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Andy Rodriguez <br />March 31, 2008 <br />Page 2 <br />A well permit has been obtained for the gravel pit, permit no. 65812-F. <br />Depletions <br />Currently 11.11 acres of ground water surface is exposed at the Bernhardt pit. <br />Consumptive use from the operation of this site consists of 11.77 acre-feet of water lost in <br />product (4% moisture of 400,000 tons of raw material), 3.31 acre-feet for on-site dust control, <br />12.28 acre-feet used in the production of 100,000 tons of concrete and 32.0 acre-feet of <br />evaporation from the 11.11 acres of lake surface exposed after December 31, 1980. The total <br />consumption at this site from mining operations is 59.36 acre-feet. <br />Dewatering at the site commenced in October 2003 at a rate of 750 gallons per minute. <br />In 2004 dewatering decreased to 350 gallons per minute. All water pumped in 2003 and 2004 <br />for dewatering purposes was pumped from trenches into an on site pond for recharge back to <br />the Big Thompson River. In September 2004, pumping of the dewatering water into the pond <br />ceased. All water pumped from the trenches since September 2004 has been pumped from <br />within the slurry wall and used for the purposes described in this plan. Based on the analysis <br />previously performed by the Applicant there are no depletions from past dewatering operations <br />that will accrue to the river during this plan period. <br />The depletions from evaporation, water lost in mined product and dust suppression were <br />lagged to the stream using a Glover analysis and assuming a distance to the stream of 1,015 feet, <br />distance to the impermeable boundary of 2,976 feet, transmissivity of 100,000 gal/day/ft and <br />specific yield of 0.2. The depletions from well no. 60729-F (concrete production) were also lagged <br />to the stream using a Glover analysis and assuming a distance to the stream of 1,510 feet, <br />distance to the impermeable boundary of 2,587 feet, transmissivity of 100,000 gpd/ft and specific <br />yield of 0.2. <br />Replacements <br />The proposed source of replacement for the Bernhardt pit is leased excess <br />augmentation credits (63.06 acre-feet) available under the Town of Milliken ("Milliken") <br />substitute water supply plan ("SWSP") approve pursuant to C.R.S. 37-92-308(4). The <br />consolidated Division 1 Water Court cases associated with the Milliken SWSP are 2002CW339 <br />and 2005CW59. The excess credits from Milliken accrue to the Big Thompson River in the <br />same location that the lagged depletions from the Bernhardt Pit impacts the river, therefore, no <br />river conveyance losses will be assessed. <br />The plan estimates that in the event that the operator were to cease mining and <br />dewatering at the site there would be 10.4 acres of exposed water surface located outside of <br />the slurry wall. To provide the security of a permanent, renewable source of replacement <br />water, 3.25 shares of Kern Reservoir (a.k.a Windsor Lake) are hereby dedicated to this plan <br />and made appurtenant to the tract of land where the gravel pit is located, until a permanent <br />augmentation plan for the gravel pit has been adjudicated or all consumptive use at the site has <br />ceased and all lagged depletions have been replaced. The depletions resulting from <br />evaporation off of the 10.4 acre pond are estimated to be 29.96 acre-feet. According to the <br />analysis provided for the Town of Windsor SWSP approved February 25, 2008, the 3.25 shares <br />of Kern Reservoir have a historical consumptive use of 30.8 acre-feet, therefore, the shares are <br />.. <br />