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Mechanisms and models for colloid and colloid-facilitated transport and fate
Multiphase flow, transport, and interphase mass transfer processes in porous media
Numerical and analytic models
Development and design of animal waste management practices and treatments
Comprehensive nutrient management plans
Academic Degrees:
Ph.D.
Soil Science (Soil Physics), University of California, Riverside, 1995
Dissertation: Experimental and Theoretical Investigations of Multiphase Capillarity
M.S.
Soil Science (Soil Physics), University of California, Riverside, 1991
Thesis: Transient State Modeling of Various Irrigation Management Strategies
B.S.
Physics, Brigham Young University, 1989
Minors in Chemistry and Mathematics
Certified:
Passed the 8 hour NCEES Professional Civil Engineering Exam
Present and Past Positions:
2000-Present
Soil Scientist (GS-15)
USDA-ARS U.S. Salinity Laboratory Riverside, CA
1999
Adjunct Assistant Professor
Dept. of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI
1995-2000
Postdoctoral Positions (Assistant Research Scientist, Research Investigator, and Research Fellow)
Dept. of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI
Professional Research and Publications:
Dr. Bradford is a world renowned expert in the field of mechanisms and models to describe colloid (nanoparticles, microorganisms, and clays) and colloid-facilitated transport and fate in the environment. He has authored over 124 publications on a wide variety of topics in soil physics, contaminant hydrology, and environmental engineering. Most of these publications appeared in peer-reviewed journals. He has a Google Scholar H-factor of 45 (45 publications with more than 45 citations), and is first-author on 3 invited review papers.
Awards:
Excellence in Review Award, Environmental Science & Technology, 2012.
Fellow of the Soil Science Society of America.
Fellow of the American Society of Agronomy.
Research Grants:
Co-Principal investigator on proposals totaling more than $2.6 million.
Special Invitations:
Over 37 invited presentations to national and international audience, including 5 keynote addresses.
Professional Affiliations:
American Geophysical Union
American Society of Agronomy
Soil Science Society of America
Professional Service:
Editor in Chief for Critical Reviews of Environmental Science and Technology (2017-present), Technical Editor for Journal of Environmental Quality (JEQ, 2014-2016), Associate Editor (AE) for JEQ (2003-2006), and AE for Vadose Zone Journal (VZJ, 2004-2013).
Co-organizer of special issues in JEQ (2008 and 2015) and VZJ (2008), and sessions at annual meetings of SSSA (1997 and 2006) and AGU (2008, 2010, and 2011).
Co-organizer of conference entitled “Aerobic Spores and Other Microbial Indicators for Determining Groundwater Under the Direct Influence of Surface Water”. This conference was held in Riverside, CA on Sept. 6-8, 2016.
International Conference “Interfaces Against Pollution”, Advisory Committee, May 2004 - 2012.
Secretary (2005) and chair (2006) of the W1188 Multistate Research Project entitled “Characterizing Mass and Energy Transport at Different Scales”, USDA, CSREES.
USDA-ARS, National Program 206 (Manure and Byproduct Utilization) Planning Committee. April 13-15, 2004.
Co-team leader (with Yakov Pachepsky), NP 206, Manure and Byproduct Utilization, Pathogens problem area 2e, Modeling fate and transport of manure-borne pathogens from “pedon” to watershed scale. April, 2004-2009.
ASA and SSSA Fellows Committee 2014 and 2015.
University faculty promotion and tenure evaluation committees (3).
Dissertation evaluation and defense committees of 6 PhD students, and also informally supervised and mentored research activities of 7 other PhD students.
Reviewer for numerous technical journals (>21), funding organizations (7), proposal evaluation committees (2), and project advisor committees (3).
(Clicking on the reprint icon will take you to the publication reprint.)
Uncovering the gaps in managed aquifer recharge for sustainable groundwater management: A focus on hillslopes and mountains-(Peer Reviewed Journal) Meles, M.B., Bradford, S.A., Casillas-Trasvina, J.A., Chen, L., Osterman, G.K., Levers, L.R., Hatch, T., Ajami, H., Crompton, O.V., Kisekka, I. 2024. Uncovering the gaps in managed aquifer recharge for sustainable groundwater management: A focus on hillslopes and mountains. Critical Reviews in Environmental Science Technology. 639. https://doi.org/10.1016/j.jhydrol.2024.131615.
