for domestic supply; enhanced trends networks,...
This data set includes sample information and results for third-party performance assessment samples analyzed for hormones and pharmaceuticals during the same general time period as environmental samples collected by the National Water-Quality Assessment (NAWQA) Project for a study of groundwater resources used for drinking-water supply across the United States, 2013 through 2015. Hormone and pharmaceutical results are provided for spiked and unspiked samples submitted by the Quality Systems Branch (QSB) Organic Blind Sample Project (OBSP), providing information regarding analyte recovery and occurrence of false positive and false negative results. Included in this data release are the following data tables: Table...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Cycle 3,
Groundwater,
NAWQA,
National Water Quality Program,
USGS Science Data Catalog (SDC),
A boosted regression tree (BRT) model was developed to predict pH conditions in three-dimensions throughout the glacial aquifer system (GLAC) of the contiguous United States using pH measurements in samples from 18,258 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls pH and when coupled with long flow paths, results in the most alkaline conditions. Conversely, in areas where glacial sediments are thin and carbonate-poor, pH conditions remain acidic. At depths typical of drinking-water supplies, predicted pH > 7.5 – which is associated with arsenic mobilization – occurs more frequently...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Boosted regression trees,
Calcite saturation index,
Connecticut,
Geochemistry,
Geochemistry,
Samples for analysis were selected from 1) archived rotosonic cores drilled by the Minnesota Geological Survey and archived at the Lands and Minerals Drill Core Library, Minnesota Department of Natural Resources, Hibbing, Minnesota, USA; or b) freshly collected rotosonic cores, collected on-site at the time of coring. Cores in the sample archive are stored in wooden core-boxes in ambient air. Cores have supporting geology, stratigraphy, geochemistry, and hydrogeology data as published in County Geologic Atlases, Parts A and B, by the Minnesota Geological Survey (MGS) and the Minnesota Department of Natural Resources (MDNR); or in Regional Hydrogeologic Assessments, MGS. Included in this data release are: Core_Chem_Locations.pdf:...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Geochemistry,
Hydrology,
Minnesota,
USGS Science Data Catalog (SDC),
Water Quality,
Residence time distribution (RTD) is a critically important characteristic of groundwater flow systems; however, it cannot be measured directly. RTD can be inferred from tracer data with analytical models (few parameters) or with numerical models (many parameters). The second approach permits more variation in system properties but is used less frequently than the first because large-scale numerical models can be resource intensive. With the data and computer codes in this data release users can (1) reconstruct and run 115 General Simulation Models (GSMs) of groundwater flow, (2) calculate groundwater age metrics at selected GSM cells, (3) train a boosted regression tree model using the provided data, (4) predict...
Evaluating Decadal Changes in Groundwater Quality: Groundwater quality data were collected from 5,000 wells between 1988-2001 (first sampling event) by the U.S. Geological Survey’s National Water-Quality Assessment Project. Samples are collected in groups of 20-30 wells with similar characteristics called networks. About 1,500 of these wells in 67 networks were sampled about 10 years later between 2002-2012 (second sampling event) to evaluate decadal changes in groundwater quality. Between 2012 and 2014 (third sampling event), a subset of these networks has been sampled again, allowing additional results to be displayed on the web page: Decadal changes in groundwater quality. Changes to this web page are referred...
Groundwater-quality data were collected from 559 wells as part of the National Water-Quality Assessment Project of the U.S. Geological Survey National Water-Quality Program from January through December 2014. The data were collected from four types of well networks: principal aquifer study networks, which assess the quality of groundwater used for public water supply; land-use study networks, which assess land-use effects on shallow groundwater quality; major aquifer study networks, which assess the quality of groundwater used for domestic supply; and enhanced trends networks, which evaluate the time scales during which groundwater quality changes. Groundwater samples were analyzed for a large number of water-quality...
Categories: Data;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Hydrogeology,
NAWQA,
National Water Quality Program,
USGS Science Data Catalog (SDC),
United States,
This data release includes grids representing the depth and thickness of drinking-water withdrawal zones, polygons of hydrogeologic settings, an inventory of sources of well construction data, and summaries of data comparisons used to assess the depth of groundwater used for drinking-water supplies in the United States. Well construction data sources are documented in Table1_DataSources.xlsx. Data comparisons using the Mann-Whitney test to assess similarity between hydrogeologic settings were used to justify combining data where they were sparse (compare_neighbors_all_domestic.txt and compare_neighbors_all_public.txt). Water-supply-well depth varies geographically by water use and the type of well, which illustrates...
Categories: Data,
Data Release - Revised;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Cycle 3,
Hydrology,
NAWQA,
USGS Science Data Catalog (SDC),
United States,
Widespread nitrate contamination of groundwater in agricultural areas poses a major challenge to sustainable water resources. Efficient analysis of nitrate fluxes across large regions also remains difficult. This study introduces a method of characterizing nitrate transport processes continuously across regional unsaturated zones and groundwater based on surrogate, machine-learning metamodels of an N flux process-based model. The metamodels used boosted regression trees (BRTs) to relate mappable variables to parameters and outputs of a “vertical flux method” (VFM) applied in the Fox-Wolf-Peshtigo (FWP) area in Wisconsin. In this context, the metamodels are upscaling the VFM results throughout the region, and the...
