Research Statement

The fate and transport of contaminants in aquatic systems is intertwined with the fate and transport of colloidal materials (biological and non-biological particles in the size range of several nm to several um). Biological colloids include protozoa, bacteria, and viruses; whereas non-biological colloids include mineral precipitants, manufactured colloids, and engineered nanoparticles. Contaminant and colloid fate and transport in the environment is a scientific pursuit that lies at the interface between hydrogeology, geochemistry, biology, and engineering. For more information please see my website at: http://www.earth.utah.edu/people/faculty

Grants, Contracts & Research Gifts

  • HYDRODYNAMIC & CHEMODYNAMIC. PI: JOHNSON,WILLIAM P. STATE OF UTAH, 07/01/2018 - 06/30/2019. Total project budget to date: $57,090.00
  • USGS-DBL-CAUSEWAY. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 07/01/2017 - 06/30/2018. Total project budget to date: $25,000.00
  • METALS IN SAN JUAN RIVER SYST. PI: JOHNSON,WILLIAM P. UT DIVISION OF WATER QUALITY, 01/01/2017 - 01/01/2022. Total project budget to date: $82,000.00
  • COMPLEX HYBRID NANOMATERIALS. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 10/01/2016 - 09/30/2020. Total project budget to date: $320,000.00
  • MAGCORP. PI: JOHNSON,WILLIAM P. RFRIENDS OF GREAT SALT LAKE, 10/01/2016 - 09/30/2019. Total project budget to date: $71,000.00
  • PREDICTIVE TRANSPORT MODEL. PI: JOHNSON,WILLIAM P. US ENVIRONMENTAL PROTECTION AG, 09/01/2016 - 08/31/2019. Total project budget to date: $51,000.00
  • USGS-DBL-CAUSEWAY. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 07/01/2016 - 06/30/2017. Total project budget to date: $25,000.00
  • DEEP BRINE LAYER & MERCURY. PI: JOHNSON,WILLIAM P. WESTMINSTER COLLEGE, 06/15/2016 - 05/31/2018. Total project budget to date: $42,897.00
  • NANO & MICRO-PARTICLE TRANSPRT. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 03/15/2016 - 02/29/2020. Total project budget to date: $270,644.00
  • GSL MONITORING. PI: JOHNSON,WILLIAM P. UT DIVISION OF WATER QUALITY, 12/21/2015 - 12/21/2020. Total project budget to date: $269,750.00
  • MAGCORP. PI: JOHNSON,WILLIAM P. RFRIENDS OF GREAT SALT LAKE, 09/01/2015 - 10/20/2016. Total project budget to date: $25,000.00
  • MATCH FOR 53000737. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 07/01/2015 - 06/30/2016. Total project budget to date: $19,091.00
  • MERCURY BURDENS IN BIOTA. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 07/01/2015 - 06/30/2016. Total project budget to date: $57,857.00
  • MERCURY ISOTOPE SIGNATURES. PI: JOHNSON,WILLIAM P. STATE OF UTAH, 07/01/2013 - 07/31/2014. Total project budget to date: $69,200.00
  • COST SHARE FOR 53000673. PI: JOHNSON,WILLIAM P. STATE OF UTAH, 07/01/2013 - 06/30/2014. Total project budget to date: $10,000.00
  • SCALE UP. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 08/15/2012 - 07/31/2016. Total project budget to date: $220,313.00
  • PARTICIPANT SUPP FOR 58501745. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 08/15/2012 - 07/31/2016. Total project budget to date: $6,900.00
  • TRACE METALS. PI: JOHNSON,WILLIAM P. UT DIVISION OF WATER QUALITY, 08/01/2012 - 09/30/2017. Total project budget to date: $54,500.00
  • TRACE METALS. PI: JOHNSON,WILLIAM P. UT DIVISION OF WATER QUALITY, 08/01/2012 - 09/30/2017. Total project budget to date: $58,400.00
  • TRACE METALS. PI: JOHNSON,WILLIAM P. UT DIVISION OF WATER QUALITY, 08/01/2012 - 09/30/2017. Total project budget to date: $40,000.00
  • NUTRIENT CYCLING. PI: JOHNSON,WILLIAM P. UT DIVISION OF WATER QUALITY, 06/01/2012 - 08/01/2015. Total project budget to date: $216,600.00
  • OISE WORKSHOP. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 04/15/2012 - 03/31/2013. Total project budget to date: $31,350.00
  • SAV-2011. PI: JOHNSON,WILLIAM P. SOUTH DAVIS SEWER DISTRICT, 09/26/2011 - 11/01/2013. Total project budget to date: $74,970.00
  • METHYLATION DEEP BRINE LAYER. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 08/15/2011 - 06/30/2012. Total project budget to date: $29,359.00
  • MATCH FOR 53000611. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 08/15/2011 - 06/30/2012. Total project budget to date: $8,000.00
  • COMPARE PORE WATER TRANSECTS. PI: JOHNSON,WILLIAM P. CENTRAL DAVIS SEWER DISTRICT M, 06/13/2011 - 03/31/2012. Total project budget to date: $21,251.00
  • CELL SURFACE STRUCTURES. PI: JOHNSON,WILLIAM P. ACS PETROLEUM RESEARCH FUND, 01/01/2011 - 08/31/2013. Total project budget to date: $100,000.00
  • SPLITT-BASED DETECTION. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 09/01/2010 - 08/31/2014. Total project budget to date: $427,603.00
