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Seneca Coal Company July 2010 <br />Seneca II-W Mine <br />SL-3 - Phase I Bond Release Request <br />• <br />• <br /> <br />remediated over the past years, however; no major instances of instability have been identified in <br />the area requested for Phase I bond release. <br />Postmine drainage channels were designed and constructed to control runoff and erosion. All of <br />these channels were designed and constructed to control, at least the 10-year, 24-hour storm <br />event. In most cases where grades are steep, the riprap used to control erosion and flow <br />velocities is at least 3 inches larger in diameter than the design specifies. This conservatism used <br />in the construction helps to ensure stability of the channels. During the later phases of <br />permanent channel construction the use of riprap in the channels was replaced with TRM (turf <br />re-enforcement material). The locations of the postmine channels are shown on the attached <br />Exhibit B, Postmine Topography and Drainage Map, while the as-built profiles for these <br />channels are presented on Exhibit D, As-Built Drainage Profiles. These postmine drainage <br />channels all ultimately flow to National Pollution Elimination Discharge System (NPDES) <br />discharge points to ensure that water quality leaving the permit area is within regulatory <br />specified limits. <br />The CDRMS completed a review and evaluation of the initial SL-2 Phase I bond release <br />application in May 2010 and approved release of 721.9 acres. The evaluation concluded that <br />specific areas, at the time of the bond release inspection, did not meet all criteria to allow bond <br />release; therefore these areas were excluded from the area approved in the SL-2 for bond release. <br />SCC had submitted the SL-2 application prior to numerous intense storm events in 2009. Based <br />on the extent of erosion damage and on-going remedial work in the South Extension Area, the <br />CDRMS and SCC agreed that it would be premature to grant Phase I bond release for the South <br />Extension Area. For this reason, 399.5 acres in the South Extension area was excluded from the <br />SL-2 review and evaluation. <br />The following table presents the CDRMS excluded areas and acreages along with SCC's <br />surveyed acreages for each exclusion area. This acreage comparison is necessary to reconcile <br />total acres for future bond release requests and annual reports. Some of these excluded areas are <br />included in this SL-3 bond release request package. <br />Description <br />South Extension Area <br />A Pit Highwall Slump <br />Channel 006-NE2 <br />Channel 006-E1 (006 Gulch) <br />Light Use Road LU-IA <br />Light Use Road LU-1 <br />Light Use Road LU-3 and 4 <br />Oil Well Road <br />Road "J" <br />Culvert I-1 area <br />Scraper Road Exclusion <br />SL-2 EXCLUSION AREAS <br />CDRMS Acreage <br />402.85 <br />10.00 <br />0.23 <br />0.36 <br />0.20 <br />0.83 <br />2.35 <br />0.93 <br />0.94 <br />0.03 <br />12.10 <br />SCC Surveyed Acreage <br />399.50 <br />9.42 <br />0.23 <br />0.36 <br />0.20 <br />0.83 <br />2.35 <br />0.95 <br />0.69 <br />0.03 <br />12.10 <br />Total <br />430.89 <br />426.66 <br />SL-3 -4