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