Fred D Tillman, Jr., Ph.D.
Fred Tillman joined the USGS Arizona Water Science Center in Tucson, AZ in 2006 after two-plus years as a National Research Council (NRC) fellow with the USEPA Office of Research and Development (ORD) in Athens, Georgia.
Prior to joining the USGS, Fred was a post-doctoral researcher with the Ecosystems Research Division of USEPA’s ORD from 2004 through mid-2006, working with Dr. James W. Weaver on issues related to soil vapor intrusion, particularly from leaking underground storage tanks. Fred joined EPA after completion of his doctoral degree in Environmental Engineering at the University of Virginia in 2003, where he worked with Dr. James A. Smith on the response of volatile organic compound (VOC) vapors in the unsaturated zone to natural barometric pressure fluctuations (barometric pumping).
Education and Certifications
Ph.D. 2003, Environmental Engineering, University of Virginia, Charlottesville, VA
M.S. 1998, Environmental Engineering, University of Virginia, Charlottesville, VA
B.S. 1990, Electrical Engineering, Florida State University, Tallahassee, FL
Science and Products
Filter Total Items: 46
Investigation of total and hexavalent chromium in filtered and unfiltered groundwater samples at the Tucson International Airport Superfund Site Investigation of total and hexavalent chromium in filtered and unfiltered groundwater samples at the Tucson International Airport Superfund Site
Potential health effects from hexavalent chromium in groundwater have recently become a concern to regulators at the Tucson International Airport Area Superfund site. In 2016, the U.S. Geological Survey sampled 46 wells in the area to characterize the nature and extent of chromium in groundwater, to understand what proportion of total chromium is in the hexavalent state, and to determine...
Authors
Fred D. Tillman, R. Blaine McCleskey, Edyth Hermosillo
Initial characterization of the groundwater system near the Lower Colorado Water Supply Project, Imperial Valley, California Initial characterization of the groundwater system near the Lower Colorado Water Supply Project, Imperial Valley, California
In 2009, the U.S. Geological Survey, in cooperation with the city of Needles, began a study of the hydrogeology along the All-American Canal, which conveys water from the Colorado River to the Imperial Valley. The focus of this study was to gain a better understanding of the effect of lining the All-American Canal, and other management actions, on future total dissolved solids...
Authors
Alissa L. Coes, Michael Land, Jill N. Densmore, Michael T. Landrum, Kimberly R. Beisner, Jeffrey R. Kennedy, Jamie P. Macy, Fred D. Tillman
A comparison of estimates of basin-scale soil-moisture evapotranspiration and estimates of riparian groundwater evapotranspiration with implications for water budgets in the Verde Valley, Central Arizona, USA A comparison of estimates of basin-scale soil-moisture evapotranspiration and estimates of riparian groundwater evapotranspiration with implications for water budgets in the Verde Valley, Central Arizona, USA
Population growth in the Verde Valley in Arizona has led to efforts to better understand water availability in the watershed. Evapotranspiration (ET) is a substantial component of the water budget and a critical factor in estimating groundwater recharge in the area. In this study, four estimates of ET are compared and discussed with applications to the Verde Valley. Higher potential ET...
Authors
Fred D. Tillman, Stephen M. Wiele, Donald R. Pool
Documentation of input datasets for the soil-water balance groundwater recharge model of the Upper Colorado River Basin Documentation of input datasets for the soil-water balance groundwater recharge model of the Upper Colorado River Basin
The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating more than 4.5 million acres of farmland, and generating about 12 billion kilowatt hours of hydroelectric power annually. The Upper Colorado River Basin, encompassing more than 110,000 square miles (mi2), contains the headwaters of the Colorado...
Authors
Fred D. Tillman
The Effect of modeled recharge distribution on simulated groundwater availability and capture The Effect of modeled recharge distribution on simulated groundwater availability and capture
Simulating groundwater flow in basin-fill aquifers of the semiarid southwestern United States commonly requires decisions about how to distribute aquifer recharge. Precipitation can recharge basin-fill aquifers by direct infiltration and transport through faults and fractures in the high-elevation areas, by flowing overland through high-elevation areas to infiltrate at basin-fill margins...
