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when considering the initial cut into a new area, the advancing highwall could be no <br /> shorter than 150 feet in order for the left and right highwalls to be backfilled to 3H:1 V as <br /> the highwall advances (assuming a 25 foot height—leading to 75 feet of backfill on either <br /> side). This would limit the length of unbackfilled left and right highwalls to 25 feet each to <br /> keep the length of highwall to 200 feet. Furthermore, this configuration would not leave <br /> any width between the backfilled left and right highwalls for equipment access. <br /> Secondly, this approach would likely require nearly constant moving of previously <br /> replaced backfill material as the highwall advances in the direction ofpreviously backfill <br /> left and/or right highwalls. Thus making the approach economically infeasible. Please <br /> reconsider this approach and provide a more practical highwall length limit. As this is a <br /> critical component of the financial warranty estimate, the Division will require a <br /> commitment for the Permittee to limit the highwall length and if found to exceed this limit <br /> during a future inspection, a surety increase will be issued. <br /> Given the light production of this pit, the operator wishes to minimize the bonding requirements. <br /> They are well aware of the limitations this imposes on the operation. <br /> 7. Revegetation plan: Drilled vs broadcast seeding. This first paragraph on p. E-2 indicates <br /> seed drills can be used on both the flat and reclaimed slopes, then states broadcast <br /> seeding will be used "where reclaimed perimeter slopes do not allow drilling." The <br /> Division doubles the seed rate for broadcast seeding, which impacts the bond estimate. <br /> Please explain where the proposed 3H.•I V reclaimed slopes will be too steep for seed drill <br /> application. <br /> Broadcast seeding will be used on topsoil stockpiles,which can be too steep for safe drill <br /> seeding. All final reclamation slopes will be shallow enough for drill seeding. <br /> 8. Seed mixes: Section 3 on page E-2 indicates different seed mixes will be used on the slopes <br /> and pit floor. The provided seed mix on page E-3 appears to be for the slopes only and is <br /> completely different than what was approved by the Division for the original permit <br /> application and appears light with respect to the estimated seeds per square foot(roughly <br /> 50). In order to estimate a bond, the Division also requires a seed mix for the pit floor <br /> (irrigated pasture). <br /> a. Please explain why the change in seed mix. It is very light on grasses. The Division <br /> would expect more grasses for a rangeland post-mine land use. Was the new one <br /> provided as a recommendation from the Fremont Conservation District? <br /> b. Please provide a seed mix for the irrigated pasture. <br /> The seed mix from the existing application has been restored. All references to irrigated pasture <br /> have been removed from the permit. See the revised Exhibit E. <br /> 9. Post-Reclamation site drainage: Rule 6.4.5(2)(c) requires the Applicant to explain how the <br /> reclamation plan meets the applicable requirements of Rule 3.1. Rules <br /> 3.1.5(1).Appropriate final grading topography and Rule 3.1.6(1), disturbance to the <br /> prevailing hydrologic balance do not appear to be adequately addressed. The proximity of <br /> highwalls shown on the referenced Map F-1 which extend below the thalweg of the <br /> adjacent ephemeral drainage and which are in the 100 year floodplain is likely to have an <br /> Yevoli Cobblestone CN-01 3 .,,.... ri <br />