Douglas Kent
Dr. Douglas Kent is a scientist emeritus with the Earth System Processes Division of the Water Mission Area, U. S. Geological Survey.
Doug Kent received an AA from Pasadena City College, a BA in chemistry from the University of California, San Diego and a PhD from Scripps Institution of Oceanography. He has conducted hydrologic research at the USGS since 1985.
Doug Kent's research at the USGS has focused on processes influencing the mobility of constituents that can affect the availability of water for beneficial use by humans and for sustaining aquatic ecosystems.
Science and Products
Filter Total Items: 15
Simulating changes in the distribution of ammonium and ammonia versus physical and chemical conditions using PHREEQC with applications to toxicity to fish Simulating changes in the distribution of ammonium and ammonia versus physical and chemical conditions using PHREEQC with applications to toxicity to fish
Two sets of PHREEQC input and output files are provided that illustrate the distribution of aqueous ammonium and ammonia as a function of physical (temperature) and chemical (pH and solution composition) conditions. One set of simulations calculates the distribution of aqueous ammonia and aqueous ammonium over a range of temperatures and pH values in different solution compositions. The...
Water-Quality Data in and near Groundwater Flow-Through Kettle-Hole Lakes, Western Cape Cod, Massachusetts, 2003 - 2018 Water-Quality Data in and near Groundwater Flow-Through Kettle-Hole Lakes, Western Cape Cod, Massachusetts, 2003 - 2018
This U.S. Geological Survey (USGS) data release provides a comprehensive dataset of water-quality results, physical-parameter measurements, hydrologic measurements, and site information collected to study the nature and extent of water quality along groundwater flow paths adjacent to glacial-kettle lakes on Cape Cod, Massachusetts. Water-quality samples were collected in 2003, 2005, and...
Geochemistry Data for Wastewater Samples Collected at a Separator Tank and from an On-Site Storage Tank at the Marcellus Shale Energy and Environment Laboratory (MSEEL) 2015-2019, Morgantown Industrial Park (MIP), West Virginia (ver. 2.0, May 2023) Geochemistry Data for Wastewater Samples Collected at a Separator Tank and from an On-Site Storage Tank at the Marcellus Shale Energy and Environment Laboratory (MSEEL) 2015-2019, Morgantown Industrial Park (MIP), West Virginia (ver. 2.0, May 2023)
This U.S. Geological Survey (USGS) Data Release is focused on the geochemistry of wastewater (including flowback and produced water) samples, co-produced with natural gas, collected from the Marcellus Shale Energy and Environment Laboratory (MSEEL) site. MSEEL is a long-term field site and laboratory at the Northeast Natural Energy LLC (NNE) production facility, adjacent to the...
Data on the Effects of Oil and Gas Wastewater Components on Microbial Community Structure and Function Data on the Effects of Oil and Gas Wastewater Components on Microbial Community Structure and Function
Oil and gas (OG) wastewaters are commonly disposed of by underground injection and previous research showed that activities at a disposal facility in West Virginia affected stream biogeochemistry and sediment microbial communities downstream from the facility. Microorganisms can control the fate and transport of organic and inorganic components of OG wastewater highlighting the need to
Chemical Data From 40 Years of Monitoring a Treated-Wastewater Groundwater Plume in a Sand and Gravel Aquifer, Cape Cod, Massachusetts, 1978-2018 (ver. 1.1, April 2025) Chemical Data From 40 Years of Monitoring a Treated-Wastewater Groundwater Plume in a Sand and Gravel Aquifer, Cape Cod, Massachusetts, 1978-2018 (ver. 1.1, April 2025)
This U.S. Geological Survey data release provides a comprehensive dataset of water-quality data and sampling-site characteristics collected in 1978–2018 during a study of the effects of land disposal of treated wastewater on groundwater quality in an unconsolidated sand and gravel aquifer on Cape Cod, Massachusetts. Treated sewage-derived wastewater was discharged to rapid-infiltration...
Lake Ontario Water Quality and Velocity Transect Data 2015-18 Lake Ontario Water Quality and Velocity Transect Data 2015-18
From May of 2015 through September of 2018, water-quality were collected at 178 locations and velocity data were collected along 7 transects from select tributaries, embayments, and nearshore lake locations along New York's Lake Ontario waterfront in support of the Great Lakes Restoration Initiative and the Lakewide Action Management Plan. These data include: depth, velocity magnitude...
