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Cross Gold Mine <br />December 2024 U-12 <br /> <br /> <br />11. Geochemical Data and Analysis <br />The ore being processed at the Cross Gold Mine is blasted and ground telluride ore from the Boulder <br />granite/granodiorite. This will be crushed, ground to an exceptionally fine size (~150-micron) before <br />gravity and flotation separation. All ore that is brought to the Cross Gold Mine will be stored on the ore <br />pad prior to processing in the mine. <br />Ore materials have been tested in the past under Humidity Cell and Acid-Base Accounting. In 1995, <br />humidity cell tests were conducted on a composite of mine ore. Humidity cell tests subject ground ore <br />to agitation with water over an extended period to simulate precipitation mixing with material stockpiled <br />or otherwise stored in a manner exposed to weather. The results of this test are shown in Table U-3. <br />Also in 1995, the operator conducted whole rock and acid neutralizing potential analysis on the same <br />composite ore. These results can be seen in Table U-4. Both sets of geochemical analysis are included <br />in Appendix U-2 for CDRMS benefit, but both are also already available in CDRMS files from Cross <br />Gold Mine submittals in 1995. <br />The humidity cell test shows very low cumulative acidity and a pH consistently between 6 and 8. Heavy <br />metal concentrations are below detection limits at 10, 20, and 30 weeks of testing, showing a lack of <br />metals leaching from the mine ore. Net neutralizing potential results were 83.7 tons CaCO3/Kton. <br />According to the EPA Office of Solid Waste, a net neutralizing potential greater than 20 CaCO3/Kton is <br />considered clearly not acid producing. Based on this standard, the ore at the Cross Gold Mine is not <br />acid producing. <br />Ore and tailings will be sampled as part of process quality control, with periodic results being provided <br />to DRMS. Tests will be conducted on tailings material every 5000 tons of tailings generated and <br />reported to the Division. Sampling and testing of ore will be conducted on a similar schedule (one test <br />every 5000 tons). <br /> <br />