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970 - 249 -6828 ■ 800 - 865 -9847 (fax) ■ 222 South Park ■ Montrose, Colorado 81401 ■ www.dowl.com <br />BOWL <br />April 17, 2015 <br />Huddleston -Berry Engineering and Testing, LLC <br />640 White Avenue <br />Grand Junction, CO 81501 <br />Attention: Mike Berry, PE <br />SUBJECT: First Quarter 2015 Summary of Inclinometer and Active Vibrating Wire <br />Piezometer Data through March 11, 2015, Bowie Mine No. 2, Coal <br />Waste Disposal Area No. 2 <br />Dear Mr. Berry, <br />DOWL has conducted quarterly monitoring of inclinometers and vibrating wire piezometers at <br />Coal Waste Disposal Area No. 2 (CWDA No. 2) for Bowie Resources, LLC (Bowie). This report is <br />intended to cover the time period of January through March 2015. Per DRMS and your <br />instructions, vibrating wire piezometer readings for all active piezometers are taken quarterly <br />along with inclinometers. <br />Vibratina Wire Line Piezometers <br />Table 1. Summary of VWP Pore Pressures <br />VWP ID # <br />Initial Pore <br />Pressure <br />(psi) <br />1/6/15 Pore <br />Pressure <br />(psi) <br />3/11/15 Pore <br />Pressure <br />(psi) <br />Difference <br />Since <br />Installation <br />(Psi) <br />Difference <br />Since Last <br />Reading <br />(Psi) <br />VWP -05 <br />6.8 <br />2.3 <br />1.8 <br />-5.0 <br />-0.5 <br />VWP -06 <br />11.3 <br />16.8 <br />17.0 <br />+5.7 <br />+0.2 <br />VWP -08 <br />1 8.2 <br />1 9.8 <br />1 9.6 <br />+1.4 <br />1 -0.2 <br />VWP -09 <br />2.8 <br />3.0 <br />2.9 <br />+0.1 <br />-0.1 <br />VWP -10 <br />-1.9 <br />-1.7 <br />-1.8 <br />+0.1 <br />-0.1 <br />The physical locations of the piezometers are shown on the attached Instrumentation Site Plan, <br />Drawing 1. The graph of historical data through 5 -21 -14 is presented for reference as Figure 1. <br />A graph of active piezometers only is presented as Figure 2. <br />Inclinometers <br />Three inclinometers, designated BG05 -04, BG05 -05, and BG05 -07, were installed at CWDA No. <br />2 in August 2005. The inclinometers were installed through the coal refuse and approximately <br />20 feet into the native foundation soils. The physical locations of the inclinometers are shown <br />on the attached Instrumentation Site Plan, Drawing 1. Baseline readings were taken on <br />8/10/05 and subsequent readings have generally been taken quarterly since that time. <br />Displacement curves for the prior nine month period are presented as attachments to this letter <br />for each inclinometer. Axis "A" reflects deformation with depth in the direction of anticipated <br />movement (downslope), while Axis "B" is orthogonal to Axis A. Based on our most recent site <br />Bowie CDWA 2 VWP and Inclinometer Q1 2015 report <br />Project #7131.74111.01 <br />Page 1 of 2 <br />