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2.0 OPERATIONAL WATER BALANCE <br />2.1 DEPLETIONS <br />2.1.1 Evaaorative Losses <br />The gross surface water evaporation calculation is based on a free water surface <br />evaporation of 39 inches year' (Farnsworth and Peck 1982). The lengths of <br />dewatering trenches for each year of operations are: <br />Table 2. Linear feet of trench <br />Year of Mining Operation Linear Feet of <br />Trench <br />Year 1 7418.6 <br />Year 2 7418.6 <br />Year 3 5920.9 <br />Year 4 3150.4 <br />The width of the trenches will average 4 ft. Settling ponds will total 1.7 ac of <br />open water. The open water surface area due to dewatering trenches and <br />sediment pond will be 2.38 ac, 2.38 ac 2.24 ac and 2.01 ac for each of the 4 <br />years respectively. The predicted total annual evaporation has been calculated to <br />be 5.81 acre-ft year', 5.81 acre-ft year', 5.48 acre-ft year' and 4.89 acre-ft year' <br />for each of the four years respectively. The monthly evaporation worksheet <br />calculation of total annual evaporation by month is given in Appendix AI.1 <br />2.1.2 Mined Losses and Dust Control Losses <br />Water lost due to pore water extracted with the mined product has been <br />calculated to be 15.92 acre-ft year'. The calculation is based on gravel that is <br />4% water by weight. The calculation of total annual mined loss by month is given <br />in Appendix AI.2. <br />The total annual consumptive use for dust control will be 1.2 acre-ft. The monthly <br />distribution of water that will be used for dust control is given in Appendices AI.2. <br />2.2 NET WATER DEPLETION <br />The net water loss per year can be written as: <br />(E Monthly Gross Evaporation) + (E Monthly Volume of Water Extracted With <br />Mined Product) + (E Monthly Volume of Water Used for Dust Control). The net <br />annual water loss or potential injury to Boulder Creek is given in Appendix AI.3. <br />2.4 REPLACEMENT <br />Asphalt Specialties Co, Inc. is in the process of negotiating a lease agreement <br />with the City of Louisville for replacement water. Bob Carlson, the District 6 <br />