Robert N. Stewart

Robert N. Stewart

Scientist

Phone: (865) 241-0596
Fax: (865) 241-6261
Email: stewartr1@ornl.gov

Education

Ph.D. Geography, 2011, University of Tennessee
M.S. Mathematics, 1994, University of Tennessee
B.S. Mathematics and Statistics, 1992, University of Tennessee

Research Interests

Research is focused on quantitative, computational methods particularly in the areas of geospatial and spatiotemporal modeling, with an emphasis on uncertainty, risk, and decision analysis. Areas of application include population dynamics, demography, environmental pollution and regulatory compliance. Quantifying uncertainty and risk as well as understanding the implications of both for decision making is a recurring theme in the work.

Professional Experience

Oak Ridge National Laboratory (2009-present)
Research is typically computational in nature with a focus on population dynamics, small area estimation, spatial and spatiotemporal analytics, uncertainty analysis, risk, and decision support.

University of Tennessee Joint Faculty Assistant Professor of Geography (2011-present)
Focus is on proposal development, teaching when needed, and leading the Spatial Analysis and Decision Assistance (SADA) program. SADA is an internationally recognized windows freeware program designed for applications in environmental spatial data analysis and associated risk assessment. SADA includes an integrated mix of data management, visualization, geospatial analysis, GIS, risk assessment, cost/benefit analysis, and sampling optimization routines. Educational activities included teaching workshops and short courses focused on SADA both at the university and abroad.  Research and development activities are closely connected with The Institute for Environmental Modeling, a multidisciplinary research institute at the University.

University of Tennessee Senior Research Associate (1994-2010)
Activities included serving as principle investigator, technical lead, and in most cases point of contact with sponsoring agencies such as the Environmental Protection Agency, the Nuclear Regulatory Commission, the Department of Energy, and the Oak Ridge National Laboratory. Effort centered largely on management and development of the Spatial Analysis and Decision Assistance (SADA) software program.

Professional Affiliations

  • The Society for Risk Analysis
  • Association of American Geographers
  • International Society for Bayesian Analysis
  • International Association for Mathematical Geosciences

Reviewer

  • Risk Analysis
  • Mathematical Geosciences
  • Environmental Modelling and Software
  • Stochastic Environmental Research and Risk Assessment

Peer Reviewed Publications

Stewart, R.N. 2012. A Subsurface Decision Model for Supporting Environmental Compliance, NUREG/CR-7021. Washington, D.C., United States Nuclear Regulatory Commission.

Stewart, R.N. 2011. A Geospatial Based Decision Framework for Extending MARSSIM Regulatory Principles into the Subsurface. Doctoral Dissertation, Department of Geography at the University of Tennessee.

Stewart, R.N. and S.T. Purucker. 2011. "An environmental decision support system for spatial assessment and selective remediation." Environmental Modelling & Software 26(6): 751-760.

Purucker, S.T., Stewart, R.N., Wulff, J. 2010. A spatial decision support system for efficient environmental assessment and remediation. In Madden, M., Allen, E., (Eds.). Landscape Analysis Using Geospatial Tools, Springer-Verlag. (Available 9/2011)

Purucker, S. T., R. N. Stewart, and C. J. Welsh. 2009. SADA: Ecological Risk Based Decision Support System for Selective Remediation. Chapter 11, A. Marcomini, G.W. Suter, and A. Critto (ed.), Decision Support Systems for Risk Based Management of Contaminated Sites. Springer Science + Business Media, LLC, New York, NY, pgs. 239-256.

Mahmoud, M., Liu, Y., Hartmann, H., Stewart, S., Wagener, T., Semmens, D., Stewart, R.N., Gupta, H.V., Dominguez, D., Dominguez, F., Hulse, D., Letcher, R., Rashleigh, B.,  Smith, C., Street, R., Ticehurst, J., Twery, M., Delden, H. van, Waldick, R., White, D., Winter, L. (2009). "A Formal Framework for Scenario Development to Support Environmental Decision Making". Environmental Modelling & Software. 24(7): 798-808.

