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TESTING OF MATERIALS <br /> Braun incorporated both field and laboratory evidence to investigate the materials that had potential for <br /> producing free sulfur ions. However, prior to the collection of site-specific evidence,a review of the <br /> surface waters and the drainage tunnels within the Cripple Creek district found the waters to be mostly <br /> neutral in pH and treatment of those waters for pH has not been historically necessary. The reasons are <br /> due to the low levels of exposed sulfides in the district and the amount of buffering that naturally exists <br /> in the rocks. Using this as a guideline, it would be expected that any specific property located within the <br /> district would have similar characteristic to the rest of the district. <br /> Site Inspection and Data <br /> Braun engineers performed site inspections of the disturbed areas within the Mineral Mountain project <br /> area during June and July 2014. During the inspections, no evidence was found of rock destruction that <br /> occurred as a result of any modern leaching, nor was any significant evidence found of any negative <br /> affects to grasses and soils immediately adjacent to the disturbed areas as a result of acid generation. It <br /> is well known that in acid generating environments,the grasses in the areas around the toes of acid <br /> generating waste rock piles commonly show biological stressing. On the rock piles that were inspected <br /> on the north side of Mineral Hill, no evidence was found of any migration of low pH waters that <br /> negatively affected the adjacent flora. <br /> During that inspection, Braun found a shaft that contained standing water to within 12 feet of the shaft <br /> collar. That shaft had been sunk into the same mineralized structure in which the lower tunnel had <br /> been driven. Braun personnel collected a water sample from that shaft and tested the collected sample <br /> for pH. That test showed the water to have a pH of 6.1. This value is a relatively neutral number, not <br /> significantly lower than values found in the local creeks. The visual inspection of the shaft found no <br /> evidence of acid water conditions. Careful inspection of the galvanized steel shaft liner with its integral <br /> steel ladder found both of them to be in good condition with no signs of significant acid water corrosion. <br /> 3 <br />