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ARS Home Pacific West Area Davis, California Sustainable Agricultural Water Systems Research People







Scott Alan Bradford    Research Leader Scott A Bradford

Dr. Scott Alan BradfordSoil Scientist
Sustainable Agricultural Water Systems UnitUSDA, ARS, SAWS Unit239 Hopkins RoadDavis, CA 95616
Phone: 1 (530) 400-9357Scott.Bradford@usda.govResearch Interests: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 plansAcademic Degrees:Ph.D.
Soil Science (Soil Physics), University of California, Riverside, 1995Dissertation: Experimental and Theoretical Investigations of Multiphase CapillarityM.S.
Soil Science (Soil Physics), University of California, Riverside, 1991Thesis: Transient State Modeling of Various Irrigation Management StrategiesB.S.
Physics, Brigham Young University, 1989Minors in Chemistry and MathematicsCertified:Passed the 8 hour NCEES Professional Civil Engineering ExamPresent and Past Positions:2000-Present
Soil Scientist (GS-15)
USDA-ARS U.S. Salinity LaboratoryRiverside, CA1999
Adjunct Assistant Professor
Dept. of Civil and Environmental Engineering,University of Michigan, Ann Arbor, MI1995-2000
Postdoctoral Positions (Assistant Research Scientist, Research Investigator, and Research Fellow)
Dept. of Civil and Environmental Engineering,University of Michigan, Ann Arbor, MIProfessional 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 AmericaProfessional 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).Publications(Clicking on the reprint iconReprint Icon  will take you to the publication reprint.)A conditioned Latin hypercube sampling design methodology for ground-truthing transient EM resistivity models-(Peer Reviewed Journal) Osterman, G.K., Lesch, S., Bradford, S.A. 2024. A conditioned Latin hypercube sampling design methodology for ground-truthing transient EM resistivity models. Computers and Geosciences. https://doi.org/10.1016/j.cageo.2024.105582.Coupling water, solute, and sediment transport into a new computationally efficient hydrologic model-(Peer Reviewed Journal) Chen, L., Šimunek, J., Bradford, S.A., Ajami, H., Meles, M.B. 2023. Coupling water, solute, and sediment transport into a new computationally efficient hydrologic model. Journal of Hydrology. 628. Article 130495. https://doi.org/10.1016/j.jhydrol.2023.130495.Retention and release of black phosphorus nanoparticles in porous media under various physicochemical conditions-(Peer Reviewed Journal) Liang, Y., Liu, J., Dong, P., Qin, Y., Zhang, R., Bradford, S.A. 2023. Retention and release of black phosphorus nanoparticles in porous media under various physicochemical conditions. Chemosphere. 339. Article 139604. https://doi.org/10.1016/j.chemosphere.2023.139604.Divalent cation contributions to the co-transport and deposition of functionalized multi-walled carbon nanotubes and soil nanoparticles in porous media in the presence of bentonite or geothite nanoparticles: Experiment and-(Peer Reviewed Journal) Zhang, M., Bradford, S.A., Klumpp, E., Šimunek, J., Mo, Y., Ding, K., Wan, Q., Wang, S., Jin, C., Qiu, R. 2023. Divalent cation contributions to the co-transport and deposition of functionalized multi-walled carbon nanotubes and soil nanoparticles in porous media in the presence of bentonite or geothite nanoparticles: Experiment and. Journal of Hydrology. 625(Part A). Article 129909. https://doi.org/10.1016/j.jhydrol.2023.129909.Statistical analysis, machine learning modeling, and text analytics of aggregation attachment efficiency: Mono and binary particle systems-(Peer Reviewed Journal) Gomez-Flores, A., Bradford, S.A., Hong, G., Kim, H. 2023. Statistical analysis, machine learning modeling, and text analytics of aggregation attachment efficiency: Mono and binary particle systems. Journal of Hazardous Materials. 454. Article 131482. https://doi.org/10.1016/j.jhazmat.2023.131482.Prediction of attachment efficiency using machine learning on a comprehensive database and its validation-(Peer Reviewed Journal) Gomez-Flores, A., Bradford, S.A., Cai, L., Urík, M., Kim, H. 2022. Prediction of attachment efficiency using machine learning on a comprehensive database and its validation. Water Research. 229. Article 119429. https://doi.org/10.1016/j.watres.2022.119429.Aging of colloidal contaminants and pathogens in the soil environment: Implications for nanoplastic and COVID-19 risk mitigation-(Peer Reviewed Journal) Wang, L., Hu, Z., Yin, H., Bradford, S.A., Luo, J., Hou, D. 2022. Aging of colloidal contaminants and pathogens in the soil environment: Implications for nanoplastic and COVID-19 risk mitigation. Soil Use and Management. 39(1):70-91. https://doi.org/10.1111/sum.12849.A computationally efficient hydrologic modeling framework to simulate surface-subsurface hydrological processes at the hillslope scale-(Peer Reviewed Journal) Chen, L., Simunek, J., Bradford, S.A., Ajami, H., Meles, M.B. 2022. A computationally efficient hydrologic modeling framework to simulate surface-subsurface hydrological processes at the hillslope scale. Journal of Hydrology. 614. Article 128539. https://doi.org/10.1016/j.jhydrol.2022.128539.Prediction of colloid sticking efficiency at pore-scale and macroscale using a pore network model-(Peer Reviewed Journal) Lin, D., Zhang, X., Hu, L., Bradford, S.A., Shen, C. 2022. Prediction of colloid sticking efficiency at pore-scale and macroscale using a pore network model. Journal of Hydrology. 612(C). Article 128253. https://doi.org/10.1016/j.jhydrol.2022.128253.Significance of non-DLVO interactions on the co-transport of
functionalized multiwalled carbon nanotubes and soil nanoparticles in porous media-(Peer Reviewed Journal) Zhang, M., Bradford, S.A., Klumpp, E., Šimunek, J., Wang, S., Wan, Q., Jin, C., Qiu, R. 2022. Significance of non-DLVO interactions on the co-transport of functionalized multiwalled carbon nanotubes and soil nanoparticles in porous media. Environmental Science and Technology. https://doi.org/10.1021/acs.est.2c00681.Micro- and nanoplastics retention in porous media exhibits different dependence on grain surface roughness and clay coating with particle size-(Peer Reviewed Journal) Liang, Y., Luo, Y., Shen, C., Bradford, S.A. 2022. Micro- and nanoplastics retention in porous media exhibits different dependence on grain surface roughness and clay coating with particle size. Water Research. 221. Article 118717. https://doi.org/10.1016/j.watres.2022.118717.Biogeochemical cycle of mercury and controlling technologies: Publications in critical reviews in environmental science & technology during 2017–2021-(Review Article) Wang, J., Ma, L.Q., Letcher, R.J., Bradford, S.A., Feng, X., Rinklebe, J. 2022. Biogeochemical cycle of mercury and controlling technologies: Publications in critical reviews in environmental science & technology during 2017–2021. Critical Reviews in Environmental Science Technology. 