John Villinski, Ph.D.
Hydrologist
Expertise
Mr. Villinski, a senior hydrologist, joined Hydro Geo Chem in 2008. He has worked in both field and laboratory capacities. His field work has focused on natural riparian areas in Arizona, focusing on remediation of metals contamination as well as the effects of nutrient cycling on the health of the system. Laboratory studies have focused on redox-sensitive systems related to acid mine drainage/solid surface interactions and nutrient cycling in northeastern forests impacted by nitrate deposition. He has also modeled the transport of metals in column experiments and the kinetics of redox reactions in acid mine drainage systems and sulfur dioxide oxidation in snow packs.
Education
-Ph.D. (Hydrology) University of Arizona, 2001
-B.S. (Hydrology) University of Arizona, 1991
Academic Honors
Association of Environmental Engineering and Science Professors, 2000
Student Award for Best Presentation at the James J. Morgan
Symposium, 220th American Chemical Society National Meeting
John and Margaret Harshbarger Memorial Fellowship, 1996 - 1997
DOE Environmental Restoration/Waste Management Fellowship, 1992 – 1996
Affiliations
American Geophysical Union
American Chemical Society
Arizona Hydrologic Society
International XAFS Society
Representative
Experience
• Designed and executed projects to investigate the redox reactions between iron, nitrogen, and organic carbon to gain a better understanding of the abiotic controls of nitrogen speciation in northeastern forest soils impacted by chronic nitrogen deposition. Wrote project summary reports and technical papers.
• Designed, coordinated, and implemented field and laboratory methods to investigate linkages between hydrology and nutrient cycles in semiarid riparian systems in the San Pedro River and Rio Grande basins. Formulated budgets for research projects; structured, coordinated, and wrote project summary reports; coordinated and assisted in leading group meetings; provided planning and intellectual support for graduate student projects; trained students on analytical equipment.
• Designed and executed project to investigate the mineral-aqueous interface geochemistry in an alluvial aquifer contaminated by acid mine drainage. Developed a novel flow-through reactor cell and designed protocol for in-situ, real-time geochemical measurements used at the Stanford Synchrotron Radiation Laboratory, Menlo Park, CA. Modeled geochemical redox kinetics and metal transport in saturated columns in presence of humic substances.
• Designed and executed a project to investigate the effects of natural organic matter on the reductive dissolution of pyrolusite by Fe (II) in anaerobic conditions.
• Designed, organized, and led tracer-injection experiments in both stream and gravel bars to investigate the retention and transformation of nutrients, and to relate those changes to hydrologic flow paths. Helped design and organize the installation of seven novel scour sensors to provide continuous real-time measurements of head and sediment depth, which enabled the quantification of the role of episodic flow events on microbial activity, a proxy of the health of the riparian system. Collected and analyzed data for major anions, pH, DO, organic carbon, tracer concentrations, and nitrogen speciation.
• Responsible for investigating redox reactions between iron, carbon and nitrogen to understand abiotic controls on nitrogen speciation in northeastern forest soils impacted by chronic nitrogen deposition. Designed and performed anoxic batch-titration experiments; analyzed samples for iron, nitrogen, and carbon species. Analyzed and modeled kinetic reaction data.
• Responsible for co-initiated synoptic sampling of the Rio Grande to investigate the temporal and spatial variability of nutrients. Responsible for filtering and analyzing samples for nitrogen species and organic carbon.
• Responsible for designing and performing anoxic batch-titration and column experiments to investigate the redox reactions between iron and manganese species. Collected samples and analyzed them for manganese and iron species concentrations. Designed and implemented a new column to be used at the Stanford Synchrotron Research Laboratory; this column allowed for collection of in-situ, real-time data that was analyzed for aqueous and solid iron and manganese species. Developed a novel procedure for quantitatively separating the various manganese species signals from the overall spectra. Modeled the kinetics of the redox reaction.
• Responsible for designing and performing column experiments investigating the biotically mediated oxidation of aqueous manganese. The experiments were performed at the Stanford Synchrotron Research Laboratory to collect real-time, in-situ data of the manganese speciation during the reaction.
