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tests for the third quarter did indicate an elevated conductivity in the downstream sell; AA1, of 2250 rihmos/cm. Beginning in 1987 the field conductivity tests and the laboratory analyses of water 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 sell AA1, from 1987 through 1990, show elevated .levels of boron, calcium, chloride, fluoride, magnesium, nitrate, potassium, sodium and sulfate compared to raster samples analyzed from AA1 prior to 1986 and compared to water samples analyzed from AA3 rahich is upstream of the facilities area. The water samp.Les 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 mere constructed during the time a ramp was driven from the C-Seam to the B-Seam. The geo- chemical analysis of the roof, coal and interburden material is presented on pagesL.04-23, 2.04-24 and 2.04-24a of the permit. The contaminants listed above are generally all present in warp- ing concentrations in the roof, coal and interburden material and they- are a1J raster soluble. l.n order to analyze the impact of the contaminants an the North Fork of the Gunnison River, the flow through the alluvium is separated into two parts. The first is total flow based upon the total width 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 flow through the alluvium is calculated using Darc,y-'s Law; Q = kia = kAlll/L) where; R = Flow in CFS k = Ilydrarr.l.ic Conductivity = 0.00194 ft/sec A = Area = w width x d depth, d = 20 feet ff = Potentiometric Head = 10 feet L. = horizontal Distance Between Wells = G40 feet Total flora through the alluvium: q = (0.00194-(5001120)(101/(640) = 0.303 CFS = 136 gpm Total flora subject to contamination: Q = (0.00194)(150)('LO)(10)/(640) = 0.091 CFS = 41 gpm The lora flora through the alluvium indicates why sell AA1 shoras signs of degradation. There is not adequate flow to flush the contaminants through the alluvium. Fortunately, the flow is lora so the raster which floras from the alluvium mill not have a measurable impact on the quality of water in the North Fork of the Gunnison River. This fact can be demonstrated as folloras: 2