52(24): 4325-4330. https://doi.org/10.1080/10643389.2022.2071210.Prediction of collector contact efficiency for colloid transport in porous media using Pore-Network and Neural-Network models-(Peer Reviewed Journal) Lin, D., Hu, L., Bradford, S.A., Zhang, X., Lo, I.M. 2022. Prediction of collector contact efficiency for colloid transport in porous media using Pore-Network and Neural-Network models. Separation and Purification Technology. 290. Article 120846. https://doi.org/10.1016/j.seppur.2022.120846.Environmental applications and risks of nanomaterials: An introduction to CREST publications during 2018–2021-(Review Article) Bradford, S.A., Shen, C., Kim, H., Letcher, R.J., Rinklebe, J., Ok, Y., Ma, L. 2021. Environmental applications and risks of nanomaterials: An introduction to CREST publications during 2018–2021. Critical Reviews in Environmental Science Technology. https://doi.org/10.1080/10643389.2021.2020425.Novel analytical expressions for determining van der Waals interaction between a particle and air-water interface: Unexpected stronger van der Waals force than capillary force-(Peer Reviewed Journal) Du, Y., Bradford, S.A., Shen, C., Li, T., Bi, X., Liu, D., Huang, Y. 2021. Novel analytical expressions for determining van der Waals interaction between a particle and air-water interface: Unexpected stronger van der Waals force than capillary force. Journal of Colloid and Interface Science. 610:982-993. https://doi.org/10.1016/j.jcis.2021.11.157.Pore-network modeling of colloid transport and retention considering surface deposition, hydrodynamic bridging, and straining-(Peer Reviewed Journal) Lin, D., Hu, L., Bradford, S.A., Zhang, X., Lo, I.M. 2021. Pore-network modeling of colloid transport and retention considering surface deposition, hydrodynamic bridging, and straining. Journal of Hydrology. 603 Part B. Article 127020. https://doi.org/10.1016/j.jhydrol.2021.127020.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.Evidence on enhanced transport and release of silver nanoparticles by colloids in soil due to modification of grain surface morphology and co-transport-(Peer Reviewed Journal) Liang, Y., Luo, Y., Lu, Z., Klumpp, E., Shen, C., Bradford, S.A. 2021. Evidence on enhanced transport and release of silver nanoparticles by colloids in soil due to modification of grain surface morphology and co-transport. Environmental Pollution. 276. Article 116661. https://doi.org/10.1016/j.envpol.2021.116661.Colloid interaction energies for surfaces with steric effects and incompressible and/or compressible roughness-(Peer Reviewed Journal) Bradford, S.A., Sasidharan, S., Kim, H., Gomez-Flores, A., Li, T., Shen, C. 2021. Colloid interaction energies for surfaces with steric effects and incompressible and/or compressible roughness. Langmuir. 37(4):1501-1510. https://doi.org/10.1021/acs.langmuir.0c03029.Simulation of colloid transport and retention using a pore-network model with roughness and chemical heterogeneity on pore surfaces-(Peer Reviewed Journal) Lin, D., Hu, L., Bradford, S.A., Zhang, X., Lo, I.M. 2021. Simulation of colloid transport and retention using a pore-network model with roughness and chemical heterogeneity on pore surfaces. Water Resources Research. 57(2). Article e2020WR028571. https://doi.org/10.1029/2020WR028571.Non-monotonic contribution of nonionic surfactant on the retention of functionalized multi-walled carbon nanotubes in porous media-(Peer Reviewed Journal) Zhang, M., Bradford, S.A., Klumpp, E., Šimunek, J., Jin, C., Qiu, R. 2020. Non-monotonic contribution of nonionic surfactant on the retention of functionalized multi-walled carbon nanotubes in porous media. Journal of Hazardous Materials. 407. Article 124874. https://doi.org/10.1016/j.jhazmat.2020.124874.Impact of phosphate adsorption on the mobility of PANI-supported nano zero-valent iron-(Peer Reviewed Journal) Lin, D., Bradford, S.A., Hu, L., Lo, I. 2021. Impact of phosphate adsorption on the mobility of PANI-supported nano zero-valent iron. Vadose Zone Journal. 20(2). Article e20091. https://doi.org/10.1002/vzj2.20091.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.Synergies of surface roughness and hydration on colloid detachment in saturated porous media: Column and atomic force microscopy studies-(Peer Reviewed Journal) Li, T., Shen, C., Wu, S., Jin, C., Bradford, S.A. 2020. Synergies of surface roughness and hydration on colloid detachment in saturated porous media: Column and atomic force microscopy studies. Water Research. 183. https://doi.org/10.1016/j.watres.2020.116068.Particle-bubble interaction energies for particles with physical and chemical heterogeneities-(Peer Reviewed Journal) Gomez-Flores, A., Bradford, S.A., Hwang, G., Heyes, G.W., Kim, H. 2020. Particle-bubble interaction energies for particles with physical and chemical heterogeneities. Minerals Engineering. 155. https://doi.org/10.1016/j.mineng.2020.106472.Shape and orientation of bare silica particles influence their deposition under intermediate ionic strength: A study with QCM–D and DLVO theory-(Peer Reviewed Journal) Gomez-Flores, A., Bradford, S.A., Hwang, G., Choi, S., Tong, M., Kim, H. 2020. Shape and orientation of bare silica particles influence their deposition under intermediate ionic strength: A study with QCM–D and DLVO theory. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 599. https://doi.org/10.1016/j.colsurfa.2020.124921.Release of colloidal biochar during transient chemical conditions: The humic acid effect-(Peer Reviewed Journal) Wang, Y., Bradford, S.A., Shang, J. 2020. Release of colloidal biochar during transient chemical conditions: The humic acid effect. Environmental Pollution. 260. https://doi.org/10.1016/j.envpol.2020.114068.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.Evidence for the critical role of nanoscale surface roughness on the retention and release of silver nanoparticles in porous media-(Peer Reviewed Journal) Liang, Y., Zhou, J., Dong, Y., Klumpp, E., Simunek, J., Bradford, S.A. 2020. Evidence for the critical role of nanoscale surface roughness on the retention and release of silver nanoparticles in porous media. Environmental Pollution. 258. https://doi.org/10.1016/j.envpol.2019.113803.Transport and retention of engineered silver nanoparticles in carbonate-rich sediments in the presence and absence of soil organic matter-(Peer Reviewed Journal) Adrian, Y.F., Schneidewind, U., Bradford, S.A., Simunek, J., Klumpp, E., Azzam, R. 2019. Transport and retention of engineered silver nanoparticles in carbonate-rich sediments in the presence and absence of soil organic matter. Environmental Pollution. 255. https://doi.org/10.1016/j.envpol.2019.113124.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.Nano-bubble retention in saturated porous media under repulsive van der waals and electrostatic conditions-(Peer Reviewed Journal) Hamamoto, S., Sugimoto, T., Takemura, T., Nishimura, T., Bradford, S.A. 2019. Nano-bubble retention in saturated porous media under repulsive van der waals and electrostatic conditions. Langmuir. 35(21):6853-6860. https://doi.org/10.1021/acs.langmuir.9b00507.Co-transport of multi-walled carbon nanotubes and
