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Timnath-Connell Substitute Water Supply Plan Page 2 of 7 <br />March 31, 2017 <br /> <br />Northern Colorado Water Conservancy District’s Loveland (2006-2015) and East Fort Collins (1994- <br />2015) weather stations]. Net evaporative depletions are 20.82 acre-feet per year for the 8.10-acre <br />recharge pond and 15.50 acre-feet per year for the remaining 6.03 acres of exposed ground water <br />(see attached Tables 1 and 2). The evaporative loss from the recharge pond is deducted from the <br />deliveries to the recharge pond in the given month prior to determining the net positive accretion <br />or depletion from the pond and is thus not included in the total net depletions covered in this <br />SWSP. <br />It is anticipated that 0.8 acre-feet of water will be used for on-site dust control during this <br />plan period, based on an estimate of 5 truckloads of 4,000 gallons of water per month. Water used <br />for dust control purposes is assumed to be 100% consumed. <br />The Timnath-Connell Pit will not be mined for sand and gravel during this approval period, <br />therefore there will be no water lost in mined product. <br />The total annual consumptive use from evaporation (excluding the recharge pond) and <br />operational uses at the site is 16.30 acre-feet (see attached Table 4). The Alluvial Water <br />Accounting System (AWAS) stream depletion model developed by the Integrated Decision Support <br />Group was used to determine the lagged depletions from the Timnath-Connell Pit to the Cache La <br />Poudre River from past and projected evaporation and operational losses at the site. The following <br />parameters were used in the model: <br />• Distance from the centroid of the 6.03 acres to the river (X) = 2,218 ft <br />• Alluvial aquifer width (W) = 5,300 ft <br />• Specific yield (S) = 0.2 <br />• Transmissivity (T) = 50,000 (gpd/ft) <br />Lagged stream depletions are estimated to total 16.13 acre-feet during this plan period, as shown <br />on the attached Table 4. <br /> The Applicant has continuously dewatered the Timnath-Connell Pit since 1999. Water <br />pumped for dewatering is discharged into the adjacent recharge pond. This diversion into the pond <br />is not a part of the metered Box Elder Ditch Shares that are also discharged into the recharge pond. <br />The dewatering depletions are lagged to the river using the same parameters as the other lagged <br />depletions from the Timnath-Connell Pit as described above. The dewatering accretions are lagged <br />to the river using the same parameters as the site depletions with the exception of using a distance <br />(X) from the centroid of the recharge pond to the river of 3,500 ft. This dewatering operation <br />creates lagged accretions that mimic the lagged depletions. Thus at the cessation of dewatering <br />the only depletion that would impact the river is that which is attributable to the “first fill” of the <br />pit. The Applicant intends to line the pit when mining activity is complete thereby eliminating the <br />depletion caused by the “first fill”. Should dewatering operations cease prior to the pit obtaining a <br />liner approval from the Division Engineer, the Applicant must address the lagged depletions due to <br />the “first fill.” <br />Replacements <br /> Connell Resources, Inc. owns a total of 4.0 Box Elder Ditch Company (“BEDC”) (WDID <br />0300926) shares that were part of 64 shares historically used to irrigate the property known as the <br />John Weitzel Farm, which is the site of the Timnath-Connell Pit. The primary source of replacement <br />water for this SWSP will be from recharge of 2.5 of these BEDC shares. The shares will be diverted <br />into a recharge pit (WDID 0302059) located on the Timnath-Connell site. The recharge pit was <br />constructed in an area of the mining site that was previously excavated for sand and gravel mining.