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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 <br />Yoast Mine permit application stated: <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 <br />above the coal seam. Typical overburden handling will effectively bury much <br />of these strata in the central portion of the spoil profile. However, based upon <br />previous information from the adjacent Seneca II Mine, acid mine spoil may <br />occasionally be identified at the surface of final graded spoil. These areas, <br />identified by the regraded spoil monitoring program, will be buried with a <br />minimum of three feet 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 <br />deposited at the surface of the graded spoils. The Division concurs with these <br />determinations, and finds the regraded spoil sampling and mitigation plan as <br />referenced on page 40, Tab 6, to be warranted and appropriate. The sampling plan <br />was applied to all regraded spoil areas and graded final highwalls in the south <br />extension mining block (both Wadge and Wolf Creek/Sage Creek mining areas). As <br />previously mentioned, the monitoring conducted during reclamation indicated all <br />spoil materials sampled were suitable. <br />Summary Findings <br />Pursuant to 4.05.8(3), temporary storage of acid or toxic forming spoil may exceed <br />30 days if the operator demonstrates that burial or treatment is not feasible within 30 <br />days due to weather conditions or other specified factors, and will not result in <br />material risk of water pollution or other environmental damage. If deemed <br />necessary by the Division based on the quantity, location, and chemical <br />characteristics of any temporarily stored acid - forming or toxic - forming spoil, such <br />spoil shall be placed on 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 />indicated excessive clay content. Such high clay areas are ripped during regrading <br />operations to relieve compaction. No indication of the presence of acid forming or <br />Seneca II -W Findings Document 25 C- 1982 -057 <br />Permit Revision No. 6 January 6, 2012 <br />