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    AgendaMonterey Peninsula Regional Water Authority (MPRWA)

    Technical Advisory Committee (TAC)Special Meeting

    1:00 PM, Tuesday, November 13, 2012Council ChamberFew Memorial Hall of Records

    Monterey, California

    CALL TO ORDER

    ROLL CALL

    PLEDGE OF ALLEGIANCE

    PUBLIC COMMENTS

    PUBLIC COMMENTS allows you, the public, to speak for a maximum of three minutes on anysubject which is within the jurisdiction of the MPRWA TAC and which is not on the agenda. Anyperson or group desiring to bring an item to the attention of the Committee may do so byaddressing the Committee during Public Comments or by addressing a letter of explanation to:MPRWA TAC, Attn: Monterey City Clerk, 580 Pacific St, Monterey, CA 93940. The appropriatestaff person will contact the sender concerning the details.

    AGENDA ITEMS

    1. Receive and Discuss Consultants Report from Separation Processes Inc.: Evaluation ofSeawater Desalination Projects and Make Recommendations to the MPRWA AuthorityDirectors

    ADJOURNMENT

    The Monterey Peninsula Regional Water Authority is committed to include the disabled in all ofits services, programs and activities. For disabled access, dial 711 to use the California RelayService (CRS) to speak to staff at the Monterey City Clerks Office, the Principal Office of theAuthority. CRS offers free text-to-speech, speech-to-speech, and Spanish-language services24 hours a day, 7 days a week. If you require a hearing amplification device to attend ameeting, dial 711 to use CRS to talk to staff at the Monterey City Clerks Office at(831) 646-3935 to coordinate use of a device or for information on an agenda.

    Agenda related writings or documents provided to the MPRWA are available for publicinspection during the meeting or may be requested from the Monterey City Clerks Office at 580Pacific St, Room 6, Monterey, CA 93940. This agenda is posted in compliance with CaliforniaGovernment Code Section 54954.2(a) or Section 54956.

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    Prepared For:Monterey Pen insu la Reg iona l Water Au t hor i ty

    Evaluation of Seawater DesalinationProjects

    November 2012 DRAFT REPOR

    Preparedb

    SeparationProcesses,I

    3156LionsheadA

    Suit

    Carlsbad,CA 920

    760400

    36

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    MONTEREY PENINSULA REGIONAL WATER AUTHORITY TABLE OF CONTENTS

    Page i

    CONTENTS

    EXECUTIVESUMMARY.......................................................................................................................................1

    PROJECTSUMMARIES...............................................................................................................................................1

    PROJECTFUNCTION..................................................................................................................................................2

    PROJECTPERFORMANCE..........................................................................................................................................4

    ECONOMICS..............................................................................................................................................................5

    IMPLEMENTATIONCONSIDERATIONS......................................................................................................................7

    1 INTRODUCTION......................................................................................................................................11

    2 PROJECTSUMMARIES............................................................................................................................21

    2.1

    CALIFORNIAAMERICANWATER(CALAM)

    ............................................................................................................

    22

    2.2 DEEPWATERDESAL(DWD)..............................................................................................................................24

    2.3 PEOPLESMOSSLANDING(PML).........................................................................................................................26

    3 PROJECTFUNCTION...............................................................................................................................31

    3.1 CALIFORNIAAMERICANWATER(CALAM)............................................................................................................31

    3.1.1 ProjectPurpose..................................................................................................................................31

    3.1.2 CustomersIdentified..........................................................................................................................31

    3.1.3 AdequacyofTreatmentApproach.....................................................................................................31

    3.1.4 ResidualsHandling.............................................................................................................................34

    3.1.5 FeedWaterCharacterization.............................................................................................................34

    3.1.6 QualityofProjectInformation...........................................................................................................34

    3.1.7

    Omissions

    or

    Fatal

    Flaws

    ...................................................................................................................

    3

    5

    3.2 DEEPWATERDESAL(DWD)..............................................................................................................................35

    3.2.1 ProjectPurpose..................................................................................................................................35

    3.2.2 CustomersIdentified..........................................................................................................................36

    3.2.3 AdequacyofTreatmentApproach.....................................................................................................36

    3.2.4 ResidualsHandling.............................................................................................................................38

    3.2.5 FeedWaterCharacterization.............................................................................................................38

    3.2.6 QualityofProjectInformation...........................................................................................................38

    3.2.7 OmissionsorFatalFlaws...................................................................................................................39

    3.3 PEOPLESMOSSLANDING(PML)........................................................................................................................39

    3.3.1 ProjectPurpose..................................................................................................................................39

    3.3.2 CustomersIdentified..........................................................................................................................39

    3.3.3 AdequacyofTreatmentApproach.....................................................................................................39

    3.3.4

    ResidualsHandling

    ...........................................................................................................................

    311

    3.3.5 FeedWaterCharacterization...........................................................................................................312

    3.3.6 QualityofProjectInformation.........................................................................................................312

    3.3.7 OmissionsorFatalFlaws.................................................................................................................312

    4 PROJECTEDPERFORMANCE....................................................................................................................41

    4.1 CALIFORNIAAMERICANWATER(CALAM)............................................................................................................41

    4.1.1 PlantDesignCapacity........................................................................................................................41

    4.1.2 TargetedProductWaterQuality........................................................................................................42

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    INTRODUCTION MONTEREY PENINSULA REGIONAL WATER AUTHORITY

    Page ii

    4.1.3 DisinfectionStrategy..........................................................................................................................43

    4.2 DEEPWATERDESAL(DWD)..............................................................................................................................44

    4.2.1 PlantDesignCapacity........................................................................................................................44

    4.2.2 TargetedProductWaterQuality........................................................................................................44

    4.2.3 DisinfectionStrategy..........................................................................................................................45

    4.3 PEOPLESMOSSLANDING(PML).........................................................................................................................45

    4.3.1

    PlantDesign

    Capacity

    ........................................................................................................................

    454.3.2 TargetedProductWaterQuality........................................................................................................45

    4.3.3 DisinfectionStrategy..........................................................................................................................46

    5 ECONOMICS...........................................................................................................................................51

    5.1 CALIFORNIAAMERICANWATER(CALAM)...........................................................................................................55

    5.2 DEEPWATERDESAL(DWD)..............................................................................................................................57

    5.3 PEOPLESMOSSLANDING(PML).........................................................................................................................59

    6 IMPLEMENTATIONCONSIDERATIONS.....................................................................................................61

    6.1 CALIFORNIAAMERICANWATER(CALAM)............................................................................................................62

    6.2 DEEPWATERDESAL(DWD)..............................................................................................................................65

    6.3 PEOPLESMOSSLANDING(PML).........................................................................................................................67

    6.3.1Assessment

    of

    Impacts

    of

    Seawater

    Intake

    .......................................................................................

