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<br />Comment 6. Please indicate if [he maximum disturbance listed (32.2 acres) includes disturbance <br />from Phase I that requires backfilling. If not, will the Phase I area be completely backfilled and <br />revegetated at the time of maximum disturbance? <br />• The estimated area of maximum disturbance outlined in Exhibit D does not include the <br />Phase I area. It is intended that the Phase I area will be used as a siltation pond for Phase <br />II operations and continued operations at other applicant permitted facilities (i.e. permit <br />M-78-052). Portions of the Phase I area not used as a siltation pond will be backfilled <br />with overburden material. For the areas not backfilled, fines that are generated during <br />material washing operations will be settled from process water are anticipated to produce <br />the majority of backfill as well as the medium for the constructed wetlands. Therefore, <br />the Phase I area will not be completely reclaimed during the period of estimated <br />maximum disturbance. A revised table for the area of maximum disturbance is enclosed <br />in Attachment E. <br />Comment 7. Please verify if the applicant plans to install any stormwater drainage structures <br />within or immediately adjacent to the First Creek floodway channel. If so, please provide a <br />representative cross-sectional diagram of such features. <br />• It is anticipated that grading of the site will direct all stormwater that contacts lands <br />disturbed by the proposed mining operation into the Phase I or Phase II pits. Stormwater <br />from the site will not be routed to the First Creek floodway channel and the applicant <br />does not plan to install any stormwater drainage structures within or immediately <br />adjacent to the floodway channel. In pursuit of the applicable Floodplain Use Permit <br />required by Adams County, the applicant is continuing discussions with the Urban <br />Drainage & Flood Control District to address [heir concerns. <br />Corrunent 8. Provide the Division with A) a copy of the SEO's lerier approving the proposed <br />liner design and a copy of the design and specifications for inclusion into [he applicant's <br />application prior to the Division's recommendation date; B) a commitment to stay at least two <br />feet above the high water ground water level; C) a financial warranty adequate to cover the cost <br />of backfilling the pit; D) a letter from the SEO stating that the applicant has satisfied the SEO <br />requirements for a well permit and an augmentation plan or substitute supply plan for the <br />proposed exposure of ground water and evaporative loss; or E) a representative cross sectional <br />design of the liner construction, design standards, and a narrative of construction methods to be <br />used to construct the liner. <br />A representative cross-sectional diagram of an SEO approved liner, design standards, and <br />construction methods are enclosed in Attachment F. A similar, if not identical design <br />will be constructed at the proposed Tanabe site. This design is also being used at the <br />permitted facility (M-78-052) directly west of the proposed site. The installed liner has <br />met all SEO performance standards. <br />Comment 9. Indicate the volume of overburden necessary to complete Phase I reclamation at the <br />time of maximum disturbance as indicated in the Mining Plan-Exhibit D. <br />• As discussed in the response to Comment 6, the settling of fines is anticipated to produce <br />the majority of backfill for the Phase I pit. The total quantity of backfill required will <br />Page 3 <br />