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CWDA No. 2 <br />#01349-0001 <br />01/11/16 <br />0p� <br />0 Huddleston -Berry <br />pu„o� o„xVh,x,rr� wa.v <br />e. <br />Discussion of Inclinometer Monitoring <br />The latest inclinometer readings indicate no significant movements since the last quarterly <br />reading. <br />Vibrating Wire Piezometers <br />Between 2005 and 2012, a total of ten vibrating wire piezometers were installed in CWDA No. <br />2. However, several of the piezometers have been damaged or have otherwise ceased to <br />function. Currently, five of the piezometers are functional. <br />Monitoring of the functioning piezometers was completed by DOWL on December 19th, 2015 <br />and January 8th, 2016. The attached monitoring report prepared by DOWL includes the <br />piezometer monitoring data and the data is summarized in the following table. <br />VWP ID <br />Initial Pore <br />Pressure <br />(psi) <br />09/26/15 Pore <br />Pressure <br />(psi) <br />12/19/15 Pore <br />Pressure <br />(psi) <br />Difference Since <br />Installation <br />(psi) <br />Difference <br />Since Last <br />Reading (psi) <br />VWP-05 <br />6.8 <br />2.2 <br />1.9* <br />-4.9 <br />-0.3 <br />VWP-06 <br />11.3 <br />15.4 <br />15.0 <br />+3.7 <br />-0.4 <br />VWP-08 <br />8.2 <br />9.9 <br />10.0 <br />+1.8 <br />+0.1 <br />VWP-09 <br />2.8 <br />2.9 <br />2.8 <br />0.0 <br />-0.1 <br />VWP-10 <br />-1.9 <br />-1.8 <br />-1.9 <br />0.0 <br />-0.1 <br />*Measured on 01/08/16 <br />Discussion of Vibrating Wire Piezometers <br />VWP-05 <br />VWP-05 was installed on August 3, 2005 near the toe of CWDA No. 2 adjacent to the access <br />roadibench. The pore pressures recorded at VWP-05 have shown some seasonal fluctuations; <br />however, the range of pore pressure changes is fairly small. In general, HBET does not believe <br />that the pore pressures in VWP-05 are cause for concern regarding stability of the gob pile. <br />VWP-06 <br />VWP-06 was installed on June 5, 2009 near the existing top of CWDA No. 2. The pore <br />pressures recorded at VWP-06 have fluctuated since installation. The pore pressures increased <br />following installation until March 2013 and then fell until April 2014. However, between April <br />2014 and August 2014, the pore pressures again increased. This likely reflects the fact that gob <br />placement was occurring in the vicinity of this instrument during the spring and summer 2014. <br />There was a slight decrease between August 2014 and January 2015 which likely reflects the fact <br />that gob placement operations slowed and finally ceased for the winter. A slight increase was <br />reported between January 2015 and March 2015. However, the pore pressures have been <br />decreasing since March 2015. In general, HBET does not believe that the measured pore <br />pressures are an indication of any instability in CWDA No. 2. <br />X:A2008 ALL PROJECTS`01349 -Bowie Resources, LLCA01349-0001 Bowie Mine `200 - GeoAGob 2`lnstrumentation Monitoring'2015'01349-0001 GP2 4thQ 2015 011116.doc 2 <br />