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<br />The 1311 Method, SW-846, Nov. 1990, is found in 40 CFR 261, Vol. 55, No. 126, <br />June 29, 1990. The 1312 Method, more recently used, has three alternatives: <br />Solution 1 -Used east of the Mississippi River <br />Solution 2 -Used west of the Mississippi River <br />Solution 3 -Used for material exposed to cyanide <br />Some additional information on TCLP tests is attached for reference. <br />4. Column tests were conducted on the most prevalent type of Cresson Ore (Type <br />I -low grade). The tests were first for determination of gold recovery and, <br />following this, for detoxification utilizing water only. The spreadsheet results are <br />attached as they formed the basis for reclamation detoxification costs submitted <br />with the permit application. Currently, testing is being conducted by an outside <br />firm for bio-remediation. Although the initial findings are encouraging for <br />decreasing de-tox time with water only, no hard figures are available at this time. <br />The operator feels that the fresh water rinse represents "worst case" and, <br />therefore, used these figures for reclamation costs. <br />In addition to the detoxification test results, TCLP results are attached. These tests <br />were run under Method 1311. Currently, samples are being analyzed using <br />Method 1312, Solution 3. The results will be forwarded to the Division as soon as <br />they are received. <br />5. Four additional Acid/Base Potential Tests are attached. These indicate little <br />potential for acid generation. Location collars of all core holes from which <br />acid/base potential samples were taken are shown on the attached map, Drawing <br />D6. The holes used for test material were all angle holes so the plan position of <br />the sample locations is more widely spread than the collar positions indicate. <br />Please refer to the Adequacy Letter Response, page 8, for details of handling <br />waste rock to mitigate any acid rock drainage. <br />Sincerely, <br />!?T~. <br />dgarT.~Hunter <br />Manager, Permits & Cultural Resources <br />ETH/kl <br />addtlinf.319 <br />Enclosures <br />pc: Jim Muntzert w/o enclosures <br />John Woodward w/o enclosures <br />File <br /> <br />