SERDP and ESTCP investments in contaminated sediment management research achieved a major milestone with the specification of activated carbon placement as part of the remedy in the Records of Decision (RODs) for Joint Base Pearl Harbor-Hickam (JBPHH) in Hawaii, and for the Hunters Point Naval Shipyard (HPNS) in California.
Sediment contamination is a significant liability for the Department of Defense (DoD), with overall liabilities estimated to approach $2 billion. SERDP and ESTCP identified in situ remedial alternatives for sediments as a critical priority research need in a 2004 Workshop Report. SERDP first invested in 2004 with Stanford University on the use of activated carbon (AC) to sequester organic contaminants. With that initial seminal research, the Programs went on to fund demonstration projects at the Army’s Aberdeen Proving Ground (ESTCP Projects ER-200835 and ER-200825), HPNS (SERDP Project ER-1207), Naval Air Station Dallas (SERDP Project ER-1493), and the Puget Sound Naval Shipyard (ESTCP Project ER-201131) (see Activated Carbon Amendments for In Situ Stabilization of Contaminated Sediments Move from the Bench to the Field). Based on these very successful demonstration projects, activated carbon as a sediment remedy is being tested at contaminated sediment sites throughout the world, and is acknowledged by the US Environmental Protection Agency as an established remedial technology (see EPA’s 2018 Fact Sheet). The culmination of these efforts is the RODs for JBPHH and HPNS.
What is an Activated Carbon Sediment Remedy?
Activated carbon is a well-established method for removing organic contaminants in water. Carbon filters are used to clean industrial and municipal wastewater and are commonly sold for use in home filtration units to polish drinking water. AC works by stripping binding organic contaminants such as polychlorinated biphenyls (PCBs) and pesticides from the water. Applying this same principle, research funded by SERDP demonstrated that adding AC into sediments has the same effect; organic contaminants are bound up and are then not available for uptake into organisms. Additions of as little as 2 percent AC resulted in 10- to 100-fold reductions in PCB uptake into marine organisms (see In Situ Sediment Remediation).
Activated Carbon Web Site
SERDP and ESTCP announce the posting of a technology transfer web site: Implementation of In Situ Activated Carbon Remedies at Contaminated Sediment Sites. This web site focuses on providing key technical considerations for DoD Remedial Project Managers for using AC as an in-water remedial alternative for managing sediment sites.
Information contained on the web site includes an overview of the science of carbon sequestration, design and construction considerations, monitoring tools used to demonstrate efficacy of the remedy, detailed case studies on AC remedied sites, and provides references and additional resources. The site is active and will be updated as new and pertinent information becomes available.