Ken Belitz (Former Employee)
Science and Products
Filter Total Items: 30
Data for Machine Learning Predictions of Nitrate in Groundwater Used for Drinking Supply in the Conterminous United States Data for Machine Learning Predictions of Nitrate in Groundwater Used for Drinking Supply in the Conterminous United States
A three-dimensional extreme gradient boosting (XGB) machine learning model was developed to predict the distribution of nitrate in groundwater across the conterminous United States (CONUS). Nitrate was predicted at a 1-square-kilometer (km) resolution for two drinking water zones, each of variable depth, one for domestic supply and one for public supply. The model used measured nitrate
Data Release for Evaluation of Six Methods for Correcting Bias in Estimates from Ensemble Tree Machine Learning Regression Models Data Release for Evaluation of Six Methods for Correcting Bias in Estimates from Ensemble Tree Machine Learning Regression Models
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)...
Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018 Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018
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 mg/L) and a Health-Based...
Datasets of Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January 2017 through December 2019 Datasets of Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January 2017 through December 2019
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...
Datasets from Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January through December 2016, and Previously Unpublished Data from 2013 to 2015 Datasets from Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January through December 2016, and Previously Unpublished Data from 2013 to 2015
Groundwater-quality data were collected from 648 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. Most of the wells (514) were sampled from January through December 2016 and 60 of them were sampled in 2013 and 74 in 2014. The data were collected from seven types of well networks...
National Multi Order Hydrologic Position (MOHP) Predictor Data for Groundwater and Groundwater-Quality Modeling National Multi Order Hydrologic Position (MOHP) Predictor Data for Groundwater and Groundwater-Quality Modeling
Multi Order Hydrologic Position (MOHP) raster datasets: Distance from Stream to Divide (DSD) and Lateral Position (LP) have been produced nationally for the 48 contiguous United States at a 30-meter resolution for stream orders 1 through 9. These data are available for testing as predictor variables for various regional and national groundwater-flow and groundwater-quality statistical...
Point data for four case studies related to testing of multi-order hydrologic position Point data for four case studies related to testing of multi-order hydrologic position
The location of a point (or pixel) within the conterminous U.S. can be assigned based on its position relative to the Nation's stream network. Two metrics are recognized: lateral position (LP) and distance from stream to divide (DSD). And given that a point can have different positions in different hydrologic orders the term multi-order hydrologic position (MOHP) is used to describe the...
Data for Assessing the Lead Solubility Potential of Untreated Groundwater of the United States Data for Assessing the Lead Solubility Potential of Untreated Groundwater of the United States
Groundwater chemistry data used for assessing the lead (Pb) solubility potential of untreated groundwater of the United States were compiled from the USGS National Water Information System (NWIS) database for groundwater sites sampled between January 1, 2000 and January 1, 2016. Two datasets were compiled: one dataset having 13,324 groundwater sites was used to assess Pb occurrence in...
Domestic well locations and populations served in the contiguous U.S.: datasets for decadal years 2000 and 2010 Domestic well locations and populations served in the contiguous U.S.: datasets for decadal years 2000 and 2010
The 1990 census was the last nationally consistent survey of a home’s source of water, and has not been surveyed since. The associated larger work presents a method for projecting the population dependent on domestic wells for years after 1990, using information from the 1990 census along with population data from subsequent censuses. The method is based on the “domestic ratio” at the...
Laboratory Quality-Control Data Associated with Groundwater Samples Collected for Hormones and Pharmaceuticals by the National Water-Quality Assessment Project in 2013-15 Laboratory Quality-Control Data Associated with Groundwater Samples Collected for Hormones and Pharmaceuticals by the National Water-Quality Assessment Project in 2013-15
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...
