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<br /> <br />ready for bond release, the upper half of the existing haul road will be removed, although an <br />unpaved access road will be left for maintenance of ponds. Paved roadway sections that are <br />conveying stormflows into sediment ponds will be left intact to minimize downstream sediment <br />loading. <br />9. The applicant acknowledges the Division's request for consideration of their recommended <br />hC seed mix. Please note that on page 14 and IS of the permit application, a specific set:d mixture <br />° and rate is included. The seed mix listed includes all species in the Division list plus other <br />species found on site and the overall rate is 25% higher. The relative rates of species in the <br />overall mix will follow the Division's recommendation, but should not be limited to ~:he species <br />as listed. <br />k 10. The mine operator is committed to yearly maintenance of sediment pond structures or as <br />° needed to insure the proper operation of the ponds as effective storm run-off control :structures. <br />I I. The applicant will contact the Water Quality Control Division of the Colorado Department <br />of Health and forward to the Division that correspondence pertaining to the review of the <br />stormwater management plan and the WQCD determination of discharge permit requirements. <br />12. The final design change for Sediment Pond # I is to enlarge the storage capacity of the pond <br />ak including the water impermeable liner from the planned 50' x 100' to 50' x 200' to insure proper <br />operation of the diversion pond with minimal maintenance requirements. Otherwise, all other <br />design features are intact as shown in the accompanying engineering drawings, titled SWMP <br />DETAILS. <br />ok 13. The applicant does not agree that perforated pipe drop inlets will be more effecti~ie than the <br />design as proposed due to the inefficiency of the slotted pipes when subject to large volume <br />loading. The perforated pipes area maintenance problem which does not negate the need to <br />handle water discharge through a wide (25') rip-rap protected spillway and through a properly <br />constructed ditch to the next sediment pond entrance. Due to the dimensional aspect. of the <br />sediment pond system construction, direct percolation into the very course rock and gravel <br />alluvium found at this location will be adequate to handle events up to 100 year. Annual <br />sediment pond maintenance will insure that fines do not build up in the bottom of the sediment <br />ponds and decrease percolation rates over time. The SWMP Details drawing shows the basic <br />design of the sediment ponds spillways from #5 to #6 to #7 and possible discharge location out <br />of #7. The applicant agrees to install a gates emergency discharge at the exit of pond #7. <br />14. Please refer to the stotmwater plan narrative and SWMP titled "typical spillway details <br />ok pond(s) 5,6,7, that show all transfer points of stotmflows from Pond #5 to #6 and #? as transfer <br />aprons conswcted of a geotextile liner(keyed) with a sand, gravel and finally rip-rap liner up to <br />12" to slowly release and direct pond flows to the next sediment pond structure. These plans <br />specifically address Division concerns as noted. <br />