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APX O Page 2 <br />SEDIMENT POND CERTIFICATION <br />i•~ <br />1. Saturated material from the toe of the slope was excavated and mixed with the <br />dry material from the main embankment and placed and compacted. <br />Compaction tests were taken on December 2, 2004. The tests indicated a <br />relative compaction of over 92%. The compaction tests confirm that compacting <br />the embankment by wheel rolling with front end loaders is an acceptable method <br />to achieve required densities. Compaction test results are enclosed. <br />2. Competent material was placed and compacted in the toe of the embankment. <br />3. Anew primary spillway was installed. Pond Seal (bentonite) was placed at each <br />pipe joint to function as anti-seep collars. <br />4. A valve was placed at the inlet end of the primary spillway. <br />On December 3, 2004, I perfonned a final inspection of the reconstructed pond <br />embankment. I, J. E. Stover, have a wide variety of experience in the design and <br />construction of earth fill embankments. Nothing was observed during the inspection that <br />would indicate the pond has a potential for failure. There was no appearance of <br />erosion, instability, structural weakness or other hazardous conditions. There are no <br />required monitoring procedures or instrumentation other than monthly and yearly <br />inspections. There are no aspects which might affect stability and there is no required <br />maintenance. The sediment pond had water and ice within 3-feet of the primary <br />spillway at approximate elevation of 5454.. <br />The required capacity of the sediment pond is 0.54 A-F (ref. PAP Section 2.4.1). The <br />required water capacity of the sediment pond is 0.34 A-F {ref. Table 4.2-12). Therefore <br />the required sediment capacity for the pond is 0.20 A-F. The actual size of the pond <br />exceeds the required capacities listed in the permit. <br />The sediment pond has the following estimated capacity assuming no sediment build- <br />up: - <br />POND CAPACITY -ACRE FEET <br />Water Sediment Total <br />0.67 0.28 0.95 <br />To the best of my knowledge and belief, the impoundment(sediment pond at the <br />McClave Canyon Mine was repaired in accor~jji the approved plan and <br />applicable regulations. ~epp0 REG/Sly <br />Colorado <br />i~~ <br />McClave <br />Volume III <br />of/o6 <br />