Carl is a Research Soil Scientist with the U.S. Geological Survey in the Colorado Water Science Center.
My research examines the geochemical interactions between water, rock, and soil in both natural and human-managed systems. I specialize in using isotopes and geochemical tracers to answer questions of both basic and applied research. Areas of focus in my recent work include:
- Salinity in surface waters and soils of the semiarid western U.S.
- Water quality in relation to uranium mining
- Improving the 100-year-old methodology for quantifying soil geochemical development
- Applying stable isotopes of water to understanding water availability in the Headwaters of the Colorado and Gunnison River Basin as part of the USGS Next Generation Water Observing System (NGWOS)
Science and Products
Technique Used to Distinguish Natural Background from Human-Caused Enrichment of Trace Elements in Soils
Human activities can enrich toxic trace elements like uranium and arsenic in the environment, but these elements also are from natural sources and occur at background levels. Scientists utilized a technique that identifies the background and the elemental fingerprint of human-caused enrichment and tested the new technique on data collected near uranium mines in Arizona.
Soil Disturbance Can Increase Stream Salinity in Semiarid Watersheds
Soil disturbance from construction of roads, pipelines, and well pads on naturally salt-rich soils was determined to be a potential factor resulting in increased salinity in a southern Wyoming stream. Construction can expose salt-rich soils in the subsurface to increased contact with rain and snow, thus mobilizing salts through runoff or water percolating into soils.
Geochemical data from batch experiments to test mobility of trace elements downgradient from breccia-pipe uranium deposits
This data release includes solid and aqueous chemical data related to a set of sequential laboratory batch experiments conducted to test and simulate the mobility of trace elements as natural waters contact ore from breccia pipe uranium (BPU) deposits located in northern Arizona. The experiments made use of aquifer-related, sedimentary rocks collected specifically for this study and archival ore m
GIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements
In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.). Acquiring information on possible domestic sources of these critical minerals is the basis of the USGS Earth Mappi
Surface Materials Data from Breccia-Pipe Uranium Mine and Reference Sites, Arizona, USA
This data release includes elemental analysis of soil samples collected at breccia-pipe uranium mines, at one undeveloped breccia-pipe uranium deposit, and at a reference site in northern Arizona. Samples were collected near the Arizona 1, Canyon, Kanab North, and Pinenut uranium mines, over the EZ2 breccia-pipe uranium deposit, and at the Little Robinson Tank reference site. Samples were collect
Laboratory data from testing parameters of EPA Method 3060A on Soils Contaminated with Chromium Ore Processing Residue 2013-2016
It has been shown that EPA Method 3060A does not adequately extract Cr(VI) from solids containing chromium ore processing residue (COPR). We systematically tested modifications to prescribed parameters of EPA 3060A towards improving extraction efficiency of Cr(VI) from NIST SRM 2701, a standard COPR-contaminated soil from New Jersey (NJ). The alkaline extraction fluid leached Al, Si, and B from th
Filter Total Items: 21
Examination of dissolved uranium concentrations in regional shallow groundwater relative to Operable Unit 8 of the Denver Radium Superfund Site
A radium industry existed between about 1914 and 1920 in Denver, Colorado, with operations located along the South Platte River. Sites associated with that industry were contaminated with radium and uranium processing residues and were incorporated into clean-up efforts as Operating Units (OUs) of the Denver Radium Superfund Site. Concentrations of uranium exceeding the U.S. Environmental Protecti
Authors
Carleton R. Bern
Characterization of and temporal changes in groundwater quality of the Upper Black Squirrel Creek Basin, El Paso County, Colorado, 2018–20
In 2018–20, the U.S. Geological Survey, in cooperation with Upper Black Squirrel Creek Ground Water Management District, sampled 48 wells for Phase III of a multiphase plan investigating groundwater quality in the alluvial aquifer of the Upper Black Squirrel Creek Basin (UBSB), El Paso County, Colorado. Results for samples collected from October to December each year were used to assess spatial an
Authors
Zachary D. Kisfalusi, Nancy J. Bauch, Carleton R. Bern
Laboratory simulation of groundwater along uranium-mining-affected flow paths near the Grand Canyon, Arizona, USA
Mining of volumetrically small, but relatively enriched (average 0.6% U3O8) breccia pipe uranium (BPU) deposits near the Grand Canyon, Arizona, USA has the potential to affect groundwater and springs in the area. Such deposits also contain base metal sulfides that can oxidize to generate acid mine drainage and release trace metals. In this study, sequential batch experiments were conducted to simu
