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Quarterly Inspection Report -Refuse Pile April 5, 2019 <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 March 29, 2019 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 77,522 tons of waste coal during the <br />month of January 2019: approximately 78,681 tons during February 2019: and approximately 68,062 tons <br />during March 2019. It is our understanding that the fines being produced at the wash plant, which consists <br />of approximately 10 to 20 percent of the total materials being produced, are being pumped underground <br />into 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#1) was measured at <br />57.16 feet below the existing ground surface (bgs) on January 10", at 57.13 feet bgs on February 22nd and at <br />57.10 feet bgs on March 15' of 2019. The water level in the eastern monitor well (RW92) was measured at <br />56.18 feet bgs on January 10"i, at 56.15 feet bgs on February 22nd and at 56.1 feet bgs on March 15t" of <br />2019. An additional monitor well (RW#3) was constructed at the southeast end of the 1st bench in new <br />Expansion Area in June of 2014. The water level in the expansion area monitor well (RW#3) was dry when <br />checked on January l Od', February 22nd and March 15°i of 2019. <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(1 1)(b), 4.10.2(2)(a) and <br />4.10.2(2)(b). <br />NWCC, Inc. <br />