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levels in [lie overburden aquifer and the base of active pits and the low permeability of the overburden aquifer, .round.+•ater inflows to the pits were minimal. • The mining operation resulted in a lowering of the potentiometric levels in the Wadge Overburden aquifer immediately adjacent to the active pit areas. The low groundwater inflow rates, low permeabiliq- of the aquifer, and small available drawdown resulted in relatively insignificant effects downdip from the mining operation. Drawdown effects will be temporary, with water level expected to recover close to the pre-mining conditions within a few years of final reclamation. An illustration of the effects of mining and reclamation on adjacent potentiometric levels is given by the data from Well 009-79-4, completed in the Wadge Overburden. A plot of water level versus time, as shown by Permit Renewal Figure 7, Wadge Overburden, Period of Record Water Level Data, shows a marked drop during mining of adjacent updip area followed by a gradual rise to pre-mining levels as recharge through the reclaimed backfill .vas reestablished. Chanties in Aquifer Rechartie Characteristics •Tlte method of surface mining practiced at the Eckman Park operation resulted in temporary, localized increases in the permeability of [he spoil material and possible increases in [he aquifer recharge capacity. There was a temporary decrease in recharge to downdip bedrock aquifers during mining due to interruption of groundwater flows in the active pit. As reclamation of disturbed areas is completed, the combined effects of compaction and settlement may result in reduction in permeability of the spoil material to values which approach pre-mining conditions. Studies performed by Lusby and Toy (1976) indicate that reclaimed areas may actually have lower infiltration capacities than undisturbed lands. 1996 Permit Ren. Permit Renewal 780-144-22 Revised 3/18/97