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<br />57. The following comments concern the Theis drawdown calculations: <br />a. Please provide, in the permit application, the input values for the Theis analysis. <br />b. How is T = 0.0207 ftZ (O.155gpd/ft) arrived at? is it an average for the <br />"overburden wells? If so, please specify which wells were used to calculate the <br />average. Please answer the same quesUOn for the Wadge Coal. <br />c. With the new calculations (which should be included in the permit application <br />package) please explain where the input values came from. <br />d. Is the "pit area in water" calculated per pit? <br />e. Item #7 for the revised overburden calculations: The Division calculates a radial <br />distance of 237 feet for the 5-foot drawdown using Peabody's input pazameters. <br />Please verify SCCs calculation. ' <br />f. Page 10, uation 3: The equation appeazs to be inverted, in that the pazameter <br />"u" should be in the denominator rather than the numerator. <br />g. Please submit maps showing how the wet areas were calculated. <br />58. Page 11 and Item #1 of Table 17-22. state that there are no righted or unrighted wells <br />or ponds within the area of mining disturbance. We are awaze of at least two existing <br />ponds in the 5rst five yeaz mining block. Please reevaluate these statements and revise <br />the text accordingly. <br />59. The PHC predicts impacts only for the first 5 years of mining. Please include impact <br />predictions for the life of the mine. <br />60. Page 13 references the water rights augmentation plan that was approved by District <br />Court. Please forwazd copies of the plan and documentation of its approval. <br />61. Page 15: The average pit inflow of 11,254 gpm for the Wadge Coa] and Overburden <br />doesn't seem to agree with the inflow values presented in Table 17-2. Please explain the <br />discrepancy. <br />62. Please include the calculations for the McWhorter pit inflow analysis in the permit <br />application package. <br />63. Page 31: SCC should elaborate on their arrival at a peak TDS concentration for the <br />spoil dischazge. The discussion should include a description of chemical reactions in the <br />unsaturated wne (where the lysimeter samples were collected) and how that coinpazes <br />with conditions expected within the spoil aquifer. This is a critical point, as all of pCCs <br />subsequent calculations of salt loading to the aquifers and surface water bodies are based <br />on the assumption that 4500 mg/1 is a conservative estimate of spoil water discharge <br />quality. <br />64. Page 45: SCC states that the impact of spoil discharge to Armand Draw and Grassy <br />Creek will occur until the ponds are removed and reclaimed. How will the removal of <br />the ponds change or eliminate the impact of the spoil discharge on Armand Draw and <br />Grassy Creek? <br />65. There appears to be an error on Table 17-2, in that the units for transmissivity should be <br />M. Altavilla and G. WenCt 11 January 23, 1995 <br />