
M.S., Natural Resources, Cornell University, Ithaca, New York, 2001
B.S., Biology, Villanova University, Villanova, Pennsylvania, 1997
Hazardous Waste Operations and Emergency Response 40‑Hour Certification (2002; annual refreshers)
First Aid and CPR (2026)
Society for Environmental Toxicology and Chemistry
Ecological Society of America
Maryann Welsch Consultant (207) 800-3808 Portland, ME mwelsch@integral-corp.com
Ms. Maryann Welsch is an environmental scientist with more than 20 years of experience working with industrial clients of regulated community and government entities to assess and reduce environmental risks and damage. She has provided strategic support and technical analyses on a variety of chemicals, including per- and polyfluoroalkyl substances (PFAS), petroleum compounds, dioxins, PCBs, PAHs, and metals to help clients and regulators understand the significance of ecological exposures and the potential for risks. As a project manager, Ms. Welsch collaborates with multidisciplinary project teams to deliver results in support of remedial investigations, feasibility studies, ecological risk assessments, natural resource damage assessments (NRDAs), ecosystem restoration, sediment management, and expert reporting.

Beneficial Use of Contaminated Sediments: Focused Review of Treatment Technologies
Poster
January 30 2025Ecological Risk Assessment
Natural Resource Damage Assessment
Contaminated Sediments
Welsch, M., S. Bentsen, and M. Henning. 2025. Beneficial use of contaminated sediments: critical review of treatment technologies. Integrated Environmental Assessment and Management. doi.org/10.1093/inteam/vjaf046.
Henning, M., M. Welsch, and X. Santiago. 2023. Expert Analysis: Enviro justice can help cos. with regulators, communities. Law360, New York, NY. March 9. https://www.law360.com/articles/1583250/enviro-justice-can-help-cos-with-regulators-communities.
Henning, M., and M. Welsch. 2023. Opportunities for meaningful environmental justice actions by the regulated sector. JDSupra. July 12. https://www.jdsupra.com/legalnews/opportunities-for-meaningful-9693652.
Yavitt, J., J. Burtis, K.A. Smemo, and M. Welsch. 2018. Plot-scale spatial variability of methane, respiration, and net nitrogen mineralization in muck-soil wetlands across a land-use gradient. Geoderma 315:11–19.
Welsch, M., and J.B. Yavitt. 2007. Microbial CO2 production, CH4 dynamics and nitrogen in a wetland soil (New York State, USA) associated with three plant species (Typha, Lythrum, Phalaris). Eur. J. Soil Sci. 58:1493–1505.
Welsch, M., and J.B. Yavitt. 2003. Early stages of decay of Lythrum salicaria and Typha latifolia in a standing-dead position. Aquat. Bot. 75:45–57.
Welsch, M., S. Bentsen, and M. Henning. 2025. Beneficial use of contaminated sediments: Focused review of treatment technologies. 12th International Conference on the Remediation and Management of Contaminated Sediments. Tampa, Florida. January.
Barra, B., H. Jones, and M. Welsch. 2023. Long-term ecological monitoring of New Bedford Harbor over 28 years. 11th International Conference on the Remediation and Management of Contaminated Sediments. Austin, Texas. January.
Welsch, M., C. Archer, H. Loso, C. Puopolo, H. Patterson, H. Temme, and A. Gorski. 2021. Developing site-specific uptake factor relationships for a PFAS investigation and risk assessment at a flood control system in Minnesota. 42nd Annual Meeting of SETAC North America, Ecological Risk Assessment for Contaminants of Emerging Concern. November.
Archer, C., H. Loso, H. Patterson, C. Puopolo, M. Welsch, H. Temme, and A. Gorski. 2021. PFAS investigation and risk assessment at a flood control system in Minnesota. 42nd Annual Meeting of SETAC North America, Ecological Risk Assessment for Contaminants of Emerging Concern. November.
Welsch, M., B. Ruffle, H. Jones, J. Bleiler, R. Damera, and F. Mahvi. 2015. Evaluating risks to benthic invertebrates and fish at an urban waterfront site on the Lower Anacostia River. North Atlantic Chapter of SETAC Meeting.
Hurley, K., L. Saban, and M. Welsch. 2009. Practical considerations of implementing a natural resources damage assessment restoration project. National Conference on Ecosystem Restoration, Los Angeles, CA.
Welsch, M. 2007. Ecological factors to consider when selecting a mitigation site. Law Seminars International Workshop on Mitigation and Conservation Banking. Seattle, WA.
Welsch, M., T. Deshler, S. Pierce, and S. Reiersgaard. 2004. Monitoring changes in wetland habitat functions following the introduction of wastewater effluent from cheese manufacturing. SETAC 25th Annual Meeting, Portland, OR.
Johns, D.M., L. Saban, M. Welsch, M. Luxon, D. Pelletier, and C. Jackson. 2004. Use of habitat suitability index models to scale site-specific injury for multiple resources. SETAC 25th Annual Meeting, Portland, OR.
Johns, D.M., L. Saban, M. Luxon, and M. Welsch. 2003. Establishing habitat valuations for HEA. SETAC 24th Annual Meeting, Austin, TX.