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<br />70,000 tons of material will be mined and washed from the azea annually. At 4°!o moisture <br />content by weight, the depletion wou]d tota12.1 acre-feet per year (Table 2). <br />Water will also be applied to haul roads and stockpiles for dust control from a 2,000 gallon <br />capacity water truck three days a week during the year. This results in a consumptive use of I.0 <br />acre-feet per year (Table 2). <br />Total operational consumptive uses for the Loveland Pit aze 3.1 acre-feet (Table 2). <br />The total calculated stream depletions due to the mining operations and evaporation at the <br />Loveland Pit are 4.0 acre-feet for the year (Table 2). <br />MINING STREAM DEPLETIONS <br />Due to the fact that the site is set back from the river, the evaporative depletions were assumed <br />not to be instantaneous. A stream depletion model was completed for the Loveland Pit to display <br />the lagged effect of the depletions (Appendix A). A summary of the monthly stream depletions <br />due to the mining operation can be found in Table 3. <br />The stream depletion model for the mining operation was developed under the following <br />assumptions: <br />The estimated distance from the active stream was 450 feet. The location represents the <br />down-gradient extent of the exposed surfaces as defined by the mining limits. <br />• The transmissivity was assumed as 50,000 gaUff/day. There was no transmissivity data <br />available for this area. A value of 50,000 gaUday/ft was chosen based on average <br />transmissivity data for South Platte River tributaries similaz to the Big Thompson River such <br />as the St. Vrain River and Boulder Creek. <br />• The specific yield was assumed to be 0.2, which is typical for an alluvial aquifer. <br />• The location of the parallel impermeable boundary was assumed to be a distance of 4000 feet <br />from a live stream. Source: USGS Depth to the Water Table in the Boulder-Fort Collins- <br />Greeley Area, Front Range Urban Corridor, Colorado. <br />REPLACEMENT WATER <br />A lease of 5.0 acre-feet of fully consumable water from the City of Loveland will provide <br />replacements for the mining operation all year. The lease has a duration of three yeazs. A letter <br />describing this lease is included in Appendix B. The lease is currently at the City of Loveland for <br />-Page 3 <br />