SITE Demonstration of the Basic Extractive Sludge Treatment Process

Abstract

The Superfund Innovative Technology Evaluation (SITE) Program, in cooperation with EPA Region 5, the Great Lakes National Program Office (GLNPO), and the U.S. Army Corps of Engineers (COE) planned and executed a pilot-scale evaluation of the Basic Extractive Sludge Treatment (B.E.S.T.®) process on sediment samples obtained from the Grand Calumet River in Gary, Indiana. Two separate sampling locations were selected based upon previous data. One location had sediments with total polychlorinated biphenyl (PCB) concentrations averaging 10 mg/kg, and total polynuclear aromatic hydrocarbon (PAH) concentrations averaging 520 mg/kg. The other location had sediments with average total PCB and PAH concentrations of 427 mg/kg and 72,000 mg/kg, respectively. The sediment samples were segregated by location, then screened, homogenized, and stored prior to treatment. A total of ten batches of sediments were treated (five for each sample location).

Results showed that of the samples which had low original contaminants concentrations, 96 percent of the PAHs and >99 percent of the PCBs were removed following seven sequential extractions. Treated samples which had high original contaminant concentrations were found to have removal efficiencies of >99 percentfor both PAHs and PCBs. Costs for applying this technology were estimated at $94.19/ton (assuming the system is on-line 80 percent of the time) excluding fixed costs associated with system mobilization/ demobilization and setup, and profit.