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%' <br />1~ <br />' _ - <br />SECOND QUARTER 2004 <br />ENGINEERING INSPECTION <br />EAST YARD AND WEST VALLEY FILL <br />COAL MINE WASTE DISPOSAL PILES <br />The approved Oxbow Mining, LLC (OMLLC) Mine permit includes a requirement for quarterly inspections <br />of coal mine waste piles for stability. The inspection is to be performed by a registered engineer or other <br />qualified professional specialist, who is experienced in the construction of earth and rockfill embankments. <br />On Tune 8 and 9, 2004, visual inspections were 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. Additional supplemental hydromulch and seed was applied on <br />October 21, 2003. The seeded slope was inspected for signs of erosion or instability and initial vegetation <br />establishment. No erosional featwes were noted requiring repairs to seeded areas. Nothing was observed <br />during the inspection that would indicate the pile has a potential for structural failwe. Safety berms <br />continue to be required by the Mine Safety and Health Administration on the downhill edge of the access <br />ramp. <br />The West Valley Fill has received some additional waste material during the second quarter of 2004. <br />Compaction tests are required, as necessary, based upon the amount of material added to the waste area. <br />Compaction tests are planned as material is added to the waste area. <br />The outslope located between the second bench (approximate 6150 elevation) and the present approximate <br />6200 elevation of waste material and seeded with the approved seedmix on October 21, 2003 was inspected <br />for signs of erosion and initial establishment of seeded species. No erosional featwes were noted requiring <br />repairs to any seeded areas. <br />The third bench (approximate 6200 elevation) setback has been initiated in preparation for the final lift of <br />waste material. The ramp constructed on the west limit of the waste pile to provide access to the II West <br />Coal Refuse Facility light use road and haul road construction continues to be utilized and developed. <br />No springs or seeps were noted. Swface drainage control features are performing according to the plan. <br />Nothing was observed during the inspection that would indicate the West Valley Fill has a potential for <br />structural failwe. <br />~it^f'~ it / e~ <br />spected by James A. iger <br />/~ /'~ ~-. <br />C. Anderson <br />Date <br />Colorado Registered Professional Engineer No. 14726 <br />31°~7 Nv-y'•33 P.O. Box 535 Sornerset, Colorado 8143 l1SA <br />TEL ~4?0) 424-5122 ~ FAX 0470} 424-5i 7i <br />