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Ms. Christine Johnston <br />Mountain Coal Company <br />Page 3 <br />September 6, 1996 <br />(under flow) also refers the reader to appendix A, which is incorrect because <br />Appendix A is flow data for Minnesota Creek. Please check the data <br />presented in Table D-9, and if appropriate, provide a revised report table. <br />6. Well GB-1 was installed in 1995 to replace well SG-1. Why was the new well <br />installed at a different elevation and installed with a different slotted interval, <br />if it was designed to be a replacement well. GB-1 was installed at an <br />elevation 10 feet lower than SG-1 and only installed to a depth of SO feet with <br />the slotted interval from 10'-50'. The original SG-1 monitored a completely <br />different subsurface interval (perforated interval 63'-84'). Please provide an <br />explanation for the rationale for designing and installing the replacement well <br />differently. No revised report page is necessary. <br />7. Please revise the text under Groundwater Inflows to provide duration of <br />inflows or other information to support the calculation of natural inflow <br />provided in Table 1.6-1. <br />8. On Table 1.6-1, item j states that 4.0 acre feet were retained in the mine <br />behind 1-5 NW long wall panels. If this is the case, then the 4.0 acre feet <br />should not be included in item r as part of the total mine water outflow (ie., <br />r=i+j+k+l+m should not include item j). Please check this calculation, and <br />if appropriate, provide a revised Table 1.6-1. <br />9. If water is being discharged in the mine behind 1-S NW long wall panels, then <br />according to Rule 4.05.16, discharges will be discharged as a controlled and <br />identifiable flow and ultimately treated by an existing treatment facility. <br />Please provide an explanation of the water retained in the mine, identifying <br />the flow, mechanisms used to control the flow, and provide an explanation of <br />the ultimate disposition of the water. If appropriate, please add a section to <br />the report detailing discharge of water underground. <br />10. Water quality of mine inflows cannot be represented by discharges from MB-1 <br />and MB-2R. As stated, on page 22 under Mine Water, "any discharge from <br />ponds would normally be dominated by water quality characteristics of <br />disturbed area runoff'. In order to get adequate water quality samples of the <br />mine water, the Division recommends that samples for mine water quality be <br />collected at the end of the pipe prior to discharge to MB-1 or MB-2R. <br />11. Numeric effluent limitations for Outfall 007 are defined as 30-day averages <br />or 7-day averages for 5-Day BOD, Total Suspended Solids, and Fecal <br />