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The placement of milled sub-grade ore materials underground may fall under the authority of the EPA, and may require <br />an underground injection permit. Please state whether you have inquired about the need for such a permit, and whether <br />EPA has placed any restrictions on the proposed plans. <br />During mining and milling the need for the sediment pond(s) is obvious, since it functions to settle out suspended solids. <br />However, there are numerous references in the discussion about the sediment pond reducing or eliminating dissolved <br />solids. Properly designed, the sediment ponds will accept the total discharge, settle out the suspended sediments, and <br />allow clarified water to pass to Sneffels Creek. There is no active water treatment occurring, and no special characteristic <br />of the rock comprising the sediment ponds. It is assumed that all dissolved solids that enter the ponds remain dissolved <br />and therefore leave with the effluent. Please comment. <br />The surface map being used in the application (Figure E.1) is a modified version of Steve Fearn's map, which he signed <br />on 3/18/08. Its original version included: a sediment pond measuring 23 ft x 50 ft, set away from the existing roadway, <br />with a buried discharge pipe leading to the slope above the creek, where the discharge reports to. The changes that were <br />made to the map that was submitted under this application include eliminating the buried pipeline, no labeling of the <br />discharge point, and showing a series of two sediment pond cells which do not appear to be depicted in the correct <br />location. (Note: During the May 27, 2010 inspection, three cells were observed, with the majority of the area they <br />occupied appearing to be located in the "pre-law roads" area. The lowest cell was shallow enough to be crossed by <br />vehicle, with no culvert or apparent consideration for the increase in turbidity every time equipment or vehicle crosses it <br />to access the ore pad. It is suspected that where the water goes underground is the remnant flow path from where the <br />former sediment pond was recently filled in with waste rock. Onsite personnel during the inspection stated that the <br />sediment pond water simply "infiltrated" and stated they knew of no connection between infiltrated water and the 6-inch <br />PVC pipe that was observed discharging water to Sneffels Creek. Given these discrepancies in the map and observed <br />facilities, please provide a better description of the sediment ponds and the discharge pipe, and show them on the map. <br />Please provide a description of the water sampling locations, as well as show them on a map. <br />Please provide information about the frequency of the "routine" sampling of the sub-grade ore. What parameters or <br />analytes will be included? Will the analyses be done onsite or sent to a lab? Presuming that you will be required to send <br />the Division copies of the analyses, under what type of schedule do you propose that the analyses be sent to the Division? <br />Ore that has been processed will be placed on the concrete ore pad for hauling or sacking. Please describe whether the <br />ore has had sufficient opportunity to decant (where, how, for how long or until what moisture content). The ore pad is <br />concrete, but it is not bermed and provides little containment. Please provide description of how loose ore or sacked ore <br />can be adequately handled or contained, and how loss of ore or leaching of minerals due to precipitation will be avoided. <br />The waste rock areas that are currently affected and which may become affected by future storage of waste rock are very <br />limited in the permitted area. Additional rock will likely be placed by dumping it on the pad, as all current waste rock has <br />been, by mucker or loader. Such placement does not assure compaction or stable side slope gradients. The edge of the <br />waste dump currently in the proximity of Sneffels Creek is of concern to this office, given to the potential for failure due <br />to instability or inadvertent loss from snowslide. As more waste rock is dumped, the dump slopes will continue to <br />become higher, but the mining plan provides no discussion about dump slope gradients, stability, setbacks, or material <br />placement. Also, there is no estimate given for the amount of waste rock that may potentially be placed, yet still <br />providing for onsite stability and reasonable future land use for general agriculture. (The operator is reminded that <br />sloughing, erosion or loss of dump material, involving excursions outside the permitted area boundary, may be a possible <br />violation.) Please provide information about the waste rock and dump slopes, regarding the issues identified above.