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Huddleston Berry Engineering & Testing (HBET) prepared a stability analysis <br />dated November 21, 2014 to substantiate a request for a variance to the <br />approved slope angle construction at gob pile #1. The report demonstrates that <br />gob pile #1 is stable with a small section (0.1 acres) of the pile constructed at <br />1.5H:1V. <br />The Operator commits to having a qualified third party geotechnical firm perform <br />monitoring and testing. Monitoring will consist of observations of the <br />geotechnical aspects of the construction to determine if any unusual or <br />unexpected conditions are encountered. Testing will include compaction tests <br />and periodic strength tests. Results of the tests and any observed unusual or <br />unexpected conditions will be submitted to the DRMS with the quarterly <br />inspection reports. <br />The quarterly reports will also include a summary of instrumentation monitoring <br />on coal mine waste pile number 2. This report will include a discussion of the <br />inclinometer data and the vibrating wire piezometer data. The inclinometer data <br />will determine if there are indications of deep-seated instability. The vibrating <br />wire piezometer data will determine if the measured pore pressures are relatively <br />stable and consistent with the September 22, 2008 stability analysis performed <br />by Buckhorn Geotech, Inc. <br />The Operator commits to having a geotechnical engineering firm continue <br />instrumentation monitoring, at a minimum, once per quarter. Additional <br />inclinometers and vibrating wire piezometers may be installed at the discretion of <br />the geotechnical engineering firm. <br />Five vibrating wire piezometers were installed in June 2005 (VWP-01 through <br />VWP VWP-05). Of the first five VWP's installed, only VWP-05 is currently in <br />operation. It is likely a short developed and damaged the cables. Three <br />additional wire piezometers (VWP-06 through VWP-08) were installed in June <br />2009. VWP-07 has also ceased to function. Two more piezometers were <br />installed in May 2012 (VWP-09 & VWP-10). Please see the location of the <br />piezometers shown on Figure 1. As progress continues on the gob pile, every <br />effort will be made to not damage piezometers. However, if they are damaged, <br />they will be repaired or replaced as soon as possible. <br />TR -97 _19- 11/14 <br />