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2004 AHR McClane & Munger Canyon Mines Pa e 5 Groundwater Table 5 shows the results of groundwater sampling during 2004. The average static water level for the baseline years of 1981 and 1986 is also shown. Results of quality sampling are consistent with the results from previous years. Water depths were lower than baseline values. GW-4 in close proximity to a hay field that is irrigated during dry periods and in danger of being eroded with an oxbow has been replaced with GW-3. GW-3 is located adjacent to the road south of GW-4 and should be outside of the influence of the irrigation of the hay field. Refer to Figure 4.2-2 of the McClane Canyon Permit. The Division of Minerals & Geology has approved this substitution. Pond Discharges There was one discharge from the McClane sediment pond during the year. The sediment fences at McClane, Munger Canyon and Loma were maintained as necessary. The Munger Canyon gob disposal area sediment pond was constructed during the reporting period. Discharge monitoring from the sediment ponds and mines are regulated by the Colorado Discharge Permit System Numbers CO-0038342 (McClane) and CO-0040827 (Munger). Copies of Quarterly Discharge Monitoring Reports have been provided, under separate cover, to the DMG at the same schedule required by the CDPS Permit. They are included in this report by reference. McClane Creek Temporary Diversion The Operator placed four wooden gabions in the McClane Creek channel during 1997 to ensure the channel would remain stable. The gabions were to provide a solid place in the channel bottom to limit any further erosion. Please see the discussion in Volume II, Appendix M, beginning on page M-5. During December 2004, the Operator surveyed the channel to determine if the gabions were functioning as designed. The survey was compared to the channel profile shown on page M-6. Only three of four gabions were located and they did not align very well with the data shown on page M-6. Also, the elevation datum has changed from that used in the survey in 1997. The channel profiles were compared as shown of Figure 5. The best fit was found by aligning the upper most gabions from both surveys. There is some erosion evident below the upper gabion that should be jointly inspected by the Operator and the DMG. Probable Hydrologic Consequences The mines will have 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 storm events that have exceeded the design criteria required by the Division of Minerals & Geology 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.