  • PART SUPP FOR 58501565. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 09/01/2010 - 08/31/2014. Total project budget to date: $12,000.00
  • METHYLATION BEAR RIVER. PI: JOHNSON,WILLIAM P. TIDES FOUNDATION, 07/01/2010 - 02/28/2011. Total project budget to date: $14,600.00
  • SAV. PI: JOHNSON,WILLIAM P. SOUTH VALLEY WATER RECLAMATION, 04/01/2010 - 05/31/2012. Total project budget to date: $57,500.00
  • MERCURY ECUADOR. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 03/01/2010 - 03/31/2011. Total project budget to date: $15,500.00
  • MATCH FOR 53000523. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 07/01/2009 - 06/30/2010. Total project budget to date: $8,000.00
  • MERCURY METHYLATION IN FB. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF NATURAL RESOU, 07/01/2009 - 06/30/2010. Total project budget to date: $37,400.00
  • SPLITT SEED. PI: JOHNSON,WILLIAM P. UNIVERSITY OF UTAH RESEARCH FO, 06/01/2009 - 05/31/2010. Total project budget to date: $22,400.00
  • NP IN AGRICULTURE. PI: JOHNSON,WILLIAM P. UTAH STATE UNIVERSITY, 01/01/2009 - 12/31/2011. Total project budget to date: $154,735.00
  • NEW FILTRATION THEORY. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 08/01/2008 - 07/31/2013. Total project budget to date: $428,594.00
  • SNOWPACK MERCURY. PI: JOHNSON,WILLIAM P. STATE OF UTAH, 10/01/2007 - 09/30/2008. Total project budget to date: $23,000.00
  • MATCH FOR 53000488. PI: JOHNSON,WILLIAM P. UT DEPARTMENT OF ENVIRONMENTAL, 10/01/2007 - 09/30/2008. Total project budget to date: $10,000.00
  • MINE LANDS TAILINGS. PI: JOHNSON,WILLIAM P. DOI US GEOLOGICAL SURVEY, 08/17/2007 - 09/30/2008. Total project budget to date: $10,000.00
  • PATHOGEN DEPOSITION AND TRANSP. PI: JOHNSON,WILLIAM P. US DEPARTMENT OF AGRICULTURE, 09/28/2006 - 08/31/2009. Total project budget to date: $150,116.00
  • ABANDONED MINE LANDS TALINGS. PI: JOHNSON,WILLIAM P. DOI US GEOLOGICAL SURVEY, 09/13/2006 - 06/30/2007. Total project budget to date: $13,000.00
  • GWUDI. PI: JOHNSON,WILLIAM P. ARIZONA STATE UNIVERSITY, 08/01/2006 - 04/01/2010. Total project budget to date: $109,968.00
  • MATCH FOR 54501438. PI: JOHNSON,WILLIAM P. ARIZONA STATE UNIVERSITY, 08/01/2006 - 08/01/2009. Total project budget to date: $22,000.00
  • FLUX DWQ-SE. PI: JOHNSON,WILLIAM P. CH2M HILL LTD, 05/15/2006 - 09/30/2008. Total project budget to date: $363,525.00
  • LOADS DWQ-SE. PI: JOHNSON,WILLIAM P. CH2M HILL LTD, 04/03/2006 - 09/30/2008. Total project budget to date: $164,073.00
  • DEVELOPMENT OF A CONCEPTUAL MO. PI: Co-PI(s): JOHNSON,WILLIAM P. UT DIVISION OF WATER QUALITY, 10/01/2005 - 02/01/2006. Total project budget to date: $20,000.00
  • PORE-SCALE PROCESS/POROUS MEDI. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 03/01/2004 - 02/28/2008. Total project budget to date: $399,997.00
  • MATCH FOR 58500997. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 02/15/2004 - 01/31/2007. Total project budget to date: $134,761.00
  • COLLOID-SUBSTREAM INTERACTION. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 02/15/2004 - 01/31/2007. Total project budget to date: $314,442.00
  • ANALYSIS OF WATER FOR BACTERIA. PI: Co-PI(s): JOHNSON,WILLIAM P. DEPT OF INTERIOR GEO SURVEY, 09/02/2003 - 12/01/2003. Total project budget to date: $2,000.00
  • US SWISS COOP/ LINK POROUS MED. PI: Co-PI(s): JOHNSON,WILLIAM P. NATL SCIENCE FNDN, 02/01/2003 - 04/30/2004. Total project budget to date: $54,800.00
  • HUMIC ACID. PI: Co-PI(s): JOHNSON,WILLIAM P. UNIV OF UTAH RES FNDN, 11/01/2002 - 10/31/2004. Total project budget to date: $28,000.00
  • AQUATIC NUISANCES. PI: Co-PI(s): JOHNSON,WILLIAM P. OLD DOMINION UNIV, 10/01/2002 - 06/30/2004. Total project budget to date: $32,185.00
  • MAND MATCH 54500980. PI: Co-PI(s): JOHNSON,WILLIAM P. OLD DOMINION UNIV, 10/01/2002 - 06/30/2004. Total project budget to date: $10,733.00
  • AQUATIC NUISANCES. PI: Co-PI(s): JOHNSON,WILLIAM P. OLD DOMINION UNIV, 10/01/2001 - 04/30/2003. Total project budget to date: $32,185.00
  • MAND MATCH 54500844. PI: Co-PI(s): JOHNSON,WILLIAM P. OLD DOMINION UNIV, 10/01/2001 - 04/30/2003. Total project budget to date: $10,733.00
  • RETARDATION OF BACTERIA. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 01/02/2001 - 03/31/2006. Total project budget to date: $299,617.00
  • REU SUPP TO 58500718. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 01/02/2001 - 03/31/2006. Total project budget to date: $18,258.00
  • MATCH FOR 58500718. PI: JOHNSON,WILLIAM P. NATIONAL SCIENCE FOUNDATION, 01/02/2001 - 03/31/2006. Total project budget to date: $20,000.00
  • FERROGRAPHIC CAPTURE. PI: Co-PI(s): JOHNSON,WILLIAM P. BRIGHAM YOUNG UNIV, 09/15/2000 - 03/15/2001. Total project budget to date: $4,999.00
