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Construction Report -Section 28 Pond <br />installation. Some moisture addition was needed to bring this material to acceptable <br />limits for compaction. A permit change was made (TR-68) to develop an additional <br />borrow source within a colluvial fan deposit approximately 1,700 feet to the southwest of <br />the impoundment. While the fan deposit contained a substantial quantity of large rocks <br />requiring segregation, the deposit proved to be an exceptional source of plastic fines. <br />No moisture addition was needed for any of the fill obtained from the borrow site. <br />Compaction testing was also conducted as directed by the field engineer. NWCC <br />Laboratories provided this service. Attachment A-3 provides the compaction test <br />results. Testing was done more frequently on the keyway and the lower lifts to establish <br />a method of uniformly achieving compaction. Actual compaction exceeded 95 percent <br />of maximum dry density. When a compaction test failed, a successful retest was <br />achieved before an additional material was added. Thirty different compaction tests <br />were done over seven different days. <br />A final field survey was conducted on November 1, 2007 by Chad Fox of Epp & <br />Associates Surveying. This data was used to produce the final as-built drawing and to <br />calculate the actual storage volume. <br />A Parshall Flume with a 9 inch throat width was installed below the downstream toe on <br />November 2, 2007. A design change was made to use this size flume instead of the 24 <br />inch throat width originally specified. The half-pipe culvert below the outlet was also <br />installed at this time. <br />The embankment will be broadcast seeded with the approved seed mixture at the <br />specified seeding rate. <br />Page 4 <br />