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; GEOTECH 1? Civil, Structural <br />& Geotechnical Engineers <br />222 South Park Ave. ° Montrose, CO 81401 <br />Ph.: (970) 249-6828 , FAX: (970) 249-0945 <br />December 5, 2008 <br />Bowie Resources, LLC <br />Attn: Bill Bear <br />P.O. Box 483 <br />Paonia, CO 81428 <br />RE: SUMMARY OF INSTRUMENTATION MONITORING <br />BOWIE GOB PILE NO. 2 <br />Dear Bill, <br />Buckhorn Geotech, Inc. has conducted on-going monitoring of inclinometers and vibrating wire <br />piezometers previously installed at Gob Pile No. 2 for Bowie Resources, LLC (Bowie). In 2005, <br />three inclinometers were installed to monitor movement of placed gob and 5 vibrating wire <br />piezometers were installed to monitor pore pressures developed within the gob. Installation <br />details of the instrumentation are presented by Buckhorn Geotech (2006). This letter <br />summarizes instrumentation monitoring through December 3, 2008. <br />Inclinometers <br />Three inclinometers, designated BG05-4, -5, and -7, were installed at Bowie's Gob Pile No. 2 in <br />August 2005. The inclinometers were installed through the coal mine waste and approximately <br />20 feet into the native foundation soils. Locations of the inclinometers are presented on the <br />attached site plan. Baseline readings were taken on 8/10/05 and subsequent readings have <br />generally been taken quarterly. Cumulative displacement curves with respect to the baseline <br />readings are presented as an attachment to this letter for each inclinometer. Axis "A" reflects <br />deformation with depth in the direction of anticipated movement, while Axis "B" is orthogonal to <br />Axis A. <br />No definite indications of deep-seated instability of the gob are observed in the inclinometer <br />monitoring data. As described in previous letters, displacements indicated on the plots for the <br />upper ten feet of the inclinometers are attributed to placement of cover soil on the face of the <br />waste bank in late 2006/early 2007. Movement is indicated in the B-axis at inclinometer BG05- <br />05. Movements in the B-axis vary from zero at a depth of approximately 35 feet to <br />approximately 0.75 inch near the surface. This movement is interpreted to be due to <br />consolidation settlement of the coal refuse. The linear plot of the displacement does not <br />indicate a discrete shear zone. Also, the majority of the indicated movement is in the B-axis <br />(parallel to the slope of the refuse bank, rather than down the slope of the refuse bank). <br />Additional monitoring is recommended to further characterize the movement in BG05-5. <br />Bowie Gob Pile 2 Instrumentation Monitoring Dec 2008.doc <br />Project #05-126-GEO <br />Page I of 2