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cover. The regraded areas were sampled during reclamation as required, and all of <br />the samples indicated no mitigation would be required. <br />Nitrate -nitrogen levels were excessive in 14% of the overburden core samples taken <br />at the Seneca II -W Mine. The locations of the holes which exhibited elevated levels <br />were distant from one another. Furthermore, the stratigraphic locations of the <br />elevated nitrate -nitrogen samples are not correlative. Due to the vertical and <br />horizontal distances between locations containing elevated nitrate -nitrogen levels, <br />percolating ground water will not be adversely affected. The dilutional effects of a <br />predicted spoils aquifer should buffer the concentration of nitrate as nitrogen by the <br />time the aquifer discharges to the surface system. <br />Wolf Creek/Sage Creek Overburden/Underburden Assessment <br />Only two parameters (iron and lead) exhibited unsuitable levels within sampled <br />increments from the one bore hole that penetrated the sequence in the south extension <br />area. Within each of four delineated intervals (Sage Creek overburden, Upper Wolf <br />Creek overburden, Lower Wolf Creek overburden, and Wolf Creek underburden), <br />composite samples were taken from each 10 foot depth increment. The average value <br />for lead within the Lower Wolf Creek overburden interval was in the unsuitable <br />range, due to a very high value within one of five sampled increments. One or more <br />sample increments within the Sage Creek and Wolf Creek overburden intervals <br />exhibited unsuitable iron levels, but the average iron level within each interval was <br />suitable. One of six sampled increments in the Upper Wolf Creek overburden was <br />in the unsuitable range for lead, but the average value for the interval was marginally <br />suitable. Concern relative to elevated levels of the two metals are minimized due to <br />the neutral to slightly basic pH range indicated within each sampled increment, and <br />the resulting low solubility of the metals. <br />Sampling of the Wadge underburden/Sage Creek overburden at the adjacent Yoast <br />Mine permit area identified no unsuitable parameter levels; however, a concern was <br />identified regarding potential acidity in the Wolf Creek overburden, particularly in a <br />zone 20 to 35 feet above the coal seam. Specifically, narrative in Tab 21 of the Yoast <br />Mine permit application states: <br />Excessive ABP (Acid -Base Potential) levels were identified in 28.9 percent of <br />the Wolf Creek overburden at Site 2313E, mostly in the 20 to 35 foot zone above <br />the coal seam. Typical overburden handling will effectively bury much of this <br />strata in the central portion of the spoil profile. However, based upon previous <br />information from the adjacent Seneca II Mine, acid mine spoil may occasionally <br />be identified at the surface off nal graded spoil. These areas, identified by the <br />regraded spoil monitoring program, will be buried with a minimum of three feet <br />of suitable spoil prior to soil replacement. <br />Narrative on page 39, Tab 6 states, based on the sampling results described and the <br />proposed sequence of mining and reclamation operations, that unsuitable surface <br />10 <br />