sodium dodecylbenzenesulfonate in chemically heterogeneous porous media-(Peer Reviewed Journal) Zhang, M., Bradford, S.A., Simunek, J., Vereecken, H., Klumpp, E. 2019. Co-transport of multi-walled carbon nanotubes and sodium dodecylbenzenesulfonate in chemically heterogeneous porous media. Environmental Pollution. 247:907-916. https://doi.org/10.1016/j.envpol.2019.01.106.Physics-informed data-driven models to predict surface runoff water quantity and quality in agricultural fields-(Peer Reviewed Journal) Liang, J., Li, W., Bradford, S.A., Simunek, J. 2019. Physics-informed data-driven models to predict surface runoff water quantity and quality in agricultural fields. Water. 11(2):200. https://doi.org/10.3390/w11020200.Drywell infiltration and hydraulic properties in heterogeneous soil profiles-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Simunek, J., Kraemer, S.R. 2019. Drywell infiltration and hydraulic properties in heterogeneous soil profiles. Journal of Hydrology. 570:598-611. https://doi.org/10.1016/j.jhydrol.2018.12.073.Transport of biochar colloids in saturated porous media in the presence of humic substances or proteins-(Peer Reviewed Journal) Yang, W., Bradford, S.A., Yang, W., Sharma, P., Shang, J., Li, B. 2018. Transport of biochar colloids in saturated porous media in the presence of humic substances or proteins. Environmental Pollution. 246:855-863. https://doi.org/10.1016/j.envpol.2018.12.075.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.Application of depletion attraction in mineral flotation: II. Effects of depletant concentration-(Peer Reviewed Journal) Kim, G., Choi, J., Choi, S., Kim, K., Han, Y., Bradford, S.A., Choi, S.Q., Kim, H. 2018. Application of depletion attraction in mineral flotation: II. Effects of depletant concentration. Minerals. 8(10):450. https://doi.org/10.3390/min8100450.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.Physicochemical factors that favor conjugation of an antibiotic resistant plasmid in non-growing bacterial cultures in the absence and presence of antibiotics-(Peer Reviewed Journal) Headd, B.J., Bradford, S.A. 2018. Physicochemical factors that favor conjugation of an antibiotic resistant plasmid in non-growing bacterial cultures in the absence and presence of antibiotics. Frontiers in Microbiology. 9:2122. https://doi.org/10.3389/fmicb.2018.02122.Modeling the transport and retention of polydispersed colloidal suspensions in porous media-(Peer Reviewed Journal) Bradford, S.A., Leij, F.J. 2018. Modeling the transport and retention of polydispersed colloidal suspensions in porous media. Chemical Engineering Science. 192:972-980. https://doi.org/10.1016/j.ces.2018.08.037.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.Can nanoscale surface charge heterogeneity really explain colloid detachment from primary minima upon reduction of solution ionic strength?-(Peer Reviewed Journal) Shen, C., Bradford, S.A., Li, T., Li, B., Huang, Y. 2018. Can nanoscale surface charge heterogeneity really explain colloid detachment from primary minima upon reduction of solution ionic strength? Journal of Nanoparticle Research. 20:165. https://doi.org/10.1007/s11051-018-4265-8.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.Minimizing virus transport in porous media by optimizing solid phase inactivation-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Simunek, J., Torkzaban, S. 2018. Minimizing virus transport in porous media by optimizing solid phase inactivation. Journal of Environmental Quality. doi:10.2134/jeq2018.01.0027.Transport and retention of surfactant- and polymer-stabilized engineered silver nanoparticles in silicate-dominated aquifer material-(Peer Reviewed Journal) Adrian, Y.F., Schneidewind, U., Bradford, S.A., Simunek, J., Fernandez-Steeger, T.M., Azzam, R. 2018. Transport and retention of surfactant- and polymer-stabilized engineered silver nanoparticles in silicate-dominated aquifer material. Environmental Pollution. 236:195-207. https://doi.org/10.1016/j.envpol.2018.01.011.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.Contributions of nanoscale roughness to anomalous colloid retention and stability behavior-(Abstract Only)Evaluating drywells for stormwater management and enhanced aquifer recharge-(Abstract Only)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.Contributions of nanoscale roughness to anomalous colloid retention and stability behavior-(Peer Reviewed Journal) Bradford, S.A., Kim, H., Shen, C., Sasidharan, S., Shang, J. 2017. Contributions of nanoscale roughness to anomalous colloid retention and stability behavior. Langmuir. 33:10094-10105. http://pubs.acs.org/doi/abs/10.1021/acs.langmuir.7b02445.Unraveling complexities of velocity dependent retention and release parameters for E. coli in saturated porous media-(Peer Reviewed Journal) Sasidharan, S., Bradford, S.A., Torkzaban, S., Ye, X., Vanderzalm, J., Du, X., Page, D. 2017. Unraveling complexities of velocity dependent retention and release parameters for E. coli in saturated porous media. Science of the Total Environment. 603:406-415. doi: 10.1016/j.scitotenv.2017.06.091.Adapting HYDRUS-1D to simulate overland flow and reactive transport during sheet flow deviations-(Peer Reviewed Journal) Liang, J., Bradford, S.A., Simunek, J., Hartmann, A. 2017. Adapting HYDRUS-1D to simulate overland flow and reactive transport during sheet flow deviations. Vadose Zone Journal. 16(6):1-18. doi: 10.2136/vzj2016.11.0113.Critical role of preferential flow in field-scale pathogen transport and retention-(Peer Reviewed Journal) Bradford, S.A., Feike, L.J., Schijven, J., Torkzaban, S. 2017. Critical role of preferential flow in field-scale pathogen transport and retention. Vadose Zone Journal. 16(4):1-13. doi: 10.2136/vzj2016.12.0127.H51E-1535: Biogeochemical factors influencing the transport and fate of colloids and colloid-associated contaminants in the vadose zone-(Abstract Only)Co-transport of chlordecone and sulfadiazine in the presence of functionalized multi-walled carbon nanotubes in soils-(Peer Reviewed Journal) Zhang, M., Engelhardt, I., Simunek, J., Bradford, S.A., Kasel, D., Berns, A.E., Vereecken, H., Klumpp, E. 2016. Co-transport of chlordecone and sulfadiazine in the presence of functionalized multi-walled carbon nanotubes in soils. Environmental Pollution. 221:470-479. doi: 10.1016/j.envpol.2016.12.018.Roles of cation valance and exchange on the retention and colloid-facilitated transport of functionalized multi-walled carbon nanotubes in a natural soil-(Peer Reviewed Journal) Zhang, M., Bradford, S.A., Simunek, J., Vereeken, H., Klumpp, E. 2016. Roles of cation valance and exchange on the retention and colloid-facilitated transport of functionalized multi-walled carbon nanotubes in a natural soil. Water Research. 