|
|
EPA/540/AR-93/517
Abstract: The Toronto Harbour Commisioners (THC) developed a soil treatment train in order to treat inorganic and organic contaminants in soils to below the THC Criteria Levels for Industrial Soils. The treatment train consisted of three soil remediation technologies: an attrition soil washing technology, inorganic removal by chelation and a chemical and biological treatment to reduce organic contaminants. The overall process sequence is determined by the specific contaminants in the soil to be treated. The developers claim that the gravel, sand and fine soil products will meet the THC criteria for reuse as fill material at industrial/ commercial sites was achieved by the sand and gravel products. The fine soil fraction as a result of biological processing did show significant reductions in polynuclear aromatic hydrocarbons (PAHs), however benzo(a) pyrene was above the criteria level of 2.4 mg/kg. The bioslurry process also exhibited limited reductions in oil and grease. The metals contamination levels actually encountered during pilot-scale processing of the test soil were so low that there was no need to use the metals removal process. The costs of the treatment system were examined on both an integrated and on a unit process basis. The overall cost of operation of a 6.6 tons per hour soil wash, metals removal and bioslurry treatment train is estimated at $219 per ton. The individual process costs that make up this estimate are:soil washing ($80/ton of feed soil), metals removal($96/ton of feed soil), and the bioslurry process ($43/ton of feed soil). Contact:
|
|