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The impacts of pit excavations and pit pumpage on the overburden, <br />coal, and underburden aquifers appear to be of minimal <br />significance. The overburden and coal units are artificially <br />saturated and recharged. Measurable drawdowns are limited to the <br />areas within and immediately adjacent to the pits. There are no <br />local wells completed in the overburden and coal units within a one <br />mile buffer of the mine and the underburden aquifer is unaffected <br />by the pit excavations. <br />A review of the water quality of the overburden, coal, underburden, <br />and spoils aquifers has indicated that the water is unsuitable for <br />domestic use. Hardness, iron, magnesium, sulfate, and TDS levels <br />are all significantly above those levels recommended for domestic <br />drinking water. Water quality in the four aquifer types is <br />suitable for livestock drinking water, excepting the coal and <br />spoils aquifers. Sulfate and TDS levels in the coal and spoils <br />aquifers make it marginal to unsuitable for livestock drinking <br />water. <br />• In summary, the significance of elevated levels of salts migrating <br />into undisturbed portions of the overburden, coal, and underburden <br />aquifers previously mentioned is minimal for the following reasons. <br />The aquifers have very low transmissivities and'. would not produce <br />significant yields for extended periods of time. The continuous <br />influx of recharge from the irrigation ditches should rapidly <br />dilute elevated concentrations migrating from the resaturated <br />spoils areas. Even if no dilution was assumed, one hundred percent <br />increases in TDS levels would not render the overburden and <br />underburden aquifers unsuitable for livestock water. Finally, the <br />coal aquifer is already marginal to unsuitable for livestock water. <br /> <br />107 <br />