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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 the <br />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 stated: <br />Excessive ABP (Acid-Base Potential) levels were identified in 28.9 percent of the <br />Wolf Creek overburden at Site 2313E, mostly in the 20 to 35 foot zone above the <br />coal seam. Typical overburden handling will effectively bury much of this strata <br />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 of final 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 />conditions are expected to be avoided by dilution or burial. However, the narrative <br />further acknowledges the potential that areas of unsuitable material could be deposited <br />at the surface of the graded spoils. The Division concurs with these determinations, <br />and finds the regraded spoil sampling and mitigation plan as referenced on page 40, <br />Tab 6, to be warranted and appropriate. The sampling plan was applied to all regraded <br />spoil areas and graded final highwalls in the south extension mining block (both <br />Wadge and Wolf Creek/Sage Creek mining areas). As previously mentioned, the <br />monitoring conducted during reclamation indicated all spoil materials sampled were <br />suitable. <br />Summary Findings <br />Pursuant to 4.05.8(3), temporary storage of acid or toxic forming spoil may exceed 30 <br />days if the operator demonstrates that burial or treatment is not feasible within 30 days <br />due to weather conditions or other specified factors, and will not result in material risk <br />of water pollution or other environmental damage. If deemed necessary by the <br />Division based on the quantity, location, and chemical characteristics of any <br />temporarily stored acid-forming or toxic-forming spoil, such spoil shall be placed on <br />impermeable material. <br />Based on data included in annual reclamation reports, spoils exhibiting acid or toxic <br />forming potential or other chemical unsuitability, have not been replaced on the <br />surface. A very low percentage of samples (primarily final highwall locations) have <br />Seneca II-W Findings Document 27 C1982057 <br />Permit Renewal No. 5 December 9, 2010