UTILIZING THE RIGHT MIX OF ENVIRONMENTAL CLEANUP TECHNOLOGIES

The Savannah River Site (SRS) Figure 1 is a 310-square-mile United States Department of Energy nuclear facility located along the Savannah River near Aiken, South Carolina. During operations, which started in 1951, hazardous substances (chemicals and radionuclides) were released to the environment. The releases occurred as a result of inadvertent spills and waste disposal in unlined pits and basins which was common practice before environmental regulations existed. The hazardous substances have migrated to the vadose zone and groundwater in many areas of the SRS, resulting in 515 waste units that are required by environmental regulations, to undergo characterization and, if needed, remediation. In the initial years of the SRS environmental cleanup program (early 1990s), the focus was to use common technologies (such as pump and treat, air stripping, excavation and removal) that actively and tangibly removed contamination. Exclusive use of these technologies required continued and significant funding while often failing to meet acceptable clean-up goals and objectives. Recognizing that a more cost-effective approach was needed, SRS implemented new and complementary remediation methods focused on active and passive technologies targeted to solve specific remediation problems. Today, SRS uses technologies such as chemical/pH-adjusting injection, phytoremediation, underground cutoff walls, dynamic underground stripping, soil fracturing, microbial degradation, baroballs, electrical resistance heating, soil vapor extraction, and microblowers to more effectively treat contamination at lower costs. Additionally, SRS's remediation approach cost effectively maximizes cleanup as SRS works proactively with multiple regulatory agencies. Using GIS, video, animation, and graphics, SRS is able to provide an accurate depiction of the evolution of SRS groundwater and vadose zone cleanup activities to convince stakeholders and regulators of the effectiveness of various cleanup technologies. Remediating large, complex groundwater plumes using state of-the art technologies and approaches is a hallmark of years of experience and progress. Environmental restoration at SRS continues to be a challenging and dynamic process as new cleanup technologies and approaches are adopted.