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Department: Civil, Environmental, and Architectural Engineering

Education: B.S., Princeton Univ. (1983), M.S., Ph.D., Massachusetts Institute of Technology (1988, 1992)
Teaching: CVEN 4424 Environmental Organic Chemistry, CVEN 5404 Water Chemistry, EVEN 1000 Introduction to Environmental Engineering
Research: Contaminant fate and transport in natural waters, surface and colloid chemistry, sources and transport of metals in watersheds affected by acid mine drainage

Office: SEEC S286B

Honors and Distinctions:

• “Best of the Best 2015”, Environmental Science & Technology Letters, for “A Framework for Identifying Organic Compounds of Concern in Hydraulic Fracturing Fluids Based on Their Mobility and Persistence in Groundwater” by J.D. Rogers, T.L. Burke, S.G. Osborn, and J.N. Ryan, 2015, Environmental Science & Technology Letters 2(6), 158-164, doi:10.1021/acs.estlett.5b00090.
• Distinguished Service Award, 2012, Association of Environmental Engineering and Science Professors.
• ��«����Ƶ County Pacesetter Award (Science/Health/Medicine), 2008, ��«����Ƶ Daily Camera
• National Notable Achievement Award, 2006, U.S. Environmental Protection Agency.

Recent Publications: 
** denotes work done in collaboration with graduate students
* denotes work done in collaboration with undergraduate students

