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and/or bury the unsuitable day strata. Typical overburden handling operations are described in Tab 12, Coal <br />• Resource Recovery Plan and Tab 20, Backfilling and Grading. <br />Unsuitable clay strata comprise 18.6 to 52.4 percent of the overburden section at Skes 43-C, 99-C, 508-C, <br />1128-E, and 1130-E. The excessive Gay values are associated with the shaley overburden strata that <br />ovedies the Lennox coal seam. Because these elevated Gay levels are found in the upper half of the <br />overburden section, SCC anticipates the material will be buried by typical overburden handling operations <br />and will occupy the central portion of the backfilied spoil profile. Cast blasting will be used to fracture the <br />consolidated overburden. During cast blasting, part of the lower half of the overburden consisting <br />predominantly of hard sandstone, will likety be projected into the adjacent pit. The shaley overburden will <br />then be uncovered by the dragline and placed over the sandstone rubble. Lastty, the shaley spoil will be <br />covered by the remaining fractured sandstone. <br />Typical overburden handling will be used to blend, dilute, or bury strata with unsuitable nitrate levels. <br />Blending and dilution will be effective at Sites 1127-E, 1129-E, and 1130-E where unsuitable nitrate strata <br />comprise 13.8, 4.2, and 7.2 percent, respectively, of the overburden section. Excessive nitrate levels were <br />identified in 45 percent of the overburden at Site 1128-E, mostly in the upper 65 feet. Typical overburden <br />handling will effectively bury this strata in the central portion of the spoil profile. SCC also believes that <br />sampling error (improper sample handling or sample contamination from drilling adddives) may have <br />contributed to the excessive nitrate levels identified in the 1981 overburden cores. Nitrate contamination <br />• problems were also identified for three overburden cores that were collected in August and September 1981 <br />from the Seneca II Mine (Peabody Coal Company, 1986). <br />Typical overburden handling will be used to blend, dilute, or bury strata with unsuitable manganese levels. <br />Blending or dilution will be effective at Site 1128-E where unsuitable manganese strata comprised 5.1 <br />percent of the overburden section. Excessive manganese levels were identified in 30 percent of the <br />overburden at Site 1127-E, mostly in the upper 13 feet. Typical handling will efredively bury this strata in the <br />central portion of the spoil profile. Like most trace elements, manganese is fairly insoluble over a pH of 6.0. <br />Manganese stability is expelled in the spoil pile because of the neutrel reaction and excess carbonates. <br />Regraded Spoil Monitoring Program. In order to provide a feedback system to check the reliability of the <br />overburden sampling and analysis program, a regraded spoil monitoring program will be initiated. A <br />sampling plan, consisting of a 60 degree slant grid system on 500-foot centers, will be continued on all <br />graded spoil and reduced highwall areas to determine spoil/subsoil suitability prior to topsoil <br />replacement <br />r <br />LJ <br />TR-50 3 Revised 10/05 <br />