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' The continental and marine shales and sandstones underlyiinq ' 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 oi` the property, the supposed exit point for any F seam waters dt~e ' to the stratigraphic dip. Thus, this coal seam does not eippear to be an aquifer. There are 21 springs on seeps occurring within or adjacent to the Paz' Mine ' permit area. Refer to Drawing 2.04.7(2)(a)-1. Diost springs appear to issue {rom the valley sides roughly at the contact of the bedrock with *he 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 45~ ' 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 t 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. ' ?'bus, 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. .~ ' REC'ISEn Mal 15, 1981 31