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CSI-013: CT. Kent Gorham memo 3 Based on the estimate that 1 cubic yard of coal fines was spread over approximately 2400 square ft. of area this equates to 0.13 inches (3 mm) of coal fines spread on the surface of the affected field. Alfalfa begins to show a sensitivity to chloride and sulfate salts at 2 mS/cm [milli-Siemens/centimeter] (Western Fertilizer Handbook 6th ed. c. 1980, Crop Salt Tolerance Study-Phase II Soltanpour, P. N., W. T Franklin, D. Mathews, et. al. 1995. This was a cooperative study conducted by CSU and DMG.) Basin Resources conducted a coal refuse leach test to characterize effluent water quality that could leach from the coal refuse. Assuming that the coal refuse leachate approximates the quality of water that could leach through coal fines, the average coal refuse leachate is 6.56 mS/cm (Golden Eagle/New Elk Coal Refuse I.eachate Study). The amount of water estimated to have breached the ditch was 5000-8000 gallons. This would allow for 3 inches of water applied to the affected portions of the field. While the coal fine leachate could potentially damage the alfalfa portion of the pasture, this effect is generally cumulative. A one time application of salt affected water of this magnitude generally would not cause significant crop damage. Addition of more water either through irrigation or precipitation will eventually wash the salts through the rooting zone. This practice is commonly used in areas having poor quality irrigation water. In the Crop Salt Tolerance Study a reduction of 50% yield in alfalfa was not observed until water quality reached a minimum of 10 mS/cm. Based on the information provided, it is doubtful that the deposition of the reported quantity of coal fines would have caused significant degradation to the alfalfa component of the pasture. As I had stated previously, both pastures were heavily dominated by Smooth bromegrass. The grass component of a pasture tends to out compete the legume component. Reseeding of the alfalfa component is often conducted every 5-10 years depending on the condition of the field. Mr. D. Chavez also expressed a concern that an apple orchard had been affected by the coal laden water. The orchard is located at the eastern extent of the Chavez property. According to the inspection report at the time of the 1994 incident the apple trees delineated the eastern extent of the area affected by the untreated mine area water. Inspection of the apple trees found 9 trees, 7 of which had already broken bud. The remaining two had viable buds but had not experienced bud break yet. All the trees were old and in need of pruning. Dead wood was prevalent in the interior of all nine trees. The mine operator had excavate 4-5 inches of soil material from the low spot where the trees are located. All 9 trees appeared viable and alive. From my background in Agronomy and experience working on salinity studies at a cooperative extension agency, I saw no evidence to lead me to conclude that the pastures or apple trees were adversely affected by the limited amount of coal fine deposition. I understand the Chavezes need for reshaping of the East-West ditch to a narrower configuration and evening out of the North-South ditch between the Deguero field and Chavez's field to the East.