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Npdrolagic Data /merpreratian and /mpatt Atsessmen! for the Permit and Adjacent Areas • solids late in the year). GP-1 samples probably indicate some leaching or seepage from the pile (the high concentrations of iron in Sylvester Creek might have raised iron reading in the water recharging GP-1 to some extent). Readings from SG-1 do no indicate significant quantities of iron o~ manganese are migrating into the alluvial groundwater. In addition, average concen- trations of iron and manganese dropped from WY 1992 values (perhaps attributable to higher flows due to the deep snowpack and higher runoff of WY 1993; or, localized higher concentrations of these elements have been flushed from the system. The impact to alluvial ground water from the refuse pile SOM-13 and SOM-80 have (however, these two wells did not experience a seasonal fluctuation in water levels between 1988 and 1992). The effects of the wet WY 1993 were reflected in Wells SOM-13 and SOM- 'h,~$0, but not in B-32. Although well infor- ~ ~~ mation does not preclude establishment of a hydraulic connection via cracks in subsided overburden, no variance in spring flows have been recorded. At this time, the hy- pothesis that current mining has had little affect on shallow groundwaters within the Barren Member appears to be substantiated. "F" Seam probably remains low. 7 Barren Member Shallow wells include SW-1 through SW-6 (drilled to monitor the effects of subsidence) and B-32. Except for a June measurement in Well SW-1, all wells SW-1 through SW-6 were dry (or moist, or so little water as to not permit sampling), and have been since they were drilled. Water levels dropped nearly twenty feet in Well B-32 during 1980 and 1981, continued to show a gradua] and continuing slower lowering (10 feet) until WY 1992, and have leveled off to date. However, this well has collapsed at a depth of approximately sixty feet, and recent values probably indicate only that ground water levels are not higher than recorded measurements. Water levels dropped nearly fifty feet in Well SOM-13, a deeper well, during 1980 to 1981 and has stabilized since. Except for the portal areas, no sig- nificant inflow of water has been seen in "F" Seam mined areas. If mining activities were a cause of the historic dewatering, apparently a hydraulic equilibrium is being reached. In general, water levels in B-32 have not shown a seasonal fluctuation, wells 13 "F" seam wells SOM-2 and SOM-16 show no seasonal or annual fluctuation and appar- ently have little or no surface water connec- tion. They also exhibit a hydraulic equilib- rium over the last couple of Water Years. As there is no apparent hydraulic connection between the "F" (where there is no activity) and the "B" (where there is mining activity) Seams, no change in this steady system is anticipated. "E" Seam The "E" Seam is located below the inactive (mining) "F" Seam and above the active "B" Seam. Well 23-H-2 has maintained a consistent water level, and appears to be not affected by seasonal precipitation or mining activities. "B" Seam The "B" Seam was mined during WY 1993. Water levels in well C-72-H remain con- stant, showing no dewatering impact to date. Water levels in SOM 127-H started drop- ping in WY 1992 (by 25 feet through WY 1993). SOM-127-H was abandoned in the field in June, 1993 and was replaced by