View looking south down Kanab Creek toward the Grand Canyon and the Colorado River in the distance.
Katie Walton-Day
Katie is a Research Hydrologist with the USGS Colorado Water Science Center.
Katie is a research hydrologist and has worked at the U.S. Geological Survey located in Denver, Colorado for over 35 years. During this time her research has primarily focused on understanding the sources and mobility of trace metals associated with hard rock and uranium mineral deposits primarily in the western United States. A primary goal of her research is to provide science-based information to facilitate decisions about remediation in areas contaminated by historic mining practices. Recently she has begun developing communication products to broaden the audience for USGS scientific studies related to the environmental effects of uranium mining in the Grand Canyon region. Finally, her research has expanded into understanding the effects of harmful algal blooms in Colorado Reservoirs.
Professional Experience
1981-1983 – Exploration Geochemist, Anaconda Minerals Company
1983-1991 – Physical Scientist, U.S. Geological Survey
1991-1996 – Hydrologist, U.S. Geological Survey
1996-Present – Research Hydrologist, U.S. Geological Survey
Education and Certifications
PhD. Geology Colorado School of Mines, 1991
MS Geology Colorado School of Mines, 1985
BA Geology Smith College, 1981
Science and Products
Minerals Science Team
Upper Arkansas River Basin Toxics and Synoptic Studies
Gold King Mine release (2015): USGS water-quality data and activities
Watershed Contamination from Hard Rock Mining
U.S. Geological Survey Develops Approach to Assess Baseline Chemical and Radiological Conditions Prior to Uranium Mining near Grand Canyon National Park
Metal Concentrations and Loads in Leavenworth Creek, Colorado
Upper Arkansas Toxic-Substances Hydrology
Sources of Metal Loading to the Lake Fork from Turquoise Lake to the confluence with the Arkansas River
Effects of Fluvial Tailings Deposits on Receiving Waters in the Upper Arkansas River Basin, Lake County, Colorado
Upper Animas River Basin Abandoned Mine Lands Initiative
GIS data and scripts for Colorado Legacy Mine Lands Watershed Delineation and Scoring tool (WaDeS)
Concentration Data for 12 Elements of Concern Used in the Development of Surrogate Models for Estimating Elemental Concentrations in Surface Water of Three Hydrologic Basins (Delaware River, Illinois River and Upper Colorado River)
Geochemistry and Environmental Tracer Data for Groundwater, Stream Water, and Soil and Sediment from North Quartz Creek, Colorado
Water-quality data for stream and hyporheic zone samples altered by injection of sodium bromide tracer during a synoptic-sampling study, Leavenworth Creek, Clear Creek County, Colorado, 2012
Stream discharge, sodium, bromide, and specific conductance data for stream and hyporheic zone samples affected by injection of sodium bromide tracer, Leavenworth Creek, Clear Creek County, Colorado, August 2012
Geochemical data from batch experiments to test mobility of trace elements downgradient from breccia-pipe uranium deposits
Soil sample data for four uranium mine sites, Mohave County, Arizona, April and November 2018
Water quality and discharge data from draining mine tunnels near Silverton, Colorado 1993-2015
Surrogate regression models for computation of time series suspended-sediment concentrations at Muddy Creek above Paonia Reservoir, Anthracite Creek above mouth near Somerset, and North Fork Gunnison below Raven Gulch near Somerset, Colorado
Surface Materials Data from Breccia-Pipe Uranium Mine and Reference Sites, Arizona, USA
View looking south down Kanab Creek toward the Grand Canyon and the Colorado River in the distance.
USGS scientists collecting soil samples at Canyon Mine.
USGS scientists collecting soil samples at Canyon Mine.
