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~"" INSPECTION REPORT Site: National [{ing Caal Mine, Hesperus, Colorado Inspected By: Don R. May, P.E., Project Engineer Inspection Date: quarterly Inspection, September 24, 1994 Porsds_ Tt,e east and west sedimentation ponds are in good c•orsdition. There are no signs of erosion or excessive filling in of the ponds or tl'se approach channel:. The condition of the spillway arsd low flow outlet have not changed since the last inspection. Sorne water in the We ,t. Pond whir_.h is r,pt being drained by the low flow outlet. See previrnas reports for recommendations. Llrain-,E!e Pitrrses_ The erosion problems around the outlet of the two 19 inch blar_.k plastic corrugated pipes lor_ated behind the office rFF,crted during the last. inspection have been fixed. The hay bale sedirner,t. trap on the Eastside channel has formed a drop in the channel invFrt: of about 3 feet and could possibly induce erosion. The bale :;h+,uld be removed and replar.ed. Apparently tl~,e area received a large rr+infn7l rFr•er~tly. There are signs of accelerated erosion in the channel which has exposed bedrock. There is no definable channel between the toe of the waste pile and th«: Eastside Channel. The drainage plan calls for a small channel a+, t,},P tr,r'., All other ditr•hes ar,d pipes appeared in good corsclitior,. Fxr_.Fpt for the items cited above al 1, drainage features have been conr;t.r+-,ctPd and are operating as stated in the drainage plan submitted to the Division of Minerals and Geology. Coal Waste Pile: The plar..ement of r,ew material appears to be in smt,ll 1if t~ along the lower front_edge of the pile riccorrl.i.ng t.o i;hc plan. _ Compaction has been achieved by repeated passes of the heavy equipment., used in rnovir,g the waste material. It appears as thrJ,,igY, water from thn top of th,e pile has flowed down the face durirsg tkse lager rainstorm. This has generated rills on the fade of the pile one which appears to l', Five been fixed. Some ponding exists ors the top of the pile. A mare defined drainage channel along the top of the pile is needed. TF,ere are r,o signs of structural instability on the waste pile. The fill nn the waste pile has been r_onstTSlcted as speciflerl in the design approved by the Division of Minerals and Geology. NOTE: Due to a camera malfunction there are no photographs with this; report.