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Underlying the coal-beazing Fruitland Formation is the Pictured Cliffs Sandstone. This formation is composed of white to yellowish-gray massive sandstone ranging in thickness between 200 and 250 feet. The lower units of the Pictured Cliffs Sandstone contain increasing amounts of shales. Surface Water Conditions: The permit and adjacent areas of the mine aze located within the Stollsteimer Creek Drainage Basin, which is tributary to the Piedra River. Small intermittent and ephemeral tributaries drain the permit and adjacent areas. Stollsteimer Creek, a perennial stream, trends from east to west through the permit area and eventually enters the Piedra River. Baseline studies conducted in 1980 indicate that flows measured from October 1980 to January 1981 range from 1.3 to 1.79 cubic feet per second (cfs) at station S-1 (upstream of the mine) and from 1.5 to 3.11 cfs at station S-2 (down stream of the mine), respectively. The surface water may be classified as a mixed calcium/magnesium-sulfate/bicazbonate type water. Measurements from the monitoring period 1984-1990 indicate that the flows vazied more widely than indicated in the baseline period. Flows ranged from a low of 0 cfs to 195 cfs at station S-1. Maximum recorded flow was 300 cfs during April 1986. The streams in the azea have eroded terraces in the Fruitland and Kirtland Formations. These terraces were subsequently covered with alluvial gravels. Ground Water Conditions: Groundwater in the azea occurs in three different zones. The first zone is associated with the alluvium of Stollsteimer Creek. The second occurs in the coal of the Fruitland Formation. The third zone is associated with the Pictured Cliffs Sandstone. The Kirtland Shale, not considered a water bearing unit, overlies the coal sections of the Fruitland Formation. The Fruitland Formation is composed of shale, sandstone, and coal. Three economically viable seams were mined, the "A", "B", and "C" seams. Below the lowest seam, a layer of sandstone and shale exists between the seam and the Pictured Cliffs Sandstone. This layer is generally considered relatively impermeable. Baseline aquifer analyses were performed in September 1982. These studies determined the approximate transmissivity of the alluvium associated with Stollsteimer Creek as 100,000 gallons per day per foot (g/d/ft). Transmissivity and storativity of the Fruitland Formation were estimated from a pump test performed on wells MOO-9 and MW-10 in the Barren Ridge azea. Transmissivity of the formation was estimated at 130 g/d/ft and storativity was estimated at 1.3 x 104. Water quality in these areas was determined from water samples obtained from wells installed for baseline and ongoing monitoring purposes. Four wells each were previously installed in the Fruitland Formation and the alluvium. An additional well was installed in the spoil. Water samples obtained from wells located in the Fruitland Formation are a mixed ion calcium sulfate/bicazbonate type. Water samples obtained from wells completed in the alluvium are generally consistent with the parameters found in the water samples from Stollsteimer Creek. The water is a mixed ion calcium/magnesium-sulfate/bicazbonate type. Climate: The yeazly amount of precipitation received at the mine site can be expected to range from 15 to 20 inches. Rainfall accounts for 15 to 45 percent of the precipitation, with the majority occurring during the late spring (May) and during late summer (August and September). Mean annual temperatures range between 45 between May and September and average 73 the same period is 43 -free days' ranges from 75 to 115 days.