Mechanisms of water-rock interaction and implications for remediating flooded mine workings elucidated from environmental tracers, stable isotopes, and rare earth elements
The truth is in the stream: Use of tracer techniques and synoptic sampling to evaluate metal loading and remedial options in a hydrologically complex setting
Opportunities to improve water quality during abandoned mine-tunnel reclamation
Incorporating streambank wells in stream mass loading studies to more effectively identify sources of solutes in stream water
Geoenvironmental model for roll-type uranium deposits in the Texas Gulf Coast
A novel method for conducting a geoenvironmental assessment of undiscovered ISR-amenable uranium Resources: Proof-of-concept in the Texas Coastal Plain
Laboratory simulation of groundwater along uranium-mining-affected flow paths near the Grand Canyon, Arizona, USA
Development and description of a composite hydrogeologic framework for inclusion in a geoenvironmental assessment of undiscovered uranium resources in Pliocene- to Pleistocene-age geologic units of the Texas Coastal Plain
Quantification of metal loading using tracer dilution and instantaneous synoptic sampling and importance of diel cycling in Leavenworth Creek, Clear Creek County, Colorado, 2012
Water-quality change following remediation using structural bulkheads in abandoned draining mines, upper Arkansas River and upper Animas River, Colorado USA
Nontuberculous mycobacterial disease and molybdenum in Colorado watersheds
Improved enrichment factor calculations through principal component analysis: Examples from soils near breccia pipe uranium mines, Arizona, USA
Non-USGS Publications**
**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.
Colorado Legacy Mine Lands Watershed Delineation and Scoring tool (WaDeS)
This web application, a summarized compilation of central Colorado water chemistry datasets from USGS and EPA, identifies legacy mine sites within the headwaters of central Colorado that could be good candidates for future remediation work based on stream metal concentrations, the number and complexity of mine features, and the potential for high natural background metal concentrations.
Informing Future Decision Making on Uranium Mining in Arizona: Science for Health and Environment
The USGS is conducting research at uranium-bearing breccia pipe deposits to address data gaps related to the potential effects of uranium exploration and mining activities on the Grand Canyon watershed, its people, wildlife, and water resources. Study locations are primarily on Federal lands with a few locations on Tribal lands, and include historic and active mines.
Science and Products
- Science
Minerals Science Team
The Minerals Integrated Science Team focuses on contaminant exposures in the environment that might originate from mineral resource activities including, transportation, storage, extraction and waste management. Perceived health risks to humans and other organisms will be distinguished from actual risks, if any. If actual risks are identified the science produced by this team can inform how to...Upper Arkansas River Basin Toxics and Synoptic Studies
From 1986 to 2001, the Upper Arkansas Toxics Project focused on metal transport in streams affected by mining. Studies were conducted to quantify the physical, chemical, and biological processes affecting trace metal fate and transport.Gold King Mine release (2015): USGS water-quality data and activities
On August 5, 2015, U.S. EPA was conducting an investigation of the Gold King Mine near Silverton, Colorado. While excavating as part of the investigation, water began leaking from the mine tunnel, and about three million gallons of water and sediment were released into Cement Creek, a tributary of the Animas River. The USGS provided pre- and post-release water-quality and streamflow data from...Watershed Contamination from Hard Rock Mining
Since 1986, the USGS Hard-Rock Mining Toxic-Substances Hydrology Project has focused on metal transport in streams affected by mining. Tracer-injection studies in St. Kevin Gulch, near Leadville, Colorado, helped the USGS design methods to characterize loading from mining activities on a watershed scale. Tracer-injection studies were done in 1995, in support of the planning needs of ederal Land...U.S. Geological Survey Develops Approach to Assess Baseline Chemical and Radiological Conditions Prior to Uranium Mining near Grand Canyon National Park
U.S. Geological Survey (USGS) scientists developed an approach and collected baseline data to quantitatively assess offsite migration of mine-related contaminants and to identify critical contaminant exposure pathways that could result from uranium mining activities in the Grand Canyon region.Metal Concentrations and Loads in Leavenworth Creek, Colorado
