Oak Ridge ETTP
Characterization and Closure Documentation

RSI is performing site characterization of the ETTP site as a subcontractor to BJC. The typical CERCLA process involves a comprehensive RI/FS that leads to a ROD, which outlines all actions necessary to achieve site closure. Due to the need to initiate action on known areas of contamination, the ETTP RODs established cleanup standards and requirements. The risk based action/no further action determinations are post-ROD decisions. This site closure relies on a comprehensive characterization program to delineate the nature and extent of contamination, evaluate the site risks and remedial action alternatives, and confirm that the final site conditions meet an unrestricted industrial end use. RSI’s characterization and regulatory documentation scope involves 80 exposure units (EUs) in Zone 1 (outside the ETTP fence) and 44 EUs in Zone 2 (enriched uranium production area). To ensure final acceptance by the regulatory agencies within a time-frame that supports closure, a unique program blending traditional characterization with elements of MARSSIM and EPA’s Triad approach is being used by RSI at ETTP. The Core Team’s involvement, which includes representatives from DOE, EPA, and TDEC, is crucial to the success of this program. RSI prepared the site characterization plan for over 600 acres in Zone 1; conducted all field characterization, including sample management; and successfully communicated results to the regulators. Technical memoranda were prepared to summarize the characterization results for each EU Group, including a comparison of the characterization results to the remedial levels of the Zone 1 ROD and determination of whether the EU is a potential source to groundwater contamination. This effort resulted in a no further action determination for most of Zone 1, where surgical remedial actions with remedial limits were exceeded, and the preparation of a Phased Construction Completion Report for Zone 1. The same scope of work is underway for Zone 2.