Biogas And Biosolids Evaluation: Digester 1 Cleaning

The City of San Mateo is soliciting bids for project 46t090, which involves the cleaning and interior surface preparation of anaerobic Digester 1 at the San Mateo Wastewater Treatment Plant. The scope of work includes the removal and offsite disposal of approximately 150,000 gallons of digester contents, high-pressure washing of all interior surfaces, and the installation of engineered scaffolding to be left in place for a future repair and coating contract. The contractor is responsible for abrasive blast cleaning of carbon steel substrates to support inspection and condition assessment, though final coating application is excluded from this specific contract. The estimated base construction cost is 1,100,000 dollars with a completion timeframe of 130 working days. Bids are due by July 16, 2026, and must comply with strict safety and regulatory standards, including Cal/OSHA Title 8 for scaffolding and permit-required confined space entry procedures. Contractors must provide a site-specific Health and Safety Plan and adhere to state prevailing wage or City of San Mateo minimum wage requirements. Evaluation is based on mandatory compliance, including the submission of payment and performance bonds, valid contractor licenses, and registration with the California Department of Industrial Relations. Technical requirements specify adherence to SSPC and ISO standards for surface cleanliness, dust levels, and surface profile measurements, with all work performed onsite at the facility located in San Mateo, California.