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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