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The pond footprint was to be left in place, with a maintenance free outlet created so that <br /> the ponds could dewater without over-topping the embankment. The embankments were <br /> to be seeded with an uplands seed mixture, while the perimeter of the pond at or near the <br /> water level elevation was planted with seed and transplants appropriate to a wetlands <br /> environment. <br /> In order to create these maintenance free wetlands areas from the existing sediment <br /> ponds, the CMP dewatering devices had to be removed, and a durable, maintenance free <br /> dewatering device was to be installed. The cut slopes created as a result of CMP <br /> removal, and any other adjacent or incidental disturbances were to be revegetated. <br /> The construction sequence followed was identical at each pond, and generally proceeded <br /> as described below: <br /> The pond was dewatered if necessary to below the invert elevation of the <br /> corrugated metal pipe dewatering device. Any water pumped from a pond was <br /> passed through silt fence prior to discharging to a receiving stream. <br /> The corrugated metal pipe dewatering device was excavated from the <br /> embankment. <br /> Once exposed, the dewatering devices were lifted from the excavation and placed <br /> on a trailer for removal from the site. <br /> - Typically, an excavated cut approximately five to six feet deep by five to six feet <br /> wide at the base by twenty feet long was created within the embankment at each <br /> pond as a result of excavating the dewatering device. The side slopes of the <br /> excavation were graded to a 2H:1 V or shallower configuration. The slope of the <br /> base of the excavation mirrored the gradient of the base of the corrugated metal <br /> pipe dewatering device, prior to its removal,thus the water surface elevation of <br /> the pond did not change. <br /> - The cut created during excavation of the corrugated metal pipe dewatering device <br /> was used as the principle spillway after reclamation was finished. The cut was <br /> lined with native rock riprap along the base and partially up the sides. The cut <br /> area above the riprap was severely scarified and then seeded. Scarification acts to <br /> disrupt surface flows and to promote revegetation potential. <br /> - Silt fencing was placed below each excavation following completion of work to <br /> inhibit sediment transport from the site until vegetation became established. <br /> The side slopes of the CMP excavation, as well as the top of the embankment were <br /> seeded using an appropriate, upland seed mixture. Wetland species appropriate to site <br /> conditions were planted around the margins of each pond. In addition, willows collected <br /> from nearby areas were transplanted along the perimeter of any ponds where water <br /> availability seemed capable of supporting such species. <br /> Evaluation of the portions of the ponds covered by the permit during the 2005 field <br /> season indicates that each excavated area is stable and non-erosive. The base and lower <br /> portions of the excavated cut slopes are stable as a result of the riprap placed in these <br /> locations. No undercutting or by-pass of the riprap was observed. Vegetation has <br /> 3 <br />