2017-02-28_REPORT - C1981020 (2)

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2016 AHR McClane & Munger Canyon Mines Page 6 Probable Hydrologic Consequences As discussed above, and as documented in past annual hydrologic reports, the mines had and will have a negligible effect upon the hydrologic regime of East Salt Creek. The area disturbed is small, sedimentation and surface water systems have functioned well for over ten years. The inherent poor quality of surface water in the area is the result of site specific environmental factors not from any impact caused by the mines. Most but not all of the storm events that have exceeded the design criteria required by the DRMS have not been a problem for the system to handle. The effect that the mine has on the groundwater hydrology of East Salt Creek has not been detected. The mines will not have a detrimental impact upon the groundwater of the East Salt Creek valley. This is based partially on the relative sizes of the operation and the size of the aquifer. It is also based on the fact that the groundwater contained in the alluvium is substandard. East Salt Creek is an accurate name. The water contained in the alluvium is virtually unusable. Field water sampling has shown that the conductivity of the groundwater is extremely high (3,000 to 100,000). Data gathered for SW -1 and GW -3 are presented in the Tables N-1 through N-7 in Appendix N. The Division's 1987 Material Damage guidelines require any measured salinity values over 1,000 umhos/cm be reported as `suspect' values. Since baseline values for SW -1 and GW -3 far exceed the Division's 'suspect' levels, the Operator compiled data in order to demonstrate mine discharge does not add salinity to the already high values, rather, lowers the salinity in SW -1 and GW -3 during the irrigation season. By improving the salinity of the waters in East Salt Creek and the East Salt Creek alluvium, downstream farmers will not suffer loss of production due to the addition of mine discharge.