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manual, the 0.5 ft/sec. peak particle vibration velocity, will protect, even fragile buildings and structures from <br />probable adverse impacts from vibration. If the operator agrees to not exceed, the selected peak particle <br />velocity, a pre- blast survey might not be needed. However, as suggested in item A, the operator should attempt <br />to contact the property owners. <br />c) The operator must record the location of the blast monitors, each time a blast is conducted. The PPV that is <br />generated from each blasting event must not exceed 0.5 ft/sec, or the PPV approved by the Division based on <br />the analysis discussed above demonstrating that such PPV will not adversely affect offsite structures. The results <br />of the peak particle velocity that is generated from each blasting event must be recorded and verified. All the <br />recorded data must be available upon request by the Division. Please submit a blast monitoring plan and result <br />reporting plan. The Division will require that a blast monitoring report be included in the annual reclamation <br />report once the site is permitted. <br />9.) What will be the average slope measure of the 20 to 30 foot mine bench? What will be the maximum length of the <br />mine face during a mining phase? <br />10.) Please provide specifications and designs for the sediment control berm. A letter submitted with Exhibit I; Soil <br />information from Don Sanchez to Jim Sperry indicated the sediment basin would be difficult to construct with the <br />gravely soil material and would be highly erosive. Please address this issue. <br />11.), Please provide specifications and designs of the storm catchments berms depicted within various locations of the <br />drainage. <br />12.) It appears storm water will be impounded at the sediment control berm. Please commit to obtaining a temporary <br />substitute water supply plan or appropriate permit from the Colorado Division of Water Resources to augment the <br />evaporative loss generated by the impounded storm water. <br />13.) Will any secondary or incidental commodities be mined? <br />6.4.5 EXHIBIT E - Reclamation Plan <br />14.) The proposed 3 to 6 inches of topsoil to be spread does not appear to reflect the soil conditions at the site. The <br />NRCS soils report and reclamation recommendations indicate there should be sufficient topsoil on the site to spread at <br />least 6 inches of growth medium over the reclaimed area. Every effort will need to be made to salvage as much native <br />topsoil as possible. Please commit to spreading at least 6-10 inches of growth medium over the reclaimed land. <br />15.) If overburden is stripped in advance of the mining operation, what approximate depth will it be replaced? <br />16.) At what point during the mining operation will steps be taken to create the 3:1 horizontal to vertical ratio pit <br />slopes? Will the mining face reach a certain length when grading will take place? The Operator may want to consider <br />grading the mine face to a 3:1 ratio as mining proceeds to minimize the amount of the required reclamation bond. -, --- - <br />17.) Once the mine face is blasted to create the final material necessary to grade the pit slopes to the required 3:1 ratio, <br />how will this material be placed and compacted to ensure the slope will be stable during final reclamation and will be <br />able to hold the topsoil in place for final revegetation? <br />18.) If the pit floor is flat as it is depicted on the reclamation plan map, how will the site drain properly? <br />19.) Will the sediment control berm be left in place after reclamation? If so, what purpose will it serve? With the berm <br />left in place, given the likely hood of impounded storm water creating a pond, the Operator will have to obtain <br />permanent plan of augmentation. <br />3 1 P a g e