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• Venture Resources is confident that one of the results of the proposed operations beginning to make a positive <br />difference in reducing heavy metal migration from abandoned mine waste rock dumps to the watershed. This <br />project extracts nearly all of the acid-forming minerals and heavy metals within the waste rock that are the source of <br />acid-runoff that plague this historic mining district. By doing nothing, these piles of pre-existing waste rock will <br />continue to leach acid and heavy metals for a very, very long time. But, by designing a carefully regulated and <br />engineered program a solution can be achieved. <br />Venture Resources wishes to assert again that a Colorado Discharge Permit is not required because there is zero <br />process water discharge to surface waters and the process water is nearly 100% recycled back to the mill. <br />6.4.20(11)(c) <br />The attached water quality data was collected and analyzed by the US EPA and the CDPHE. The DRMS should <br />feel confident that the analytical detection limits are acceptable. <br />6.4.20(12) <br />A water quality monitoring plan has been set forth in this Exhibit T, 6.4.20(7)(d) and in Exhibit C, 6.3.3(2)(b). <br />6.4.20(13)(x) <br />Refer to 6.4.20(7)(f) for reserve capacity of containment facilities. <br />The average pan evaporation rate exceeds the average precipitation rates in this vicinity (refer to the corresponding <br />climatic data attached as an appendix to this Exhibit T) when considering long term water balance. <br />6.4.20(13)(b)(i) <br />Monthly precipitation totals for this region have been collected, as reported by NOAA, for: <br />• Georgetown, Clear Creek County, CO for a period of 1948 - present <br />• • Idaho Springs, Clear Creek County, CO for a period of 1948 - 1.974 <br />This data is attached within the appendix of this Exhibit T. <br />6.4.20(13)(b)(ii) <br />Average windspeed and prevailing direction have been collected for Boulder/Jeffco Airport ... the closest station. <br />This data is attached within the appendix of this Exhibit T. <br />6.4.20(13)(b)(iii) <br />Monthly temperature data for this region has been collected, as reported by NOAA, for Evergreen, Jefferson/Clear <br />Creek County, CO for a period of 1971-2000. This data is attached within the appendix of this Exhibit T. <br />6.4.20(13)(b)(iv) <br />The pan evaporation rate for the area (as reported by the Western Regional Climate Center) ranges between 35.5 - <br />40.5 inches annually. This data is attached within the appendix of this Exhibit T. <br />6.4.20(14)(a-e) <br />The site is completely composed of crystalline Precambrian rocks, i.e. gneisses and schists, and tertiary intrusive <br />rocks such as quartz monzonites overlain by 0-24" of unconsolidated material. Base geologic information can be <br />found above in 6.4.20(8)(c), an excerpt from USGS Bulletin 1208, Economic Geology of the Idaho Springs District <br />- Clear Creek and Gilpin Counties, Colorado, Moench, Robert H. and Drake, Avery Ala, Jr., 1966. <br />The pre-existing abandoned mine waste rock to be processed consists predominately of silica & alumino silicate <br />minerals. The sand portion is composed of vein type material such as quartz gangue and quartz monzonite <br />porphyries with some of the surrounding wall rock composed of metamorphic gneisses. The clays are formed from <br />altered wail rock and feldspars. <br />The potential for acid formation exist because of the weathering of sulfide minerals present, consisting primarily of <br />iron sulfide (FeS2 or pyrite) and copper iron sulfide (CuFeS2 or chalcopyrite). These are the minerals to be removed, <br />Page 27 of 31