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the ponds the finished depth would continue to average 15 feet. To provide for excavation <br />variability and pond freeboard storage, surface area calculations assumed a maximum storage <br />depth of 12 feet. All hydraulic calculations are based upon surface elevation data provided by <br />King Surveyors, Inc. <br />2.4 Hydraulic and Hydrologic Constraints <br />Constraints on the hydraulic design of the reclamation plan can be grouped into three <br />categories; wetland construction, pond construction, and pond system operation. For each of <br />these three categories elevation data and depth of mining assumptions are important. Data and <br />recommendations concerning wetland construction were obtained from Habitat Management, <br />Inc. (Habitat) and the 404 permit. The June 9, 2003 and October 2, 2003 Reports by Habitat are <br />included as Appendix B and a copy of the 404 permit is included as Appendix C. Constraints <br />relating to the pond construction are based upon reports made by Earth Engineering Consultants <br />'- (EEC). The June 11, 2003 report from EEC is included as Appendix D. The operation of the <br />pond system was developed based upon data generated for the augmentation plan prepared by <br />this office <br />The wetlands to be constructed as part of the reclamation plan fall into two categories as <br />defined by the 404 permit. Wetlands are areas having a standing water depth of 0 ft. to 3 feet. <br />Wet meadows, the; second category, are areas where the depth to the water table is 0 to 6 inches. <br />An additional requirement of the 404 permit is 14.9 acres of open water. The compensatory <br />wetlands requirement in fhe origina1404 permit was 85.6 acres of wetland and 43.9 acres of wet <br />meadow, which totals to 129.5 acres. The original delineation of wetlands displaced by the <br />mining operation was 78.4 acres. According to the preliminary Habitat report dated October 2, <br />2003 the 404 permit can be amended to reduce the required compensatory wetlands to <br />78.4 acres. The COE will only require a replacement ratio of 1:1 for wetlands displaced. Based <br />upon the requirements of the original 404 permit 2/3 of the wetlands replaced were to be 0 to 3 <br />feet wetlands, and 1/3 were to be wet meadow. Applying the same ratios to the 78.4 acres of <br />required wetlands results in 51.7 acres of wetlands and 26.7 acres of wet meadow. Included in <br />the original delineation for the 404 permit was 14.9 acres of open water. The reclamation layout <br />proceeded under the assumption that the COE will maintain this requirement in the amended <br />permit. Table 2.1 summarizes the compensatory wetlands requirements for the Timnath Pit <br />reclamation plan under an amended, approved permit. <br />T:IOPEMCodkc011codkc0l firm( reporr.doc S ANdER50N CONSULTING ENGINEERS, ANC. <br />