DATE: October 7, 2026
TO: Honorable Mayor and City Council Members
Honorable President and Board Members
FROM: Utilities Department
2026-078
REQUEST FOR CITY COUNCIL AND
CORONA UTILITY AUTHORITY ACTION
SUBJECT:
SECOND AMENDMENT TO PROFESSIONAL SERVICES AGREEMENT WITH NARASIMHAN CONSULTING SERVICES, INC. FOR DESIGN AND ENGINEERING
SERVICES
EXECUTIVE SUMMARY:
This staff report asks the City Council to consider approval of the Second Amendment to the Professional Services Agreement with Narasimhan Consulting Services, Inc. for design and engineering services related to 1,2,3-Trichloropropane and Per- and Polyfluoroalkyl Substances treatment.
RECOMMENDED ACTION:
That the City Council:
a. Approve the Second Amendment to the Professional Services Agreement with Narasimhan Consulting Services, Inc. for 1,2,3-Trichloropropane and Per- and Polyfluoroalkyl Substances remediation and treatment increasing the agreement by $292,890 for a total not to exceed amount of $622,890. b. Authorize the City Manager, or his designee, to execute the Second Amendment to the Professional Services Agreement with Narasimhan Consulting Services, Inc. for 1,2,3-Trichloropropane and Per- and Polyfluoroalkyl Substances remediation and treatment for a total agreement amount $622,890, including the ability to negotiate and execute non-substantive changes and extensions, purchase orders and amendments up to $62,289 or 10% of the contract amount as authorized by Corona Municipal Code Section 3.08.070(G).
c. Authorize the City Manager, or his designee, to issue a Purchase Order to Narasimhan Consulting Services, Inc. in the amount of $622,890. d. Authorize an appropriation in the amount of $336,812 from the Water Utility Fund (FD_1570) to the PFAS and 1, 2, 3-TCP Remediation, Capital Improvement Project No. UT-2024-10.
That the Corona Utility Authority review, ratify, and to the extent necessary, direct the City Council to take the above actions.
BACKGROUND & HISTORY:
On September 20, 2023, the City Council approved a Professional Services Agreement with Narasimhan Consulting Services, Inc. (NCS Engineers) to provide design and engineering services for 1,2,3-Trichloropropane (1,2,3-TCP) and Per- and Polyfluoroalkyl Substances (PFAS) remediation and treatment.
PFAS are a class of manufactured chemicals that are persistent in the environment and may accumulate in water sources. Scientific research has identified potential adverse health effects associated with exposure to certain PFAS. As state and federal PFAS regulations continue to evolve, the City must be prepared to comply with applicable drinking water standards and ensure the continued delivery of safe and reliable potable water.
Additionally, 1,2,3-TCP is also a manufactured chemical that can persist in groundwater and is classified as a carcinogenic substance. To enhance the City's ability to address 1,2,3-TCP and PFAS in its water supply, NCS Engineers developed design plans for modifications to the existing well treatment facilities, as well as upgrades to the City's Park Granular Activated Carbon (GAC) Treatment Plant.
ANALYSIS:
Following completion of the initial plans, specifications, and cost estimates, staff identified concerns regarding the limited size of the proposed treatment facility at the Well 7A site, particularly with respect to chemical delivery and handling. Staff also raised concerns regarding the proposed facility's aesthetic impacts and compatibility with the surrounding community. To address the Well 7A concerns, two locations have been identified for the well’s water diversion and treatment, the City’s GAC Treatment Plant and Well 8A. When evaluating alternative treatment configurations for the wells, staff also requested that NCS Engineers revise the design to incorporate treatment of Well 17 and provide greater flexibility to accommodate future treatment needs for additional wells.
The revised approach would consolidate treatment for both Well 8A and Well 17 at a centralized facility at the Well 8A site, providing the City with greater operational flexibility and the ability to address future water quality needs more efficiently.
Under the revised Scope of Work, NCS Engineers will revise the drawings, specifications, and associated design documents to:
1. Provide treatment for water from Well 8A and Well 17 at a centralized treatment facility located at the Well 8A site.
2. Divert Well 7A water to the City's GAC Treatment Plant through installation of a new well collector line in the future.
3. Provide the option to divert Well 7A water to Well 8A site for treatment through some valving modification.
The revised treatment configuration is intended to provide a more efficient and flexible approach to managing 1,2,3-TCP and PFAS, while supporting regulatory compliance and the City's ability to provide safe and reliable potable water. The centralized approach also addresses Staff's concerns regarding facility size, chemical delivery and handling, and potential aesthetic impacts at the Well 7A site.
The existing NCS Engineers agreement expired on September 30, 2025. After reviewing the cost estimate associated with the revised Scope of Work, staff recommends that the City Council approve the Second Amendment to the Professional Services Agreement with Narasimhan Consulting Services, Inc. to provide the additional design and engineering services necessary to support 1,2,3-TCP and PFAS treatment improvements and extend the term of the agreement through June 2030..
FINANCIAL IMPACT:
Approval of the recommended actions will result in an appropriation in the amount of $336,812 to the PFAS and 1, 2, 3-TCP Remediation, Capital Improvement Project No.
UT-2024-10 within the Water Utility Fund (FD_1570).
Contract Amount
Original Contract $300,000
First Amendment $30,000
Requested Second Amendment $292,890
Revised Contract Amount $622,890
Budget/Appropriation
Current Appropriation $310,932
Contract Amount
Less: Actual Expenditure ($292,565)
Remaining Appropriation $18,367
Requested Second Amendment $292,890
10% Contingency $62,289
Total Funding Need $355,179
Less: Remaining Appropriation ($18,367)
Additional Appropriation Requested $336,812
ENVIRONMENTAL ANALYSIS:
These actions are exempt from the California Environmental Quality Action (CEQA), as the actions are not a “project” as defined by CEQA (PRC Section 21065 and CEQA Guidelines Section 15378), guidelines which define a “project” as the whole of an action, which has a potential for resulting in either a direct physical change in the environment, or reasonable foreseeable indirect physical change in the environment, and that is an activity directly undertaking by any public agency including public works construction and related activities. These actions involve the approval of an amendment to a professional services agreement. Therefore, no environmental analysis is required at this time.
PREPARED BY: AFTAB HUSSAIN, ASSISTANT UTILITIES DIRECTOR REVIEWED BY: TOM MOODY, UTILITIES DIRECTOR
ATTACHMENT:
1. Exhibit 1 – Second Amendment