Filter Total Items: 53
Using biological responses to monitor freshwater post-spill conditions over 3 years in Blacktail Creek, North Dakota, USA Using biological responses to monitor freshwater post-spill conditions over 3 years in Blacktail Creek, North Dakota, USA
A pipeline carrying unconventional oil and gas (OG) wastewater spilled approximately 11 million liters of wastewater into Blacktail Creek, North Dakota, USA. Flow of the mix of stream water and wastewater down the channel resulted in storage of contaminants in the hyporheic zone and along the banks, providing a long-term source of wastewater constituents to the stream. A multi-level...
Authors
Aida Farag, David Harper, Isabelle M. Cozzarelli, Douglas B. Kent, Adam Mumford, Denise M. Akob, Travis W. Schaeffer, Luke R. Iwanowicz
By
Ecosystems Mission Area, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, Columbia Environmental Research Center, Earth Resources Observation and Science (EROS) Center , Eastern Ecological Science Center, Geology, Energy & Minerals Science Center, Reston Microbiology Laboratory
Integrated science for the study of perfluoroalkyl and polyfluoroalkyl substances (PFAS) in the environment—A strategic science vision for the U.S. Geological Survey Integrated science for the study of perfluoroalkyl and polyfluoroalkyl substances (PFAS) in the environment—A strategic science vision for the U.S. Geological Survey
Concerns related to perfluoroalkyl and polyfluoroalkyl substances (PFAS) in sources of drinking water and in natural and engineered environments have captured national attention over the last few decades. This report provides an overview of the science gaps that exist in the fields of study related to PFAS that are relevant to the U.S. Geological Survey mission and identifies...
Authors
Andrea K. Tokranov, Paul M. Bradley, Michael J. Focazio, Douglas B. Kent, Denis R. LeBlanc, Jeff W. McCoy, Kelly L. Smalling, Jeffery A. Steevens, Patricia L. Toccalino
Geochemical and geophysical indicators of oil and gas wastewater can trace potential exposure pathways following releases to surface waters Geochemical and geophysical indicators of oil and gas wastewater can trace potential exposure pathways following releases to surface waters
Releases of oil and gas (OG) wastewaters can have complex effects on stream-water quality and downstream organisms, due to sediment-water interactions and groundwater/surface water exchange. Previously, elevated concentrations of sodium (Na), chloride (Cl), barium (Ba), strontium (Sr), and lithium (Li), and trace hydrocarbons were determined to be key markers of OG wastewater releases...
Authors
Isabelle M. Cozzarelli, Douglas B. Kent, Martin A. Briggs, Mark A Engle, Adam Benthem, Katherine Skalak, Adam Mumford, Jeanne B. Jaeschke, Aida Farag, John W. Lane, Denise M. Akob
Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate
A previously published field-experimental investigation showed that injection of nitrate in anoxic groundwater that contained aqueous and sediment-bound Fe(II) diminished concentrations of As(V) and As(III) to below drinking-water limits. In the current study, reactive transport modeling confirmed that the observed attenuation was consistent with oxidation of Fe(II) by nitrate, leading...
Authors
Douglas B. Kent, Richard L. Smith, James Jamieson, J.K. Bohlke, Deborah A. Repert, Henning Prommer
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
Groundwater discharge delivering anthropogenic N from surrounding watersheds can impact lake nutrient budgets. However, upgradient groundwater processes and changing dynamics in N biogeochemistry at the groundwater-lake interface are complex and difficult to resolve. In this study, hydrograph variations in a groundwater flow-through lake altered discharge patterns of a wastewater-derived
Authors
Richard L. Smith, Deborah A. Repert, Deborah Stoliker, Douglas B. Kent, Bongkeun Song, Denis R. LeBlanc, Timothy D. McCobb, J.K. Bohlke, Sung Pil Hyun, Hee Sun Moon
When oil and water mix: Understanding the environmental impacts of shale development When oil and water mix: Understanding the environmental impacts of shale development
Development of shale gas and tight oil, or unconventional oil and gas (UOG), has dramatically increased domestic energy production in the U.S. UOG resources are typically developed through the use of hydraulic fracturing, which creates high-permeability flow paths into large volumes of tight rocks to provide a means for hydrocarbons to move to a wellbore. This process uses significant...
Authors
Daniel J. Soeder, Douglas B. Kent
Non-USGS Publications**
Kent, D. B., and Kastner, M., 1985, Mg2+ removal in the system Mg2+‑amorphous SiO2‑H2O by adsorption and Mg‑hydroxysilicate precipitation: Geochimica et Cosmochimica Acta, v. 49, p. 1123‑1136.