Virus transport from drywells under constant head conditions: a modeling study-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Simunek, J., Gerba, C.P., Kraemer, S.R. 2021. Virus transport from drywells under constant head conditions: a modeling study. Water Research. 197. Article 117040. https://doi.org/10.1016/j.watres.2021.117040.
Why are viruses spiked?-(Peer Reviewed Journal) Shen, C., Bradford, S.A. 2021. Why are viruses spiked? mSphere. 6(1). Article e01339-20. https://doi.org/10.1128/mSphere.01339-20.
Transdisciplinary contributions and opportunities in soil physical hydrology-(Peer Reviewed Journal) Wendroth, O., Bradford, S.A., Harter, T. 2021. Transdisciplinary contributions and opportunities in soil physical hydrology. Vadose Zone Journal. 20(2). Article e20114. https://doi.org/10.1002/vzj2.20114.
Comparison of simulated recharge from drywells and infiltration basins: a modeling study-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Simunek, J., Kraemer, S.R. 2020. Comparison of simulated recharge from drywells and infiltration basins: a modeling study. Journal of Hydrology. 594. Article 125720. https://doi.org/10.1016/j.jhydrol.2020.125720.
The conjugation window in an Escherichia coli K-12 strain with an IncFII plasmid-(Peer Reviewed Journal) Headd, B.J., Bradford, S.A. 2020. The conjugation window in an Escherichia coli K-12 strain with an IncFII plasmid. Applied and Environmental Microbiology. 86(17). Article e00948-20. https://doi.org/10.1128/AEM.00948-20.
Groundwater recharge from drywells under constant head conditions-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Šimunek, J., Kraemer, S. 2020. Groundwater recharge from drywells under constant head conditions. Journal of Hydrology. 583. https://doi.org/10.1016/j.jhydrol.2020.124569.
Modeling virus transport and removal during storage and recovery in heterogeneous aquifers-(Peer Reviewed Journal) Torkzaban, S., Hocking, M., Bradford, S.A., Tazehkand, S.S., Sasidharan, S., Šimunek, J. 2019. Modeling virus transport and removal during storage and recovery in heterogeneous aquifers. Journal of Hydrology. 578. https://doi.org/10.1016/j.jhydrol.2019.124082.
Interaction energies for hollow and solid cylinders: Role of aspect ratio and particle orientation-(Peer Reviewed Journal) Gomez-Flores, A., Bradford, S.A., Wu, L., Kim, H. 2019. Interaction energies for hollow and solid cylinders: Role of aspect ratio and particle orientation. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 580. https://doi.org/10.1016/j.colsurfa.2019.123781.
Mechanisms of graphene oxide aggregation, retention, and release in quartz sand-(Peer Reviewed Journal) Liang, Y., Bradford, S.A., Simunek, J., Klumpp, E. 2018. Mechanisms of graphene oxide aggregation, retention, and release in quartz sand. Science of the Total Environment. 656:70-79. https://doi.org/10.1016/j.scitotenv.2018.11.258.
DLVO Interaction energies for hollow particles: The filling matters-(Peer Reviewed Journal) Shen, C., Bradford, S.A., Flury, M., Huang, Y., Wang, Z., Li, B. 2018. DLVO Interaction energies for hollow particles: The filling matters. Langmuir. 34(43):12764-12775. https://doi.org/10.1021/acs.langmuir.8b02547.
Application of depletion attraction in mineral flotation: I. Theory-(Peer Reviewed Journal) Choi, J., Kim, G., Choi, S., Kim, K., Han, Y., Bradford, S.A., Choi, S.Q., Kim, H. 2018. Application of depletion attraction in mineral flotation: I. Theory. Minerals. 8(10):451. https://doi.org/10.3390/min8100451.
Analysis of stability behavior of carbon black nanoparticles in ecotoxicological media: Hydrophobic and steric effects-(Peer Reviewed Journal) Hwang, G., Gomez-Florez, A., Bradford, S.A., Choi, S., Jo, E., Kim, S.B., Tong, M., Kim, H. 2018. Analysis of stability behavior of carbon black nanoparticles in ecotoxicological media: Hydrophobic and steric effects. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 554:306-316. https://doi.org/10.1016/j.colsurfa.2018.06.049.
