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3. Method 6010B (ICP-AES) is not adequate for analysis of the extraction leachate from the TCLP test <br />because the detection limits are too high. The DLs for 6 of the 8 elements in Evergreen's analytical <br />report are actually higher than the Colorado regulatory limits. Method 200.8 (ICP-MS) should be <br />used for metals, and has adequate detection limits to meet the state regulatory standards. <br />4. The list of analytes must be expanded beyond the 8 done in the TCLP, to include a more complete <br />suite of regulated parameters. Refer to Reg 31 and 41. The Division recommends the following for <br />metal mining sites: <br />a. Include all parameters listed on Table 1 through 4 in CDPHE Regulation 41- Basic Standards for <br />Ground Water. Omitting Total Coliforms, Asbestos, Free Cyanide, Chlorophenol, Color, <br />Corrosivity, Foaming Agents, Odor, and Phenol. <br />b. Include all parameters on Tables I through III in CDPHE Regulation 31- Basic Standards and <br />Methodologies for Surface Water. Omitting D.O., Suspended Solids, Temperature, E. Coli, Total <br />Residual Chlorine, Free Cyanide, Sulfide, and Asbestos. <br />5. The testing must include pH and conductivity in the analysis of the SPLP extract. These must be <br />analyzed in the lab immediately after the extraction. <br />6. The Operator may be able to meet the "quantities sufficient" Rule 7.2.6(1). They still need to <br />characterize the ore using the SPLP, but regardless of the results, if they can commit to keeping ore <br />storage to a minimum in terms of quantity or time, or provide adequate measures to prevent <br />release of contaminants, then the Division would not require a DMO designation. <br />The Operator is required to document the ore stockpiles do not have the potential to produce acid <br />mine drainage no later than September 24, 2009 therefore, your response to this review should be <br />submitted to the Division as soon as possible. <br />If you have any questions, please do not hesitate to call me at 303-866-2555. <br />Sincerely, <br />Peter S. Hays <br />Environmental Protection Specialist <br />cc: Steve Shuey; DRMS <br />David Bird; DRMS <br />Tom Hendricks; Calais Resources Colorado, Inc.