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• z.oa.s <br />Or, commonly stated, Iron Pyrite in the presence of oxygen and water will be <br />oxidized to Ferric Hydroxide and Sulfuric Acid. This reaction may be either <br />chemical as described above or microbial. Several species of bacteria gain <br />energy from the oxidation of Iron Pyrite to form the above reaction products. <br />In oxidizing conditions at pH > 4.0, ferric oxide will form. At pH < 4.0 under <br />oxidizing conditions, a mineral called jarosite will form. Jarosite is very insoluble <br />and is not a concern. A common iron mineral, goethite, will form in small <br />amounts across the common pH spectrum under slightly oxidizing conditions. <br />If the acid produced under complete oxidation is not buffered by the surrounding <br />mineral matrix, about 625 pounds of Calcium Carbonate (lime, CaCO3) would be <br />required to neutralize 1,000 tons of material bearing 0.01% iron pyrite such as <br />in DH-12. <br />A sample of run of mine coal, from the nearby Bowie No. 1 Mine D-Seam, was <br />analyzed to determine if the D-Seam coal in the area has sufficient lime to <br />neutralize its acid producing characteristics. The D-Seam coal has a carbonate <br />. equivalent of 0.22% which equates to 4.4 pounds per ton of coal or 4,400 <br />pounds of lime per 1,000 tons of coal. This means the coal contains adequate <br />lime to neutralize coal bearing 0.07% iron pyrite (4,400 _ 625). The laboratory <br />report is presented in Volume III, Exhibit 6. <br />Other evidence the area D-Seam coal does not have acid producing <br />characteristics is the old Oliver Mine No. 1 located east of Somerset, CO which <br />mined in the D-Seam in the 1940's and 1950's. This mine is discharging water <br />that is monitored by Oxbow Carbon & Minerals as spring 8. This "spring" water <br />consistently has a pH in excess of 7.0 (ref. OCM 1994 Annual Hydrologic <br />Report). <br />Based on the above discussion, it is likely lime is present in ample quantities to <br />neutralize the acid forming component in the coal. Therefore, the acid produced <br />would react with the lime to produce gypsum, water and carbon dioxide. In <br />addition, some soluble sulfates may be formed upon reaction with other base <br />minerals. The reaction is: <br />H2S0, + CaCO, ---> CaSO, + H2O + CO2 <br />PR-08 <br />~PPROvEQ <br />y~z5~03 <br />2-04-17- <br />7/03 <br />