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<br />r 1 <br />LJ <br />l J <br />2.0 Hydrologic Dara /nrerprerarion and Impart Astessmna for the Perrtir and Adjacen! Areas <br />activities. This spring had no flow (except <br />for 0.03 gpm 04/23/95) this WY. Persistent <br />WY 1994 flows of 0.5 gpm dropped to no <br />flow in October of 1994 (Graph F-7). <br />2.3 ASSESSMENT OF <br />GROUNDWATER <br />Wells remained fairly constant compared to <br />previous years. However, two wells located <br />south of mining in the F-seam, SOM-2-H <br />and SOM-23-H-2, exhibited water level <br />changes. SOM-C-72-H was undermined in <br />1994 and began to recover in WY 1995. <br />2.3.1 Alluvial Wells and the <br />Lower Refuse Pile <br />In 1994, MCC produced 101,678 tons of <br />reject material. Currently there is a total of <br />938,546 tons of material in the Lower <br />Refuse Pile. <br />Data suggests that no potentiometric surface <br />has developed in the refuse pile fill as GP-3, <br />GP-4, and GP-5 are still dry. This may be <br />due to the low vertical permeability of the <br />refuse pile materials and the small quantity <br />of water available for recharge due to <br />effective surface water drainage from the <br />pile. <br />Alluvial well GB-1 (a replacement of SG-1 <br />in previous reports) is sited to monitor <br />groundwater east of the lower refuse pile. <br />Conductivity ranged from 1010 - 1166 <br />mmhos/cm (Table G-5). The hydrograph <br />(Appendix H) for GB-1 reflects the wet <br />spring. <br />2.3.2 Barren Member <br />There were no significant changes in water <br />level in Barren member wells during the <br />AHIL-95.210/OS/15/96(1:38pm) <br />17 <br />WY. Shallow wells include SW-1 through <br />SW-6 and B-32. Wells SW-2, SW-4, SW-5 <br />and SW-6 were dry or had so little water as <br />to not permit sampling and have been so <br />since they were drilled. Water levels rose <br />sufficiently in the spring to sample SW-1 <br />and SW-3 (Tables G-12 and G-14). Well B- <br />32 has collapsed at a depth of approximately <br />sixty feet, five feet above the bottom of the <br />well. Water levels rose sufficiently in this <br />well to obtain samples during [his WY <br />(Table G-8). <br />Historically, water levels in B-32, SOM-13, <br />and SOM-80 have not shown a seasonal <br />fluctuation. Water levels did drop nearly <br />fifty feet in Well SOM-13-H, a deeper well, <br />during 1980 to 1981 and has stabilized <br />except for a twenty foot rise and fall during <br />WY 1993. SOM-80-H also demonstrated a <br />rise and fall in water levels during WY <br />1993. This WY, SOM-13-H showed no <br />seasonal fluctuation, and SOM-80-H <br />exhibited a very slight rise of less than two <br />feet. <br />All analytical sampling for wells SOM-13-H <br />and SOM-80-H were within baseline ranges. <br />SOM-38-H-1 was reported lost in 1994. <br />Although obstructions still prevent sampling, <br />water levels were obtained during this year. <br />SOM-38-H-1 was undermined by <br />underground mining activity. Water <br />readings at historic levels indicate integrity <br />and low permeability of overlying <br />formations. <br />No significant inflow of water has been seen <br />in "F" Seam mined areas except for the <br />portal areas. If mining activities were a <br />cause of the historic dewatering, apparently <br />a hydraulic equilibrium is being reached. <br />Although well information does not preclude <br />establishment of a hydraulic connection via <br />