    67

    6.3.2 BrineDischarge..................................................................................................................................68

    7 REFERENCES...........................................................................................................................................71

    LIST OF TABLES

    TABLEES1SUMMARYOFPROPOSEDPRODUCTWATERQUALITY.......................................................................................ES4

    TABLEES2SUMMARYOFEVALUATEDCAPITALANDOPERATINGCOSTESTIMATES..................................................................ES6

    TABLE41SUMMARYOFPROJECTEDPRODUCTQUALITYFROMCALAMFACILITY...................................................................43

    TABLE42SUMMARYOFPROJECTEDPATHOGENCREDITSFORCALAMPROJECT....................................................................43

    TABLE43SUMMARYOFPROJECTEDPRODUCTQUALITYFROMDWDFACILITY......................................................................44

    TABLE44

    SUMMARYOFPROJECTEDPATHOGENCREDITSFORDWDPROJECT

    ........................................................................

    45

    TABLE45SUMMARYOFPROJECTEDPRODUCTQUALITYFROMPMLFACILITY1......................................................................46

    TABLE46SUMMARYOFPROJECTEDPATHOGENCREDITSFORPMLPROJECT.........................................................................46

    TABLE51SUMMARYOFCHEMICALUNITPRICES..............................................................................................................52

    TABLE52SUMMARYOFEVALUATEDCAPITALANDOPERATINGCOSTESTIMATES....................................................................54

    TABLE53SUMMARYOFCALAMCAPITALCOSTEVALUATION.............................................................................................55

    TABLE54SUMMARYOFCALAMO&MCOSTEVALUATION...............................................................................................56

    TABLE55SUMMARYOFDWDCAPITALCOSTEVALUATION................................................................................................57

    TABLE56SUMMARYOFDWDO&MCOSTEVALUATION..................................................................................................58

    TABLE57SUMMARYOFPMLCAPITALCOSTEVALUATION.................................................................................................59

    TABLE58SUMMARYOFPMLO&MCOSTEVALUATION.................................................................................................510

    LIST OF FIGURES

    FIGUREES1PROJECTEDCALAMPROJECTIMPLEMENTATIONSCHEDULE.............................................................................ES7

    FIGUREES2PROJECTEDDWDPROJECTIMPLEMENTATIONSCHEDULE................................................................................ES8

    FIGUREES3PROJECTEDPMLPROJECTIMPLEMENTATIONSCHEDULE..................................................................................ES8

    FIGURE21CALAMPROJECTLOCATIONMAP..................................................................................................................23

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    MONTEREY PENINSULA REGIONAL WATER AUTHORITY TABLE OF CONTENTS

    Page iii

    FIGURE22DWDPROJECTLOCATIONMAP.....................................................................................................................25

    FIGURE23PMLPROJECTLOCATIONMAP......................................................................................................................27

    FIGURE61CONCEPTUALIMPLEMENTATIONSCHEDULEFORTHECALAMPROJECT..................................................................65

    FIGURE62CONCEPTUALIMPLEMENTATIONSCHEDULEFORTHEDWDPROJECT.....................................................................66

    FIGURE63CONCEPTUALIMPLEMENTATIONSCHEDULEFORTHEPMLPROJECT.........................................................................68

    ABBREVIATIONS AND ACRONYMS

    AACE Association for the Advancement of Cost Engineering

    AF Acre-Foot

    AFY Acre-Feet/Year

    ASR Aquifer Storage and Recovery

    Cal-Am California American Water

    CDPH California Department of Public HealthCEQA California Environmental Quality Act

    CPCN - Certificate of Public Convenience and Necessity

    CPUC California Public Utilities Commission

    Crypto - Cryptosporidium

    CSIP Castroville Seawater Intrusion Project

    DWD DeepWater Desal

    EA Environmental Assessment

    EIR Environmental Impact Report

    EIS Environmental Impact Statement

    EPA U.S. Environmental Protection Agency

    ERD Energy Recovery Device

    fps feet per second

    FPVC Fusible Polyvinyl Chloride\

    gfd Gallons per Day per Square Foot

    GWR Groundwater Replenishment

    HDPE High Density Polyethylene

    KHC Kris Helm Consulting

    lb - pound

    LF Lineal Foot

    MCL Maximum Contaminant Level

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    INTRODUCTION MONTEREY PENINSULA REGIONAL WATER AUTHORITY

    Page iv

    MPRWA Monterey Peninsula Regional Water Authority

    MRWPCA Monterey Regional Water Pollution Control Agency

    mgd Million Gallons per Day

    MF Microfiltration

    MG Million Gallons

    MLCP Moss Landing Commercial Park

    MLPP Moss Landing Power Plant

    MPWSP Monterey Peninsula Water Supply Project

    NEPA National Environmental Policy Act

    NOD Notice of Determination

    NOI Notice of Intent

    NOAA National Oceanic and Atmospheric Administration

    NPDES National Pollutant Discharge Elimination System

    O&M Operations and Maintenance

    PG&E Pacific Gas and Electric

    PML Peoples Moss Landing

    RO Reverse Osmosis

    SCADA Supervisory Control and Data Acquisition

    SDI Silt Density Index

    SPI Separation Processes Inc.SVGB Salinas Valley Groundwater Basin

    SWRCB State Water Resources Control Board

    SWTR Surface Water Treatment Rule

    TAC Technical Advisory Committee

    TBD To Be Determined

    TDS Total Dissolved Solids

    TOC Total Organic Carbon

    UF - Ultrafiltration

    UV Ultra Violet Light

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    MONTEREY PENINSULA REGIONAL WATER AUTHORITY EXECUTIVE SUMMARY

    Page ES-1

    Separation Processes Inc. (SPI) in association with Kris Helm Consulting (KHC) is providingengineering and consulting support to the Monterey Peninsula Regional Water Authority(MPWRA) to assist with the evaluation of three candidate desalination projects on the MontereyPeninsula. This report presents the results of our evaluation of the projects, targeted at replacing

    supplies currently extracted from the Carmel River but subject to a 1995 order from the StateWater Resources Control board to secure an alternate source of supply by December, 2016.

    The proposed strategy for meeting the projected annual demand within the California AmericanWater service area of 15,250 acre-feet is a multi-pronged approach including permittedextractions from the Carmel River and Seaside Basin, an aquifer-storage and recovery system,and the existing Sand City desalination plant--totaling 6,250 acre-feet; leaving a 9,000 acre-feetgap in supply. Two alternatives are under consideration to compose this final supplya 9,000acre-feet production seawater desalination plant; or a 5,500 acre-feet seawater desalination plantin concert with a groundwater water replenishment project using advanced treated recycled waterof 3,500 acre-feet.

    This report presents the results of our evaluation of three candidate alternatives for the seawaterdesalination component of the overall water supply portfolio. California American Water isactively engaged with the California Public Utilities Commission to build a facility and securethe required supply. Two other development groups have proposed alternative projects forconsiderationDeepWater Desal, LLC and the Peoples Moss Landing Water Desal Project.The three projects were analyzed on functional, performance, economic and implementationgrounds in an effort to provide a balanced evaluation for consideration by the MPRWA.

