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nevtralizaYron of 1,000 tons of host rock (10007). Positive ABP's indicate that the host material, when saturated with fluid of a near-neutral pH, will produce an alkaline solution. Negative ABP's indicate that the resulting solution will be acidic. Table 17-33, Acid Base Potential of Overburden Cores, Seneca II-W South Area, presents an ABP summary for overburden core samples collected within the South expansion area. None of the cores show overall acid potentials, due to the high percentage of CaCO3 in each core. Mean weighted acid potentials for the Wadge overburden cores vary from 1.0 to 19.5TCaCO3/10007; mean weighted neutralization potentials vary from 51.0 to 80.9 TCaCOa/10007. The Sage Creek/Wolf Creek overburden values presented in Table 17-33 are based on samples collected from one locale down dip of the proposed mining area. The average acid potentials for the Sage CreeklWolf Creek overburden vary from 9.8 to 22.4 TCaCO3/10007, while the average neutralization potentials vary from 48.4 to 112.5 TCaCO311000T. These data suggest that the overburden sediments in the South mining area, when acting as infiltrating media, will generate neutral to alkaline solutions and have the capacity to buffer acidic, infiltrating solutions. Additional information is included in Tab 6. The paste pH value of a material is another indicator of the potential of the material to generate acidic fluid. Paste pH values for core samples from both the Seneca II-W and Seneca II-W South areas were also analyzed. Table 17-34, Summary of Seneca II-W and Seneca 11-W South Overburden Core Paste pH Values, presents summaries of acidic, core paste pH values li.e., average core pH values of less than seven standard units) for the Seneca II-W and Seneca II-W South areas. Seven of the Seneca II-W cores include samples from the Lennox coal, and all of the acidic portions of the cores were associated with the Lennox Unit and the immediately overlying and underlying shales. Approximately 14.2 percent of the total core length collected from the Seneca II-W area contains pH values less than neutral, and a majority of the core samples with acidic pH values fall within the range of 6.0 to 7,0 standard units (versus less than 6,0 standard units). Paste pH values from the Seneca II-W South area range from 6.4 to 8.3 standard units. Only 10,6 percent of the total core length collected from the Seneca II-W South area contains acidic paste pH values, and most of these paste pH values are only slightly acidic, or near neutral. Because the percentage of all core from the South expansion area with acidic material is minimal, and the ABP accounting indicates that the associated overburden material exhibits a high neutralization potential, the resultant spoil water in the Seneca II-W South area land Seneca II-W areal is not expected to have a pH value of less than 7.0 standard units, and thus is not expected to act as a leaching solution. 100 Revised 1/02