Metal loading from abandoned mines and groundwater in Leavenworth Creek causes aquatic life water-quality standards to be exceeded at the mouth of Leavenworth Creek.Upper Arkansas Toxic-Substances Hydrology
Since 1986, the USGS Hard-Rock Mining Toxic-Substances Hydrology Project has focused on metal transport in streams affected by mining. Tracer-injection studies in St. Kevin Gulch, near Leadville, Colorado, helped the USGS design methods to characterize loading from mining activities on a watershed scale. Tracer-injection studies were done in 1995, in support of the planning needs of ederal Land...Sources of Metal Loading to the Lake Fork from Turquoise Lake to the confluence with the Arkansas River
The Lake Fork emerges from the outlet of Turquoise Lake at the Sugarloaf dam and flows approximately 5 miles before joining the upper Arkansas River. The first reach of the Lake Fork downstream from the dam is affected by drainage from abandoned mines in the Sugarloaf mining district. Whereas remediation of some of the mine sites has been initiated, Federal Land holders are interested in assessing...Effects of Fluvial Tailings Deposits on Receiving Waters in the Upper Arkansas River Basin, Lake County, Colorado
Fluvial tailings deposits stored in the floodplain of the upper Arkansas River represent a potential nonpoint source of contamination to surface and ground waters. The U.S. Geological Survey has been cooperating with the U.S. Environmental Protection Agency to monitor a lowcost, insitu remediation technique for the deposits.Upper Animas River Basin Abandoned Mine Lands Initiative
The USGS Abandoned Mine Lands Initiative (AMLI) is developing and demonstrating scientific knowledge and technologies that will help Federal land management agencies clean up contamination in areas near abandoned hardrock mines across the Nation. The Initiative is being conducted in two pilot watersheds, the Upper Animas River Basin in Colorado and the Boulder River watershed in Montana, where the... - Data
GIS data and scripts for Colorado Legacy Mine Lands Watershed Delineation and Scoring tool (WaDeS)
This data release includes GIS datasets supporting the Colorado Legacy Mine Lands Watershed Delineation and Scoring tool (WaDeS), a web mapping application available at https://geonarrative.usgs.gov/colmlwades/. Water chemistry data were compiled from the U.S. Geological Survey (USGS) National Water Information System (NWIS), U.S. Environmental Protection Agency (EPA) STORET database, and the USGSConcentration Data for 12 Elements of Concern Used in the Development of Surrogate Models for Estimating Elemental Concentrations in Surface Water of Three Hydrologic Basins (Delaware River, Illinois River and Upper Colorado River)
The release of metals (or metalloids) to surface water can involve both natural and anthropogenic sources. Elevated metals concentrations can pose a risk to human health, wildlife, and ecosystem health, with the modes of toxicity and extent of risk varying as a function of the specific metal, its chemical form and the matrix with which it is associated (for example, dissolved versus particulate).Geochemistry and Environmental Tracer Data for Groundwater, Stream Water, and Soil and Sediment from North Quartz Creek, Colorado
This U.S. Geological Survey (USGS) data release contains data from stream water, groundwater, and soil samples collected in 2019 and 2020 in the North Quartz Creek watershed in central Colorado. Fourteen streambank wells were installed in pairs at seven locations in August 2020 to capture the emerging groundwater from the left bank and right banks (relative to downstream-facing direction) and a syWater-quality data for stream and hyporheic zone samples altered by injection of sodium bromide tracer during a synoptic-sampling study, Leavenworth Creek, Clear Creek County, Colorado, 2012
Leavenworth Creek, a tributary of South Clear Creek and Clear Creek near Georgetown, Colorado contains copper, lead, and zinc concentrations that are near to or exceed aquatic life standards. The creek drains the Argentine mining district where mining was active primarily in the early 1900s. In the summer of 2012, the U.S. Geological Survey (USGS) conducted a metal-loading study using tracer diluStream discharge, sodium, bromide, and specific conductance data for stream and hyporheic zone samples affected by injection of sodium bromide tracer, Leavenworth Creek, Clear Creek County, Colorado, August 2012
Leavenworth Creek, a tributary of South Clear Creek and Clear Creek near Georgetown, Colorado contains copper, lead, and zinc concentrations that are near to or exceed aquatic life standards. The creek drains the Argentine mining district where mining was active primarily in the early 1900s. In the summer of 2012, the U.S. Geological Survey (USGS) conducted a metal-loading study using tracer dilutGeochemical 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 mSoil sample data for four uranium mine sites, Mohave County, Arizona, April and November 2018