Environmental and Quality-Control Data Collected by the USGS National Water-Quality Assessment Project for Hormones and Pharmaceuticals in Groundwater Used as a Source of Drinking Water Across the United States, 2013-15 Environmental and Quality-Control Data Collected by the USGS National Water-Quality Assessment Project for Hormones and Pharmaceuticals in Groundwater Used as a Source of Drinking Water Across the United States, 2013-15
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...
Data for Elevated Manganese Concentrations in United States Groundwater, Role of Land Surface-Soil-Aquifer Connections Data for Elevated Manganese Concentrations in United States Groundwater, Role of Land Surface-Soil-Aquifer Connections
Chemical data from 43,334 wells were used to examine the role of land surface-soil-aquifer connections in producing elevated manganese concentrations (>300 microgram/L) in United States (U.S.) groundwater. Elevated manganese and dissolved organic carbon (DOC) concentrations were associated with shallow water tables and organic-carbon rich soils, suggesting soil-derived DOC supported...
Filter Total Items: 206
Predicting regional fluoride concentrations at public and domestic supply depths in basin-fill aquifers of the western United States using a random forest model Predicting regional fluoride concentrations at public and domestic supply depths in basin-fill aquifers of the western United States using a random forest model
A random forest regression (RFR) model was applied to over 12,000 wells with measured fluoride (F) concentrations in untreated groundwater to predict F concentrations at depths used for domestic and public supply in basin-fill aquifers of the western United States. The model relied on twenty-two regional-scale environmental and surficial predictor variables selected to represent factors...
Authors
Celia Z Rosecrans, Kenneth Belitz, Katherine Marie Ransom, Peter B. McMahon, Paul E. Stackelberg
Populations using public-supply groundwater in the conterminous U.S. 2010; Identifying the wells, hydrogeologic regions, and hydrogeologic mapping units Populations using public-supply groundwater in the conterminous U.S. 2010; Identifying the wells, hydrogeologic regions, and hydrogeologic mapping units
Most Americans receive their drinking water from publicly supplied sources, a large portion of it from groundwater. Mapping these populations consistently and at a high resolution is important for understanding where the resource is used and needs to be protected. The results show that 269 million people are supplied by public supply, 107 million are supplied by groundwater and 162...
Authors
Tyler D. Johnson, Kenneth Belitz, Leon J. Kauffman, Elise Watson, John T. Wilson
Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January 2017 through December 2019 Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January 2017 through December 2019
Groundwater-quality environmental 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...
Authors
James A. Kingsbury, Laura M. Bexfield, Terri Arnold, MaryLynn Musgrove, Melinda L. Erickson, James R. Degnan, Anthony J. Tesoriero, Bruce D. Lindsey, Kenneth Belitz
Evaluation of six methods for correcting bias in estimates from ensemble tree machine learning regression model Evaluation of six methods for correcting bias in estimates from ensemble tree machine learning regression model
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. Method performance was evaluated using four case...
Authors
Kenneth Belitz, Paul E. Stackelberg
Lithium in groundwater used for drinking-water supply in the United States Lithium in groundwater used for drinking-water supply in the United States
Lithium concentrations in untreated groundwater from 1464 public-supply wells and 1676 domestic-supply wells distributed across 33 principal aquifers in the United States were evaluated for spatial variations and possible explanatory factors. Concentrations nationwide ranged from
Authors
Bruce D. Lindsey, Kenneth Belitz, Charles A. Cravotta, Patricia Toccalino, Neil M. Dubrovsky
Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context
This is the first assessment of groundwater from public-supply wells across the United States to analyze for >100 pesticide degradates and to provide human-health context for degradates without benchmarks. Samples from 1204 wells in aquifers representing 70% of the volume pumped for drinking supply were analyzed for 109 pesticides (active ingredients) and 116 degradates. Among the 41% of...
Authors
Laura M. Bexfield, Kenneth Belitz, Bruce D. Lindsey, Patricia Toccalino, Lisa H. Nowell
Machine learning predictions of pH in the Glacial Aquifer System, Northern USA Machine learning predictions of pH in the Glacial Aquifer System, Northern USA
A boosted regression tree model was developed to predict pH conditions in three dimensions throughout the glacial aquifer system of the contiguous United States using pH measurements in samples from 18,386 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...