Comparison of types and amounts of nanoscale heterogeneity on bacteria retention
-(Peer Reviewed Journal) Bradford, S.A., Sasidharan, S., Kim, H., Hwang, G. 2018. Comparison of types and amounts of nanoscale heterogeneity on bacteria retention. Frontiers in Environmental Science. 6:56. https://doi.org/10.3389/fenvs.2018.00056.
Evaluating drywells for stormwater management and enhanced aquifer recharge-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Simunek, J., Dejong, B., Kraemer, S. 2018. Evaluating drywells for stormwater management and enhanced aquifer recharge. Advances in Water Resources. 1116:167-177. https://doi.org/10.1016/j.advwatres.2018.04.003.
Transport and fate of viruses in sediment and stormwater from a managed aquifer recharge site-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Simunek, J., Torkzaban, S., Vanderzalm, J. 2017. Transport and fate of viruses in sediment and stormwater from a managed aquifer recharge site. Journal of Hydrology. 555:724-735. https://doi.org/10.1016/j.jhydrol.2017.10.062.
DLVO interaction energies between hollow spherical particles and collector surfaces-(Peer Reviewed Journal) Shen, C., Bradford, S.A., Wang, Z., Huang, Y., Zhang, Y., Li, B. 2017. DLVO interaction energies between hollow spherical particles and collector surfaces. Langmuir. 33:10455-10467. http://pubs.acs.org/doi/abs/10.1021/acs.langmuir.7b02383.
Analysis of the effects of natural organic matter in zinc beneficiation-(Peer Reviewed Journal) Silva, R.A., Borja, D., Hwang, G., Hong, G., Gupta, V., Bradford, S.A., Zhang, Y., Kim, H. 2017. Analysis of the effects of natural organic matter in zinc beneficiation. Journal of Cleaner Production. 168:814-822. https://doi.org/10.1016/j.jclepro.2017.09.011.
Transport and retention of bacteria and viruses in biochar-amended sand-(Peer Reviewed Journal) Sasidharan, S., Torkzaban, S., Bradford, S.A., Kookana, R., Page, D., Cook, P. 2016. Transport and retention of bacteria and viruses in biochar-amended sand. Science of the Total Environment. 548:100-109.
Modeling the release of E. coli D21g with transients in water content-(Peer Reviewed Journal) Bradford, S.A., Wang, Y., Torkzaban, S., Simunek, J. 2015. Modeling the release of E. coli D21g with transients in water content. Water Resources Research. 51:3303-3316. doi: 10.1002/2014WR016566.
Release of E.coli D21g with transients in water content-(Peer Reviewed Journal) Wang, Y., Bradford, S.A., Simunek, J. 2014. Release of E.coli D21g with transients in water content. Journal of Environmental Science and Technology. 48:9349-9357.
Transport and fate of microbial pathogens in agricultural settings-(Peer Reviewed Journal) Bradford, S.A., Morales, V.L., Zhang, W., Harvey, R.W., Packman, A.I., Mohanram, A., Welty, C. 2013. Transport and fate of microbial pathogens in agricultural settings. Critical Reviews in Environmental Science Technology. 43(8):775-893.
Modeling microorganism transport and survival in the subsurface-(Peer Reviewed Journal) Bradford, S.A., Wang, Y., Kim, H., Torkzaban, S., Simunek, J. 2014. Modeling microorganism transport and survival in the subsurface. Journal of Environmental Quality. 43(2):421-440.
Numerical modeling of contaminant transport using HYDRUS and its specialized modules-(Peer Reviewed Journal) Simunek, J., Jacques, D., Langergraber, G., Bradford, S.A., Sejna, M., Van Genuchten, M.T. 2013. Numerical modeling of contaminant transport using HYDRUS and its specialized modules. Journal of Indian Institute of Sciences. 93(2):265-284.
Colloid transport in dual-permeability media-(Peer Reviewed Journal) Leij, F.J., Bradford, S.A. 2013. Colloid transport in dual-permeability media. Journal of Contaminant Hydrology. 150:65-76.
Recommendations for nutrient management plans in a semi-Arid environment-(Peer Reviewed Journal) Segal, E., Shouse, P.J., Poss, J.A., Crohn, D.M., Bradford, S.A. 2010. Recommendations for nutrient management plans in a semi-Arid environment. Agriculture, Ecosystems and Environment. 137(2):317-328.
