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<br />Sea~ags Sources Wkhln the West Pk Excavation <br />Ths Division of Minerals and Geology has expressed conoerne regarding the <br />source of water for the seepage which has occurred near the Weat Pk Pond, <br />speclflcally it the seeps are related to Impoundment of water wkhln the current <br />excavation, whether future condklons after reclamation will IneroaBe/decrease <br />seepage, and K sealing of the coal aeama la required. The inetora which will effect <br />these eoneeme Include the ortentstlon/elevatlon of the coat seams (or sandstone <br />layers), the drain outlets, and other mine features. <br />An in-pk ramp was previously eonatructed In the Weat Pk excavation which <br />Impounded water In the northern portion of tho pk at about elevation 7085. <br />Stratlgraphlc connediona between the pk area end the pond area aro very <br />approximate. Based on the estimated dip k le_ os lashe~ffietlmpoundmettt was <br />theoretically tonne-ic~ ed to the observed seeps. Observatlo_ns by Colowyo psroonnel <br />in-dated that eeepaga rataslncroa6ed-wkh preclplfatlon levels. This observation, <br />eombinsd wkh the comparatively high preeipketlon amounts during the spring of <br />1995, Indicate the moat likely source of eeepaga la preclpkatlon which recharges <br />sandstone seams and croatea a perched water zone above Isss permeable <br />clayetone/siltstons aeama. In any case, the water Impounded by the ramp hap basn <br />removed and the ramp will be slotted and the underdrefii extended through.the ramp. <br />Excavation (pk development) will soon proceed to depths (F-seam) where water <br />which collects In the base of the Weat Pk excavation will seep through bedrock <br />tones whleh do not outcrop above the base of the drainage or the Weat Pk Pond <br />and will na longer present a concern to this area. <br />rivo drain outlets ere planned, the main flII underdrein and an outlet tlraln <br />where the excavation will cross Eeet Taylor Creek. The approximate locations end <br />elevations ors shown on Flg. 1. 7'ha excess spoil fill In the East Taylor Creek area <br />hoe been a-Iminatsd from the current mine plan. The underdraln (elevation = 7040± <br />at the north edge of the Went Pk excavation) and the East Taylor Creek Outlet <br />(elevation ~ 8990 will provide an outlet for water which Inflitretes the spoil fill, <br />should k build up to these levels. Based upon this configuration we believe k will <br />only be necessary to seal coal seama~~ ro betdw slsvatlon 6990, Conversely, <br />k will not be necessary fo seal coal aeama which do not outcrop in the Weat Pk pond <br />area, Instead passing below this nrea. Colowyo provided tho estimated outcrop <br />loeatlon of the Y! seam as shown on Flg. 1. The X seam Is about 76 feet below th• <br />Y, seam. Based upon this, we have developed the fallowing conclusions: <br />Coal seams below the Y~ end Y~ seams will nat require sealing since <br />they pass below, and tlo not outcrop In the West Pk Pond srsa. <br />2. Sealing of the Y, or Y~ seam could be required where they exist at <br />elevatlvns below 6990 feet, since the Eest Taylor Creek drain outlet <br />should prevent water buildup above this level. <br />COLOYrfO GOAL COMPANY L R <br />CnJr aom q <br />5 tt:65499i;8E0E «NOSdWOHl/110 Wd85:Z 58-9 -L NOSdWOHl/l10:A9 1N3S <br />