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Michael J. Barden
Vice President
Senior Hydrogeologist



Mike BardenMr. Barden, a senior hydrogeologist with over 20 years of environmental experience as a consultant and state regulator, joined Hydro Geo Chem, Inc. in December 2012. He has dealt extensively with hydrogeologic evaluation, contaminant transport and fate evaluation, and soil and groundwater modeling and has expertise in risk assessment and natural attenuation of organic and inorganic contaminants. His expertise also includes the use of groundwater, soil, and geochemical models to support decision-making for site characterization and remediation. His experience includes characterization, evaluation and review of soil and groundwater conditions and remedial designs for CERCLA, RCRA and UST sites and landfills involving chlorinated solvents, petroleum hydrocarbons and metals. Mr. Barden was formerly a senior hydrogeologist with the Wisconsin Department of Natural Resources where he was instrumental in developing regulations and guidance governing investigation and cleanup of contaminated sites. He was co-chair of the ASTM task group responsible for developing an ASTM standard guide for remediation by natural attenuation; was a member of a National Academy of Science committee on intrinsic remediation evaluating the scientific basis for natural attenuation as a remedy; and has been an instructor for numerous training courses on monitored natural attenuation, risk assessment, and modeling.


-B.S. (Geology and Geophysics) University of Wisconsin, Madison. 1982.
M.S. Program (Geology) Vanderbilt University, Nashville, Tennessee. 1983-1985.


OSHA 40-Hr HAZWOPER Training, 2013
OSHA 24-Hr HAZWOPER Training for UST Workers, 1991

Representative Experience

• Provided hydrogeologic support for remedial investigation/feasibility study of extensive chlorinated ethene solute plume and associated petroleum contamination in Tucson, AZ. Performed geochemical evaluation explaining distribution of chemicals of concern in aquifer. Developed human health risk assessment for soil and groundwater contamination involving vapor transport.

• Project manager for three petroleum storage tank sites in Winslow, Arizona. Providing oversight and direction of field sampling activities and interpretation of data. Development of work plans and coordination and scheduling of field operations. Directing in situ chemical oxidation pilot study involving geochemical evaluation of aquifer conditions. Designing geochemical sampling plans.

• Developing remedial investigation report for extensive chlorinated ethene solute plume in Phoenix, AZ area.

Prior Experience

1997-2012 Geosicence Resources Inc.

• Performed technical evaluation of proposed groundwater remediation to determine feasibility and potential efficacy for petroleum-contaminated site in southeastern Missouri involving extensive light non-aqueous phase liquid (LNAPL) contamination in an alluvial aquifer and extensive methyl tert-butyl ether (MTBE) solute plume impacting municipal water supply.

• Technical support for SESOIL modeling for cleanup level development for industrial site, San Francisco Bay area, California. Evaluated modeling and appropriate representation of volatilization and assisted in negotiating regulatory acceptance.

• Peer review and expert consulting on mercury and chlorinated hydrocarbon contamination at a MSW landfill, central Georgia. Performed comprehensive technical review of available data to evaluate chemical transport & fate for landfill gas and leachate sources and efficacy of monitored natural attenuation (MNA) for complex hydrogeologic and geochemical setting.

• Developed draft regulations for Missouri Department of Natural Resources to implement risk-based corrective action (RBCA) for petroleum storage tank sites. Developed alternative draft regulations for Missouri Petroleum Storage Tank Insurance Fund (PSTIF).

• Expert consulting on karst issues for petroleum release site, southern Missouri. Ongoing project providing review and technical support for site characterization, risk assessment and remedial design for site in karst setting on Missouri-Arkansas border.

• Water availability assessment for proposed subdivision, northern New Mexico. Geohydrologic evaluation of groundwater availability, oversight of well installation and pumping test, analysis of pumping test results and modeling of sustainability and impacts of groundwater withdrawal.

• Project management, expert consulting, expert witness and litigation support for mercury-contamination site in southeastern Wisconsin. Ongoing project involves alleged contamination from fill materials across property line, wetland and surface water impacts, solid waste disposal issues, groundwater-surface water interaction. Providing oversight and directing site characterization activities and coordinating with state and federal civil litigation and Superfund emergency response action.

• Risk assessment for former natural gas processing facility, western Nebraska. Included evaluation of contaminant and non-aqueous phase liquid (NAPL) distribution in fractured bedrock aquifer under influence of irrigation pumping and characterization of exposure from spray irrigation and crop uptake.