• Assisted in the design of field experiments, including Br-stream tracer studies to determine the extent of the hyporheic zone and the storage capacity of the vegetative zone. Determined diel cycles of chemical constituents within the free-flowing stream, hyporheic and vegetative zones, and shallow groundwater. Collected samples for Br- stream tracer studies in stream, groundwater, surface water, and hyporheic zone for chemical analysis. Installed piezometers, shallow ground-water drive points, and mini-point sampler.
• Modeled the transport of aqueous copper in column experiments. This project investigated the effects of dissolved organic matter, clay, and sand on the transport of Cu2+ in groundwater systems through the use of model components in laboratory column and batch experiments. The modeling was performed with HYTEQ, a transport code with equilibrium speciation.
• Modeled dry deposition of SO2 to snow packs with subsequent oxidation of SO2 to SO4-2. Processed snow samples from laboratory column experiments on the ion chromatograph and the atomic absorption spectrophotometer for inorganic anion and cation concentrations, respectively.
PUBLICATIONS:
Villinski, J.E., J.E. Saiers, and M.H. Conklin. 2003. The Effects of Reaction-Product Formation on the Reductive Dissolution of MnO2 by Fe (II), Environmental Science & Technology, 37, pp. 5589-5596, 2003.
Conklin, M., J. Villinski, and J. Kay. 2001. Geochemistry of acid mine contamination-aquifer interactions, International Journal of Occupational Medicine and Environmental Health, 14, pp. 249-259, 2001.
Villinski, J.E., P.A. O'Day, and T.L. Corley. 2001. Conklin, M.H., A flow-through cell for coupling spectroscopic data with solution chemistry of geochemical reaction, Environmental Science and Technology, 35, pp. 1157-1163, 2001.
Bargar, J.R., B.M. Tebo, and J.E. Villinski. 2000. In situ characterization of Mn (II) oxidation by spores of the marine Bacillus sp. strain SG-1, Geochimica et Cosmochimica Acta, 64, No. 16, pp. 2775-2778, 2000.
Bargar, J.R., B.M. Tebo, K.H. Pecher, V. Chiu, and J.E. Villinski. 2000. Tonner, B.P., Kinetics and products of Mn oxide biomineralization by spores of the marine Bacillus, sp. strain SG-1, extended abstract, Proceedings of the 220th American Chemical Society Meeting, August 20-25, 2000, Washington, DC, pp. 491-493.
Villinski, J.E., P.A. O'Day, J.R. Bargar, and M.H. Conklin. 2000. Reductive dissolution of MnO2 by Fe (II): Effects of chemical gradients and intermediate phase structural information, extended abstract, Proceedings of the 220th American Chemical Society Meeting, August 20-25, 2000, Washington, DC, pp. 630-633.
Bargar, J.R., B.M. Tebo, and J.E. Villinski. 1999. Mechanisms of microbially mediated and abiotic Mn transformations in aquatic environments, in 1998 SSRL Activity Report, Stanford University, pp. 7-378 to 7-382, 1999.
Villinski, J.E., P.A. O'Day, T.L. Corley, and M.H. Conklin. 1999. A flow-through cell for in situ, real-time X-ray absorption spectroscopy studies of geochemical reactions, in Morganwalp, D.W. and Buxton, H.T., Eds., U. Geological Survey Toxic Substances Hydrology Program - Proceedings of the Technical Meeting, Charleston, South Carolina, March 8‑12, 1999 - Volume 1, Contamination from Hard Rock Mining; U. Geological Survey Water‑Resources Investigations Report 99-4018A, pp. 217-225.
O'Day, P., S. Carroll, G. Waychunas, M. Ebert, N. Sahai, J. Villinski, L. Garvie, K. Savage, and D. Bird. 1998. Coordination and bonding of metal ions in natural soils and sediments using XAS, in 1997 SSRL Activity Report, Stanford University, pp. 7-174 to 7-177, 1998.
Conklin, M.H., R.A. Sommerfeld, K. Laird, and J.E. Villinski. 1993. Sulphur dioxide reactions on ice surfaces: Implications for dry deposition to snow, Atmospheric Environment, 27A, pp. 159-167, 1993.
