Elisabeth Hawley is a Senior Consultant based in northern California with 16 years of experience advancing environmental remediation projects involving site characterization, fate and transport, remediation, strategies to achieve site closure, and litigation support services.
Her area of expertise focuses on per- and polyfluoroalkyl substances (PFAS) and other contaminants of emerging concern such as 1,4-dioxane; 1,2,3-trichloropropane; N-nitrosodimethylamine (NDMA); and more.
Elisabeth has worked extensively on a range of PFAS projects since 2011. These projects have included the design and execution of PFAS site investigation work plans, preparation of field sampling protocols, assessment of PFAS source(s) and fate and transport, and development of innovative PFAS treatment technologies. She is skilled at designing PFAS sampling plans and interpreting results, advancing innovative remediation techniques, and supporting clients" litigation needs. As co-chair of Geosyntec's PFAS practice, she is a leader in applied research advancements and the current state of knowledge regarding PFAS regulations, transformations and treatment. Funded by the U.S. Department of Defense"s Strategic Environmental Research and Development Program (SERDP), Elisabeth is preparing guidance on the top five lines of evidence used to assess the effectiveness of PFAS treatment technologies. On behalf of the Environmental Security Technology Certification Program (ESTCP), she managed site-specific treatability testing that demonstrated the effectiveness of an in-situ technology to destroy perfluorocarboxylic acids and polyfluorinated precursors -- thermally-enhanced persulfate oxidation at low pH.
Another area of practice is remediation management at complex sites including use of adaptive site management, monitored natural attenuation over long timeframes, technical impracticability (TI) waivers, and similar state designations, as well as transitions from active to passive remedies. Elisabeth provided support to the Interstate Technology and Regulatory Council (ITRC) Remediation Management of Complex Sites team in developing their guidance document and internet-based training session on adaptive site management. She has developed site-specific remediation management strategies and evaluated technical impracticability at several Federal sites.