Authors
Paul E. Stackelberg, Kenneth Belitz, Craig J. Brown, Melinda L. Erickson, Sarah M. Elliott, Leon J. Kauffman, Katherine Marie Ransom, James E. Reddy
Geochemistry and age of groundwater in the Williston Basin, USA: Assessing potential effects of shale-oil production on groundwater quality Geochemistry and age of groundwater in the Williston Basin, USA: Assessing potential effects of shale-oil production on groundwater quality
Thirty water wells were sampled in 2018 to understand the geochemistry and age of groundwater in the Williston Basin and assess potential effects of shale-oil production from the Three Forks-Bakken petroleum system (TBPS) on groundwater quality. Two geochemical groups are identified using hierarchical cluster analysis. Group 1 represents the younger (median 4He = 21.49 × 10−8 cm3 STP/g)...
Authors
Peter B. McMahon, Joel M. Galloway, Andrew G. Hunt, Kenneth Belitz, Bryant Jurgens, Tyler D. Johnson
Quality of pesticide data for groundwater analyzed for the National Water-Quality Assessment Project, 2013–18 Quality of pesticide data for groundwater analyzed for the National Water-Quality Assessment Project, 2013–18
The National Water-Quality Assessment (NAWQA) Project of the U.S. Geological Survey (USGS) submitted nearly 1,900 samples collected from groundwater sites across the United States in 2013–18 for analysis of 225 pesticide compounds (pesticides and pesticide degradates, hereafter referred to as “pesticides”) by USGS National Water Quality Laboratory schedule 2437 (S2437). For the...
Authors
Laura M. Bexfield, Kenneth Belitz, Mark W. Sandstrom, Delicia Beaty, Laura Medalie, Bruce D. Lindsey, Lisa H. Nowell
Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January through December 2016, and previously unpublished data from 2013 to 2015 Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January through December 2016, and previously unpublished data from 2013 to 2015
Environmental groundwater-quality data were collected from 648 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. Most of the wells (514) were sampled from January through December 2016, and 60 of them were sampled in 2013 and 74 in 2014. The data were collected from seven types of...
Authors
Terri Arnold, Laura M. Bexfield, MaryLynn Musgrove, Melinda L. Erickson, James A. Kingsbury, James R. Degnan, Anthony J. Tesoriero, Justin T. Kulongoski, Kenneth Belitz
Fluoride occurrence in United States groundwater Fluoride occurrence in United States groundwater
Data from 38,105 wells were used to characterize fluoride (F) occurrence in untreated United States (U.S.) groundwater. For domestic wells (n = 11,032), water from which is generally not purposely fluoridated or monitored for quality, 10.9% of the samples have F concentrations >0.7 mg/L (U.S. Public Health Service recommended optimal F concentration in drinking water for preventing tooth...
Authors
Peter B. McMahon, Craig J. Brown, Tyler D. Johnson, Kenneth Belitz, Bruce D. Lindsey
Multiorder hydrologic position in the conterminous United States: A set of metrics in support of groundwater mapping at regional and national scales Multiorder hydrologic position in the conterminous United States: A set of metrics in support of groundwater mapping at regional and national scales
The location of a point on the landscape within a stream network (hydrologic position) can be an important predictive measure in hydrology. Hydrologic position is defined here by two metrics: lateral position and distance from stream to divide, both measured horizontally. Lateral position (dimensionless) is the relative position of a point between the stream and its watershed divide...
