Robert Kent (Former Employee)
Science and Products
Data for Per- and Polyfluoroalkyl Substances (PFAS) in groundwater samples collected by the California Groundwater Ambient Monitoring and Assessment Priority Basin Project, 2019-2023
The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) analyzed for per-and polyfluoroalkyl substances (PFAS) in groundwater samples collected from domestic and public drinking water supply wells in California. GAMA-PBP is a cooperative program between the U.S. Geological Survey and the California State Water Resources Control Board.
This data relea
Data sets for: Sampling for Per- and Polyfluoroalkyl Substances (PFAS) by the Groundwater Ambient Monitoring and Assessment Priority Basin Project (GAMA-PBP)
The U.S. Geological Survey Groundwater Ambient Monitoring and Assessment-Priority Basin Project (USGS GAMA-PBP) collected samples to be analyzed for per-and polyfluoroalkyl substances (PFAS) from domestic and public supply wells from May 2019 to September 2020. The datasets presented here include identification of the 28 PFAS constituents monitored by the project, Identification and brief characte
Data sets for: Variations on a method for evaluating decadal-scale changes in the groundwater quality of two GAMA coastal study units 2004-2014, California GAMA Priority Basin Project
The U.S. Geological Survey collected samples from 50 public supply wells during two distinct sampling episodes (2004-2005 and 2014) on the North-Central California coast. During each sampling episode, the samples were analyzed for 160 water-quality constituents, including water-quality indicators, nutrients, major and minor ions, trace elements, volatile organic compounds, and pesticide compounds.
Filter Total Items: 14
Sampling for Per- and Polyfluoroalkyl Substances (PFAS) by the Groundwater Ambient Monitoring and Assessment Priority Basin Project
Per- and polyfluoroalkyl substances (PFAS) are a family of human-made chemicals that can persist in the environment. In 2019, the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment Priority Basin Project (GAMA-PBP) added PFAS to the projects’ on-going assessments of the quality of groundwater used for drinking-water supplies. This fact sheet describes th
Authors
Robert H. Kent
Variations on a method for evaluating decadal-scale changes in the groundwater quality of two GAMA coastal study units 2004–14, California GAMA Priority Basin Project
Decadal changes in groundwater quality in two study units on the north-central California coast were evaluated by the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. Groundwater samples collected from wells during 2004–05 were compared on a pair-wise basis to samples collected from the same wells during 2014. The data set consisted of paired-sample
Authors
Robert H. Kent
Triennial changes in groundwater quality in aquifers used for public supply in California: Utility as indicators of temporal trends
From 2004 to 2011, the U.S. Geological Survey collected samples from 1686 wells across the State of California as part of the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment (GAMA) Priority Basin Project (PBP). From 2007 to 2013, 224 of these wells were resampled to assess temporal trends in water quality. The samples were analyzed for 216 water-quali
Authors
Robert H. Kent, Matthew K. Landon
Groundwater quality data in 15 GAMA study units: results from the 2006–10 Initial sampling and the 2009–13 resampling of wells, California GAMA Priority Basin Project
The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). From May 2004 to March 2012, the GAMA-PBP collected samples from more than 2,300 we
Authors
Robert Kent
Groundwater-quality data in seven GAMA study units: results from initial sampling, 2004-2005, and resampling, 2007-2008, of wells: California GAMA Program Priority Basin Project
The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The GAMA-PBP began sampling, primarily public supply wells in May 2004. By the end
Authors
Robert H. Kent, Kenneth Belitz, Miranda S. Fram
Trends in concentrations of nitrate and total dissolved solids in public supply wells of the Bunker Hill, Lytle, Rialto, and Colton groundwater subbasins, San Bernardino County, California: Influence of legacy land use
Concentrations and temporal changes in concentrations of nitrate and total dissolved solids (TDS) in groundwater of the Bunker Hill, Lytle, Rialto, and Colton groundwater subbasins of the Upper Santa Ana Valley Groundwater Basin were evaluated to identify trends and factors that may be affecting trends. One hundred, thirty-one public-supply wells were selected for analysis based on the availabilit
