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5 | Page <br />sediment pond or containment area clean-out activities. <br />The interface between the reclaimed an un-reclaimed portions of the RDA was generally in good <br />repair although evidence of past drainage control problems is still evident. Straw wattles have <br />been placed along the eastern half of the interface but are not properly overlapped or keyed in. <br />However, the outer berm is now intact and drainage would flow away from the edge toward the <br />interior of the contour ditch. This diversion is close to requiring maintenance but is functional at <br />this time. An old small rill is present in the reclaimed bench on the eastern end of the interface. <br />This rill appears to be self-healing and does not cut down through the topsoil to refuse material. <br />Vegetation is establishing, and so bringing heavy equipment in to repair this feature would likely <br />be counterproductive. OSMRE and DRMS staff agreed that placing brush in the rill would be the <br />best way to encourage the feature to self-heal. <br />Sumps on both sides of the un-reclaimed RDA area are functioning to trap sediment before <br />drainage is routed down the side drains to Pond 008A. These sumps are easier to access and <br />clean than the pond. Both contained large amounts of coaly sediment, but the eastern sump is <br />smaller and should either be cleaned soon or enlarged to increase capacity. However, these <br />sumps are not designed sedimentation ponds and keeping them clean is simply in NECC’s <br />interest because it extends the time between Pond 008A cleanings (not a compliance issue). <br />The uppermost reclaimed contour ditch on the RDA had a slope of approximately 1%. <br />Vegetation is well-established on the reclaimed face, with trees establishing on the lowest bench. <br />A high proportion of bindweed (a List C weed) was noted on the reclaimed face, but vegetation <br />was otherwise good. Erosion was noted to the east of the RDA below the conveyor corridor. This <br />area is very steep and drains to Pond 008A. Although the surface was not disturbed by mining <br />activities, the area is contributing sediment to the pond and should be stabilized. <br />The reclaimed development coal waste pile (DCWP) was in good condition at the time of <br />inspection. Small patches of sparse vegetation and List C weeds (cheat grass and bindweed) were <br />noted, especially near the top of the reclaimed DCWP. No erosive features were found. The <br />DCWP is stable and water is routed off the pile as designed. <br />Erosion control practices on reclaimed coal mine waste banks are discussed in more detail in a <br />separate topic-specific oversight evaluation report. <br />The development waste disposal area #2 (DWDA#2) is constructed but un-reclaimed at this time. <br />Perimeter berms are in place and well-maintained. NECC has constructed a sump to catch <br />sediment prior to routing drainage into Pond 007. Sumps are generally easier to clean than <br />ponds, but access is limited here and sediment is accumulating at the outlet culvert. NECC has <br />placed material on the west end presumably to dry. Water is trapped within the end dump piles. <br />Although this is not a problem from a regulatory standpoint, this does not achieve NECC’s <br />desired effect of drying the material prior to permanent placement. <br />The stream-side embankment of DWDA #2 is well-bermed and marked on the outside as a <br />stream buffer zone. There is coaly material on the outslope in this area within the buffer zone. <br />This area was disturbed and coal material was left on the ground prior to the enactment of the