1996-06-30_GENERAL DOCUMENTS - C1981017

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The remaining Lower Bench remnant shall be graded to ensure that water drains away from the base of the fill area. Three (3) contour furrows two feet wide and eighteen (18) inches deep will be constructed on the bench remnant to minimize the transport of sediment from the reclaimed area. These furrows are described, and will be constructed and paid for, under Task 5, Surface Drainage. Upon completion of backfilling, grading and drainage construction, the bench remnant shall be ripped to a depth of eighteen (18) inches. Measurement and Payment There will be no measurement for payment for excavation, placement of backfill materials, grading and ripping. Payment for these portions of Task 4 will be reflected in a lump sum bid under Items 4a and 4b on the Bid Schedule. This lump sum bid will cover all costs for excavation and placement of the bench outslope materials, placement and compaction of the fill at the base of the highwalls, final grading of the bench, cut and fill area outslopes, and ripping of each area. Payment shall be as this task is completed and approved by the PROJECT MANAGER. TASK 5 SURFACE DRAINAGE Task 5 involves constructing furrows at the Mine 4 Bench (Task 5a) and at the Lower Bench Area (Task 5b). Task 5a - Mine 4 Bench Task 5a includes five (5) contour furrows which will be constructed at the Mine 4 Bench remnant after backfilling of the highwall is completed. The furrows will be trapezoidal in shape, with a bottom width of (2) feet. Each furrow will be a minimum of eighteen (18) inches deep as measured from the base of the furrow to its crest. Side slopes will be no steeper than 21-1:1 V (Cross Section 1 , Generalized Cross Section of Furrows). The locations of the furrows will be staked in the field by the PROJECT MANAGER prior to construction. Approximately 2,600 lineal feet of furrows will be constructed at the Mine 4 Bench Area. Task 5b - Mine 4 Lower Bench Area Task 5b includes two (2) contour furrows which will be constructed at the Mine 4 Lower Bench Area after backfilling of the highwall is completed. The furrows will be trapezoidal in shape, with a bottom width of (2) feet. Each furrow will be a minimum of eighteen (18) inches deep as measured from the base of the furrow to its crest. Side slopes will be no steeper than 2H:1 V. The locations of the furrows will be staked in the field by the PROJECT MANAGER prior to construction. Approximately 700 lineal feet of furrows will be constructed at the Mine 4 Lower Bench Area. 10