HomeMy WebLinkAboutEngineering & Operations MINUTES 07-10-23Page 2 of 11
LCENTRAL SAN
BOARD OF DIRECTORS:
REGULAR MEETING OF THE
BARBARA D. HOCKETT
CENTRAL CONTRA COSTA
President
SANITARY DISTRICT
MARIAHNLEN
President Pro Pro Teen
ENGINEERING & OPERATIONS
MICHAEL R. MCGILL
COMMITTEE MINUTES
EDIWNGTON CKI
FLORENCE T. T EDI TON
Monday, July 10, 2023 PHONE: (925) 228-9500
9:00 a.m. FAX.- (925) 372-0192
www.centralsan.org
Committee:
Chair Tad Pilecki
Member Mike McGill
Guest: Tracy Stigers, Brown and Caldwell
Staff. -
Katie Young, Secretary of the District
Greg Norby, Deputy General Manager — Operations
Philip Leiber, Deputy General Manager — Administration (arrived during Item 3.a.)
Edgar Lopez, Provisional Director of Engineering and Technical Services
Neil Meyer, Provisional Director of Operations
Danea Gemmell, Planning and Development Services Division Manager (joined during Item
3. a.)
Nitin Goel, Operations Optimization Division Manager
Alan Weer, Plant Operations Division Manager (joined during Item 4.a.)
Clint Shima, Senior Engineer
Craig Mizutani, Senior Engineer
Michael Cunningham, Associate Engineer
William Grant, Associate Engineer
Stacey Durocher, Administrative Services Assistant
Call Meeting to Order
Chair Pilecki called the meeting to order at 9:00 a.m.
2. Public Comments
None.
July 20, 2023 Regular Board Meeting Agenda Packet - Page 96 of 112
Page 3 of 11
Engineering & Operations Committee Minutes
July 10, 2023
Page 2
3. Items for Committee Recommendation to Board
*a. Review draft Position Paper to award a construction contract in the
amount of $11,449,000 to C. Overaa & Co., the lowest responsive and
responsible bidder for Aeration Basins Diffuser Replacement, Phase 1,
District Project 100019; include award of an additive bid item in the
amount of $1,213,000 for seismic upgrades; execute a professional
engineering services agreement in an amount not to exceed $1,000,000
with HDR Engineering, Inc. to provide engineering services during
construction; and find the project is exempt from the California
Environmental Quality Act (CEQA)
Mr. Grant reviewed the presentation included in agenda materials.
Chair Pilecki inquired about the seismic scope of work. Mr. Grant stated
that the additive bid item is for Fiber -Reinforced Polymer (FRP) seismic
strengthening. The FRP wrap will be installed at strategic locations in the
tanks to strengthen the concrete and bring the aeration basins up to
seismic code.
Member McGill asked if the new air piping system will be placed above the
floor as opposed to the current system being underneath the floor of the
tank. Mr. Grant stated the new system will be placed slightly above the
floor allowing debris to be washed away and drain properly as opposed to
settling on the bottom.
Mr. Grant responded to questions posed by Chair Pilecki regarding the
existing plenums and the purpose of the baffle walls stating that the
existing plenums will be demolished and a new properly sloped concrete
slab will be added in place of the plenums, and the baffle walls will allow
staff to operate in a step feed mode in the future should nutrient removal
requirements change. Mr. Lopez added that the baffle walls are not only
being added as part of the seismic retrofit but will allow for better efficiency
and for staff to control flows as well as the aeration process better. He
stated the plenums were rehabilitated many years ago and were difficult to
maintain and was where most of the leaks were coming from.
Member McGill inquired whether staff can still see air leaking during the
rain. Mr. Lopez stated that most of those issues were resolved under
another project, but leaks are more common in the tunnels now due to
cracking.
Chair Pilecki asked if the hissing noises in the groundwater relief valves
were still problematic and if those were being addressed. Mr. Lopez stated
the relief valves will also be rehabilitated.
July 20, 2023 Regular Board Meeting Agenda Packet - Page 97 of 112
Page 4 of 11
Engineering & Operations Committee Minutes
July 10, 2023
Page 3
Member McGill inquired about the engineers' estimate being so high. Mr.
Grant responded that some of the quotes received from suppliers during
design were high. For example, the stainless -steel piping quote was high
but the price that came in during bidding was approximately $1 million
lower. Other contributing reasons for this include staff time spent with the
contractors resulting in comprehensive bids and competitive pricing, as
well as the diffuser system being pre -purchased by Central San and
installed by the contractor.
Member McGill asked if the project was eligible for grant funding. Ms.
Gemmell stated that staff did apply for government funding but was not
selected. She stated future funding could be possible but would be a few
years out.
