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seepage volume reported in "Pre-Feasibility Study Report— Dawson Filtered Tailings Storage <br /> Facility" (Amec Foster Wheeler, 2016). The estimated seepage quality thus derived was then <br /> compared to the groundwater quality standard and the baseline groundwater quality to <br /> ascertain its suitability for discharge. <br /> In deriving the seepage quality estimate, a number of assumptions were made: <br /> • All infiltration water contacting the tailings will acquire the quality of filtrate <br /> • Leaching of development rock in the FTSF will occur at a 1:1 water to solid ratio <br /> • The metal release in the SFE tests represent an ongoing release rate as opposed to total <br /> soluble metal available <br /> • No elements precipitate out of solution <br /> • The ratio of tailings volume to development rock volume is the same as the ratio of <br /> tailings footprint area to buttress footprint area. <br /> The FTSF is expected to contain 500,000 short tons of tailings and 4,200 short tons of <br /> development rock. Tailings filtrate quality will dominate the FTSF seepage quality. The <br /> predicted seepage quality meets the groundwater quality standard, with the exception for <br /> manganese. However,the predicted manganese concentration (0.071 mg/L) is less than the <br /> background groundwater concentration (0.14 mg/L). The groundwater quality standard is 0.05 <br /> mg/L. <br /> The predicted seepage quality presented herein would be reflective of short term and operating <br /> conditions. The seepage quality estimates for the long term will be developed once the kinetic <br /> tests on tailings are complete. <br /> Test data and a detailed discussion of the geochemical characterization of the FTSF is provided <br /> in Appendix B. <br /> 2.7.4 Monitoring Well Network <br /> The following monitoring program, including the QAPP in Appendix M,will be implemented to obtain <br /> groundwater quality and water level data for both baseline and during mill/mine operations. Water <br /> quality monitoring will occur quarterly and water level data will occur monthly throughout the life of the <br /> mine. Analytical results will be compared to the most restrictive groundwater standard in WQCD <br /> Regulation No. 41 provided in Tables 2.7.4-1 and 2.7.4-2. <br /> An existing monitoring plan has been implemented at the property including two monitoring wells and <br /> two surface monitoring locations. The monitoring plan includes the collection of water levels in the <br /> existing wells, observation of surface flow conditions and the collection of water quality samples from <br /> both the surface and ground water systems. The existing monitoring plan monitors both of the surface <br /> drainages that cross the property and both of the aquifers identified beneath the property. The <br /> monitoring of these locations will be performed on a quarterly basis. The locations of the monitoring <br /> points have also been shown in Figure 1 (Permit Nos. 296711 and 296712). An additional proposed <br /> future downgradient monitoring well is planned for construction to allow for additional monitoring of <br /> water level changes in the aquifers. <br /> A new monitoring well network has been proposed with wells located as presented in Figure 3. The <br /> newly proposed monitoring well network, as presented, includes: <br /> 41 <br />