Kent, D. B., 1983, On the surface chemical properties of synthetic and biogenic amorphous silica: Ph.D. dissertation, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, California, 420 pp.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 15
Simulating changes in the distribution of ammonium and ammonia versus physical and chemical conditions using PHREEQC with applications to toxicity to fish Simulating changes in the distribution of ammonium and ammonia versus physical and chemical conditions using PHREEQC with applications to toxicity to fish
Two sets of PHREEQC input and output files are provided that illustrate the distribution of aqueous ammonium and ammonia as a function of physical (temperature) and chemical (pH and solution composition) conditions. One set of simulations calculates the distribution of aqueous ammonia and aqueous ammonium over a range of temperatures and pH values in different solution compositions. The...
Water-Quality Data in and near Groundwater Flow-Through Kettle-Hole Lakes, Western Cape Cod, Massachusetts, 2003 - 2018 Water-Quality Data in and near Groundwater Flow-Through Kettle-Hole Lakes, Western Cape Cod, Massachusetts, 2003 - 2018
This U.S. Geological Survey (USGS) data release provides a comprehensive dataset of water-quality results, physical-parameter measurements, hydrologic measurements, and site information collected to study the nature and extent of water quality along groundwater flow paths adjacent to glacial-kettle lakes on Cape Cod, Massachusetts. Water-quality samples were collected in 2003, 2005, and...
Geochemistry Data for Wastewater Samples Collected at a Separator Tank and from an On-Site Storage Tank at the Marcellus Shale Energy and Environment Laboratory (MSEEL) 2015-2019, Morgantown Industrial Park (MIP), West Virginia (ver. 2.0, May 2023) Geochemistry Data for Wastewater Samples Collected at a Separator Tank and from an On-Site Storage Tank at the Marcellus Shale Energy and Environment Laboratory (MSEEL) 2015-2019, Morgantown Industrial Park (MIP), West Virginia (ver. 2.0, May 2023)
This U.S. Geological Survey (USGS) Data Release is focused on the geochemistry of wastewater (including flowback and produced water) samples, co-produced with natural gas, collected from the Marcellus Shale Energy and Environment Laboratory (MSEEL) site. MSEEL is a long-term field site and laboratory at the Northeast Natural Energy LLC (NNE) production facility, adjacent to the...
Data on the Effects of Oil and Gas Wastewater Components on Microbial Community Structure and Function Data on the Effects of Oil and Gas Wastewater Components on Microbial Community Structure and Function
Oil and gas (OG) wastewaters are commonly disposed of by underground injection and previous research showed that activities at a disposal facility in West Virginia affected stream biogeochemistry and sediment microbial communities downstream from the facility. Microorganisms can control the fate and transport of organic and inorganic components of OG wastewater highlighting the need to
Chemical Data From 40 Years of Monitoring a Treated-Wastewater Groundwater Plume in a Sand and Gravel Aquifer, Cape Cod, Massachusetts, 1978-2018 (ver. 1.1, April 2025) Chemical Data From 40 Years of Monitoring a Treated-Wastewater Groundwater Plume in a Sand and Gravel Aquifer, Cape Cod, Massachusetts, 1978-2018 (ver. 1.1, April 2025)
This U.S. Geological Survey data release provides a comprehensive dataset of water-quality data and sampling-site characteristics collected in 1978–2018 during a study of the effects of land disposal of treated wastewater on groundwater quality in an unconsolidated sand and gravel aquifer on Cape Cod, Massachusetts. Treated sewage-derived wastewater was discharged to rapid-infiltration...
Lake Ontario Water Quality and Velocity Transect Data 2015-18 Lake Ontario Water Quality and Velocity Transect Data 2015-18
From May of 2015 through September of 2018, water-quality were collected at 178 locations and velocity data were collected along 7 transects from select tributaries, embayments, and nearshore lake locations along New York's Lake Ontario waterfront in support of the Great Lakes Restoration Initiative and the Lakewide Action Management Plan. These data include: depth, velocity magnitude...
Filter Total Items: 53
Using biological responses to monitor freshwater post-spill conditions over 3 years in Blacktail Creek, North Dakota, USA Using biological responses to monitor freshwater post-spill conditions over 3 years in Blacktail Creek, North Dakota, USA
A pipeline carrying unconventional oil and gas (OG) wastewater spilled approximately 11 million liters of wastewater into Blacktail Creek, North Dakota, USA. Flow of the mix of stream water and wastewater down the channel resulted in storage of contaminants in the hyporheic zone and along the banks, providing a long-term source of wastewater constituents to the stream. A multi-level...
