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APPENDIX 2 — TAILINGS SPLP TESTS <br />Ouray Silver Mine has taken samples of the tails produced by their onsite mill periodically since <br />May 2014. These samples have been subjected to Synthetic Leaching Precipitation Protocol <br />(SPLP) tests as defined by the Environmental Protection Agency (EPA) to determine what, if <br />any, metals might be mobile in the tailings, and therefore in danger of leaching into the area <br />groundwater once the tailings have been placed. <br />Based on the SPLP results shown in Table 1, the mill has successfully produced tailings with no <br />mobile metals on the last three rounds of testing. It was determined by this testing that while a <br />pH of 9 would be sufficient to prevent the mobilization of metals such as zinc, silver, ET. Al., a <br />higher pH would be an extra safe guard against said metals mobilization. Therefore, Ouray Silver <br />Mine revised the reclamation permit to allow for the placement of tailings with a pH of up to <br />10.5. <br />As with any tailings embankment, the groundwater wells downstream of the tailings piles are the <br />final arbiter of tailing chemistry. These wells at the Ouray Silver Mine are sampled quarterly, <br />with the results provided to DRMS. Also, when the mine is in production, tailings from the mill <br />are sampled quarterly for SPLP testing, the results of which are also reported to DRMS. <br />