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2.05.3 <br />Pond Bottom Elevation versus Ground Water Elevation <br />Pond <br />Pond Bottom <br />Groundwater <br />Difference <br />1 <br />4463 <br />4454 <br />8 <br />2 <br />4460 <br />4457 <br />3 <br />3 <br />4465 <br />4452 <br />13 <br />(ii)(C) Operations and maintenance requirements for ponds 1 -3 are the same. <br />Dewatering should occur within 48 hours after the storm event which cause <br />significant water accumulation. Water will be maintained at or below the <br />maximum sediment level. Water will be pumped to an on -site storage tank, that <br />when full, will be taken to an approved disposal facility. The closest commercial <br />disposal area for water removed from the sediment ponds is in Cisco, Utah. <br />Sediment will be removed from the ponds when the sediment level reaches no <br />more than 75% of the designed sediment capacity. Sediment removed from the <br />sediment ponds will be disposed of at an approved disposal facility. <br />As discussed previously, sediment ponds 1 -3 will be lined with twelve inches of <br />recompacted material, and have twelve inches of soil placed over the liner in <br />order to prevent damage during sediment cleanout. Permanent sediment poles <br />will be placed at the top of the soil cover layer and will be cast in concrete. A <br />sediment pole will be placed in the center, and at each corner of ponds 1 -3, and <br />will have a zero elevation at the top of the soil cover layer. During pond cleanout, <br />the trackhoe operator will work with a surveyor to assure sediment is not removed <br />beyond the zero elevation in the center of the pond, and that the sediment is <br />cleaned out at a 2:1 on the pond side slopes. Adhering to the zero sediment <br />level will protect the twelve inches of soil cover, as well as the twelve inches of <br />soil liner. <br />(ii)(D) Sediment ponds will be removed during final reclamation and backfilled with <br />material from the construction materials stockpile. Fill material will be spread in <br />layers approximately 12 inches deep, and such lifts made uniformly over long <br />stretches and for the full width of the pond. Each lift will be moistened or dried to <br />a uniform moisture content suitable for maximum compaction. The fill material <br />shall be compacted until it attains at least 90% of the maximum dry density <br />attained in a laboratory compaction test in accordance with ASTM D698. <br />Compaction testing will be taken at a frequency and location of not less than one <br />Permit Application 2.05 -20 01/12 <br />