Transport and Straining of E. coli O157:H7 in Saturated Porous Media-(Abstract Only) Bradford, S.A., Simunek, J., Walker, S.L. 2006. Transport and Straining of E. coli O157:H7 in Saturated Porous Media. American Society of Agronomy Meetings in Indianapolis, IN Nov 12-16, 2006. Paper No. 277-5
Transport of Latex Particles in Variably Saturated Heterogeneous Media-(Abstract Only) Han, J., Bradford, S.A., Jin, Y. 2006. Transport of Latex Particles in Variably Saturated Heterogeneous Media. American Society of Agronomy Meetings in Indianapolis, IN Nov 12-16, 2006. Paper No. 182-16
SIGNIFICANCE OF STRAINING IN COLLOID DEPOSITION: EVIDENCE AND IMPLICATIONS-(Peer Reviewed Journal) Bradford, S.A., Simunek, J., Bettahar, M., Van Genuchten, M.T., Yates, S.R. 2006. Significance of straining in colloid deposition: evidence and implications. Water Resources Research. VOL 42, W12S15
TRANSPORT AND FATE OF MANURE-BORNE PATHOGENS: MODELING PERSPECTIVE-(Peer Reviewed Journal) Pachepsky, Y.A., Sadeghi, A.M., Bradford, S.A., Shelton, D.R., Guber, A.K., Dao, T.H. 2006. Transport and fate of manure-borne pathogens: modeling perspective. Agricultural Water Management. Online-(doi:10.1016/j.agwat.2006.06.0l0.)
SIGNIFICANCE OF STRAINING IN COLLOID DEPOSITION: EVIDENCE AND IMPLICATIONS-(Abstract Only) Bradford, S.A., Simunek, J., Bettahar, M., Van Genuchten, M.T., Yates, S.R. 2005. Significance of straining in colloid deposition: evidence and implications. Geological Society of America Meeting. Paper No. 243-4
NEW FEATURES OF HYDRUS-1D, VERSION 3.0-(Proceedings) Simunek, J., Van Genuchten, M.T., Bradford, S.A., Lenhard, R.J. 2005. New Features of HYDRUS-1D, Version 3.0. In: S. Torkzaban and S. Majid Hassanizadeh (eds.), Proceedings of Workshop on HYDRUS Applications, p. 86-89, October 19, 2005, ISBN 90-39341125, Department of Earth Sciences, Utrecht University, Utrecht, The Netherlands.
MODELING OF COLLOID TRANSPORT AND DEPOSITION IN POROUS MEDIA-(Proceedings) Bradford, S.A., Van Genuchten, M.T., Simunek, J. 2005. Modeling of colloid transport and deposition in porous media. Proceedings of the workshop on HYDRUS Applications, Oct. 19, 2005, Utrecht Univ., The Netherlands. p. 1-5.
STRAINING OF COLLOIDS AT TEXTURAL INTERFACES-(Peer Reviewed Journal) Bradford, S.A., Simunek, J., Bettahar, M., Tadassa, Y.F., Van Genuchten, M.T., Yates, S.R. 2005. Straining of colloids at textural interfaces. Water Resources Research. 41:W10404, doi:10.1029/2004WR003675.
STRAINING OF COLLOIDS AT TEXTURAL INTERFACES-(Abstract Only) Bradford, S.A., Simunek, J., Van Genuchten, M.T., Bettahar, M. 2004. Straining of colloids at textural interfaces. ASA-CSSA-SSSA Annual Meeting Abstracts. CD-ROM, Seattle, WA.
MODELING FATE AND TRANSPORT OF MANURE-BORNE PATHOGENS IN THE ENVIRONMENT-(Proceedings) Pachepsky, Y.A., Bradford, S.A., Sadeghi, A.M., Guber, A.K., Shelton, D.R. 2004. Modeling fate and transport of manure-borne pathogens in the environment. In: Proceedings of the Pathogens in the Environment Workshop, February 23-25, 2004, Kansas City, Missouri. p. 34-38.
MODELING COLLOID ATTACHMENT, STRAINING, AND EXCLUSION IN SATURATED POROUS MEDIA-(Peer Reviewed Journal) BRADFORD, S.A., SIMUNEK, J., BETTAHAR, M., VAN GENUCHTEN, M.T., YATES, S.R. MODELING COLLOID ATTACHMENT, STRAINING, AND EXCLUSION IN SATURATED POROUS MEDIA. JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY. 2003. v. 37. p. 2242-2250.