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RESPONSE: <br />The 14 core holes referenced in Tab 6, Table 6-1 on Page 6-15 of Seneca <br />SMP C-80-005 are shown on Exhibit 6-1. The four 1981 core holes listed <br />in Seneca SNP C-80-005, Tab 6, Appendix 6-4, Table 1 (Page 6-139) have <br />been added to the revised Exhibit 6-1 which is enclosed. <br />5. Tab 6 of the original permit application states that overburden <br />with a pH 5.0 or less will be monitored and limed in an attempt to <br />raise the pH. Peabody should discuss this monitoring program <br />addressing how the sampling is done, how the amount of lime to be <br />added is calculated, how the lime will be added, and the final pH <br />of the treated material. <br />RESPONSE: <br />Spoil samples from the Wolf Creek mining area are collected and analyzed <br />as described in adequacy review geology description response Number 2. <br />To date, 49 Wolf Creek mining area samples have been analyzed for pH and <br />ABP. The pH, ASP, and Mn results are presented in Table 1 along with <br />the response to comment Number 2. <br />The most recent data collected in August 1986, depicts normal trends <br />which appear to be occurring in the Wolf Creek mining and reclamation <br />area. Thirteen samples (WC-56 through WC-68) were collected from <br />recently regraded areas prior to topsoil replacement (see Exhibit 9-4, <br />Postmine Topsoil and Spoil Sample Locations). The pH values for these <br />samples ranged from 5 to 7. Consequently, a lime application would not <br />be required in this area based upon the existing permit (C-80-005) <br />condition (Tab 5, Pages 6-30 and 6-33) which requires liming only when <br />pH values are less than 5. However, it must be emphasized that the pH <br />analysis only indicates the intensity of active acidity or alkalinity <br />within the sample. Often, the active acidity level of overburden is <br />very suitable immediately following dragline spoiling, final dozer <br />grading, and topsoiling. However, after a few years of oxidation, <br />weathering, wetting, and drying, the active acidity increases as pyrite <br />sulfur is converted to sulfate sulfur. When the same spoil is measured <br />for pH two or three years later, pH levels may have declined one or two <br /> <br />7 <br />