Liu, Y., M. Mahmoud, H. Hartmann, S. Stewart, T. Wagener, D. Semmens, R.N. Stewart, H. Gupta, D. Dominguez, D. Hulse, R. Letcher, B. Rashleigh, C. Smith, R. Street, J. Ticehurst, M. Twery, H. van Delden, R. Waldick, D. White, and L. Winter., 2008, Formal scenario development for environmental impact assessment studies, In State of the Art and New Perspectives  in Environmental Modelling and Software, edited by Jakeman, A., A. Voinov, A. E. Rizzoli, and S. Chen, Elsevier. Volume 3: 145-162.

Voinov, A., Hood, R., Daues, J., Assaf, H., Stewart, R.N., “Building a Community Modelling and Information Sharing Culture” In State of the Art and New Perspectives  in Environmental Modelling and Software, edited by Jakeman, A., A. Voinov, A. E. Rizzoli, and S. Chen, Elsevier. Volume 3: 345-366.

Modis, K., Yu, H-L, G. Christakos, R.N. Stewart and G. Papantonopoulos, 2007.  “BME-generated temperature maps of the Nea Kessani geothermal field”, Invited chapter, In Geothermal Energy Research Frontiers, Columbus, F. (ed.), Nova Science Publ., Inc., Hauppauge, NY, In Press.

Purucker, S.T., Welsh, C.J.E., Stewart, R.N., Starzec, P. 2007.  Use of habitat-contamination spatial correlation to determine when to perform a spatially explicit ecological risk assessment.  Ecological Modelling, 204(1-2):180-192 (nominated for an EPA 2010 Level II Scientific and Technological Achievement Award).

Lyon, B.F., Purucker, S.T., Stewart, R.N., 1994. The Value of Perfect Information: How Much is a Crystal Ball Worth?  Proceedings of the International Specialty Conference. Cost Effective Acquisition and Utilization of Data in the Management of Hazardous Waste Sites. Air & Waste Management Association. Pittsburgh, PA. CONF-940386-2:44-55.