109:358-366. doi: 10.1016/j.watres.2016.11.0062.Temperature dependency of virus and nanoparticle transport and retention in saturated porous media-(Peer Reviewed Journal) Sasidharan, S., Torkzaban, S., Bradford, S.A., Cook, P., Vadakattu, G.V. 2016. Temperature dependency of virus and nanoparticle transport and retention in saturated porous media. Journal of Contaminant Hydrology. 196:10-20. doi: 10.1016/j.jconhyd.2016.11.004.Future research needs involving pathogens in groundwater-(Peer Reviewed Journal) Bradford, S.A., Harvey, R.W. 2016. Future research needs involving pathogens in groundwater. Hydrogeology Journal. 24(4):1-8. doi: 10.1007/s.10040-016-1501-0.Analytic solutions for colloid transport with time- or depth-dependent retention in porous media-(Peer Reviewed Journal) Leij, F.J., Bradford, S.A., Sciortino, A. 2016. Analytic solutions for colloid transport with time- or depth-dependent retention in porous media. Journal of Contaminant Hydrology. 195:40-51. doi: 10.1016/j.jconhyd.2016.10.006.Do goethite surfaces really control the transport and retention of multi-walled carbon nanotubes in chemically heterogeneous porous media?-(Peer Reviewed Journal) Zhang, M., Bradford, S.A., Simunek, J., Vereecken, H., Klumpp, E. 2016. Do goethite surfaces really control the transport and retention of multi-walled carbon nanotubes in chemically heterogeneous porous media? Journal of Environmental Science and Technology. 50:12713-12721. doi: 10.1021/aces.est.6b03285.Evaluating the transport of bacillus subtilis spores as a potential surrogate for Cryptosporidium parvum Oocysts-(Peer Reviewed Journal) Bradford, S.A., Kim, H., Headd, B.J., Torkzaban, S. 2015. Evaluating the transport of bacillus subtilis spores as a potential surrogate for Cryptosporidium parvum Oocysts . Environmental Science and Technology. 50:1295-1303. doi: 10.1021/acs.est.5b05296.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.Use of aerobic spores as a surrogate for cryptosporidium oocysts in drinking water and supplies-(Review Article) Headd, B.J., Bradford, S.A. 2015. Use of aerobic spores as a surrogate for cryptosporidium oocysts in drinking water and supplies. Water Research. 90:185-202. doi: 10.1016/j.watres.2015.12.024.Transport, retention, and long-term release behavior of ZnO nanoparticle aggregates in saturated quartz sand: Role of solution pH and biofilm coating-(Peer Reviewed Journal) Han, Y., Hwang, G., Kim, D., Bradford, S.A., Lee, B., Eom, I., Je Kim, P., Choi, S.Q., Kim, H. 2015. Transport, retention, and long-term release behavior of ZnO nanoparticle aggregates in saturated quartz sand: Role of solution pH and biofilm coating. Water Research. 90:247-257. doi: 10.1016/j.watres.2015.12.009.Determining parameters and mechanisms of colloid retention and release in porous media-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S. 2015. Determining parameters and mechanisms of colloid retention and release in porous media. Langmuir. doi: 10.1021/acs.langmuir.5b03080.Critical role of surface roughness on colloid retention and release in porous media-(Peer Reviewed Journal) Torkzaban, S., Bradford, S.A. 2015. Critical role of surface roughness on colloid retention and release in porous media. Water Research. 88:274-284. doi: 10.1016/j.watres.2015.10.022.Microbial transport and fate in the subsurface: An introduction to the special collection-(Review Article) Bradford, S.A., Schijven, J., Harter, T. 2015. Microbial transport and fate in the subsurface: An introduction to the special collection. Journal of Environmental Quality. doi: 10.2134/jeq2015.07.0375.Colloid release and clogging in porous media: Effects of solution ionic strength and flow velocity-(Peer Reviewed Journal) Torkzaban, S., Bradford, S.A., Vanderzalm, J., Patterson, B.M., Harris, B., Prommer, H. 2015. Colloid release and clogging in porous media: Effects of solution ionic strength and flow velocity. Journal of Contaminant Hydrology. 181: 161-171.doi: 10.1016/j.jconhyd.2015.06.005.Langmuirian blocking of irreversible colloid retention: analytical solution, moments, and setback distance-(Peer Reviewed Journal) Leij, F.J., Bradford, S.A., Wang, Y., Sciortino, A. 2015. Langmuirian blocking of irreversible colloid retention: analytical solution, moments, and setback distance. Journal of Environmental Quality. 44:1473-1482. doi: 10.2134/jeq2015.03.0147.Transport of E. coli D21g with runoff water under different solution chemistry conditions and surface slopes-(Peer Reviewed Journal) Bradford, S.A., Headd, B.J., Arye, G., Simunek, J. 2015. Transport of E. coli D21g with runoff water under different solution chemistry conditions and surface slopes. Journal of Hydrology. 525:760-768.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.Transport, retention, and size perturbation of graphene oxide in saturated porous media: Effects of input concentration and grain size-(Peer Reviewed Journal) Sun, Y., Gao, B., Bradford, S.A., Wu, L., Chen, H., Shi, X., Wu, J. 2014. Transport, retention, and size perturbation of graphene oxide in saturated porous media: Effects of input concentration and grain size. Water Research. 68:24-33.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.An explanation for differences in the process of colloid adsorption in batch and column studies-(Peer Reviewed Journal) Treumann, S., Torkzaban, S., Bradford, S.A., Visalakshan, R.M., Page, D. 2014. An explanation for differences in the process of colloid adsorption in batch and column studies. Journal of Contaminant Hydrology. 164:219-229.Coupled effects of hydrodynamic and solution chemistry conditions on long-term nanoparticle transport and deposition in saturated porous media-(Peer Reviewed Journal) Sasidharan, S., Torkzaban, S., Bradford, S.A., Dillon, P.J., Cook, P.G. 2014. Coupled effects of hydrodynamic and solution chemistry conditions on long-term nanoparticle transport and deposition in saturated porous media. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 457:169-179.Equilibrium and kinetic models for colloid release under transient solution chemistry conditions-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S., Leij, F., Simunek, J. 2015. Equilibrium and kinetic models for colloid release under transient solution chemistry conditions. Journal of Contaminant Hydrology. 181:141-152.doi: 10.1016/j.jconhyd.2015.04.003.Estimation and upscaling of dual-permeability model parameters for the transport of E.coli D21g in soils with preferential flow-(Peer Reviewed Journal) Wang, Y., Bradford, S.A., Simunek, J. 2014. Estimation and upscaling of dual-permeability model parameters for the transport of E.coli D21g in soils with preferential flow. Journal of Contaminant Hydrology. 159:57-66.