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Mr. Andrew Rodriguez September 11, 2007 Page 2 You have provided a monthly breakdown of the annual depletions at this site. Annually, these are made up of 14.2 acre-feet of evaporative loss from 4.8 acres of water surface exposed after December 31,1980, 14.7 acre-feet of water lost with 500,000 tons mined product, 15.5 acre-feet consumed by batching 150,000 cubic-yards of concrete and 1.9 acre-feet used for dust suppression. Water for dust suppression and concrete batching will be pumped from the settling ponds on the site. In the event that the settling ponds are not available for operational use an existing well, permit no. 62972-F, will be used for dust suppression and concrete batching. Should the well be used the monthly volumes pumped will not exceed the monthly volumes specified in attached Table 2. Depletions resulting from mining operations were lagged to the stream system using the Glover method, a distance from the well to the stream of 2,750 feet for evaporation losses and 3,000 feet for operational losses, aquifer iransmissivity of 140,000 gallons per day per foot, specific yield of 0.2 and no flow boundary of 10,000 feet. Replacements The proposed source of replacement water for this pit is 54.63 acre-feet of fully consumable effluent leased from the City of Broomfield. The Broomfield water wilt be released from the their wastewater treatment plant, which is located approximately 29.75 mile upstream of the operation. Of the 54.63 acre-feet of lease water from the City of Broomfield, approximately 15°I° will be lost during transft, based on 0.5% per mile for the 29.75 miles from the Broomfield wastewater treatment plant to the Heit Sand and Gravel Mine. The amount of City of Broomfield replacement water that reaches the Heit Sand and Gravel Mine is 46.3 acre-feet. The monthly depletions and replacement requirements are found on the attached Table 1. Conditions of Approval I hereby approve the proposed substitute water supply plan in accordance with §37-90- 137(11), C.R.S., subject to the following conditions: 1. This plan approval shall be valid between September 1, 2007 through August 31, 2008 (period of effluent lease with the City of Broomfield), unless, otherwise revoked or modified. If this plan will not be made absolute by a water court action by the plan's expiration date, a renewal request must be submitted to this office with the statutory fee (currently $257) by July 1, 2008. 2. The losses associated with this mining operation must not exceed a total of 46.3 acre-feet for the duration of this permit approval. These losses include 14.2 acre- feet of evaporation from the proposed exposure of 4.8 acres of groundwater, 14.7 acre-feet of water lost in 500,000 tons of mined aggregate, 15.5 acre-feet consumed in batching of 150,000 cubic yards of concrete and 1.9 acre-feet used for dust suppression. Should the annual losses at the site exceed 46.2 acre-feet prior to the expiration of this plan, an amendment will need to be filed. 3. Approval of this plan is for the purposes as stated herein. Any additional uses of this water must first be approved by this office.