• Provided custom training on use of analytical solute transport models for Ohio Bureau of Underground Storage Tank Regulations (BUSTR). Focus on BIOSCREEN and AT123D models, including examination of practical impact of different model representations on results and decision-making.

• Developed guidance document on lines of evidence for evaluating natural attenuation and enhanced remediation of chlorinated solvents for DOE Savannah River Site (with T.H. Wiedemeier & Associates).

• Performed site review and developed risk assessment for TPH and BTEX contamination in soil and groundwater at a Kansas City-area trucking facility (for Williams & Co. Consultants and Missouri PSTIF).

• Provided training and consultation on risk-based decision-making to Missouri Department of Natural Resources and Petroleum Storage Tank Insurance Fund administrators and staff as prelude to administrative rule development.

• Provided training on natural attenuation as a remediation approach for contaminated sites to Canadian environmental professionals and regulators for Environmental Services Association of Alberta.

• Provided training on principles of contaminant transport and fate and parameter estimation for State of California Department of Toxic Substance Control staff.

• Developed and provided technical training on risk-based approaches to site remediation in cooperation with the Oregon Department of Environmental Quality.

• Provided training in applied transport and fate modeling for risk assessment to State of Kansas Department of Health and Environment remediation programs staff.

• Provided training on natural attenuation as a remediation approach for contaminated sites to Ohio Environmental Protection Agency staff.

• Expert witness in civil litigation regarding appropriate remedial action at a petroleum release site in southeastern Wisconsin.

• Co-developed and providing instruction for NGWA short course on advanced groundwater modeling techniques for evaluating natural attenuation and enhanced bioremediation.

• Expert peer review of feasibility study for PCB-contaminated sediments at the lower Fox River NRDA site in northeastern Wisconsin – performed for U.S. EPA Region 5.

• Expert peer review of groundwater flow model constructed for Ionia Landfill Superfund Site, Michigan – for U.S. EPA Region 5.

• Developed and presented 5-day training on monitored natural attenuation, contaminant transport and fate principles and parameter estimation, and applied soil and groundwater modeling for U.S. Army Corp of Engineers in Alaska.

• Transport and fate evaluation and modeling for risk-based closure of former dry cleaning facility in central Ohio.

• Preliminary assessment for PCB risk-based cleanup levels to support litigation of RCRA claim for a manufacturing facility in northeastern Wisconsin.

• Technical support for natural attenuation evaluation and model development to support RCRA closure at Giant Industries refinery, Bloomfield, NM.

• Strategic planning to incorporate evaluation of natural attenuation into overall facility management for RCRA closure and corrective action for major refinery facility in Texas.

• Technical peer review of modeling and technical basis for landspreading of petroleum-contaminated soil as a remediation alternative for FAA sites in Alaska.

• Site characterization and natural attenuation evaluation to support property transfer of closed dairy facility in Wisconsin with petroleum hydrocarbon contamination.

• Developed course materials and providing instruction for NGWA short courses “Transport and Fate Principles and Parameter Estimation” and “Applied Transport and Fate Modeling for Cleanup Level Determination.”

• Presented short course on natural attenuation for remediation of contaminated sites for Technical University of Denmark in Copenhagen.

• Remedial action feasibility evaluations for Texas UST sites including analysis of soil vapor extraction pilot test data and groundwater pump-test data (for Daniel B. Stephens & Associates).

• Expert witness on soil modeling and risk assessment in litigation regarding a RCRA facility closure in southern California. Contributed to development of Remedial Investigation/Feasibility Study report for site involving chlorinated solvent releases, metal contamination and perchlorate. Evaluation and interpretation of contaminant transformation and transport processes in thick vadose zone and groundwater.

1991-1997 Wisconsin Department of Natural Resources

• Expert witness on natural attenuation for litigation involving remedy selection for a landfill leachate plume at the Rhinelander Landfill. Evaluation of site hydrogeology, source characterization and contaminant distribution, and groundwater geochemistry. Reviewed and evaluated potential efficacy of proposed remedial actions.

• Developed nationally recognized guidance on the application of naturally occurring biodegradation as a remedial action. Provide state-wide oversight and direct the development and implementation of policy and guidance for the application of natural attenuation to cleanup of contaminated soil and groundwater in Wisconsin.

