1997-06-18_GENERAL DOCUMENTS - C1981017

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The lower portion of the conveyor transfer building contains a coal conveyance tunnel with a concrete covered return tunnel within it. The small return tunnel must be demolished from its terminus to the point at which it is parallel with the face of the larger tunnel. Demolition of the larger tunnel inby its face is not required. However, demolition and complete removal of all concrete and metallic materials beyond the face of the tunnel is required. Other than conveyor transfer tunnel, all concrete foundations at the transfer building must be completely excavated, demolished and removed. Some of the demolished materials (rubble) will be stowed within the upper and lower tunnels located in the vicinity. The two tunnels (upper and lower) must be filled with rubble for a minimum distance of twenty feet (201) starting five feet (5') inside the tunnel entrances. The rubble shall be stowed in the tunnels so that it extends the entire twenty feet (20') distance and from top to bottom and side to side. The outside-most five feet (5') will be filled with earthen materials as described in Task 4, Earth Work. The water tank foundation and all concrete materials, other than the tunnels themselves, must be completely excavated. Rubble not disposed of in the tunnels will be removed to the Wash Plant disposal area (see Eastern Work Area and Map 4, Project Area). Eastern Work Area The facilities to be disposed of at the eastern work area in the Warehouse Vicinity are mainly concrete and asphalt pads which previously supported warehouse buildings, parking areas and roads. A number of conveyor related foundations are located along the northern perimeter of the area. Some of the foundations are buried under coal fines and soil along the route of the conveyance system in this area. All concrete, asphalt pads, cinder block buildings and similar materials located within the eastern area must be completely excavated and removed from this area to the Wash Plant disposal area. No remnants of buildings, foundations, pads or roadways may be left at this work area. The demolished concrete, cinder block, asphalt and metallic materials excavated from the eastern portion of the warehouse area and from the western area, if any, will be disposed of at the toe of the back wall cut behind the former Wash Plant (see Map 4, Project Area). The disposal area limits will be marked in the field by the PROJECT MANAGER prior to disposal being initiated. Caution must be exercised when transporting materials to the disposal location, as other crews and heavy equipment may be working in the vicinity of the disposal area or along the transportation route. CONTRACTOR is responsible for maintaining a safe work place during performance of this project. Measurement and Payment There will be no measurement for payment. Payment for this task will be reflected in a lump sum bid under Item 2 on the Bid Schedule. This lump sum bid will cover all costs for structural demolition and removal of rubble and debris from each work area, described above, to the disposal areas. Payment shall be as this task is completed and approved by the PROJECT MANAGER. TASK 3 SILT FENCE Silt fences (sediment containment fences) will be installed as per manufacturers specifications (Figure 1, Typical Silt Fence Installation) at various locations to minimize the transportation of sediment from each construction area. Placement of silt fencing will occur at locations specified by the PROJECT MANAGER, generally immediately following excavation and grading operations. The CONTRACTOR will supply the prefabricated silt fence with posts (Mirafi Prefabricated Silt Fence with Posts having a 3 foot width and 8.2 feet between posts, or equivalent). It is estimated that the following lengths of silt 9