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Using the climate data described above, at an elevation of 5,700 feet, a latitude of 38 degrees <br />17 minutes, and starting and ending dates computed when the average temperature reached <br />45 degrees, the results show a crop CU demand of 2.05 acre -feet per acre. The inputs and results <br />are shown in Table 6. <br />Analysis of the diversion records for the use of both the 27 and 34 shares indicates that they have <br />not produced a full water supply for the crop in most months (i.e., water -short system). <br />Therefore, the CU must be calculated by determining how much water arrives at the crop for <br />each share and applying an irrigation efficiency. The comparative values are shown in <br />columns 3 and 6 of Table 7. <br />The first portion of Table 7 shows the CU analysis for 74 acres irrigated by 27 shares. The <br />monthly field delivery to the crop is calculated by subtracting a 15% transit loss from the <br />monthly averages shown in Table 3. The resulting amount is 235.74 acre -feet. Because the <br />water is used and reused several times in a ditch system such as the CC Ditch, an efficiency <br />coefficient of 45% is reasonable. The 45% coefficient is often used as a standard by the DWR in <br />this region. The resulting CU for 27 shares and 74 acres is 106.08 acre -feet that can be changed <br />and fully consumed. The other 55 %, 129.66 acre -feet, will be released to replace historical <br />irrigation return flows. WFC has elected to limit the CU amount for 27 shares to a maximum of <br />97.8 acre -feet as defined in case 88CW55. These amounts are shown in Table 7. <br />Case No. 88CW55 changed the water rights for 27 shares to include industrial uses, set aside <br />97.8 acre -feet that could be used for industrial purposes, and designated the rest to be released <br />back to the stream to compensate for historical return flows. The 1988 Report stated that "[I]n <br />order to account for `losses' due to timing of flows and diversions, and measurement error, an <br />administrative loss factor of 0.5 is used." The 0.5 factor in the 1988 Report was proposed to <br />compensate surface water rights for "timing delays, delivery losses, and any variation in assumed <br />conditions" of pit inflow. <br />The administrative loss factor conservatively included in the 1988 Report need not be used in the <br />current augmentation plan. Groundwater modeling tools and technology were not widely used <br />and available when the 1988 Report was prepared. With current technology, the timing of these <br />impacts can be calculated. The Glover method can calculate the delayed impacts to the stream <br />from well pumping, both from the domestic supply wells and dewatering from the mine area. <br />These analyses compensate for flow variation by using averages established from historical use. <br />Descriptions of these methods are included in the 2013 BBA Report, referenced later in this <br />report. The mine can also measure diversion amounts with flow meters and truck volume <br />records. The delivery amount of replacement water can be accurately measured with Parshall <br />flumes by the CC Ditch rider whenever necessary. There is no longer a need for the use of the <br />conservative 0.5 compensation factor to make sure that depletions are replaced in time and <br />amount to prevent injury, and the terms and conditions described below accomplish that purpose. <br />The second portion of Table 7 shows the CU analysis for the other 34 shares that irrigated <br />67.18 acres. Using the same method described above, the resulting CU for the 34 shares and <br />67.18 acres is 123.82 acre -feet that can be changed and fully consumed and 173.04 acre -feet that <br />4 <br />