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8.1. Excavation of trenches and bulk excavation and placement of fill may be accomplished by any method and by use of any excavation and hauling equipment suitable for the work and site conditions. Unsuitable equipment and equipment in disrepair or unable to pertorm the intended tasks shall not be mobilized to the work site or used in the pertormance of the work. 8.2. All excavations shall be performed to neat lines and grades as indicated on the Drawing, as specified herein or as designated by the Engineer. Any over excavation or excess excavation not requested or authorized by the Engineer shall be at the expense of the Contractor. 8.3.It is the responsibility of the Contractor to maintain the required layback slope of structural or trench excavations to meet applicable MSHA and/or OSHA safety requirements. 9. HANDLING AND PLACEMENT OF EARTH MATERIAL 9.1. GENERAL 9.1.1. Earth materials shall be handled, transported and stockpiled in such a manner as to prevent any undesirable segregation of or intermixing of various types of earth materials. 9.1.2. Earth materials shall be placed in near horizontal layers to the specified lift thickness. Distribution and gradation of materials throughout the layers shall be such that the placed materials shall be free from segregated lenses, pockets, streaks or layers of materials differing in texture or gradation from surrounding material. 9.1.3. Successive loads of earth materials shall be dumped so as to provide the best practical distribution of material. 9.1.4. If the surface of any layer of rolled fill is too dry or too smooth to bond properly with the layer of material to be placed thereon or has formed a hard compacted crust from traffic, it shall be moistened to optimum moisture and scarified as required before the succeeding layer of material is placed. 9.1.5. The removal of wet or soft materials shall be carried to such depth as determined by the Engineer to expose firm materials. The exposed surface shall be scarified or lightly disked in order to provide an adequate bond for the subsequent layer of fill. 9.1.6. At abutments and/or against previously placed fill, each lift shall be benched into the existing slope to provide a suitable bond between existing and new materials. 9.1.7. The in-situ moisture content of the material in borrow areas may be greater than +2 percent over optimum. If the moisture content exceeds this allowable limit and no alternative source of suitably dry material can be found, the Contractor shall take the appropriate measures to dry the fill material before placing, including but not limited to: (a) excavating and spreading the material to dry, followed by actual placement; and/or (b) mixing with drier materials to obtain the required moisture content. 9.1.8. No earth material shall be placed underwater, in a frozen condition, or upon frozen soils. 9.1.9. The Contractor shall utilize suitable equipment to achieve the compaction required by this specifica- tion. 9.2. COMMON FILL 9.2.1. Common fill that is not a part of a roadway shall be placed in horizontal loose lifts and compacted to a minimum of 90 percent of the maximum Standard Proctor density (or as designated on the Drawings) as determined in accordance with ASTM D 698. The loose lift thickness before compaction shall not exceed 12 inches. 9.2.2. The in-place moisture content of common fill shall be within -2 percent and +2 percent of the optimum. To assure maximum consistency, water, as required, should be added to the materials at the borrow area. 9.3. SELECT FILL, CULVERT BACKFILL, AND SUBGRADE FILL BELOW ROADWAY PAVEMENT 9.3.1. Select fill shall be placed in horizontal loose lifts and compacted to a minimum of 95 percent of the maximum Standard Proctor density as determined in accordance with ASTM D 698. The loose lift thick- ness before compaction shall not exceed 12 inches for areas amenable to the use of large compaction SPECIFICATION A EARTHWORK PAGE 6