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l <br />Civil, Structural & Geotechnical Engineers <br />222 South Park Ave. • Montrose, CO 81401 <br />Ph.: (970) 249 -6828 • FAX: (970) 249 -0945 <br />September 25, 2013 <br />Bowie Resources, LLC <br />Attn: Bill Bear <br />P.O. Box 483 <br />Paonia, CO 81428 <br />RE: BOWIE COAL WASTE DISPOSAL AREA NO. 2 <br />SUBJECT: SUMMARY OF INSTRUMENTATION MONITORING, 3rd QUARTER <br />2013 <br />Dear Bill, <br />Buckhorn Geotech, Inc. (BGI) has conducted on -going monitoring of inclinometers and <br />vibrating wire piezometers previously installed at Coal Waste Disposal Area No. 2 (CWDA <br />No. 2) for Bowie Resources, LLC (Bowie) since 2005. This letter summarizes <br />instrumentation monitoring at CWDA No. 2 through September 25, 2013. <br />Inclinometers <br />Three inclinometers, designated BG05 -04, -05, and -07, were installed at CWDA No. 2 in <br />August 2005. The inclinometers were installed through the coal refuse and <br />approximately 20 feet into the native foundation soils. Locations of the inclinometers are <br />presented on the attached site plan. Baseline readings were taken on 8/10/05 and <br />subsequent readings have generally been taken quarterly. Cumulative displacement <br />curves with respect to the baseline readings are presented as an attachment to this letter <br />for each inclinometer. Axis "A" reflects deformation with depth in the direction of <br />anticipated movement, while Axis "B" is orthogonal to Axis A. During our site visit on <br />September 2, 2013 readings were taken at inclinometers BG05- 04, 05, and 07 and are <br />reported herein. <br />Based on our latest readings, no definite indications of deep- seated instability of the gob <br />are observed in the inclinometer monitoring data. As described in previous letters, <br />displacements indicated on the plots for the upper ten feet of the inclinometers are <br />attributed to placement of cover soil on the face of the waste bank during normal <br />operations. Movement previously recorded in the B -axis of inclinometer BG05 -05 has not <br />progressed since the December 2008 readings. The previous movement in the B -axis of <br />BH05 -05 is interpreted to be due to settlement of the coal refuse. <br />3rd Qtr Monitoring Report.doc PN #05- 126 -GEO <br />Page 1 of 5 <br />