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Coal Mine Waste Bank Nos. 1, 2, & 3 Inspections — 3rd Quarter 2017 <br />On September 20 2017, a visual inspection of the Bowie No. 2 Mine coal mine waste banks <br />was performed by the undersigned in accordance with Rule 4.10.2. This inspection includes <br />Gob Pile Nos. 1, 2, and 3. Pile No. 1 is considered inactive. Pile no. 2 is located north of <br />Bowie Road. Pile no. 3 is located south of Bowie Road. <br />I, Tamme Bishop, P.E., have a wide variety of experience in the design and construction of <br />earth fill embankments. Nothing was observed during the inspection that would indicate the <br />piles have a potential for failure. The slips discussed in the 4Q 2016 and 1 Q 2017 report <br />had been regrade to the design contours and show no evidence that would be cause for <br />concern of slipping again. A fair cover of volunteer vegetation has been established. <br />A small area of seepage was seen at the toe of gob pile #2, west of the haul road. There are <br />no windrows remaining on top of gob pile #2. All organic material and topsoil has been <br />removed ahead of the waste bank founding. The diversion ditches were cleaned out during <br />June, 2017 and were in good repair. The upper diversion and lower ditches at gob pile #3 <br />were inspected, and were in good condition, however the upper diversion ditch should be <br />cleaned out during 2017. The lower diversion ditch (J3) had been cleaned out in May. A <br />new seep has been discovered at gob pile #3, north of the east drying area. At this time, the <br />seep will not impact the long-term stability of the gob pile. However, before final placement <br />and compaction of gob in the footprint of the east drying area, an underdrain will be installed. <br />Approval of the underdrain design was incorporated into the permit under Technical <br />Revision No. 105. <br />At gob pile #2, the first bench east of the haul road is covered with soil. The second bench <br />east of the haul road is mostly covered with a subsoil pile. Most of the third and forth <br />benches east of the road are covered with soil. Soil has been placed on most of the second <br />and third benches west of the haul road. <br />There was no coal mine waste was generated from the preparation plant during the quarter. <br />Coal mine waste is to be placed in the piles in approximately horizontal lifts no more than 24 - <br />inches thick. The coal mine waste is dried and then spread and compacted by self propelled <br />sheepsfoot compactors. A total of 41 compaction tests were taken at gob pile #3 during the <br />quarter. There were no compaction tests taken at gob pile #2. <br />The top of gob pile #2 can serve as a drying area for end dumped gob. Gob is to be stacked <br />to a maximum height of 20 feet, with a slope angle up to 1.5h:1v. A 25 -foot buffer zone on <br />the face of the gob pile will be maintained at all times. Gob will be spread and compacted to <br />the currently approved slope configuration as soon as gob and weather conditions allow. <br />The westernmost and easternmost sections of gob pile #3 serve as drying areas for end <br />dumped material. The purpose of the gob drying area is to provide an area for temporary <br />storage of gob for drying purposes. End -dumped gob in the gob drying areas is worked with <br />6e <br />