  • M AND MATCH 53000223. PI: Co-PI(s): JOHNSON,WILLIAM P. UTAH DEPT OF ENV QUALITY, 09/01/1999 - 06/15/2004. Total project budget to date: $5,000.00
  • MATCH FOR 53000223. PI: Co-PI(s): JOHNSON,WILLIAM P. UTAH DEPT ENVIRONMENTAL QUALIT, 09/01/1999 - 06/15/2004. Total project budget to date: $5,000.00
  • UT DEPT OF ENV QUALITY. PI: Co-PI(s): JOHNSON,WILLIAM P. UTAH DEPT OF ENV QUALITY, 09/01/1999 - 06/15/2004. Total project budget to date: $98,000.00
  • FERROGRAPHIC TRACKING. PI: Co-PI(s): JOHNSON,WILLIAM P. DEPT OF ENERGY OAKLAND, 05/03/1999 - 07/31/2002. Total project budget to date: $244,273.00
  • M-MATCH 55300022. PI: Co-PI(s): JOHNSON,WILLIAM P. ENVIRONMENTAL PROTECT AG EPA, 09/01/1998 - 08/31/2002. Total project budget to date: $40,000.00
  • HUMIC SUBSTANCES. PI: Co-PI(s): JOHNSON,WILLIAM P. ENVIRONMENTAL PROTECT AG EPA, 09/01/1998 - 08/31/2002. Total project budget to date: $285,595.00
  • PREG-ROBBING OF GOLD. PI: Co-PI(s): JOHNSON,WILLIAM P. BARRICK GOLDSTRIKE MINES INC, 07/18/1997 - 01/01/2000. Total project budget to date: $81,336.86
  • MATCH FOR 5-38924. PI: Co-PI(s): JOHNSON,WILLIAM P. NATL SCIENCE FNDN, 07/01/1997 - 06/30/1998. Total project budget to date: $5,000.00
  • COLLOIDAL MATERIAL COLLECTION. PI: Co-PI(s): JOHNSON,WILLIAM P. NATL SCIENCE FNDN, 07/01/1997 - 06/30/1998. Total project budget to date: $12,000.00
  • MAGNETIC SEPARATION OF COLLOID. PI: Co-PI(s): JOHNSON,WILLIAM P. UNIV OF UTAH RES FNDN, 04/01/1997 - 08/31/1998. Total project budget to date: $29,421.00
  • GOLDSTRIKE ORE-CARBONACEOUS. PI: Co-PI(s): JOHNSON,WILLIAM P. OTHER PRIVATE, 08/14/1995 - 03/31/1998. Total project budget to date: $64,057.14

Geographical Regions of Interest

  • China
  • Ecuador
    Please see publications in CV.
  • Pakistan
  • Uganda
    please see publications in CV.

Software Titles

  • Parti-Suite. Nano- and Micro-Particle Transport and Surface Interaction from Pore to Continuum Scale in Granular Media. Release Date: 07/01/2019.

Publications

  • VanNess K, Rasmuson A, Ron CA & Johnson WP (2020). A Unified Force and Torque Balance for Colloid Transport: Predicting Attachment and Mobilization under Favorable and Unfavorable Conditions. Langmuir : the ACS journal of surfaces and colloids. Vol. 35, 9061-9070. Published, 03/01/2020.
  • VanNess K, Rasmuson A, Ron CA & Johnson WP (2020). A Unified Force and Torque Balance for Colloid Transport: Predicting Attachment and Mobilization under Favorable and Unfavorable Conditions. Langmuir : the ACS journal of surfaces and colloids. Vol. 35, 9061-9070. Published, 03/01/2020.
  • Hilpert M & Johnson WP (2020). A binomial modeling approach for upscaling colloid transport under unfavorable attachment conditions: Emergent prediction of non-monotonic retention profiles. Water resources research. Vol. 54, 46-60. Published, 02/01/2020.
  • Hilpert M & Johnson WP (2020). A binomial modeling approach for upscaling colloid transport under unfavorable attachment conditions: Emergent prediction of non-monotonic retention profiles. Water resources research. Vol. 54, 46-60. Published, 02/01/2020.
  • Johnson WP, Rasmuson A, Pazmiño E & Hilpert M (2019). Why Variant Colloid Transport Behaviors Emerge among Identical Individuals in Porous Media When Colloid-Surface Repulsion Exists. Environmental science & technology. Vol. 52, 7230-7239. Published, 09/01/2019.
  • Rasmuson A, VanNess K, Ron CA & Johnson WP (2019). Hydrodynamic versus Surface Interaction Impacts of Roughness in Closing the Gap between Favorable and Unfavorable Colloid Transport Conditions. Environmental science & technology. Vol. 53, 2450-2459. Published, 09/01/2019.
  • Johnson WP, Rasmuson A, Pazmiño E & Hilpert M (2019). Why Variant Colloid Transport Behaviors Emerge among Identical Individuals in Porous Media When Colloid-Surface Repulsion Exists. Environmental science & technology. Vol. 52, 7230-7239. Published, 09/01/2019.
  • Rasmuson A, VanNess K, Ron CA & Johnson WP (2019). Hydrodynamic versus Surface Interaction Impacts of Roughness in Closing the Gap between Favorable and Unfavorable Colloid Transport Conditions. Environmental science & technology. Vol. 53, 2450-2459. Published, 09/01/2019.
  • Valdes C, Black FJ, Stringham B, Collins JN, Goodman JR, Saxton HJ, Mansfield CR, Schmidt JN, Yang S & Johnson WP (2017). Total Mercury and Methylmercury Response in Water, Sediment, and Biota to Destratification of the Great Salt Lake, Utah, United States. Environmental science & technology. Vol. 51, 4887-4896. Published, 06/01/2017.
  • Rasmuson A, Pazmino E, Assemi S & Johnson WP (2017). Contribution of Nano- to Microscale Roughness to Heterogeneity: Closing the Gap between Unfavorable and Favorable Colloid Attachment Conditions. Environmental science & technology. Vol. 51, 2151-2160. Published, 06/01/2017.
