2015-10-19_REPORT - C1996083 (2)

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4 October 8, 2015 970-249-6828 ■ 800-865-9847 (fax) ■ 222 South Park ■ Montrose, CO 81401 ■ wew.dowl.com Alaska ■ Arizona ■ Colorado ■ Montana ■ North Dakota ■ Oregon ■ Washington ■ Wyoming Huddleston -Berry Engineering and Testing, LLC 640 White Avenue Grand Junction, CO 81501 Attention: Mike Berry, PE SUBJECT: Third Quarter 2015 Summary of Inclinometer and Active Vibrating Wire Piezometer Data through October 3, 2015, Bowie Mine No. 2, Coal Waste Disposal Area No. 2 Dear Mr. Berry, DOWL has conducted quarterly monitoring of inclinometers and vibrating wire piezometers at Coal Waste Disposal Area No. 2 (CWDA No. 2) for Bowie Resources, LLC (Bowie). This report is intended to cover the time period of July through September 2015. VWP data was obtained on 9-26-15 and inclinometer data was obtained on 9-26-15 and 10-3-15. Per DRMS and your instructions, vibrating wire piezometer readings for all active piezometers are taken quarterly along with inclinometers. VWPs 06 and 08 were read monthly for July and August per DRMS request as noted in Table 1. Vibratina Wire Line Piezometers Table 1. Summary of VWP Pore Pressures VWP ID # Initial Pore Pressure (psi) 6/26/15 Pore Pressure (psi) 8/01/15 Pore Pressure (psi) 9/26/15 Pore Pressure (psi) Difference Since Installation (psi)si Difference Since Last Reading VWP-05 6.8 1.8 2.2 -4.6 +0A VWP-06 11.3 15.7 15.4 +4.1 -0.3 VWP-08 8.2 9.8 9.9 +1.7 +0.1 VWP-09 2.8 2.9 2.9 +0.1 0 VWP-10 -1.9 -1.8 -1.8 +0.1 0 The physical locations of the piezometers are shown on the attached Instrumentation Site Plan, Drawing 1. The graph of historical data through 5-21-14 is presented for reference as Figure 1. A graph of active piezometers only is presented as Figure 2. Inclinometers Three inclinometers, designated BG05-04, BG05-05, and BG05-07, were installed at CWDA No. 2 in August 2005. The inclinometers were installed through the coal refuse and approximately 20 feet into the native foundation soils. The physical locations of the inclinometers are shown on the attached Instrumentation Site Plan, Drawing 1. Baseline readings were taken on 8/10/05 and subsequent readings have generally been taken quarterly since that time. Displacement curves for the prior nine month period are presented as attachments to this letter Bowie CDWA 2 VWP and Inclinometer Q3 2015 report Project #7131.74111.01 Page 1 of 2