Specifically, two pilot-scale tests were conducted in-situ to support the full-scale reductive dechlorination system design. In the first pilot-test, an electron donor was introduced via four injection wells to determine the applicability of the selected electron donor (molasses) and optimize the geochemistry conditions (e.g., pH) for enhanced reductive dechlorination via electron donor injection. In the second pilot-test, a tracer (fluorescein) and the selected electron donor were injected into two injection wells to estimate (1) the mobile and immobile porosity values of the aquifer, (2) the transformation rate of TCE, and (3) the ambient groundwater velocity. Following the completion of both pilot-scale tests, the full-scale remediation system was designed and implemented in a layout with four major transects, each of which consists of a number of injection wells in areas with relative high TCE concentrations . In addition, the alternative anaerobic TCE transformation mechanism was evaluated because the traditional sequential reductive dechlorination pathway of TCE—cis-DCE—vinyl chloride —ethene was not observed at the site, and the outcome of which will also be presented.