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1 s <br /> August 1996 Monthly Report <br /> Page 3 <br /> The Colorado Historical Society determined that certain <br /> features at the site are eligible for the National Register <br /> and have requested they be preserved. Progress towards <br /> surface remediation according to the work plan has been <br /> awaiting resolution of these issues. The Corps of Engineers <br /> Section 404 permit is conditioned on an approved preservation <br /> plan. If these issues cannot be resolved in the near future, <br /> SGC may not be able to accomplish any surface remediation work <br /> until construction season next year. <br /> In order to move the permit acquisition phase of this project <br /> past the stalled position that exists presently, SGC ran <br /> stormwater exposure testing on nine of the different mine <br /> waste piles (only mill tailings piles were tested previously) . <br /> The purpose of these tests was to quantify the potential for <br /> these piles to impact stormwater. If a large potential <br /> existed, the County would be likely to approve the work plan <br /> and issue the Land Use Permit and the Colorado Historical <br /> Society would be more inclined to accept the need for <br /> potential damage to the tram loadout structure in order to <br /> remove a threat to water quality. The test results do not <br /> indicate this is the case. The average test result zinc <br /> loading from stormwater type exposure (ie 240 ug/1) was close <br /> to water quality goals for the Animas River at A-72 . SGC is <br /> submitting a proposed method of reconciling this issue and <br /> will need timely approvals for this project to proceed. <br /> Monitoring results are attached. <br /> Longfellow - Koehler Mine Waste Project <br /> During the month of August, the Section 404 Permit required <br /> for project implementation was received and efforts were <br /> concentrated on capturing and containing portal flows in order <br /> to isolate them from other potential site flows. This is <br /> important for site characterization and remediation design. <br /> The Koehler portal was opened and the access timbered. No air <br /> movement existed and bad air was encountered approximately <br /> 400-600 feet into the tunnel. Therefore, water sources within <br /> the tunnel could not be identified. A concrete cofferdam was <br /> constructed to divert the flow into an 8 inch diameter drisco- <br /> pipe. This pipe was extended around the Koehler pond in order <br /> to determine if additional flow sources exist. <br />