Presentations

  • Stewart, R.N. and Urban, M., and Morton, A. 2012. Population Density Tables: Incorporating socio-cultural dynamics in estimating small area populations at risk, Society for Risk Analysis Annual Meeting, San Francisco, CA.
  • Stewart, R.N. and Urban, M, 2012. Eliciting and Transforming Population Density Knowledge into a Bayesian Prior Probability Distribution, Association Of American Geographers Annual Meeting, New York, NY.
  • Conley, J. and Stewart, R.N, 2011. Using Fine Resolution Population Data and Spatial Interaction Modeling to
    Estimate Risk from Airborne Toxic Releases, The 11th International Conference of Geocomputation, London.
  • Urban, M., Bright, E., Stewart, R.N., Lee, R., and Sylvester, L., 2011 Creating a Database for Demographic and Socio-cultural Characteristics, Association of American Geographers Annual Meeting, Seattle, WA.
  • Stewart, R.N., 2010. A Geostatistically Informed Environmental Sampling Design for Improving Boundary Delineation of Contaminated Areas, Association of American Geographers Annual Meeting, Washington D.C.
  • Stewart, R.N., 2009. Spatial Analysis and Decision Assistance Version 5 Overview, Midwestern States Risk Assessment Symposium, Indianapolis, IN.
  • Stewart, R.N., 2009.  Spatial Analysis and Decision Assistance (SADA): An integration of spatial analysis, risk, sample design, and GIS, Interagency Steering Committee on Multimedia Environmental Models Public Workshop, Rockville, MD.
  • Purucker, S.T., Stewart, R.N., Dolislager, F., 2007.  Human health and ecological risk assessment with Spatial Analysis and Decision Assistance (SADA) Freeware.  Office of Solid Waste and Emergency Response, Technology Innovation Program, CLU-IN Studio Internet Seminar (presentation).
  • Stewart, R.N.., Purucker, S.T., Powers, G.E., 2007.  SADA: A Freeware Decision Support Tool Integrating GIS, Sample design, Spatial Modeling, and Risk Assessment.  Proceedings of the International Symposium on Environmental Software Systems, Prague, Czech Republic.
  • Stewart, R.N., 2007, Purucker, S.T., 2007.  SADA: A freeware decision support tool integrating GIS, sample design, spatial modeling, and environmental risk assessment.  233rd American Chemical Society National Meeting, Chicago, IL.
  • Stewart, R.N., 2006. SADA: A Freeware Decision Support Tool Integrating GIS, Sample design, Spatial Modeling, and Risk Assessment, Graduate Seminar, Department of Geography, UTK, Knoxville, TN.
  • Stewart, R.N., 2006. SADA: A Freeware Decision Support Tool Integrating GIS, Sample design, Spatial Modeling, and Risk Assessment, East Tennessee Geographic Information Systems Conference, October, 2006.
  • Stewart, R.N., 2006. SADA: A Freeware Decision Support Tool Integrating GIS, Sample design, Spatial Modeling, and Radiological Assessment, Health Physics Society Midyear, Knoxville, TN.
  • Stewart, R.N.., Purucker, S.T., 2006.  SADA: A Freeware Decision Support Tool Integrating GIS, Sample design, Spatial Modeling, and Risk Assessment.  Proceedings of the Third Biennial Meeting of the International Environmental Modelling and Software Society, Burlington, Vermont.
  • Stewart, R.N., Purucker S.T. 2004. Incorporating Secondary Information Into Environmental Sampling Designs. Joint Proceedings of the Sixth International Symposium on Spatial Accuracy Assessment in Natural Resources and Environmental Sciences and the 15th Annual Conference of the International Environmetrics Society.
  • Stewart, R.N., Purucker S.T., Powers, G.E, 2005. Spatial Approaches for Subsurface Sample Design, Characterization, and Decision Support, Proceedings of the ANS Topical Meeting on Decommissioning, Decontamination, & Reutilization, Denver, Colorado.
  • Stewart, R.N., Purucker, S.T. 2003. Geospatially-Based Secondary Sample Designs, Society for Risk Analysis World Congress on Risk, Belgium.
  • Stewart, R.N., Purucker, S.T. 2003. Geospatially-Based Secondary Sample Designs, Society for Risk Analysis World Congress on Risk, Belgium.
  • Purucker, S.T., Stewart, R.N., Welsh, C.J.E., 2003. Secondary Sample Designs for Risk Assessment. Society for Risk Analysis; Baltimore, Maryland, (poster).
  • Stewart, R.N., Purucker, S.T., 2003. Initial Sample Designs for Risk Assessment. Society for Risk Analysis; Baltimore, Maryland, (poster).
  • Purucker, S.T., Stewart, R.N., 2002.  SADA: Freeware to Assist in Integrating Ecological and Human Health Risk Assessment with Geostatistical Analyses. Society for Risk Analysis; New Orleans, Louisiana, (poster).
  • Stewart, R.N., Purucker, S.T., Dolislager, F.G., Clauberg, M., 2001.  Spatial Analysis and Decision Assistance (SADA): Incorporation of Geospatial Statistical Analysis into Risk Assessment Based Decision Making.  Society for Risk Analysis; Seattle, Washington, (poster).
  • Stewart, R.N., 2001 Spatial Analysis and Decision Assistance Overview Opening remarks at the annual EPA FIELDS/SADA Conference, Denver, Colorado, 2001.
  • Stewart, R.N., 2000. Geostatistically Based Sampling Strategies, FIELDS/SADA 2000 Annual EPA Conference, Chicago Illinois.
  • Stewart, R.N. Purucker, S.T. 2000. Geospatial Decision Frameworks for Remedial Design and Secondary Sampling NATO/CCMS Special Session on Decision Support Tools Number 245. EPA 542-R-01-002.
  • Stewart, R.N., 1998. Geostatistics in Environmental Decision Making, A presentation given to the National Institute for Environmental Renewal in Pennsylvania covering the contribution of spatial statistics in providing a clear and defensible decision framework.
  • Lyon, B.F., Purucker, S.T., Stewart, R.N., 1994. The Value of Perfect Information: How Much is a Crystal Ball Worth? Proceedings of the International Specialty Conference. Cost Effective Acquisition and Utilization of Data in the Management of Hazardous Waste Sites. Air & Waste Management Association. Pittsburgh, PA. CONF-940386-2:44-55.

