Specifications include, but are not limited to: Reinforced earth walls shall be constructed in accordance with the manufacturer’s or system designer’s approved specifications and shop drawings. Fill material placed in the reinforced soil zone for the reinforced earth retaining walls shall meet corrosion, gradation, placement and compaction requirements in accordance with the manufacturer’s or system designer’s specifications and shop drawings and other requirements stated in the Special Provisions. In the absence of any such requirements, fill shall be Gravel Borrow placed in horizontal layers not exceeding 10 inches (before compaction) and each layer shall be compacted to not less than 95% of maximum dry density as determined by AASHTO T-180. In those locations not accessible for normal placing and rolling, fill shall be placed in lifts not to exceed 8 inches before compaction and compacted by means of mechanical tampers, or suitable vibratory equipment. For minor operations, hand tamping with heavy iron tampers may be used.