INVITED TALKS AND PRESENTATIONS:
Villinski, J. E., J. Chorover, D.B. Dail, and E.A. Davidson. 2004. The Effects of Catechol Concentration on the Redox Chemistry of Sulfate Green Rust and Nitrate, Annual Meetings of the Soil Science Society of America, Seattle, WA, October 31 - November 4, 2004
P. Brooks, J. Hogan, J. Schade, J. Villinski, M. Lemon, A. Huth, P. Haas, and M. Conklin. 2003. Scaling biogeochemical processes along rivers in semiarid regions: how do point-scale processes relate to water quality at larger scales? A talk presented at the EGS-AGU Spring Meeting in Nice, France, 2003.
Lemon, M.M., P.D. Brooks, A.K. Huth, and J.E. Villinski. 2002. Spatial and Temporal Variability in Dissolved Organic Matter (DOM) Concentrations Along a 90km Reach of the San Pedro River, AZ., Eos Trans. AGU 83 (47), Fall Meeting Suppl., Abstract H21A-0974, 2002.
Schade, J.D., D.B. Lewis, A.K. Huth, J. Villinski, M. Conklin, N.B. Grimm, and J. Hamblen. 2002. Nutrient dynamics in subsurface flowpaths of an arid watershed, North American Benthological Society Annual Meeting, Pittsburgh, PA, 2002.
Schade, J.D., N.B. Grimm, D.B. Lewis, J.E. Villinski, J.R. Welter, M. Conklin, and A.K. Huth. 2002. Understanding Riparian Ecosystem Function: Linking Biogeochemistry and Hydrology at Multiple Scales, Eos Trans. AGU 83 (47), Fall Meeting Suppl., Abstract H11F-08, 2002.
Villinski, J.E., J.F. Hogan, P.D. Brooks, P.A. Haas, and S.K. Mills. 2002. Temporal and spatial variability of nitrogen species and organic carbon in the Rio Grande, Eos Trans. AGU 83 (47), Fall Meeting Suppl., Abstract H11F-10, 2002.
Villinski, J.E., P.A. O'Day, and M.H. Conklin. 2001. In situ formation and transformation of Fe (III) precipitates from the reductive dissolution of MnO2 by Fe (II), 222nd American Chemical Society National Meeting, Chicago, IL, 2001.
Bargar, J.R., B.M. Tebo, K.H. Pecher, V. Chiu, J.E. Villinski, and B.P. Tonner. 2000. Kinetics and products of Mn oxide biomineralization by spores of the marine Bacillus, sp. strain SG-1, 220th American Chemical Society National Meeting, Washington, D.C., 2000.
Villinski, J.E., P.A. O'Day, J.R. Bargar, and M.H. Conklin. 2000. Reductive dissolution of MnO2 by Fe (II): Effects of chemical gradients and intermediate phase structural information, 220th American Chemical Society National Meeting, Washington, D.C., 2000.
Tebo, B.M., J.R. Bargar, and J.E. Villinski. 1998. Mechanisms and products of bacterial Mn (II) oxidation: An X-ray absorption spectroscopy study, The XIVth International Symposium on Environmental Biogeochemistry, September 26-30, Huntsville, Ontario, Canada, 1999.
Villinski, J.E., P.A. O'Day, and M.H. Conklin. 1998. Reductive dissolution of pyrolusite by Fe (II): A real-time in situ XANES experiment, EOS, 79, #45, p.342, 1998.
O'Day, P.; S. Carroll, M. Newville, C. Fuller, and J. Villinski. 1997. Techniques and applications of synchrotron XAS to metal bonding in contaminated sediments and soils, 214th American Chemical Society National Meeting, Las Vegas, NV, 1997.
Villinski, J.E., M.H. Conklin, and P.A. O'Day. 1997. Factors affecting the release of Mn from an anoxic, acidic, subsurface aquifer, Superfund Basic Research Program Conference, Durham, NC, February, 1997.
Villinski, J.E., M.H. Conklin, and L. Liang. 1995. Effect of natural organic matter on the Mn/Fe redox couple, 209th American Chemical Society National Meeting, Anaheim, CA, 1995.
Villinski, J.E., P.E. Mariner, and M.H. Conklin. 1994. Cu (II) transport in the presence of humic substances, EOS, 75, #44, p. 42, 1994.
Cao, Y., M.H. Conklin, J. Villinski, and E. Betterton. 1992. Competitive complexation of trace metals to dissolved humic acids, EOS, 73, #43, p. 216, 1992.
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