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enclosed by a chain link fence 6 feet high with 1 foot of barbed wire overhang. Foundations for the <br />• circuit breaker, transformer and switchgear are reinforced concrete slabs on grade. <br />There are unit substations at the preparation plant, "D" Portal, and at the transfer structures for the <br />overland conveyor. The unit substations are enclosed by chain-link fence as previously described <br />with similar foundations for transformers and switchgear. <br />Power for the overland conveyor including the railroad loadout facility comes from the main <br />substation at the mine site. One additional 13.8-kV feeder breaker is installed in the switchgear <br />line-up for 13.8-kV mine distribution. This circuit supplies a new 13.8-kV single wood pole line <br />constructed parallel to the conveyor flights and terminating at the loadout substation. The line was <br />installed on the east side of the corridor east of the conveyor and access road. Access during <br />construction was via the conveyor maintenance road. <br />The 12.5-kV (13.8-kV) power line was constructed prior to any construction work at either portal as <br />this power was used to operate an air monitoring apparatus. Distribution lines were of single pole <br />with a crossarm. The height of the poles was determined by required clearances over obstructions, <br />roadways, and crossings. Pole setting (depth of setting, feet) varied based on the length of the pole. <br />Some typical settings were 5.5 feet, 6 feet, and 6.5 feet for pole lengths of 30 feet, 35 feet, and 40 <br />feet, respectively. Where the poles are supporting unbalanced stresses, from dead-ending or <br />change of direction, guying and anchors were used. Existing soil removed by auger or hand was <br />• used for backfill. <br />The 138-kV line and the associated substations were constructed prior to mine operation. After <br />mine operations cease, the 13.8-kV line and all substations will be dismantled and foundations <br />removed or buried on site. The 138-kV line will remain, as it will eventually connect with another <br />138-kV line north of the permit area. By connecting the two transmission lines, the overall reliability <br />of Moon Lake Electric Association's 138-kV distribution system will be improved. <br />A diesel powered emergency generator was installed in 2009 to power the mine fan in case of line <br />power failure. The emergency generator is located adjacent to the mine fan in a self contained <br />enclosure. <br />0 Minor Revision #141 (7/2009) IV-2 5