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2.04.5(1)(b) The continental and marine shales and sandstones underlying the coal bearing zone on the property have a potential recoverable ground water supply of zero (0) to 600 acre-feet of water per square mile, depending on strata thickness. In more than 80 exploratory drill holes on the ARCO property, there is no indication of water in the F seam. There are no known springs issuing from the F seam on the north side of the property, the supposed exit point for any F seam waters due to the stratigraphic dip. Thus, this coal seam does not appear to be an aquifer. There are 21 springs on seeps occurring within or .adjacent to the Sear Mine permit area. Refer to'Drawing 2.04.7(2)(a)-1. Nbst springs appear tO issue fran the valley sides roughly at the contact of the bedrock with the thin alluvial cover of the valley bottom. A few issue from sandstone ledges a few feet up the valley wall above the soil or alluvial cover. Production varies from 0.1 to as much as 50 gallons per minute with 454 . of the measured springs producing less than one gallon per minute with 12~ producing from 10 to 50 gallons per minute. Production apparently decreases from a total of 300 gallons per minute in the early summer to less than 200 gallons per minute by fall. Recharge to the springs appears to come from snow melt. The Mesaverde sandstones and the fracture system within these sandstones is the apparent aquifer. The outcrop- ping rocks consist of interbedded lenticular sandstones and shales of stream channel and floodplain origin. The sandstones, which have low permeability, act as the aquifers, while the shale layers act as barriers to vertical migration of waters. Thus, each sandstone is a potential aquifer which may or may not be perched by the underlying shale members. Perched water tables or aquifers appear to be the rule. ~J REVISED Pray 15, 1981 5-4