Peter B McMahon (Former Employee)
Science and Products
Filter Total Items: 14
Quality-Control Data for Volatile Organic Compounds and Environmental Sulfur-Hexafluoride Data for Groundwater Samples from the Williston Basin, USA Quality-Control Data for Volatile Organic Compounds and Environmental Sulfur-Hexafluoride Data for Groundwater Samples from the Williston Basin, USA
In 2018, groundwater samples were collected from aquifers in the Williston Basin in parts of eastern Montana, western North Dakota, and northwestern South Dakota. This dataset includes quality-control data for volatile organic compounds that include data for source-solution blanks and field blanks. The dataset also includes data for sulfur hexafluoride in environmental samples of...
Data for Fluoride Occurrence in United States Groundwater Data for Fluoride Occurrence in United States Groundwater
Data from 38,105 wells were used to characterize fluoride occurrence in untreated United States groundwater. The data were retrieved from the U.S. Geological Survey (USGS) National Water Information System (NWIS). Groundwater samples were collected from 1988 to 2017 in the conterminous United States. Data for groundwater included in this dataset are pH, water temperature, and...
Data Release for Hydrocarbons in Upland Groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA Data Release for Hydrocarbons in Upland Groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA
Water samples from 50 domestic wells located 1 km (distal) from shale-gas wells in upland areas of the Marcellus Shale region were analyzed for chemical, isotopic and groundwater-age tracers. Uplands were targeted because natural mixing with brine and hydrocarbons from deep formations is less common in those areas compared to valleys. Methane (CH4) -isotope and pre-drill CH4 data...
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...
Well characteristics, water quality and age-date tracer data for wells along two regional flow paths in the Memphis aquifer, southwest Tennessee Well characteristics, water quality and age-date tracer data for wells along two regional flow paths in the Memphis aquifer, southwest Tennessee
In 2013, water-quality and age-date tracer samples were collected at wells located along two flow paths in the Memphis aquifer, southwest Tennessee, as part of the National Water Quality Assessment (NAWQA) Project of the National Water-Quality Program to better understand the vulnerability of the aquifer to contamination.. Each flow path began in the aquifer outcrop area (shallow well...
Data from Methane in Aquifers Used for Public Supply in the United States Data from Methane in Aquifers Used for Public Supply in the United States
In 2013 to 2015, 833 public supply wells in 15 Principal aquifers in the United States were sampled to identify which aquifers contained high methane concentrations (greater than 1 mg/L) and determine the geologic, hydrologic, and geochemical conditions associated with high concentrations. This study represents the first national assessment of methane in aquifers used for public supply...
Filter Total Items: 118
Groundwater quality near the Montebello Oil Field, Los Angeles County, California Groundwater quality near the Montebello Oil Field, Los Angeles County, California
Groundwater quality and potential sources and migration pathways of chemical constituents associated with hydrocarbon-bearing formations were assessed by the U.S. Geological Survey for the California State Water Resources Control Board Oil and Gas Regional Monitoring Program (RMP). Groundwater samples were collected as part of the RMP from 21 preexisting wells used for public supply...
Authors
Jennifer Stanton, Michael Land, Matthew Landon, David Shimabukuro, Peter McMahon, Tracy Davis, Andrew Hunt, Theron A. Sowers
Quality of groundwater used for public supply in the continental United States: A comprehensive assessment Quality of groundwater used for public supply in the continental United States: A comprehensive assessment
The presence of contaminants in a source water can constrain its suitability for drinking. The quality of groundwater used for public supply was assessed in 25 principal aquifers (PAs) that account for 84% of groundwater pumped for public supply in the U.S. (89.6 million people on a proportional basis). Each PA was sampled across its lateral extent using an equal-area grid, typically...