Authors
Kenneth Belitz, Richard B. Moore, Terri Arnold, Jennifer B. Sharpe, J. Jeffrey Starn
Science and Products
Filter Total Items: 30
Data for Machine Learning Predictions of Nitrate in Groundwater Used for Drinking Supply in the Conterminous United States Data for Machine Learning Predictions of Nitrate in Groundwater Used for Drinking Supply in the Conterminous United States
A three-dimensional extreme gradient boosting (XGB) machine learning model was developed to predict the distribution of nitrate in groundwater across the conterminous United States (CONUS). Nitrate was predicted at a 1-square-kilometer (km) resolution for two drinking water zones, each of variable depth, one for domestic supply and one for public supply. The model used measured nitrate
Data Release for Evaluation of Six Methods for Correcting Bias in Estimates from Ensemble Tree Machine Learning Regression Models Data Release for Evaluation of Six Methods for Correcting Bias in Estimates from Ensemble Tree Machine Learning Regression Models
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)...
Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018 Inorganic Constituent and Ancillary Data for Evaluation of Lithium in Groundwater in the United States, 1991-2018
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 mg/L) and a Health-Based...
Datasets of Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January 2017 through December 2019 Datasets of Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January 2017 through December 2019
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...
Datasets from Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January through December 2016, and Previously Unpublished Data from 2013 to 2015 Datasets from Groundwater-Quality and Select Quality-Control Data from the National Water-Quality Assessment Project, January through December 2016, and Previously Unpublished Data from 2013 to 2015
Groundwater-quality data were collected from 648 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. Most of the wells (514) were sampled from January through December 2016 and 60 of them were sampled in 2013 and 74 in 2014. The data were collected from seven types of well networks...
National Multi Order Hydrologic Position (MOHP) Predictor Data for Groundwater and Groundwater-Quality Modeling National Multi Order Hydrologic Position (MOHP) Predictor Data for Groundwater and Groundwater-Quality Modeling
Multi Order Hydrologic Position (MOHP) raster datasets: Distance from Stream to Divide (DSD) and Lateral Position (LP) have been produced nationally for the 48 contiguous United States at a 30-meter resolution for stream orders 1 through 9. These data are available for testing as predictor variables for various regional and national groundwater-flow and groundwater-quality statistical...
Point data for four case studies related to testing of multi-order hydrologic position Point data for four case studies related to testing of multi-order hydrologic position
The location of a point (or pixel) within the conterminous U.S. can be assigned based on its position relative to the Nation's stream network. Two metrics are recognized: lateral position (LP) and distance from stream to divide (DSD). And given that a point can have different positions in different hydrologic orders the term multi-order hydrologic position (MOHP) is used to describe the...
Data for Assessing the Lead Solubility Potential of Untreated Groundwater of the United States Data for Assessing the Lead Solubility Potential of Untreated Groundwater of the United States
Groundwater chemistry data used for assessing the lead (Pb) solubility potential of untreated groundwater of the United States were compiled from the USGS National Water Information System (NWIS) database for groundwater sites sampled between January 1, 2000 and January 1, 2016. Two datasets were compiled: one dataset having 13,324 groundwater sites was used to assess Pb occurrence in...
Domestic well locations and populations served in the contiguous U.S.: datasets for decadal years 2000 and 2010 Domestic well locations and populations served in the contiguous U.S.: datasets for decadal years 2000 and 2010
The 1990 census was the last nationally consistent survey of a home’s source of water, and has not been surveyed since. The associated larger work presents a method for projecting the population dependent on domestic wells for years after 1990, using information from the 1990 census along with population data from subsequent censuses. The method is based on the “domestic ratio” at the...
Laboratory Quality-Control Data Associated with Groundwater Samples Collected for Hormones and Pharmaceuticals by the National Water-Quality Assessment Project in 2013-15 Laboratory Quality-Control Data Associated with Groundwater Samples Collected for Hormones and Pharmaceuticals by the National Water-Quality Assessment Project in 2013-15
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...
