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SUCKHORt <br />June 21, 2013 <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, 2nd QUARTER 2013 <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) since 2005. This letter summarizes instrumentation monitoring at <br />CWDA No. 2 through June 19, 2013. <br />Inclinometers <br />Three inclinometers, designated BG05 -04, -05, and -07, 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 June 19, 2013 readings were taken at inclinometers BG05 -05, <br />and 07 and are reported herein. A second visit was necessary on June 22, 2013 to take a <br />reading for inclinometer BG05 -04 which had been inadvertently buried by gob and had to be re- <br />exposed. The readings for BG05 -04 are also included in this report. <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 />readings. The previous movement in the B -axis of BH05 -05 is interpreted to be due to <br />settlement of the coal refuse. <br />2nd Qtr Monitoring Report.doc PN #05-126 -GEO <br />Page 1 of 4 <br />