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.Retention and remobilization of stabilized silver nanoparticles in an undisturbed loamy sand soil-(Peer Reviewed Journal) Liang, Y., Bradford, S.A., Simunek, J., Heggen, M., Vereecken, H., Klumpp, E. 2013. Retention and remobilization of stabilized silver nanoparticles in an undisturbed loamy sand soil. Journal of Environmental Science and Technology. 47:12229-12237.Physicochemical factors influencing the preferential transport of Escherichia coli in soils-(Peer Reviewed Journal) Wang, Y., Bradford, S.A., Simunek, J. 2014. Physicochemical factors influencing the preferential transport of Escherichia coli in soils. Vadose Zone Journal. DOI: 10.2136/vzj2013.07.0120.Release of quantum dot nanoparticles in porous media: Role of cation exchange and aging time-(Peer Reviewed Journal) Torkzaban, S., Bradford, S.A., Wan, J., Tokunaga, T., Masoudih, A. 2013. Release of quantum dot nanoparticles in porous media: Role of cation exchange and aging time. Journal of Environmental Science and Technology. 47(20):11528-11536.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.A theoretical analysis of colloid attachment and straining in chemically heterogeneous porous media-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S., Shapiro, A. 2013. A theoretical analysis of colloid attachment and straining in chemically heterogeneous porous media. Langmuir. 29:6944-6952.Limited transport of functionalized multi-walled carbon nanotubes in two natural soils-(Peer Reviewed Journal) Kasel, D., Bradford, S.A., Simunek, J., Putz, T., Vereecken, H., Klumpp, E. 2013. Limited transport of functionalized multi-walled carbon nanotubes in two natural soils. Environmental Pollution. 180:152-158.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.Transport and fate of microorganisms in soils with preferential flow under different solution chemistry conditions-(Peer Reviewed Journal) Wang, Y., Bradford, S.A., Simunek, J. 2013. Transport and fate of microorganisms in soils with preferential flow under different solution chemistry conditions. Water Resources Research. doi:10.1002/wrcr.20174.Colloid interaction energies for physically and chemically heterogeneous porous media-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S. 2013. Colloid interaction energies for physically and chemically heterogeneous porous media. Langmuir. 29(11):3668-3676.Exact analytical solutions for contaminant transport in rivers 1. The equilibrium advection-dispersion equation-(Peer Reviewed Journal) Van Genuchten, M.T., Leij, F.J., Skaggs, T.H., Toride, N., Bradford, S.A., Pontedeiro, E.M. 2013. Exact analytical solutions for contaminant transport in rivers 1. The equilibrium advection-dispersion equation. Journal of Hydrology and Hydromechanics. 61(2):146-160.Exact analytical solutions for contaminant transport in rivers 2. Transient storage and decay chain solutions-(Peer Reviewed Journal) Van Genuchten, M.T., Leij, F.J., Skaggs, T.H., Toride, N., Bradford, S.A., Pontedeiro, E.M. 2013. Exact analytical solutions for contaminant transport in rivers 2. Transient storage and decay chain solutions. Journal of Hydrology and Hydromechanics. 61(3):250-259.Sensitivity of the transport and retention of stabilized silver nanoparticles to physicochemical factors-(Peer Reviewed Journal) Liang, Y., Bradford, S.A., Simunek, J., Vereecken, H., Klumpp, E. 2013. Sensitivity of the transport and retention of stabilized silver nanoparticles to physicochemical factors. Water Research. 47(7):2572-2582.Synergistic ammonia losses from animal wastewater-(Peer Reviewed Journal) Lee, S.R., Yates, S.R., Robarge, W.P., Walker, J.T., Bradford, S.A. 2013. Synergistic ammonia losses from animal wastewater. Atmospheric Environment. 17:245-250.Transport and retention of multi-walled carbon nanotubes in saturated porous media: Effects of input concentration and grain size-(Peer Reviewed Journal) Kasel, D., Bradford, S.A., Simunek, J., Heggen, M., Vereecken, H., Klumpp, E. 2013. Transport and retention of multi-walled carbon nanotubes in saturated porous media: Effects of input concentration and grain size. Water Research. 47(2):933-944.Colloid adhesive parameters for chemical heterogeneous porous media-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S. 2012. Colloid adhesive parameters for chemical heterogeneous porous media. Langmuir. 28:13643-13651.Modeling colloid and microorganism transport and release with transients in solution ionic strength-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S., Kim, H., Simunek, J. 2012. Modeling colloid and microorganism transport and release with transients in solution ionic strength. Water Resources Research. doi:10.1029/2012WR012468.Causes and implications of colloid and microorganism retention hysteresis-(Peer Reviewed Journal) Bradford, S.A., Kim, H. 2012. Causes and implications of colloid and microorganism retention hysteresis. Journal of Contaminant Hydrology. 138-139:83-92.Transport of ARS-labeled hydroxyapatite nanoparticles in saturated granular media is influenced by surface charge variability even in the presence of humic acid-(Peer Reviewed Journal) Wang, D., Bradford, S.A., Harvey, R.W., Hao, X., Zhou, D. 2012. Transport of ARS-labeled hydroxyapatite nanoparticles in saturated granular media is influenced by surface charge variability even in the presence of humic acid. Journal of Hazardous Materials. 229-230:179-176.Impacts of bridging complexation on the transport of surface-modified nanoparticles in saturated sand-(Peer Reviewed Journal) Torkzaban, S., Wan, J., Tokunaga, T.K., Bradford, S.A. 2012. Impacts of bridging complexation on the transport of surface-modified nanoparticles in saturated sand. Journal of Contaminant Hydrology. 136-137:86-95.Anaerobic transformation kinetics and mechanism of steroid estrogenic hormones in dairy lagoon water-(Peer Reviewed Journal) Zheng, W., Li, X., Yates, S.R., Bradford, S.A. 2012. Anaerobic transformation kinetics and mechanism of steroid estrogenic hormones in dairy lagoon water. Environmental Science and Technology. 46(10):5471-5478.Humic acid facilitates the transport of ARS-labeled hydroxyapatite nanoparticles in iron oxyhydroxide-coated sand-(Peer Reviewed Journal) Wang, D., Bradford, S.A., Harvey, R.W., Gao, B., Cang, L., Zhou, D. 2012. Humic acid facilitates the transport of ARS-labeled hydroxyapatite Nanoparticles in iron oxyhydroxide-coated sand. Environmental Science and Technology. 46:2738-2745.Facilitated transport of copper with hydroxyapatite nanoparticles in saturated sand-(Peer Reviewed Journal) Wang, D., Bradford, S.A., Paradelo, M., Peijnenburg, W., Zhou, D. 2011. Facilitated transport of copper with hydroxyapatite nanoparticles in saturated sand. Soil Science Society of America Journal. 