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can last for days in the case of spring thaw and 2 -18 hours in the case of a significant thundershower, <br />which actually happen frequently from May through October. In comparing this to the mine related <br />discharge that occurred on October 24, 2014, it was comparable to a typical significant thundershower. <br />Assuming that the event started at 2 AM in the morning on the 24th, and ended at 8 PM, this is a total of <br />18 hours. Since the stream is used to this type of water, it is extremely unlikely that the higher sediment <br />load for that time interval caused any problems to insects, fish or other animals that use the stream. It <br />also did not affect water used by Ouray or any other users downstream. <br />Due to the nature of the andesite rock and the source of the sediment laden discharge, it is not possible <br />that this event caused any other contamination of the water leaving the mine. The water basically had a <br />reddish clay that was picked up by the water trickling through the muck from the raise bore drilling <br />process. The water then left the mine through the ditch in the main tunnel. The raise bore does not use <br />any chemicals that would contaminate the water and the sediment was visually observed coming from <br />water trickling down the sides of the raise bore into the crushed andesite at the bottom of the hole. <br />The mine operation has received a discharge permit for the mine water leaving the mine and entering <br />Sneffels Creek. This permit is not yet active since it only goes into effect after the mine water pond and <br />monitoring equipment is completed. This work will be completed by December 15, 2014 and the permit <br />will go into effect at that time. Therefore, no actual violation of the permit occurred although the high <br />sediment concentration of the discharge for the approximate 18 hour interval would have exceeded the <br />limits of the permit. <br />All water sample results are included in Appendix A. <br />Page 14 of 17 <br />