Authors
Kenneth Belitz, Miranda Fram, Bruce Lindsey, Paul Stackelberg, Laura Bexfield, Tyler D. Johnson, Bryant Jurgens, James Kingsbury, Peter McMahon, Neil Dubrovsky
Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination
The distribution of groundwater age is useful for evaluating the susceptibility and sustainability of groundwater resources. Here, we compute the aquifer-scale cumulative distribution function to characterize the age distribution for 21 Principal Aquifers that account for ~80% of public-supply pumping in the United States. The aquifer-scale cumulative distribution function for each...
Authors
Bryant Jurgens, Kirsten Faulkner, Peter McMahon, Andrew Hunt, Gerolamo Casile, Megan Young, Kenneth Belitz
Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA
Study region Santa Barbara County, California, USA.Study focus To analyze a wide array of newly collected chemical, isotopic, dissolved gas, and age dating tracers in conjunction with historical data from groundwater and oil wells to determine if water and/or thermogenic gas from oil-bearing formations have mixed with groundwater in the Orcutt Oil Field and surrounding area.New...
Authors
Robert Anders, Matthew Landon, Peter McMahon, Justin Kulongoski, Andrew G. Hunt, Tracy Davis
Perfluoroalkyl and polyfluoroalkyl substances in groundwater used as a source of drinking water in the eastern United States Perfluoroalkyl and polyfluoroalkyl substances in groundwater used as a source of drinking water in the eastern United States
In 2019, 254 samples were collected from five aquifer systems to evaluate per- and polyfluoroalkyl substance (PFAS) occurrence in groundwater used as a source of drinking water in the eastern United States. The samples were analyzed for 24 PFAS, major ions, nutrients, trace elements, dissolved organic carbon (DOC), volatile organic compounds (VOCs), pharmaceuticals, and tritium. Fourteen...
Authors
Peter McMahon, Andrea Tokranov, Laura Bexfield, Bruce Lindsey, Tyler D. Johnson, Melissa Lombard, Elise Watson
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 Rosecrans, Kenneth Belitz, Katherine Ransom, Peter McMahon, Paul Stackelberg
Science and Products
Filter Total Items: 14
Quality-Control Data for Volatile Organic Compounds and Environmental Sulfur-Hexafluoride Data for Groundwater Samples from the Williston Basin, USA Quality-Control Data for Volatile Organic Compounds and Environmental Sulfur-Hexafluoride Data for Groundwater Samples from the Williston Basin, USA
In 2018, groundwater samples were collected from aquifers in the Williston Basin in parts of eastern Montana, western North Dakota, and northwestern South Dakota. This dataset includes quality-control data for volatile organic compounds that include data for source-solution blanks and field blanks. The dataset also includes data for sulfur hexafluoride in environmental samples of...
Data for Fluoride Occurrence in United States Groundwater Data for Fluoride Occurrence in United States Groundwater
Data from 38,105 wells were used to characterize fluoride occurrence in untreated United States groundwater. The data were retrieved from the U.S. Geological Survey (USGS) National Water Information System (NWIS). Groundwater samples were collected from 1988 to 2017 in the conterminous United States. Data for groundwater included in this dataset are pH, water temperature, and...
Data Release for Hydrocarbons in Upland Groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA Data Release for Hydrocarbons in Upland Groundwater, Marcellus Shale Region, Northeastern Pennsylvania and Southern New York, USA
Water samples from 50 domestic wells located 1 km (distal) from shale-gas wells in upland areas of the Marcellus Shale region were analyzed for chemical, isotopic and groundwater-age tracers. Uplands were targeted because natural mixing with brine and hydrocarbons from deep formations is less common in those areas compared to valleys. Methane (CH4) -isotope and pre-drill CH4 data...
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...
Well characteristics, water quality and age-date tracer data for wells along two regional flow paths in the Memphis aquifer, southwest Tennessee Well characteristics, water quality and age-date tracer data for wells along two regional flow paths in the Memphis aquifer, southwest Tennessee
In 2013, water-quality and age-date tracer samples were collected at wells located along two flow paths in the Memphis aquifer, southwest Tennessee, as part of the National Water Quality Assessment (NAWQA) Project of the National Water-Quality Program to better understand the vulnerability of the aquifer to contamination.. Each flow path began in the aquifer outcrop area (shallow well...
