Ali Sheikholeslami, P.E.
East Bay Municipal Utility District
CA-NV AWWA Conference, Rancho Mirage, CAOctober 23, 2018
Simultaneous Replacement of Two WTPs’ Obsolete Air-fed Ozone Systems
with Oxygen-fed Systems to Address Challenging T&O Issues
Accurate Project Budget
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Presentation Overview
• Overview of EBMUD and Sobrante and Upper San Leandro (USL) WTPs
• Project background and goal
• Project’s tasks responsibilities
• Scope, schedule, and cost
• Lessons learned
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East Bay Municipal Utility District
Service Area: San Francisco East Bay, 330 sq. miles
Water Customers: 1.4M
Water Source: Mokelumne River watershed (90%), Pardee & Camanche Reservoir, 5 local reservoirs
Water Treatment Plants: 5+1
Pressure Zones: 122
Pipes: 4,200 miles
Pumping Plants: 135
Distribution Reservoirs: 1644
East Bay Municipal Utility District
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Sobrante and USL WTPs –Conventional Plants with Ozone
Upper San Leandro
WTP
Sobrante WTP
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Treatment Process Schematic
Rapid Mix
Sedimentation Filtration
Anthracite/sand dual media
Cl
Intermediate Ozone
Contactor
Flocculation
Ammonia
Cl
Alum
+PolyOzone H2O2
Chlorine CT Disinfection
Aeration
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Sobrante and USL WTPs
• Design flow rates – Max. 60 MGD
• Seasonal WTPs – Out of service Nov.-Mar.
• Original ozone system installed 1991 for T&O o Three 750 lb/day air-fed ozone generators
o Ozone concentration 2.2% max.
o Max. ozone dose 3 mg/L
o Settled-water (intermediate) ozone contactor with diffuser system – HRT 11 min max. flow
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Original Ozone Air Fed System
Air Compressors Refrigerated Dryers Filters & Desiccant Dryers
GeneratorsCooling Water System
Air
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Original Ozone System Issues
• Lack of technical support
• High O&M costso System specific energy -15 kW-hr/lb O3
oAir-prep system maintenance
oUnreliable PSUs, control system
o Power harmonic issues at Sobrante WTP
• Limited ozone capacity to deal with major T&O events
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Sobrante WTP Raw Water Geosmin/MIB Data 2009-2015
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Sobrante & USL WTPs Ozone System Improvements Project
• Project goals
o Increase ozone capacity to deal with T&O
o Reduce O&M costs by increasing efficiency and reliability
o Reliable technical support
• Best alternative
o Install high-efficiency oxygen-fed generators
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Project’s Team
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• Design Consultant and Engineering Services during construction – Carollo Engineers
• Ozone System Supplier – Suez Treatment Technology
• General Contractor – Overaa Construction
• Construction PM – EBMUD, Brown & Caldwell
• Commissioning & Startup – EBMUD
• Control Systems Integration - EBMUD
Scope of Work at Sobrante WTP
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Scope of Work at USL WTP
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New Ozone Process Schematic
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LOX System
• Two 20,000 gallons LOX storage tanks, two vaporizers, associate piping, electrical and civil work
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Ozone Generation System
• Three 1750 lb/day ozone generators
• Maximum production 3500 ppd, 7.0 mg/L at 60 mgd @ 10%
• Power supply units (PSUs), master ozone controller panel
• Open and closed cooling water systems
• Supplemental nitrogen
• Ozone system piping, electrical/controls cable & conduit
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Ozone Generation Building Modifications
• New fire rated separation walls
• New floors
• MCCs
• HVAC
• Fire alarms & sprinkler system
• Emergency generators
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Ozone Generation System
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Ozone Contactors Modifications
• New ozone contactor slide gates with electrical actuators
• New diffuser system
• Exterior seal for contactors
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Ozone Destruct Modifications
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Hydrogen Peroxide System
• One 6,000-gal. aluminum storage tank
• Secondary containment
• 5 metering pumps with carry water
• Double contained HDPE buried piping
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Hydrogen Peroxide System
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Ozone Control System Block Diagram
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Ozone Generator Control Panels
Ozone Destruct
LOX PLC
Master Ozone Control Panel
To DCS
Auxiliary Equipment
Existing Control System
• PLCs and Moore controllers
• SCADA and operator interfaces
• Limited support and programming knowledge
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New Honeywell Experion Distributed Control System (DCS)
• Install servers & software
• Install fiber optics cable and conduits
• Program & build screens
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Overall Project Schedule
• Planning Phase – 2014
• Design Phase – May 2015 to Jan. 2017
• Ozone Equipment o Board contract award – May 2016
o Final ozone system submittals – June 2017
o Ozone equipment delivery – Nov./Dec. 2017
• Construction Phase o Board contract award – April, 2017
o Notice to Proceed – June 1, 2017
o Sobrante WTP Ready for Service – June 1, 18 ( rev. to July 1, 2018)
o USL WTP Ready for Service – July 1, 18 (rev. to Aug. 1, 2018)
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Sobrante WTP Schedule Challenge
• Sobrante WTP Ozone Ready-for-Service date slipped by six weeks
oMCC refurbishing
oAuxiliary systems HVAC, fire alarms, instrumentation
oCoordination between MOCP and auxiliary system programing
• District installed a temporary PAC feed system to deal with potential T&O events
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Project Cost
Phase Description Cost in $M
Design Design Consultant $3.4
District $1.2
Total Design $4.6
Construction Contract $34
Ozone Equipment $5.5
CM, Design Consultant (training, O&M, SOPs)
$5.1
DCS Control System (hardware, software, programming)
$2
District O&M Support, Training, etc. $1.3
Total Construction $47.9
Total $52.5
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Project Success
• Pre-purchase of ozone system equipment and assign it to contractor
• Good teamwork under tremendous pressure
• Negotiated addition of a second electrical subcontractor
• No recordable incidents
• Sobrante is producing water and ozone system is performing as designed
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Lessons Learned
• Have more stringent QA/QC process to review design drawings and specifications
• Do not construct two major WTPs projects concurrently
• Do not underestimate difficulty of treatment plan rehab work
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• Pay attention to the auxiliary systems
• Streamline fabrication witness process
• A new MCC may have been faster and easier than refurbishing an old MCC
• Plan for operation without ozone (powdered activated carbon)
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Lessons Learned
Acknowledgment
• EBMUD Project Team
• CM - Jimi Yoloye, Tim Karlstrand, Chris Shumate, Brett Margosian, Alisa Askins, Karl Tingwald, Joseph Patton, Ray N. Vanover, Joseph K. Kacyra, Samuel Abraham, Joseph Patton, Norm Settle (B&C), Carlos Garcia(B&C)
• O&M - Daniel Gill, Bryan Miller, Danielle Roybal-Alviz, Davis Gluchowaski, Ted Lam, Lisa Toth
• Engineering - Serge Terentieff, Michael Hartlaub, Alex Borys, Besnik Miftari, Hsini Wu, Chris Farajian, Jakira Jekayinfa-Brown, Justin Young, Angela Curtis, Noorun Nahar, Mykel Morgan
• Carollo Engineers Project Team – Chris Cleveland, Scott Weddle, Ashritha Banapuram, Ron Joost,
• Overaa Team - Jeff Naff, Mike Childs, Leah King, Bill Price, Mark Hunter, Malynda Lestrange, Danny Holdren, Michael Bailey
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Questions?
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