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S • <br />Bowie No. 2 Mine <br />Coal Mine Waste Bank Nos. 1, 2, & 3 Inspections — 2nd Quarter 2017 <br />On June 29, a visual inspection of the Bowie No. 2 Mine coal mine waste banks was <br />performed by the undersigned in accordance with Rule 4.10.2. This inspection includes Gob <br />Pile Nos. 1, 2, and 3. Pile No. 1 is considered inactive. Pile no. 2 is located north of Bowie <br />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. <br />A small area of seepage was seen at the toe of gob pile #2, west of the haul road. The <br />windrows on top of gob pile #2 had been spread on top of gob pile #2. All organic material <br />and topsoil has been removed ahead of the waste bank founding. The diversion ditches <br />were cleaned out during June, 2017 and were in good repair. The upper diversion and <br />lower ditches at gob pile #3 were inspected, and were in good condition, however the upper <br />diversion ditch should be cleaned out during 2017. The lower diversion ditch (J3) had been <br />cleaned out in May. A new seep has been discovered at gob pile #3, north of the east drying <br />area. At this time, the seep will not impact the long-term stability of the gob pile. However, <br />before final placement and compaction of gob in the footprint of the east drying area, an <br />underdrain will be installed. Approval of the underdrain design was incorporated into the <br />permit under Technical 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 />All of the coal mine waste was generated from the preparation plant. Approximately 2,821 <br />tons of gob were hauled during the quarter with 100% of the gob going to gob pile #2. Coal <br />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. No compaction tests were taken at either gob pile #2 or #3 during <br />the quarter. <br />The top of gob pile #2 serves as a drying area for end dumped gob. Gob is to be stacked to <br />a maximum height of 20 feet, with a slope angle up to 1.5h:1v. A 25 -foot buffer zone on the <br />face of the gob pile will be maintained at all times. Gob will be spread and compacted to the <br />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 />-1- <br />