A. This project consists of an immediate upgrade to the solids handling and dewatering facilities to address failed infrastructure. Digester 1 will be retrofit to an aerated solids holding tank with diffused air for mixing and aeration. A decanter will be provided to thicken the solids and send supernatant back to the treatment process. Two blowers (duty/standby) will provide the aeration to the solids holding tank coarse bubble diffusers. HVAC improvements will be required in the digester control building to cool the blowers and to comply with NFPA 820 electrical code. The existing thickener building will be repurposed as a dewatering building and retrofit with two new screw presses for added dewatering capacity. HVAC improvements will also occur at the repurposed dewatering building. The Schwing Bioset screw presses have already been procured by the City. Dedicated screw conveyors are proposed for each screw press. Emulsion polymer make-up systems will also be installed. Duty/standby rotary lobe screw press feed pumps will be installed in the basement of the digester control building.
B. This project includes all labor, equipment, materials, installation, and related appurtenances as shown on the drawings and described in the specifications. Also included in the project is mobilization, site work, demolition of existing facilities, coatings, all piping, valves, pumps and equipment, site civil, yard piping, bypass pumping, electrical, HVAC, site restoration, startup, and all other items required to make the solids handling facilities complete and operational.
C. Existing dewatering equipment and facilities retained at this phase will consist of the primary clarifiers, belt filter press, (3) anaerobic digesters, thickener building
(repurposed as a dewatering building), and digester control building.