• Coordinated demonstration project for natural attenuation at petroleum release sites in Wisconsin with AMOCO and U.S. EPA Region 5.

• Provided training on use of natural attenuation as a remedial action to WDNR and other Wisconsin state agency staff.

• Invited speaker for American Petroleum Institute (API) Biodegradation Modeling Workshop (1994) on regulatory considerations for application of biodegradation models.

• Provided management and technical oversight of extensive modeling project for development of soil cleanup levels for Wisconsin. Responsibilities included design and development of project, evaluation and selection of appropriate unsaturated zone contaminant transport and fate models, performing and overseeing modeling work, and application of model results for development of generic soil cleanup levels for Wisconsin.

• Provided oversight and contributed to the development of a new user’s manual for the SESOIL model.

• Primary author of Wisconsin regulations for determination of soil cleanup levels (ch. NR 720) and evaluation and selection of remedial options (ch. NR 722) for contaminated sites. Contributed to development of other regulations in the NR 700 series for investigation and remediation of environmental contamination in Wisconsin.

• Developed guidance on determination of soil cleanup levels for polycyclic aromatic hydrocarbons (PAHs).

• Provided oversight and technical support for application and implementation of risk-based corrective action in Wisconsin.

• Provided technical support for remedial design, Wausau Water Supply Superfund site involving VOC contamination from multiple contaminant source areas and multiple groundwater plumes in a complex, heterogeneous river valley aquifer. Reviewed and approved proposed methodology for determination of soil cleanup levels. Provided oversight on development and application of a 3-dimensional groundwater flow model for plume capture analysis and evaluation of groundwater pumping strategies. Provided oversight on development and application of a soil gas contaminant transport model for design of soil remediation system using soil vapor extraction (SVE).

• Project hydrogeologist for National Presto Industries Superfund site. Provide project oversight and review for Remedial Investigation/Feasibility Study (RI/FS) involving VOC contamination from multiple contaminant source areas and multiple groundwater plumes in a complex, heterogeneous buried valley aquifer. Provided oversight for development and application of contaminant transport modeling using SESOIL for determination of soil cleanup levels. Provided oversight on development and application of a groundwater flow model and its use for plume capture analysis and evaluation of groundwater remediation options. Assisted in design of pilot test for large-scale soil vapor extraction (SVE) system and provided review and interpretation of results.

• Provided oversight on development of a 3-dimensional soil vapor transport model for preliminary design and evaluation of SVE system.

• Provided technical support for several additional Superfund sites, including review and interpretation of soil and groundwater sample results defining degree and extent of contamination, determination of background soil concentrations of heavy metals, review and design of sampling plans, and review of risk-based methods used for determination of cleanup levels for soil and groundwater.

• Provided review of risk assessments performed for several RCRA facility closures and corrective action sites. Reviewed and evaluated cleanup level calculations for two (2) Department of Defense (DoD) sites involving complex site conditions and combinations of contaminants, including explosives.

• Management and technical oversight of development and implementation of a comprehensive groundwater monitoring/leak detection program for a chemical UST tank farm at a RCRA facility. Evaluated and designated appropriate statistical methods for analysis and evaluation of groundwater monitoring data.

• Contributed to the development of U.S. EPA’s Soil Screening Guidance for Superfund. Provided technical review of proposed risk-based methodologies and exposure assessment criteria.

• Participated as invited state regulatory representative to U.S. EPA in strategic planning for development of a "National Risk Protocol" associated with the Superfund Reform Act of 1994.

• Provided training to professional staff of WDNR and environmental consulting firms on soil cleanup level determination and risk assessment.

• Instructed graduate and undergraduate students in geology, environmental toxicology, and environmental engineering classes and seminars at the University of Wisconsin - Madison and University of Wisconsin - Milwaukee on application of risk assessment methods in environmental regulation of contaminated sites, principles and application of environmental models in risk assessment and cleanup level determinations, the use of the SESOIL model, and use of natural attenuation as a remedial action for groundwater contamination.

• Provided technical support to WDNR solid waste management program on use of risk-based methods for determining acceptable levels of contamination for beneficial reuse of high-volume industrial solid wastes.

1985-1986 Independent Consulting - Geologist

• Evaluation of petroleum exploration potential for central and western Tennessee, including examination of regional groundwater systems and hydrogeologic implications for potential hydrocarbon accumulations. Optical and X-ray diffraction examination of well cuttings for completion data. Petrographic evaluation of cement-porosity relationships for reservoir rocks, central Appalachian Basin.