• Miller K.D., Bentley M.J., Ryan J.N., Linden K.G., Larison C., Kienzle B.A., Katz L.E,, Wilson A.M., Cox J.T., Kurup P., Van Allsburg K.M., McCall J., Macknick J.E., Talmadge M.S., Miara A., Sitterley K.A., Evans A., Thirumaran K., Malhotra M., Garcia S., Stokes-Draut J.R., and Chellam S., 2021. Mine water use, treatment, and reuse in the United States: A look at current industry practices and select case studies. ACS Environmental Science & Technology Engineering, doi.org/10.1021/acsestengg.1c00244.
• DiGiulio D.C., Rossi R.J., Jaeger J.M., Shonkoff S.B.C., and Ryan J.N., 2021. Vulnerability of groundwater resources underlying unlined produced water ponds in the Tulare Basin of the San Joaquin Valley, California. Environmental Science & Technology, doi:10.1021/acs.est.1c02056.
• Lackey G., Rajaram H., Sherwood O.A., Ryan J.N., Bromhal G., and Dilmore R.M., 2021. Public data from three US states provides new insights into well integrity. Proceedings of the National Academy of Sciences 118(14), e2013894118; doi:10.1073/pnas.2013894118.
• Stanish L.F., Sherwood O.A., Lackey G., Osborn S.G., Robertson C.E., Harris J.K., Pace N., and Ryan J.N., 2020. Microbial and biogeochemical indicators of methane in groundwater aquifers of the Denver Basin, Colorado. Environmental Science & Technology; doi:10.1021/acs.est.0c04228.
• **Poulin B.A., Ryan J.N., Tate M.T., Krabbenhoft D.P., Hines M.E., Barkay T., Schaefer J., and Aiken G.R., 2019. Geochemical factors controlling dissolved elemental mercury and methylmercury formation in Alaskan wetlands of varying trophic state. Environmental Science & Technology 53(11), 6203-6213; doi:10.1021/acs.est.8b06041.
• **Rogers J.D., Thurman E.M., Ferrer I., Rosenblum J.S., Evans M.V., Mouser P.J., and Ryan J.N., 2019. Degradation of polyethylene glycols and polypropylene glycols in microcosms simulating a spill of produced water in shallow groundwater. Environmental Science: Processes and Impacts 21, 256-268; doi:10.1039/C8EM00291F.
• Entrekin S., Trainor A., Saiers J., Patterson L., Maloney K., Fargione J., Kiesecker J., Baruch-Mordo S., Konschnik K., Wiseman H., Nicot J.-P., and Ryan J.N., 2018. Water stress from high-volume hydraulic fracturing potentially threatens aquatic biodiversity and ecosystem services in Arkansas, U.S.A. Environmental Science & Technology 52(4), 2349–2358; doi:10.1021/acs.est.7b03304.
• Barrett P.M., Hull E.A., King C.E., Burkart K., **Ott K.A., Ryan J.N., Gawel J.E., and Neumann R.B., 2018. Increased exposure of plankton to arsenic in contaminated weakly-stratified lakes. Science of the Total Environment 625, 1606-1614; doi:10.1016/j.scitotenv.2017.12.336.
• **Poulin B.A., **Gerbig C.A., Kim C.S., Stegemeier J.P., Ryan J.N., and Aiken G.R., 2017. Effects of sulfide concentration and dissolved organic matter characteristics on the structure of nanocolloidal metacinnabar. Environmental Science & Technology 51(22), 13133-13142; doi:10.1021/acs.est.7b02687.
• **Rogers J.D., Ferrer I., Tummings S.S., Bielefeldt A.R., and Ryan J.N., 2017. Inhibition of biodegradation of hydraulic fracturing compounds by glutaraldehyde: Groundwater column and microcosm experiments. Environmental Science & Technology 51(17), 10251-10261.
• Rosenblum J., Nelson A.W., Ruyle B., Schultz M.K., Ryan J.N., and Linden K.G., 2017. Temporal characterization of flowback and produced water quality from a hydraulically fractured oil and gas well. Science of the Total Environment 596-597, 369-377.
• **Poulin B.A., Ryan J.N., Nagy K.L., Stubbins A., Dittmar T., Orem W., Krabbenhoft D.P., and Aiken G.R., 2017. Spatial dependence of reduced sulfur in Everglades dissolved organic matter controlled by sulfate enrichment. Environmental Science & Technology 51(7), 3630-3639.
• Lackey G., Rajaram H., Sherwood O.A., Burke T.L., and Ryan J.N., 2017. Surface casing pressure as an indicator of well integrity loss and stray gas migration in the Wattenberg Field, Colorado. Environmental Science & Technology 51(6), 3567-3574.
• Maloney K.O., Baruch-Mordo S., Patterson L.A., Nicot J.-P., Entrekin S.A., Fargione J.E., Kiesecker J.M., Konschnik K.E., Ryan J.N., Trainor A.M., Saiers J.E., and Wiseman H.J., 2017. Unconventional oil and gas spills: materials, volumes and risks to surface waters in four states of the U.S. Science of the Total Environment 581-582, 369-377.
• Sherwood O.A., **Rogers J.D., Lackey G., Burke T.L., Osborn S.G., and Ryan J.N., 2016. Groundwater methane in relation to oil and gas development and shallow coal seams in the Denver-Julesburg Basin of Colorado. Proceedings of the National Academy of Sciences 113(30), 8391-8396.
• Oikonomou P.D., Kallenberger J.A., Waskom R.M., Boone K.K., Plombon B.N., and Ryan J.N., 2016. Water acquisition and use during unconventional oil and gas development and the existing data challenges: Weld and Garfield Counties, CO. Journal of Environmental Management 181, 36-47.
• Thurman E.M., Ferrer I., Rosenblum J., Linden K., and Ryan J.N., 2016. Identification of polypropylene glycols and polyethylene glycol carboxylates in wastewater from hydraulic fracturing. Journal of Hazardous Materials 323, Part A, 11-17.
• **Mohanty S.K., Saiers J.E., and Ryan J.N., 2016. Colloid mobilization in a fractured soil: Effect of pore water exchange between preferential flow paths and soil matrix. Environmental Science & Technology 50(5), 2310-2317.
• **Webster J.P., Kane T.J., Obrist D., Ryan J.N., and Aiken G.R., 2016. Estimating mercury emissions resulting from wildfire in the western United States. Science of the Total Environment 568, 578-586.