Authors
Carleton R. Bern, Kate M. Campbell, Katherine Walton-Day, Bradley S. Van Gosen
Water–rock interaction and the concentrations of major, trace, and rare earth elements in hydrocarbon-associated produced waters of the United States
Studies of co-produced waters from hydrocarbon extraction across multiple energy-producing basins have generally focused on major ions or a few select tracers, and studies that examine trace elements and involve laboratory experiments have generally been basin specific. Here, new perspective is sought through a broad analysis of concentration data for 26 elements from three hydrocarbon well types
Authors
Carleton R. Bern, Justin E. Birdwell, Aaron M. Jubb
Nontuberculous mycobacterial disease and molybdenum in Colorado watersheds
Nontuberculous mycobacteria (NTM) are environmental bacteria that may cause chronic lung disease. Environmental factors that favor NTM growth likely increase the risk of NTM exposure within specific environments. We aimed to identify water-quality constituents (Al, As, Cd, Ca, Cu, Fe, Pb, Mg, Mn, Mo, Ni, K, Se, Na, Zn, and pH) associated with NTM disease across Colorado watersheds. We conducted a
Authors
Ettie M Lipner, Joshua French, Carleton R. Bern, Katherine Walton-Day, David Knox, Michael Strong, D. Rebecca Prevots, James L Crooks
Salt flushing, salt storage, and controls on selenium: A 31-year mass-balance analysis of an irrigated, semiarid valley
Salinity, selenium, and uranium pose water‐quality challenges for the Arkansas River in southeastern Colorado and other rivers that support irrigation in semiarid regions. This study used 31 years of continuous discharge and specific conductance (SC) monitoring data to assess interannual patterns in water quality using mass balance on a 120‐km reach of river. Discrete sampling data were used to li
Authors
Carleton R. Bern, Michael J. Holmberg, Zachary D. Kisfalusi
Effects of John Martin Reservoir on water quality and quantity: Assessment by chemical, isotopic, and mass-balance methods
Water quality and quantity can be influenced by transit through and storage in reservoirs. Assessing such effects can be challenging, however, because of mixing and residence times, and inter-annual net storage and release from both the reservoir itself and surrounding porosity. Here, different methodologies were used to assess the effect of John Martin Reservoir (JMR), located on the Arkansas Riv
Authors
Carleton R. Bern, Michael J. Holmberg, Zachary D. Kisfalusi
Comment on “Particle fluxes in groundwater change subsurface rock chemistry over geologic time”
Over the last decade, studies at the Shale Hills Critical Zone Observatory (Shale Hills) have greatly expanded knowledge of weathering in previously understudied, shale-mantled terrains, as well as Earth's Critical Zone as a whole. Among the many discoveries made was the importance of redistribution and losses of micron-sized particles during development of shale-derived soils. A geochemical finge
Authors
Carleton R. Bern, Tiffany Yesavage
Improved enrichment factor calculations through principal component analysis: Examples from soils near breccia pipe uranium mines, Arizona, USA
The enrichment factor (EF) is a widely used metric for determining how much the presence of an element in a sampling media has increased relative to average natural abundance because of human activity. Calculation of an EF requires the selection of both a background composition and a reference element, choices that can strongly influence the result of the calculation. Here, it is shown how careful
Authors
Carleton R. Bern, Katherine Walton-Day, David L. Naftz
Dual-phase mass balance modeling of small mineral particle losses from sedimentary rock-derived soils
Losses of small mineral particles can be a significant physical process that affects the elemental composition of soils derived from sedimentary rocks. Shales, in particular, contain abundant clay-sized minerals that can be mobilized by simple disaggregation, and solutional weathering is limited because the parent rock is composed primarily of recalcitrant minerals previously subjected to continen
Authors
Carleton R. Bern, Tiffany Yesavage
Colloid mobilization and seasonal variability in a semiarid headwater stream
Colloids can be important vectors for the transport of contaminants in the environment, but little is known about colloid mobilization at the watershed scale. We present colloid concentration, composition, and flux data over a large range of hydrologic conditions from a small watershed (Gordon Gulch) in the foothills of the Colorado Front Range. Colloids, consisting predominantly of Si, Fe, and Al
Authors
Taylor J. Mills, Suzanne P. Ancerson, Carleton R. Bern, Arnulfo Aguirre, Louis A. Derry
Iron isotope systematics of shale-derived soils as potentially influenced by small mineral particle loss
Loss of small mineral particles from soil has been suggested as a process that can produce net isotopic fractionation in the remaining soil. We extracted water dispersible colloids (WDCs) from bulk soil collected at the Susquehanna/Shale Hills Critical Zone Observatory (SSHO) and measured their Fe isotopic composition for comparison to published data from the site. The goal was to explain soil δ56
