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3. Previously Established Numeric Protection Limits <br /> DRMS has issued NPLs for the CC&V mine site four times over the last eleven years. In issuing these <br /> NPLs, DRMS personnel must be presumed to have complied with the Division's regulatory mandate to <br /> use its best professional judgment in analyzing the submitted data to determine NPLs that deviated from <br /> the criteria in Tables 1 through 4 of WQCC Regulation 41, The Basic Standards for Groundwater. In <br /> using their best professional judgment, DRMS personnel appropriately determined that the groundwater <br /> quality of the sites reviewed was not impacted by sources of groundwater contamination since January 31, <br /> 1994, and therefore the observed groundwater quality is representative of water quality prior to January <br /> 31, 1994. <br /> DRMS issued NPLs to CC&V via letters on the following dates: October 7, 1996; November 20, 1998; <br /> May 18, 2006; and August 7, 2012. NPLs received on October 7, 1996, pertain to all groundwater <br /> monitoring locations at the CC&V mine site and set numerical protection limits for the following <br /> analytes: aluminum, arsenic, cadmium, copper, fluoride, iron, lead, manganese, mercury, nickel, nitrite, <br /> nitrate, nitrate+ nitrite, selenium, zinc, cyanide (WAD), and pH. On November 20, 1998, DRMS issued <br /> NPLs pertinent to monitor wells CRMW-3B-63, GVMW-8A-250, and WCMW 6-234 that contained <br /> NPL values for manganese, cyanide (WAD), pH and sulfate. On May 18, 2006, DRMS issued NPLs for <br /> Vindicator Valley compliance well VIN 2B, which included NPL information for manganese, cyanide <br /> (WAD), pH and sulfate. On August 7, 2012, DRMS issued updated NPL information for WCMW-6 and <br /> new NPL information for WCMW 3-134, which included NPL values for manganese, zinc, cyanide <br /> (WAD),pH, and sulfate. <br /> Documentation received from DRMS for the CC&V mine sites' NPLs for the above-referenced dates are <br /> included within Attachment A. Table 2 below presents the current DRMS approved NPLs for the CC&V <br /> mine site and the associated most restrictive Colorado Regulation 41 Ttable Value Standard (Reg 41 <br /> TVS) for the listed parameters. <br /> 7 <br />