CITY OF SAN MATEO
CITY OF SAN MATEO
Agenda Report
City Hall
330 W. 20th Avenue
San Mateo CA 94403
www.cityofsanmateo.org
Agenda Number: 16 Section Name: {{section.name}} Account Number: 72-4671 File ID: {{item.tracking_number}} TO: City Council
FROM: Alex Khojikian, City Manager
PREPARED BY: Public Works Department
MEETING DATE: November 18, 2024
SUBJECT:
Wastewater Treatment Plant Biogas and Biosolids Evaluation — Agreement RECOMMENDATION:
Award a professional consulting services agreement with Brown and Caldwell for the Wastewater Treatment Plant Biogas and Biosolids Evaluation in an amount not to exceed $1,249,180; establish a contingency reserve of $426,000; and authorize the Public Works Director to execute the agreement in substantially the form presented and execute any necessary amendments within the contingency amount.
BACKGROUND:
The Clean Water Program (CWP) Annual Major Components (AMC) Projects include several capital improvement projects that are currently under development or under construction and intended to upgrade or rehabilitate aging infrastructure at the portion of the City’s Wastewater Treatment Plant (WWTP) that will still remain in operation even after the new liquid treatment facilities are commissioned in 2025. The WWTP Biogas and Biosolids Evaluation (Project) is one of these projects, which will assess ways to improve the condition, reliability, operations, and maintenance of the City’s two anaerobic digesters and sludge storage tank, explore options for and feasibility of beneficial use of solids treatment byproducts (specifically biogas and biosolids), and analyze the impact on overall energy production and costs. The project includes several components which will culminate in an implementation plan and a capital improvement roadmap for future recommended projects.
The Clean Water Program (CWP) Annual Major Components (AMC) Projects include several capital improvement projects that are currently under development or under construction and intended to upgrade or rehabilitate aging infrastructure at the portion of the City’s Wastewater Treatment Plant (WWTP) that will still remain in operation even after the new liquid treatment facilities are commissioned in 2025. The WWTP Biogas and Biosolids Evaluation (Project) is one of these projects, which will assess ways to improve the condition, reliability, operations, and maintenance of the City’s two anaerobic digesters and sludge storage tank, explore options for and feasibility of beneficial use of solids treatment byproducts (specifically biogas and biosolids), and analyze the impact on overall energy production and costs. The project includes several components which will culminate in an implementation plan and a capital improvement roadmap for future recommended projects.
The City has had to respond to and address deficiencies and improvements with the anaerobic digestion and solids handling system. A number of these past efforts have been short-term, reactive solutions to keep systems operational. A long-term, cost-efficient solution needs to be developed through this Project to maintain reliability, ease of operability, and redundancy of the digestion system.
In April 2022, staff issued a Request for Qualifications for on-call professional services, which included alternatives analyses and engineering studies, design services, bid period services, engineering services during construction, and
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operational support. In August 2022, City Council awarded two On-Call Consulting Services Agreements to Carollo Engineers and Brown and Caldwell.
In June 2024, staff provided Carollo Engineers and Brown and Caldwell a Request for Proposals to provide services for the Biogas and Biosolids Evaluation Study. In August 2024, staff received proposals for this work from the two firms. Staff evaluated the proposals and determined Brown and Caldwell as the best qualified consultant to provide the scope of work and expertise required for this Project. This study was previously envisioned to be issued under the existing On-Call Consulting Services Agreement with Brown and Caldwell; however, due to the cost of the study, a separate agreement is needed.
Staff negotiated a fee of $1,249,180 to complete the Project’s base scope of services, which includes general project management services; Digester 1 cleaning and assessment and subsequent design, bid period assistance, and construction phase services for recommended improvements; evaluations and field investigations of the solids processing facilities; and reporting.
The level of effort associated with completing evaluations and field investigations of Digester 1, Digester 2, and the sludge storage tank makes up about 40 percent (or $501,397) of the negotiated fee, primarily due to the challenges and complexity of safely inspecting inside of an egg-shaped confined space. The base scope of work includes an interior scaffolding approach for inspecting Digester 2, but not for Digester 1 or the sludge storage tank. With a scaffolding system erected, the consultant will perform ultrasonic testing, dry film thickness testing, and pit depth measurements inside Digester 2. Earlier this year, Council approved a separate contract for repairing/replacing the mixer inside Digester, which required Digester 2 to be taken out of operation; the other two facilities remain in operation. Staff incorporated the Digester 2 interior scaffolding in the base scope of work since it is not currently in operation. The approach to potentially utilize scaffolding to perform interior inspections of the other two facilities is discussed further below and strategically included as part of the requested contingency reserve.
The base scope and fee of this Project also includes assessing and reporting the utilization of biogas and biosolids for beneficial and economic use in response to evolving regulations and policies with respect to waste management, landfill disposal, and environmental protection. In addition, the new WWTP liquid treatment facilities that are under construction and will be operational next year will cause operational changes to the anaerobic digestion and solids handling system; the Project will analyze these changes and recommend optimizations to the systems. The Project will also evaluate the use of biogas to potentially offset the anticipated increase in operational electricity costs once the new WWTP liquid treatment facilities are commissioned. Grants, credits, and loans available from federal, state, and local programs to fund the recommended capital improvements will also be identified as part of the evaluation and reports. The results of the Project will be used to plan for future capital planning needs and define the scope of other WWTP projects.
Staff requests a contingency reserve to potentially include scaffolding installations to complete interior condition assessments for the sludge storage tank and Digester 1 facilities. These two facilities must remain operational while Digester 2 is being evaluated. It is critical to evaluate the interiors of these facilities; however, staff recommends a phased approach to evaluate the efficacy of using interior scaffolding during the Digester 2 evaluations, along with evaluating if alternate interior non-scaffolding approaches can be completed. Brown and Caldwell’s proposed fee to include interior scaffolding for the sludge storage tank and Digester 1 is conservatively estimated at $326,000. A future amendment will be required to support the interior evaluations of the other two facilities; if less expensive alternatives are not feasible, this $326,000 scope will need to be quickly amended into the agreement to not impact the schedule and minimize any period of time where solids processing facilities are out of operation. To address any other potential changes or unknowns, an additional $100,000 is also requested to be added. This recommended phased strategy requires a total contingency reserve of $426,000.
On agreements of this nature, Council has typically approved contingency reserves that equal 10 to 20 percent of the fee.
In this case, staff’s $426,000 contingency request is 34 percent of the fee. Establishment of this higher contingency reserve is recommended to provide staff the flexibility to evaluate alternate approaches to conduct interior evaluations of the
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other two facilities, while allowing a timely start of the base scope of services and timely execution of anticipated and required amendments to the scope and fee.
BUDGET IMPACT:
There are sufficient funds available in the CWP WWTP Annual Major Components (46t090) project account to fund this agreement and contingency reserve.
ENVIRONMENTAL DETERMINATION:
This Project is categorically exempt from CEQA review as an “existing facility,” in that it consists of the operation, repair, maintenance, permitting, leasing, licensing, or minor alteration of existing public or private structures, facilities, mechanical equipment, or topographical features, involving negligible or no expansion of existing or former use. (CEQA Guidelines Section 15301.)
NOTICE PROVIDED
All meeting noticing requirements were met.
ATTACHMENTS
Att 1 - Agreement
STAFF CONTACT
Thomas Ruark, Project Manager II
[email protected]
(650)522-7280
Deryk Daquigan, Deputy Director of Public Works
[email protected]
(650)522-7287
Matthew Fabry, Director of Public Works
[email protected]
(650)522-7303