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tests for the third quarter did indicate an elevated conductivity in the downstream well; AA1, of 2250 uhmos/cm. Beginning in 1987" the field conductivity tests and the laboratory analyses of caster samples from AA1 did begin showing some degradation of the quali- ty of water in the alluvial material. Total dissolved solids, measured in ppm, increased from the 400 to 500 range, prior to 1986, to a 1000 to 2800 range from 1987 through 1990. The water samples obtained from well AA1, from 1987 through 1990, show elevated lPVels of boron, calcium, chloride, fluoride, magnesium, nitrate, potassium, sodium and sulfate compared to water samples analyzed from AA1 prior to 1986 and compared to caster samples analyzed from AA3 cahich is upstream of the facilities area. The caater samples from well AA1 do not indicate degradation with respect to total recoverable metals. The source of the contaminants is apparently the coal stock- pile and the temporary gob piles that were constructed during the time a ramp iaas driven from the C-Seam to the B-Seam. The geo- clcemical analS•sis of the roof, coal and interburden material is presented on pages 2.04-23, 2.04-24 and 2.04-24a of the permit. Tlie contaminants listed above are generall.v all present in vary- ing concentrations in the roof, coal and interburden material and they are all water soluble. In order to analyze the impact of the contaminants on the North Forlc of the Gunnison River, the flow through the alluvium • is separated into two parts. The first is total flow based upon the total caidth of the alluvial deposit which is 500 feet. The second is the flow which is subject to contamination by the coal stockpile which encompasses an area only 150 feet wide. The flora throtagh tfie alluvium is calculated using Darcy's Law; Q = kia = kAIH/L) where; R = Flora in CFS k = hydraulic Conductivity = 0.00194 ft/sec A = Area = w width x d depth, d = 20 feet II = Potentiometric Head = 10 feet L = horizontal Distance Between Wells = 640 feet Total flow through the alluvium: Q = (0.00194)(500)(20)(10)/(640) = 0.303 CFS = 136 gpm Total flora subject to contamination: Q = (U.OU199)(150)(201(10)/(64U1 = 0.091 CFS = 41 gpm The loca flow through the alluvium indicates why well AA1 shocas signs of degradation. There is not adequate flow to flush the contaminants through the alluvium. Fortunately, the flow is low so the water which flows from the alluvium will not have a measurable impact on the quality of water in the North Fork of the Gunnison River. This fact can be demonstrated as follows: U 2