This U.S. Geological Survey data release is a spreadsheet containing soil-profile measurements of ambient spring and fall water-potential and water-content conditions, and physical and chemical properties for four mine sites, Mohave County, Arizona, April and November 2018. The four mines sampled in both April and November were Kanab North (native soil and reclaimed soil), EZ2 (native soil), ArizoWater quality and discharge data from draining mine tunnels near Silverton, Colorado 1993-2015
The American Tunnel, the Black Hawk mine, the Gold King mine, the Mogul mine, and the Red and Bonita mine are located in the Cement Creek watershed, tributary to the upper Animas River near Silverton, Colorado. All five sites have tunnels that drain groundwater from abandoned underground mine workings to the surface. This draining water has elevated concentrations of metals and degrades water qualSurrogate regression models for computation of time series suspended-sediment concentrations at Muddy Creek above Paonia Reservoir, Anthracite Creek above mouth near Somerset, and North Fork Gunnison below Raven Gulch near Somerset, Colorado
This model archive summary documents the surrogate regression model used to compute suspended-sediment concentrations at Muddy Creek above Paonia Reservoir, CO, USGS site number 385903107210800. The methods used follow U.S. Geological Survey (USGS) guidance as referenced in relevant Office of Surface Water Technical Memorandum (TM) 2016.07 and Office of Water Quality TM 2016.10, and USGS TechniqueSurface 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 - Multimedia
View Down Kanab Creek
View looking south down Kanab Creek toward the Grand Canyon and the Colorado River in the distance.
View looking south down Kanab Creek toward the Grand Canyon and the Colorado River in the distance.
Canyon Mine SamplingUSGS scientists collecting soil samples at Canyon Mine.
USGS scientists collecting soil samples at Canyon Mine.
- Publications
Filter Total Items: 65
Mechanisms of water-rock interaction and implications for remediating flooded mine workings elucidated from environmental tracers, stable isotopes, and rare earth elements
Contamination from acid mine drainage affects ecosystems and usability of groundwater for domestic and municipal purposes. The Captain Jack Superfund Site outside of Ward, Boulder County, Colorado, USA, hosts a draining mine adit that was remediated through emplacement of a hydraulic bulkhead to preclude acid mine drainage from entering nearby Lefthand Creek. During impoundment of water within theAuthorsConnor P. Newman, Katherine Walton-Day, Robert L. Runkel, Richard WilkinThe truth is in the stream: Use of tracer techniques and synoptic sampling to evaluate metal loading and remedial options in a hydrologically complex setting
Two synoptic sampling campaigns were conducted to quantify metal loading to Illinois Gulch, a small stream affected by historical mining activities. The first campaign was designed to determine the degree to which Illinois Gulch loses water to the underlying mine workings, and to determine the effect of these losses on observed metal loads. The second campaign was designed to evaluate metal loadinAuthorsRobert L. Runkel, Philip Verplanck, Katherine Walton-Day, R. Blaine McCleskey, Patrick ByrneOpportunities to improve water quality during abandoned mine-tunnel reclamation
In the western United States, bulkheads are constructed to limit drainage from abandoned, draining mine adits and to protect downstream resources from uncontrolled releases of degraded adit water. Although bulkheads improve safety and water-quality conditions at the mouth of the adit, elevated hydraulic pressure behind the bulkhead often causes continuing water-quality problems in new locations. SAuthorsKatherine Walton-Day, James J. Gusek, Connor P. NewmanIncorporating streambank wells in stream mass loading studies to more effectively identify sources of solutes in stream water
Stream synoptic sampling studies that include flow estimates derived from the stream tracer dilution method are now commonly performed to identify sources and processes controlling solute transport to streams. However, a limitation of this mass-loading approach is its inability to identify the side of the stream on which a source is located in the common case where loading is largely from groundwaAuthorsAndrew H. Manning, Robert L. Runkel, Jean Morrison, Richard Wanty, Katherine Walton-DayGeoenvironmental model for roll-type uranium deposits in the Texas Gulf Coast
