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Mr. B. Oswald <br />11!27102 <br />Page 2 of 3 <br />Problem / Issue #2: "Road access to trespassers is apparently available across 9700 <br />level pipeline. It appears that travel by such unauthorized traffic would damage the <br />geomembrane below the rip-rap cover, thus affecting the integrity of the pipeline <br />system." <br />Response: Vehicular access across the overflow channel overlying the pipe system will <br />be blocked in Spring, 2003 when ground and weather conditions allow. We will most <br />likely use crock/boulder berm across the access road to prevent vehicle access to the <br />referenced area. <br />Problem I Issue #3: °Most surface drainage to the lower tailings pond will pond there <br />and seep into the tailings. The depression is below the invert of the bypass, apparently <br />in nonconformance with the reclamation plan. At issue is whether this seepage will <br />compromise integrity of the failings dam, and whether it will affect ground water quality." <br />Response: An engineered permanent spillway breach along the eastern groin of the <br />lower tailings embankment was constructed in 1993 after communication and <br />correspondence with DMG regarding the spillway construction as part of an amendment <br />/technical revision process under the DMG reclamation permit. At that time, a bottom <br />elevation in the permanent breach was determined such that the dam facility would not <br />be entirely free-draining thus preventing the potential for release of tailings solids should <br />the breach structure ever carry flow through it. As such, the facility therefore does have <br />the potential to store a minor amount of water such as after a heavy Spring snowmelt. <br />This area is in the extreme NE comer of the stored tailings (tailwater area). The amount <br />of surtace water reporting to the tailings area is minimized by the continued functioning <br />of the upgradient diversionary ditch system to convey off-site runoff around and away <br />from the tailings storage area. <br />The permanent breach design also addressed the issue of geotechnical integrity and <br />stability of the tailings embankment and the breach itself as a component of final <br />reclamation and closure for the site. <br />Reference should be made to the geochemical and geotechnical evaluation conducted <br />on the upper and lower tailings facilities under TR003 of the DMG reclamation permit <br />(see Shepherd-Miller, Inc. report, `Eva/nation of the Upper and Lower tailings Ponds at <br />the Bulldog Mine", April, 1997) with regard to the potential for precipitation water, or <br />temporary water pooling in the area as described above in the tailwater area, to result in <br />affects to ground-water quality from seepage through the in-situ tailings. This study <br />addresses the issue in some detail and resulted in a determination that affects to ground <br />water would not be of concern given current and future saturation conditions and <br />infiltration potential of the tailings associated with water contacting and/or moving <br />through the tailings material.. Conditions at both tailings facilities have not changed since <br />that time nor are they expected to change in the future with one exception -the lower <br />tailings material surface has been recently topsoiled and will be revegetated after <br />seeding is completed in Spring, 2003, The topsoiling and revegetation work on the <br />lower tailings surface area will further reduce water infiltration potential into the tailings <br />material. <br />8719-D ACADEMY RDAD NE, AL6uquERquE, NM 87/09 TELE: (5051 B2B-1821 FAX: (5061 B2 B•1826 <br />