Geology and environmental remediation: Savannah River Site, South Carolina

Delineation and understanding the geology and hydrogeology of a contaminated site is a fundamental requirement for environmental remediation. Successful environmental remedial programs are composed of interdisciplinary teams of scientists, including geologists, engineers, chemists, mathematicians, biologists, and others. The approach employed is analogous to petroleum exploration that relies on an interdisciplinary team that bases their interpretations and recommendations on understanding the geological, depositional, and structural setting. Good interactive communication between disciplines is a necessary component to the success of both environmental and petroleum programs. In the environmental and petroleum industry, the selection and deployment of appropriate technologies for the problem rely on initial characterization activities. In the environmental arena, geology and hydrogeology control the migration of contaminant plumes and affect the performance of remediation technologies. At the Savannah River Site (SRS) in South Carolina, which is underlain by interbedded and heterogeneous coastal-plain sediments, understanding depositional and postdepositional processes supports building a hydrogeological model and guides proper selection and optimization of remediation technologies. Accurately mapping the continuity of critical sediment layers can aid in locating areas where contamination has migrated and can provide a cost-effective basis for directing characterization to target intervals. This type of information can then be used to refine existing remediation systems or assist in designing new systems. A thorough understanding of the subsurface coupled with biological and/or chemical effects is essential for successful engineering implementation of the chosen technology. This paper will address an integrative and philosophical approach for environmental remediation and summarize local hydrogeology and background of a waste site at SRS. Examples will be discussed that relate geology to specific remediation technology and implementation decisions in the program.