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TR-42 Adequacy Review Comments BME's response addressed the Division's concerns, but Cross Section B-B', shown on Map 150, is not consistent with the plan view shown. Please revise the cross section. 2. The SEDCAD+ modeling provided by BME does not appeaz to be consistent with the drainage patterns shown on Map 150. The working map provided indicates that some azeas aze routed uphill. The designs for the ponds are based on two watershed azeas per pile, which is inconsistent with the configuration used to design the ditches and with what would be happening on the ground. Please revise the designs to accurately reflect proposed ground conditions. BME indicates that the SEDCAD+ runs include a trickle tube to simulate the ponds being pumped as soon as practicable afrer a storm event. BME indicates the runoff pumped from the ponds would be used for dust suppression. DMG cannot approve the ponds as designed. If the azea received heavy rainfall on a weekend or at a time of mine shutdown when mine personnel are not available to manually pump the pond, it is quite possible that the water level in the pond could rise to the top of the riser. Also, during wet seasons, if the mine roads aze already saturated, BME would not likely be able to use the water for dust suppression since there would already be too much water on the roads. The ponds must be designed so that, in the event that water is up to the level of the riser top, a 10-yeaz, 24 hour precipitation event could be dischazged through the riser while meeting effluent standazds. The SEDCAD+ modeling needs to be revised using this assumption. 4-6. Concerns satisfactorily addressed. - The response indicates that Map 76 includes information on the combined sub-azeas 2-3 and 4. It is not cleaz that this is the case. A revised Map 76 was not included in the most recent submittal (possibly an oversight). The most recent update to Map 76 on file with _ DMG was revised in June, 1996, and submitted on July 10, 1996. TR-42 was submitted - subsequently, in September, 1996. The referenced table on the June, 1996 map appeazs to specify acreages, capacities and time-frames for sepazate sub-azeas 2-3, and 4, rather than a single combined sub-azea 2-3-4, and needs to be appropriately updated. 8-11. Concerns satisfactorily addressed.