    The three projects are in the conceptual or preliminary stage of development and all three have astheir objective to provide California American Water the seawater desal component of the

    required replacement water supply under State Water Resources Control Board Order No. 95-10.The DeepWater Desal group proposes to provide an expandable plant capable of servingadditional regional water needs as well, outside of the California American Water service area.Brief summaries of the projects follow:

    Project Name Monterey Peninsula Water Supply Project(MPWSP)

    Proponent(s) California American Water (Cal-Am)

    Location 46-acre site of vacant, disturbed land west of theMRWPCA Regional Treatment Plant (RTP).

    Purpose To supply supplemental desal component of theMonterey Peninsula regional water supply

    This project is currently under consideration by theCalifornia Public Utilities Commission (CPUC).

    Production Volume 5.4 mgd or 9.0 mgd

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    INTRODUCTION MONTEREY PENINSULA REGIONAL WATER AUTHORITY

    Page ES-2

    Project Name DeepWater Desal (DWD)

    Proponent(s) DeepWater Desal, LLC, Dynegy Moss LandingPower Plant, MFJK Partnership of the CapurroRanch, PV2 Solar, and Ecomert Technologies

    Location Capurro Ranch Property, north of /Elkhorn SloughPurpose Phase 1 to supply supplemental desal component of

    the Monterey Peninsula regional water supply

    Phase 2 to supply northern customers

    Production Volume Phase 1: 4.9 mgd or 9.1 mgd

    Phase 2: 22.0 mgd

    Project Name The Peoples Moss Landing Water Desal Project(PML)

    Proponent(s) DeSal America, LLC composed of Moss LandingCommercial Park, LLC; and Stanley and Patricia-Vance Lueck

    Location Moss Landing Commercial Park

    Purpose To supply supplemental desal component of theMonterey Peninsula regional water supply

    This project is currently proposed as alternative tothe Cal-Am MPWSP.

    Production Volume 4.8 mgd or 9.4 mgd

    We evaluated the function of each project in terms of project purpose, customers identified,adequacy of treatment approach, residuals handling, feed water characterization, quality ofproject information, and any omissions or fatal flaws in the information provided. Theevaluation was conducted based on information provided in response to a 56-item questionnaireprepared by the MPRWA technical advisory committee and submitted by each proponent; alongwith additional information each provided in response to specific questions and interviews fromSPI and KHC.

    All three projects have available sites for building the required treatment facilities; and credibleseawater intake and brine disposal approaches, though there are substantive differences amongthem. Cal-Am proposes to use a group of subsurface slant intake wells (up to eight for themaximum capacity plant alternative); DWD proposes a new screened open ocean intake installedat roughly 60-ft of depth; and PML is considering options to use either an existing seawaterintake pump station drawing from the Moss Landing Harbor, or potentially a new screened openocean intake installed coincident with an existing 51-in diameter concrete outfall pipeline owned

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    MONTEREY PENINSULA REGIONAL WATER AUTHORITY EXECUTIVE SUMMARY

    Page ES-3

    by the Moss Landing Commercial Park. Cal-Am has projected there may up to 3 percent ofgroundwater from the Salinas Valley Groundwater Basin (SVGB) entrained with their intakesupply that would need to be returned (as facility product water) to the basin. For brine disposal,Cal-Am and DWD propose to blend concentrated brine from the desal plants with existingoutfall flowsCal-Am blending with the existing Monterey Peninsula Regional Water Pollution

    Control Agencys wastewater plant outfall; and DWD using the existing cooling water returnoutfall at the Moss Landing Power Plant. Both sources have sufficient dilution and hydrauliccapacities. PML proposes to use their existing 51-in diameter outfall, currently permitted todischarge magnesium-depleted seawater. There is some evidence of disrepair of the outfall interms of pipeline integrity and condition of the existing diffusers which would need to beaddressed along with the permitting of a non-shore diluted brine stream.

    Cal-Am and PML propose to serve only the identified demand within the Cal-Am service area atthe two plant capacity increments under consideration; while DWD envisions a higher capacityregional project, capable of producing up to 25,000 AFY. DWD has not yet secured agreementswith any potential customers.

    In terms of treatment approachall three candidate teams propose to use reverse osmosis (RO)as the primary desalination technology. However, both DWD and PML propose a single passRO system; while Cal-Am has proposed a partial double or two pass systemtreating a portionof the product water from the first pass RO system with a second RO system and blending thesupplies to form the final treated water. The issue relates to the quality of product waterproduced, more than treatment function; as either approach is considered functional.

    Pre- and post-treatment approaches are similar. All incorporate granular media filtration of theincoming seawater, with PML following on with a low pressure membrane filtration system(microfiltration or ultrafiltration) to deal with the anticipated higher solids load from waterextracted from Moss Landing Harbor. In the case of Cal-Am, the aquifer filtration provided bythe slant wells could obviate the need for media filtration; but the potential presence of iron and

    manganese in the supply could just as well make them necessaryso the approach is consideredconservative. In the case of DWD, the incoming seawater extracted at depth will be cold(roughly 15 C) and warmed through a proprietary warming system at the Moss Landing PowerPlant prior to transmission to the treatment plant site. All three proponents propose to use calcitebeds, carbon dioxide and sodium hydroxide for re-mineralization/stabilization of the RO treatedproduct water and chlorine disinfection.

    Cal-Am and DWD will require offsite pipelines for feed, product water and brine disposal; whilePML proposes to use existing intake and outfall pipelines originating on site; requiring only aproduct water delivery pipeline. DWDs site location north of the Elkhorn Slough is likely toentail complex issues with crossings for all three of their large diameter pipelines (one 48-in andtwo 36-in).

    All three proponents were cooperative with our evaluation and provided all available andrequested information. The Cal-Am project through past work on other regional projects as wellas ongoing procedures with the California Public Utilities Commission has produced the mostdetailed information on their project, followed by DWD who have prepared a fair amount ofpredesign data on their proposed system along with active environmental investigations for theirproposed intake. PML is at a more preliminary level of engineering and planning in comparison.

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    INTRODUCTION MONTEREY PENINSULA REGIONAL WATER AUTHORITY

    Page ES-4

    Importantly however, we have not found any fatal flaws associated with any of the candidateprojects.

    Performance of each proposed system was gauged relative to categories of plant design capacity,targeted product water quality and disinfection strategy.

