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Drilling Methods and Equipment: Exploration holes will be established with arubber-tired truck- <br />mounted air/foam rotary drill. Drilling mud may be employed in the drilling medium. Previous <br />drilling activities in the immediate area have not encountered water-bearing formations producing any <br />appreciable quantities of water from the strata overlying the coal seam of interest. Both the <br />Twentymile Sandstone and Wedge Overburden have been documented to contain water, however, <br />neither typically exhibits significant flow at the surface. Drill hole depths projected for each site are <br />specified on 1999 NOI Table 1. After drilling [he holes will be logged with a standard suite of <br />geophysical data logging instruments. No holes will be developed as water wells. Exploration holes <br />will be sealed with cement grout installed with the dulling rig to within 3' of the surface. Drill cuttings <br />will be used to backfill the uppermost 3' of each hole. <br />In reference to the holes surface casing will be set 10' below bedrock to ensure drilling fluids are not <br />lost in the surficial soils. The surface casing will be grouted in place and then the hole will be <br />advanced as per normal methods. The surface casing at both sites will have a threaded surface collar <br />to allow for quick shut in of the hole in case significant Flows are encountered. <br />Holes PDH9901 and PDH9902 are relatively shallow (750' TD) as compared to other holes drilled at <br />the property and mainly will be advanced through 500 feet of marine shale that immediately overlies <br />rite Wadge Overburden unit. Therefore, TCC does not anticipate encountering any large volume of <br />water. The Wadge Overburden may produce a minor amount of water that can be contained within <br />the mud pits. <br />The coal will be cored and the hole geophysically logged. Upon completion of the coring and logging <br />the hole will be tremie grouted through and twenty feet above the Wadge Overburden. From that <br />point up it will either be grouted or backfilled with cuttings to within ten feet of the surface. The <br />interval from ten feet to within three feet of the surface will be grouted and then the remaining three <br />feet will be backfilled with soils. The surface casing will be cut off three feet below the surface or it <br />maybe removed entirely from the site. The hole will be mazked as discussed previously. <br />Seismic Line: Twentymile is planning to conduct a limited seismic investigation. This program will <br />use the classic approach of drilling holes, setting off charges, and placement of geophones and <br />instruments for recording the data. With the advances in computer technology, TCC is optimistic <br />better resolution of the signal can be obtained and this will be used to define the fault. <br />The seismic will establish three lines approximately 2 miles total length. The southernmost line trends <br />about S60W and extends 1,320 ft. from Nl/2 Sec 17, TSN, R86W to the SWl/4 Sec 22, TSN, R87W. <br />The second line also extends 1,320 ft. on a similar southwesterly trend. It begins near the center of <br />Sec 2, TSN, R86W and terrninates in the SWl/4 Sec 7, TSN, R86W. The third line trends 1,320 ft. <br />westerly from near the center of Sec 2 to the W 1/4 Sec 5, TSN R86W as shown on the 1999 Notice <br />of Intent seismic map (seismic99). Shot holes will be established on 125 foot centers. The geophones <br />may extend 1,320 feet past the ends of the shot line. Drill holes will be approximately 20 to 22 feet <br />deep and will have a nominal diameter of 4.5 inches. The cuttings from the drill holes will be mixed <br />with bentonite chips to be used as stemming over a 1 pound biodegradable charge that will be placed <br />in the bottom of the hole. The holes will be drilled with a small auger drill rig mounted on tires or <br />tracks. There are no plans to construe any roads to aid in the drilling of the holes. The rig is <br />sufficiently mobile to eliminate the need for road building activities. All fence damage will be repaired <br />immediately upon completion of the seismic lines. Upon completion of the program the shot wires, <br />marker stakes, survey flagging, left over supplies, all trash, geophones and cable will be recovered. <br />Based upon the limited depth of the holes and the Eact that the cuttings will be used to backfill the <br />holes prior to shooting, no further reclamation work is planned. <br />Reclamation Plan: Reclamation activities will begin once mud pits are sufficiently dry to allow <br />regrading of each site to occur. Materials excavated for the mud pits will be redistributed over the <br />MONTGOMERY WATSON June 1999 <br />Twentymile Exploration NOI draft <br />