Evaluation of the TCLP method for two mill tailings.
Mine Drainage and Surface Mine Reclamation. Volume I: Mine Water and Mine Waste. Vol. I. Pittsburgh, PA: U.S. Bureau of Mines, 1988 Apr; :200-205
Initial results are reported on determining the applicability of the toxicity characteristic leach procedure (TCLP) in predicting the potential for heavy metal contamination associated with mining wastes. TCLP tests, variations of the TCLP tests, and baseline tests were run on tailings samples from two mills to determine the sensitivity of laboratory protocol to slight procedural errors and to determine if any inherent factors produced a fatal flaw in using the test to evaluate mine tailings. Results from tailings A showed that metal ion concentration increased with higher liquid-to-solid ratios, with an increased volume of HOAc, and with longer mixing times. Results from tailings B showed the same general trends, but varied significantly in sensitivity to variations. The average yield of the standard TCLP tests as a percentage of the total digestion assay is 20% for tailings A and 10% for tailings B. This is a significant difference between the two types of tailings. Evaluation of these initial results indicates that the sensitivity of the three parameters to laboratory errors is probably acceptable if laboratory procedures are followed with normal attention to detail. These results are only the initial phase of a systematic evaluation of the TCLP method. Future research should emphasize how well the TCLP test actually simulates mine waste contamination phenomena. In particular, studies should focus on the applicability of the extraction fluid, chemical and mineralogical effects in and around the disposal area, time, pH effects, and oxidation effects.
Heavy-metals; Heavy-metal-poisoning; Metals; Metal-compounds; Sensitivity-testing; Sampling; Sampling-methods; Laboratory-testing; Oxidation
IH; Conference/Symposia Proceedings
Mine Drainage and Surface Mine Reclamation. Volume I: Mine Water and Mine Waste