Groundwater and soil remediation Groundwater hydrologyContaminant migration and fateLitigation support and expert witnessTechnical training and outreachSubstrata brings exceptional expertise in subsurface contamination and remediation issues to public and private clients worldwide. Substrata focuses on strategic consulting services for challenging remediation and water resource problems. Substrata brings 30 years of consulting experience in groundwater flow and chemical migration, complex contaminant mixtures, modeling methods applied to groundwater and soil restoration, attenuation of chemicals in the subsurface, vapor intrusion characterization and mitigation, groundwater management, and aquifer hydraulics. Through careful application of innovative site characterization strategies and a thorough understanding of regulatory frameworks, Substrata has led the development of consensus-based conceptual site models to manage risks on a wide variety of projects, including upstream and downstream petroleum sites, releases of per- and poly-fluorinated alkyl substances (PFAS), chlorinated solvents, pesticides, metals, radionuclides, and many other chemicals. Substrata has extensive experience applying and teaching the principles of risk-based decision making to develop risk-based conceptual models. Substrata has focused on improving management decisions under a variety of US and international regulatory frameworks, including CERCLA, RCRA, and state cleanup programs. With a deep background in the modeling of groundwater flow and contaminant migration, Substrata has effectively applied these skills for groundwater management, remedial design, risk assessment, and litigation support. Founder Eric Nichols has conducted and managed research and development to foster innovative techniques to save cost and improve outcomes. A lifelong promoter of best practices and a professional educator, Nichols is an acclaimed speaker and teacher in his specialty areas.