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As seen on Figure 2. the VWP readings are consistent either with previous recent or historic <br /> readings. Pore pressure readings went down slightly in two piezometers, up slightly in one <br /> piezometer, and stayed the same in two piezometers when compared to the Q2 readings. <br /> Inclinometers <br /> Three inclinometers,. designated BG05-4,, BG05-5,, and BG05-7, were installed at CWDA #2 in <br /> August 2005. The inclinometers were installed through the coal refuse and approximately 20 <br /> feet into the native foundation soils. The physical locations of the inclinometers are shown on <br /> the attached Instrumentation Site Plan (Map 1). Baseline readings were taken on 8/10/05 and <br /> subsequent readings have generally been taken quarterly since that time. Displacement curves <br /> for each of the three inclinometers for the current and the prior three readings are presented as <br /> attachments to this letter in Figure 3. Axis"A" reflects deformation with depth in the direction of <br /> anticipated movement (downslope), while Axis "B" is orthogonal to Axis A. <br /> As described in previous reports, we believe historic displacements indicated on the plots for the <br /> approximate upper ten feet of the inclinometers are likely due to placement of cover soil on the <br /> face of the waste pile during normal operations for maintenance and revegetation. Recent <br /> downslope readings (Axis A) are generally consistent with previous readings. There appears to <br /> be some displacement in the orthogonal direction (Axis B) for inclinometer BG05-5B. In March <br /> 2019 there was no displacement, but in June the displacement was above 14 feet, and in the <br /> recent September the displacement appeared to continue to roughly 42 feet. However, this <br /> displacement is not in the downslope direction, so it is not overly concerning, and may be due <br /> to a systematic recording error. There is no downslope displacement of any of the three <br /> inclinometers. This discrepancy should be evaluated during the next (Q4) reading. <br /> If you have any questions regarding this letter or the instrumentation monitoring at CWDA #2, <br /> please contact me at (907) 562-2000 or Lholland@dowl.cam. <br /> Respectfully Submitted, <br /> DOWL <br /> %V 09Y Vint 4!;% <br /> 40723 <br /> Jeremiah E. Holland,, P.E. <br /> Geotechnical EngineerSl�IVAL, <br /> LJB/JEH <br /> Enclosures: Map 1 — Instrumentation Location Plan <br /> Figure 1 — Active and Damaged Piezometer Data Graph (2005-2014) <br /> Figure 2 — Active Vibrating Wire Piezometer Data Graph (to present) <br /> Figure 3 — Inclinometer Displacement Curves <br /> Bowie CWDA#2 Q3 2019 MP-Indinometer report.docx <br /> Project#7131.74699.03 <br /> Page 2 of 2 <br />