REP22811 - Laserfiche WebLink

Home Browse Search

DMG Concern Alluvial Wells Why does 008-AW-3 show a much higher EC reading than its upstream cousin 008- AU-3? Approximately 1 /3 to 112 miles separate these Fish Creek alluvial wells. TCC Resoonse It would appear that the most likely cause of the elevated EC readings noted at Well 008-AW3 is the migration of a TDS plume from the old spoils area directly upgradient of the well, as was previously predicted in the C-84-062 permit document. Due to the proximity of this well to the old spoils area, the presence of elevated EC readings is not unexpected for this well. DMG Concern Surface Water 1. Fish Creek from site 16 downstream, Foidel Creek from Pond A downstream, Middle Creek from M3S pond downstream, and Trout Creek from the Middle Creek confluence downstream all continue to be influenced by mining activities. The most notable influence is an increase in salinity due to mine water discharge and spoil springs. At the present time, salinity increases due to mining appear to be within the approved limits as outlined in the Probable Hydrologic Consequences section of the permit. Further review of this topic will be conducted within the permit revision (PR-03) for the Foidel Creek Mine and in conjunction with the AHR review for the Eckman Park Mine IC-81-071). TCC Resoonse No response required. DMG Concern Mine Inflow/Outflow The "1992 Mean Flow, Irrigation Period" column from Table 30 does not seem to correlate to the new data. For example, Station 8 reads .27 but data calculates .23; Station 301 reads 14.8 yet data calculates 18.53. Please explain this discrepancy. TCC Resoonse The revised Table is enclosed. As discussed, the Station 8 value of 0.27 is correct if using the period of June-September as the irrigation period, whereas the 0.23 value is correct if using the July-September period for irrigation season flows. Site 301 value of 14.8 is a typographical error, as the value originally derived was 1 5.8 cfs. However, that average value was mistakenly derived from a short data read that (upon further review) did not include the June or July flow values in the equation. The enclosed table has been revised to reflect irrigation period flows for the June-September period as discussed, along with some other minor corrections which correspond to identification of rounding errors or typographical errors.