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Ground Water Quality Summary. Increasing TDS trends were observed at <br />nine wells downgradient of mining. Nine downgradient wells exhibit <br />stable or decreasing TDS trends. One well did not have enough water to <br />sample this year. TDS values this year were below PHC predicted values <br />for all wells except for WHAL7-2, WOV14, WOV17 and WW14. <br />Agricultural ground water standards were exceeded this year at certain <br />monitoring wells. Tab 7 of the Seneca II-W PAP contains a section that <br />discusses the suitability of using water from the various aquifers <br />monitored at the Seneca II-W Mine for irrigation or livestock watering. <br />The discussion mentions that all aquifers prior to mining at the Seneca <br />II-W Mine have exhibited several parameter concentrations in excess of <br />both irrigation and livestock standards compared, rendering them <br />questionable regarding their suitability for either irrigation or <br />livestock. All bedrock aquifers affected by mining have been determined <br />to have transmissivities less than 100 ft2/day, which would also <br />preclude their use for yielding sufficient water for irrigation, or even <br />livestock. <br />Surface Water <br />A summary of surface water monitoring sites and sampling history is <br />presented in Table 7. At Seneca II-W, all stream sites (unless otherwise <br />noted) are monitored for flow and field parameters (flow, temperature, <br />pH, and electrical conductivity) and the surface water parameter list, <br />Table 8, during April, June, and September. NPDES Discharge Point 017 is <br />monitored weekly (when accessible by truck) for flow and pH. All five <br />NPDES sites are monitored monthly for NPDES parameters and field <br />parameters. Springs are monitored annually (April-June) for flow, field <br />parameters, and, if flow exceeds five gpm (0.011 cfs), the surface water <br />parameter list. Monitoring frequencies for surface water sites may be <br />found in Appendix 15-3a of the Seneca II-W PAP. <br />All surface water data is found in Appendix E. Data for each site begins <br />with a flow hydrograph of all historic data (plus an annual hydrograph <br />for NPDES sites), followed by a listing of individual water quality and