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. <br />T <br />The riprapped ditch between Ponds No.l and 2 is in good <br />condition in the upper two/thirds of its length. In this <br />area vegetation is growing between the riprap and there is <br />little evidence of ditch erosion. However, on the lower <br />one/third incision into the soil mantle is two to three feet <br />in magnitude. Replacement of the flagstone riprap into this <br />part of the ditch should deter further erosion. A small <br />alluvial fan has developed where the diteh enters Pond No.l, <br />but water retention volumes should not be impacted seriously <br />by this deposit. <br />Sedimentation Pond No.2 <br />A slight flow of water from the dewatering pipe outflows <br />onto riprap that is in good condition. The back side of the <br />dam is well vegetated and displays no rills or gullies of <br />significance. <br />The emergency spillway and associated outflow riprap down to <br />its junction with a natural drainage are in acceptable <br />condition, and show no indication of waterflow in the recent <br />past. The top of the dam is partially covered by vegetation. <br />The upstream dam face is heavily vegetated and the riser is <br />clear of debris with some water in the bottom of the <br />culvert. A small alluvial fan has developed where a <br />southeast oriented Lateral enters the pond area. Pond <br />storage volume should not be seriously affected by this <br />deposit, and the lateral appears to be in good condition <br />with no evidence of erosional damage. <br />Some minor erosional incisions occur along the riprapped <br />drainage that enters the pond area from the northeast. At <br />the foot of this drainage, where it enters the sedimentation <br />pond, a small alluvial deposit has developed. Thi's deposit <br />should not seriously impact the containment volume of Pond <br />#2. <br />Explosive Storaee Area Sedimentation Pond <br />Vegetation is growing inbetween flagstones in the riprapped <br />input ditch, which should help impede ditch erosion. In some <br />areas canopy cover approaches 50 percent on the ditch bottom <br />and flanks. There is no buildup of sediment at the point <br />where the ditch enters the pond, which indicates that the <br />Northwest Sediment Trap is functioning efficiently. <br />