Reports

  • Norrman, J., Purucker, S.T., Back, P.-E., Engelke, F., Stewart, R.N., 2009. Metodik för statistik utvärdering av miljötekniska undersökningar I jord (Method for statistical evaluation of environmental soil investigations). Naturvårdsverket (Swedish Environmental Protection Agency), Rapport 5932. ISBN 978-91-620-5932-3.
  • Norman, J., Purucker, S.T., Stewart, R.N., Back, P.-E., Englelke, F., 2008. Framework for optimizing the evaluation of data from contaminated soil in Sweden. Conference proceedings of ConSoil 2008, 10th International Conference on Soil-Water Systems; Milan, Italy.
  • Starzec, P., Purucker, S.T., Stewart, R.N.., 2006. Kvantifiering och presentation av osäkerheter i riskbedömning och beslutsprocess: exemplifiering med fallstudier. Rapportutkast (Swedish).
  • Stewart, R.N. and Gogolak, C. 2003. Viable Geobayesian Approach for Supporting and Characterizing 2d and 3d Sampling Designs, US Nuclear Regulatory Commission Letter Report, April 2003.
  • Stewart, R.N., 2002. Evaluation of Terminated Licenses Parts 30, 40, and 70: The Terminated License Tracking System, NUREG/CR-6669, United States Nuclear Regulatory Commission, Office of Nuclear Material Safety and Safeguards.
  • Stewart, R.N. 2001. Test and Evaluation of the Proof-of-Concept Version of SADA Incorporating Bayesian Geostatistics, US Nuclear Regulatory Commission Letter Report.
  • Stewart, R.N., Purucker, S.T., Lyon, B.F., 1995. Geostatistical Applications in Environmental Remediation. ES/ER/TM 146.
  • Douthat, D., Stewart, R.N., Armstrong, A.Q., 1995. Fixed Capital Investments for the Uranium Soils Integrated Demonstration Soils Treatment Technologies, prepared for the Office of Technology Development at DOE.
  • Douthat, D., Stewart, R.N., Armstrong, A.Q., 1995. Cost Results from the 1994 Fernald Characterization Field Demonstration for Uranium-Contaminated Soils, prepared for the Office of Technology Development at DOE.
  • Douthat, D., Stewart, R.N., Armstrong, A.Q, 1995. Operating and Life-Cycle Costs for Uranium-Contaminated Soil Treatment Technologies, prepared for the Office of Technology Development.
  • Stewart, R.N., Armstrong, A.Q., James, B.R., Douthat, D.M., Purucker, S.T., 1995. Cost Versus Risk Reduction in Remedial Action: A Decision Framework. ORNL/TM 13143.
  • Purucker, S.T., Lyon, B.F., Nanstad, L.D., Stewart, R.N., 1994. Decision Support for CERCLA Investigations: An Introduction to Decision Analysis Applications. ES/ER/TM-134.

