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The material submitted by EFCI does not analyze the available data for trends in water quality. <br />Chemical analyses of roof and floor samples are described in section 2.04.6 of the PAP. The <br />following statement was made to summarize the findings: <br />"Moderately alkaline pH values will decrease the potential for dissolution of soluble metals <br />including iron, nickel and zinc and should result in no signicantpotential for adverse <br />hydrologic impacts. Sample pH values indicate no potential for development of acidic <br />conditions and only marginal potential for development of excessively alkaline conditions <br />in the hydrologic system" (page 2.04.6 -23) <br />To date it has not been possible to verify these predictions. <br />i) Please provide a detailed analysis of the impact of the Southfield Mine on groundwater <br />quality, allowing the identification of trends in the data (perhaps a selection of individual <br />water quality parameters could be plotted against time, for example: TDS, [Fel, [Mn), <br />[Se]...) <br />ii) Please include data collected from each groundwater monitoring point in the analysis, <br />including N'IWNW (which may be dry), in accordance with the approved water <br />monitoring plan described in Exhibit 25, and make a comparison to predictions made in <br />the PAP. <br />RESPONSE: <br />i) An analysis, prepared by Weaver Engineering Services, of water quality trending can be found in APPENDIX "A" <br />included with this submittal. <br />ii) Data will be included from each available monitoring point (MW -NW is dry at 353 ft bgs) and will be compared <br />to predictions made in the PAP and are included in APPENDIX "A" . <br />2) Surface Water <br />Three streams drain the mine Southfield Mine permit area. Newlin Creek is considered a perennial stream <br />from its headwaters to the point of diversion (upstream of the permit area), but the entire base flow is <br />diverted by the City of Florence, rendering it an ephemeral stream below this point. Magpie Creek and <br />Second Alkali Creek are both ephemeral streams. <br />a) Surface Water Monitoring <br />There are two parts of the approved water monitoring program that relate to surface water. The first is <br />sampling of streams for water quality and flow at five locations: upper and lower Magpie Creek; upper <br />and lower Newlin Creek; and Second Alkali Creek, near MW65. Sampling frequency is <br />semi - annual on Newlin Creek and opportunistic, whenever flows allow, on the other two streams. Prior <br />to 2004, sampling was reported on a quarterly basis. <br />EFCI provided stream flow data from 2000 through 2013 with the TR43 application. During this <br />period no flow was reported on either Magpie Creek or Second Alkali Creek, with one exception: in <br />the second quarter of 2004 flow in upper and lower Magpie Creek was reported as "minimal" (a <br />volumetric flow rate was not reported). Table 3 lists the flow data for Newlin Creek that is found in <br />the TR43 application. The TR43 data for all three creeks is in agreement with past AHRs. <br />The data shows that on the three occasions when larger flows were recorded (greater than 3 cfs), <br />there was essentially no difference between the upstream flow and the downstream flow. For <br />recorded flows less than 3 cfs, the reach between the two stations acted as a losing reach, as some of the <br />flow infiltrated into the creek bed. <br />15 <br />