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separated within reasonable capabilities of the equipment for selective replacement during reclamation. 6.6. Materials not suitable for reuse, such as debris, waste material, and metals shall be disposed of at a location to be designated by the Engineer. No topsoil or soils containing organic materials shall be wasted, buried or otherwise disposed of unless approved by the Engineer. 7. FOUNDATION PREPARATION 7.1. CULVERTS 7.1.1. Excavation or fill shall proceed to at least six inches below the level of the culvert invert and the Contractor shall proof roll the foundation material to determine its competency. If the foundation material is suitable at that depth, placement of the culvert bedding material may begin with this surtace. 7.1.2. If the foundation soils are unsuitable because of over-wet condition, presence of peat or muck, or apparent lack of consolidation for significant depth, the foundation shall be overexcavated by at least 12 inches and the over-excavation shall be filled and compacted with foundation gravel or select fill to 95 percent Standard Proctor Density within 2 percent optimum moisture up to the specified foundation grade. 7.2. FOUNDATIONS FOR RIPRAP AND RIPRAP BEDDING 7.2.1. For riprap and riprap bedding foundations; excavation or fill shall proceed to the level of the finish grade less the required thickness of the riprap and bedding, and the Contractor shall proof roll the foundation material to determine its competency. If the foundation material is suitable at that depth, placement of the riprap or riprap bedding material may begin with this surtace. 7.2.2. If the foundation soils are unsuitable because of over-wet condition, presence of peat or muck, or apparent lack of consolidation for significant depth, the foundation shall be overexcavated by at least 12 inches and the over-excavation shall be filled and compacted with foundation gravel or select fill to 95 percent Standard Proctor Density within 2 percent optimum moisture up to the specified foundation grade. 7.3. SUBGRADE PREPARATION FOR ROAD PAVEMENT AND CUT/FILL 7.3.1. Areas that have been stripped of topsoil and are to receive fill material shall be proof rolled with a heavily loaded pneumatic-tired vehicle. In areas that deform excessively under the heavy wheel load and are within two feet of the base of the Aggregate Base Course layer the soils shall be removed to a depth of three feet below the base of the Aggregate Base Course layer and replaced with non-plastic, granular common fill soils. 7.3.2. If the subgrade is excessively wet the soils shall be excavated and replaced with a drain field composed of cobble sized rock and Geotextile, as shown on the drawings. 7.3.3. If the roadway subgrade has been cut to grade the subgrade area shall be scarified to a depth of 12- inches after the subgrade elevation has been attained, the subgrade soils adjusted to a moisture content within 2 percent of optimum and the subgrade compacted to at least 95 percent of the standard Proctor Density. 7.3.4. If the roadway subgrade has been filled to attain the grade, the moisture content of the last 8-inches (loose) of fill shall be adjusted to within 2 percent of optimum and compacted to at least 95 percent of the standard Proctor Density (ASTM D698). 7.3.5. After preparation of the subgrade as described above, the subgrade shall again be proof-rolled with a heavily loaded, pneumatic tired vehicle. Areas that deform excessively under heavy wheel loads shall be removed and replaced with non-plastic or low plasticity, granular material prior to placing the Aggregate Base Course Material. 7.3.6. If areas are encountered where soft subgrade soils are occur at depths exceeding three feet, the Engineer may require additional Aggregate Base Course thickness, or additional Geogrid layers, or both. 8. GENERAL PROCEDURES SPECIFICATION A EARTHWORK PAGES