    For plant capacity, we considered the proposed instantaneous design capacity of each treatmentfacility in comparison to the required annual production incrementeither 5,500 AFY or 9,000AFY. What we found were wide variationswith Cal-Am proposing capacities of 5.4 mgd and9.0 mgd; DWD of 4.9 mgd and 9.1 mgd; and PML at 4.8 mgd and 9.4 mgd. We considered thelevel of equipment redundancy proposed by each team in the context of the amount of onlinetime it would require a facility at a given rated capacity to deliver the required annual allotment.For Cal-Am, we gauged their planned design capacities adequate considering the need to returnflow to the SVGB as well as meet the 5,500 AFY or 9,000 AFY into their distribution system.At capacities of 5.4 mgd and 9.0 mgd, the plant(s) would need to operate 98 percent of the time

    to meet productionnot overly conservative but achievable given the level of equipmentredundancy (including spare process units) in their proposed facility. DWD, with similarproposed levels of redundancy, would have equivalent minimum facility capacity requirementsof 5.0 mgd and 8.2 mgd; somewhat lower than Cal-Am as they lack the requirement to returnflow to the SVGB. PML did not provide a detailed equipment list indicating numbers of processunits; so gauging proposed levels of equipment redundancy was uncertain. However, we feel thefacility should have adequate reliability and conducted our evaluation on that basisrecommending equivalent capacity ratings to DWD of 5.0 mgd and 8.2 mgd.

    The product quality produced by the proposed systems would differ based on the configurationof their proposed RO systems. Cal-Ams proposed partial two-pass system could likely achievechloride, boron, and total dissolved solids (TDS) consistent with current Carmel River supplies;

    but the single pass systems would not. We consider a lower salinity product supply an asset andevaluated all three projects (from an economic perspective) as having partial two-pass ROsystems. The recommended product quality goal is summarized in Table ES-1.

    Table ES-1 Summary of Proposed Product Water Quality

    Total Dissolved Solids mg/L 380

    Chloride mg/L 60

    Boron mg/L 0.5

    pH units 8.0

    Calcium mg/L as CaCO3 40

    Alkalinity mg/L as CaCO3 40

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    MONTEREY PENINSULA REGIONAL WATER AUTHORITY EXECUTIVE SUMMARY

    Page ES-5

    For disinfection, the proposed facilities must comply with the Surface Water Treatment Rule andLong-Term 2 Enhanced Surface Water Treatment Rule. Under these regulations, pathogenremoval/inactivation requirements are set on a logarithmic (log) scale, with the CaliforniaDepartment of Public Health establishing specific log removal for priority pathogens, includinggiardia, cryptosporidium (crypto), and virus. The levels set will be based on source water quality

    and other factors, and are expected to be in the range of 3-5 for giardia, 2-4 for crypto, and 4-6for virus, based on each of the project source waters being classified as surface waters or underthe influence of surface waters. We find all three projects are likely to achieve sufficient logremoval credits under their proposed treatment schemes to comply.

    A primary focus of our evaluation was to provide a balanced, apples to apples comparison ofthe candidate projects from an economic perspective. We implemented this by focusing on thefollowing principles:

    Uniformity in plant design capacity for the two non-regional approaches; equivalentcapacity allocation for the proposed DWD regional project.

    Equivalency in treatment to achieve: a common RO feed water quality followingpretreatment; a common treated water quality goal; and pathogen removal creditsrequired for the applicable supply source.

    Uniformity in equipment redundancy. Uniformity in unit cost criteria for common items. Uniformity in cost factors applied to aggregated costs (e.g., contingencies; electrical

    and I&C costs; etc.).

    Uniformity in unit costs for chemicals and other consumables for treatmentevaluations.

    To implement the above, we adjusted plant capacities for the evaluation on the basis described inthe Project Performance discussion, rating Cal-Ams proposed system at design capacities of 5.4mgd and 9.0 mgd; and the DWD and PML systems at 5.0 mgd and 8.2 mgd. In terms oftreatment process, we attempted to maintain the overall proposed process design of theproponents, but did evaluate all as including a partial (40 percent) capacity second pass ROsystem. We also assumed N+1 redundancy on all rotating equipment and major treatmentprocess units (e.g., filters, RO membrane trains). We employed an equivalent basis indeveloping our capital equipment cost estimates, relying on targeted quotes for equipment andSPIs cost information from past, similar seawater RO projects. For indirect costs, we assumed

    fixed factors and applied them uniformly to each project.We implemented a similar strategy on annual operating and maintenance expenses, usingcommon chemical unit prices along with pricing on common consumables, such as the ROprocess membranes. The results of our evaluation are presented in Table ES-2.

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    INTRODUCTION MONTEREY PENINSULA REGIONAL WATER AUTHORITY

    Page ES-6

    Table ES-2 - Summary of Evaluated Capital and Operating Cost Estimates

    Intake/Outfall $37.0 $31.7 $2.71 $1.66 $3.00 $3.00

    Pretreatment & Residuals Handling $10.6 $7.94 $11.2 $7.94 $20.2 $13.6

    Desalination System $22.3 $15.1 $19.4 $13.2 $19.9 $14.0

    Post-Treatment $1.48 $0.88 $1.48 $0.88 $1.66 $1.07

    Distribution $17.0 $16.0 $29.0 $28.9 $22.4 $22.3

    Site Structures $11.5 $10.8 $3.65 $2.52 $10.0 $7.00

    Indirect Costs1 $58.0 $50.8 $54.5 $47.5 $67.9 $62.3

    Contingency Allowance (30%) $47.4 $40.0 $36.6 $30.8 $43.6 $37.0

    Mitigation Allowance (1%) $1.60 $1.30 $1.20 $1.00 $1.50 $1.20

    Energy $5.83 $3.54 $3.93 $2.41 $4.20 $2.56

    Chemicals $0.32 $0.19 $0.83 $0.50 $0.93 $0.57

    Expendables $0.69 $0.45 $1.02 $0.68 $1.09 $0.65

    Other Proponent Expenses -- -- $2.85 $2.60 -- --

    O&M Labor $2.69 $2.36 $2.69 $2.36 $2.69 $2.36

    Equipment Replacement2 $1.50 $1.23 $1.01 $0.83 $1.16 $0.92

    Capital Recovery3 $12.0 $10.1 $9.24 $7.77 $11.0 $9.34

    Total Annual Cost $23.0 $17.9 $21.5 $17.2 $21.1 $16.4

    1Includes implementation costs at 25%; ROW easement and land costs, mobilization/demobilization at 2%; electrical and I&C systems at 18%; engineering

    and startup at 15%; and additional project proponent prescribed costs. All percentages applied to plant facilities costs.2 Calculated as 1.5% of plant facilities costs.3 Capital recovery factor based on an interest rate of 4.0% and term of 30 years.

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    MONTEREY PENINSULA REGIONAL WATER AUTHORITY EXECUTIVE SUMMARY

    Page ES-7

    Overall, the final water production costs are fairly equivalent given the overall accuracy of theestimate and degree of project development. Cal-Ams capital cost is the highest; owing largelyto its high intake system cost. PML is proposing to reuse existing intake infrastructure; whileDWD has an unspecified separate business entity which will be funding its intake, outside of theassigned DWD facility budget. Cal-Ams operating cost is also relatively high, owing in large

    measure to higher stipulated energy costs than either DWD or PMLroughly $0.13/kW-hr vs.$0.08 kW-hr.

