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Response to Adequacy Review Comments Coulson Eacavatiug Company, Inc. -Bonner Gravel Pit c) The lmer will be designed to overcome the hydrostatic pressure exerted against the liner wall from groundwater, even with the absence of water in the reservoir. Constructing the liner with the correct thickness, in addition to the pressure on the water table from the liner substrate, will accomplish this objective. Seepage into the reclaimed area is not considered an issue, due to the fact that the area will be used for water storage purposes. d) The list of items (i-viii) have been incorporated into Exhibit E, "Liner Design / Specifications". e) Exhibit E, Appendix I "Quality Assurance Procedure" has been updated to include all information requested (i-v). f) Other pit liner issues: i) A commitment from Coulson Excavating Company, Inc. is included with the modified exhibits. ii) A final wnstruction report and certification for the pit liner will be provided to the Division of Minerals and Geology. This is also stated in detail in Exhibit E, Appendix I, "Quality Assurance Procedure" iii) Liner performance testing will be conducted according to the given specifications. This is also stated in detail in Exhibit E, Appendix 1, "Quality Assurance Procedure". Other Comments: A trapezoidal berm measuring 49.5 ft wide at the base, 10 ft wide at the top, and approximately 8 ft-16ft in height will be constructed along the permit boundary (at the edge of the pit) following the grading and wmpaction of the liner substrate. The berm will be lined with weathered Pierre shale along with the pit slopes. The slopes of the pit and berm will be contiguous, and the entire lined azea will be utilized as a water reservoir. Please see Exhibit E for details. The berm will be under the jurisdiction of the Office of the State Engineer, due to its size. Approval from The Office of the State Engineers office will be in place prior to construction of the dam.