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~~ CIVIL RES"AURCES,LIC Embankment Geometry The project plan is to essentially excavate all the soils on the interior of the site and into bedrock to create the reservoir basin. The reservoir bottom will consist of a graded level bedrock surface, positively graded with a slight slope to the outlet. The slope liner is essentially a homogeneous embankment with the below grade portion constructed of clays primarily derived from claystone bedrock. The crest width will be 12 feet with a 4:1 horizontal to vertical (H:V) upstream slope from the crest that terminates at the top of bedrock. The upstream slope will terminate at the top of existing bedrock and a 25-foot wide horizontal bedrock bench. The bedrock bench will be graded to a 6:1 slope to the reservoir bottom. Material Processing The claystone will be processed in place to within ±2% of optimum moisture. The claystone wilt be ripped in place to a depth of approximately 1' by shanks on a D-8, or comparable. Water will be injected into the ripped zone through tines on a water truck that will also mix the claystone. The processed bedrock will be transported to the slope liner by graders that will strip approximately 4" of the material over a large area, further mixing the bedrock. Foundation No material shall be placed in any portion of the embankment until the foundation for each section has been deaahered, stripped, suitably prepared, and has been approved by the Engineer. A foundation check sheet shall be signed by the Contractor and Engireer before soil placement. All cavities, depressions and irregularities, within the area to be covered by embankment and which extend below or beyond the established lines of excavation for dam embankment foundations, shall be filled with embankment materials as specified for the overlying embankment. The weathered claystone bedrock shall be stripped to a depth of at least 1' beneath the slope liner/ Weathered claystone contact. Care shall be taken that slabs of bedrock are not dislodged during the foundation bedrock stripping. The entire foundation shall be rolled and compacted with a sheepsfoot compactor prior to placement of the first lift of slope liner soil. A smooth drum roller shall not be used to compact the claystone foundation. Cutoff Trench The cutoff trench shall extend 4' below the foundation surface measured after the weathered or top 1' foot of bedrock is removed. After excavation a sheepsfoot compactor should be used to compact the bottom and sides of the cutoff trench before embankment soil placement. The suitability of each part of the foundation for placing embankment materials thereon, and of all materials for use in embankment construction, will be determined and approved by the Engineer. No embankment material shall be placed in the embankment when either the material or the foundation or embankment on which it would be placed is frozen. In any separate portion ofcut-off trench or embankment being constructed, each layer of each zone shall be constructed continuously and approximately horizontal for the width and length of such portion at the elevation of the layer. If traverse slopes are required in the cut-off trench embankment, slopes shall be no steeper than 4:1 (horizontal to vertical). Material Placement The earthfill material shall be placed in the slope liner in continuous and approximately horizontal layers, not more than 9" loose lift thickness. The combined excavation and placing operations shall be such that the materials will be sufficiently blended to secure the best practicable degree of compaction and stability. To achieve sufficient blending, in addition to the insitu bedrock processing, a disc will be required during placement of any slope liner fill. The material shall be compacted to a minimum of 95% of the Standard Proctor as described in ASTM D698. The