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~) years 2 and 3, the pit will pump 792 acre feet and in year 4, approximately 515 acre feet will be pumped. Almost all of this amount will be pumped into a ditch leading to the White River, although 200 gallons per minute is planned to pump into nearby wetlands to the north and west of the pit to ensure that they do not dry up as a result of the pumping drawdown. Pumping will begin after approximately 2/3 of Phase 2 has been mined, which is estimated to be approximately two years after mining commences. Currently there is no plan to monitor whether 200 gpm will be sufficient to protect the wetlands; it is the opinion of Greg Lewicki and Associates that 200 gpm will be sufficient to protect the adjacent wetlands based on our experience with the Piceance Pit, DRMS Permit No. M-2001-077, which is less than two miles away and operating under similaz conditions without impacting the wetlands. Water from the wetland will overflow directly into the White River, which is immediately north of the wetland, as shown on Map C-2. A Gravel Well Permit will be applied for with the Colorado Division of Water Resources. No augmentation Plan is needed since this area has under appropriated water available. The mining of the deposit will occur to the limits shown on Exhibit C-2, Mine Plan Map with slopes no steeper than 2H:1 V around the perimeter of the pit. The interior slopes however, may be mined using a O.SH:1 V to neaz vertical slope on active mining faces. Highwall mining will progress Yo an offset of the crest line which marks the mid-slope of the final mining 2H:1 V slope. Both boundaries will be staked prior to mining in the azea. This offset serves two purposes. First, the volume of material left in the highwall will allow the crest to be pushed towards the toe with the final mining slope of 2H:1 V, which will maximize gravel recovery and additionally will reduce the required backfill material to bring the slopes to a 3H:1 V slope. Secondly, this offset provides additional slope stability. This is demonstrated through no evidence of slope failure during the life of the pits which have used similar techniques in the same general area. However, a failure would be governed by the internal angle of friction of the material. This would limit the failed slope to an angle of 38 degrees or ~1.3H:1 V. This failure would not only stay within the permit azea, it would stay within the final slope envelope. The 2H:1 V slope at the perimeter will later be backfilled to a maximum slope of 3H:1 V, as shown on Map F. YVhite River City Pit, April 07 D-3