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J "~ <br />4. P&M submitted a SEDCAD+ Model for the Moffat Final Pit Ditch. A CLrve <br />Number (CN) of 81 was used by P&M in the model for the entire watershed. <br />According the Soils Map and information in the permit application, a "C" type soil <br />is primarily on site. The pit area, and entire watershed, is considered to be <br />completely disturbed. The United States Soil Conservation Service; Technical <br />Release No. 55 (TR-55) indicates that newly disturbed areas with "C" type soils have <br />a CN between 86-91 (newly topsoiled areas). Please inform the Division how P&M <br />derived a CN of 81 for the disturbed areas. <br />5. Exhibit 3.4~ titled, Moffat Post Mining Drainage, was submitted under this technical <br />revision. The current Exhibit 3.4~ in the permit is titled, Typical Mining & <br />Reclamation Cross Section D-D'. It appears that the submitted Exhibit has been <br />mis-labeled 3.4-4, and will replace the wrong map. Please clarify this discrepancy <br />with the Division. <br />6. Moffat Down Drain #1 and #2 appear to have a meandering channel down the <br />reclaimed slope. Exhibit 3.4-4 depicts a straight channel down the reclaimed slope. <br />Please revise Exhibit 3.4-4 to accurately reflect the meandering pattern of the <br />channel. <br />Non-related Hydrology questions; <br />7. The revised page 3.4-2 states that non-salvageable materials removed from the mine <br />facilities will be placed in pit for final disposal. Under Rule 4.11.4 this material is <br />considered anon-coal waste, and should be treated as such. The operator has not <br />adequately addressed Rule 4.11.4 regarding non-coal waste disposal in the Moffat Pit. <br />cc: Larry Routten <br />c:\wp51\misc\951208 <br />m:\coal\esc\951208 <br />