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<br />Mr. Andy Rodriguez, P.E. <br />December 2, 2008 <br />Page 2 <br />Depletions <br />Currently 0.56 acres of ground water surface is exposed in dewatering trenches at the <br />Parker-Dersham Mine (WDID 0203026). Consumptive use from the operation of this site <br />consists of 8.83 acre-feet of water lost in product (4% moisture of 300,000 tons of raw <br />material), 1.67 acre-feet for on-site dust control and 1.66 acre-feet of evaporation from the 0.56 <br />acres of exposed lake surface. The total consumption at this site from mining operations is <br />12.15 acre-feet. <br />The depletions from the mining operation were lagged to the stream using the SDF <br />method. The construction of the slurry wall at the Baseline Resource site affects the timing of <br />the lagged impacts on the South Platte River. The applicant previously prepared a numeric <br />model to account for this affect. According to the model, the SDF for the Batch Plant <br />production well (concrete production and dust suppression) was estimated to be 176 days and <br />the SDF for the evaporation loss and water lost in product was estimated to be 205 days. <br />Replacements <br />The proposed source of replacement for this pit is nontributary ground water pumped <br />from an existing Laramie-Fox Hills aquifer well. <br />The nontributary Laramie-Fox Hills aquifer water will be withdrawn by an existing well <br />pursuant to permit no. 64750-F. Additional information regarding the well is shown below: <br />Well Field WDID None <br />Well Field Name None <br />Relevant Water Right Case Number None <br />Well WDID 0210166 <br />Well Name Hall Irwin LFH 64750-F <br />Relevant Well Permit 64750-F <br />Well Location NE NESE %, SEC 36, T1 N, R67W, 6TH PM <br />Aquifer Laramie-Fox Hills <br />Allowable AF Amount 43.5 AF <br />Maximum Pumping Rate 100 pm <br />The well is currently permitted for industrial, commercial and augmentation use. The <br />Applicant's accounting includes the 2% relinquishment requirement for the nontributary <br />Laramie-Fox Hills water. <br />In addition to replacing depletions resulting from this mining operation, 21.27 acre-feet <br />will be pumped from the Laramie-Fox Hills well to replace depletions resulting from operations <br />at the Baseline Resource site in accordance with the C.R.S. 37-90-137(11) SWSP approved for <br />Hall-Irwin. Since the Laramie-Fox Hills water is being used as a replacement source for both <br />plans, the applicant's accounting for each SWSP must specify the total amount of Laramie-Fox <br />Hills water released and the amount associated with each SWSP.