Authors
Fred D. Tillman, Donald R. Pool, Stanley A. Leake
Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin
Study region The study region encompasses the Upper Colorado River Basin (UCRB), which provides water for 40 million people and is a vital part of the water supply in the western U.S. Study focus Groundwater and surface water can be considered a single water resource and thus it is important to understand groundwater contributions to streamflow, or baseflow, within a region. Previously
Authors
Christine Rumsey, Matthew P. Miller, David D. Susong, Fred D. Tillman, David W. Anning
Geospatial datasets for assessing the effects of rangeland conditions on dissolved-solids yields in the Upper Colorado River Basin Geospatial datasets for assessing the effects of rangeland conditions on dissolved-solids yields in the Upper Colorado River Basin
In 2009, the U.S. Geological Survey (USGS) developed a Spatially Referenced Regressions on Watershed Attributes (SPARROW) surface-water quality model for the Upper Colorado River Basin (UCRB) relating dissolved-solids sources and transport in the 1991 water year to upstream catchment characteristics. The SPARROW model focused on geologic and agricultural sources of dissolved solids in...
Authors
Fred D. Tillman, Marilyn E. Flynn, David W. Anning
Water-chemistry data collected in and near Kaloko-Honokohau National Historical Park, Hawaii, 2012–2014 Water-chemistry data collected in and near Kaloko-Honokohau National Historical Park, Hawaii, 2012–2014
Kaloko-Honokōhau National Historical Park (KAHO) on western Hawaiʻi was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities, including the preservation of a variety of culturally and ecologically significant water resources that are vital to this mission. KAHO water bodies provide habitat for 1 threatened, 11 endangered, and 3...
Authors
Fred D. Tillman, Delwyn S. Oki, Adam G. Johnson
Updated estimates of long-term average dissolved-solids loading in streams and rivers of the Upper Colorado River Basin Updated estimates of long-term average dissolved-solids loading in streams and rivers of the Upper Colorado River Basin
The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating over 4.5 million acres of farmland, and annually generating about 12 billion kilowatt hours of hydroelectric power. The Upper Colorado River Basin, part of the Colorado River Basin, encompasses more than 110,000 mi2 and is the source of much...
Authors
Fred D. Tillman, David W. Anning
A data reconnaissance on the effect of suspended-sediment concentrations on dissolved-solids concentrations in rivers and tributaries in the Upper Colorado River Basin A data reconnaissance on the effect of suspended-sediment concentrations on dissolved-solids concentrations in rivers and tributaries in the Upper Colorado River Basin
The Colorado River is one of the most important sources of water in the western United States, supplying water to over 35 million people in the U.S. and 3 million people in Mexico. High dissolved-solids loading to the River and tributaries are derived primarily from geologic material deposited in inland seas in the mid-to-late Cretaceous Period, but this loading may be increased by human
Authors
Fred D. Tillman, David W. Anning
Investigation of geochemical indicators to evaluate the connection between inland and coastal groundwater systems near Kaloko-Honokōhau National Historical Park, Hawai‘i Investigation of geochemical indicators to evaluate the connection between inland and coastal groundwater systems near Kaloko-Honokōhau National Historical Park, Hawai‘i
Kaloko-Honokōhau National Historical Park (KAHO) is a coastal sanctuary on the western side of the Island of Hawai‘i that was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities. KAHO contains a variety of culturally and ecologically significant water resources and water-related habitat for species that have been declared as...
Authors
Fred D. Tillman, Delwyn S. Oki, Adam G. Johnson, Larry B. Barber, Kimberly R. Beisner
Preliminary groundwater flow model of the basin-fill aquifers in Detrital, Hualapai, and Sacramento Valleys, Mohave County, northwestern Arizona Preliminary groundwater flow model of the basin-fill aquifers in Detrital, Hualapai, and Sacramento Valleys, Mohave County, northwestern Arizona
Preliminary numerical models were developed to simulate groundwater flow in the basin-fill alluvium in Detrital, Hualapai, and Sacramento Valleys in northwestern Arizona. The purpose of this exercise was to gather and evaluate available information and data, to test natural‑recharge concepts, and to indicate directions for improving future regional groundwater models of the study area...
