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the Wolf Creek reclamation area. Mn levels greater than 60 and 70 ppm have not been encountered since 1987 and 1984, respectively. The mean extractable Mn values in the mixed spoil and selectively handled spoil topdressing decreased 65 percent during the 1988-1989 period compared to the 1983-1987 period. Lastly, the regraded spoil sampling is now 500 feet and 1,400 feet south of premine overburden sample sites 2434E and 2438E (see Seneca II PAP, Tab 6, Exhibit 6-1, Drill Hole Location Map), respectively, where the original Mn concern was identified and where spoil Mn sampling and analysis was to occur (see Seneca II PAP, Tab 6, page 6-153). Wadge Mining and Reclamation Area _ ~~ ~ Peabody is required to monitor nitrate levels d~Spring B~O~ d bpg -00 and in spoil col e7 cted-from representative-revegetation sites as out~d in the Third Annual Topsoil and Spoil Monitoring Report (1988 ~~ field season) and on pages 6-153a and 6-164 of Tab 6 in the Seneca II PAP. All of the nitrate data is contained in the First and Third Annual Topsoil and Spoil Monitoring Reports. The active mining and spoil grading operations are currently located at least 2,500 feet north of sites 2034E, 2613E, and 2614E (see Seneca II ,~v PAP, Tab 6, Exhibit 6-1, Drill Hole Location Map) where the original O premine overburden nitrate concerns were identified. Correspondingly, mean annual nitrate values have decreased considerably since 1986 in Spring BP-0001 and Pond DA-0004 as the mining activities moved further north from these monitoring sites. The mean nitrate values at sites BP-0001 and DA-0004 have decreased 90 and 70 percent, respectively during the 1987-1988 period compared to the 1983-1986 period. Twenty-nine water samples have been collected from Spring BP-0001 and Pond DA-0004 and analyzed for nitrate. The nitrate values ranged from 0.02 to 13.8 ppm with only one sample, collected in 1983, exceeding the domestic drinking water standard of 10 ppm established by the U.S. EPA (1976) and the Colorado Department of Health (1977). The mean nitrate value in the spring and pond from 1983 through 1988 was 3.17 ppm. The nitrate concentration was also determined on 19 spoil samples collected from 11 representative revegetation sites during the 1986 and 1988 field seasons. The mean nitrate concentration for the Wadge spoil was 1.4 ppm with a standard deviation of 0.9 ppm. This nitrate concentration is more than an order of magnitude below the ground water contamination level of 60 ppm (Nucla Mine PAP, Tab 6, Attachment 6-1, Table 6-1-3) and actually approaches the plant deficiency level of 2 ppm (Third Annual Topsoil and Spoil Monitoring Report, Table 3). No revegetation toxicity or ground water nitrate contamination problems are evident from the monitoring data collected in the Wadge mining area since 1984. The nitrate concentration from 1987-1988 at Spring BP-0001 and Pond DA-0004 are 90 and 70 percent, respectively, less than the values recorded during 1983-1986. Spoil nitrate values actually approach plant deficiency levels.