Long-Term Effects of Dredging Operations Program. Development of a Simplified Column Test for Evaluation of Thickness of Capping Material Required to Isolate Contaminated Dredged Material

摘要

A procedure using a small-scale leaching column was developed for predicting the cap thickness required to chemically seal contaminated dredged sediment from the overlying water column. Several parameters, including dissolved oxygen depletion rates and release rates of ammonium-nitrogen, orthophosphate-phosphorus, and manganese, were evaluated as tracers for use in the predictive test. In addition, several tests were run using potassium chloride amendments to the contaminated sediment prior to capping to determine if this salt would be a suitable tracer. Dissolved oxygen depletion and ammoniumsion, orthophosphate-phosphorus release was also an effective tracer. Use of managanese or potassium chloride as tracers proved ineffective. Keywords: Dredged material, Leaching, Organic water pollutants, Tracers, contaminants.