The Little Scioto River (LSR) Superfund site located west of the city of Marion, Ohio, consists of two separate Operable Units (OUs): the Little Scioto River (OU1) and the former Baker Wood Creosote (BWC) facility that was the source of the creosote contamination of in the river sediment beginning in the 1890s (OU2). This project focuses on the remediation of OU1 which is a 3.25-mile segment from just north of State Route 95 (Marion-Agosta Road) to State Route 739 (Marion-Green Camp Road). The project excavates over 105,000 CY of sediment by dewatering segments of the river, excavating and replacing the soil, and disposing of the sediment offsite.
In addition to the potential capital cost savings proposed by the Value Team (36% of the project cost), the team generated several recommendations which would expedite construction, reduce material handling, and reduce the risk of delays to contractors during storm or flood events. The Value Team proposed the construction of a temporary channel to divert the river flow around the three-mile construction site to eliminate pumping operations during construction which would increase the efficiency of construction and improve worker safety. Another key recommendation was to excavate from the bank instead of from inside the channel in order to eliminate the need for soil stabilization for equipment and the requirement to double handle contaminated sediment between dirty haul trucks and clean haul trucks. Finally, the Value Team identified an opportunity to optimize the project construction phasing which would reduce the duration of construction from 48 months to 36 months.