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i • <br />GEOTECH? <br />b Civil, Structural & Geotechnical Engineers <br />222 South Park Ave. o Montrose, CO 81401 <br />Ph„ (970) 249-6828 o FAX: (970) 249-0945 <br />March 11, 2009 <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 March 3, 2009. <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 previously recorded in the B-axis of <br />inclinometer BG05-05 has not progressed since the December 2008 readings. The previous <br />movement is interpreted to be due to settlement of the coal refuse. <br />Vibrating Wire Piezometers <br />Five vibrating wire piezometers, designated VWP-01 through VWP-05, were installed in gob at <br />Gob Pile No. 2 in June 2005. The piezometers were grouted in drilled boreholes as described <br />by Buckhorn Geotech (2006). Piezometer locations are presented on the attached site plan. <br />Bowie Gob Pile 2 Instrumentation Monitoring March 2009.doc <br />Project ##05-126-GEO <br />Page 1 of 2