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A <br />1` <br />Figure 2.04-39ii is misleading because it shows the outcrop of the H and C <br />seams to be above the level of the North Fork of the Gunnison River. Amore <br />representative cross section of the Sanborn Creek Mine azea should be <br />submitted to show that the B and C seams aze below the level of the River in <br />the majority of the proposed mine azea. <br />The drill logs of SC-1, SC-2, SC-3 should be submitted as a correlation <br />section similar to DF-2662-11 located in the original Somerset Mine permit <br />application. In addition, water levels and the elevation of the North Fork <br />also should be shown. <br />There seems to be a contradiction between two sections of the permit <br />application, Page 2.05-46ii states that "Drill hole monitoring points SC-1 <br />and SC-2 are designed to monitor the water level and quality of the water in <br />the Rollins Sandstone, which is 40 to 50 feet below the B-Seam. Page 2.04-39i <br />states that "There should be no seepage up onto the Sanborn Creek Mine H-Seam <br />floor from the Rollins Sandstone Aquifer even where the piezometric levels <br />are higher than the mine workings due to the intervening 8.5 feet of <br />relatively impermeable shale bed." The two discrepancies of thickness's of <br />interburden between the Rollins Sandstone and the B-Seam should be rectified <br />and explained. <br />What is the piezometric surface of the Rollins Sandstone mentioned on page <br />2.04-39i and where is the pie2ometeric water level of the Rollins higher than <br />the mine working? Where was this information obtained? This can be submitted <br />as a map. <br />A review of the Somerset Mine inflow study E8-3361, submitted in 1988, showed <br />that most of the inflow into the underground mine was from cracks or faults, <br />most notably a fault encountered in the northwestern portion of the mine area <br />that produced 120 gpm. The drainage pattern of the the North Fork of the <br />Gunnison River watershed in the azea of the mine is known to be fault and <br />fracture controlled. A map submitted by the Mt. Gunnison Mine in their permit <br />application (Exhibit 2.7.58 , portion attached to this review) shows the <br />location of surface fractures in the southern portion of the proposed Sanborn <br />Creek Mine. I noted many fractures in the Coa! Gulch Drainage. Does the <br />Somerset Mine anticipate encountering any of these faults underground and how <br />much inflow can be expected if they contain water? Can these faults form a <br />conduit from which water can flow from the North Fork of the Gunnison River <br />or Rollins Sandstone into the mine? Should these faults be encountered how <br />does the mine plan to handle them? Would it be possible drill a water <br />monitoring well in the location of the greatest number of these faults at the <br />Coal Gulch area and run a pumptest to confirm the mines statement of probable <br />hydrological consequences that maximum inflow into the mine will not be more <br />than 237 gpm? <br />On page 2.04-39i of the permit application the operator uses hydrologic <br />characteristics that he claims are "typical values for coal". The operator <br />should reference his source for these values. <br />Page 2.04-39ii states that "the mine adjacent to the coal outcrop is assumed <br />to be in hydrologic contact with the rechazge source of the North Fork of the <br />Gunnison River".The following sentence states that "the water encountered in <br />2 <br />