2011-02-04_PERMIT FILE - P2011002

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The drilling depth is described as 450 feet, and the NOI states that the holes are anticipated to be dry. Given what is generally known about the hydrology in this area, from existing underground mine workings, wells and creeks, this office feels it is highly likely that groundwater will be encountered at depths of 150 to 300 feet, depending on which drill pad it is drilled from. There may be both alluvial and bedrock aquifers intercepted. Please be aware that mixing water between aquifers is to be avoided, and that bore hole sealing procedures must be promptly and thoroughly performed. Please clarify whether drilling will proceed deeper after an aquifer is penetrated. 6. The site description includes reference to two closed mine portals and the associated old waste dumps, near drill pads number 2 and 4. Aside from committing to not reopen the portals, please state whether there will be any other effect to the dumps or other pre-existing mine feature. The Division cautions the applicant to avoid or minimize disturbance to the old dumps as this could liberate mineralization to the soil, water or downhill areas in general. 7. There is a set of photographs included in the NOI packet, but they are not labeled. The knowledge this office has of the area allows us to make the following assessments of the photographs: One photograph shows drill site 1 fairly clearly. Another photograph shows site 4 clearly. One photograph is an overview of the hillside in the general vicinity of site 2, though it is not shown closely or clearly. There is no photograph of site 3. One photograph in the group was taken looking south from CME #19 and shows the grassy saddle and hilltop in CME #14, which are areas that will not be affected at all according to the narrative and maps. Please confirm these descriptions. If you have a photograph of site 3 please provide it. 8. The area to be affected is described to be 2.9 acres. This office estimates that the four drill pads and upgraded roads, plus the footprints of the associated cut and fill, will disturb less than one acre. Is the remainder of the affected area (over two acres, and as shown by cross-hatching on map C-4) simply what is potentially affected by runoff or sediment? Will there be any reclamation to be performed on the remainder area? Please verify. 9. Map C-4 (Exhibit I) includes the reclamation plan and a seed mix. Is this the seed mix required and/or approved by the US Forest Service? 10. The seed mix contains the seeding rate for each species in pounds of seed per acre. Please state whether this seeding rate is expressed in terms of pounds of "pure live seed" (PLS) per acre, or whether the rates simply reflect bulk seeding rates. 11. The fertilizer rate (300 pounds per acre) of 18-46-0 appears too high. This office recommends that no more than 200 pounds per acre be used, unless the US Forest Service requires it. Please confirm what fertilizer rate will be used, and why. There was no financial warranty (bond) included with the NOI, which is technically a deficiency, but is presently understood by all that the Division will calculate the appropriate bond amount after the other deficiencies and technical issues have been addressed. Please provide complete responses to the items listed above, as this will help the Division prepare a good bond estimate. The figures will be sent to the applicant soon after receiving adequate responses. , Please submit all response materials (text and/or maps) by providing two sets of hard copies. No CD is required. These materials may be sent directly to me at the Durango field office: 691 CR 233, Room A-2, Durango, CO 81301. These items must be received here within 60 days of the date of this letter or the NOI maybe terminated (pursuant to Rule 5.1.3(c)). Additionally, if you have received any pertinent correspondence from the US Forest Service, please forward copies to the Division.