Chair Pilecki recommended adding a sentence to the end of the 3ra
paragraph in the Background section stating that Phase 2 will address the
remainder of the project and is scheduled for 2026-27.
In response to Chair Pilecki regarding escrow documents, Mr. Lopez
stated that the District often requests escrow documents on projects over
$10 million in addition to the normal bid documents.
Chair Pilecki asked if the aeration tanks will be retrofitted to seismic level
4. In response, Mr. Lopez stated they will be retrofitted to the current
standard for wastewater facilities.
COMMITTEE ACTION: Recommended Board approval.
b. Review draft Position Paper and authorize the General Manager to
purchase natural gas through an existing service agreement with Shell
Energy North America, LP for the period of January 1, 2025 through
December 31, 2025 up to 1,200 dekatherms per day at a price not to
exceed $7.00 per dekatherm, excluding transportation service costs
Mr. Shima reviewed the draft Position Paper included in agenda materials.
In response to a question posed by Member McGill about how much
money is spent in total for natural gas during the year, Mr. Shima stated
approximately $3 million including commodity and transportation costs.
Chair Pilecki asked if there was a cap on landfill gas and if staff anticipates
being over budget. Mr. Shima said that landfill gas has a cap of $6 per
dekatherm and should not be over budget, however electricity will be over
budget due to an unscheduled outage on Cogen. Chair Pilecki also asked
if staff knew how long landfill gas would be available. Mr. Shima stated
based on the information he has received approximately 10 years.
July 20, 2023 Regular Board Meeting Agenda Packet - Page 98 of 112
Page 5 of 11
Engineering & Operations Committee Minutes
July 10, 2023
Page 4
Chair Pilecki asked if staff plans to do a study on landfill gas, and whether
it is anticipated that natural gas prices will continue to rise given the
current political climate. Mr. Shima said prices per dekatherm are quite
low for natural gas, and the five-year average supply looks good. Mr.
Shima also stated that staff has been working with a natural gas
consultant and has received no indications of major changes to affect
future supply.
Member McGill asked if landfill gas counts against cap and trade. Mr.
Shima stated minimally, but not as much as natural gas usage.
In response to Member McGill's question regarding possibly acquiring
natural gas from Keller Canyon, Mr. Shima responded stating that staff
has not explored that option but will look at it.
The Committee had no further questions.
COMMITTEE ACTION: Recommended Board approval.
4. Other Items
a. Receive update for the Solids Handling Facilities Improvements, Phase 2,
District Project 100030
Mr. Goel provided an overview of the presentation included in the agenda
materials.
Member McGill suggested a workshop for the entire Board on this subject
in the future.
Mr. Goel stated the existing multiple hearth furnaces have been reliably
converting solids from wastewater to ash for more than 45 years. The
Solids Handling Facilities Improvement Project, Phase 1A will address
immediate needs such as seismically reinforcing the building, replacing
equipment, and upgrading air pollution control equipment. The Solids
Handling Improvement Phase 2 planning when complete will identify the
future solids handling process.
Member McGill inquired if the public would buy the ash instead of paying
for delivery and removal. Mr. Lopez stated staff has looked at other uses
for the ash in the past but has not done a Request for Proposal (RFP) for
other users to purchase the ash.
Ms. Stigers also responded stating Brown and Caldwell has explored
various viable outlets, and there may be some additional uses in the
future, but the market for ash today in the Bay Area is too small and there
July 20, 2023 Regular Board Meeting Agenda Packet - Page 99 of 112
Page 6 of 11
Engineering & Operations Committee Minutes
July 10, 2023
Page 5
is not enough awareness or desirability, so this would be more of a market
development activity to see if there were other users willing to pay for the
ash.
Chair Pilecki commented that the only other alternative would be to landfill
the ash and pay fees, and staff has already determined having it hauled
away is the most cost-effective way to dispose of our ash at this time.
Staff responded to all questions, and the Committee suggested having bi-
yearly updates as well as a workshop for the entire Board in the future.
COMMITTEE ACTION: Received the update.
5. Announcements
None.
6. Suggestions for Future Agenda Items
a. Receive list of upcoming agenda items and provide suggestions for any
other future agenda items
As mentioned in Item 4.a., a Board workshop regarding the Solids
Handling Facilities Improvements, Phase 2.
COMMITTEE ACTION: Received the list and provided input to staff.
7. Future Scheduled Meetinas
Monday, August 14, 2023 at 9:00 a.m.
Monday, September 11, 2023 at 9:00 a.m.
Monday, October 23, 2023 at 9:00 a.m.
8. Adjournment — at 11:18 a.m.
*Attachment: Presentation (Handout)
July 20, 2023 Regular Board Meeting Agenda Packet - Page 100 of 112