Wiedemeier, T.H., and M.J. Barden. 2006. Factors affecting the sustainability of monitored natural attenuation. Proceedings of the Fifth International Conference on Remediation of Chlorinated and Recalcitrant Compounds, May 22-25, 2006, Monterey, CA.

Wiedemeier, T.H., and M.J. Barden. 2006. Lines of evidence for evaluating biological and abiotic degradation of chlorinated solvents. Proceedings of the Fifth International Conference on Remediation of Chlorinated and Recalcitrant Compounds, May 22-25, 2006, Monterey, CA.

Wiedemeier, T.H., M.J. Barden, P.E. Haas, and W.Z. Dickson. 2006. Designing monitoring programs to effectively evaluate the performance of natural attenuation, in Practical Handbook of Ground-Water Monitoring (2nd edition), D.M. Nielsen (ed.), Lewis Publishers, Boca Raton, FL.

Wiedemeier, T.H., M.J. Barden, W.Z. Dickson, and D. Major. 2004. Multiple Lines of Evidence Supporting Natural Attenuation: Lines of Inquiry Supporting Monitored Natural Attenuation and Enhanced Attenuation of Chlorinated Solvents. U.S. Department of Energy, Office of Scientific and Technical Information, Oak Ridge, TN, WSRC TR 2003 00331.

National Research Council (contributing author). 2000. Natural Attenuation for Groundwater Remediation. National Academy Press, Washington, DC. 274 p.

Barden, M.J. 1997. Soil Cleanup Levels for Polycyclic Aromatic Hydrocarbons (PAHs) -- Interim Guidance. Wisconsin Department of Natural Resources, Bureau for Remediation and Redevelopment. PUBL RR-519 97, March 1997.

Yang, X., H. Glasser, R. Stoelting, M. Barden, G. Mickelson, J. Delwiche, and G. Alvarez. 1997. Natural attenuation demonstration in Wisconsin, in Fourth International Symposium on In-Situ and On-Site Bioremediation, v. 4(1). Battelle Press, Columbus, OH.

Barden, M.J. 1993 (revised 1994). Naturally Occurring Biodegradation as a Remedial Action Option -- Interim Guidance. Wisconsin Dept. of Natural Resources.

Hetrick, D.M., S. Scott, and M.J. Barden. 1992 (1994 revised). The New SESOIL User’s Guide. Wisconsin Dept. of Natural Resources, Bureau of Solid and Hazardous Waste Management, Emergency and Remedial Response Section, Publication PUBL SW-200 (revised 1994).


Practical Use of Statistics for Natural Attenuation Trend Analysis EST-0101. Environmental Institute for Continuing Education, 2003.

Natural Attenuation as a Remediation Approach – Responsible Risk Management. NMED UST Conference, Albuquerque, NM, November 16-17, 1998.

Evolving biogeochemical concepts for solute plumes in groundwater -- Natural attenuation as a remedial action. SETAC Midwest Chapter Spring Meeting, Green Bay, WI, 1997.

Natural attenuation as a remedial action -- What it is, how it works, and what's needed to use it. Wisconsin Water Well Association Annual Conference, Stevens Point, WI, February 6, 1997.

Summary of regulatory considerations and concerns for natural attenuation as a remedial action option for chlorinated organics, in U.S. EPA/Air Force Symposium on Natural Attenuation of Chlorinated Organics in Groundwater, Dallas, TX, September 11-13, 1996.

Wisconsin's approach to natural attenuation. ASTSWMO Annual Superfund Managers Conference, Phoenix, AZ, August 19-21, 1996.

Wisconsin’s Guidance on Naturally Occurring Biodegradation as a Remedial Action Option, in U.S. EPA/USGS Symposium on Intrinsic Bioremediation of Groundwater, Denver, CO, August 30 - September 1, 1994. EPA/540/R-94/515, p. 170, 1994.

Regulatory application of SESOIL for development of generic soil cleanup levels for Wisconsin. 8th National Conference on Contaminated Soils, University of Massachusetts, Amherst, MA, September 20-23, 1993.

Considerations for application of SESOIL to soil contamination field scenarios. 8th National Conference on Contaminated Soils, University of Massachusetts, Amherst, MA, September 20-23, 1993.


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