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~ 1. Stripping SPECIFICATIONS FOR IMPOUNDMENTS Strip all construction areas of vegetation and debris. Remove and stockpile all topsoil on the construction area. 2. Embankment Material The material will be clay-silt with little sand and medium placticity. The material will be used at each impoundment site. 3. Moisture and Compaction The distribution of materials shall be such that the compacted material will be homogeneous and Eree from lenses, pockets, streaks, or other imperfections. The material shall be deposited in horizontal layers six to twelve inches thick. The excavating and placing operations shall be such that the material when compacted will be blended sufficiently to secure the best practicable degree of compaction, impermeability, and stability. Compaction and moisture content shall be adequate for use as an earthen fill dam. 4. Principal Spillway The conveyance will be 36-inch or 48-inch diameter corrugated metal semi- circular flume. The flume shall be set in a concrete base in excavated mate- rial centered in the emergency spillway. 1 5. Emergency Spillway The spillway will be a single spillway on the side of the impoundment. The entry will be smooth and flat with walls on 3:1 slopes. 6. Cutoff Trench The cutoff trench will be 5 feet in depth with a 10-foot wide floor. The walls will have 1:1 slopes. The cutoff trench will be backfilled with the salve material [o be used in [he embankment and placed in accordance with Article 3. 7. Regrading Borrow areas at each site will be regraded as needed to prevent erosion or ponding of water. The regrading will blend with the natural topography at each site. 8. Size of Embankment Total height of embankment will include a 5Y, allowance for settling. Width at the top of the embankment will be 15 feet with side slopes of 3H:1V on the downstream side and 2H:1V on the upstream side. CRF/jb 8/86 L Revised 8/86