Superfund Research Program
Pilot-scale Research of Novel Amendment Delivery for in situ Sediment Remediation
Project Leader: Upal Ghosh
Grant Number: R01ES016182
Funding Period: 2007-2010
Final Progress Reports
In this past year of research, Dr. Ghosh’s team performed laboratory-scale treatability studies using PCB and DDT-impacted sediment samples collected from two field sites and worked with site managers and regulators to plan pilot-testing proposed in this research. The first field site is a tidally influenced creek, contaminated with polychlorinated biphenyls (PCBs) located at a U.S. Army site in Virginia. The second site is the Frankford inlet in Philadelphia, PA. Historic chemical manufacturing in the vicinity of this site resulted in contamination of the sediments with toxic chemicals including DDT, DDD, and DDE. Laboratory bioaccumulation tests were conducted to evaluate the impact of activated carbon sorbent amendments in reducing PCB bio-uptake by benthic organisms (Leptocheirus plumulosus) that form the base of the aquatic food chain. Amendment of sediment with activated carbon led to a decrease in both uptake of PCBs in the food chain, and diffusive release of PCBs from sediment into overlying water.
Though lab results are promising, the effectiveness of activated carbon in reducing PCB bioavailability under field conditions is still uncertain. A pilot-scale demonstration was conducted at the U.S. Army site in Virginia involved two side-by side plots (treated and untreated) in the creek. The research team applied SediMite pellets containing activated carbon using a boat-mounted dispersion device. The team has performed baseline monitoring at the site before application, and researchers continued field sampling after application and will assess bioavailability changes after one year of carbon application.