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December 19, 2012 <br />Bowie Resources, LLC <br />Attn: Bill Bear <br />P.O. Box 483 <br />Paonia, CO 81428 <br />Civil, Structural & Geotechnical Engineers <br />222 South Park Ave. • Montrose, CO 81401 <br />Ph.: (970) 249 -6828 • FAX: (970) 249 -0945 <br />RE: BOWIE COAL WASTE DISPOSAL AREA NO. 2 <br />SUBJECT: SUMMARY OF INSTRUMENTATION MONITORING, 4thd QUARTER 2012 <br />Dear Bill, <br />Buckhorn Geotech, Inc. (BGI) has conducted on -going monitoring of inclinometers and vibrating <br />wire piezometers previously installed at Coal Waste Disposal Area No. 2 (CWDA No. 2) for <br />Bowie Resources, LLC (Bowie). In 2005, three inclinometers were installed to monitor <br />movement of placed refuse and five vibrating wire piezometers (VWP's) were installed to <br />monitor pore pressures developed within the coal refuse. Installation details of the <br />instrumentation are presented by BGI (2006). Three additional vibrating wire piezometers were <br />installed in June 2009. Due to damage to existing vibrating wire piezometers, an additional two <br />VWP's (VWP -9 and VWP -10) were installed on May 18, 2012. This letter summarizes <br />instrumentation monitoring at CWDA No. 2 through December 19, 2012. <br />Inclinometers <br />Three inclinometers, designated BG05 -4, -5, and -7, were installed at CWDA No. 2 in August <br />2005. The inclinometers were installed through the coal refuse and approximately 20 feet into <br />the native foundation soils. Locations of the inclinometers are presented in Table 1 and 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. During our site visit on December 18, 2012 readings were taken at inclinometers BG05- <br />04, 05, and 07 and are reported herein. <br />Based on our latest readings, no definite indications of deep- seated instability of the gob are <br />observed in the inclinometer monitoring data. As described in previous letters, displacements <br />indicated on the plots for the upper ten feet of the inclinometers are attributed to placement of <br />cover soil on the face of the waste bank during normal operations. Movement previously <br />recorded in the B -axis of inclinometer BG05 -05 has not progressed since the December 2008 <br />4th Qtr Monitoring Report.doc <br />Project #05- 126 -GEO <br />Page 1 of 3 <br />