Teaching/Mentoring

  • ITRC ARAMS/SADA Conference October, 2008. Kennebunkport, ME, SADA Training
  • USEPA, TRIAD Conference June 10th-12th, 2008 in Amherst, MA. SADA Training.
  • State of Illinois, Department of Natural Resources May 21-22nd, 2008. SADA Training.
  • University of Tennessee SADA Training, Knoxville, TN, April 23rd-25th, 2008. SADA Training.
  • NMA Uranium Recover Workshop, Denver, May 17th, 2007.
  • University of Helsinki, “Overview of Environmental Methods in SADA”, Helsinki, May 2007.
  • Uranium Recovery Workshop, SADA training, Denver CO, May 2007.
  • University of Tennessee, “Environmental Assessment Methods Using SADA”, Knoxville, TN, April, 2007.
  • Stewart, R.N., Purucker, S.T., 2006.  Uses of Spatial Analysis and Decision Assistance.  Office of Solid Waste and Emergency Response, Technology Innovation Program, CLU-IN Studio Internet Seminar.
  • University of Tennessee, “Environmental Assessment Methods Using SADA”, Knoxville, TN, 25-27 October 2006.
  • Swedish Geotechnical Institute Training, Goteborg, Sweden, 10-12 May 2006. SADA Training.
  • University of Tennessee, “Environmental Assessment Methods Using SADA”, Knoxville, TN, 26-28 April 2006.
  • University of Tennessee, “Environmental Assessment Methods Using SADA”, Knoxville, TN, 5-7 October 2005.
  • Swedish Geotechnical Institute, Goteborg, Sweden, 12-15 September 2005. SADA Training.
  • US Nuclear Regulatory Commission SADA Training, Rockville, MD, 12-14 April 2005.
  • US Naval Facilities Engineering Command (NAVFAC) SADA Workshop, Philadelphia, Pennsylvania, 2-3 August 2005.
  • University of Tennessee, “Environmental Assessment Methods Using SADA”, Knoxville, TN, 23-25 February 2005.
  • Petróleo Brasileiro SA (Petrobras), Rio de Janeiro, Brazil,16-20 Aug 2004.
  • NRC SADA Workshop, Rockville, MD, 4-5 May 2004.
  • FIELDS/SADA 2003 Training Conference in Chicago, 5-7 March 2003.
  • EPA Ecological Risk Assessment Forum, National Conservation Training Center, Shepherdstown, West Virginia, 9 January 2002.
  • EPA Region 9, San Francisco, California, 28-29 August 2001.
  • Geospatial Methods For Environmental Decision Making and Cost Benefit Analysis, Fifth Course on Mathematical Ecology at The Abdus Salam International Centre for Theoretical Physics, Trieste, Italy, 2000.

Grants & Contracts

  • National Geospatial-Intelligence Agency, (266), “Multi-Disciplinary GEOINT Analysis”, $510k, 3/2012-3/2013, (co-investigator)
  • Nuclear Regulatory Commission/ORNL, (F1163), “Terminated License and Complex Site Tracking Systems”, $940k, 10/2010-9/2015 (technical lead)    
  • Nuclear Regulatory Commission/ORNL, (F1038), “Complex Sites Tracking System”, $991k, 11/2005-0/2010, (technical lead)
  • Nuclear Regulatory Commission (NRC-06-066), "Sparse Radiological Subsurface Survey Data Analysis", 3/2006-2/10/2010, $980K, (PI)
  • Nuclear Regulatory Commission (NRC-04-02-057), "Bayesian subsurface radiological surveying and analysis", 9/2002-9/2005, $948K (PI)
  • Swedish EPA/Swedish Geotechnical Institute, Spatial Risk Considerations, $10K, 10/05-1/06 (participant)
  • Navy/TetraTech, US Naval Facilities Engineering Command (NAVFAC) SADA Applications Workshop (R01-1086-115), $10K, 4/05-8/05 (co-PI)
  • US Department of Transportation/Research and Special Program Administration/Volpe Center, EPA Region 5 FIELDS Technical Support (R01-1086-111), $50K, 10/04-4/05 (PI)
  • US Department of Transportation/ Research and Special Program Administration /Volpe Center, EPA Region 5 FIELDS Technical Support (R01-1086-090), $50K, 1/04-7/04 (PI)
  • US EPA Region 5 Superfund Division Innovative Technology Evaluation (R01-3515-066), $200K, 10/02-7/03 (co-PI)
  • US EPA Region 5 Superfund Division Innovative Technology Evaluation (R01-3515-066), $200K, 10/01-9/02 (co-PI)
  • US EPA Region 5 Superfund Division Innovative Technology Evaluation (R01-3515-066), $100K, 4/01-9/01 (co-PI)
  • US EPA Region 5 Water Division, SADA/FIELDS Technology Development (R01-3515-066), $65K, 9/00-2/01 (co-PI)
  • US EPA Region 5 Water Division, SADA/FIELDS Technology Development (R01-3515-066), $50K, 7/00-12/00 (co-PI)
  • US EPA R5 Water Division, SADA/FIELDS Technology Development (R01-3515-066), $70K, 2/00-9/00 (co-PI)
  • US EPA Office of Research and Development National Center for Environmental Research and Quality Assurance, SADA/FIELDS Development- Technology Innovation Office, $50K, 10/99-7/00 (co-PI)