    The three projects are at varying states of development in terms of the regulatory permittingprocess. Cal-Am is further along than either DWD or PML, though DWD has completed or isnearing completion of their initial CEQA compliance documents. Forecast projectimplementation schedules were identified for each project proponent, based on a select numberof key environmental and permitting tasks, including:

    1. A project description must be completed.2. An Environmental Assessment must be made.3. An EIR/EIS must be completed (CEQA/NEPA compliance).4. Commercial Agreements must be negotiated/ Cal-Am must obtain a Certificate of Public

    Convenience and Necessity (CPCN), after certification of the EIR.

    5. Jurisdictional Permits must be obtained for facilities impacting Waters of the U.S.6. NPDES Permits must be amended/obtained.7. Coastal Development Permits must be obtained.

    It was further assumed that each proponent had the financial capacity to proceed with predesign

    preparation/procurement package development such that the project could be put out to finaldesign and construction bid coincident with approval of the final project permits. The schedulesare provided below as Figure ES-1, Figure ES-2 and Figure ES-3.

    Figure ES-1 Projected Cal-Am Project Implementation Schedule

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    INTRODUCTION MONTEREY PENINSULA REGIONAL WATER AUTHORITY

    Page ES-8

    Figure ES-2 Projected DWD Project Implementation Schedule

    Figure ES-3 Projected PML Project Implementation Schedule

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    MONTEREY PENINSULA REGIONAL WATER AUTHORITY INTRODUCTION

    Page 1-1

    1 INTRODUCTIONSeparation Processes Inc. (SPI) and Kris Helm Consulting (KHC) are providing engineering andconsulting support to the Monterey Peninsula Regional Water Authority (MPWRA) to assistwith the evaluation of three candidate desalination projects on the Monterey Peninsula. SPI

    conducted technical and economic evaluations of the proposed projects; while KHC examinedissues relating to permitting and environmental compliance.

    California American Water (Cal-Am) is an investor owned public utility who is responsible forproviding the water supply to cities covered within the MPRWACarmel-by-the-Sea, Del ReyOaks, Monterey, Pacific Grove, Sand City and Seaside. The proposed projects wouldsupplement supply previously extracted for the region from the Carmel River. In 1995, the StateWater Resources Control Board (SWRCB) in its Order No 95-10 found that Cal-Am waswithdrawing water from a subterranean stream, rather than percolating groundwater; and in theprocess extracting an average of 10,730 AFY in access of its valid right of 3,376 AFY. Theorder required Cal-Am to secure a replacement source of supply by December 2016.

    The average annual water demand in the region is 15,250 AFY1. Currently identified sourcesinclude established rights to Carmel River and Seaside Basin waters of 4,850 AFY, the aquiferstorage and recovery (ASR) system of 1,300 AFY, and 94 AFY from the Sand City DesalinationPlant. This leaves a roughly 9,000 AFY deficit to be made up. Alternatives include a new 9,000AFY seawater desalination plant; and a new groundwater replenishment (GWR) project of 3,500AFY in combination with a new 5,500 AFY seawater desalination plant.

    The technical advisory committee (TAC) of the MPRWA developed a list of 56 questions tosubmit to the three desalination project proponents, including Cal-Am, DeepWater Desal, LLC(DWD) and the Peoples Moss Landing Desal (PML). Each proponent is proposing to build adesalination facility to satisfy the planned desalination component of the regional water supply.Responses and supporting information were received from each, exhibiting various stages ofdevelopment and differences in approach. The differences were such that a deliberative, faircomparative evaluation could not be conducted solely on the basis of the information provided.

    This report presents the results of a more detailed evaluation and analysis conducted by SPI andKHC. The work was conducted based on information provided in the original responses to thequestions from the TAC along with supplemental information provided by each proponent. Thegoal was to provide an apples-to-apples comparison of each project on an equivalent costbasis; along with an evaluation of the realistic implementation schedule for each, taking intoaccount environmental and permitting issues.

    1 RBF Memorandum, Recommended Capacity for the Monterey Peninsula Water Supply Project (MPWSP)Desalination Plant, April 20, 2012

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    The tabular summaries provided in this section include information on each of the proponent

    projects, including:

    Project name Proponent(s) Location Purpose Production volume Key features Facility map Key information provided to review team Persons interviewed/corresponded with

    The TAC requested information from each proponent that would satisfy the desalinationcomponent of the proposed water supply. Responses received from the Cal-Am and PMLgroups were generally in line with this request; though there were slight differences in theproposed plant capacities. The DWD response proposed to only serve the higher 9,000 AFYrequirement, along with a planned expansion to act as a regional water supply source to otheragencies on the peninsula as well as cities north of Moss Landing. DWD did reveal in responseto subsequent inquiries how they would serve the 5,500 AFY supply scenario. The information

    presented for each project represents their current status from the proponents at the time of thisreport writing.

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    PROJECT SUMMARIES MONTEREY PENINSULA REGIONAL WATER AUTHORITY

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    Project Name Monterey Peninsula Water Supply Project

    (MPWSP)

    Proponent(s) California American Water

    Location 46-acre site of vacant, disturbed land west of theMRWPCA Regional Treatment Plant (RTP).

    Purpose To supply supplemental desal component of theMonterey Peninsula regional water supply

    This project is currently under consideration by theCalifornia Public Utilities Commission (CPUC).

    Production Volume 5.4 mgd or 9.0 mgd

    Key Features 1.Raw seawater supply through a series of up toeight sub-surface slant wells located on a vacant

    376 acre parcel with roughly 7,000 feet of oceanshoreline.2.Raw water and pump to waste transmission

    through one of eight candidate alignments.3.Single-stage, dual media pressure filtration

    pretreatment.4.Partial 2-pass RO desalination treatment with

    energy recovery. Final product has a proposedblend of 60:40 first pass:second pass product.

    5.Product stabilization with calcite, carbon dioxide,and sodium hydroxide.

    6.Disinfection with sodium hypochlorite andtemporary UV.

    7.2 x 1.0 MG product storage tanks, productdistribution pumps, and 36-in diameter productpipeline to Cal-Am distribution system nearSeaside.

    8.24-in brine disposal pipeline to the existing RTPoutfall.

    Key Information Provided 1.TAC response package2.Response to supplemental questions from SPI

    and KHC

    3.Relevant testimony to the CPUC4.RBF 2011 memo on implementation schedule

    risk of regional supply alternatives5.RFB 2011 memo on cost analysis of regional

    supply alternatives

    Persons Interviewed/Corresponded With Richard Svindland

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    Figure 2-1 Cal-Am Project Location Map

    ____Slant Well

    ____ Intake

    ____ Brine

    ____ Product Water

    Desalination Plant

    Tie-in to CAL AMexisting facilities

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    Project Name DeepWater Desal

    Proponent(s) DeepWater Desal, LLC, Dynegy Moss LandingPower Plant, MFJK Partnership of the CapurroRanch, PV2 Solar, and Ecomert Technologies

    Location Capurro Ranch Property, north of /Elkhorn Slough

    Purpose Phase 1 to supply supplemental desal component ofthe Monterey Peninsula regional water supply

    Phase 2 to supply northern customers

    Production Volume Phase 1: 4.9 mgd or 9.1 mgd

    Phase 2: 22.0 mgd

    Key Features 1. Raw seawater supply through a new 48-in openintake extending into the Monterey Bay west of

    Moss Landing at a depth of roughly 65-ft.2. Raw water transmission through an existing

    right of way maintained by MLPP to an existingpump station at MLPP for transfer to the site.

