2016-05-19_PERMIT FILE - C1982056 (10)

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Twentymile Coal, LLC SOW — 9 East Bleeder Exhauster Borehole August 6, 2015 10. 16" OD — Exhauster BH Pipe: a. Recommended method of drilling to minimize water inflow — flooded reverse drilling. b. This borehole will also intersect the caved areas with rock rubble of the previously mined Wadge seam longwall panel at approximately 960' to 975' of drilling depth. c. Drilling to the total depth of 1150' shall intersect the coal in an area that has not been underground mined. d. Drilling of the Is' smaller BH will provide an indication of water inflows for this 2nd BH. e. Because of the possibility of the BH producing water, the surface casing for this BH should be oversized to approximately 32" OD as appropriate for the potential of drilling and reaming to a 30" diameter hole to accept a 24" OD schedule 40, weldable or T&C steel pipe to seal off the water. /r f. This first BH shall first be drilled to an approximate diameter of 22", hopefully to the full depth of l 150' without encountering significant water inflows. g Should water not be encountered, the 16" OD, schedule 40, weldable or T&C steel pipes should be installed and grouted in place to a depth of approximately 1150. h. Sealing off water Option l — Should water be encountered — assume this to be at a depth of 700' for bidding purposes: i. In lieu of casing to seal off the water, spot a cement plug at the water inflow interval and drill out the cement plug. i. Sealin2off water Option 2water Option 2 - Should water be encountered and the Option 1 cement plug not seal off the water - assume this to be at a 700' depth for bidding purposes — the 22" hole should then be reamed to a 30" diameter to the 700' depth. j. A 24" OD, schedule 40, weldable or T&C steel casing would then be installed and grouted to seal of off the water. k. Assuming 700' of 24" OD, schedule 40, weldable or T&C steel pipe is installed and grouted to seal off the water, drill the remaining depth to the bottom of the Wolf Creek seam at an approximate diameter of 22". I. Install and grout off approximately 1 ] 50' of 16" OD, schedule 80, weldable or T&C steel pipe. m. TC will provide all steel pipe except the surface casings. 11. This hole will not be directionally drilled. 12. The contractor shall provide for all compressed air and water delivery needs. 13. Water will be available from a stock pond located just within 1 mile and just SE of the proposed drilling site. 14. An oversized cuttings pit will be provided for the drill cuttings. 15. Contractor shall provide the size(s) for any drilling fluid pits. 16. After each site's drilling is complete, TC will arrange for pumping out and hauling away of any waters left in the cuttings pit. 17. The cuttings pit will be dried and leveled off before the site is reclaimed. 18. TC will be responsible for the final reclamation of the site pad. General Provisions Technical questions should be addressed to Michael Berdine at (970)-870-2782 or Jon Bobbera (970)-870-2789. Contractor to provide a detailed, itemized bid on all aspects of this scope of work the Contractor intends to perform. TC prefers a complete packaged bid from each Contractor. Contractor to provide time line for completion of work outlined in this document. The winning bidder will receive a "not to exceed" amount Purchase Order. It is anticipated that MSHA will require us to remove all persons from the mine while drilling tools are advanced, starting 50' above the original Wadge seam roof (-935' drilling depth) and until the drilling intercepts the bottom of the Wolf Creek coal seam. TC will work with the contractor to schedule this portion of the drilling such that it happens near a shift change. The contractor's quote should therefore account for about 20 hours of standby time to allow for the removal of all persons from the mine on multiple occasions. Contractor must maintain all equipment and materials on the provided pad, including drill cuttings and drilling water. Nothing can leave the 200' by 200' site pad. ttachments: 1. Exhibit 1 — Location Drawing 2. Exhibit 2 — Typical Lithology Bleeder Exhauster BH SOW 9 East 080615.doc Page 3