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Seneca Coal Company, LLC <br />Seneca II-W Mine April 2009 <br />Phase I Bond Release Request <br />Exhibit C, Typical Cross Sections of Backfilled and Graded Area, provides representative cross- <br />sections showing the final topographic configuration. A more detailed discussion of the overall <br />mining and reclamation can be found in the Seneca II-W Mine Permit Application, specifically Tab <br />12, Operation Plan and Tab 20, Backfilling and Grading. Rill and gully surveys are conducted <br />annually in the spring of each year to identify areas that have experienced erosion or other signs of <br />instability during spring runoff from snowmelt and precipitation events. Varying degrees of rills, <br />gullies and slumps have occurred and been remediated over the past years, however; no major <br />instances of instability have been identified in 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 event. <br />In most cases where grades are steep, the riprap used to control erosion and flow velocities is at least <br />3 inches larger in diameter than the design specifies. This conservatism used in the construction <br />helps to ensure stability of the channels. During the later phases of permanent channel <br />construction riprapped channels were replaced with TRM (turf re-enforcement material) lined <br />channels. The locations of these channels are shown on the attached Exhibit B, Post Mining <br />Topography Map, while the as-built profiles for these channels are presented on Exhibit D, As-Built <br />Drainage Profiles. These postmine drainage channels all ultimately flow to National Pollution <br />Elimination Discharge System (NPDES) discharge points to ensure that water quality leaving the <br />permit area is within regulatory specified limits. <br />PHASE I EXHIBIT DESCRIPTIONS <br />The following list describes the accompanying maps included in this package to provide further <br />documentation and support for this Phase I portion of the bond release request. <br />• Exhibit A, Phase I Bond Release Areas, shows the location of the 1,152.6 acres included in <br />the Phase I portion of this request. <br />• Exhibit B, Post Mining Topography Map, shows final post-mining topography for all Seneca <br />II-W Mine lands regraded through 2008. Also included are the locations of permanent roads, <br />postmine channels, existing stock ponds and sediment ponds. <br />• Exhibit C, Typical Cross Sections of Phase I Bond Release Area, presents representative <br />cross-sections showing final topographic configuration. There are differences in elevation, at the <br />disturbance boundary, between pre- and postmine configurations. This difference is attributed <br />to upgraded technology and survey control over the past decade between aerial photography and <br />on-the-ground surveying. <br />• Exhibit D, As-Built Drainage Profiles, shows the longitudinal profile and grades of each <br />permanent drainage channel. These profiles demonstrate that drainages have been reestablished <br />to provide stable channels according to the approved permit design. <br />ATTACHMENT DESCRIPTIONS <br />• Attachment A, Notarized Statement - contains a Notarized Statement stating that all <br />reclamation work has been completed in compliance with approved permit and Rule <br />3.032(l)(e). <br />4