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vehicle weight approximately 17,000 pounds). The drilling contractor will also <br />provide a trailer- mounted air compressor to power air rotary and pneumatic Down <br />the Hole Hammer (DTHH) tooling. <br />The drilling subcontractor will provide up to two days of dozer and operator time <br />to improve access to select drilling locations. The drilling subcontractor currently <br />plans to use a Caterpillar D5 dozer or equivalent. <br />1.2 Investigatory Drilling <br />Drilling will be conducted on a grid pattern with approximately 200' centers at <br />the direction of the DRMS PM, starting in the north east portion of the project <br />area. The first line of boreholes will be developed from northeast to southwest, <br />approximately perpendicular to strike. This will give the first indication of <br />burned and unburned coal and the depth of the coal seam(s), and aid in the <br />location of the remaining boreholes throughout the project area. If determined <br />necessary, the drill hole spacing will be reduced to 100' and again to 50', as <br />directed by the DRMS project manager. <br />Drill holes will be advanced using pneumatic DTHH tooling, and all cuttings will <br />be logged by a Shannon & Wilson geologist to provide a stratigraphic record of <br />the borehole. <br />All drill holes will be a nominal four inch (4 ") diameter. An estimated 25 -50 drill <br />holes will be completed, not to exceed 4,000 lineal feet of depth. Drilling will be <br />completed in the Lewis Shale and Williams Fork Formations, which consists of <br />- shale, sandstone, coal, mudstone, and siltstone. <br />Approximately 10 boreholes which encounter open mine workings will be <br />completed by installing slotted two inch (2 ") diameter steel casing into each <br />completed hole. The casing will be slotted through the mine opening interval. A <br />gas torch will be used in the field to cut the slots. Casing joints will be threaded. <br />All casings will be grouted into place. Metal baskets will be installed to contain <br />annular grouting materials above the mine opening. A steel threaded cap will be <br />fitted to the top of the casing to reduce the potential for atmospheric <br />corrununication with the mine opening. <br />1.3 Wireline Rock Coring <br />Core drilling will occur on the north and south extents of the project area, to assist <br />in correlation of stratigraphy across the site. Up to 300 feet of NQ (2 ") core will <br />be drilled in 2 -3 holes using water to circulate drill cuttings. Shannon & Wilson <br />will provide field observation and core logging. The Shannon & Wilson field <br />geologist will box the core onsite. <br />1.4 Install Down -Hole Thermometers <br />The DRMS project manager will provide all supplies and equipment necessary to <br />install approximately 1,000 feet of thermocouple wire and 10 Type K male <br />connectors in those holes completed with casing. Approximately 10 of the drill <br />2 <br />