Laserfiche WebLink
Backfill and grading deadlines for the timeframe variance areas approved in PR-5 <br />are set forth on pages 5-7 of Tab 19 of the permit application, and depicted on the <br />amended Exhibit 19-1 "Bachill and Grading Plan" certified January 13, 2006. <br />The Division approves a variance from the 180 day rough backfilling and grading <br />requirement of Rule 4.14.1(1)(c), for the variartce areas delineated on Exhibit 19- <br />1, and described as: <br />• 1,600 feet of the "A" Pit Ridgeline Pit; backfilling/grading to be <br />completed by the end of 2005. <br />• 2,800 feet of the Wadge Pit Northern Area; bacl-£illing/grading to be <br />completed by the end of 2005. <br />• 900 feet of the Wadge Pit Central Area to be backfilled/graded by the end <br />of 2005. <br />• 700 feet of the Wadge Fit Central Area to be backfilled/graded by the end <br />of 2006. <br />• 1,400 feet of the Wadge Pit South Area to be backfilled/graded by the <br />end of 2005. <br />• Approximately 15 acres of the Wolf Creek area to be backfilled/graded by <br />the end of 2006. <br />As of June 2006, rough grading has been completed in all of the variance areas <br />with 2005 completion deadlines. Grading remains to be completed in the Wadge <br />Pit Central Area and Wolf Creek variance areas, with 2006 completion deadlines. <br />Potentially acid or toxic-forming spoil material has been and will be identified by <br />sampling regraded spoil, and will be chemically treated or buried with a minimum of <br />four feet of topsoil. By neutralizing and/or isolating any acid or toxic-forming material <br />from the surface, and mixing limited quantities of such material with much greater <br />volumes of alkaline and benign spoil material, any negative effects of problematic <br />material will be ameliorated. <br />The Division approves this method for covering acid and toxic forming materials in <br />order to prevent leaching into surface and ground water and to insure backfill stability. <br />(4.14.3(2)). <br />A large slump that occurred along the southern highwall of the "A" Pit following <br />backfilling, and prior to topsoiling, focused attention on stability of similar steep <br />slope locations in the South Extension Area. The "A" Pit slump area was <br />properly repaired by slope reduction grading, and was subsequently topsoiled and <br />___ revegetated in 2004. [n association, with PR-5, slope stability analyses were <br />completed, to ensure that proposed grading procedures and final slope gradients in <br />the South Extension area would result in postmine slopes with minimum static <br />safety factor of 1.3, as required by Rule 4.14.2(1)(b). The evaluation results are <br />Seneca II-W Findings Document 55 June l2, 2006 <br />Permit Renewal No. 5 <br />