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<br />depend on final constructed wetland design, but would not likely exceed one-half million <br />cubic yards of material. It is anticipated that at least half (or potentially more) of the total <br />backfill requirement will be composed of settled fines from use as a siltation pond. <br />Comment 10. Indicate on the Mining Plan Map the location of any permanent sediment and <br />siltation structures that will be installed prior to or during the mining phase of the operation. <br />• As stated in the response to Comment 7, it is anticipated that the site grading will direct <br />all stormwater that contacts lands disturbed by the proposed mining operation into the <br />Phase 1 or Phase II pits. Therefore, the installation of sediment or siltation control <br />structures is not anticipated at this time. If the installation of these structures is <br />necessary, typical control structures will be used. Diagrams of representative <br />sedimentation and siltation control structures are enclosed in Attachment G. The only <br />sediment or siltation structure to be used for wetland mitigation (referred to in Exhibit E, <br />Reclamation Plan) is the Phase I pit. During operations the Phase 1 pit will be used as a <br />siltation pond. After mining operations, the backfilled pit area will remain as created <br />wetlands for mitigation from other properties or banking. <br />Comment 1 1. The Division recommends that the applicant apply a topsoil cover of at least 12 to <br />18 inches for shoreline and surrounding areas that are to be revegetated with a grass mix. Please <br />comment. <br />• Once the stockpiled topsoil has been used to cover all disturbed areas to a depth of 4 to 6 <br />inches, any excess topsoil remaining on-site will be used to achieve a shoreline and <br />surrounding area depth of 12 to 18 inches in conformance with the reclaimed pit as <br />proposed in Attachment F. <br />Comment l2. Provide a revegetation plan for the created wetlands and an associated cost for <br />establishing such vegetation. As an alternative, the applicant may elect to submit a technical <br />revision to the application with such information following issuance of the required 404 permit <br />from the U.S. Army Corp of Engineers. <br />• A U.S. Army Corps of Engineers 404 permit is not required for this site. Jurisdictional <br />wetlands are not present. Based on past experiences by this operator (applicant) at <br />numerous locations, native species tend to naturally revegetate areas proposed for final <br />wetland vegetation. If, at the time of final reclamation, a suitable plant cover is not <br />established, a revegetation plan and cost estimate for the Phase I created wetland area <br />will be submitted as a technical revision to the application. <br />Comment 13. Provide an analysis of the hydrologic impacts that might be expected to <br />surzounding property owners and well owners following completion of the lined 40-acre water <br />storage reservoir. (What, if any, is the lateral and vertical extent of the projected upgradient <br />mounding affect and the downgradient shadowing affect?) <br />• Based on the hydrologic evaluation of the alluvial aquifer presented in Attachment P, the <br />applicant does not anticipate mounding or shadowing impacts from the lined water <br />storage reservoir. The evaluation indicates that the hydrologic gradient in the area of the <br />proposed Tanabe site is low, approximately 0.006 ft/ft, allowing for equilibration of the <br />Page 4 <br />