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Quarterly Inspection Report -Refuse Pile July 9, 2018 <br />Twentymile Coal Company-Foidel Creek Mine <br />A seepage area at the toe of the northeast end of the refuse pile expansion area, approximately 30 feet <br />northwest of the outlet of the underdrain, developed in fall 2014. At the time of our observations, the <br />seepage was surfacing at the toe of the slope and flowing into the drainage from the undrain outlet then into <br />the existing pond east of the Refuse Pile Expansion Area. The discharge was clear, with no evidence of <br />sediment. No signs of washout, slumps or slope instability were observed at this time. The seepage area <br />will be monitored during future inspections and noted in our inspection reports. Photographs of the seepage <br />area taken at the time of our inspection on June 29, 2018 are attached. <br />Based on our observations, the surface drainage conditions, generally appeared to be adequate across the <br />top and sides of the pile. Based on our observations, we did not observe any signs of instability, structural <br />weakness or hazardous conditions at the refuse pile. <br />We were advised that the wash plants had produced approximately 184,921 tons of waste coal during the <br />month of April 2018: approximately 189,129 tons during May 2018: and approximately 150,050 tons <br />during June 2018. It is our understanding that the fines being produced at the wash plant, which consists of <br />approximately 10 to 20 percent of the total materials being produced, are being pumped underground into <br />the mine. <br />We were previously informed by Brian Watterson of Peabody that all of the original monitor wells installed <br />in the Refuse Pile were destroyed in July 2012. Two new monitor wells were constructed in Area 1 of the <br />Refuse Pile in December 2013. NWCC was provided monthly monitor well readings for this quarter by <br />Miller Water Monitor Service, Inc. The water level in the western monitor well (RW#I) was measured at <br />57.23 feet below the existing ground surface (bgs) on April 24th, at 57.14 feet bgs on May 9n' and at 57.27 <br />feet bgs on June 12" of 2018. The water level in the eastern monitor well (RW#2) was measured at 56.25 <br />feet bgs on April 24th, at 56.18 feet bgs on May 9°i and at 56.32 feet bgs on June 12'h of 2018. An <br />additional monitor well (RW#3) was constructed at the southeast end of the I" bench in new Expansion <br />Area in June of 2014. The water level in the expansion area monitor well (RW#3) was dry when checked <br />on April 24"i, May 9a' and June 12'h of 2018. <br />Based on our limited observations, it appears that the pile is currently being constructed and maintained in <br />general accordance with the project specifications and plans submitted under 2.05.3(8) and that the <br />potential hazard to human life and property at the site in its present condition is minimal. This report fulfills <br />the quarterly inspection requirements as specified by Rules 4.09.1(11)(a), 4.09.1(11)(b), 4.10.2(2)(a) and <br />4.10.2(2)(b). <br />NWCC, Inc. <br />