AN INVESTIGATION OF LANDFILL DISPOSAL OF BLAST FURNACE SLAG FROM SECONDARY LEAD SMELTERS.

摘要

Problem. Before the promulgation of Resource Conservation and Recovery Act (RCRA) regulations in 1976, all discard slags from secondary lead smelting were disposed on land in open dumps. all slags contain some concentrations of potentially hazardous waste including lead, arsenic, barium, and other heavy metals. However, solubility tests used prior to RCRA's EP toxicity test mandate, did not indicate significant leaching of these metals. Since approximately 1/3 to 1/2 ton of slag is generated per ton of lead produced and the industry estimates an additional cost of {dollar}40.00 per ton of slag if it has to be disposed of as a hazardous waste, the economic impact may eliminate the industry's competitiveness and close down the smaller plants.; This investigation of blast furnace slag from secondary lead smelters is proposed to develop a data base through testing of representative samples of slag and determine if there is a need and justification for modifying RCRA's testing procedure or interim disposal requirements. It would increase the Environmental Protection Agency's national pool of information on hazardous wastes and contribute to making more knowledgeable decisions in implementing hazardous waste management while also providing the slag producers with suitable environmental guidance for disposing their solid waste.; Procedures. This research primarily involved a laboratory program of extracting lead from split slag samples to compare EPA's EP toxicity testing protocol with a potentially equivalent EP toxicity test and a comparative analysis to evaluate the appropriateness of EPA's EP toxicity test being used to determine secondary lead smelter slag hazardousness. A literature search of other lead slag analysis data was also part of the research program.; Findings. The investigator found that in the area of environmental regulations the utilization of the EPA EP testing protocol was not representative of real landfill conditions and had poor reproducibility when compared to the Alternative EP testing protocol. The use of the Alternative EP protocol to characterize and classify blast furnace slag would be more appropriate than the EPA EP protocol.