Groundwater samples were collected from domestic and public-supply wells in the Eagle Ford study area in 2015–16, in the Fayetteville study area in 2015, and in the Haynesville study area in 2014–15. One sample of produced water was collected from a gas well in the Haynesville Shale in Rusk County, Texas in 2010, and 5 samples of produced water were collected from oil and condensate wells in the Eagle Ford Shale in Gonzales and Lavaca Counties, Texas in 2015. Groundwater samples were analyzed for major ions, nutrients, and trace elements; methane, methane H and C isotopic compositions, and C1-C5 gas composition; H and O isotopic composition of water; noble gas concentrations and isotopic compositions; tritium,...
Groundwater samples were collected from 60 public supply wells in the Colorado Plateaus principal aquifer. Water quality evaluations of groundwater for drinking water at public supply depths were made with the purpose of summarizing the current quality of source water (that is, untreated water) from public supply wells using two types of assessments; (1) status: an assessment that describes the current quality of the groundwater resource, and (2) understanding: an evaluation of the natural and human factors affecting the quality of groundwater, including an explanation of statistically significant associations between water quality and selected explanatory factors. To provide context for water-quality data, constituent...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Arizona,
Colorado,
Cycle 3,
Hydrology,
NAWQA,
This data set includes results for hormone and pharmaceutical compounds analyzed in laboratory quality-control samples associated with environmental samples collected by the National Water-Quality Assessment (NAWQA) Project during 2013 through 2015 for a study of groundwater resources used for drinking-water supply across the United States. Hormone and pharmaceutical results are provided for laboratory set blanks and reagent spikes analyzed during a time period that encompasses laboratory analysis of the environmental samples collected by NAWQA. Included in this data release are the following data tables: Table 1. Hormone results for laboratory set blanks, December 18, 2012 through March 7, 2016. Table 2. Pharmaceutical...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Cycle 3,
Drinking water,
Environmental Health,
Groundwater,
Hormones,
The ascii grids associated with this data release are model inputs representing the Central Valley aquifer, California, and predicted nitrate concentrations (as NO3-N, mg/L) at two depth zones associated with private and public drinking water supply wells, respectively. The model input and prediction grids are bound by the alluvial bed boundary that defines the Central Valley. The prediction grids were produced with Boosted Regression Tree (BRT) modeling methods within a statistical modeling framework using the statistical modeling software R (R Core Team, https://www.r-project.org/) and linear interpolation within Oasis Montaj software (Geosoft, version 9.0.2). The response variable was a set of nitrate concentrations...
Evaluating Decadal Changes in Groundwater Quality: Groundwater-quality data were collected from 5,000 wells between 1988-2001 (first decadal sampling event) by the National Water-Quality Assessment Project. Samples are collected in groups of 20-30 wells with similar characteristics called networks. About 1,500 of these wells in 67 networks were sampled again approximately 10 years later between 2002-2012 (second sampling event) to evaluate decadal changes in groundwater quality. Between 2012 and 2018 (third sampling event), a subset of these networks was sampled again, allowing additional results to be displayed on the web page: Decadal changes in groundwater quality (https://nawqatrends.wim.usgs.gov/decadal/)....
From October 2017 through September 2022, the National Water Quality Network (NWQN) monitored 110 surface-water river and stream sites and more than 1,800 groundwater wells for a large number of water-quality analytes, for which associated quality-control data and corresponding statistical summaries are included in this data release. The quality-control data—for samples that were collected in the field (at all 110 surface-water sites, 350 groundwater wells, and 16 quality-control-only sites), prepared in the laboratory, or prepared by a third party—can be used to assess the quality of environmental data collected by the NWQN through the estimation of bias and variability in reported results. The general analyte...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Hydrology,
NAWQA,
NWQN,
USGS Science Data Catalog (SDC),
United States,
Groundwater-quality data were collected from 983 wells as part of the National Water-Quality Assessment Project of the U.S. Geological Survey National Water-Quality Program and are included in this report. The data were collected from six types of well networks: principal aquifer study networks, which are used to assess the quality of groundwater used for public water supply; land-use study networks, which are used to assess land-use effects on shallow groundwater quality; major aquifer study networks, which are used to assess the quality of groundwater used for domestic supply; enhanced trends networks, which are used to evaluate the time scales during which groundwater quality changes; vertical flow-path study...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Cycle 3,
Domestic supply,
Groundwater,
Hydrology,
NAWQA,
Groundwater samples were collected and analyzed from 782 wells as part of the National Water-Quality Assessment Project of the U.S. Geological Survey National Water-Quality Program and the water-quality data and quality-control data are included in this data release. The samples were collected from three types of well networks: principal aquifer study networks, which are used to assess the quality of groundwater used for public water supply; land-use study networks, which are used to assess land-use effects on shallow groundwater quality, and major aquifer study networks, which are used to assess the quality of groundwater used for domestic supply. Groundwater samples were analyzed for a large number of water-quality...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Cycle 3,
Domestic supply,
Groundwater,
NAWQA,
Principal aquifer,
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