1998-06-19_GENERAL DOCUMENTS - C1981017

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project, the side slopes of the nibble will not exceed 5H:1 V on the north facing slope, 4H.1 V on the east facing slope, and 3H:1 V on the west facing slope. It is anticipated that the area of the disposal site, including side slopes, will be approximately two and one half (2.5) acres. In order to accommodate the volume of coal refuse expected to be generated during excavation of the north slope of the Old Refuse Pile, it is anticipated that an average depth of twelve feet(12') of coal refuse will be placed over the entire disposal facility. When disposing of the coal refuse at the disposal facility, certain construction requirements will be implemented. Coal Refuse Disposal Requirements (1) Coal refuse materials will be placed in horizontal lifts no greater than twelve inches in thickness. Placement will begin around the perimeter of the concrete ";posal facility, and proceed toward the crest of the rubble, then across the top of une concrete rubble. (2) Each lift will be thoroughly compacted by a non-vibrating sheeps foot roller prior to beginning placement of the succeeding layer. Optimal compaction of the material is ninety percent(90%) of maximum dry density. (3) In order to achieve the optimal dry density during compaction, it may be necessary to add water to refuse which appears dry during lift construction. (4) In no instance shall the outslope formed during construction of fills be steeper than 3H:1 V. The slope gradients created during placement of the coal refuse shall not exceed the slope gradients created by the concrete rubble. (5) Dependent upon conditions, it may be necessary to construct one or more under drains near the base of the disposal facility. The purpose of the drains is to allow ground water which may be present at the fill area(s) to drain from the fill without saturating the coal refuse material. A typical drain dimension is shown in Figure 1, Under Drain. Note that the drain length is unknown, and that the cross- sectional area may vary based upon site conditions. PROJECT MANAGER will make such determination prior to CONTRACTOR initiating fill operations. Under Drains, if constructed, will be built to the specifications described in Task 7, Under Drains. These features will be paid per the price bid in Item 7 of the Bid Schedule per lineal foot installed. Site and material conditions are such that extremely dusty conditions may result from the excavation, hauling and deposition of coal refuse. Hauling, dumping and spreading of topsoil materials may result in similar conditions. PROJECT MANAGER may require CONTRACTOR to implement dust control procedures throughout the Project Area for the duration of the Project. Such practices, such as applying water to work areas and roadways, are considered to be normal construction practices, and shall not result in additional expense to OWNER. 10