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represents about an acre of land within the permit boundary, the soil berms on the road are not <br />packed or covered, and the ditches, which are very steep at some locations, provide additional <br />disturbed area, and abundant sediment. Plus some of the source material for the road and ditch <br />(wash -plant reject material, also discussed November 11, 2015) may be much more erosive than <br />the reclaimed areas. The most observable impacts are seen within Pond 5 and outside the permit <br />boundary. The observable impacts of high volumes of runoff are primarily the result of <br />hydrological processes occurring within the permit boundary and the great amount of sediment <br />are partially from the eroded road and eroded road ditches. <br />Hydrological boundaries or watersheds do not follow permit boundaries. Erosion, infiltration, <br />runoff, and sediment yield that occur upstream and within the permit boundary have great impact <br />on hydrological processes downstream and outside the permit boundary. It is the case in this <br />instance where runoff generated upstream within the permit boundary contributes greatly to <br />erosion and sedimentation within and downstream beyond the permit boundary. Hydrological <br />processes within the permit boundary are contributing greatly to the observed erosion and <br />sediment yield within Pond 5 (within the permit boundary) and downstream near the green gate <br />(outside the permit boundary). <br />Erosion of soil from County Road 92 and its ditches has become a greater or more obvious <br />problem recently because of lack of maintenance. While EFCI was actively mining, any road <br />maintenance near the mine was accomplished either by the Fremont County maintenance crews <br />or by EFCI, so large gullies and ditches across the road did not form or were quickly repaired. <br />Road ditch armoring at erosive points were also used. For several years since EFCI stopped <br />mining and the majority of the reclamation was finished, Fremont County has been locked out of <br />the area and EFCI has only selectively maintained certain parts of County Road 92. <br />In addition, a low, relatively level, small area just south of the green gate on the west side of <br />County Road 92 has been operating as a sediment detention pond for some time, allowing some <br />erosion and sediment deposition to go mostly unnoticed. This area has received enough water <br />and sediment deposition that some of its juniper trees have died. The build-up of sediment depth <br />in this area has now caused recent high runoff flow to be redirected and concentrated across <br />areas to the east side County Road 92. <br />Runoff waters and sediment within a major portion of the permit boundary are contributing <br />greatly to the erosion and sediment deposition observed just north of the permit boundary (Bond <br />Release Map SL -03). A true sediment analyses of the reclaimed and non -mined lands within the <br />permit boundary may demonstrate or better identify areas or sub -watersheds that are contributing <br />greatly to erosion within and outside the permit boundary. Visual inspections in the field, <br />especially after rainfall events would also help. This is not accomplished with the simple <br />RUSLE model demonstrations presented as evidence that the reclaimed lands produce less <br />sediment than non -mined lands. One erroneous assumption was that greater vegetation cover on <br />lands would produce less annual sediment compared to less vegetation cover on the same lands. <br />This was demonstrated in both sediment reports with RUSLE, but it only demonstrated the site <br />with greater cover would have a lesser C -Factor, thus the RUSLE model output would also be <br />less, since this "demonstration" only changed the cover factor. This was all the original <br />sediment report provided and has again been inappropriately applied in the January 13, 2016 <br />