  • Rasmuson A, Pazmino E, Assemi S & Johnson WP (2017). Contribution of Nano- to Microscale Roughness to Heterogeneity: Closing the Gap between Unfavorable and Favorable Colloid Attachment Conditions. Environmental science & technology. Vol. 51, 2151-2160. Published, 06/01/2017.
  • Valdes C, Black FJ, Stringham B, Collins JN, Goodman JR, Saxton HJ, Mansfield CR, Schmidt JN, Yang S & Johnson WP (2017). Total Mercury and Methylmercury Response in Water, Sediment, and Biota to Destratification of the Great Salt Lake, Utah, United States. Environmental science & technology. Vol. 51, 4887-4896. Published, 06/01/2017.
  • Frederick L, VanDerslice J, Taddie M, Malecki K, Gregg J, Faust N & Johnson WP (2016). Contrasting regional and national mechanisms for predicting elevated arsenic in private wells across the United States using classification and regression trees. Water research. Vol. 91, 295-304. Published, 11/01/2016.
  • Frederick L, VanDerslice J, Taddie M, Malecki K, Gregg J, Faust N & Johnson WP (2016). Contrasting regional and national mechanisms for predicting elevated arsenic in private wells across the United States using classification and regression trees. Water research. Vol. 91, 295-304. Published, 11/01/2016.
  • Trauscht J, Pazmino E & Johnson WP (2016). Prediction of Nanoparticle and Colloid Attachment on Unfavorable Mineral Surfaces Using Representative Discrete Heterogeneity. Langmuir : the ACS journal of surfaces and colloids. Vol. 31, 9366-78. Published, 05/01/2016.
  • Trauscht J, Pazmino E & Johnson WP (2016). Prediction of Nanoparticle and Colloid Attachment on Unfavorable Mineral Surfaces Using Representative Discrete Heterogeneity. Langmuir : the ACS journal of surfaces and colloids. Vol. 31, 9366-78. Published, 05/01/2016.
  • Johnson WP, Frederick LE, Millington MR, Vala D, Reese BK, Freedman DR, Stenten CJ, Trauscht JS, Tingey CE, Kip Solomon D, Fernandez DP & Bowen GJ (2016). Potential impacts to perennial springs from tar sand mining, processing, and disposal on the Tavaputs Plateau, Utah, USA. The Science of the total environment. Vol. 532, 20-30. Published, 03/01/2016.
  • Johnson WP, Frederick LE, Millington MR, Vala D, Reese BK, Freedman DR, Stenten CJ, Trauscht JS, Tingey CE, Kip Solomon D, Fernandez DP & Bowen GJ (2016). Potential impacts to perennial springs from tar sand mining, processing, and disposal on the Tavaputs Plateau, Utah, USA. The Science of the total environment. Vol. 532, 20-30. Published, 03/01/2016.
  • Pazmino E, Trauscht J & Johnson WP (2015). Release of colloids from primary minimum contact under unfavorable conditions by perturbations in ionic strength and flow rate. Environmental science & technology. Vol. 48, 9227-35. Published, 10/01/2015.
  • Pazmino E, Trauscht J & Johnson WP (2015). Release of colloids from primary minimum contact under unfavorable conditions by perturbations in ionic strength and flow rate. Environmental science & technology. Vol. 48, 9227-35. Published, 10/01/2015.
  • Johnson WP, Swanson N, Black B, Rudd A, Carling G, Fernandez DP, Luft J, Van Leeuwen J & Marvin-DiPasquale M (2015). Total- and methyl-mercury concentrations and methylation rates across the freshwater to hypersaline continuum of the Great Salt Lake, Utah, USA. The Science of the total environment. Vol. 511, 489-500. Published, 08/01/2015.
  • Johnson WP, Swanson N, Black B, Rudd A, Carling G, Fernandez DP, Luft J, Van Leeuwen J & Marvin-DiPasquale M (2015). Total- and methyl-mercury concentrations and methylation rates across the freshwater to hypersaline continuum of the Great Salt Lake, Utah, USA. The Science of the total environment. Vol. 511, 489-500. Published, 08/01/2015.
  • Petersen KE, Manangon E, Hood JL, Wickline SA, Fernandez DP, Johnson WP & Gale BK (2015). A review of exosome separation techniques and characterization of B16-F10 mouse melanoma exosomes with AF4-UV-MALS-DLS-TEM. Analytical and bioanalytical chemistry. Vol. 406, 7855-66. Published, 07/01/2015.
  • Petersen KE, Manangon E, Hood JL, Wickline SA, Fernandez DP, Johnson WP & Gale BK (2015). A review of exosome separation techniques and characterization of B16-F10 mouse melanoma exosomes with AF4-UV-MALS-DLS-TEM. Analytical and bioanalytical chemistry. Vol. 406, 7855-66. Published, 07/01/2015.
  • Pazmino E, Trauscht J, Dame B & Johnson WP (2015). Power law size-distributed heterogeneity explains colloid retention on soda lime glass in the presence of energy barriers. Langmuir : the ACS journal of surfaces and colloids. Vol. 30, 5412-21. Published, 04/01/2015.
  • Pazmino E, Trauscht J, Dame B & Johnson WP (2015). Power law size-distributed heterogeneity explains colloid retention on soda lime glass in the presence of energy barriers. Langmuir : the ACS journal of surfaces and colloids. Vol. 30, 5412-21. Published, 04/01/2015.
  • Tasci TO, Johnson WP, Fernandez DP, Manangon E & Gale BK (2014). Circuit modification in electrical field flow fractionation systems generating higher resolution separation of nanoparticles. Journal of chromatography. A. Vol. 1365, 164-72. Published, 12/01/2014.
