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r1 <br />U <br />• <br />6.4.20(8)(e) <br />Detailed above in 6.4.20(8)(b) is a description of the vein and fracture systems that underlie this area and provide a <br />hydraulic drainage connection to the Big Five Tunnel. <br />Refer to USGS Bulletin 1208, Plate 3, Geologic Section Along the Big Five Tunnel, Idaho Springs District, <br />Colorado in the appendix of Exhibit C to see this connectivity. <br />6.4.20(9)(a) <br />The groundwater in this vicinity is unclassified, per the CO Division of Water Resources. <br />The poor, pre-existing quality of the groundwater in this mining district make it a poor choice for domestic water <br />wells ... usually an attempt at drilling a well come up "dry" because the district is drained by the Big 5 and Argo <br />Tunnels. Evidence of this is the existence of (1) domestic groundwater well downgradient of our proposed <br />operation (see appendix of Exhibit Q. Many residents just north of the operations and throughout the Virginia <br />Canyon region actually haul water to cisterns for domestic use. The City of Idaho Springs constructed a water fill <br />station at the west end of town to service this sort of customer. Central City has also constructed a similar station <br />near Russell Gulch. <br />There is no agriculture to speak of in this area. Beside the fact the ground is steep, arid, and barren the County does <br />not have any Agricultural Zoning in this region. <br />6.4.20(9)(b) <br />Baseline groundwater quality has been established by sampling the drainage from the Big 5 Tunnel. This analysis is <br />included in the appendix of Exhibit C. A current lab analysis, along with the EPA analysis done in 2005 titled <br />"Explanation of Significant Differences Big Five Tunnel Discharge, Table 1.0", shows a reasonable extrapolation of <br />baseline quality. <br />TABLE 1.0 ANALYTICAL SUb MARY TABLE BIG FIVE DISCHARGE SAMPLES <br />Metals concentrations ezpressed in micrograms/Liter <br />Sampling Event As Cd Cu FigHg Mn Pb Tat <br />1985 phase I RI 10 48 1710 NAF 19,700 91 9770 <br />1989 Phase U Ri 10 27 690 NAF 18,800 S 9100 <br />2001 CDPHE NAF 24 1500 NAF 32,200 NAF 9160 <br />2005 UOSn) 2 20 2%0 0.1 191500 16 7610 <br />State Drbddn Water MCL 10 5 - 2 - <br />State Drinlda Water MCLG <br />State Second MCL <br />- 1300 <br />100 <br />- - <br />50 15 <br />S00 <br />A nudeLife NEC/W $ 0.4/3 SIY 0.01 1000/1493 4/2 471200 <br />NAF - Not Analyzed For <br />MCL - Main um Contaminant Level <br />MCLG - Mardnmm Contaminant Level Goal <br />• NEC - No Effect Concentrations an metal concentrations at which aqua& life does not suffer my toxic effects <br />(1) UOS - START contractor for EPA's,EwA%eaey Response Team <br />(2) WQCD - aquatic standards for Clear Creek Segtmeat 2 <br />21