Authors
Fred D. Tillman, Bradley D. Garner, Margot Truini
Non-USGS Publications**
Tillman, F.D and Weaver, J.W., 2007, Parameter sets for upper and lower bounds on soil-to-indoor-air contaminant attenuation predicted by the Johnson and Ettinger vapor intrusion model. Atmospheric Environment, 41, no. 27, p. 5797–5806.
Tillman, F.D and Weaver, J.W., 2007, Temporal moisture content variability beneath and external to a building and the potential effects on vapor intrusion risk assessment. Science of the Total Environment, 379, no. 1, p. 1-15.
Tillman, F.D and Weaver, J.W., 2006, Uncertainty from synergistic effects of multiple parameters in the Johnson and Ettinger (1991) vapor intrusion model. Atmospheric Environment, 40, no. 22, p. 4098–4112.
Tillman, F.D and Weaver, J.W., 2005, Review of recent research on vapor intrusion. U.S. Environmental Protection Agency Publication No. EPA/600/R-05/106, 40 p.
Weaver, J.W. and Tillman, F.D, 2005, Uncertainty and the Johnson-Ettinger model for vapor intrusion calculations. U.S. Environmental Protection Agency Publication No. EPA/600/R-05/110, 43 p.
Tillman, F.D and Smith, J.A., 2005, Vapor transport in the unsaturated zone, in Lehr, J.H., and Keely, J., eds., Water Encyclopedia: Ground Water. New Jersey, John Wiley & Sons, p. 543–548
Tillman, F.D and Smith, J.A., 2005, Site characteristics controlling airflow in the shallow unsaturated zone at Picatinny Arsenal, NJ. Environmental Engineering Science, 22, no. 1, p. 25–37.
Tillman, F.D, Bartelt-Hunt, S.L., Craver, V.A, Smith, J.A., and Alther, G.R., 2005, Relative metal ion sorption on natural and engineered sorbents: Batch and column studies. Environmental Engineering Science, 22. no. 3, p. 400–410.
Alther, G.R., Tillman, F.D, and Smith, J.A., 2005, Evaluation of Two Organoclays, Clinoptilolite, and Hydroxy-Apatite as Sorbents for Heavy Metal Removal from Water, in Calabrese E.J., Kostecki P.T., Dragun J. (eds) Contaminated Soils, Sediments and Water. Springer, Boston, MA, p. 457–468.
Tillman, F.D, Bartelt-Hunt, S.L., Smith, J.A., and Alther, G.R., 2004, Evaluation of an organoclay, an organoclay-anthracite blend, clinoptilolite, and hydroxy-apatite as sorbents for heavy metal removal from water. Bulletin of Environmental Contamination and Toxicology, 72, no. 6, p. 1134–1141.
Tillman, F.D and Smith, J.A., 2004, Design and laboratory testing of a chamber device to measure total flux of volatile organic compounds from the unsaturated zone under natural conditions. Journal of Contaminant Hydrology, 75, no. 1-2, p. 71–94.
Tillman, F.D, Choi, J.-W., and Smith, J.A., 2003, A comparison of direct measurement and model simulation of total flux of volatile organic compounds from the subsurface to the atmosphere under natural field conditions. Water Resources Research, 39, no. 10, p. 1284–1294.
Choi, J.-W., Tillman, F.D, and Smith, J.A, 2002, Relative Importance of Gas-Phase Diffusive and Advective Trichloroethene (TCE) Fluxes in the Unsaturated Zone under Natural Conditions. Environmental Science and Technology, 36, no. 14, p. 3157–3164.
Olson, M.S., Tillman, F.D, Choi, J.-W., and Smith, J.A., 2001, Comparison of three techniques to measure unsaturated-zone air permeability at Picatinny Arsenal, New Jersey. Journal of Contaminant Hydrology, 53, no. 1-2, p. 1–19.