Authors
Robert Kent, Matthew K. Landon
Groundwater quality in the Upper Santa Ana Watershed study unit, California
Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The Upper Sant
Authors
Robert Kent, Kenneth Belitz
Status of groundwater quality in the Upper Santa Ana Watershed, November 2006--March 2007--California GAMA Priority Basin Project
Groundwater quality in the approximately 1,000-square-mile (2,590-square-kilometer) Upper Santa Ana Watershed (USAW) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in southern California in Riverside and San Bernardino Counties. The GAMA Priority Basin Project is being conducted by the
Authors
Robert Kent, Kenneth Belitz
Trends in nutrient concentrations, loads, and yields in streams in the Sacramento, San Joaquin, and Santa Ana Basins, California, 1975-2004
A comprehensive database was assembled for the Sacramento, San Joaquin, and Santa Ana Basins in California on nutrient concentrations, flows, and point and nonpoint sources of nutrients for 1975-2004. Most of the data on nutrient concentrations (nitrate, ammonia, total nitrogen, orthophosphate, and total phosphorus) were from the U.S. Geological Survey's National Water Information System database
Authors
Charles R. Kratzer, Robert Kent, Dina K. Seleh, Donna L. Knifong, Peter D. Dileanis, James L. Orlando
Ground-Water Quality Data in the Upper Santa Ana Watershed Study Unit, November 2006-March 2007: Results from the California GAMA Program
Ground-water quality in the approximately 1,000-square-mile Upper Santa Ana Watershed study unit (USAW) was investigated from November 2006 through March 2007 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by
Authors
Robert Kent, Kenneth Belitz
Occurrence and distribution of pesticide compounds in surface water of the Santa Ana basin, California, 1998-2001
A study of the occurrence and distribution of pesticide compounds in surface water of the highly urbanized Santa Ana Basin, California, was done as part of the U.S. Geological Survey's National Water-Quality Assessment Program (NAWQA). One-hundred and forty-eight samples were collected from 23 sites, and analyzed for pesticide compounds during the study period from November 1998 to September 2001
Authors
Robert Kent, Kenneth Belitz, Andrea J. Altmann, Michael T. Wright, Gregory O. Mendez
Algal productivity and nitrate assimilation in an effluent dominated concrete lined stream
This study examined algal productivity and nitrate assimilation in a 2.85 km reach of Cucamonga Creek, California, a concrete lined channel receiving treated municipal wastewater. Stream nitrate concentrations observed at two stations indicated nearly continuous loss throughout the diel study. Nitrate loss in the reach was approximately 11 mg/L/d or 1.0 g/m2/d as N, most of which occurred during d
Authors
Robert Kent, Kenneth Belitz, Carmen A. Burton
Science and Products
Data for Per- and Polyfluoroalkyl Substances (PFAS) in groundwater samples collected by the California Groundwater Ambient Monitoring and Assessment Priority Basin Project, 2019-2023
The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) analyzed for per-and polyfluoroalkyl substances (PFAS) in groundwater samples collected from domestic and public drinking water supply wells in California. GAMA-PBP is a cooperative program between the U.S. Geological Survey and the California State Water Resources Control Board.
This data relea
Data sets for: Sampling for Per- and Polyfluoroalkyl Substances (PFAS) by the Groundwater Ambient Monitoring and Assessment Priority Basin Project (GAMA-PBP)
The U.S. Geological Survey Groundwater Ambient Monitoring and Assessment-Priority Basin Project (USGS GAMA-PBP) collected samples to be analyzed for per-and polyfluoroalkyl substances (PFAS) from domestic and public supply wells from May 2019 to September 2020. The datasets presented here include identification of the 28 PFAS constituents monitored by the project, Identification and brief characte
Data sets for: Variations on a method for evaluating decadal-scale changes in the groundwater quality of two GAMA coastal study units 2004-2014, California GAMA Priority Basin Project
The U.S. Geological Survey collected samples from 50 public supply wells during two distinct sampling episodes (2004-2005 and 2014) on the North-Central California coast. During each sampling episode, the samples were analyzed for 160 water-quality constituents, including water-quality indicators, nutrients, major and minor ions, trace elements, volatile organic compounds, and pesticide compounds.