  • Tasci TO, Johnson WP, Fernandez DP, Manangon E & Gale BK (2014). Circuit modification in electrical field flow fractionation systems generating higher resolution separation of nanoparticles. Journal of chromatography. A. Vol. 1365, 164-72. Published, 12/01/2014.
  • Tasci TO, Johnson WP, Fernandez DP, Manangon E & Gale BK (2014). Biased cyclical electrical field flow fractionation for separation of sub 50 nm particles. Analytical chemistry. Vol. 85, 11225-32. Published, 08/01/2014.
  • Tasci TO, Johnson WP, Fernandez DP, Manangon E & Gale BK (2014). Biased cyclical electrical field flow fractionation for separation of sub 50 nm particles. Analytical chemistry. Vol. 85, 11225-32. Published, 08/01/2014.
  • Ma H, Hradisky M & Johnson WP (2014). Extending applicability of correlation equations to predict colloidal retention in porous media at low fluid velocity. Environmental science & technology. Vol. 47, 2272-8. Published, 06/01/2014.
  • Ma H, Hradisky M & Johnson WP (2014). Extending applicability of correlation equations to predict colloidal retention in porous media at low fluid velocity. Environmental science & technology. Vol. 47, 2272-8. Published, 06/01/2014.
  • Carling GT, Richards DC, Hoven H, Miller T, Fernandez DP, Rudd A, Pazmino E & Johnson WP (2013). Relationships of surface water, pore water, and sediment chemistry in wetlands adjacent to Great Salt Lake, Utah, and potential impacts on plant community health. The Science of the total environment. Vol. 443, 798-811. Published, 07/01/2013.
  • Carling GT, Fernandez DP & Johnson WP (2012). Dust-mediated loading of trace and major elements to Wasatch Mountain snowpack. The Science of the total environment. Vol. 432, 65-77. Published, 12/01/2012.
  • Carling GT, Fernandez DP & Johnson WP (2012). Dust-mediated loading of trace and major elements to Wasatch Mountain snowpack. The Science of the total environment. Vol. 432, 65-77. Published, 12/01/2012.
  • Johnson WP & Amy GL (2012). Facilitated transport and enhanced desorption of polycyclic aromatic hydrocarbons by natural organic matter in aquifer sediments. Environmental science & technology. Vol. 29, 807-17. Published, 10/01/2012.
  • Dimkpa CO, McLean JE, Britt DW, Johnson WP, Arey B, Lea AS & Anderson AJ (2012). Nanospecific inhibition of pyoverdine siderophore production in Pseudomonas chlororaphis O6 by CuO nanoparticles. Chemical research in toxicology. Vol. 25, 1066-74. Published, 09/01/2012.
  • Dimkpa CO, McLean JE, Britt DW, Johnson WP, Arey B, Lea AS & Anderson AJ (2012). Nanospecific inhibition of pyoverdine siderophore production in Pseudomonas chlororaphis O6 by CuO nanoparticles. Chemical research in toxicology. Vol. 25, 1066-74. Published, 09/01/2012.
  • Ma H, Pazmino E & Johnson WP (2012). Surface heterogeneity on hemispheres-in-cell model yields all experimentally-observed non-straining colloid retention mechanisms in porous media in the presence of energy barriers. Langmuir : the ACS journal of surfaces and colloids. Vol. 27, 14982-94. Published, 04/01/2012.
  • Pazmino EF, Ma H & Johnson WP (2012). Applicability of colloid filtration theory in size-distributed, reduced porosity, granular media in the absence of energy barriers. Environmental science & technology. Vol. 45, 10401-7. Published, 04/01/2012.
  • Pazmino EF, Ma H & Johnson WP (2012). Applicability of colloid filtration theory in size-distributed, reduced porosity, granular media in the absence of energy barriers. Environmental science & technology. Vol. 45, 10401-7. Published, 04/01/2012.
  • Ma H, Pazmino E & Johnson WP (2012). Surface heterogeneity on hemispheres-in-cell model yields all experimentally-observed non-straining colloid retention mechanisms in porous media in the presence of energy barriers. Langmuir : the ACS journal of surfaces and colloids. Vol. 27, 14982-94. Published, 04/01/2012.
  • Deubner DC, Sabey P, Huang W, Fernandez D, Rudd A, Johnson WP, Storrs J & Larson R (2012). Solubility and chemistry of materials encountered by beryllium mine and ore extraction workers: relation to risk. Journal of occupational and environmental medicine. Vol. 53, 1187-93. Published, 02/01/2012.
  • Deubner DC, Sabey P, Huang W, Fernandez D, Rudd A, Johnson WP, Storrs J & Larson R (2012). Solubility and chemistry of materials encountered by beryllium mine and ore extraction workers: relation to risk. Journal of occupational and environmental medicine. Vol. 53, 1187-93. Published, 02/01/2012.
  • Ma H, Pazmino EF & Johnson WP (2012). Gravitational settling effects on unit cell predictions of colloidal retention in porous media in the absence of energy barriers. Environmental science & technology. Vol. 45, 8306-12. Published, 01/01/2012.
  • Ma H, Pazmino EF & Johnson WP (2012). Gravitational settling effects on unit cell predictions of colloidal retention in porous media in the absence of energy barriers. Environmental science & technology. Vol. 45, 8306-12. Published, 01/01/2012.
  • Huang W, Fernandez D, Rudd A, Johnson WP, Deubner D, Sabey P, Storrs J & Larsen R (2011). Dissolution and nanoparticle generation behavior of Be-associated materials in synthetic lung fluid using inductively coupled plasma mass spectroscopy and flow field-flow fractionation. Journal of chromatography. A. Vol. 1218, 4149-59. Published, 09/01/2011.
  • Huang W, Fernandez D, Rudd A, Johnson WP, Deubner D, Sabey P, Storrs J & Larsen R (2011). Dissolution and nanoparticle generation behavior of Be-associated materials in synthetic lung fluid using inductively coupled plasma mass spectroscopy and flow field-flow fractionation. Journal of chromatography. A. Vol. 1218, 4149-59. Published, 09/01/2011.