Tillman, F.D, Choi, J.-W., Katchmark, W., Smith, J. A., and Wood, H.G.III, 2001, Unsaturated-zone airflow: Implications for natural remediation of ground water by contaminant transport through the subsurface, in Smith, J.A., and Burns, S.E., eds., Physicochemical Groundwater Remediation. New York, Kluwer Academic/Plenum Publishing, ISBN 978-0-306-46928-2, p. 307–340.
**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: 46
Investigation of total and hexavalent chromium in filtered and unfiltered groundwater samples at the Tucson International Airport Superfund Site Investigation of total and hexavalent chromium in filtered and unfiltered groundwater samples at the Tucson International Airport Superfund Site
Potential health effects from hexavalent chromium in groundwater have recently become a concern to regulators at the Tucson International Airport Area Superfund site. In 2016, the U.S. Geological Survey sampled 46 wells in the area to characterize the nature and extent of chromium in groundwater, to understand what proportion of total chromium is in the hexavalent state, and to determine...
Authors
Fred D. Tillman, R. Blaine McCleskey, Edyth Hermosillo
Initial characterization of the groundwater system near the Lower Colorado Water Supply Project, Imperial Valley, California Initial characterization of the groundwater system near the Lower Colorado Water Supply Project, Imperial Valley, California
In 2009, the U.S. Geological Survey, in cooperation with the city of Needles, began a study of the hydrogeology along the All-American Canal, which conveys water from the Colorado River to the Imperial Valley. The focus of this study was to gain a better understanding of the effect of lining the All-American Canal, and other management actions, on future total dissolved solids...
Authors
Alissa L. Coes, Michael Land, Jill N. Densmore, Michael T. Landrum, Kimberly R. Beisner, Jeffrey R. Kennedy, Jamie P. Macy, Fred D. Tillman
A comparison of estimates of basin-scale soil-moisture evapotranspiration and estimates of riparian groundwater evapotranspiration with implications for water budgets in the Verde Valley, Central Arizona, USA A comparison of estimates of basin-scale soil-moisture evapotranspiration and estimates of riparian groundwater evapotranspiration with implications for water budgets in the Verde Valley, Central Arizona, USA
Population growth in the Verde Valley in Arizona has led to efforts to better understand water availability in the watershed. Evapotranspiration (ET) is a substantial component of the water budget and a critical factor in estimating groundwater recharge in the area. In this study, four estimates of ET are compared and discussed with applications to the Verde Valley. Higher potential ET...
Authors
Fred D. Tillman, Stephen M. Wiele, Donald R. Pool
Documentation of input datasets for the soil-water balance groundwater recharge model of the Upper Colorado River Basin Documentation of input datasets for the soil-water balance groundwater recharge model of the Upper Colorado River Basin
The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating more than 4.5 million acres of farmland, and generating about 12 billion kilowatt hours of hydroelectric power annually. The Upper Colorado River Basin, encompassing more than 110,000 square miles (mi2), contains the headwaters of the Colorado...
Authors
Fred D. Tillman
The Effect of modeled recharge distribution on simulated groundwater availability and capture The Effect of modeled recharge distribution on simulated groundwater availability and capture
Simulating groundwater flow in basin-fill aquifers of the semiarid southwestern United States commonly requires decisions about how to distribute aquifer recharge. Precipitation can recharge basin-fill aquifers by direct infiltration and transport through faults and fractures in the high-elevation areas, by flowing overland through high-elevation areas to infiltrate at basin-fill margins...
