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., <br />/~~. <br />. ~~~ ~ . <br />l ;Jlsl._~,~~.~ _ '~ ,.; <br />FOURTH QUARTER 2003 <br />ENGINEERING INSPECTION <br />EAST YARD AND WEST VALLEY FII.L <br />COAL MINE WASTE DISPOSAL PILES <br />The approved Oxbow Mining, LLC (OMLLC) Mine permit document includes a requirement for quarterly <br />inspections of coal mine waste piles for stability. The inspection is to be performed by a registered engineer <br />or other qualified professional specialist, who is experienced in the construction of earth and rockfill <br />embankments. <br />On December 19, 2003, a visual inspection was performed of the East Yard and West Valley Fill coal mine <br />waste disposal areas. The East Yard disposal area has reached its design capacity, and no new waste <br />material has been placed since June of 2001. The East Yard pile outslope was seeded with the approved <br />OMLLC seed mix in the Fall of 2002. The seeded slope was inspected for signs of erosion or instability. <br />No erosional features were noted requiring repairs to seeded areas. Initial first year vegetation establishment <br />is proceeding. Additional supplemental hydromulch and seed was applied on October 21, 2003. Nothing <br />was observed during the inspection that would indicate the pile has a potential for structural failure. Safety <br />berms continue to be required by the Mine Safety and Health Administration on the downhill edge of the <br />access ramp. <br />The West Valley Fill has received waste material during the fourth quarter of 2003. Compaction tests are <br />required, as necessary, based upon the amount of material added to the waste area. Compaction tests are <br />planned as material is added to the waste area. <br />The portion of the outslope located between the second bench (approximate 6150 elevation) and the present <br />approximate 6200 elevation of waste material has been graded and covered with at least four feet of <br />suitable, non-toxic and non-combustible soil substitute materials. The second bench has received final <br />gading with an approximate 2% grade. The outslope had received final grading and surface scarification in <br />preparation for hydro-mulching and seeding. Hydromulch, 186-0 fertilizer and the approved seedmix was <br />applied on Oc[ober 21, 2003. The third bench (approximate 6200 elevation) setback has been initiated in <br />preparation for the final lift of waste material. A ramp has been constructed on the west limit of the waste <br />pile to provide access to the II West Coal Refuse Facility light use road and haul road construction. <br />No springs or seeps were noted. Surface drainage control features are performing according to the plan. <br />Nothing was observed during the inspection that would indicate the pile has a potential for failure. <br />4n-u1 ~ ~ 7~ f ` - <br />nsprcted by James A. Ciger <br />~ ~7 ~ <br />Thomas C. Anderson 'Date <br />Colorado Registered Professional Engineer No. 14726 <br />3737 Hwy 133 • P.G. Box 535 Somerset, Colorado 81434 USA <br />iEL (970) 929-5122 • F.AX (970) 929-5177 <br />