  • Johnson WP, Ma H & Pazmino E (2011). Straining credibility: a general comment regarding common arguments used to infer straining as the mechanism of colloid retention in porous media. Environmental science & technology. Vol. 45, 3831-2. Published, 08/01/2011.
  • Isunju JB, Schwartz K, Schouten MA, Johnson WP & van Dijk MP (2011). Socio-economic aspects of improved sanitation in slums: a review. Public health. Vol. 125, 368-76. Published, 08/01/2011.
  • Johnson WP, Ma H & Pazmino E (2011). Straining credibility: a general comment regarding common arguments used to infer straining as the mechanism of colloid retention in porous media. Environmental science & technology. Vol. 45, 3831-2. Published, 08/01/2011.
  • Isunju JB, Schwartz K, Schouten MA, Johnson WP & van Dijk MP (2011). Socio-economic aspects of improved sanitation in slums: a review. Public health. Vol. 125, 368-76. Published, 08/01/2011.
  • Dimkpa CO, Calder A, Gajjar P, Merugu S, Huang W, Britt DW, McLean JE, Johnson WP & Anderson AJ (2011). Interaction of silver nanoparticles with an environmentally beneficial bacterium, Pseudomonas chlororaphis. Journal of hazardous materials. Vol. 188, 428-35. Published, 07/01/2011.
  • Dimkpa CO, Calder A, Gajjar P, Merugu S, Huang W, Britt DW, McLean JE, Johnson WP & Anderson AJ (2011). Interaction of silver nanoparticles with an environmentally beneficial bacterium, Pseudomonas chlororaphis. Journal of hazardous materials. Vol. 188, 428-35. Published, 07/01/2011.
  • Johnson WP, Pazmino E & Ma H (2010). Direct observations of colloid retention in granular media in the presence of energy barriers, and implications for inferred mechanisms from indirect observations. Water research. Vol. 44, 1158-69. Published, 05/01/2010.
  • Johnson WP, Pazmino E & Ma H (2010). Direct observations of colloid retention in granular media in the presence of energy barriers, and implications for inferred mechanisms from indirect observations. Water research. Vol. 44, 1158-69. Published, 05/01/2010.
  • Ma H & Johnson WP (2010). Colloid retention in porous media of various porosities: predictions by the hemispheres-in-cell model. Langmuir : the ACS journal of surfaces and colloids. Vol. 26, 1680-7. Published, 03/01/2010.
  • Ma H & Johnson WP (2010). Colloid retention in porous media of various porosities: predictions by the hemispheres-in-cell model. Langmuir : the ACS journal of surfaces and colloids. Vol. 26, 1680-7. Published, 03/01/2010.
  • Ma H, Pedel J, Fife P & Johnson WP (2010). Hemispheres-in-cell geometry to predict colloid deposition in porous media. Environmental science & technology. Vol. 43, 8573-9. Published, 01/01/2010.
  • Ma H, Pedel J, Fife P & Johnson WP (2010). Hemispheres-in-cell geometry to predict colloid deposition in porous media. Environmental science & technology. Vol. 43, 8573-9. Published, 01/01/2010.
  • Beisner K, Naftz DL, Johnson WP & Diaz X (2009). Selenium and trace element mobility affected by periodic displacement of stratification in the Great Salt Lake, Utah. The Science of the total environment. Vol. 407, 5263-73. Published, 09/01/2009.
  • Beisner K, Naftz DL, Johnson WP & Diaz X (2009). Selenium and trace element mobility affected by periodic displacement of stratification in the Great Salt Lake, Utah. The Science of the total environment. Vol. 407, 5263-73. Published, 09/01/2009.
  • Diaz X, Johnson WP & Naftz DL (2009). Selenium mass balance in the Great Salt Lake, Utah. The Science of the total environment. Vol. 407, 2333-41. Published, 04/01/2009.
  • Diaz X, Johnson WP & Naftz DL (2009). Selenium mass balance in the Great Salt Lake, Utah. The Science of the total environment. Vol. 407, 2333-41. Published, 04/01/2009.
  • Gupta V, Johnson WP, Shafieian P, Ryu H, Alum A, Abbaszadegan M, Hubbs SA & Rauch-Williams T (2009). Riverbank filtration: comparison of pilot scale transport with theory. Environmental science & technology. Vol. 43, 669-76. Published, 03/01/2009.
  • Diaz X, Johnson WP, Oliver WA & Naftz DL (2009). Volatile selenium flux from the Great Salt Lake, Utah. Environmental science & technology. Vol. 43, 53-9. Published, 03/01/2009.
  • Diaz X, Johnson WP, Oliver WA & Naftz DL (2009). Volatile selenium flux from the Great Salt Lake, Utah. Environmental science & technology. Vol. 43, 53-9. Published, 03/01/2009.
  • Gupta V, Johnson WP, Shafieian P, Ryu H, Alum A, Abbaszadegan M, Hubbs SA & Rauch-Williams T (2009). Riverbank filtration: comparison of pilot scale transport with theory. Environmental science & technology. Vol. 43, 669-76. Published, 03/01/2009.
  • Tong M, ma H & Johnson WP (2008). Funneling of flow into grain-to-grain contacts drives colloid-colloid aggregation in the presence of an energy barrier. Environmental science & technology. Vol. 42, 2826-32. Published, 07/01/2008.
  • Tong M, ma H & Johnson WP (2008). Funneling of flow into grain-to-grain contacts drives colloid-colloid aggregation in the presence of an energy barrier. Environmental science & technology. Vol. 42, 2826-32. Published, 07/01/2008.
  • Johnson WP, Li X & Yal G (2007). Colloid retention in porous media: mechanistic confirmation of wedging and retention in zones of flow stagnation. Environmental science & technology. Vol. 41, 1279-87. Published, 08/01/2007.
