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2.04.5 General Description of Hydrology and Geology Referer~ces to other permit sections. No adequacy comment. 2.04.6 Geology Description The general geology and structural geology discussions presented in this section are faii:hful renditions of previously published descriptions of the regional geology. Further the geological hazards mapping presented was performed by Raye Junge of the Colorado Geological Survey. A geological map, a geological hazard; map, and geological cross sections of the permit area are provided. On page 2-04-14, under the "Structural Geology" heading, Bowie Resources Limited (BRL) states; "There is one indicated fault that crosses the southwest corner of the permit area." My examination of Maps 05, 06 and 07, and the geologic cross section included on Map 08, could not discern the location of the fault in question. BRL should clarify the fault's location on the geologic maps and cross sections. As BRL is aware, the Bowie No. 1 (previously the Orchard Valley mine) encountered a number of faults with 5 to 25 foot throws within the upper D-seam which necessitated ramping, particularly within the east mine workings. Faulting of this sort can become a significant consideration for the operating cost of an underground mine. A thorough aerial photographic analysis of the permit and adjacent area might assist in defining the location of potential faults. A brief discussion of the acid generating potential of the Upper B and Upper D coal seams are presented in the text. Supporting chemical analyses are referenced within Exhibit 6 of volume III. Page 2-04-18 of the application states; "It is likely that lime is present in adequate quantities to neutralize the acid forming component in the coal." The limited geochemical analyses of the coal seams provided within Exhibit 6 of Volume III show the Upper B-Seam to vary from 0.4% to 0.01% (average 0.145%) dry weight pyritic sulfur. This data also shows the Upper D-Seam to vary from 0.05% to 0.01 % (average 0.027%) dry weight pyritic sulfur. The data included within Exhibit 6 regarding occurrence of calcium shows minimal amounts of soluble Calcium and Magnesium to be present. in the roof and floor rock. No Calcium or Magnesium data is provided for the two coal seams. No anion analyses, such as carbonate, or acid/base potential determinations are provided for any of the coal., floor or roof materials. I cannot find a basis for BRL's belief that sufficient lime is present within the coal to negate the formation of acid within these coal seams. BRL