Filters: partyWithName: U.S. Geological Survey (X) > partyWithName: Jennifer B Sharpe (X)
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Concentrations of inorganic constituents, dissolved organic carbon (DOC), tritium, per- and polyfluoroalkyl substances (PFAS), volatile organic compounds (VOCs), and pharmaceuticals were measured in groundwater samples collected from 254 wells in 2019 and 2020. Concentrations of inorganic constituents, DOC, VOCs, and pharmaceuticals were measured at the U.S. Geological Survey (USGS) National Water Quality Laboratory in Lakewood, Colorado. Concentrations of tritium were measured at the USGS Tritium Laboratory in Menlo Park, California. Concentrations of PFAS were measured at SGS Laboratory in Orlando, Florida. In addition, several geospatial parameters were determined, including: percentages of selected land uses...
Digital datasets were used to develop basin characteristics values that are used in multiple regression equations and tested for the use in predicting flow-duration curves (FDCs) in ungaged areas of Indiana. Several basin characteristics are easily derived from StreamStats basin delineations, such as basin area (https://streamstats.usgs.gov/ss/). Other basin characteristics require ancillary datasets as input. The data provided through this data release are those data that have been collected, tested, and ultimately selected as a basis for FDC development. These include PRISM 3-Month Average Precipitation, Thickness and Coarseness of Quaternary Sediments, and Soil Available Water Capacity. There are 6 continuous...
This data release documents nine Microsoft Excel tables that contain data for understanding groundwater ages in the Glacial aquifer system. Results for the three sample networks (PAS, principal aquifer study; MSS, modeling support study; FPS, flow path study) are described by three tables each: dissolved gas modeling results, environmental tracer concentrations (tritium, tritiogenic helium-3, sulfur hexafluoride, carbon-14, and radiogenic helium-4), and results for the mean age and age distribution. Tables are labeled by network and data type (as described below) separated by an underscore (_). For example, dissolved gas modeling results from the PAS network is label ‘PAS_NGmodel’. Dissolved gas modeling results...
This data release documents eight Microsoft Excel tables; four which contain data for understanding groundwater ages in the South East Coastal Plain (SECP), Coastal Lowlands (CLOW) and Mississippi Embayment and Texas Coastal Uplands (METX) aquifer systems and four that describe the data fields. Results described include dissolved gas modeling results, environmental tracer concentrations (tritium, tritiogenic helium-3, sulfur hexafluoride, and radiogenic helium-4), mean age and age distribution, and carbon-14 geochmical modeling results Dissolved gas modeling results (DGmodel) contains detailed information on the calibration of dissolved gas models to dissolved gas concentrations (neon, argon, krypton, xenon, and...
This data release contains input data used in model development and TIF raster files used to predict the probability of low dissolved oxygen (DO) and high dissolved iron (Fe) in groundwater within the glacial aquifer system in the northern continental United States. Input data include measured DO and Fe concentrations at groundwater wells, and associated predictor variable data. The probability of low DO and high Fe was predicted using boosted regression tree methods using the gbm package in R (v. 4.0.0) in RStudio (v. 1.2.5042). The response variables for individual models were the occurrence of: (1) DO ≤0.5 mg/L, (2) DO ≤2 mg/L, and (3) Fe >100 µg/L. Water-quality data were compiled from three sources, as described...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Connecticut,
Geochemistry,
Hydrology,
Idaho,
Illinois,
Continuous monitoring and discrete water-quality sampling were coupled in a karst aquifer to assess drivers and timescales of water-quality change. Water-quality data included environmental tracers of groundwater age (tritium [3H], tritiogenic helium-3 [3He-trit], sulfur hexafluoride [SF6], carbon-14 [14C], and radiogenic helium-4 [4He-rad]). All water quality data is available from the U.S. Geological Survey NWIS database (U.S. Geological Survey, 2019). Groundwater ages were estimated by calibration of environmental tracers to lumped parameter models of groundwater age for multiple samples collected at six groundwater wells using the program TracerLPM (Jurgens and others, 2012). The final estimates for mean groundwater...
This data release consists of data (in four tables) for assessing the time scales of arsenic variability in three production wells in New Hampshire; tables that describe the data fields in the data tables are also included in the data release. High-frequency (every 5 to 15 minutes) and bi-monthly water-quality monitoring of a bedrock-aquifer domestic well (425651070573701), a bedrock-aquifer public-supply well (425400070545401), and a glacial-aquifer public-supply well (425311070535801) was completed between 2014 and 2018. Concentrations of arsenic and other geochemical constituents and dissolved gases, as tracers of groundwater age, were measured on a bimonthly basis; physicochemical data, including specific conductance,...
The U.S. Geological Survey (USGS), in cooperation with the Illinois Center for Transportation and the Illinois Department of Transportation, prepared hydro-conditioned geographic information systems (GIS) layers for use in the Illinois StreamStats application. These data were used to delineate drainage basins and compute basin characteristics for updated peak flow and flow duration regression equations for Illinois. This dataset consists of raster grid files for elevation (dem), flow accumulation (fac), flow direction (fdr), and stream definition (str900) for each 8-digit Hydrologic Unit Code (HUC) area in Illinois merged into a single dataset. There are 51 full or partial HUC 8s represented by this data set: 04040002,...