  • Johnson WP, Li X & Yal G (2007). Colloid retention in porous media: mechanistic confirmation of wedging and retention in zones of flow stagnation. Environmental science & technology. Vol. 41, 1279-87. Published, 08/01/2007.
  • Assemi S, Nalaskowski J, Miller JD & Johnson WP (2007). Isoelectric point of fluorite by direct force measurements using atomic force microscopy. Langmuir : the ACS journal of surfaces and colloids. Vol. 22, 1403-5. Published, 05/01/2007.
  • Johnson WP & Li X (2007). Comment on breakdown of colloid filtration theory: role of the secondary energy minimum and surface charge heterogeneities. (pp. 10895; author reply 10896-7). Vol. 21. Langmuir : the ACS journal of surfaces and colloids. Published, 05/01/2007.
  • Assemi S, Nalaskowski J, Miller JD & Johnson WP (2007). Isoelectric point of fluorite by direct force measurements using atomic force microscopy. Langmuir : the ACS journal of surfaces and colloids. Vol. 22, 1403-5. Published, 05/01/2007.
  • Johnson WP & Li X (2007). Comment on breakdown of colloid filtration theory: role of the secondary energy minimum and surface charge heterogeneities. (pp. 10895; author reply 10896-7). Vol. 21. Langmuir : the ACS journal of surfaces and colloids. Published, 05/01/2007.
  • Tong M & Johnson WP (2007). Colloid population heterogeneity drives hyperexponential deviation from classic filtration theory. (pp. 493-9). Vol. 41. Environmental science & technology. Published, 03/01/2007.
  • Tong M & Johnson WP (2007). Colloid population heterogeneity drives hyperexponential deviation from classic filtration theory. (pp. 493-9). Vol. 41. Environmental science & technology. Published, 03/01/2007.
  • Johnson WP (2007). Comment on Pang et al. (2005) Filtration and transport of Bacillus subtilis spores and the F-RNA phage MS2 in a coarse alluvial gravel aquifer: implications in the estimation of setback distances. (pp. 160-1; discussion 162). Vol. 86. Journal of contaminant hydrology. Published, 01/01/2007.
  • Johnson WP & Tong M (2007). Observed and simulated fluid drag effects on colloid deposition in the presence of an energy barrier in an impinging jet system. Environmental science & technology. Vol. 40, 5015-21. Published, 01/01/2007.
  • Johnson WP (2007). Comment on Pang et al. (2005) Filtration and transport of Bacillus subtilis spores and the F-RNA phage MS2 in a coarse alluvial gravel aquifer: implications in the estimation of setback distances. (pp. 160-1; discussion 162). Vol. 86. Journal of contaminant hydrology. Published, 01/01/2007.
  • Johnson WP & Tong M (2007). Observed and simulated fluid drag effects on colloid deposition in the presence of an energy barrier in an impinging jet system. Environmental science & technology. Vol. 40, 5015-21. Published, 01/01/2007.
  • Li X, Lin CL, Miller JD & Johnson WP (2006). Pore-scale observation of microsphere deposition at grain-to-grain contacts over assemblage-scale porous media domains using X-ray microtomography. Environmental science & technology. Vol. 40, 3762-8. Published, 11/01/2006.
  • Li X, Lin CL, Miller JD & Johnson WP (2006). Role of grain-to-grain contacts on profiles of retained colloids in porous media in the presence of an energy barrier to deposition. Environmental science & technology. Vol. 40, 3769-74. Published, 11/01/2006.
  • Li X, Lin CL, Miller JD & Johnson WP (2006). Pore-scale observation of microsphere deposition at grain-to-grain contacts over assemblage-scale porous media domains using X-ray microtomography. Environmental science & technology. Vol. 40, 3762-8. Published, 11/01/2006.
  • Li X, Lin CL, Miller JD & Johnson WP (2006). Role of grain-to-grain contacts on profiles of retained colloids in porous media in the presence of an energy barrier to deposition. Environmental science & technology. Vol. 40, 3769-74. Published, 11/01/2006.
  • Dong H, Scheibe TD, Johnson WP, Monkman CM & Fuller ME (2006). Change of collision efficiency with distance in bacterial transport experiments. Ground water. Vol. 44, 415-29. Published, 09/01/2006.
  • Dong H, Scheibe TD, Johnson WP, Monkman CM & Fuller ME (2006). Change of collision efficiency with distance in bacterial transport experiments. Ground water. Vol. 44, 415-29. Published, 09/01/2006.
  • Li X, Zhang P, Lin CL & Johnson WP (2005). Role of hydrodynamic drag on microsphere deposition and re-entrainment in porous media under unfavorable conditions. Environmental science & technology. Vol. 39, 4012-20. Published, 10/01/2005.
  • Li X, Zhang P, Lin CL & Johnson WP (2005). Role of hydrodynamic drag on microsphere deposition and re-entrainment in porous media under unfavorable conditions. Environmental science & technology. Vol. 39, 4012-20. Published, 10/01/2005.
  • Tong M, Camesano TA & Johnson WP (2005). Spatial variation in deposition rate coefficients of an adhesion-deficient bacterial strain in quartz sand. Environmental science & technology. Vol. 39, 3679-87. Published, 09/01/2005.
  • Tong M, Camesano TA & Johnson WP (2005). Spatial variation in deposition rate coefficients of an adhesion-deficient bacterial strain in quartz sand. Environmental science & technology. Vol. 39, 3679-87. Published, 09/01/2005.
  • Tong M, Li X, Brow CN & Johnson WP (2005). Detachment-influenced transport of an adhesion-deficient bacterial strain within water-reactive porous media. Environmental science & technology. Vol. 39, 2500-8. Published, 08/01/2005.
  • Tong M, Li X, Brow CN & Johnson WP (2005). Detachment-influenced transport of an adhesion-deficient bacterial strain within water-reactive porous media. Environmental science & technology. Vol. 39, 2500-8. Published, 08/01/2005.
