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2009 AHR McClane & Munger Canyon Mines Page 5 <br />McClane Creek Temporary Diversion <br />The Operator placed four wooden gabions in the McClane Creek channel during 1997 to <br />ensure the channel would remain stable. The gabions were to provide a solid place in <br />the channel bottom to limit any further erosion. In 2004 a re-survey was conducted and <br />the data and inspection observations show there has been significant erosion <br />subsequent to the 1997 gabion installation. Future high flow events may result in <br />additional channel scour and side-cutting erosion. Portions of the diverted channel <br />appeared to be unstable and further erosion may be likely. To alleviate this problem, the <br />operator installed a 48" culvert ("P") under the haul road during 2006 in order to <br />reconnect upper McClane Creek to it's original lower segment. <br />Probable Hydrologic Consequences <br />As demonstrated above, the mines had and will have a negligible effect upon the <br />hydrologic regime of East Salt Creek. The area disturbed is small, sedimentation and <br />surface water systems have functioned well for over ten years. The inherent poor quality <br />of surface water in the area is the result of site specific environmental factors not from <br />any impact caused by the mines. <br />Most storm events that have exceeded the design criteria required by the Division of <br />Reclamation, Mining and Safety have not been a problem for the system to handle. The <br />effect that the mine has on the groundwater hydrology of East Salt Creek has not been <br />detected. <br />The mines will not have a detrimental impact upon the groundwater of the East Salt <br />Creek Valley. This is based partially on the relative sizes of the operation and the size of <br />the aquifer. It is also based on the fact that the groundwater contained in the alluvium is <br />substandard. East Salt Creek is an accurate name. The water contained in the alluvium <br />is virtually unusable. Field water sampling has shown that the conductivity of the <br />groundwater is extremely high (3,000 to 100,000). <br />Data gathered for SW-1 and GW-3 are presented in the Tables N-1 through N-7 in <br />Appendix N. The Division's 1987 Material Damage guidelines require any measured <br />salinity values over 1,000 umhos/cm be reported as 'suspect' values. Since baseline <br />values for SWA and GW-3 far exceed the Division's 'suspect' levels, the Operator <br />compiled data in order to demonstrate mine discharge does not add salinity to the <br />already high values, rather, lowers the salinity in SW-1 and GW-3 during the irrigation <br />season. By improving the salinity of the waters in East Salt Creek and the East Salt <br />Creek alluvium, downstream farmers will not suffer loss of production due to the addition <br />of mine discharge.