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• <br />and just needed to be reestablished. <br />Bac~lling and Grading - Backfilling and grading was complete at the tipple area, the <br />conveyor corridor, and in the Moffat and West Ridge pit areas. The explosives storage area <br />and grizzly pads had been regraded and seeded. The facilities area pond had been <br />completely regraded and a rip rap lined channel through the area had been constructed. <br />One small area in the regraded tipple area did not drain very well as graded. The operator <br />should regrade the ditch on the south end of the tipple area, at the base of the conveyor <br />corcidor slope, so that water does not pool in this area. This could probably be achieved <br />by reducing the berm of the ditch on the uphill side'. Additionally, the ditch which carries <br />tipple area runoff to the tipple ponds should be redefined at the inlet and outlet of the <br />access road crossing culvert where regraded material is above the culvert flow line'. <br />The regraded conveyor corridor has fairly steep slopes (pre-mining slopes were also as <br />steep), on which the replaced topsoil might benefit from contour furrows until vegetation <br />is reestablished. <br />Observations for the Purpose of Assessing Reclamation for Phase I Bond Release <br />The Center Ridge regraded area, for which there was no pre-approved postmining <br />topography (mined pre-SMCRA), blends well with the surcounding topography. The <br />bac filled area appeared stable. rains a on the area appeared to be reestablts ed to pre- <br />mine conditions, but due to a lack of information on pre-crone conditions this could not be <br />positively determined. <br />There was one gully (approximately 50' long, 8-10" deep) on the north end of the Center <br />Ridge release azea. The gttlly looked like it had formed in the early post-reclamation period <br />and appeared to be stabtliztng. Vegetation was emerging in the sides and bottom of the <br />channel. <br />A small depression was observed on the extreme west end of the Center Ridge release area. <br />The depression was cone-shaped, roughly 4' deep at its deepest point, with an approximate <br />20' diameter. It appeared that the area was no longer settling, as there were no new scarps <br />apparent in or around the feature. Vegetation had reestabltshed on the scarp faces from <br />the initial movement. <br />The West Ridge area had been graded to the approved post-mining topography, with minor <br />exceptions. Reconstructed drainage patterns and slope gradients were as approved. The <br />steeppest slope on the reggraded area, which is in the drainage between Terraces 8 and 9 <br />(St/zNWt/a Sec. 24), is a 30% slope. <br />The west edge of the reclaimed West Ridge pit area is banked by a berm which is roughly <br />4' tall. This is a slight deviation from the approved post-mine topography, which called for <br />a small ridge to be placed roughly 75' in from the edge of the pit area boundary. The <br />existing configuration, however, ensures that drainage from the disturbed area will drain to <br />the West Ridge pond and not to the west onto undisturbed land. <br />The fourteen terraces and twenty-one check dams which were required to abate Notice of <br />Violation No. C-90-043 have been constructed as designed in the West Ridge Hydrologic <br />Reconstruction Plan. The structures are in excellent condition and functioning as intended. <br />A large precipitation event (in excess of a 100 year-24 hour event) earlier this summer <br />displaced the channel armor on a number of the check dams. The operator had <br />reconstructed all of the dams, and had improved them over the original design by placing <br />Edna Mine 2 Septembcr 7b, 1996 <br />