76(2):375-388.Facilitated transport of Cu with hydroxyapatite nanoparticles in saturated sand:  Effects of solution ionic strength and composition-(Peer Reviewed Journal) Wang, D., Paradelo, M., Bradford, S.A., Peijnenburg, W.J., Chu, L., Zhou, D. 2011. Facilitated transport of Cu with hydroxyapatite nanoparticles in saturated sand:  Effects of solution ionic strength and composition. Water Research. 45:5905-5915.Modeling colloid transport and retention in saturated porous media under unfavorable attachment conditions-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S., Simunek, J. 2011. Modeling colloid transport and retention in saturated porous media under unfavorable attachment conditions. Water Resources Research. 47:W10503. DOI:10.1029/2011WR010812.Pore-scale simulations to determine the applied hydrodynamic torque and colloid immobilization-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S., Wiegmann, A. 2011. Pore-scale simulations to determine the applied hydrodynamic torque and colloid immobilization. Vadose Zone Journal. 10:252-261.Comparison of model- and design-based sampling strategies for characterizing spatial variablity with ECa-directed soil sampling-(Peer Reviewed Journal) Corwin, D.L., Lesch, S.M., Segal, E., Shouse, P.J., Skaggs, T.H., Bradford, S.A. 2010. Comparison of model- and design-based sampling strategies for characterizing spatial variablity with ECa-directed soil sampling. Journal of Environmental & Engineering Geophysics. 15(3):147-162.Implications of cation exchange on clay release and colloid-facilitated transport in porous media-(Peer Reviewed Journal) Bradford, S.A., Kim, H.K. 2010. Implications of cation exchange on clay release and colloid-facilitated transport in porous media. Journal of Environmental Quality. 39(6):2040-2046.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.Hysteresis of Colloid Retention and Release in Saturated Porous Media During Transients in Solution Chemistry-(Peer Reviewed Journal) Torkzaban, S., Kim, H.K., Simunek, J., Bradford, S.A. 2010. Hysteresis of Colloid Retention and Release in Saturated Porous Media During Transients in Solution Chemistry. Journal of Environmental Science and Technology. 44(5):1662-1669.Measuring Particle Size Distribution using Laser Diffraction: Implications for Predicting Soil Hydraulic Properties-(Peer Reviewed Journal) Segal, E., Shouse, P.J., Bradford, S.A., Skaggs, T.H., Corwin, D.L. 2009. Measuring Particle Size Distribution using Laser Diffraction: Implications for Predicting Soil Hydraulic Properties. Soil Science. 174(12)639:645.Coupled Factors Influencing the Transport and Retention of Cryptosporidium Parvum Oocysts in Saturated Porous Media-(Peer Reviewed Journal) Kim, H., Walker, S., Bradford, S.A. 2010. Coupled Factors Influencing the Transport and Retention of Cryptosporidium Parvum Oocysts in Saturated Porous Media. Water Research. 44(4):1213-1223.Combined physical and chemical nonequilibrium transport model: Analytical solution, moments, and application to colloids-(Peer Reviewed Journal) Leij, F.J., Bradford, S.A. 2009. Combined physical and chemical nonequilibrium transport model: Analytical solution, moments, and application to colloids. Journal of Contaminant Hydrology. 110(3-4)87-99.Macromolecule Mediated Transport and Retention of Escherichia coli O157:H7 in Saturated Porous Media-(Peer Reviewed Journal) Kim, H., Walker, S., Bradford, S.A. 2010. Macromolecule Mediated Transport and Retention of Escherichia coli O157:H7 in Saturated Porous Media. Water Research. 44(4):1082-1093.Reply to comment by William P. Johnson et al. on ‘‘Transport and fate of bacteria in porous media: Coupled effects of chemical conditions and pore space geometry’’-(Other) Torkzaban, S., Walker, S.L., Bradford, S.A. 2009. Reply to comment by William P. Johnson et al. on ‘‘Transport and fate of bacteria in porous media: Coupled effects of chemical conditions and pore space geometry’’. Water Resources Research. 45:W09604Coupled Factors Influencing Concentration Dependent Colloid Transport and Retention in Saturated Porous Media-(Peer Reviewed Journal) Bradford, S.A., Kim, H.N., Haznedaroglu, B.Z., Torkzaban, S., Walker, S.L. 2009. Coupled Factors Influencing Concentration Dependent Colloid Transport and Retention in Saturated Porous Media. Environmental Science and Technology. 43(18)6996-7002.Surface Characteristics and Adhesion Behavior of Escherichia coli O157:H7: Role of Extracellular Macromolecules-(Peer Reviewed Journal) Kim, H.N., Hong, Y., Lee, I., Bradford, S.A., Walker, S.L. 2009. Surface Characteristics and Adhesion Behavior of Escherichia coli O157:H7: Role of Extracellular Macromolecules. Biomacromolecules. 10(9):2556-2564.Escherichia coli O157:H7 Transport in Saturated Porous Media: Role of Solution Chemistry and Surface Macromolecules-(Peer Reviewed Journal) Kim, H., Bradford, S.A., Walker, S. 2009. Escherichia coli O157:H7 Transport in Saturated Porous Media: Role of Solution Chemistry and Surface Macromolecules. Journal of Environmental Science & Technology, 43(12):4340-4347.Relative Transport Behavior of Escherichia coli O157:H7 and Salmonella enterica serovar Pullorum in Packed Bed Column Systems: Influence of Solution Chemistry and Cell Concentration-(Peer Reviewed Journal) Haznedaroglu, B.Z., Kim, H.N., Bradford, S.A., Walker, S.L. 2009. Relative Transport Behavior of Escherichia coli O157:H7 and Salmonella enterica serovar Pullorum in Packed Bed Column Systems: Influence of Solution Chemistry and Cell Concentration. Environmental Science and Technology. 43(6):1838-1844.Deterministic Analysis and Upscaling of Bromide Transport in a Heterogeneous Vadose Zone-(Peer Reviewed Journal) Segal, E., Shouse, P.J., Bradford, S.A. 2009. Deterministic Analysis and Upscaling of Bromide Transport in a Heterogeneous Vadose Zone. Vadose Zone Journal. 8(3):601-610.Modeling the Coupled Effects of Pore Space Geometry and Velocity on Colloid Transport and Retention-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S., Leij, F., Simunek, J., Van Genuchten, M.T. 2009. Modeling the Coupled Effects of Pore Space Geometry and Velocity on Colloid Transport and Retention. Water Resources Research. 45:1-15.Fate of Indicator Microorganisms Under Nutrient Management Plan Conditions-(Peer Reviewed Journal) Bradford, S.A., Segal, E. 2009. Fate of Indicator Microorganisms Under Nutrient Management Plan Conditions. Journal of Environmental Quality. 38:1728-1738.Environmental Impacts and Sustainability of Degraded Water Reuse-(Peer Reviewed Journal) Corwin, D.L., Bradford, S.A. 2008. Environmental Impacts and Sustainability of Degraded Water Reuse. Journal of Environmental Quality. 37:S1-S7.Vadose Zone Modeling:  Introduction and Importance-(Review Article) Simunek, J., Bradford, S.A. 2008. Vadose Zone Modeling:  Introduction and Importance. Vadose Zone Journal.  