    3. Proprietary warming system at MLPP whichwill increase the temperature of the raw water.

    4. Transmission of the warmed feed water througha new 36-in pipeline to the Capurro Ranch site.

    5. Single-stage, dual media pressure filtrationpretreatment.

    6. Single-pass RO desalination treatment with

    energy recovery.7. Product stabilization with calcite, carbon

    dioxide, and corrosion inhibitor.8. Disinfection with sodium hypochlorite.9. 2.5 MG product storage tank, product

    distribution pumps, and 30-in diameter productpipeline to Cal-Am distribution system nearSeaside.

    10.36-in brine disposal pipeline to MLPP existingcooling water ocean discharge.

    Key Information Provided 1.TAC response package2.Response to supplemental questions from SPI

    and KHC3.Tenera Environmental, Preliminary Modeling of

    Potential Impacts from Operation of aDesalination Facility Ocean Intake, August 22,2012

    Persons Interviewed/Corresponded With Dennis Ing, Scott Jackson, Jonathan Dietrich

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    Figure 2-2 DWD Project Location Map

    ____Intake

    ____ Brine

    ____ Product Water

    Desalination Plant

    Tie-in to CAL AMexisting facilities

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    Project Name The Peoples Moss Landing Water Desal Project

    Proponent(s) DeSal America, LLC composed of Moss LandingCommercial Park, LLC; and Stanley and Patricia-Vance Lueck

    Location Moss Landing Commercial Park

    Purpose To supply supplemental desal component of theMonterey Peninsula regional water supply

    This project is currently proposed as alternative tothe Cal-Am MPWSP.

    Production Volume 4.8 mgd or 9.4 mgd

    Key Features 1. Raw seawater supply through an existing intakesystem drawing from the Moss Landing Harbor.

    2.

    Single-stage, zeolite pressure filtration followedby ultrafiltration (UF) pretreatment.3. Single-pass RO desalination treatment with

    energy recovery.4. Product stabilization with calcite, carbon

    dioxide, and sodium hydroxide.5. Disinfection unspecified, but presumed to be

    with sodium hypochlorite.6. Product storage in existing site tankage. New

    distribution pump station and 36-in diameterproduct pipeline to Cal-Am distribution system

    near Seaside.7. Brine disposal through existing 51-in (internaldiameter) outfall.

    Key Information Provided 1.TAC response package2.Project information package dated July 20123.Response to supplemental questions from SPI

    and KHC4.Video of a portion of the existing outfall.5.August 2012 Structural Evaluation Report of site

    structures and outfall, conducted by JAMSEEngineering, Inc.

    6.Construction drawings for the outfall (1973) andmodifications made to the intake pump station(1968).

    7.September 2012 Environmental Issues andConstraints Report by SMB Environmental Inc.

    Persons Interviewed/Corresponded With Nader Agha, George Schroeder, Stanley Lueck

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    Figure 2-3 PML Project Location Map

    ____Intake

    ____ Brine

    ____ Product Water

    Desalination Plant

    Tie-in to CAL AMexistin facilities

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    The function of each proponent project is evaluated on the following criteria:

    Project purpose Customers identified Adequacy of treatment approach Residuals handling Feed water characterization Quality of project information Omissions or fatal flaws

    In an initial screening level evaluation2, we found no disqualifying criteria for any of thecandidate projects. We did however find differences in the level of project development andapproach. Each project is discussed separately below.

    3.1.1 Project PurposeCal-Am proposes their project to serve the needs of the identified demand on the MontereyPeninsula within their service area to comply with SWRCB Order 95-10. The proposedtreatment plant would serve the identified desalination component of the regional water supplyportfolio. They specifically do not propose to provide a plant capacity in excess of definedregional water supply requirements under two scenarioswith GWR and without GWR3.

    3.1.2 Customers IdentifiedTreated water would be supplied to the Cal-Water distribution system for service to its currentservice area. Any groundwater from Salinas Basin drawn through the proposed supply wellswould be returned the basin as plant treated water through the Castroville Seawater IntrusionProject (CSIP) ponds3.

    3.1.3 Adequacy of Treatment ApproachFeed water for the desalination plant would be extracted from subsurface slant wells. Over the

    long term, feed water is projected to include about 97 percent seawater and 3 percent intrudedgroundwater from the Salinas Valley Groundwater Basin (SVGB)3. The desalination plant willbe operated such that on an annual average basis, the plant would return desalinated water to theSVGB in an amount equal to the freshwater extracted from the slant wells.

    2 SPI Memorandum, Monterey Desalination Study Initial Scoping and Constraints Analysis, August 30, 20123 Direct Testimony of Richard C. Svindland Before the Public Utilities Commission of the State of California, filedApril 23, 2012

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    The preferred site for construction of the slant wells is an approximately 376 acre parcel of landwith 7,000 feet of ocean shoreline, located west of the proposed desal plant site. The angle of theslant wells will be determined by a proposed test well program, with a maximum well length ofapproximately 750 lineal feet. Wells would initially be placed on the beach, as far as possiblefrom the existing shoreline, but avoiding undisturbed dune habitat. This may cause some or all

    wells to be within the predicted 50-year erosion boundary; however, the expected useful life ofthe wells is less than 50 years. A contingency plan will be needed for relocating the wells inlandin the event that coastal erosion renders the wells inoperable4.

    Two design capacities are proposed: (1) seven wells operating at 2,200 gpm per well plus oneadditional well as a backup, for a total of 22 mgd (15,400 gpm) producing 9.0 mgd of productwater; (2) five wells operating at 1,840 gpm per well plus one additional well as backup, for atotal of 13.2 mgd (9,200 gpm) producing 5.4 mgd of product water4.

    Eight feed water pipeline alignments are being considered, all of which will be made of HDPE orFPVC, and will have a 30-inch or 36-inch diameter. The final selected alignment would includea parallel 16-in diameter pump to waste pipeline, to allow wasting of initial produced water froma pump following startup.

    The proposed treatment plant would be located on a vacant but disturbed 46-acre parcel west ofthe MRWPCA Regional Treatment Plant (RTP). The site would be accessed off of CharlesBenson Rd., a two-lane roadway that also serves the MRWPCA RTP along with the MontereyRegional Waste Management District. A new turn lane would need to be provided to allow safeaccess to the proposed desal plant for personnel and chemicals deliveries. Cal-Am is currently innegotiations to purchase the site from the existing land owner. Overall, land acquisition is not alarge concern as Cal-Am has the authority to exercise eminent domain privileges should anegotiated purchase prove untenable.

