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?C I I M <br />SECOND QUARTER 2009 <br />ENGINEERING INSPECTION <br />EAST YARD, WEST VALLEY FILL AND II WEST <br />COAL MINE WASTE DISPOSAL PILES <br />The approved Oxbow Mining, LLC (OMLLC) Mine permit includes a requirement for quarterly inspections of <br />coal mine waste piles for stability. The inspection is to be performed by a registered engineer or other qualified <br />professional specialist, who is experienced in the construction of earth and rockfill embankments. On June 22, <br />2009 visual inspections were performed of the East Yard, West Valley Fill and 11 West coal mine waste disposal <br />areas. Three successful compaction tests were performed during the quarter on April 27, 2009. Copies of the test <br />are attached herein for the Division's information. <br />EAST YARD - The East Yard disposal area has reached its design capacity, and no new waste material has been <br />placed since June of 2001. The revegetated slope was inspected for signs of erosion or instability and vegetation <br />establishment. No erosional features were noted requiring repairs to revegetated areas. The covering of the <br />waste pile is considered complete. Nothing was observed during the inspection that would indicate the pile has a <br />potential for structural failure. <br />WEST VALLEY FILL - During the second quarter, no waste was hauled to the West Valley Fill area. The <br />elevation of the waste pile was surveyed at the approximate 6231' elevation. This existing waste will be <br />rehandled to II West at a later time. <br />The revegetated outslope located between the fill slope toe to the approximate 6200' elevation was inspected for <br />signs of erosion and instability. No erosional features were noted requiring repairs to any vegetated areas. The <br />third bench (approximate 6200' elevation) setback remains established for the final lift of waste material and the <br />ramp constructed on the waste pile to provide access to the II West Coal Refuse Facility light use road and haul <br />road. These two roads continue to be utilized. No springs or seeps were noted. Surface drainage control features <br />are performing according to the plan. Nothing was observed during the inspection that would indicate the West <br />Valley Fill has a potential for structural failure. <br />11 WEST - The Il West disposal area received approximately 2720 CY of additional coal mine waste material <br />during the second quarter of 2009. The elevation of waste material is at the approximate 6093' elevation. The <br />material has been worked to meet compaction requirements. No springs or seeps were noted. Surface drainage <br />control features are performing according to the plan. The recent fall seeded areas remain stable and initial <br />vegetative establishment considered good. Nothing was observed during the inspection that would indicate the 11 <br />West Fill has a potential for structural failure. <br />V1 <br />Inspected by James Kiger <br />?t??.. r-,j ?:), ? ?-7 7Z9IZ-Zo09 <br />Thomas C. Anderson Date <br />Colorado Licensed Professional Engineer No. 14726 <br />3737 Hwy 133 • P.O. Box 535 • Somerset, Colorado 81434 USA <br />TEl_ (970) 929-5122 • FAX (970) 929-5177