Thomas Chapin
Thomas Chapin is a Research Chemist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Assessing the impacts of mining on the Transboundary Koocanusa Reservoir
Lead Researcher: Travis Schmidt Project Manager: Melissa Schaar Water-Quality Field Lead: Chad Reese
Laboratory-based optical measurements for surface water samples collected within the Fraser River in the Upper Colorado River Basin from September 2021 through September 2023
Optical spectra reported here are collected from 17 surface water sampling sites within the Fraser River, a headwaters drainage of the Upper Colorado River Basin in the central western United States. The sample collection was conducted as part of the partnership between the United States Geological Survey’s (USGS) Next Generation Water Observation System (NGWOS) and Proxies Project, in coordinatio
Water Quality Data from Select Spring and Stream Sites and Water and Sediment Quality Data from the Colorado River and Major Tributaries in Grand Canyon, Northern Arizona (ver. 2.0, April 2024)
This USGS Data Release represents water and sediment quality data collected in the Grand Canyon region of northern Arizona.
There are 4 separate datasets associated with this Data Release:
Water quality data from major Colorado River tributary monitoring sites in and near Grand Canyon from 2015 through 2022.
Sediment quality data from the Colorado River and major tributary monitoring sites in an
Sampling and analysis plan for the Koocanusa Reservoir and upper Kootenai River, Montana, water-quality monitoring program, 2021
In 2021, the U.S. Geological Survey will collect water-quality samples and environmental data from 3 sites in Koocanusa Reservoir and from 1 site in the Kootenai River. The transboundary Koocanusa Reservoir is in southeastern British Columbia, Canada, and northwestern Montana, United States, and was formed with the construction of Libby Dam on the Kootenai River 26 kilometers upstream from Libby,
Authors
Sara L. Caldwell Eldridge, Melissa A. Schaar, Chad B. Reese, Ashley M. Bussell, Thomas Chapin
Assessing uranium and select trace elements associated with breccia pipe uranium deposits in the Colorado River and main tributaries in Grand Canyon, USA
Assessing chemical loading from streams in remote, difficult-to-access watersheds is challenging. The Grand Canyon area in northern Arizona, an international tourist destination and sacred place for many Native Americans, is characterized by broad plateaus divided by canyons as much as two-thousand meters deep and hosts some of the highest-grade uranium deposits in the U.S. From 2015–2018 major su
Authors
Fred D. Tillman, Jessica R. Anderson, Joel A. Unema, Thomas Chapin
New perspectives on a 140-year legacy of mining and abandoned mine cleanup in the San Juan Mountains, Colorado
The Gold King mine water release that occurred on 5 August 2015 near the historical mining community of Silverton, Colorado, highlights the environmental legacy that abandoned mines have on the environment. During reclamation efforts, a breach of collapsed workings at the Gold King mine sent 3 million gallons of acidic and metal-rich mine water into the upper Animas River, a tributary to the Color
Authors
Douglas B. Yager, David L. Fey, Thomas Chapin, Raymond H. Johnson
High-frequency, long-duration water sampling in acid mine drainage studies: a short review of current methods and recent advances in automated water samplers
Hand-collected grab samples are the most common water sampling method but using grab sampling to monitor temporally variable aquatic processes such as diel metal cycling or episodic events is rarely feasible or cost-effective. Currently available automated samplers are a proven, widely used technology and typically collect up to 24 samples during a deployment. However, these automated samplers are
Authors
Thomas Chapin
Robust, low-cost data loggers for stream temperature, flow intermittency, and relative conductivity monitoring