    Incoming seawater would be stored in two 0.5 MG storage tanks then pumped to granular mediapressure filters. Provisions would be included to pre-chlorinate the filter feed if necessary; as

    well as include proprietary media to remove iron and manganese should it be present in the rawseawater. Filter effluent would be dechlorinated if necessary, then flow to inline cartridge filtersprior to routing to the RO trains. The proposed RO system would be arranged as a full singlepass and partial second pass; with the second pass product making up 40 50 percent of the finalproduct supply. The first pass trains would include high pressure booster pumps and isobaricenergy recovery devices (ERDs); while the second pass trains would be equipped with highpressure booster pumps only. Operating recovery of the first pass trains would be roughly 45.5percent; while the second pass trains would operate at 90 percent. First and second pass trains,related pumps, and ERDs would be arranged in an N+1 configuration, with a total of fourprocess trains for the 5.4 mgd plant option and six process trains for the 9.0 mgd plant option.5

    The product water from the RO system would be post-treated with calcite and carbon dioxide forstabilization, along with addition of a corrosion inhibitor. For disinfection, the product would bedosed with sodium hypochlorite and stored in two, 1.0 MG storage tanks. Provisions may beincluded for a temporary or permanent UV disinfection system as well, should conditionswarrant (e.g., if additional disinfection credits are required).

    5

    4 RBF Memorandum, Monterey Peninsula Water Supply Project (MPWSP) Project Description, April 20, 20125 Cal-Am Response to SPI Questions, October 3, 2012

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    Overall the treatment approach is gauged to be sound. The greatest process risk is likelyassociated with the propose slant wells. Slant well intake systems can provide significantadvantages over traditional open ocean intakes including:

    Natural filtration

    Avoidance of impingement and entrainment of marine life No ocean construction impacts No permanent aesthetic impacts.

    However, slant wells can also pose more construction challenges than other well types as a resultof shallow construction angles and less vertical gravitational force. Slant wells need periodicaccess to the well head area. In areas where recreation exists (e.g., at a public beach) provisionmust be made to minimize disturbance6. Slant well intakes can be used with large desalinationplants, with seawater intake capacities of up to 50 mgd7. Maintenance of well specific capacitylong term is unknown; and elsewhere where employed the wells have been known to initiallydraw from an ancient marine aquifer containing high levels of iron and manganese 8. Lastly, the

    specific long term amount of groundwater uptake from the SVGB, estimated at up to 3 percent,is uncertain.

    Cal-Am plans to install a test slant well to establish site specific operating conditions andgenerate data which should help to confirm actual conditions and allow development ofappropriate mitigation strategies. Cal-Am has already included provisions for removing iron andmanganese across their pretreatment filters if necessary. The slant wells themselves can bescreened or installed at different angles to control the mix of seawater to diluent water extracted.Cal-Am is currently pursuing permits for the test well. An initial operating period of 6 12months is planned to develop data required for the EIR CEQA work. Cal-Am has indicated thatthe test period could extend as long as 18-24 months if additional data is required5. Should thetest well reveal slant wells to be problematic, a more conventional Ranney sub-surface intakewell could be used as an alternative. The conceptual layout would include three vertical caissonsand horizontal well clusters located across a 1,000 1,500 feet beach front area. Each caissonwould be capable of extracting up to 10 mgd.

    With either intake system, delivered raw seawater quality is likely to be good, with lowparticulate and silt density index (SDI) levels, making single-stage filtration an acceptablepretreatment approach. The RO process design is conservative, with a full first pass and partialsecond pass; including N+1 redundancy for all process units. The proposal does not includeacidification or antiscalant dosing to the first pass RO system feed water, but this is likelyacceptable as the planned recovery of the first pass system is limited to 45 percent. Feed andproduct storage tanks are arranges as 2 x 50 percent units, allowing the ability to take a tank out

    of service for maintenance. A preliminary site plan indicates the proposed site is sufficient to

    6 Williams, D.E. Design and Construction of Slant and Vertical Wells for Desalination Intake. IDA WorldCongress-Perth Convention and Exhibition Centre (PCEC) Perth, Western Austrailia September 4-9, 2011 REF:IDAWC/PER11-0507 Pankratz, T. A Review of Seawater Desal Intake, Pretreatment & Discharge Technologies. IDA Iran 06 WDTSProceedings September 17 & 18, 20068 Ghiu, S. 18 Month Demonstration of Slant Well Intake System Pretreatment and Desalination Technology forSeawater Desalination. WaterReuse Research Conference Proceedings, June 2012.

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    accommodate the proposed treatment plant facilities and related administrative and maintenancefacilities adequately.

    3.1.4 Residuals HandlingPlant residuals would be handled in a combination of storage and transfer systems. Backwashwaste from the filters would be collected in a 0.5 acre storage pond, with decant disposed withthe RO brine. RO brine would be sent to the MRWPCA ocean outfall. Analyses have shownthat the outfall has sufficient capacity to accommodate the projected peak brine flow from theplant under all but a worst case hydraulic loading scenario that is anticipated to last for sixhours9. In these situations, brine would temporarily be stored on site in a 3.0 MG detentionpond. The majority of the time (96 percent) the outfall is projected to have sufficient capacity.Waste residuals from the RO cleaning system would be neutralized and discharged with the brineto the outfall as well; or alternately to the site sanitary sewer if disposal with the brine is notpermitted.

    3.1.5 Feed Water CharacterizationThere has been no detailed characterization of plant feed water to date. Data will be generated aspart of the planned test well program.

    3.1.6 Quality of Project InformationAvailable documentation for the Cal-Am project is the most extensive and well developedamong the three proponents. Primarily this is a consequence of their involvement in thepreviously proposed regional project with Marina Coast Water District along with filings to theCPUC supporting their proposed project and development of required CEQA documentation.Appendices to their response to the TAC included the following:

    RBF Memorandum, Monterey Peninsula Water Supply Project (MPWSP) Capital andO&M Cost Estimate Update, April 20, 2012.

    RBF Memorandum, Monterey Peninsula Water Supply Project (MPWSP) ProjectDescription, April 20, 2012.

    Direct Testimony of Jeffrey T. Linam Before the Public Utilities Commission of theState of California, Filed April 23, 2012.

    Other project related documents were available on the Monterey Peninsula Water Supply Projectwebsite, including:

    California America Water Company, Coastal Water Project, Final EnvironmentalImpact Report, October 30, 2009.

    Download Filings for Proceeding A1204019

    9Trussel Technologies Inc. Technical Memorandum, MRWPCA Outfall Hydraulic Capacity Analysis, April 18,2012.

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    Presentations, including Technical Workshops on Monterey Peninsula Water SupplyProject (July 2012); Monterey Peninsula Water Supply Project Presentation (April2012); and Monterey Peninsula Water Supply Project Presentation (July 2012).

