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11/27/02 OB:al '$5058281828 <br />BARRICIi-AB9 <br />Mr. B. Oswald <br />11!27102 <br />PBgr; 2 of 3 <br />Problem / Issue #2: °ROad access t0 trespassers is apparently available across 9700 <br />level pipeline. It appears that travel by such unauthorized traffic would damage the <br />geomembrane below the r/p-rap cover, thus affecting ttre integrity of the pipeline <br />system.' <br />Response: Vehicular access across the overtlow channel overlying the pipe system will <br />be blocked in Spring, 2003 when ground and weather wnditions allow. We will most <br />likely use crock/boulder berm across the access road to prevent vehicle axes to the <br />refererired area. <br />Problem / Issue #3: 'Most surface drainage to the lower tailings pond wr7l pond then: <br />and seep into the tailings. The depression is below the invert of the bypass, apparently <br />in nonCOnfO-manCe with the rt'clamation plan_ At issue is whether this seepage will <br />compromise integrity of the tailings 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 reganiing 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 entirelyfree-draining thus preventing the potential for release of fallings solids should <br />the breach structure ever carry flow through it. As such, the facility therefore does have <br />the poterttlal to store a minor amount of water such as after a heavy Spring snowmerc. <br />This area Is in the extreme NE comer of the stored tailings (tailwater area). The amount <br />of surface 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 geotechnlcal 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 geoteehnical evaluation mnduded <br />on the upper end lower tailings taalities under TR009 of the DMG reGamation permit <br />(see Shepherd-Miller, Inc. report, 'valuation ofthe Upper and LowertailingS PendS at <br />the Bulldog Mfie", April, 1997) with regard to the potential ror predp'rtatlon water, Or <br />temporary water pooling In the area as described above in the taiNvater area, to resole 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 firture 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 fatilifies 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 lie revegefated after <br />seeding is completed in Spring, 2003. The topsoiling and revegetation work on the <br />lower fallings surfaoe area will further reduce water infiltration potential into the tailings <br />material. <br />I~ooa <br />6')10.0 AE.°per.,v ROAD N6. ALOVOYLRG Yi. NM 67109 TsLi116061 628.1621 FAXt 1~lO~1 earl-lean <br />