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FOURTH QUARTER 2002 <br />ENGINEERING INSPECTION <br />EAST YARD AND WEST VALLEY FILL <br />GOB DISPOSAL PILES <br />The approved Oxbow Mining, LLC (OMLLC) Mine permit document includes a requirement for <br />quarterly inspections of coal mine waste piles for stability. The inspection is to be performed by a <br />registered engineer or other qualified professional specialist, who is experienced in the construction <br />of earth and rockfill embankments. <br />On December 12, 2002, a visual inspection was performed of the East Yard and West Valley Fill <br />gob disposal areas, The East Yard gob- disposal area has reached its design capacity, ar~d no new <br />gob material has been placed since June of 2001. The East Yard pile is currently being covered <br />with a topsoil substitute cap, ranging from four to eight feet thick. During the quarter, the <br />approximate upper 75% of the slope was rough graded. Coverage of the upper road surface of the <br />pile has not yet been completed but is proceeding starting from the crest of the outslope to the <br />native slope. On November 18, 2002, the approved OMLLC seedmix was hand broadcast seeded <br />onto the outslope. Nothing was observed during the inspection that would indicate the pile has a <br />potential for failure. Safety berms are required on the downhill edge of the pile by the Mine Safety <br />and Health Administration. <br />The West Valley Fill has received gob material during the third quarter. Compaction tests are <br />required, as necessary, based upon the amount of material added to the waste area. Compaction <br />tests are 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 <br />present approximate 6175 elevation of waste material has been graded and covered with at least <br />four feet of suitable, non-toxic and non-combustible soil substitute materials. The second bench has <br />received rough grading with an approximate 2% grade. Nothing was observed during the inspection <br />that would indicate the pile has a potential for failure. <br />Q.UtiEA <br />spected by James A. er <br />__ 2 Z/zoo Z <br />Thomas C. An erson ate <br />Colorado Registered Professional Engineer No. 14726 <br />3737 N~N•y 133 ,, P.O. ~3ox X35 ~ 5or~,c'rset, Colorccic 8134 iJSA <br />TEL (970) 929-5i 2:~ Fr~X (970) 929-51 77 <br />