Yonas Zemuy is a Senior Principal Engineer based in California with more than 20 years of experience focused on geoenvironmental and civil infrastructure projects. His projects often include landfill design, expansion, and closure; geosynthetic liners; construction engineering support and quality assurance; geotechnical investigations and testing; regulatory support; and project management.
Rachel Zajac-Fay is a Senior Scientist based in Florida with 17 years of experience focused on ecotoxicology, ecological risk assessment, contaminated site assessments, and emerging contaminants.
Stephanie Zinn is a Principal Professional Water Resources Consultant based in California with more than 15 years of experience in National Pollutant Discharge Elimination System (NPDES) water-quality compliance, multi-benefit water-supply solutions, remote-sensing research, and water-resource policy.
Jean Zodrow, PhD, is a Principal Scientist based in Colorado with more than 18 years of experience focused on toxicology, ecological risk assessment, site characterization, regulatory guidance, and risk-based screening criteria and ecological risk assessment of per- and polyfluoroalkyl substances (PFAS).
Peter Zeeb is a Senior Principal Hydrogeologist based in Massachusetts with more than 25 years of experience focused on investigation and remediation strategy at some of the most challenging sites in the country, including CERCLA-regulated sites in New England and the Midwest, as well as numerous state-regulated sites. Peter also serves as Chair of Geosyntec's Board of Directors.
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