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The response materials included a drawing showing two such bulkheads. Please clarify whether there will be two tailings <br />cells to be filled, or whether the lower one nearer the mill is a secondary back-up. The lower bulkhead must be <br />constructed to be as strong as the upper one. <br />The sediment ponds are an integral part of the operation, and will also provide added stability to the reclaimed site. Their <br />location and area can be determined from the site maps, but not their depths or volumes. Please provide the depths, and <br />individual or combined volumes. <br />The edge of the proposed waste rock storage areas that are near Sneffels Creek are of concern to this office, since <br />inadvertent mishaps in materials handling, or the occasional snowslide, may cause waste rock to slough down the bank. <br />Please be reminded that the permit boundary is halfway down that bank, and that sloughing, erosion or loss of dump <br />material, involving excursions outside the permitted area boundary, may be a possible violation. It is therefore suggested, <br />in order to maximize the storage areas, yet still provide a level of safety and stability during the many occasions to place <br />and remove waste rock, that a physical barricade such as jersey barriers, should be considered in those locations. Please <br />comment on the use of this type of barricade or other means to provide dump slope stability. <br />Exhibit D - Reclamation Plan (Rule 6.3.4) <br />The reclamation plan now consists of cut and fill, placement and grading of clean waste rock, to attain 3:1 slopes <br />throughout much of the site. Portals and structures will remain, though they will be secured. Milling equipment, if left <br />onsite will be placed underground. All fluids and hydrocarbons associated with mining and milling will be removed. <br />The milling circuits will be emptied and cleaned. Tailings will be placed in approved locations. Debris and equipment <br />will be removed. No topsoil will be replaced, and there is no revegetation required. Equipment to perform the required <br />reclamation is anticipated to include a medium tracked excavator, medium bulldozer, and medium loader. <br />Please note that bonds may be adjusted up or down, during the life of an operation, depending on the level of disturbance <br />and the details of the reclamation plan. One detail that can affect the bond amount is a description of when certain areas <br />of the site will be backfilled with waste rock, or specific amounts of waste rock that will be placed, toward attaining final <br />reclamation surfaces. There are nearly 3,500 net cubic yards needed, and as more of that is placed in areas which will not <br />be redisturbed, the lower the bond amount. Please comment on whether you wish for this to be considered as part of the <br />current bond calculation. <br />Exhibit E - Mining and Reclamation Plan Maps (Rule 6.3.5) <br />Thank you for the updated mining and reclamation maps, and the signed and dated drawings. They appear to meet all <br />requirements. One item of note on the reclamation map was the need to maintain structures to control surface drainage, <br />especially stormwater and upland runon. You do not need to revise this map to show that these features are retained, but <br />please state that reclamation grading and backfilling will account for and control future drainage. (The specific features <br />of note include the drainageway on the SE end of the site and on the right of the mill portal, plus where the flows are <br />directed onsite.) <br />Water and Rock Sampling <br />This office is satisfied with the proposed parameters, schedule, and reporting of sampling and analysis that you provided <br />in your responses. These will become part of the sampling and reporting requirements. <br />Adequacy Responses <br />Please provide responses to all adequacy issues identified in this review letter. Submittals should include two copies of <br />all responses, especially oversize maps. All response materials may be submitted directly to me at the Durango field <br />office (see address below).