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<br /> <br />Elevation <br />Capacity <br />(Ac-Ft) 1965 <br />Cumulative Capacity <br />(Ac-Ft) September <br />Capacity <br />(Ac-Ft) 8, 1986 <br />Cumulative Capacity <br />(Ac-Ft) <br /> 6941.0 <br /> 1.331 3.79 1.114 3.14 <br /> 6942.0 <br /> 1.615 5.41 1.372 4.51 <br /> 6943.0 <br /> 1.914 7.32 1.658 6.17 <br /> 6944.0 <br /> 2.634 9.96 2.494 8.67 <br /> 6945.2 <br /> 2.067 12.02 2.067 10.73 <br /> 6946.0 <br /> 2,985 15.01 2.985 13.72 <br /> 6947.0 <br /> 3.304 18.31 3.304 17.02 <br />• 6948.0 <br />At the principal spillway elevation of 6945.2, the 1985 sediment storage capacity was 9.96 <br />ac-ft, whereas, the September 8, 1986 sediment survey indicates a sediment storage volume <br />of 8.67 ac-ft. The difference in sediment storage of -1.29 ac-ft can be attributed to <br />additional sediment being deposited during the year and possible surveying inconsistencies <br />from one year to the next. <br />Based on the updraina ge watershed characteristics, one 10-year, 24-hour precipitation <br />event would generate 4.28 ac-ft of sediment using M. U.S.L. E. <br />The equivalent of the sediment generated from approximately two 10-year, 24-hour <br />precipitation events could be stored beneath the principal spillway elevation based on the <br />1986 annual sediment survey. This is an adequate amount of sediment storage; therefore, <br />no remedial sediment clean out work is scheduled during the next year at this time. <br />Sedimentation Pond 007. Design information and calculations for this pond were submitted <br />• in a Technical Revision (August 14, 1986) to the Seneca II Permit Renewal Application and <br />subsequently approved by CMLRD. This pond, a new pond, ryas constructed in the fall of <br />7-11A-4 <br />