Environmental and Quality-Control Data Collected by the USGS National Water-Quality Assessment Project for Hormones and Pharmaceuticals in Groundwater Used as a Source of Drinking Water Across the United States, 2013-15 Environmental and Quality-Control Data Collected by the USGS National Water-Quality Assessment Project for Hormones and Pharmaceuticals in Groundwater Used as a Source of Drinking Water Across the United States, 2013-15
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...
Data for Elevated Manganese Concentrations in United States Groundwater, Role of Land Surface-Soil-Aquifer Connections Data for Elevated Manganese Concentrations in United States Groundwater, Role of Land Surface-Soil-Aquifer Connections
Chemical data from 43,334 wells were used to examine the role of land surface-soil-aquifer connections in producing elevated manganese concentrations (>300 microgram/L) in United States (U.S.) groundwater. Elevated manganese and dissolved organic carbon (DOC) concentrations were associated with shallow water tables and organic-carbon rich soils, suggesting soil-derived DOC supported...
Filter Total Items: 206
Predicting regional fluoride concentrations at public and domestic supply depths in basin-fill aquifers of the western United States using a random forest model Predicting regional fluoride concentrations at public and domestic supply depths in basin-fill aquifers of the western United States using a random forest model
A random forest regression (RFR) model was applied to over 12,000 wells with measured fluoride (F) concentrations in untreated groundwater to predict F concentrations at depths used for domestic and public supply in basin-fill aquifers of the western United States. The model relied on twenty-two regional-scale environmental and surficial predictor variables selected to represent factors...
Authors
Celia Z Rosecrans, Kenneth Belitz, Katherine Marie Ransom, Peter B. McMahon, Paul E. Stackelberg
Populations using public-supply groundwater in the conterminous U.S. 2010; Identifying the wells, hydrogeologic regions, and hydrogeologic mapping units Populations using public-supply groundwater in the conterminous U.S. 2010; Identifying the wells, hydrogeologic regions, and hydrogeologic mapping units
Most Americans receive their drinking water from publicly supplied sources, a large portion of it from groundwater. Mapping these populations consistently and at a high resolution is important for understanding where the resource is used and needs to be protected. The results show that 269 million people are supplied by public supply, 107 million are supplied by groundwater and 162...
Authors
Tyler D. Johnson, Kenneth Belitz, Leon J. Kauffman, Elise Watson, John T. Wilson
Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January 2017 through December 2019 Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January 2017 through December 2019
Groundwater-quality environmental 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...
Authors
James A. Kingsbury, Laura M. Bexfield, Terri Arnold, MaryLynn Musgrove, Melinda L. Erickson, James R. Degnan, Anthony J. Tesoriero, Bruce D. Lindsey, Kenneth Belitz
Evaluation of six methods for correcting bias in estimates from ensemble tree machine learning regression model Evaluation of six methods for correcting bias in estimates from ensemble tree machine learning regression model
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. Method performance was evaluated using four case...
Authors
Kenneth Belitz, Paul E. Stackelberg
Lithium in groundwater used for drinking-water supply in the United States Lithium in groundwater used for drinking-water supply in the United States
Lithium concentrations in untreated groundwater from 1464 public-supply wells and 1676 domestic-supply wells distributed across 33 principal aquifers in the United States were evaluated for spatial variations and possible explanatory factors. Concentrations nationwide ranged from
Authors
Bruce D. Lindsey, Kenneth Belitz, Charles A. Cravotta, Patricia Toccalino, Neil M. Dubrovsky
Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context
This is the first assessment of groundwater from public-supply wells across the United States to analyze for >100 pesticide degradates and to provide human-health context for degradates without benchmarks. Samples from 1204 wells in aquifers representing 70% of the volume pumped for drinking supply were analyzed for 109 pesticides (active ingredients) and 116 degradates. Among the 41% of...