Authors
Fred D. Tillman, Donald R. Pool, Stanley A. Leake
Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin
Study region The study region encompasses the Upper Colorado River Basin (UCRB), which provides water for 40 million people and is a vital part of the water supply in the western U.S. Study focus Groundwater and surface water can be considered a single water resource and thus it is important to understand groundwater contributions to streamflow, or baseflow, within a region. Previously
Authors
Christine Rumsey, Matthew P. Miller, David D. Susong, Fred D. Tillman, David W. Anning
Geospatial datasets for assessing the effects of rangeland conditions on dissolved-solids yields in the Upper Colorado River Basin Geospatial datasets for assessing the effects of rangeland conditions on dissolved-solids yields in the Upper Colorado River Basin
In 2009, the U.S. Geological Survey (USGS) developed a Spatially Referenced Regressions on Watershed Attributes (SPARROW) surface-water quality model for the Upper Colorado River Basin (UCRB) relating dissolved-solids sources and transport in the 1991 water year to upstream catchment characteristics. The SPARROW model focused on geologic and agricultural sources of dissolved solids in...
Authors
Fred D. Tillman, Marilyn E. Flynn, David W. Anning
Water-chemistry data collected in and near Kaloko-Honokohau National Historical Park, Hawaii, 2012–2014 Water-chemistry data collected in and near Kaloko-Honokohau National Historical Park, Hawaii, 2012–2014
Kaloko-Honokōhau National Historical Park (KAHO) on western Hawaiʻi was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities, including the preservation of a variety of culturally and ecologically significant water resources that are vital to this mission. KAHO water bodies provide habitat for 1 threatened, 11 endangered, and 3...
Authors
Fred D. Tillman, Delwyn S. Oki, Adam G. Johnson
Updated estimates of long-term average dissolved-solids loading in streams and rivers of the Upper Colorado River Basin Updated estimates of long-term average dissolved-solids loading in streams and rivers of the Upper Colorado River Basin
The Colorado River and its tributaries supply water to more than 35 million people in the United States and 3 million people in Mexico, irrigating over 4.5 million acres of farmland, and annually generating about 12 billion kilowatt hours of hydroelectric power. The Upper Colorado River Basin, part of the Colorado River Basin, encompasses more than 110,000 mi2 and is the source of much...
Authors
Fred D. Tillman, David W. Anning
A data reconnaissance on the effect of suspended-sediment concentrations on dissolved-solids concentrations in rivers and tributaries in the Upper Colorado River Basin A data reconnaissance on the effect of suspended-sediment concentrations on dissolved-solids concentrations in rivers and tributaries in the Upper Colorado River Basin
The Colorado River is one of the most important sources of water in the western United States, supplying water to over 35 million people in the U.S. and 3 million people in Mexico. High dissolved-solids loading to the River and tributaries are derived primarily from geologic material deposited in inland seas in the mid-to-late Cretaceous Period, but this loading may be increased by human
Authors
Fred D. Tillman, David W. Anning
Investigation of geochemical indicators to evaluate the connection between inland and coastal groundwater systems near Kaloko-Honokōhau National Historical Park, Hawai‘i Investigation of geochemical indicators to evaluate the connection between inland and coastal groundwater systems near Kaloko-Honokōhau National Historical Park, Hawai‘i
Kaloko-Honokōhau National Historical Park (KAHO) is a coastal sanctuary on the western side of the Island of Hawai‘i that was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities. KAHO contains a variety of culturally and ecologically significant water resources and water-related habitat for species that have been declared as...
Authors
Fred D. Tillman, Delwyn S. Oki, Adam G. Johnson, Larry B. Barber, Kimberly R. Beisner
Preliminary groundwater flow model of the basin-fill aquifers in Detrital, Hualapai, and Sacramento Valleys, Mohave County, northwestern Arizona Preliminary groundwater flow model of the basin-fill aquifers in Detrital, Hualapai, and Sacramento Valleys, Mohave County, northwestern Arizona
Preliminary numerical models were developed to simulate groundwater flow in the basin-fill alluvium in Detrital, Hualapai, and Sacramento Valleys in northwestern Arizona. The purpose of this exercise was to gather and evaluate available information and data, to test natural‑recharge concepts, and to indicate directions for improving future regional groundwater models of the study area...
Authors
Fred D. Tillman, Bradley D. Garner, Margot Truini
Non-USGS Publications**
Tillman, F.D and Weaver, J.W., 2007, Parameter sets for upper and lower bounds on soil-to-indoor-air contaminant attenuation predicted by the Johnson and Ettinger vapor intrusion model. Atmospheric Environment, 41, no. 27, p. 5797–5806.
