Digester and Centrifuge Sludge Feed Tank Cleaning

Pima County has issued an Invitation for Bids (IFB-2500018281) for Digester and Centrifuge Sludge Feed Tank Cleaning services at the Tres Rios Water Treatment Facility located in Tucson, Arizona. The multi-supplier contract seeks to establish a framework for cleaning six digesters, each with a 1.5 million gallon capacity, with an anticipated cleaning of one digester per year. Suppliers must have been in business for at least three consecutive years and possess a Confined Space Entry Program that meets OSHA regulations. The contract requires suppliers to provide comprehensive tank cleaning services, including removing solids, hydro-washing, and screening materials, with all work to be performed at 7101 N. Casa Grande Highway. Key deliverables include moving water into tanks, discharging water and screened contents to a county-designated storage facility, and ensuring all screenings pass the Paint Filler Test before disposal. The procurement timeline includes a remote pre-bid conference on October 22, 2025, with final bids due on November 13, 2025, to be submitted through the BidNet solicitation portal.

The contract has specific provisions favoring Small Business Enterprise (SBE) certified firms for contracts not exceeding $500,000, with awards to be made to the lowest responsive and responsible bidder. While specific award values are not explicitly stated, the county will provide water, power, and assistance with degassing and opening/closing digesters, suggesting a collaborative approach to the project. The contract term is one year, with options for four additional one-year renewals, providing potential long-term opportunity for qualified vendors. Suppliers must demonstrate comprehensive capabilities in industrial tank cleaning, including specialized equipment, safety protocols, and environmental compliance. The county's procurement approach emphasizes both technical capability and cost-effectiveness, with a clear preference for local and small business participation in the bidding process.