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Peabody Coal may wish to aciculate increased floa+ in Fish Creek, based upon data presented in Table 7-56. Surface contributions within the Cow Carnp Gnd 5ond (reek drainages, based upon a calculation comparing current 004 pond discharge with spoils springs inflow, may also be used in the computation. RESPONSE: As a result of discussion between Peabody Coal Compan}~ and MLRD hydrologists on September 30, 1486, the following assumptions are used to predict surface and ground water impacts to Fish and Grassy Creeks: (1) In early summer, during the month of June, surface water flow past outfalls 002 and 003 in Little Grassy Creek, 004 in Cow Camp Creek, and 007 in Bond Creek, will be in part contributed by mine spoils discharges. During July, August, and September, flow will be sustained solely by mine spdiis discharges. (2) The TOS concentration of mine spoils discharges will be representative of mine spoils water quality. The duality of spoils well G;;-S27 ti•+ill be cor.sidereo representative or spoils discharge in Little Grassy Creek and the quality of Spoils Spring ~1 will be considered representative of spoils discharge in Cow Camp and Bond Creeks. (3) The flow component of mine spoils discharges in Little Grassy Creek will be the combined mean flow for each of the summer months determined from continuous flood data collected since 1481 to date at NPDES outfalls 002 and 003. In Cow Camp Creek, the flow component of mine spoils discharge for June rill be the highest recorded mean daily flaw because of the more limited historic floo-+ record. Flory in July o-+ill be the highest predicted base rlorv from NPDES outfall 004 (0.2 cfs). because of the similar drainage and disturbance area of Bond Creek, the June and July floo+ from outfall 007 in bond Creek will be the same as that for Cow Camp Creek. • During the months of P.uaust and September, flow past outfalls 004 21