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Y <br />6) Dam Slopes Design: 2.SH:1.OV. Measured: Outslope 2.SH:1.OV <br />with large rock (>24" diameter) placed near gulch. Inslope: <br />2.SH:1.OV. Initially, the inslope measured approximately <br />1.5H:1.OV, but additional work was done in lessening the slope to <br />2.5H:1.OV. Additional fill was also added to the outslope of the <br />embankment. The additional fill was obtained from the western <br />side of the pond and was moved in place with a large bulldozer <br />and hydraulic excavator. Prior to fill moving and placement, both <br />sides of the embankment were cut in a "vee" shape to provide a <br />keyway to anchor the previous fill to the new fill. Compaction <br />was accomplished by controlling the moisture level of the fill to <br />near optimum and by compaction with the hydraulic excavator and <br />dozer. Part of the inslope side of the embankment (approximately <br />5 feet vertically) is incised in original ground. <br />7) Pond Death Design: 15.0 ft. Measured: 15.9 ft. <br />8) Rip Rap Lining in Emergency Spillway Design: 12" thickness of <br />10" to 12" rip rap, durable rock. Measured: 12" thickness of 10" <br />to 12" rip rap, durable rock. <br />9) Sediment Storage Volume: Design: 0.22 acre-feet. Measured: 0.4 <br />acre-feet. <br />10) Storm Detention Volume: Design: 4.08 acre-feet. Measured: 4.1 <br />acre-feet ± 4~. <br />11) Rip rap at Discharge of Principal Spillway: Design 8" <br />diameter durable rock. Measured: as designed. <br />12) Compaction of Embankment: Since my first inspection occurred <br />before the final dam was constructed, I was able to determine the <br />effectiveness of the compaction within the dam itself. The weight <br />of the large hydraulic excavator on the dam during construction <br />was able to achieve proper compaction, in the order of 85A; to 90~ <br />of the maximum dry density. This was also verified in the final <br />inspection. During the additional work to lessen the embankment <br />slopes to 2.5H:1.OV, the keyway and all fills were compacted to <br />85~ to 90~ of the maximum dry density. <br />There was no evidence of cracking, bulging, sliding, seepage or <br />other construction problems. 1 certify that the sediment pond at <br />the Rimrock Mine has been constructed according to the plans <br />