2015-03-04_GENERAL DOCUMENTS - C1981020

Home Browse Search

above the abandoned underground mine workings. The field inspection of the reclaimed light use road, mine portal area, haul road, and coal mine waste disposal area at Munger Canyon Mine demonstrated that backfilling and grading were performed in a manner to achieve stable AOC, that erosion and sediment control measures were being implemented successfully, and that vegetation had been established, to varying degrees. DRMS’ latest inspection of the Munger Canyon Mine, dated October 30, 2014, resulted in zero enforcement actions, with none pending. The first area evaluated was a 0.6 acre former topsoil pile adjacent to the reclaimed coal mine waste disposal area. The observed surface reclamation featured extensive hummocking prior to seeding to help establish vegetation, assist the soil in holding water, and control erosion and sediment transport in runoff. Vegetation consisted of grasses and forbs and was well established, elk scat was also observed. Next, the Team inspected the 2.0 acre site of the reclaimed coal mine waste disposal area, approximately 400’ x 115’ in size. Here again, the surface was highly roughened prior to seeding, and appeared well vegetated. There was no evidence of erosion or instability, and the pile featured a permanent, shallow, riprapped perimeter ditch as part of the approved design. It was determined that a small sliver of land here, approximately 70’ x 30’, would not be eligible for Phase II bond release, as the area was redisturbed in October with the removal of a road culvert. The Team then hiked the 6.5 acre reclaimed haul road up to the reclaimed mine portal area. The hike took the Team across a total of ten reclaimed culverts which had been constructed as permanent rip rapped fords, identified as “A,” “A1,” “A2,” “B,” “C,” “D,” “E,” “F,” “G,” and “H” in the approved permit. The reclaimed haul road itself was nearly indistinguishable from the surrounding terrain. One Team member who had visited the Munger Canyon Mine extensively in the 1990s remarked at how nearly unrecognizable the site was, compared to its active mining heyday. Extensive elk scat was observed here as well, indicating the Munger Canyon Mine site is succeeding in its wildlife and grazing post-mining land use. Vegetation at the 3.6 acre mine portal area consisted of forbs, grasses, and sagebrush. The reclaimed surface was well-roughened, again, aiding in moisture retention and therefore vegetative establishment, controlling erosive sheetflow, and hampering sediment transport. At this point Jim Stover removed a silt fence at the end of the mine portal area, under the sandstone outcrop, which was no longer necessary to prevent topsoil loss. The final stop on the Team’s trek through Munger Canyon was the 1.6 acre reclaimed light use road. The road wound through the bottom of the canyon, more or less along Munger Creek. Compared to the rest of the acreage proposed for bond release, this portion was the least successful in terms of vegetative establishment. However, this was due to a major rain event in September that caused Munger Creek to jump its channel and flow across much of the canyon floor, and not a failure of reclamation operations or to the extent that Phase II bond release could not be granted. Depth-of-topsoil test holes were dug at each stop along the Team’s tour. All depth-of-topsoil holes reported at least six inches of topsoil coverage, as per the approved reclamation plan. Notification of the proposed bond release was published weekly in the local Daily Sun newspaper from October 24 through November 14, 2014. All participants expressed confidence that this bond release would be approved. Please address any questions concerning this report to Spencer Shumate, Natural Resources Specialist, jshumate@osmre.gov or (303) 293-5046.