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are required when a pond contains water. It is very difficult to find the low and high <br />points under water from one year to the next. <br />Based on the up drainage watershed characteristics, one 10-year, 24-hour precipitation <br />event would generate 0.05 ac-ft of sediment using M.U.S. L. E. <br />The equivalent of the sediment generated from approximately 110 10-year, 24-hour <br />precipitation events could be stored beneath the principal spillway elevation based on the <br />1986 sediment survey. This is a conservative amount of sediment storage; therefore, no <br />remedial sediment clean-out work is scheduled for the five-year permit term at this time. <br />Sedimentation Pond 004. The design infcrmati on and calculations for this pond were <br />submitted in the Seneca II Permit Renewal Application August 27, 1986 and subsequently <br />approved by CMLRD. On September 8, 1986, Sedimentation Pond 004 was resurveyed as part of <br />Se neca's 1986 annual sediment survey. The survey information was utilized to develop a <br />computer-generated contour map. This data was used to calculate the remaining sediment <br />storage beneath the principal spillway. <br />• The following table shows a comparison of the 1985 and the September 8, 1986 volume <br />calculations. <br />1985 September 8, 1986 <br />Capacity Cumulative Capacity Capacity Cumulative Capacity <br />Elevation (Ac-Ft) (AC-Ft) (Ac-Ft) (AC-Ft) <br />6936.0 <br />O.D84 0.05 0.050 <br />6937.0 <br />6938.0 <br />6939.0 <br />6940.0 <br />r1 <br />LJ <br />0.199 0.25 0.141 0.1 <br />69 0.331 0. <br />729 1.42 0.623 1. <br />1.039 2.46 0.883 2.03 <br />7-19A-3 <br />