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Table 9 Mining Groundwater Level Table Location Exist WL. Mt Diff. M2 Diff. M3 DiH. M4 Diff. MS Diff. M6 Diff. WCR 4 &WCR 27 4932.8 4932.8 0.0 4932.8 0.0 4932.8 0.0 4932.8 0.0 4932.6 0.2 4932.1 0.6 WCR 4 & HWY 85 4930.3 4930.3 0.0 4930.3 0.0 4930.3 0.0 4930.3 0.0 4930.2 0.1 4930.0 0.3 WCR 6 &WCR 27 4927.8 4927.4 0.3 4927.2 0.6 4927.6 0.2 4926.5 1.3 4925.7 2.1 4921.0 6.7 WCR 6.25 &WCR 27 4925.7 4925.2 0.6 4924.7 1.0 4925.3 0.4 4923.5 2.2 4922.1 3.6 4916.5 9.2 WCR 6.25 & HWY 85 4925.5 4924.4 1.1 4924.2 1.3 4923.6 1.8 4923.7 1.8 4922.9 2.6 4917.0 8.5 WCR 8 & RR 4918.5 4914.8 3.6 4912.1 6.4 4901.5 17.0 4911.8 6.7 4916.3 2.2 4917.1 1.4 WCR 8 6 HWY 85 4915.2 4913.8 1.4 4911.4 3.8 4907.1 8.1 4907.8 7 d 4913.4 1.8 4914.2 0.9 Sakata Irr. Well 4911.6 4899.8 11.8 4899.9 11.7 4905.3 6.3 4909.9 1.7 4910.9 0.7 4911.1 0.6 WCR 10 &WCR 27 4909.2 4903.2 6.0 4906.2 3.0 4907.0 2.2 4909.2 0.0 4909.5 0.0 4909.6 0.0 WCR 10 & HWY 85 4905.9 4902.7 3.2 4905.2 0.7 4905.5 0.4 4905.9 0.0 4906.0 0.0 4906.0 0.0 WCR 10.5 &WCR 27 4906.4 4905.7 0.7 4906.4 0.0 4906.4 0.0 4906.4 0.0 4907.9 0.0 4908.1 0.0 Notes: -Approximate location of water level -Existing WL is the water level after calibration. - M1-M6 indicates water level at location after the particular mining phases have begun. -Diff. is difference in modeled existing condition and modeled mining water level. As seen in Table 9 the areas closer to the mine will be affected more severely and as the dewatering process moves further from theses wells the fluctuations in the groundwater levels will decrease. i 4.2.1 Mit gation Mitigation measures are proposed to reduce the extent of groundwater drawdown due to mining. Measures that are recommended to help alleviate the effects of mining include: 1) limiting the size of each mining phase, 2) pumping dewatering water to a recharge pond or injecting dewatering water into irrigation wells on the injured sites or close to the injured sites, 3) supplementing the injured imgation wells with Fulton Ditch shares for a period a time, and 4) building cisterns on sites with injured domestic wells, and 5) drilling wells deeper. Recharging the aquifer has been discussed and two of the major farmers (Sakata Farms, Villano Brothers Farms) in the area have agreed to using either a recharge pond/infiltration gallery or an injection well. A recharge pond will be excavated onsite and dewatering water that has been tested for total suspended solids (TSS) and pH will be delivered to the pond which will then pemolate down into the aquifer. Refer to Figure 10 for a schematic of a proposed recharge pond. The aquifer is conducive to recharge ponds because the groundwater table is approximately 20 feet below existing ground and the ponds can be constructed to hold a sufficient volume of water, Injection wells will be used in the same fashion as the recharge wells as seen in Figure 11. Modeling was performed with four recharge (500 gpm) sites for mining and Figure 11a shows the approximate location of the recharge sites and the area of influence with the use of recharge sites and without the use of recharge sites. As presented in Figure 11a the use of recharge sites reduces the influence on the groundwater table surrounding the Site. 4.3 Post-Construction IReclamationl Simulation The proposed Site reclamation after mining consists of surrounding each of the mined areas with aloes-permeability compacted clay liner (CCL) derived from the claystone bedrock for the purposes of creating a water storage vessel. Figure 12 shows the proposed alignment for the Site final reclamation. The claystone will be processed in place and compacted at a 4:1 (horizontal to vertical) upstream slope. The CCL will act as a hydraulic barrier between the water inside the storage vessel and the natural groundwater table. This model was used to evaluate the long-term effects on the groundwater regime of the post construction project. Groundwater Model Report - SW TKO Water Storage Project - 9 - February 2005