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• 2.04.6 <br />In oxidizing conditions at pH > 4.0, ferric oxide will <br />form. At pH < 4.0 under oxidizing conditions, a mineral <br />called jarosite will form. Jarosite is very insoluble <br />and is not a concern. A common iron mineral, goethite, <br />will form in small amounts across the common pH spectrum <br />under slightly oxidizing conditions. <br />If the acid produced under complete oxidation is not <br />buffered by the surrounding mineral matrix, about 625 <br />pounds of Calcium Carbonate (lime, CaCOI) would be <br />required to neutralize 1,000 tons of material bearing <br />0.018 iron pyrite such as in DH-12. <br />A sample of run of mine coal, from the nearby Bowie No. <br />1 Mine D-Seam, was analyzed to determine if the D-Seam <br />coal in the area has sufficient lime to neutralize its <br />acid producing characteristics. The D-Seam coal has a <br />carbonate equivalent of 0.228 which equates to 4.4 pounds <br />per ton of coal or 4,400 pounds of lime per 1,000 tons of <br />coal. This means the coal contains adequate lime to <br />• neutralize coal bearing 0.078 iron pyrite (4,400 + 625). <br />The laboratory report is presented in Volume III, Exhibit <br />6. <br />Other evidence the area D-Seam coal does not have acid <br />producing characteristics is the old Oliver Mine No. 1 <br />located east of Somerset, CO which mined in the D-Seam in <br />the 1940's and 1950's. This mine is discharging water <br />that is monitored by Oxbow Carbon & Minerals as spring 8. <br />This "spring" water consistently has a pH in excess of <br />7.0 (ref. OCM 1994 Annual Hydrologic Report). <br />Based on the above discussion, it is likely lime is <br />present in ample quantities to neutralize the acid <br />forming component in the coal. Therefore, the acid <br />produced would react with the lime to produce gypsum, <br />water and carbon dioxide. In addition, some soluble <br />sulfates may be formed upon reaction with other base <br />minerals. The reaction is: <br />H~SO~ + CaCO~ ---> CaSO~ + H=0 + CO= <br />• P6PMITAPPLIGTIOP 2-04 - 16 - <br />