REPORT TO COUNCIL
SUBJECT
Title
Authorization to Amend an Existing Contract for Design of a Sodium Hypochlorite Disinfection System for the Water Pollution Control Plant (F14-75)
Report
REPORT IN BRIEF
Approval is requested to amend an existing contract with HDR Engineering, Inc. (HDR) of Walnut Creek for design services associated with a new sodium hypochlorite disinfection system at the Water Pollution Control Plant (WPCP). The amendment will increase the total value of the contract by $75,000, from $360,180 to $435,180. The recommended increase includes $67,663 for additional design services and $7,337 for additional engineering services during construction. The added services are for operational improvements to the disinfection system, recommended as the result of preliminary studies conducted as part of the initial contract award.
ENVIRONMENTAL REVIEW
This amendment to an existing design contract is not a project as defined in Section 15378 of the California Environmental Quality Act (CEQA).
BACKGROUND AND DISCUSSION
The final treatment process at the WPCP currently disinfects waste water using gaseous chlorine and then neutralizes the chlorine with bi-sulfate prior to Bay discharge. The recycled water production process also uses gaseous chlorine for disinfection and residual chlorine. Gaseous chlorine has been used at the WPCP for decades and was historically the disinfectant of choice due to its effectiveness and low cost. However, gaseous chlorine is a very dangerous chemical and as a result many treatment plants are eliminating its use in favor of liquid chlorine (technically sodium hypochlorite or bleach). This product is much less dangerous and therefore reduces the potential hazards to plant workers and the surrounding community.
An initial design scope to convert the plant disinfection system from gas to liquid chlorine was awarded to HDR on February 26, 2013 (RTC No. 13-048). A portion of the work scope included preliminary studies to evaluate opportunities to improve the WPCP disinfection process. The 2013 RTC indicated that, pending the results of the analyses, a contract amendment could be brought forward to implement recommendations. HDR Engineering, Inc. has recommended an option to add redundancy to the dechlorination process. The option adds an additional chlorine analyzer and bi-sulfite dosing point to the Bay discharge line to assist the WPCP in meeting the regulatory requirements for the level of chlorine residual in the water discharged into the Bay. The additional design proposed will include the necessary controls required to operate and monitor the new equipment. These additional improvements will help to provide a layer of redundancy in the system in an effort to minimize future regulatory violations.
FISCAL IMPACT
Total costs for the design contract will be $435,180, which consists of the original contract award of $360,180 and the proposed amendment of $75,000. Budgeted funds are available in Capital Project 829430 (WPCP Chlorine Conversion), funded by the Wastewater Management Fund.
It should be noted that a 15% contingency in the amount of $54,027 was approved by Council with the initial contract award in 2013, which potentially increases the total contract value from $435,180 to $489,207. However, use of contingency funding is reserved for unforeseen conditions, and would neither be used for this type of contract amendment nor be included in the actual executed contract (contingencies do not appear in contracts so as not to artificially increase the amount negotiated and awarded to the consulting firm).
PUBLIC CONTACT
Public contact was made by posting the Council agenda on the City's official-notice bulletin board outside City Hall, at the Sunnyvale Senior Center, Community Center and Department of Public Safety; and by making the agenda and report available at the Sunnyvale Public Library, the Office of the City Clerk and on the City's website.
RECOMMENDATION
Recommendation
Authorize an amendment to an existing contract, in substantially the same format as Attachment 1, with HDR Engineering, Inc., for design services associated with a new sodium hypochlorite disinfection system at the Water Pollution Control Plant to increase the total contract value by $75,000 for additional services, bringing the total contract value to $435,180.
Staff
Prepared by: Pete Gonda, Purchasing Officer
Reviewed by: Grace Leung, Director, Finance
Reviewed by: John Stufflebean, Director, Environmental Services
Reviewed by Kent Steffens, Director, Public Works
Approved by: Robert A. Walker, Interim City Manager
Attachments
ATTACHMENTS
1. Draft Amendment to Consultant Services Agreement