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Mr. David M. Heintz Page 4 of 8 MMM South Platte Combined Replacement Plan January 8, 2015 TABLE D - TRANSIT LOSS PER SITE Point of Distance From Transit Loss From Projected Pit Depletions Replacement Replacement Source Replacement Source (acre Feet) (miles) (%) Howe Pit 8 4% 0.50 Riverbend West 25 11.5% 26.37 Riverbend East 21 11% 154.28 For the purpose of this SWSP the proposed transit loss is accepted however, the transit loss is subject to change if the division engineer or the water commissioner determines that a different transit loss needs to be assessed to the Aurora leased water. The total lagged mining depletions and replacements are shown on attached Table 5. Dewatering Dewatering will continue to occur at the Riverbend East Pit during the period of this SWSP. Based on mining projection for the term of this SWSP, MMM anticipates dewatering the actively mined area of the Riverbend East site at an estimated rate of 5,000 gpm, or approximately 674 acre- feet per month. The dewatering operation can pump directly to the river producing an instant credit and a lagged depletion, or can pump to the north recharge pond producing a lagged credit and a lagged depletion. Dewatering credits will be factored into the monthly accounting to determine net effect to the South Platte River. Dewatering depletions will be lagged back to the river using the same parameters as shown in Table C for Riverbend East. A portion of the dewatering water from the Riverbend East site will be pumped directly to a recharge pond located on the Riverbend East property. The location of the recharge pond is shown on the attached Figure 2. The recharge pond accretion credits will be calculated using the Glover analysis using the following aquifer parameters: the distance to the river (X) = 800 feet, the aquifer width (W) = 6,750 feet, transmissivity (T) = 80,000 gpd/ft, and specific yield (5) = 01 An example of the dewatering operations is shown in Table 4 which assumes that 5,000 gpm is continuously pumped from the Riverbend East site during the period of this SWSP. Based upon recent dewatering operations at the Riverbend East site Table 4 assumes that 16 percent of total dewatering water is pumped to the recharge ponds and the remaining 84 percent is pumped back to the South Platte River. The total volume of recharge credits in Table 4 is used as a credit against depletions in this combined plan. Totalizing flow meters are installed at each discharge location and meter readings must continue to be reported on the submitted accounting with actual credits/depletions determined in real time. Long Term Augmentation In accordance with the letter dated April 30, 2010 from the Colorado Division of Reclamation, Mining, and Safety ("DRMS"), all sand and gravel mining operators must comply with the requirements of the Colorado Reclamation Act and the Mineral Rules and Regulations for the protection of water resources. The April 30, 2010 letter from DRMS requires that you provide information to DRMS to demonstrate you can replace long term injurious stream depletions that result from mining related exposure of ground water. For Howe Pit and Riverbend East, Denver Water is the DRMS permit holder. As municipal entities are not required to post bonds, these sites are not required to be bonded to cover the cost of lining or backfilling the site. For Riverbend West,