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...
Lithium concentrations in untreated groundwater from 1,464 public-supply wells, 1,676 domestic-supply wells, and 1,560 monitoring wells distributed across 33 principal aquifers in the United States were evaluated for spatial variations and possible explanatory factors. For context, lithium concentrations are compared to a drinking-water only threshold (60 micrograms per liter) and a Health-Based Screening Level (HBSL, 10 micrograms per liter). These thresholds were exceeded in 9% and 45% of samples from public-supply wells and in 6% and 37% from domestic-supply wells, respectively. Exceedances were most frequent for arid regions and older groundwater. Groundwater lithium concentrations were highest in unconsolidated...
Categories: Data;
Tags: Hydrology,
NAWQA,
USGS Science Data Catalog (SDC),
United States,
Water Quality,
Categorical classification of groundwater age based on concentrations of tritium (3H) in groundwater can provide useful information for the assessment and understanding of groundwater resources. These data present a three-part groundwater age classification system for the continental United States based on tritium thresholds that vary in space and time: modern (recharged after 1952), if the measured value is larger than an upper threshold; premodern (recharged prior to 1953) if the measured value is smaller than a lower threshold; or mixed if the measured value is between the two thresholds. Inclusion of spatially-varying that vary geographically on the basis of the location of the sample rather than a single threshold...
Evaluating Decadal Changes in Groundwater Quality: Groundwater quality data were collected from 5,000 wells between 1988-2001 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 about 10 years later between 2002-2012 (second sampling event) to evaluate decadal changes in groundwater quality. Between 2012 and 2016 (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. This is the third iteration of data added to the website, so this data release is referred...
The U.S. Geological Survey (USGS), in cooperation with the Cook County Bureau of Technology (BOT), prioritized waterbodies (lakes, rivers, and canals) of interest within Cook County to survey in 2022. These surveys describe the bathymetry and basic water-quality conditions observed, and could be used by the BOT to assist with resource management decisions and uses, as well as build an inventory that could be shared with other local governmental agencies. Waterbodies surveyed in 2022 and included in this data release are: Arrowhead Lake, Axehead Lake, Baker's Lake, Belly Deep Slough, Bode Lake North, Bode Lake South, Bull Frog Lake, Busse Lake Main Pool, Busse Lake North Pool, Busse Lake South Pool, Busse Woods...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Chicago,
Cook County,
Environmental Health,
Geography,
Hydrology,
Three wells in New Hampshire were sampled bimonthly over three years to evaluate the temporal variability of arsenic concentrations and groundwater age. All samples had measurable concentrations of arsenic throughout the entire sampling period and concentrations in individual wells varied, on average, by more than 7 µg/L. High arsenic concentrations (>10 µg/L) were measured in wells KFW-87 and SGW-93, consistent with the high pH and low dissolved oxygen typically found in bedrock wells. Lower arsenic concentrations (< 10 µg/L) at well SGW-65 were consistent with lower pH typical of the glacial aquifer. The well producing the oldest water, public bedrock well SGW-93, was not the well with the highest arsenic concentrations;...
This data release includes tables and plots of results for pesticide compounds (pesticides and degradates) analyzed in groundwater samples collected by the USGS National Water-Quality Assessment Project during water years 2013-18 and in associated quality-control samples that are used to assess the quality of the reported pesticide results. All samples were analyzed by the USGS National Water Quality Laboratory (NWQL) using laboratory schedule 2437. The table of groundwater data includes pesticide results as reported by the laboratory, along with results that represent the application of censoring levels at the 90-percent upper confidence limit of the 95th percentile of laboratory blank concentrations determined...
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 2020 (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/)....
Ensemble-tree machine learning (ML) regression models can be prone to systematic bias: small values are overestimated and large values are underestimated. Additional bias can be introduced if the dependent variable is a transform of the original data. Six methods were evaluated for their ability to correct systematic and introduced bias: (1) empirical distribution matching (EDM); (2) regression of observed on estimated values (ROE); (3) linear transfer function (LTF); (4) linear equation based on Z-score transform (ZZ); (5) second machine learning model used to estimate residuals (ML2-RES); and (6) Duan smearing estimate applied after ROE is implemented (ROE-Duan). The performance of the methods was evaluated using...
Categories: Data;
Tags: Central Valley, California,
Glacial aquifer system,
Mississippi Embayment,
NAWQA,
North Atlantic Coastal Plain,
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,
This dataset provides analytical and other data in support of an analysis of lead and manganese in untreated drinking water from Atlantic and Gulf Coastal Plain aquifers, eastern United States. The occurrence of dissolved lead and manganese in sampled groundwater, prior to its distribution or treatment, is related to the potential presence of source minerals and specific environmental factors including hydrologic position along the flow path, water-rock interactions, and associated geochemical conditions such as pH and dissolved oxygen (DO) concentrations. A DO/pH framework is proposed as a screening tool for evaluating risk of elevated lead or manganese, based on the occurrence of elevated lead and manganese concentrations...
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