Water temperature and streamflow intermittency are critical parameters influencing aquatic ecosystem health. Low-cost temperature loggers have made continuous water temperature monitoring relatively simple but determining streamflow timing and intermittency using temperature data alone requires significant and subjective data interpretation. Electrical resistance (ER) sensors have recently been de
Authors
Thomas Chapin, Andrew S. Todd, Matthew P. Zeigler
High nutrient pulses, tidal mixing and biological response in a small California estuary: Variability in nutrient concentrations from decadal to hourly time scales
Elkhorn Slough is a small estuary in Central California, where nutrient inputs are dominated by runoff from agricultural row crops, a golf course, and residential development. We examined the variability in nutrient concentrations from decadal to hourly time scales in Elkhorn Slough to compare forcing by physical and biological factors. Hourly data were collected using in situ nitrate analyzers an
Authors
J.M. Caffrey, T.P. Chapin, H.W. Jannasch, J.C. Haskins
Development of a solenoid pumped in situ zinc analyzer for environmental monitoring
A battery powered submersible chemical analyzer, the Zn-DigiScan (Zn Digital Submersible Chemical Analyzer), has been developed for near real-time, in situ monitoring of zinc in aquatic systems. Microprocessor controlled solenoid pumps propel sample and carrier through an anion exchange column to separate zinc from interferences, add colorimetric reagents, and propel the reaction complex through a
Authors
T.P. Chapin, R. B. Wanty
Nitrate sources and sinks in Elkhorn Slough, California: Results from long-term continuous in situ nitrate analyzers
Nitrate and water quality parameters (temperature, salinity, dissolved oxygen, turbidity, and depth) were measured continuously with in situ NO3 analyzers and water quality sondes at two sites in Elkhorn Slough in Central California. The Main Channel site near the mouth of Elkhorn Slough was sampled from February to September 2001. Azevedo Pond, a shallow tidal pond bordering agricultural fields f
Authors
T.P. Chapin, J.M. Caffrey, H.W. Jannasch, L.J. Coletti, J.C. Haskins, K.S. Johnson
In situ osmotic analyzer for the year-long continuous determination of Fe in hydrothermal systems
A submersible osmotically pumped analyzer (Fe-OsmoAnalyzer) has been adapted for the long-term continuous high resolution monitoring of iron(II) and (III) in deep-sea hydrothermal vents. Ferrozine is used as the colorimetric reagent. The detection limit for our analyzer is 0.1??M for a 0.7cm pathlength with a linear response up to 50??M. The Fe-OsmoAnalyzer uses periodic injections of standards an
Authors
T.P. Chapin, H.W. Jannasch, K.S. Johnson
Science and Products
Assessing the impacts of mining on the Transboundary Koocanusa Reservoir
Lead Researcher: Travis Schmidt Project Manager: Melissa Schaar Water-Quality Field Lead: Chad Reese
Laboratory-based optical measurements for surface water samples collected within the Fraser River in the Upper Colorado River Basin from September 2021 through September 2023
Optical spectra reported here are collected from 17 surface water sampling sites within the Fraser River, a headwaters drainage of the Upper Colorado River Basin in the central western United States. The sample collection was conducted as part of the partnership between the United States Geological Survey’s (USGS) Next Generation Water Observation System (NGWOS) and Proxies Project, in coordinatio
Water Quality Data from Select Spring and Stream Sites and Water and Sediment Quality Data from the Colorado River and Major Tributaries in Grand Canyon, Northern Arizona (ver. 2.0, April 2024)
This USGS Data Release represents water and sediment quality data collected in the Grand Canyon region of northern Arizona.
There are 4 separate datasets associated with this Data Release:
Water quality data from major Colorado River tributary monitoring sites in and near Grand Canyon from 2015 through 2022.
