Specifications include, but are not limited to: 1) Excavate a test hole within the area where the first tank will be set to locate the water table and inspect the soil profile. 2) Assemble the buoyancy restraint anchors for the first tank according to the details in the section and plan drawings. 3) Clear the organics and topsoil from the site of the first tank to be installed and stockpile it. 4) Complete the tank excavation as deep as possible, but no deeper than eight feet, digging as close to the water table as possible without causing the banks to cave. Stockpile this material for backfilling the top half of the tank and building up the pump truck offload/load platform. 5) Move one tank from the boat harbor and set the tank level in the excavation. Set the buoyancy restraint anchors. Note: No personnel are to enter the excavation. Stake the anchor cables on the ground at the top of the hole. This sequence can be reversed with the buoyancy anchors set first if desired by the contractor. 6) Backfill with clean coarse grained sand to halfway up the side of the tank and pack it with the excavator bucket as it is placed. This material will be brought from the gravel pit. Care must be exercised to prevent damage to the tank wall. 7) When the excavation is filled halfway up the tank, the excavation should then be between two and four feet deep and safe for personnel to enter. Once it is determined that it’s safe for personnel to enter the excavation, place the two inch wide steel strapping in the buoyancy restraint guides on the top half of the tank, unstake the anchor cables and fasten them to the straps with cable ties, and connect the cables from both sides of the tank on top with wire rope clips as shown in the section drawing. 8) Fill the excavation to the natural ground elevation with clean coarse or medium grained sand and pack it with the excavator bucket as it is placed. Cover the tank to a depth of one foot with material stock piled from clearing the roadway and tank site. Care must be exercised to prevent damage to the tank wall. 9) Repeat this sequence for the second tank.