Vol 7:581-586Cell preparation methods influence Escherichia coli D21g surface chemistry and transport in saturated sand-(Peer Reviewed Journal) Tazehkand, S.S., Torkzaban, S., Bradford, S.A., Walker, S. 2008. Cell preparation methods influence E.coli D21g surface chemistry and transport in saturated sand. Journal of Environmental Quality. 37:2108-2115.Transport and Fate of Bacteria in Porous Media: Coupled Effects of Chemical Conditions and Pore Space Geometry-(Peer Reviewed Journal) Torkzaban, S., Tazehkand, S.S., Walker, S.L., Bradford, S.A. 2008. Transport and Fate of Bacteria in Porous Media: Coupled Effects of Chemical Conditions and Pore Space Geometry. Water Resources Research. Vol 44:1-12Analysis of Steroid Hormones in a Typical Dairy Waste Disposal System-(Peer Reviewed Journal) Zheng, W., Yates, S.R., Bradford, S.A. 2007. Analysis of Steroid Hormones in a Typical Dairy Waste Disposal System. Environmental Science and Technology. Vol 42:2Colloid Transport in Unsaturated Porous Media:  The Role of Water Content and Ionic Strength on Particle Straining-(Peer Reviewed Journal) Torksaban, S., Bradford, S.A., Van Genuchten, M.T., Walker, S.L. 2007. Colloid Transport in Unsaturated Porous Media:  The Role of Water Content and Ionic Strength on Particle Straining. Journal of Contaminant Hydrology. Vol 96:113-127Reuse of concentrated animal feed operation wastewater on agricultural lands-(Peer Reviewed Journal) Bradford, S.A., Segal, E., Zhang, W., Wang, Q. 2008. Reuse of concentrated animal feed operation wastewater on agricultural lands. Journal of Environmental Quality. 37:S97-S115.Resolving the coupled effects of hydrodynamics and DLVO forces on colloid attachment in porous media-(Peer Reviewed Journal) Torkzaban, S., Bradford, S.A., Walker, S.L. 2007. Resolving the coupled effects of hydrodynamics and DLVO forces on colloid attachment in porous media. Langmuir. Vol 23:9652-9660Colloid Transport and Retention in Unsaturated Porous Media: A Review of Interface-Collector, and Pore-Scale Processes and Models-(Peer Reviewed Journal) Bradford, S.A., Torkzaban, S. 2008. Colloid Transport and Retention in Unsaturated Porous Media: A Review of Interface-Collector, and Pore-Scale Processes and Models. Vadose Zone Journal. Vol 7:667-681Integration of Hard and Soft Data to Characterize Field-Scale Hydraulic Properties for Flow and Transport Studies-(Peer Reviewed Journal) Segal, E., Bradford, S.A., Shouse, P.J., Lazarovitch, N., Corwin, D.L. 2008. Integration of Hard and Soft Data to Characterize Field-Scale Hydraulic Properties for Flow and Transport Studies. Vadose Zone Journal. 7(3):878-889.BACTERIA TRANSPORT AND DEPOSITION UNDER UNSATURATED FLOW CONDITIONS: THE ROLE OF WATER CONTENT AND BACTERIA SURFACE HYDROPHOBICITY-(Peer Reviewed Journal) Gargiulo, G., Bradford, S.A., Simunek, J., Ustohal, P., Vereecken, H., Klumpp, E. 2008. Bacteria transport and deposition under unsaturated flow conditions: the role of water content and bacteria surface hydrophobicity. Vadose Zone Journal. Vol 7(2):406-419Coupling of physical and chemical mechanisms of colloid straining in saturated porous media-(Peer Reviewed Journal) Bradford, S.A., Torkzaban2, S., Walker, S.L. 2007. Coupling of physical and chemical mechanisms of colloid straining in saturated porous media. Water Resources Research.  Vol 41:3012-3024A Stochastic Model for Colloid Transport and Deposition-(Peer Reviewed Journal) Bradford, S.A., Toride, N. 2007. A stochastic model for colloid transport and deposition. Journal of Environmental Quality.  Vol 36:1346-1356BACTERIA TRANSPORT AND DEPOSITION UNDER UNSATURATED CONDITIONS: THE ROLE OF THE MATRIX GRAIN SIZE AND THE BACTERIA SURFACE PROTEIN-(Peer Reviewed Journal) Gargiulo, G., Bradford, S.A., Simunek, J., Ustohal, P., Vereecken, H., Klumpp, E. 2007. Bacteria transport and deposition under unsaturated conditions: the role of the matrix grain size and the bacteria surface protein. Journal of Contaminant Hydrology.  Vol 92:255-273TRANSPORT AND DEPOSITION OF METABOLICALLY ACTIVE AND STATIONARY PHASE DEINOCOCCUS RADIODURANS IN UNSATURATED POROUS MEDIA-(Peer Reviewed Journal) Gargiulo, G., Bradford, S.A., Simunek, J., Vereecken, H., Klumpp, E. 2007. Transport and deposition of metabolically active and stationary phase deinococcus radiodurans in unsaturated porous media. Environmental Science and Technology. Vol 41:1265-1271Transport 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. 277-5Transport 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. 182-16Transport and Fate of Nitrate and Pathogens at a Dairy Lagoon Water Application Site-(Abstract Only) Segal, E., Bradford, S.A., Lazarovitch, N., Shouse, P.J. 2006. Transport and Fate of Nitrate and Pathogens at a Dairy Lagoon Water Application Site. American Society of Agronomy Meetings in Indianapolis, IN Nov 12-16, 2006.  CD-ROM.TRANSPORT AND STRAINING OF E. COLI O157:H7 IN SATURATED POROUS MEDIA-(Peer Reviewed Journal) Bradford, S.A., Simunek, J., Walker, S.L. 2006. Transport and straining of E. coli O157:H7 in saturated porous media. Water Resources Research. VOL 42, W12S12SIGNIFICANCE 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, W12S15TRANSPORT 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.)SULFADIMETHOXINE DEGRADATION KINETICS IN MANURE AS AFFECTED BY INITIAL CONCENTRATION, MOISTURE, AND TEMPERATURE-(Peer Reviewed Journal) Wang, Q., Bradford, S.A., Zheng, W., Yates, S.R. 2006. Sulfadimethoxine degradation kinetics in manure as affected by initial concentration, moisture, and temperature. Journal of Environmental Quality.  Vol 35:2162-2169COUPLING OF PHYSICAL AND CHEMICAL MECHANISMS OF COLLOID DEPOSITION-(Abstract Only) Bradford, S.A., Torkzaban, S., Walker, S. 2006. Coupling of physical and chemical mechanisms of colloid deposition. Annual Colloid and Surface Science Symposium. Paper No. 63.COLLOID TRANSPORT IN UNSATURATED POROUS MEDIA: THE ROLE OF WATER CONTENT AND IONIC STRENGTH ON PARTICLE STRAINING-(Abstract Only) Torkzaban, S., Bradford, S.A., Walker, S. 2006. Colloid transport in unsaturated porous media: the role of water content and ionic strength on particle straining. Annual Colloid and Surface Science Symposium. Paper No. 21.A NEW PARADIGM FOR PATHOGEN TRANSPORT AND DEPOSITION IN POROUS MEDIA: THE ROLE OF PORE STRUCTURE AND COLLOID-COLLOID INTERACTIONS-(Abstract Only) Walker, S., Bradford, S.A. 2006. A new paradigm for pathogen transport and deposition in porous media: the role of pore structure and colloid-colloid interactions. Annual Colloid and Surface Science Symposium. Paper No. 14.TRANSPORT OF COLIPHAGE IN THE PRESENCE AND ABSENCE OF MANURE SUSPENSION-(Peer Reviewed Journal) Bradford, S.A., Tadassa, Y.F., Jin, Y. 2006. Transport of coliphage in the presence and absence of manure suspension. Environmental Science and Technology.  