Authors
Laura M. Bexfield, Kenneth Belitz, Bruce D. Lindsey, Patricia Toccalino, Lisa H. Nowell
Machine learning predictions of pH in the Glacial Aquifer System, Northern USA Machine learning predictions of pH in the Glacial Aquifer System, Northern USA
A boosted regression tree model was developed to predict pH conditions in three dimensions throughout the glacial aquifer system of the contiguous United States using pH measurements in samples from 18,386 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...
Authors
Paul E. Stackelberg, Kenneth Belitz, Craig J. Brown, Melinda L. Erickson, Sarah M. Elliott, Leon J. Kauffman, Katherine Marie Ransom, James E. Reddy
Geochemistry and age of groundwater in the Williston Basin, USA: Assessing potential effects of shale-oil production on groundwater quality Geochemistry and age of groundwater in the Williston Basin, USA: Assessing potential effects of shale-oil production on groundwater quality
Thirty water wells were sampled in 2018 to understand the geochemistry and age of groundwater in the Williston Basin and assess potential effects of shale-oil production from the Three Forks-Bakken petroleum system (TBPS) on groundwater quality. Two geochemical groups are identified using hierarchical cluster analysis. Group 1 represents the younger (median 4He = 21.49 × 10−8 cm3 STP/g)...
Authors
Peter B. McMahon, Joel M. Galloway, Andrew G. Hunt, Kenneth Belitz, Bryant Jurgens, Tyler D. Johnson
Quality of pesticide data for groundwater analyzed for the National Water-Quality Assessment Project, 2013–18 Quality of pesticide data for groundwater analyzed for the National Water-Quality Assessment Project, 2013–18
The National Water-Quality Assessment (NAWQA) Project of the U.S. Geological Survey (USGS) submitted nearly 1,900 samples collected from groundwater sites across the United States in 2013–18 for analysis of 225 pesticide compounds (pesticides and pesticide degradates, hereafter referred to as “pesticides”) by USGS National Water Quality Laboratory schedule 2437 (S2437). For the...
Authors
Laura M. Bexfield, Kenneth Belitz, Mark W. Sandstrom, Delicia Beaty, Laura Medalie, Bruce D. Lindsey, Lisa H. Nowell
Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January through December 2016, and previously unpublished data from 2013 to 2015 Groundwater-quality and select quality-control data from the National Water-Quality Assessment Project, January through December 2016, and previously unpublished data from 2013 to 2015
Environmental groundwater-quality data were collected from 648 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. Most of the wells (514) were sampled from January through December 2016, and 60 of them were sampled in 2013 and 74 in 2014. The data were collected from seven types of...
Authors
Terri Arnold, Laura M. Bexfield, MaryLynn Musgrove, Melinda L. Erickson, James A. Kingsbury, James R. Degnan, Anthony J. Tesoriero, Justin T. Kulongoski, Kenneth Belitz
Fluoride occurrence in United States groundwater Fluoride occurrence in United States groundwater
Data from 38,105 wells were used to characterize fluoride (F) occurrence in untreated United States (U.S.) groundwater. For domestic wells (n = 11,032), water from which is generally not purposely fluoridated or monitored for quality, 10.9% of the samples have F concentrations >0.7 mg/L (U.S. Public Health Service recommended optimal F concentration in drinking water for preventing tooth...
Authors
Peter B. McMahon, Craig J. Brown, Tyler D. Johnson, Kenneth Belitz, Bruce D. Lindsey
Multiorder hydrologic position in the conterminous United States: A set of metrics in support of groundwater mapping at regional and national scales Multiorder hydrologic position in the conterminous United States: A set of metrics in support of groundwater mapping at regional and national scales
The location of a point on the landscape within a stream network (hydrologic position) can be an important predictive measure in hydrology. Hydrologic position is defined here by two metrics: lateral position and distance from stream to divide, both measured horizontally. Lateral position (dimensionless) is the relative position of a point between the stream and its watershed divide...
Authors
Kenneth Belitz, Richard B. Moore, Terri Arnold, Jennifer B. Sharpe, J. Jeffrey Starn
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government