Kristi Diller is geologist with over 10 years of environmental consulting experience focused on site characterization and remediation. She specializes in complex site assessments, remedy selection, remedial design, and remedial actions at industrial and Department of Defense sites. She designs and executes field investigations, monitoring programs, and remedial actions for a range of media (groundwater, soil, soil gas) and contaminants (chlorinated solvents, petroleum, metals, perfluoroalkyl substances, etc.). Ms. Diller earned a B.S. in Geological Sciences from the University of Idaho and a M.S. in Geological Sciences from Arizona State University. She is a registered geologist in the State of California.
The shallow aquifer beneath Site 24 (former dry cleaning facility) at the former Naval Station Treasure Island was impacted by chlorinated volatile organic compounds (cVOCs). The site remedy included groundwater treatment using a combination of in situ chemical reduction (ISCR) and in situ bioremediation (ISB) to degrade saturated zone cVOC mass while reducing potential for generation of regulated intermediate dechlorination products. Microscale zero-valent iron (to promote ISCR) and an electron donor (to promote ISB) were injected into a grid of temporary injection points. Within three months of injection, groundwater cleanup goals in 55% of the treatment area were achieved, reducing average cVOC concentrations from 15 micromoles per liter (mol/L) to 0.1 mol/L. Over the following year the remedy continued to perform and by month 18, 90% of the former plume area meets cleanup goals. The field approach, lessons learned, and results from two years of performance monitoring will be presented.