_GENERAL DOCUMENTS - C1981017 (292)

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Seven (7) contour furrows two (2) feet wide and eighteen (18) inches deep will be constructed on the bench remnant to contain runoff in order to help prevent drainage from flowing both toward the toe of the fill and toward the mine bench outslope. These furrows are described, and will be constructed and paid for, under Task 5, Surface Drainage. Upon completion of backfilling, grading and furrow construction, the bench remnant shall be ripped to a depth of eighteen (18) inches. Task 41b - Mine 3 Intermediate Coal Transfer Area Under Task 4b the Mine 3 Intermediate Coal Transfer Area will receive a similar reclamation treatment as the Mine 3 highwall described above. The unvegetated bench outslopes will be uniformly excavated such that no excavated slope exceeds 2H:1 V upon completion of the excavation. The down slope extent of excavation shall be maintained at as uniform an elevation as possible. The excavated material shall be transported to the base of the highwall and placed over the bench remnant so that the top of the fill extends twenty (20) feet above the base of the bench. The highwall shall be marked in the field by the PROJECT MANAGER at the twenty (20) foot level using paint or other suitable means. Any debris or rubble generated by the conveyor foundation removal described in Task 2, Demolition, which may be disposed of at this location shall be covered by a minimum of four (4) feet of back fill material. The highwall is estimated to be approximately 175 feet in length. The fill shall be compacted in six (6) foot lifts using a sheep's foot roller. The outslope of the fill shall not exceed 21-1:1 V. Four (4) contour furrows two (2) feet wide and eighteen (18) inches deep will be constructed on the bench remnant to contain runoff in order to help prevent drainage from flowing both toward the toe of the fill and toward the Intermediate Bench outslope. These furrows are described, and will be constructed and paid for, under Task 5, Surface Drainage. Upon completion of backfilling, grading and furrow construction, the bench remnant shall be ripped to a depth of eighteen (18) inches. Task 4c - Mine 3 Lower Bench Area Under Task 4c the Mine 3 Lower Bench Area will receive a reclamation treatment similar to that at the Mine 3 highwall described above. The unvegetated lower bench outslopes will be uniformly excavated such that no excavated slope exceeds 2H:1 V upon completion of the excavation. The down slope extent of excavation shall be maintained at as uniform an elevation as possible. The excavated material shall be transported to the base of the highwall and placed on the bench remnant so that the top of the fill extends twenty (20) feet above the highwall bench. The highwall shall be marked in the field by the PROJECT MANAGER at the twenty (20) foot level using paint or other suitable means. Any debris or rubble generated by the conveyor foundation removal described in Task 2, Demolition, which may be disposed of at this location shall be covered by a minimum of four (4) feet of back fill material. The highwall is estimated to be approximately 325 feet in length. The fill shall be compacted in six (6) foot lifts using a sheep's foot roller. The outslope of the fill shall not exceed 21-1:1 V. Four (4) contour furrows two feet wide and eighteen (18) inches deep will be excavated on the lower bench remnant. The purpose of the furrows is to intercept drainage from the Lower Bench and backfill areas in order to minimize sediment transport off site. These furrows are described, and will be constructed and paid for, under Task 5, Surface Drainage. 9