The project generally consists of the furnishing of all labor, materials, equipment, appurtenances, and incidentals as required to properly fabricate, construct, inspect and test the construction items required for the removal, screening, and disposal of all accumulated digester contents within three (3) primary digesters and one (1) secondary digester into Sludge Lagoon #3, wash with non-potable water all the tank walls, roof, piping and otherwise prepare the four digesters for inspection, remove and replace the floating gasholder cover complete with pressure relief valves, flame arrestors, access manholes and associated appurtenances on Secondary Digester B, remove and replace various sizes of plug valves in the Digester Pump Station building including pneumatic actuators, modify piping, tank penetrations, and additional plug valves for future improvements, and modify the digester gas piping for Digester B and other work as indicated.