Laserfiche WebLink
9.69 feet (Elev. 6577.69). Tables 6 and 7 contain the batch input <br />s data file and the ouput file from the SED= II analysis, <br />respectively. This peak stage (9.69 ft.) indicates that no flow <br />would occur through the emergency spillway (stage 12.0). The <br />principal spillway is of sufficient size to handle the discharge from <br />the 25 -year, 24 -hour storm event at a peak discharge rate of 0.42 <br />cfs. The existing emergency spillway will act as a safety factor for <br />Pond 003 and is a trapezoidal channel with 3H:1V side slopes and <br />bottom width of 10 ft. Table 8 contains a rating curve computation <br />for this spillway which shows it can conservatively handle the peak <br />discharges. <br />The Northwest Impoundment (No. 003) will remain as a permanent <br />incised indent after mining to compliment the postmine land use. <br />The pond will provide a dependable source of water for livestock and <br />wildlife. Appendix 7 -10, Tab 7, the Pond Abandonment Plan section <br />and Appendix 13 -2 of Table 13, and the Proposed Decision and Findings <br />of Compliance Document for the second renewal of Seneca II Mine <br />Permit C -80 -005 (11/20/92) contain discussions pertaining to the <br />permanence of this facility. The proposed permanent post nine <br />Northwest Impoundment (No. 003) is shown on Exhibit 7 -11A. <br />7 -6b-6 Revised 12 /10/92 <br />