Authors
Carleton R. Bern, Tiffany Yesavage, Michael Pribil
Science and Products
- Science
Technique Used to Distinguish Natural Background from Human-Caused Enrichment of Trace Elements in Soils
Human activities can enrich toxic trace elements like uranium and arsenic in the environment, but these elements also are from natural sources and occur at background levels. Scientists utilized a technique that identifies the background and the elemental fingerprint of human-caused enrichment and tested the new technique on data collected near uranium mines in Arizona.Soil Disturbance Can Increase Stream Salinity in Semiarid Watersheds
Soil disturbance from construction of roads, pipelines, and well pads on naturally salt-rich soils was determined to be a potential factor resulting in increased salinity in a southern Wyoming stream. Construction can expose salt-rich soils in the subsurface to increased contact with rain and snow, thus mobilizing salts through runoff or water percolating into soils. - Data
Geochemical data from batch experiments to test mobility of trace elements downgradient from breccia-pipe uranium deposits
This data release includes solid and aqueous chemical data related to a set of sequential laboratory batch experiments conducted to test and simulate the mobility of trace elements as natural waters contact ore from breccia pipe uranium (BPU) deposits located in northern Arizona. The experiments made use of aquifer-related, sedimentary rocks collected specifically for this study and archival ore mGIS and Data Tables for Focus Areas for Potential Domestic Nonfuel Sources of Rare Earth Elements
In response to Executive Order 13817 of December 20, 2017, the U.S. Geological Survey (USGS) coordinated with the Bureau of Land Management (BLM) to identify 35 nonfuel minerals or mineral materials considered critical to the economic and national security of the United States (U.S.). Acquiring information on possible domestic sources of these critical minerals is the basis of the USGS Earth MappiSurface Materials Data from Breccia-Pipe Uranium Mine and Reference Sites, Arizona, USA
This data release includes elemental analysis of soil samples collected at breccia-pipe uranium mines, at one undeveloped breccia-pipe uranium deposit, and at a reference site in northern Arizona. Samples were collected near the Arizona 1, Canyon, Kanab North, and Pinenut uranium mines, over the EZ2 breccia-pipe uranium deposit, and at the Little Robinson Tank reference site. Samples were collectLaboratory data from testing parameters of EPA Method 3060A on Soils Contaminated with Chromium Ore Processing Residue 2013-2016
It has been shown that EPA Method 3060A does not adequately extract Cr(VI) from solids containing chromium ore processing residue (COPR). We systematically tested modifications to prescribed parameters of EPA 3060A towards improving extraction efficiency of Cr(VI) from NIST SRM 2701, a standard COPR-contaminated soil from New Jersey (NJ). The alkaline extraction fluid leached Al, Si, and B from th - Publications
Filter Total Items: 21
Examination of dissolved uranium concentrations in regional shallow groundwater relative to Operable Unit 8 of the Denver Radium Superfund Site
A radium industry existed between about 1914 and 1920 in Denver, Colorado, with operations located along the South Platte River. Sites associated with that industry were contaminated with radium and uranium processing residues and were incorporated into clean-up efforts as Operating Units (OUs) of the Denver Radium Superfund Site. Concentrations of uranium exceeding the U.S. Environmental ProtectiAuthorsCarleton R. BernCharacterization of and temporal changes in groundwater quality of the Upper Black Squirrel Creek Basin, El Paso County, Colorado, 2018–20
In 2018–20, the U.S. Geological Survey, in cooperation with Upper Black Squirrel Creek Ground Water Management District, sampled 48 wells for Phase III of a multiphase plan investigating groundwater quality in the alluvial aquifer of the Upper Black Squirrel Creek Basin (UBSB), El Paso County, Colorado. Results for samples collected from October to December each year were used to assess spatial anAuthorsZachary D. Kisfalusi, Nancy J. Bauch, Carleton R. BernLaboratory simulation of groundwater along uranium-mining-affected flow paths near the Grand Canyon, Arizona, USA
Mining of volumetrically small, but relatively enriched (average 0.6% U3O8) breccia pipe uranium (BPU) deposits near the Grand Canyon, Arizona, USA has the potential to affect groundwater and springs in the area. Such deposits also contain base metal sulfides that can oxidize to generate acid mine drainage and release trace metals. In this study, sequential batch experiments were conducted to simuAuthorsCarleton R. Bern, Kate M. Campbell, Katherine Walton-Day, Bradley S. Van GosenWater–rock interaction and the concentrations of major, trace, and rare earth elements in hydrocarbon-associated produced waters of the United States
