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'~ <br />6) Dam Slopes Design: 2.SH:1.OV. Measured: Outslope 2.SH:1.OV with large rock <br />(>24" diameter) placed near gulch. Inslope: 2.SH:l.OV. The slopes were well-vegetated <br />in all locations and showed no evidence of erosion or gullying of any kind. <br />7) Pond Deoth Design: 15.0 ft. Measured: 15.9 ft. Water level was approximately 1.5 <br />feet at the time of the inspection. <br />8) Rin Ra,p Lining_in Emergency Spillwav Design: 12" thickness of 10" to 12" rip rap, <br />durable rock. Measured: 12" thickness of ]0" to 12" rip rap, durable rock. <br />9) Sediment Storage Volume: Design: 0.22 acre-feet. Measured: 0.4 acre-feet. <br />10) Storm Detention Volume: Design: 4.08 acre-feet. Measured: 4.1 acre-feet t 4%. <br />11) Rip rap at Discharge of Principal Spillway: Design 8" diameter durable rock. <br />Measured: as designed. <br />12) Slope Stability: There was no evidence of seepage anywhere along the outside of <br />the embankment or the principal spillway pipe although the pond did contain water. <br />There was also no evidence of cracking, bulging, slipping or other signs of slope <br />instability. Vegetation was excellent on the top of dam and all sidelsopes. Previous <br />compaction tests done on the dam material were within specifications. <br />As a professional engineer experienced in embankment slope stability design, <br />construction and maintenance, I am confident that the dam meets the long term slope <br />safety factor of 1.3. In fact, past experience indicates that the slope safety factor is <br />most likely above 2.0. It is stable for the following reasons: <br />- the reconstructed slopes are 2.SH:1.OV, which is mild for a small pond with a height <br />less than ]0 feet. <br />- there are no weak spots in the original ground or springs or seeps which could <br />interfere with stability. <br />- the principal spillway has been properly compacted so that piping will not occur. <br />- the dam has been constructed in lifts with proper compaction as the independent data <br />shows. <br />13) Dam Height <br />The dam height as measured from the bottom of the original ground to the bottom of <br />the emergency spillway is 9.9 feet. for this reason, the dam does not meet the large <br /> <br />