VOL 35:1692-1701COLLOID-FACILITATED SOLUTE TRANSPORT IN VARIABLY-SATURATED POROUS MEDIA: NUMERICAL MODEL AND EXPERIMENTAL VERIFICATION-(Peer Reviewed Journal) Simunek, J., He, C., Pang, L., Bradford, S.A. 2006. Colloid-facilitated solute transport in variably-saturated porous media: numerical model and experimental verification. Vadose Zone Journal. Vol 5:1035-1047INTERFACIAL AREA ESTIMATES FOR A NAPL-WATER SYSTEM AND THEIR EFFECT ON PREDICTING GROUNDWATER REMEDIATION EFFICIENCY-(Abstract Only) Wildenschild, D., Bradford, S.A. 2005. Interfacial area estimates for a napl-water system and their effect on predicting groundwater remediation efficiency. EOS Transactions, Fall Meeting. 86:H33A-1372. American Geophysical Union.CONCENTRATION DEPENDENT TRANSPORT OF COLLOIDS IN SATURATED POROUS MEDIA-(Peer Reviewed Journal) Bettahar, M., Bradford, S.A. 2005. Concentration dependent transport of colloids in saturated porous media. Journal of Contaminant Hydrology. 82:99-117.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. 243-4TRANSPORT OF GIARDIA AND MANURE SUSPENSIONS IN SATURATED POROUS MEDIA-(Peer Reviewed Journal) Bradford, S.A., Tadassa, Y.F., Pachepsky, Y.A. 2006. Transport of giardia and manure suspensions in saturated porous media. Journal of Environmental Quality. 35:749-757.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.COLLOID-FACILITATED TRANSPORT IN VARIABLY SATURATED POROUS MEDIA: NUMERICAL MODELING AND EXPERIMENTAL VERIFICATION.-(Abstract Only) He, C., Simunek, J., Pang, L., Bradford, S.A. 2005. Colloid-facilitated transport in variably saturated porous media: numerical modeling and experimental verification. [CD-ROM] Agronomy Abstracts. SSSA Annual Meeting. Salt Lake City, UT.CONCENTRATION DEPENDENT COLLOID TRANSPORT IN SATURATED POROUS MEDIA-(Abstract Only) Bradford, S.A. 2005. Concentration dependent colloid transport in saturated porous media. American Chemical Society Abstracts, San Diego, CA. 229:U646-U647.PREDICTION OF TWO-PHASE CAPILLARY PRESSURE-SATURATION RELATIONSHIPS IN FRACTIONAL WETTABILITY SYSTEMS-(Peer Reviewed Journal) O'Carroll, D.M., Abriola, L.M., Polityka, C.A., Bradford, S.A., Demond, A.H. 2005. Prediction of two-phase capillary pressure-saturation relationships in fractional wettability systems. Journal of Contaminant Hydrology. 77:247-270.STRAINING, ATTACHMENT, AND DETACHMENT OF CRYPTOSPORIDIUM OOCYSTS IN SATURATED POROUS MEDIA-(Peer Reviewed Journal) Bradford, S.A., Bettahar, M. 2005. Straining, attachment, and detachment of Cryptosporidium oocysts in saturated porous media. Journal of Environmental Quality. 34:469-478.TRANSPORT OF MICROORGANISMS IN THE PRESENCE AND ABSENCE OF MANURE SUSPENSIONS-(Abstract Only) Bradford, S.A., Tadassa, Y.F., Bettahar, M. 2004. Transport of microorganisms in the presence and absence of manure suspensions. American Geophysical Union, Abstracts of Fall Meeting, San Francisco, CA. 85:47.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.VOLATILIZATION OF BINARY NAPL MIXTURES IN UNSATURATED POROUS MEDIA-(Peer Reviewed Journal) Abriola, L.M., Bradford, S.A., Lang, J., Gaither, C.L. 2004. Volatilization of binary NAPL mixtures in unsaturated porous media. Vadose Zone Journal. 3:645-655.STRAINING AND ATTACHMENT OF COLLOIDS IN PHYSICALLY HETEROGENEOUS POROUS MEDIA-(Peer Reviewed Journal) Bradford, S.A., Bettahar, M., Simunek, J., Van Genuchten, M.T. 2004. Straining and attachment of colloids in physically heterogeneous porous media. Vadose Zone Journal. 3:384-394.RELEASE OF CRYPTOSPORIDIUM AND GIARDIA FROM DAIRY CATTLE MANURE:  PHYSICAL FACTORS-(Peer Reviewed Journal) Schijven, J.F., Bradford, S.A., Yang, S. 2004. Release of Cryptosporidium and Giardia from dairy cattle manure: Physical factors. Journal of Environmental Quality. 33(4):1499-1508.INFLUENCE OF TEXTURAL AND WETTABILITY VARIATIONS ON PREDICTIONS OF DNAPL PERSISTENCE AND PLUME DEVELOPMENT IN SATURATED POROUS MEDIA-(Peer Reviewed Journal) Phelan, T.J., Lemke, L.D., Bradford, S.A, O'Carroll, D.M., Abriola, L.M. 2004. Influence of textural and wettability variations on predictions of DNAPL persistence and plume development in saturated porous media. Advances in Water Resources. 27:411-427.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.INFILTRATION OF PCE IN A SYSTEM CONTAINING SPATIAL WETTABILITY VARIATIONS-(Peer Reviewed Journal) O'Carroll, D.M., Bradford, S.A., Abriola, L.M. Infiltration of PCE in a system containing spatial wettability variations. Journal of Contaminant Hydrology. 2004. 73:39-63.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.ENTRAPMENT AND DISSOLUTION OF DNAPLS IN PHYSICALLY AND CHEMICALLY          HETEROGENEOUS POROUS MEDIA-(Peer Reviewed Journal) Bradford, S.A., Rathfelder, K.M., Lang, J., Abriola, L.M. 2003. Entrapment and dissolution of DNAPLs in heterogeneous porous media. Journal of Contaminant Hydrology. 67:133-157.TRANSPORT AND FATE OF COLLOIDS IN PHYSICALLY HETEROGENEOUS POROUS MEDIA-(Proceedings)RELEASE OF CRYPTOSPORIDIUM AND GIARDIA FROM DAIRY CALF MANURE: IMPACT OF SOLUTION SALINITY-(Peer Reviewed Journal) Bradford, S.A., Schijven, J. Release of Cryptosporidium and Giardia from Dairy Calf Manure: Impact of Solution Salinity. Journal of Environmental Science and Technology. v. 36. p. 3916-3923.ProjectsSynergistic Managed Aquifer Strategies to Sustain Irrigated Agriculture (CA)Cooperative Agreement (A)Accession Number:439161Improved Agroecosystem Efficiency and Sustainability in a Changing EnvironmentIn-House Appropriated (D)Accession Number:441747The USDA Climate Hubs – Supporting Natural and Working Lands Resilience by Co-Developing and Communicating Research-Informed Agro-Climate PracticesIn-House Appropriated (D)Accession Number:444458Synergistic Managed Aquifer Strategies to Sustain Irrigated AgricultureInteragency Reimbursable Agreement (I)Accession Number:439519Determining Subsurface Hydraulic Properties and Water Content Using Geophysical Methods and Limited Soil/Sediment DatasetsNon-Assistance Cooperative Agreement (S)Accession Number:440857Application of a Watershed Model to Assess Groundwater Sustainability Under Changing Climatic and Management ScenariosNon-Assistance Cooperative Agreement (S)Accession Number:441050Linking Measured Root Zone Dynamics to Atmospheric and Subsurface FluxesNon-Assistance Cooperative Agreement (S)Accession Number:441052Pretreatment Technologies for Managed Aquifer Recharge to Mitigate Clogging and to Remove ContaminantsNon-Assistance Cooperative Agreement (S)Accession Number:441054Nonequilibrium Processes Influencing Contaminant Fate During Managed Aquifer RechargeNon-Assistance Cooperative Agreement (S)Accession Number:443253Assessing the Fate of Metal Oxide Associated Contaminants During Managed Aquifer RechargeNon-Assistance Cooperative Agreement (S)Accession Number:443256Managed Aquifer Recharge to Sustain Irrigated AgricultureNon-Assistance Cooperative Agreement (S)Accession Number:439515Synergistic Managed Aquifer Strategies to Sustain Irrigated Agriculture (NACA)Non-Assistance Cooperative Agreement (S)Accession Number:438927


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