Geoenvironmental models were formulated by the U.S. Geological Survey in the 1990s to describe potential environmental effects of extracting different types of ore deposits in different geologic and climatic regions. This paper presents a geoenvironmental model for roll-front (roll-type) uranium deposits in the Texas Coastal Plain. The model reviews descriptive and quantitative information derivedAuthorsKatherine Walton-Day, Johanna Blake, Robert R. Seal, Tanya J. Gallegos, Jean Dupree, Kent D BecherA novel method for conducting a geoenvironmental assessment of undiscovered ISR-amenable uranium Resources: Proof-of-concept in the Texas Coastal Plain
A geoenvironmental assessment methodology was developed to estimate waste quantities and disturbances that could be associated with the extraction of undiscovered uranium resources and identify areas on the landscape where uranium and other constituents of potential concern (COPCs) that may co-occur with uranium deposits in this region are likely to persist, if introduced into the environment. PriAuthorsTanya J. Gallegos, Victoria G. Stengel, Katherine Walton-Day, Johanna Blake, Andrew Teeple, Delbert G Humberson, Steven M. Cahan, Douglas Yager, Kent D BecherLaboratory 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 GosenDevelopment and description of a composite hydrogeologic framework for inclusion in a geoenvironmental assessment of undiscovered uranium resources in Pliocene- to Pleistocene-age geologic units of the Texas Coastal Plain
A previously completed mineral resources assessment of the Texas Coastal Plain indicated the potential for the future discovery of uranium resources. Geoenvironmental assessments that include the hydrogeologic framework can be used as a tool to understand the potential effects of mining operations. The hydrogeologic framework for this study focused on the composite hydrogeologic unit of the tractAuthorsAndrew Teeple, Kent D Becher, Katherine Walton-Day, Delbert G Humberson, Tanya J. GallegosQuantification of metal loading using tracer dilution and instantaneous synoptic sampling and importance of diel cycling in Leavenworth Creek, Clear Creek County, Colorado, 2012
Leavenworth Creek, a tributary of South Clear Creek and Clear Creek near Georgetown, Colorado, contains copper, lead, and zinc at concentrations close to or in excess of aquatic-life standards. In the summer of 2012, the U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service and the Colorado Division of Reclamation, Mining and Safety, conducted monitoring toAuthorsKatherine Walton-Day, Robert L. Runkel, Christin D. Smith, Briant A. KimballWater-quality change following remediation using structural bulkheads in abandoned draining mines, upper Arkansas River and upper Animas River, Colorado USA
Water-quality effects after remediating abandoned draining mine tunnels using structural bulkheads were examined in two study areas in Colorado, USA. A bulkhead was installed in the Dinero mine tunnel in 2009 to improve water quality in Lake Fork Creek, a tributary to the upper Arkansas River. Although bulkhead installation improved pH, and manganese and zinc concentrations and loads at the DineroAuthorsKatherine Walton-Day, Alisa Mast, Robert L. RunkelNontuberculous 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 CrooksImproved 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. NaftzNon-USGS Publications**
Day, K.W., 1986, Determination of processes controlling vertical trace element distribution in Filson Creek bog, Lake County, Minnesota: Golden, Colorado School of Mines, M.S. thesis # 3149, 236 p.Walton-Day, Katherine, 1991, Hydrology and geochemistry of a natural wetland affected by acid mine drainage, St. Kevin Gulch, Lake County, Colorado: Golden, Colorado School of Mines, Ph.D. dissertation # 4033, 299 p.**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.
- Web Tools
Colorado Legacy Mine Lands Watershed Delineation and Scoring tool (WaDeS)
This web application, a summarized compilation of central Colorado water chemistry datasets from USGS and EPA, identifies legacy mine sites within the headwaters of central Colorado that could be good candidates for future remediation work based on stream metal concentrations, the number and complexity of mine features, and the potential for high natural background metal concentrations.
Informing Future Decision Making on Uranium Mining in Arizona: Science for Health and Environment
The USGS is conducting research at uranium-bearing breccia pipe deposits to address data gaps related to the potential effects of uranium exploration and mining activities on the Grand Canyon watershed, its people, wildlife, and water resources. Study locations are primarily on Federal lands with a few locations on Tribal lands, and include historic and active mines.
- News