a b s t r a c tA storage pond dike failure occurred at the Tennessee Valley Authority Kingston Fossil Plant that resulted in the release of over 3.8 million cubic meters (5 million cubic yards) of fly ash. Approximately half of this material deposited in the main channel of the Emory River, 3.5 km upstream of the confluence of the Emory and Clinch Rivers, Tennessee, USA. Remediation efforts to date have focused on targeted removal of material from the channel through hydraulic dredging, as well as mechanical excavation in some areas. The agitation of the submerged fly ash during hydraulic dredging introduces river water into the fly ash material, which could alter the redox state of metals present in the fly ash and thereby change their sorption and mobility properties. A series of extended elutriate tests were used to determine the concentration and speciation of metals released from fly ash. Results indicated that arsenic and selenium species released from the fly ash materials during elutriate preparation were redox stable over the course of 10 d, with dissolved arsenic being present as arsenate, and dissolved selenium being present as selenite. Concentrations of certain metals, such as arsenic, selenium, vanadium, and barium, increased in the elutriate waters over the 10 d study, whereas manganese concentrations decreased, likely due to oxidation and precipitation reactions.Published by Elsevier Ltd.

The concept of contaminated sediment treatment producing a useful product has emerged in recent years, motivated by the cost of sediment disposal and by recognition of sediment as a resource rather than a waste. Contaminated sediment presents unique challenges for treatment, however, due to the character and complexity of the matrix, and the logistics and economics involved in coupling the process with a dredging operation. The objectives of this document are to capture the technical status of several promising treatment technologies of this type, to describe the process efficiency in terms of mass balance, to understand pre-treatment and posttreatment processing requirements, and to estimate full scale implementation costs at a scale compatible with a dredging operation. Overall, the document overlays a consistent and transparent structure on the comparative evaluation with the objective of providing an equivalent basis for comparison between these and other candidate treatment processes, such that it has utility of remediation to project managers and others engaged in technology selection efforts. Relying on publicly available demonstration reports, the following technologies were evaluated in depth: JCI/Upcycle rotary kiln thermal treatment/light-weight aggregate (LWA); Cement-Lock ® technology/cement; Minergy ® glass furnace technology/glass aggregate; and BioGenesis SM sediment washing process/manufactured soil. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.

P,-' 5 18. SUBJECT TERMS (Continued). ARCS Dredging Remediation Contaminant Great Lakes Sediment Disposal Heavy metals Treatment Dredged material PCBs Water quality 19. ABSTRACT (Continued). objective for the ARCS program is to evaluate and demonstrate remedial options, including removal, immobilization, and advanced treatment technologies, as well as the "no-action" alternative. The purpose of this study was to identify technologies that may be feasible for remediating Great Lakes contaminated sediment and that should be considered for demonstration under the ARCS program. Fechnologies reviewed include those involving removal of contaminated sediment with subsequent transport, treatment, containment, or disposal, and those for nonremoval alternatives, such as in situ treatment or containment of the contaminated sediment. Principal sources of information for the review are technology assessments for management of hazardous waste or contaminated sediment published by the USEPA, the Corps of Engineers, the International Joint Commission Great L.akes Water Quality Board, and others. Published information is supplemented with recent data and experiences from LIST OF TABLES No.

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