Filter Total Items: 14
Sampling for Per- and Polyfluoroalkyl Substances (PFAS) by the Groundwater Ambient Monitoring and Assessment Priority Basin Project
Per- and polyfluoroalkyl substances (PFAS) are a family of human-made chemicals that can persist in the environment. In 2019, the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment Priority Basin Project (GAMA-PBP) added PFAS to the projects’ on-going assessments of the quality of groundwater used for drinking-water supplies. This fact sheet describes th
Authors
Robert H. Kent
Variations on a method for evaluating decadal-scale changes in the groundwater quality of two GAMA coastal study units 2004–14, California GAMA Priority Basin Project
Decadal changes in groundwater quality in two study units on the north-central California coast were evaluated by the Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. Groundwater samples collected from wells during 2004–05 were compared on a pair-wise basis to samples collected from the same wells during 2014. The data set consisted of paired-sample
Authors
Robert H. Kent
Triennial changes in groundwater quality in aquifers used for public supply in California: Utility as indicators of temporal trends
From 2004 to 2011, the U.S. Geological Survey collected samples from 1686 wells across the State of California as part of the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment (GAMA) Priority Basin Project (PBP). From 2007 to 2013, 224 of these wells were resampled to assess temporal trends in water quality. The samples were analyzed for 216 water-quali
Authors
Robert H. Kent, Matthew K. Landon
Groundwater quality data in 15 GAMA study units: results from the 2006–10 Initial sampling and the 2009–13 resampling of wells, California GAMA Priority Basin Project
The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). From May 2004 to March 2012, the GAMA-PBP collected samples from more than 2,300 we
Authors
Robert Kent
Groundwater-quality data in seven GAMA study units: results from initial sampling, 2004-2005, and resampling, 2007-2008, of wells: California GAMA Program Priority Basin Project
The Priority Basin Project (PBP) of the Groundwater Ambient Monitoring and Assessment (GAMA) Program was developed in response to the Groundwater Quality Monitoring Act of 2001 and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The GAMA-PBP began sampling, primarily public supply wells in May 2004. By the end
Authors
Robert H. Kent, Kenneth Belitz, Miranda S. Fram
Trends in concentrations of nitrate and total dissolved solids in public supply wells of the Bunker Hill, Lytle, Rialto, and Colton groundwater subbasins, San Bernardino County, California: Influence of legacy land use
Concentrations and temporal changes in concentrations of nitrate and total dissolved solids (TDS) in groundwater of the Bunker Hill, Lytle, Rialto, and Colton groundwater subbasins of the Upper Santa Ana Valley Groundwater Basin were evaluated to identify trends and factors that may be affecting trends. One hundred, thirty-one public-supply wells were selected for analysis based on the availabilit
Authors
Robert Kent, Matthew K. Landon
Groundwater quality in the Upper Santa Ana Watershed study unit, California
Groundwater provides more than 40 percent of California's drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project of the GAMA Program provides a comprehensive assessment of the State's groundwater quality and increases public access to groundwater-quality information. The Upper Sant
Authors
Robert Kent, Kenneth Belitz
Status of groundwater quality in the Upper Santa Ana Watershed, November 2006--March 2007--California GAMA Priority Basin Project
Groundwater quality in the approximately 1,000-square-mile (2,590-square-kilometer) Upper Santa Ana Watershed (USAW) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in southern California in Riverside and San Bernardino Counties. The GAMA Priority Basin Project is being conducted by the
Authors
Robert Kent, Kenneth Belitz
Trends in nutrient concentrations, loads, and yields in streams in the Sacramento, San Joaquin, and Santa Ana Basins, California, 1975-2004
A comprehensive database was assembled for the Sacramento, San Joaquin, and Santa Ana Basins in California on nutrient concentrations, flows, and point and nonpoint sources of nutrients for 1975-2004. Most of the data on nutrient concentrations (nitrate, ammonia, total nitrogen, orthophosphate, and total phosphorus) were from the U.S. Geological Survey's National Water Information System database
Authors
Charles R. Kratzer, Robert Kent, Dina K. Seleh, Donna L. Knifong, Peter D. Dileanis, James L. Orlando
Ground-Water Quality Data in the Upper Santa Ana Watershed Study Unit, November 2006-March 2007: Results from the California GAMA Program
Ground-water quality in the approximately 1,000-square-mile Upper Santa Ana Watershed study unit (USAW) was investigated from November 2006 through March 2007 as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by
Authors
Robert Kent, Kenneth Belitz
Occurrence and distribution of pesticide compounds in surface water of the Santa Ana basin, California, 1998-2001
A study of the occurrence and distribution of pesticide compounds in surface water of the highly urbanized Santa Ana Basin, California, was done as part of the U.S. Geological Survey's National Water-Quality Assessment Program (NAWQA). One-hundred and forty-eight samples were collected from 23 sites, and analyzed for pesticide compounds during the study period from November 1998 to September 2001
Authors
Robert Kent, Kenneth Belitz, Andrea J. Altmann, Michael T. Wright, Gregory O. Mendez
Algal productivity and nitrate assimilation in an effluent dominated concrete lined stream
This study examined algal productivity and nitrate assimilation in a 2.85 km reach of Cucamonga Creek, California, a concrete lined channel receiving treated municipal wastewater. Stream nitrate concentrations observed at two stations indicated nearly continuous loss throughout the diel study. Nitrate loss in the reach was approximately 11 mg/L/d or 1.0 g/m2/d as N, most of which occurred during d
Authors
Robert Kent, Kenneth Belitz, Carmen A. Burton