Studies of co-produced waters from hydrocarbon extraction across multiple energy-producing basins have generally focused on major ions or a few select tracers, and studies that examine trace elements and involve laboratory experiments have generally been basin specific. Here, new perspective is sought through a broad analysis of concentration data for 26 elements from three hydrocarbon well typesAuthorsCarleton R. Bern, Justin E. Birdwell, Aaron M. JubbNontuberculous mycobacterial disease and molybdenum in Colorado watersheds
Nontuberculous mycobacteria (NTM) are environmental bacteria that may cause chronic lung disease. Environmental factors that favor NTM growth likely increase the risk of NTM exposure within specific environments. We aimed to identify water-quality constituents (Al, As, Cd, Ca, Cu, Fe, Pb, Mg, Mn, Mo, Ni, K, Se, Na, Zn, and pH) associated with NTM disease across Colorado watersheds. We conducted aAuthorsEttie M Lipner, Joshua French, Carleton R. Bern, Katherine Walton-Day, David Knox, Michael Strong, D. Rebecca Prevots, James L CrooksSalt flushing, salt storage, and controls on selenium: A 31-year mass-balance analysis of an irrigated, semiarid valley
Salinity, selenium, and uranium pose water‐quality challenges for the Arkansas River in southeastern Colorado and other rivers that support irrigation in semiarid regions. This study used 31 years of continuous discharge and specific conductance (SC) monitoring data to assess interannual patterns in water quality using mass balance on a 120‐km reach of river. Discrete sampling data were used to liAuthorsCarleton R. Bern, Michael J. Holmberg, Zachary D. KisfalusiEffects of John Martin Reservoir on water quality and quantity: Assessment by chemical, isotopic, and mass-balance methods
Water quality and quantity can be influenced by transit through and storage in reservoirs. Assessing such effects can be challenging, however, because of mixing and residence times, and inter-annual net storage and release from both the reservoir itself and surrounding porosity. Here, different methodologies were used to assess the effect of John Martin Reservoir (JMR), located on the Arkansas RivAuthorsCarleton R. Bern, Michael J. Holmberg, Zachary D. KisfalusiComment on “Particle fluxes in groundwater change subsurface rock chemistry over geologic time”
Over the last decade, studies at the Shale Hills Critical Zone Observatory (Shale Hills) have greatly expanded knowledge of weathering in previously understudied, shale-mantled terrains, as well as Earth's Critical Zone as a whole. Among the many discoveries made was the importance of redistribution and losses of micron-sized particles during development of shale-derived soils. A geochemical fingeAuthorsCarleton R. Bern, Tiffany YesavageImproved enrichment factor calculations through principal component analysis: Examples from soils near breccia pipe uranium mines, Arizona, USA
The enrichment factor (EF) is a widely used metric for determining how much the presence of an element in a sampling media has increased relative to average natural abundance because of human activity. Calculation of an EF requires the selection of both a background composition and a reference element, choices that can strongly influence the result of the calculation. Here, it is shown how carefulAuthorsCarleton R. Bern, Katherine Walton-Day, David L. NaftzDual-phase mass balance modeling of small mineral particle losses from sedimentary rock-derived soils
Losses of small mineral particles can be a significant physical process that affects the elemental composition of soils derived from sedimentary rocks. Shales, in particular, contain abundant clay-sized minerals that can be mobilized by simple disaggregation, and solutional weathering is limited because the parent rock is composed primarily of recalcitrant minerals previously subjected to continenAuthorsCarleton R. Bern, Tiffany YesavageColloid mobilization and seasonal variability in a semiarid headwater stream
Colloids can be important vectors for the transport of contaminants in the environment, but little is known about colloid mobilization at the watershed scale. We present colloid concentration, composition, and flux data over a large range of hydrologic conditions from a small watershed (Gordon Gulch) in the foothills of the Colorado Front Range. Colloids, consisting predominantly of Si, Fe, and AlAuthorsTaylor J. Mills, Suzanne P. Ancerson, Carleton R. Bern, Arnulfo Aguirre, Louis A. DerryIron isotope systematics of shale-derived soils as potentially influenced by small mineral particle loss
Loss of small mineral particles from soil has been suggested as a process that can produce net isotopic fractionation in the remaining soil. We extracted water dispersible colloids (WDCs) from bulk soil collected at the Susquehanna/Shale Hills Critical Zone Observatory (SSHO) and measured their Fe isotopic composition for comparison to published data from the site. The goal was to explain soil δ56AuthorsCarleton R. Bern, Tiffany Yesavage, Michael Pribil - Multimedia