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to as the Wadge Lennox interburden. These wells exhibit normal seasonal vaziations. Aquifer tests performed in the Wadge Coal seam indicate that the Wadge aquifer exhibits asemi-confined condition with a transmissivity value of 377.1 gallons per day per foot {gpd/ft). Wadge water levels; dependent upon well proximity to the recharge area, show some seasonal variation. Alluvium There are three alluvial aquifer systems within the Seneca II permit area: the Grassy Creek alluvial aquifer, the Cow Camp Creek alluvial aquifer system (drainage from below 004 pond to Fish Creek), and the Bond Creek alluvial aquifer (drainage from below 008 pond to Fish Creek). The Fish Creek alluvial aquifer is not within the Seneca II permit area, but may be affected by water discharging from the permit area. Nine wells aze used to monitor alluvial water quality in the drainages. Two wells aze located along Cow Camp Creek, one along Bond Creek, two along Grassy Creek and four along Little Grassy Creek. All of these wells exhibit seasonal variations. The Grassy Creek alluvial system is down gradient ofmining and the wells were constructed after mining in the Grassy Creek drainage. Progressing downstream, the little Grassy Creek alluvial aquifer becomes increasingly affected by spoils water discharge. Spoils The resaturation of portions of the backfilled pits has been expressed as spoil aquifers. Water percolates through the replaced spoil material and flows down-gradient until it reaches the lower-most highwall where the infiltration rate into bedrock is much lower than flow through the spoil. When the elevation head of the spoil aquifer exceeds the ground surface elevation, the spoil water dischazges in the form of springs at the topographically lowest point along the reclaimed highwall. Nine spoil springs have been identified, eight of which are monitored by Seneca Coal Company. In addition, Seneca Coal Company has historically monitored thirteen spoil wells as part of the approved monitoring plan. Water from the spoils exhibit elevated concentrations of sulfate, manganese, and magnesium. TDS concentrations in water from spoil wells have generally risen during the period of monitoring but seem to level out at about 4000 mg/1. Several exceptions are S25-S, which has reached concentrations as high as 5700 mg/l, S26-S which reached levels as high as 4300 mg/1 but has dropped off to azound 3500 mg/l, and S27-S which has climbed gradually to about 3300 mg/1 TDS. Spoil springs show the same range of concentrations as the wells. In 1977, the Water Resources Division of the United States Geological Survey (IJSGS) began a lysimeter study at the Seneca II Mine to determine spoil aquifer dischazge quality, and how that quality changes over time. Stipulation No. 23 in the original 19