Authors
Aida Farag, David Harper, Isabelle M. Cozzarelli, Douglas B. Kent, Adam Mumford, Denise M. Akob, Travis W. Schaeffer, Luke R. Iwanowicz
By
Ecosystems Mission Area, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, Columbia Environmental Research Center, Earth Resources Observation and Science (EROS) Center , Eastern Ecological Science Center, Geology, Energy & Minerals Science Center, Reston Microbiology Laboratory
Integrated science for the study of perfluoroalkyl and polyfluoroalkyl substances (PFAS) in the environment—A strategic science vision for the U.S. Geological Survey Integrated science for the study of perfluoroalkyl and polyfluoroalkyl substances (PFAS) in the environment—A strategic science vision for the U.S. Geological Survey
Concerns related to perfluoroalkyl and polyfluoroalkyl substances (PFAS) in sources of drinking water and in natural and engineered environments have captured national attention over the last few decades. This report provides an overview of the science gaps that exist in the fields of study related to PFAS that are relevant to the U.S. Geological Survey mission and identifies...
Authors
Andrea K. Tokranov, Paul M. Bradley, Michael J. Focazio, Douglas B. Kent, Denis R. LeBlanc, Jeff W. McCoy, Kelly L. Smalling, Jeffery A. Steevens, Patricia L. Toccalino
Geochemical and geophysical indicators of oil and gas wastewater can trace potential exposure pathways following releases to surface waters Geochemical and geophysical indicators of oil and gas wastewater can trace potential exposure pathways following releases to surface waters
Releases of oil and gas (OG) wastewaters can have complex effects on stream-water quality and downstream organisms, due to sediment-water interactions and groundwater/surface water exchange. Previously, elevated concentrations of sodium (Na), chloride (Cl), barium (Ba), strontium (Sr), and lithium (Li), and trace hydrocarbons were determined to be key markers of OG wastewater releases...
Authors
Isabelle M. Cozzarelli, Douglas B. Kent, Martin A. Briggs, Mark A Engle, Adam Benthem, Katherine Skalak, Adam Mumford, Jeanne B. Jaeschke, Aida Farag, John W. Lane, Denise M. Akob
Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate Reactive transport modeling to understand attenuation of arsenic concentrations in anoxic groundwater during Fe(II) oxidation by nitrate
A previously published field-experimental investigation showed that injection of nitrate in anoxic groundwater that contained aqueous and sediment-bound Fe(II) diminished concentrations of As(V) and As(III) to below drinking-water limits. In the current study, reactive transport modeling confirmed that the observed attenuation was consistent with oxidation of Fe(II) by nitrate, leading...
Authors
Douglas B. Kent, Richard L. Smith, James Jamieson, J.K. Bohlke, Deborah A. Repert, Henning Prommer
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
Groundwater discharge delivering anthropogenic N from surrounding watersheds can impact lake nutrient budgets. However, upgradient groundwater processes and changing dynamics in N biogeochemistry at the groundwater-lake interface are complex and difficult to resolve. In this study, hydrograph variations in a groundwater flow-through lake altered discharge patterns of a wastewater-derived
Authors
Richard L. Smith, Deborah A. Repert, Deborah Stoliker, Douglas B. Kent, Bongkeun Song, Denis R. LeBlanc, Timothy D. McCobb, J.K. Bohlke, Sung Pil Hyun, Hee Sun Moon
When oil and water mix: Understanding the environmental impacts of shale development When oil and water mix: Understanding the environmental impacts of shale development
Development of shale gas and tight oil, or unconventional oil and gas (UOG), has dramatically increased domestic energy production in the U.S. UOG resources are typically developed through the use of hydraulic fracturing, which creates high-permeability flow paths into large volumes of tight rocks to provide a means for hydrocarbons to move to a wellbore. This process uses significant...
Authors
Daniel J. Soeder, Douglas B. Kent
Non-USGS Publications**
Kent, D. B., and Kastner, M., 1985, Mg2+ removal in the system Mg2+‑amorphous SiO2‑H2O by adsorption and Mg‑hydroxysilicate precipitation: Geochimica et Cosmochimica Acta, v. 49, p. 1123‑1136.
Kent, D. B., 1983, On the surface chemical properties of synthetic and biogenic amorphous silica: Ph.D. dissertation, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, California, 420 pp.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.