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Dan_Ma_fl_iews 3 June 8.2 <br />CAM - See Table 4.2 showing nomenclature clarification for drill holes included in current monitoring <br />plan. To eliminate the confusion between the alluvial wells and the ground water monitoring wells, a <br />paragraph was added to the Groundwater Quality Monitoring Program shown on page 4-17 and a <br />double asterisk was added to Table 4.2-1 thru 4.2-5 stating the AW do not equal GW monitoring wells. <br />No update to Figure 4.2-2 was required. There is not enough data to develop a groundwater contour <br />map for the East Salt Creek Alluvium. Atypical well completion log is presented in Figure 4,1-7, and <br />includes surtace elevation, type of casing, diameter of casing, total depth of well, perforated interval <br />and formation completed in for the GW wells except there is no perforated interval for GW-1. <br />4. DMG - On page 5 of the AHR it is stated that the effect that the mine has on the groundwater <br />hydrology of East Salt Creek has not been detected. Yet data from G W-3 as indicated by Table 5 of <br />the AHR shows Heady a threefold increase in conductivity from the baseline year average to the 2005 <br />year average. There also appears to be a significant drop in the water level measured at this well. It is <br />further indicated on page 5 that G W-3 is located outside of the influence of the irrigation of the hay <br />field that affected Well GW-4. Given this information, it is unclear what might explain the conductivity <br />increase, and whether there may 6e some mine related effect on the East Salt Creek Alluvium. <br />Further explanation and discussion is warranted in this case under Probable Hydrologic <br />Consequences section of the AHR. <br />CAM -Added section addressing mine impact on East Salt Creek Alluvium in PHC section of 2005 AHR, <br />see updated AHR page 6. See Table 4.2i for the baseline data for GW monitoring wells. Updated Table <br />5 to show the baseline data for GW-1 and GW-3. <br />5. DMG -There appears to 6e a discrepancy with reference to the baseline data for GW-3 on Table 5 of <br />the AHR (AW-6 = GW-3). Comparison of Figure 4.1-2 with Figure 4.2-2 of the McClane permd and cross- <br />referencing this to Table 2.5-1 of the Munger permit appears to show that MW-2 = GW-3. It is unclear if <br />MW-2 equates to AW-6. Please check the reference to baseline data for GW-3 on Table 5 of the <br />AHR, and update Table 5 if appropriate. Both permits need to be amended as necessary to ensure <br />that the relationship of AW, MW, and GW well designations is clear, consistent, and correct. <br />CAM -See Table 4.2 showing nomenclature correlation for drill holes in the current approved monitoring <br />program. To eliminate the confusion between the alluvial wells and the ground water monitoring wells a <br />paragraph was added to the Groundwater Quality Monitoring Program shown on page 4-17 and a double <br />asterisk was added to Table 4.2-1 thru 4.2-5 stating the AW do not equal GW. Baseline data for GW <br />monitoring wells are shown in new Table 4.2i and 4.2ii. <br />6. DMG -The McClane permit document indicates that since the proposed mine is located above the <br />alluvial fills no direct disturbance of the alluvial aquifer will result from the actual mining operation. The <br />AHR indicates that the effect that the mine has on the groundwater hydrology has not been detected. <br />However, mine water is discharged to McClane Creek at outfall 002, which then discharges to East <br />Salt Creek. Because McClane Creek is ephemeral and East Salt Creek is either intermittent or <br />ephemeral, at least the potential exists that the mine discharge could 6e tributary and at some point <br />impact the East Salt Creek alluvium. This combined with the fact that there has been some question in <br />the past about possible irrigation return flows affecting the quality of data from wells located in the <br />vicinity of the mouth of Munger Canyon, may indicate that an additional monitoring well would be <br />useful. One additional well maybe warranted in the East Salt Creek alluvium just below <br />McClane Canyon outside of the influence of the irrigated hay field. This well located below the <br />McClane Canyon mine discharge will aid in identifying the effect if any the mine has on the <br />groundwater hydrology of the East Salt Creek alluvium. <br />CAM -Considering the fact the McClane Canyon Mine has discharged water to East Salt Creek and its <br />alluvium for over twenty years, the operator questions the value of a new ground water monitoring well. <br />Since the alluvium has been affected, data from a new ground water monitoring well would be of <br />questionable value. Additionally, based on TDS and EC, mine water is typically better quality than East <br />Salt Creek. <br />