Awards, Honors, and Certifications

  • Publication nominated for an EPA 2010 Level II Scientific and Technological Achievement Award (http://www.epa.gov/ncer/staa/annual/2010/2010level2.html)
    • Use of Habitat-Contamination Spatial Correlation to Determine when to Perform a Spatially Explicit Ecological Risk Assessment Ecological Modelling, 204(1-2):180-192.
  • Publication nominated for an EPA 2010 Level II Scientific and Technological Achievement Award. (http://www.epa.gov/ncer/staa/annual/2010/2010level2.html)
    • SADA: Ecological Risk Based Decision Support System for Selective Remediation Decision Support Systeme for Risk-Based Management of Contaminated Sites, Springer Science + Business Media, LLC, New York, NY, pgs 239-256.
  • Invited Speaker, Association of American Geographers Annual Meeting, Washington D.C., A Geostatistically Informed Environmental Sampling Design for Improving Boundary Delineation of Contaminated Areas, 2010.
  • Invited Speaker, Midwestern States Risk Assessment Symposium, Indianapolis, IN, Spatial Analysis and Decision Assistance Version 5 Overview, 2009.
  • Invited Speaker, Interagency Steering Committee on Multimedia Environmental Models Public Workshop, Rockville, MD, Spatial Analysis and Decision Assistance (SADA): An integration of spatial analysis, risk, sample design, and GIS, 2009.
  • Invited member, Interagency Steering Committee on Multimedia Environmental Models, working group 2, 2008.
  • Invited Speaker, Health Physics Society Midyear, Knoxville, TN. SADA: A Freeware Decision Support Tool Integrating GIS, Sample design, Spatial Modeling, and Radiological Assessment, 2006
  • Invited Speaker, ANS Topical Meeting on Decommissioning, Decontamination, & Reutilization, Denver, Colorado, Spatial Approaches for Subsurface Sample Design, Characterization, and Decision Support,2005
  • Invited Speaker, Society for Risk Analysis World Congress on Risk, Brussels, Belgium,  Geospatially-Based Secondary Sample Designs, 2003
  • Invited Speaker, EPA FIELDS/SADA Conference, Denver, Colorado, Opening remarks, 2001.
  • Invited Speaker, NATO/CCMS Special Session on Decision Support Tools, Wiespaden, Germany, Geospatial Decision Frameworks for Remedial Design and Secondary Sampling, 2000
  • Invited Speaker, Geostatistically Based Sampling Strategies, FIELDS/SADA Annual EPA Conference, Chicago Illinois, 2000
  • Invited Lecturer, Fifth Course on Mathematical Ecology at The Abdus Salam International Centre for Theoretical Physics, Trieste, Italy, Geospatial Methods For Environmental Decision Making and Cost Benefit Analysis, 2000.

Copyrights  

Spatial Analysis and Decision Assistance is a windows freeware program for integrating risk analysis, geospatial analysis, cost, statistics, visualization, and a variety of frameworks including secondary sampling schemes into a single package. Copyright is through the University of Tennessee Research Corporation from 1995-present.

The Population Markup Language specification provides an XML schema for storage and communication of spatiotemporal population data. Copyright is through the Oak Ridge National Laboratory from 2011-present.

Contact Information

Phone: (865)-574-7646
Email:   stewartrn@ornl.gov / stewart@utk.edu
Web page:  http://www.ornl.gov/sci/gist/index.shtmlhttp://web.utk.edu/~stewart/