2008-01-11_PERMIT FILE - C1982056A (2)

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Electrical Distribution Electrical power is provided to the mine site by Yampa Valley Electric Association. Sixty-nine thousand (69KV) volt power, passes through a metering station and into a 3,750 KVA substation, as shown on Map 24, Surface • Facilities. An additional transformer and switching gear were installed at the existing substation. The transformer and switching gear were placed on a concrete pad, and 6 to 10 powerpoles were installed to handle distribution requirements. The existing fence was extended to enclose the new transformer and poles. It was lengthened by about 21.5 feet on the east side and 15 feet on the west side. Currently, power is converted by transformer from 69 KV to 4,160 V for distribution to the surface, and from 69KV to 12,470 V for distribution underground. A substation measuring 100 x 50 feet, and consisting of a transformer pad, transformer(s) and associated electrical equipment, along with a connecting powerline were constructed to supply power to the advancing underground operations. The substation is shown on Figure 17, Substation Plan View, with the location of the substation and powerline shown on Map 39, Substation and Powerline Location. A 100 KVA transformer measuring 2 x 2 x 1.5 feet is located on the east side of the third office trailer to provide power to the trailer. The transformer location is shown on Map 24, Surface Facilities. Supplemental grounding for the four substations is provided by four 100-foot wires extending radially from the comers, buried to a depth of 5 feet. Supplemental grounding is also provided for a total of 12 powerpoles by means of two 50-foot wires, buried to a depth of 5 feet, extending, to the sides of the poles. The associated disturbance is minimal and required no additional sediment control. Locations of the affected powerpoles and substations aze shown on Maps 39 (Substation and Powerline Locations) and 24 (Surface Facilities). The powerline to supply Washplant I runs from the existing 69KV line to the Washplant site as shown on Map 24, Surface Facilities. The powerline runs overhead from the existing powerline to a point just north of Haul Road B where it is buried. Powerline construction required the installation of five new powerpoles. • Power for the Eastern Mining District (EMD) vent shaft is provided by anabove-ground 3-phase 12,470 volt line. The line runs west 8,200 feet from a switch box at the Mine 3 Warehouse. The line has approximately 28 poles. Installation occurred over atwo-week period, in early winter. The locations of all proposed powerlines for the EMD are illustrated by Figure 16C. A 7,200 volt powerline supply for the EMD Dewatering Borehole runs from Substation No. 2 approximately one mile east-northeast to the site. The line required 18 to 20 powerpoles. Installation occurred in early winter, over a two-week period. The line is buried for 250-350 feet across the right-of--way of the 1 ] 0,000 volt WAPA line and the two 245,000 volt lines. A rubber-tired trencher was used to dig an 8-inch wide trench 2-3 feet deep. The soil was replaced in the trench immediately following placement of the line. A short 240 volt powerline runs northwest from the County road to the location of the settling ponds. This line is approximately 600 feet long and installation required 2-3 poles. A 400 foot extension off this distribution line (requires 3 powerpoles) will supply power to the Fish Creek Ventilation Shafr Dewatering Borehole. A fiber-optics line was installed from the coal lab to the weigh-station located on the railroad tracks. This section of the line is approximately 900 feet long and required installation of 3-4 poles. The poles were installed on previously disturbed ground adjacent to an existing road. The line extends in two directions from the lab; south to the office complex; and west to the loadout facilities. Existing poles were utilized to carry the cable to these locations. One additional pole was needed on disturbed ground adjacent to the existing Overland Conveyor. The locations of the proposed poles are shown on Map 24, Surface Facilities and Freshwater Systems. TCC utilizes the existing road system where possible to establish powerlines. TCC does not intend to develop roads to facilitate access along the line unless poor ground conditions warrant. In the event further preparatory work is required, the available topsoil, usually 24 inches, is windrowed to the side of the road MR07-216 2.05-46 05/28/07