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-32- ~U1 ~ _ fragment size distribution of caving overburden and coal strata; 4) the exposed surface areas of roof, floor, coal faces, and coal pillars; 5) the geochemistry of the rock dust used; 6) mining debris left in the mine; 7) the chemistry of back-stowed wastes; and 8) the residency time of mine waters before disc hargirtg to the surface waters or to the overlying or underlying ground water aquifers. The "f" and "P" seams contain low sulfur contents. Organic sulfur predominates, ranging between 0.32% and 0.61%, with a mean of 0.45%, in the "F" seam, and between 0.23% and 0.50%, with a mean of 0.32%, in the "P" seam. Pyritic sulfur is low and varies between 0.03X and 0.32%, with a mean value of 0.09%, for the "F" seam, and 0.02X and 0.09%, with a mean value of 0.05%, for the "P" seam. Only one sample of the "P" seam coal had a sulfate concentration of 0.01%. All other samples had sulfate levels below detection limits. Sulfur analyses conducted by the applicant indicate that the coals have low acid-forming potential. Thus, the exposed coal seams within the mine workings will not form acid mine waters. However, other associated and affected strata may be acid-forming. There are no sulfur form analyses for the roof, floor and interburden for the "F" seam coal (Eagle No. 5 mine). In lieu of conducting geochemical analyses of the roof, floor and interburden associated with the "f" seam coal, the applicant has proposed to periodically monitor the water quality in the new sump constructed within the Eagle No. 5 Mine. The applicant submitted to the Division copies of the laboratory analyses of fresh mine inflow water and sump water collected 54 days after the company began filling the sump. Laboratory results are contained in Tables 1 and 2 of the company's November 15, 1983 stipulation response submittal. An analysis of the results of the study are contained on pages IV-126 through IV-128 of the revised permit application. The results of the sump study show no significant changes in mine water quality. The sump study may closely simulate short term stagnations of mine inflow waters during mining. During mining, the residence time of inflow waters will be minimal, since constant discharging of mine water will be needed to maintain the operation of the mine. The inflow water will have a minimal time to chemically react within the mine workings. This will result in a slight increase in dissolved solids in waters discharged to the surface during operations. The sump study may not be representative of the post mining water quality changes, since this study may have analyzed sump water which may not have had sufficient time to react with the mine workings. The sump was being filled during the 54-day period, thus there was a continuous dilution of sump water over the period. The sump water quality may also been low owing to the point at which the sump water sample was taken. Areas closer to the source of inflow would have water qualities similar to mine inflow waters. Areas deeper in the sump may have significantly different water qualities.