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entries. Drilling of the borehole was covered by the TR0548 submittal. Details for the concrete pad and bulk <br />storage and transfer facilities will be submitted for review and approval as a Minor Revision, prior to installation. <br />The water component includes construction of a reinforced concrete pad and footers, installation of a water tank <br />(6MN Million-Gallon Tank - MR06-210) and associated pumping installation, and drilling of a nominal 13-inch <br />borehole from the surface to the underground workings from the shaft pad above the 6-North Main entries. Drilling <br />of the borehole was covered by the TR05-48 submittal. TCC proposes to construct a steel water tank 85 feet in <br />diameter and 24 feet high designed to hold one million gallons. The tank will rest on a reinforced concrete <br />foundation consisting of a spread-footer, stem wall, and slab floor supported by concrete pilings. Preparation of the <br />tank foundation area will involve grading, compaction, and excavation for the support pilings and spread-footer. <br />Following site preparation, the reinforced concrete pilings and footers will be formed, and poured, followed by the <br />reinforced concrete pad and stem wall. The steel tank will be fabricated in sections which will be placed and <br />anchored on the stem wall. A water-tight liner system will complete the tank installation. <br />A buried 8-inch HDPE line will connect the tank to the water borehole for both filling from and discharge to the <br />mine water system. Pumps (both underground and at the surface) and control sensors and valving will allow for <br />controlled flow in either direction in the supply system. Tank fill sensors and a monitored overflow drain will be <br />installed in the tank to prevent overfilling. The overflow drain line will be installed in the same trench as the water <br />supply and return-line and will drain back to the mine-water handling system. A small 8 x 8 foot pumphouse, will <br />be constructed next to the tank on a concrete foundation to house pumps and valves. Power and/or control <br />communications will be laid in conduit above the waterline connecting the tank and the borehole. <br />The locations for the seven boreholes for project utility components are shown on Maps EX16E-M1 and M2. As <br />shown on Map 23, additional entries will be driven to the south of the 6 North Main entries to connect with the <br />ventilation shaft. These entries will be needed to maximize the efficiency of the ventilation system. The entries will <br />be driven in the same manner as is used in TCC's development work, i.e. continuous miners and shuttle cars. <br />Following commissioning of the shaft, the shaft pad site and access road will be cleaned-up and surface areas graded <br />and dressed. <br />In addition to the direct piped connection to the mine-water system at 6MN, the Million-Gallon Tank will be <br />connected to a water supply line from the 6MN Mine Water Storage Reservoir. The 6MN Storage Reservoir will be <br />used to provide back-up storage for TCC's 10-Right Mine Dewatering Well (also previously identified as the EMD <br />Dewatering Facility), allowing the well to pump continuously at full capacity, providing buffer storage for pump <br />maintenance or failure, and limiting the distance over which the mine water must be transferred. The 6MN Storage <br />Reservoir is designed as a closed reservoir, with no discharge, and provision for adequate operating freeboard to <br />allow for storage of runoff from a small upslope drainage area. Most runoff from the upgradient drainage basin will <br />be captured and diverted around the reservoir by a designed temporary diversion ditch. <br />Water from the 10-Right Mine Dewatering Well, which pumps accumulated mine inflows from a sump in the sealed <br />Eastern Mining District, is pumped to the surface by a 320 HP high-capacity submersible pump, at a rate of <br />approximately 700 gpm. The pump discharge is currently transferred by a series of surface and underground <br />pipelines to the Area 1 Pit in the TCC Mine Facilities Area for use in either coal preparation operations or for storage <br />and subsequent use as a back-up source for the operational mine water system. <br />The 6MN Mine Water Storage Reservoir will be constructed south of the current 6MN Shaft pad and northwest of <br />the NW Mains Ventilation installation. Prior to reservoir construction, sediment control materials (straw wattles or <br />silt fence) will be placed downgradient of the construction area, and an estimated 12,800 cy of topsoil (average depth <br />12-inches) will be recovered and placed in a stockpile approximately 90 feet wide and 600 feet long adjacent to the <br />existing topsoil stockpile for the 6MN Ventilation Shaft Pad. The stockpiled topsoil will be stabilized by seeding <br />with the standard temporary stabilization seed mixture within 6 months following completion of placement, and <br />drainage from the pile will be controlled through placement and maintenance of erosion control material (straw <br />wattles or silt fence) around the stockpile perimeter until effective vegetative cover is established. The reservoir <br />embankment will be an earthen dam constructed of suitable fill material excavated from the reservoir basin <br />(approximately 15,800 cy) and placed and compacted consistent with the engineering design specifications and <br />construction recommendations provided in Exhibit 490, 6MN Mine Water Storage Reservoir - Design Drawings. <br />TR07-61 2.05 - 45.6f 09/26/07