  • Li X & Johnson WP (2005). Nonmonotonic variations in deposition rate coefficients of microspheres in porous media under unfavorable deposition conditions. Environmental science & technology. Vol. 39, 1658-65. Published, 07/01/2005.
  • Li X & Johnson WP (2005). Nonmonotonic variations in deposition rate coefficients of microspheres in porous media under unfavorable deposition conditions. Environmental science & technology. Vol. 39, 1658-65. Published, 07/01/2005.
  • Li X, Scheibe TD & Johnson WP (2005). Apparent decreases in colloid deposition rate coefficients with distance of transport under unfavorable deposition conditions: a general phenomenon. (pp. 5616-25). Vol. 38. Environmental science & technology. Published, 03/01/2005.
  • Li X, Scheibe TD & Johnson WP (2005). Apparent decreases in colloid deposition rate coefficients with distance of transport under unfavorable deposition conditions: a general phenomenon. (pp. 5616-25). Vol. 38. Environmental science & technology. Published, 03/01/2005.
  • Fuller ME, Mailloux BJ, Streger SH, Hall JA, Zhang P, Kovacik WP, Vainberg S, Johnson WP, Onstott TC & DeFlaun MF (2004). Application of a vital fluorescent staining method for simultaneous, near-real-time concentration monitoring of two bacterial strains in an Atlantic coastal plain aquifer in Oyster, Virginia. (pp. 1680-7). Vol. 70. Applied and environmental microbiology. Published, 05/01/2004.
  • Fuller ME, Mailloux BJ, Streger SH, Hall JA, Zhang P, Kovacik WP, Vainberg S, Johnson WP, Onstott TC & DeFlaun MF (2004). Application of a vital fluorescent staining method for simultaneous, near-real-time concentration monitoring of two bacterial strains in an Atlantic coastal plain aquifer in Oyster, Virginia. (pp. 1680-7). Vol. 70. Applied and environmental microbiology. Published, 05/01/2004.
  • Johnson WP & McIntosh WO (2003). Tracking of injected and resident (previously injected) bacterial cells in groundwater using ferrographic capture. (pp. 153-64). Vol. 54. Journal of microbiological methods. Published, 08/01/2003.
  • Johnson WP & McIntosh WO (2003). Tracking of injected and resident (previously injected) bacterial cells in groundwater using ferrographic capture. (pp. 153-64). Vol. 54. Journal of microbiological methods. Published, 08/01/2003.
  • Johnson WP, Bao G & John WW (2002). Specific UV absorbance of Aldrich humic acid: changes during transport in aquifer sediment. Environmental science & technology. Vol. 36, 608-16. Published, 08/01/2002.
  • Johnson WP, Bao G & John WW (2002). Specific UV absorbance of Aldrich humic acid: changes during transport in aquifer sediment. Environmental science & technology. Vol. 36, 608-16. Published, 08/01/2002.
  • DeFlaun MF, Fuller ME, Zhang P, Johnson WP, Mailloux BJ, Holben WE, Kovacik WP, Balkwill DL & Onstott TC (2002). Comparison of methods for monitoring bacterial transport in the subsurface. (pp. 219-31). Vol. 47. Journal of microbiological methods. Published, 04/01/2002.
  • DeFlaun MF, Fuller ME, Zhang P, Johnson WP, Mailloux BJ, Holben WE, Kovacik WP, Balkwill DL & Onstott TC (2002). Comparison of methods for monitoring bacterial transport in the subsurface. (pp. 219-31). Vol. 47. Journal of microbiological methods. Published, 04/01/2002.
  • Zhang BP, Johnson WP, Piana MJ, Fuller CC & Naftz DL (2002). Potential artifacts in interpretation of differential breakthrough of colloids and dissolved tracers in the context of transport in a zero-valent iron permeable reactive barrier. Ground water. Vol. 39, 831-40. Published, 02/01/2002.
  • Zhang BP, Johnson WP, Piana MJ, Fuller CC & Naftz DL (2002). Potential artifacts in interpretation of differential breakthrough of colloids and dissolved tracers in the context of transport in a zero-valent iron permeable reactive barrier. Ground water. Vol. 39, 831-40. Published, 02/01/2002.
  • Johnson WP, Zhang P, Gardner PM, Fuller ME & DeFlaun MF (2001). Evidence for detachment of indigenous bacteria from aquifer sediment in response to arrival of injected bacteria. Applied and environmental microbiology. Vol. 67, 4908-13. Published, 12/01/2001.
  • Johnson WP, Zhang P, Gardner PM, Fuller ME & DeFlaun MF (2001). Evidence for detachment of indigenous bacteria from aquifer sediment in response to arrival of injected bacteria. Applied and environmental microbiology. Vol. 67, 4908-13. Published, 12/01/2001.
  • Johnson WP, Zhang P, Fuller ME, Scheibe TD, Mailloux BJ, Onstott TC, Deflaun MF, Hubbard SS, Radtke J, Kovacik WP & Holben W (2001). Ferrographic tracking of bacterial transport in the field at the narrow channel focus area, Oyster, VA. (pp. 182-91). Vol. 35. Environmental science & technology. Published, 06/01/2001.
  • Johnson WP, Zhang P, Fuller ME, Scheibe TD, Mailloux BJ, Onstott TC, Deflaun MF, Hubbard SS, Radtke J, Kovacik WP & Holben W (2001). Ferrographic tracking of bacterial transport in the field at the narrow channel focus area, Oyster, VA. (pp. 182-91). Vol. 35. Environmental science & technology. Published, 06/01/2001.
  • Johnson WP (1996). Evaluation of the Pediatric Trauma Triage Checklist as a prehospital pediatric trauma triage tool for the state of Florida. (pp. 20-5; discussion 25-6). Vol. 11. Prehospital and disaster medicine. Published, 10/01/1996.