Appendix H

A series of flotation tests had been conducted at DML on the three individual composites that comprise MC-1. The initial scope of that test work was to evaluate if:

The microbiological oxidation of iron and sulfur constitutes two key processes in mineral biotechnology. Both mesophilic and thermophilic bacteria have been described which can utilize inorganic compounds of Fe and S as electron donors (3, 5, 6). At present, although thermophiles are characterized by superior oxidation rates, only mesophilic iron- and sulfur-oxidizing acidophiles are used in large-scale leaching processes for metal recovery from sulfide ores.

This test method covers a procedure that accelerates the natural weathering rate of a solid material sample so that diagnostic weathering products can be produced, collected, and quantified. Soluble weathering products are mobilized by a fixed-volume aqueous leach that is performed, collected, and analyzed weekly. When conducted in accordance with the following protocol, this laboratory test method has accelerated metal-mine waste-rock weathering rates by at least an order of magnitude greater than observed field rates.

This letter report presents the results of the 2010 geotechnical testing program on scavenger and cleaner tailings. The results are also compared with the previous test programs in 2007 and 2009.