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<br />You state that excess materials ntay be backfilled, presumably into the ponds at Cheir margins. Please note that <br />material backfilled into a pit below water line, with no benefit of compacting, should not be considered as stable as <br />unmined material lying below the water line. Therefore, without providing information distinguishing exactly what <br />types of materials may be backfilled nor an engineering evaluation of the potential for slope failure of these <br />materials, the Division cannot approve a slope gradient steeper than 3: 1, for backfilled, submerged materials. <br />Additionally, how will any backfilling activity be carried out, so that maxintunt slopes are not exceeded? Please <br />comment. (Please note that if backfilling is to occur on drvland or strictly on the pit floor, these issues are moot.) <br />The existing landform is fairly level, which indicates thaC [he resulting pond slope lengths ma}• be fairl}• uniform <br />around the margins (a detail to be utilized in our reclamation cost estimate). However, the depth to groundwater is <br />not specified in dte application, nor is the seasonal variation in water level. Please clarify these points. <br />The topsoil will be stripped prior to excavating the ponds. The amounts of topsoil salvaged need only be sufficient <br />to "plate' the inslopes down to the water level and other "non-road" areas for reclamation. Topsoil salv'ged for <br />this purpose is to be windrowed along some of the pond margins. Do your maps show all of the topsoil stockpile <br />areas? Please 6e aware that if there are final pond margins along which no topsoil has been stockpiled, the bond <br />amount for replacement will be higher, since it will involve a haul cost in addition to a cost for simply pushing it a <br />short distance. Please comment. <br />What will be the seed mix and application rate for temporary protection of topsoil stockpiles? <br />(Please note that sufficient topsoil must be retained onsi[e for all of the total dryland areas which currently require <br />topsoil replacement at an}• time during the operation. Therefore, the stockpiled amount may be reduced as the <br />currently-active pond groves. Likewise, the respective costs for the revegetation aspect of the reclamation plan will <br />probably vary as the pond size changes.) <br />Though it is not stated specifically in this exhibit, the timetable shown on the mining plan map indicates that t}te <br />four ponds ("cells") will be excavated one at a time, with no overlap in years noted. Please describe to what extent <br />reclamation will be accomplished, or finished, at one pond before disturbance begins at the next one. <br />The utility corridor crosses the site between the area to be excavated and the stockpile and rail spur area. The <br />mining plan map states that a "non-mining" buffer will be maintained in the utility location, though it is clear that <br />hauling operations must cross that buffer. This buffer is shown to be partly outside the permitted area boundary, <br />and partly inside the boundary. Please describe any activities you plan to undertake to mitigate possible damage to <br />buried utilities and to overhead lines and poles, pertaining to haul road and/or rail spur construction and use. I will <br />explore the need for notarized damage agreements under Exhibit S below. <br />Similar questions exist for damage mitigation activities for impacts to roads and ditches on the property, which are <br />owned by the landowner/operator, or other entity, and for stream crossings on the property. Will there be filled or <br />culverted drainagevvays under haul roads or the rail spur? Please clarify. <br />It appears as though you have submitted }•our plan (to excavate ponds and build a rail spur) to the county for <br />obtaining a conditional use permit. Has the county approved the building of the rail spur? If so, it is presumed [hat <br />the county has reviewed a plan of sufficient detail to ensure that the spur will serve the purposes of conveying <br />aggregate to the rail line. Likewise, since your reclamation plan states that the spur will remain, it is presumed that <br />[he county approves of this post-mining use. Is this the case? Please comment. <br />You plan to crush, screen and wash aggregate, all of which are to occur in the area shown as central to the four <br />cells. This processing area will be reduced to about 4.5 acres as the cells gradually encroach and surround it. Will <br />there be sufficient space available for haul roads, mining equipment, processing equipment, product stockpiles, and <br />possibly topsoil stockpiles, in this area? Will there be any berming of roads or pads for stormwater or water quality <br />reasons'? Please comment. <br />