Tillman, F.D and Weaver, J.W., 2007, Temporal moisture content variability beneath and external to a building and the potential effects on vapor intrusion risk assessment. Science of the Total Environment, 379, no. 1, p. 1-15.
Tillman, F.D and Weaver, J.W., 2006, Uncertainty from synergistic effects of multiple parameters in the Johnson and Ettinger (1991) vapor intrusion model. Atmospheric Environment, 40, no. 22, p. 4098–4112.
Tillman, F.D and Weaver, J.W., 2005, Review of recent research on vapor intrusion. U.S. Environmental Protection Agency Publication No. EPA/600/R-05/106, 40 p.
Weaver, J.W. and Tillman, F.D, 2005, Uncertainty and the Johnson-Ettinger model for vapor intrusion calculations. U.S. Environmental Protection Agency Publication No. EPA/600/R-05/110, 43 p.
Tillman, F.D and Smith, J.A., 2005, Vapor transport in the unsaturated zone, in Lehr, J.H., and Keely, J., eds., Water Encyclopedia: Ground Water. New Jersey, John Wiley & Sons, p. 543–548
Tillman, F.D and Smith, J.A., 2005, Site characteristics controlling airflow in the shallow unsaturated zone at Picatinny Arsenal, NJ. Environmental Engineering Science, 22, no. 1, p. 25–37.
Tillman, F.D, Bartelt-Hunt, S.L., Craver, V.A, Smith, J.A., and Alther, G.R., 2005, Relative metal ion sorption on natural and engineered sorbents: Batch and column studies. Environmental Engineering Science, 22. no. 3, p. 400–410.
Alther, G.R., Tillman, F.D, and Smith, J.A., 2005, Evaluation of Two Organoclays, Clinoptilolite, and Hydroxy-Apatite as Sorbents for Heavy Metal Removal from Water, in Calabrese E.J., Kostecki P.T., Dragun J. (eds) Contaminated Soils, Sediments and Water. Springer, Boston, MA, p. 457–468.
Tillman, F.D, Bartelt-Hunt, S.L., Smith, J.A., and Alther, G.R., 2004, Evaluation of an organoclay, an organoclay-anthracite blend, clinoptilolite, and hydroxy-apatite as sorbents for heavy metal removal from water. Bulletin of Environmental Contamination and Toxicology, 72, no. 6, p. 1134–1141.
Tillman, F.D and Smith, J.A., 2004, Design and laboratory testing of a chamber device to measure total flux of volatile organic compounds from the unsaturated zone under natural conditions. Journal of Contaminant Hydrology, 75, no. 1-2, p. 71–94.
Tillman, F.D, Choi, J.-W., and Smith, J.A., 2003, A comparison of direct measurement and model simulation of total flux of volatile organic compounds from the subsurface to the atmosphere under natural field conditions. Water Resources Research, 39, no. 10, p. 1284–1294.
Choi, J.-W., Tillman, F.D, and Smith, J.A, 2002, Relative Importance of Gas-Phase Diffusive and Advective Trichloroethene (TCE) Fluxes in the Unsaturated Zone under Natural Conditions. Environmental Science and Technology, 36, no. 14, p. 3157–3164.
Olson, M.S., Tillman, F.D, Choi, J.-W., and Smith, J.A., 2001, Comparison of three techniques to measure unsaturated-zone air permeability at Picatinny Arsenal, New Jersey. Journal of Contaminant Hydrology, 53, no. 1-2, p. 1–19.
Tillman, F.D, Choi, J.-W., Katchmark, W., Smith, J. A., and Wood, H.G.III, 2001, Unsaturated-zone airflow: Implications for natural remediation of ground water by contaminant transport through the subsurface, in Smith, J.A., and Burns, S.E., eds., Physicochemical Groundwater Remediation. New York, Kluwer Academic/Plenum Publishing, ISBN 978-0-306-46928-2, p. 307–340.
**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.