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Wolf Creek/Sage Creek Overburden/ilnderburden Assessment Only two parameters (iron and lead) exhibited unsuitable levels within sampled increments from the one bore hole that penetrated the sequence in the south extension area. Within each of four delineated intervals (Sage Creek overburden, Upper Wolf Creek overburden, Lower Wolf Creek overburden, and Wolf Creek underburden), composite samples were taken from each 10 foot depth increment. The average value for lead within the Lower Wolf Creek overburden interval was in the unsuitable range, due to a very high value within one of five sampled increments. One or more sample increments within the Sage Creek and Wolf Creek overburden intervals exhibited unsuitable iron levels, but the average iron level within each interval was suitable. One of six sampled increments in the Upper Wolf Creek overburden was in the unsuitable range for lead, but the average value for the interval was marginally suitable. Concern relative to elevated levels of the two metals aze minimised due to the neutral to slightly basic pH range indicated within each sampled increment, and the resulting low solubility of the metals. Sampling of the Wadge underburden/Sage Creek overburden at the adjacent Yoast Mine permit area identified no unsuitable parameter levels, however a concern was identified regarding potential acidity in the Wolf Creek overburden, particularly in a zone 20 to 35 felt above the coal seam. Specifically, narrative in Tab 21 of the Yoast Mine permit application stated: Excessive ABP -(Acid-Base Potential) levels were identified in 28.9 percent of the Wolf Creek overburden at Site 2313E, mostly in the 20 to 35-foot zone above the coal seam. Typical overburden handling will effectively bury much of this strata in the central portion of the spoil profile. However, based upon previous information from the adjacent Seneca II Mine, acid mine spoil may occasionally be identified at [he surface of final graded spoil. These areas, identi£ed by the regraded spoil monitoring program, will 6e buried with a minimum of three feet of suitable spoil prior to soil replacement. Narrative on page 39, Tab 6 states, based on the sampling results described and the proposed sequence of mining and reclamation operations, that unsuitable surface conditions aze expected to be avoided by dilution of burial. However, the narrative further acknowledges the potential that areas of unsuitable material could be deposited at the surface of the graded spoils. The Division concurs with these determinations, and fords the regraded spoil sampling and mitigation plan as referenced on page 40, Tab 6, to be warranted and appropriate. The sampling plan will be applied to all regraded Seneca R-W Findings Document 28 November 17, 2004 Perini[ Revision No. 4