Support for characterization, grout formulations, and stabilization of K-1407-B and K-1407-C pond sludges

The Oak Ridge Gaseous Diffusion Plant (ORGDP) has generated large quantities of mixed hazardous and radioactive wastes over the years. Most of these wastes are contained as sludges in two large treatment and settling ponds, K-1407-B pond and K-1407-C pond. The federal mandate requiring that all surface impoundments be discontinued and closed by November 1988 makes the need for remedial action for these ponds very apparent. Both ponds were statistically sampled, and the sludge and clay layers in these ponds were completely characterized. Cement stabilization was chosen as the treatment method for processing these pond sludges. Laboratory-scale cement fixation studies were performed to develop a grout formulation that would allow the Sludge Treatment Facility (STF) at ORGDP to stabilize hazardous wastes so that they would meet or exceed applicable compressive strength and leachability requirements and thus qualify for delisting from hazardous to nonhazardous. A process flow sheet was developed that detailed operating procedures and equipment requirements for the handling of waste materials from the raw sludge to the final hardened concrete forms. Special problems associated with handling, pumping, processing, and moving of the raw sludge, wet concrete, and cast concrete have been investigated. The STF has been in operation sincemore » April 1987 stabilizing sludge from K-1407-C pond. Problems and operating experiences to date at the STF are discussed in this report. 18 refs., 5 figs., 32 tabs.« less