Sediment quality data from the Colorado River and major tributary monitoring sites in an
Sampling and analysis plan for the Koocanusa Reservoir and upper Kootenai River, Montana, water-quality monitoring program, 2021
In 2021, the U.S. Geological Survey will collect water-quality samples and environmental data from 3 sites in Koocanusa Reservoir and from 1 site in the Kootenai River. The transboundary Koocanusa Reservoir is in southeastern British Columbia, Canada, and northwestern Montana, United States, and was formed with the construction of Libby Dam on the Kootenai River 26 kilometers upstream from Libby,
Authors
Sara L. Caldwell Eldridge, Melissa A. Schaar, Chad B. Reese, Ashley M. Bussell, Thomas Chapin
Assessing uranium and select trace elements associated with breccia pipe uranium deposits in the Colorado River and main tributaries in Grand Canyon, USA
Assessing chemical loading from streams in remote, difficult-to-access watersheds is challenging. The Grand Canyon area in northern Arizona, an international tourist destination and sacred place for many Native Americans, is characterized by broad plateaus divided by canyons as much as two-thousand meters deep and hosts some of the highest-grade uranium deposits in the U.S. From 2015–2018 major su
Authors
Fred D. Tillman, Jessica R. Anderson, Joel A. Unema, Thomas Chapin
New perspectives on a 140-year legacy of mining and abandoned mine cleanup in the San Juan Mountains, Colorado
The Gold King mine water release that occurred on 5 August 2015 near the historical mining community of Silverton, Colorado, highlights the environmental legacy that abandoned mines have on the environment. During reclamation efforts, a breach of collapsed workings at the Gold King mine sent 3 million gallons of acidic and metal-rich mine water into the upper Animas River, a tributary to the Color
Authors
Douglas B. Yager, David L. Fey, Thomas Chapin, Raymond H. Johnson
High-frequency, long-duration water sampling in acid mine drainage studies: a short review of current methods and recent advances in automated water samplers
Hand-collected grab samples are the most common water sampling method but using grab sampling to monitor temporally variable aquatic processes such as diel metal cycling or episodic events is rarely feasible or cost-effective. Currently available automated samplers are a proven, widely used technology and typically collect up to 24 samples during a deployment. However, these automated samplers are
Authors
Thomas Chapin
Robust, low-cost data loggers for stream temperature, flow intermittency, and relative conductivity monitoring
Water temperature and streamflow intermittency are critical parameters influencing aquatic ecosystem health. Low-cost temperature loggers have made continuous water temperature monitoring relatively simple but determining streamflow timing and intermittency using temperature data alone requires significant and subjective data interpretation. Electrical resistance (ER) sensors have recently been de
Authors
Thomas Chapin, Andrew S. Todd, Matthew P. Zeigler
High nutrient pulses, tidal mixing and biological response in a small California estuary: Variability in nutrient concentrations from decadal to hourly time scales
Elkhorn Slough is a small estuary in Central California, where nutrient inputs are dominated by runoff from agricultural row crops, a golf course, and residential development. We examined the variability in nutrient concentrations from decadal to hourly time scales in Elkhorn Slough to compare forcing by physical and biological factors. Hourly data were collected using in situ nitrate analyzers an
Authors
J.M. Caffrey, T.P. Chapin, H.W. Jannasch, J.C. Haskins
Development of a solenoid pumped in situ zinc analyzer for environmental monitoring
A battery powered submersible chemical analyzer, the Zn-DigiScan (Zn Digital Submersible Chemical Analyzer), has been developed for near real-time, in situ monitoring of zinc in aquatic systems. Microprocessor controlled solenoid pumps propel sample and carrier through an anion exchange column to separate zinc from interferences, add colorimetric reagents, and propel the reaction complex through a
Authors
T.P. Chapin, R. B. Wanty
Nitrate sources and sinks in Elkhorn Slough, California: Results from long-term continuous in situ nitrate analyzers
Nitrate and water quality parameters (temperature, salinity, dissolved oxygen, turbidity, and depth) were measured continuously with in situ NO3 analyzers and water quality sondes at two sites in Elkhorn Slough in Central California. The Main Channel site near the mouth of Elkhorn Slough was sampled from February to September 2001. Azevedo Pond, a shallow tidal pond bordering agricultural fields f
Authors
T.P. Chapin, J.M. Caffrey, H.W. Jannasch, L.J. Coletti, J.C. Haskins, K.S. Johnson
In situ osmotic analyzer for the year-long continuous determination of Fe in hydrothermal systems
A submersible osmotically pumped analyzer (Fe-OsmoAnalyzer) has been adapted for the long-term continuous high resolution monitoring of iron(II) and (III) in deep-sea hydrothermal vents. Ferrozine is used as the colorimetric reagent. The detection limit for our analyzer is 0.1??M for a 0.7cm pathlength with a linear response up to 50??M. The Fe-OsmoAnalyzer uses periodic injections of standards an
Authors
T.P. Chapin, H.W. Jannasch, K.S. Johnson