Belvidere Wastewater Treatment Facility Clarifier Rehabilitation

a. Tank draining will be performed by the on-site plant operators. The Plant operators will also hose down the two BESST Clarifiers and the Aeration tank and pump off any sludge and residue. Service water is permissible to be used. b. Contractor shall remove an approximately twelve-foot (Contractor shall field verify) section of threaded 1½” diameter air drop pipe and replace with a new section of 1 ½” diameter threaded galvanized air drop pipe at all locations denoted on the Contract Drawings. Temporary covers shall be provided at all openings in the exposed aeration system. Prior to the installation of the new air drop piping, Contractor shall remove isolation valves and fittings, where indicated on the Contract Drawings, and reinstall to correct valve operator orientation. New air drop pipe will be threaded into the relocated isolation valve and reconnected at the diffuser with a new 1 ½” galvanized union. c. Contractor shall provide adequate provisions to prevent any material removed during tank/clarifier surface preparation and any coating overspray from migrating to the in-service tanks/clarifiers. d. Contractor shall prepare all surfaces for application of coatings as denoted in the Specifications and on the Contract Drawings and apply protective coatings per manufacturer’s recommendations. e. Concrete walls and metal clarifiers shall be inspected for the presence of defects by a NACE Level 2 inspector. Contractor shall coordinate and provide access to the tankage for inspection. Repairs to the clarifier units shall be made as required by the Authority’s Engineer. All repairs shall be made in accordance with the Contract documents. f. Contractor shall remove and replace an approximately four (4) foot section on each of the clarifier internal vertical structural supports. Repairs shall be made in accordance with the Contract documents. g. Coated surfaces shall be allowed proper time to cure as recommended by the manufacturer prior to additional coating, if required by manufacturer’s recommendations for the specific coating system. h. Process shall be repeated for each of the remaining two tanks.

Division 09 -	Finishes, Painting and Coating, High-Performance Coatings, Chemical-Resistant Coatings, Special Coatings, Steel Coatings, Interior Steel Coatings, Exterior Steel Coatings, Cementitious Coatings.
Division 46 -	Water and Wastewater Equipment, Clarifier Equipment.