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Memo to Tony Waldron <br />Bowie IJO. 2 Geotechnical Adequacy <br />page 2 <br />should expand upon its conclusion regarding the acid forming potential of the <br />upper E3-seam and upper D-seam Williams Fork coals. <br />2.05.2 Operation Plan - Estimated Area for Life of Operations <br />The pn~sentation in this section is straight forward. BRL will initially mine the <br />D-2 (uF~per D) seam using room and pillar techniques. Approximately 1000 acres <br />of D-2 coal is minable within the permit area with another 3,500 acres of <br />adjacent federal coal. Mining during the initial five-year permit term will <br />occur only within the D-2 seam. Later BRL intends to ramp down to the B-2 <br />(upper B) seam, where 800 acres of minable coal exists within the permit area, <br />with another 4,600 acres of potentially minable adjacent federal B-2 seam coal. <br />The maximum anticipated production would be 2,000,000 tons per year. <br />This section is geotechnically adequate. <br />2.05.3 Operation Plan - Permit Area <br />2.05.3(1) Production Methods and Equipment <br />BRL proposes to mine a maximum of 10 feet of coal in the D-2 seam using room <br />and pillar methods. Development mining will be confined to the upper 8 to 10 <br />feet of the seam and will leave 3 feet of roof coal. Retreat mining will recover <br />another 2 to 4 feet of bottom coal. Three entries will enter the reserve via <br />portals. Underground, five or more entries will be used. Appropriate barrier <br />pillars ~Nill be retained between panels, panels and submains, and panels and <br />mains. Partial pillar extraction upon retreat will be used to maintain safe <br />working conditions. Entry spacing will range between 50-feet and 120-feet, <br />while cross cut spacing will range from SO-feet to 150-feet. I suspect that the <br />stated ranges of underground entry and cross cut spacing are to vague to allow <br />projection of subsidence consequences. I will revisit this issue under the <br />subsidence predictions in 2.06.5(6). <br />Map 14~, entitled "Mine Plan", depicts the "Possible Fault" as intersecting the <br />three mains at the portal location. I suspect this will cause some operational <br />