Data from Methane in Aquifers Used for Public Supply in the United States Data from Methane in Aquifers Used for Public Supply in the United States
In 2013 to 2015, 833 public supply wells in 15 Principal aquifers in the United States were sampled to identify which aquifers contained high methane concentrations (greater than 1 mg/L) and determine the geologic, hydrologic, and geochemical conditions associated with high concentrations. This study represents the first national assessment of methane in aquifers used for public supply...
Filter Total Items: 118
Groundwater quality near the Montebello Oil Field, Los Angeles County, California Groundwater quality near the Montebello Oil Field, Los Angeles County, California
Groundwater quality and potential sources and migration pathways of chemical constituents associated with hydrocarbon-bearing formations were assessed by the U.S. Geological Survey for the California State Water Resources Control Board Oil and Gas Regional Monitoring Program (RMP). Groundwater samples were collected as part of the RMP from 21 preexisting wells used for public supply...
Authors
Jennifer Stanton, Michael Land, Matthew Landon, David Shimabukuro, Peter McMahon, Tracy Davis, Andrew Hunt, Theron A. Sowers
Quality of groundwater used for public supply in the continental United States: A comprehensive assessment Quality of groundwater used for public supply in the continental United States: A comprehensive assessment
The presence of contaminants in a source water can constrain its suitability for drinking. The quality of groundwater used for public supply was assessed in 25 principal aquifers (PAs) that account for 84% of groundwater pumped for public supply in the U.S. (89.6 million people on a proportional basis). Each PA was sampled across its lateral extent using an equal-area grid, typically...
Authors
Kenneth Belitz, Miranda Fram, Bruce Lindsey, Paul Stackelberg, Laura Bexfield, Tyler D. Johnson, Bryant Jurgens, James Kingsbury, Peter McMahon, Neil Dubrovsky
Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination
The distribution of groundwater age is useful for evaluating the susceptibility and sustainability of groundwater resources. Here, we compute the aquifer-scale cumulative distribution function to characterize the age distribution for 21 Principal Aquifers that account for ~80% of public-supply pumping in the United States. The aquifer-scale cumulative distribution function for each...
Authors
Bryant Jurgens, Kirsten Faulkner, Peter McMahon, Andrew Hunt, Gerolamo Casile, Megan Young, Kenneth Belitz
Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA
Study region Santa Barbara County, California, USA.Study focus To analyze a wide array of newly collected chemical, isotopic, dissolved gas, and age dating tracers in conjunction with historical data from groundwater and oil wells to determine if water and/or thermogenic gas from oil-bearing formations have mixed with groundwater in the Orcutt Oil Field and surrounding area.New...
Authors
Robert Anders, Matthew Landon, Peter McMahon, Justin Kulongoski, Andrew G. Hunt, Tracy Davis
Perfluoroalkyl and polyfluoroalkyl substances in groundwater used as a source of drinking water in the eastern United States Perfluoroalkyl and polyfluoroalkyl substances in groundwater used as a source of drinking water in the eastern United States
In 2019, 254 samples were collected from five aquifer systems to evaluate per- and polyfluoroalkyl substance (PFAS) occurrence in groundwater used as a source of drinking water in the eastern United States. The samples were analyzed for 24 PFAS, major ions, nutrients, trace elements, dissolved organic carbon (DOC), volatile organic compounds (VOCs), pharmaceuticals, and tritium. Fourteen...
Authors
Peter McMahon, Andrea Tokranov, Laura Bexfield, Bruce Lindsey, Tyler D. Johnson, Melissa Lombard, Elise Watson
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 Rosecrans, Kenneth Belitz, Katherine Ransom, Peter McMahon, Paul Stackelberg