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• procedure was used; the pond was analyzed for the largest anticipated disturbed drainage area that will <br />contribute runoff. It was estimated that this condixion would occur if atl of the proposed mining area is <br />disturbed and the area is in different phases of mining and reclamation. In addition, the structure was <br />conservatively designed to include adequate capacity for sediment storage and retention of the 10-year, <br />24-hour storm event. Finally, the design assumed the principal spillway is operable during the 25•year, <br />24-hour storm event and provides adequate freeboard to prevent overtopping of the embankments. The <br />SECAD output for the pond as-built conditions are attached. <br />CONSTRUCTION SUMMARY <br />SCC personnel; Dan Allen (Surveyor) and Roy Karo (Reclamation Manager) supervised the construction <br />of Pond 016A. Mr. Allen and Mr. Karo ensured that all work was performed in accordance with the <br />design and specifications. In addition, MWH personnel (consultants) were on site at several critical <br />occasions during construction to conduct compaction testing, soil analyses, etc. <br />Suitable materials excavated from the pond area and associated side-slopes were used in the <br />embankment construction. The material was placed and compacted in the embankment to meet or <br />exceed the design specifications. <br />I, Robert J. Shevling (SCC Engineering Managed inspected the embankment construction on a frequent <br />t•asis during construction and upon completion of the as built to ensure proper construction of <br />Sedimentation Pond 016A and to satisfy the requirements of Rules 4.05.6 and 4.05.9. To xhe best of <br />• my knowledge, based upon my professional expenise, and to the extent possible, Pond 016A was <br />constructed in accordance with prudent state-of-the-an methods for earthen embankment construction. <br />Further, the structure was constructed in compliance with the approved design, to the extent possible, <br />as specified in Attachment 13-56 of SCC's approved mine permit. Minor field adjustments in horizontal <br />and vertical alignments were necessary during construction to compensate for unanticipated natural <br />conditions, limit the disturbed area, and construct a structure consistent wish the reclaimed topography. <br />-fo the best of my knowledge and belief, the field adjustments made during construction are in <br />conformance with the intent of the approved design plans and specifications. <br />• <br />73-51-2 <br />