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• The elevated iron and manganese concentrations that occur in samples from the Phase I <br />cores ere apparently nonrepresentative. Contamination from drilling greases or additives <br />may have occurred during drilling. The Phase II iron and manganese concentrations were <br />three times less than Phase I. Therefore, the Phase 1 iron and manganese concentrations <br />ere atypically high due [o sample contamination. <br />Ameliorating reclamation techniques and blending, dilution, and/or burial by typical <br />overburden handling will be used to mitigate excessive levels of clay. unsuitable clay <br />percentages comprise less than 75 percent of the overburden section at Sites 2313E, 2314E, <br />2316E, 2318E, 30488, 3049B, 30508, and 30518. Typical overburden handling by cast <br />blasting, dragline spoiling, and dozer grading at these eight sites will effectively <br />blend, dilute, and/or bury the unsuitable clay strata. Typical overburden handling <br />operations are described in tab 12, Coal Resource Recovery Plan and Tab 20, Bac kfilling <br />and Grading. <br />unsuitable clay strata comprise 41.8, 38.5, and 28.1 percent, respectively, of the <br />overburden section at Sites 2309E, 2378E, and 2317E. The excessive clay values are <br />• associated with the sheley overburden strata that overlies the Lennox coal seam. Because <br />these elevated clay levels are found in the upper half of the overburden section, SCC <br />anticipates the material will be buried by typical overburden handling operations and will <br />occupy the central portion of the Dac kfilled spoil profile. Cast blasting will be used to <br />fracture the consolidated overburden. During cast blasting, part of the lower half of the <br />overburden consisting predominantly of hard sandstone, will likely be projected into the <br />adjacent pit. The sheley overburden will then be uncovered by the dragline and placed <br />over the sandstone rubble. Lastly, the shal ey spoil will be covered by the remaining <br />fractured sandstone. <br />Typical overburden handling will be used to blend, dilute, or bury strata with unsuitable <br />acid base potential values. Blending and dilution will be effective at all wedge <br />overburden sites where unsuitable ABP strata comprise less than 6.5 percent of the <br />overburden section. Excessive ABP levels were identified in 28.9 percent of the Wolf <br />Creek overburden at Site 2313E, mostly in the 20 to 35-foot zone above the coal seam. <br />Typical overburden handling will effectively bury much of this strata in the central <br />portion of the spoil profile. However, based upon previous information from the adjacent <br />• Seneca II Mine, acid mine spoil may occasionally be identified at the surface of final <br />graded spoil. These areas, identified by the regraded spoil monitoring program, will be <br />3 <br />