    Project Map (April 23, 2012). California American Water Application for Monterey Project (PDFA) California American Water Application for Monterey Project (POS, NOA,PDFA) California American Water Direct Testimony of Keith Israel, including a Technical

    Memo from Trussell Technologies, MRWPCA Outfall Hydraulic Capacity Analysis,April 18, 2012

    California American Water Direct Testimony of Jeffrey T. Linam California American Water Direct Testimony of Eric J. Sabolsice California American Water Direct Testimony of F. Mark Schubert, P.E.

    California American Water Direct Testimony of David P. Stephenson California American Water Direct Testimony of Richard C. Svindland California American Water Direct Testimony of Kevin Thomas

    Cal-Am also provided a response to questions from SPI, including the following documents:

    Capital Cost Worksheet O&M Cost Worksheet RBF Memorandum, Implementation Schedule Risk Analysis of Water Supply

    Alternatives, October 24, 2011

    RBF Memorandum, Cost Analysis of Water Supply Alternatives, October 19, 2011Overall the information is considered sufficient to evaluate the proposed project from a technicaland economic perspective.

    3.1.7 Omissions or Fatal FlawsOur evaluation and investigation of the proposed Cal-Am project did not uncover any perceivedfatal flaws or significant omissions of project information.

    3.2.1 Project PurposeDWD proposes a project that could serve both the defined demand within the Cal-Am servicearea for a desal supply of either 5,500 AFY or 9,000 AFY along with an expanded supply for theregion with a total plant capacity of 25,000 AFY. The project is predicated on development ofcertain components (e.g., the seawater intake, feed pipeline, brine pipeline) for the 25,000 AFYplant, with cost allocation based on treated water flow to defined customers.

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    3.2.2 Customers IdentifiedDWD seeks to supply either 5,500 AFY or 9,000 AFY to Cal-Am. The balance of the proposedplant capacity would be supplied to other customers. These may include the City of Santa Cruz,Soquel Creek Water Distict, Pajaro Valley Water Management Agency, areas of North MontereyCounty which may have a need and communities along the Highway 101 corridor betweenSalinas and Santa Clara.

    3.2.3 Adequacy of Treatment ApproachDWD proposes two plant design capacities to meet the 5,500 AFY and 9,000 AFY deliverytargets4.9 mgd and 9.1 mgd. Each of these capacities is different than the Cal-Am listed flowsof 5.4 mgd and 9.0 mgd, respectively.

    DWD proposes a new passive-screened open seawater intake drawing from Monterey Bay nearMoss Landing. Feed water would be withdrawn from a new 48-in. diameter pipe that would

    replace an existing pipeline previously used by PG&E for offloading fuel oil. The intake pipewould be 10,000 feet long and located at a depth of approximately 65-ft at its end. The pipeterminus would be screened with a passive, cylindrical wedge-wire screen constructed with 2mm. slot openings and a maximum design velocity of 0.5 fps through the screen to preventimpingement of marine organisms.

    The intake would cross Hwy. 1 through an existing utility tunnel; or space not permitting, a newcrossing. The line would connect to an existing, abandoned pump clear well at the Dynegy MossLanding Power Plant (MLPP). New pumps would be installed to transfer the influent seawaterfrom the clear well through a new 48-in diameter HDPE pipeline to the project site locatedroughly one mile north of MLPP along Hwy. 1, a location known as the Capurro Ranch. Enroute to the site, the water would transition through a proprietary warming system owned byDynegy, increasing its temperature from roughly 10 C up to as high as 34 C.

    The project site is currently occupied by an active vegetable distribution facility, with two large,refrigerated buildings on-site. The site is currently owned by MFLK Partnership, who are alsoequity partners in DeepWater Desal LLC. DWD has secured a 34-year ground lease for the sitewith an option to extend it for two successive 32-year periods. The site area is 8.14-acres; andDWD has secured an option to lease an additional 8-acre parcel adjacent to the site shouldadditional area be required for plant construction.

    No feed water storage tanks are proposed, with the supply pumped directly to granular mediapressure filters. Provisions would be included to pre-chlorinate the filter feed if necessary; aswell as include a filter aid coagulant (ferric chloride). Filter effluent would be dechlorinated ifnecessary, then flow to inline cartridge filters prior to routing to the RO trains. The proposed ROsystem would be arranged as a single pass system. The trains would include high pressurebooster pumps and isobaric ERDs. Operating recovery of the first pass trains would be variablebetween 43 and 47 percent. The RO trains, related pumps, and ERDs would be arranged in an

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    N+1 configuration, with a total of three process trains for the 4.9 mgd plant option and sixprocess trains for the 9.1 mgd plant option.10

    The product water from the RO system would be post-treated with calcite and carbon dioxide forstabilization, along with addition of a corrosion inhibitor. For disinfection, the product would bedosed with sodium hypochlorite and stored in a single 2.5 MG storage tank.

    Overall the treatment approach is gauged to be sound, though the proposed RO system designwould produce a lower quality product than the proposed Cal-Am system, consisting solely of asingle pass of RO treatment. The greatest process risk is likely associated with the proposedopen intake and feed water delivery system. Water quality sampling conducted at depth hasindicated the raw seawater will likely be low in turbidity and suspended solids. This is backedup by available literature. Intake depth can have a significant impact on water quality. Sun raysare absorbed by the ocean surface, limiting photosynthesis and algae quantity as depth increases.It is for this reason that deep water intakes typically provide feed water with less biologicalactivity and fewer suspended solids than conventional open water/surface intakes. However, thedisadvantage is that seawater temperature decreases with depth, increasing either membrane

    surface area or feed pressure required for treatment. On the other hand, more stable annualtemperatures at this depth may facilitate plant design and operation11. To address thetemperature issue, DWD has proposed warming the supply in proprietary system on the MLPPsite. The proposed system is subject to a non-disclosure agreement at present, limiting thepublicly available information. However, it appears the system will likely be integral tooperations at the MLPP, providing a cooling water source. The approach is certainly synergistic,but it also in effect links operations between MLPP and the desal plant to a certain extent,introducing potential reliability issues. In addition, there is no experience with the effect ofwarming a deep source supply. There is potential for the increase in temperature to cause anincrease in biological activity and associated biological fouling within the treatment process.There is no way to gauge the potential magnitude of this risk element at this time. The DWD

    project proponents do not consider it a large concern and have not proposed a pilot test programon the candidate source water and overall pretreatment process. The issue becomes what wouldbe the impact of a problem discovered once the project was built? Remedies may be limited ifthe warming process is contingent on an agreement between Dynegy and DWD. If the warmingprocess could be bypassed, then the issues with cold water treatment would come into play,increasing RO system operating pressures and potentially exceeding operating capabilities ofinstalled pumping equipment.

    The RO process design from an operations perspective is conservative, with N+1 redundancy forall process units. There is no proposed feed storage tank, which is considered acceptable; but thelack of any type of redundancy in product storage is a concern; as any required maintenance onthe tank would necessarily require a shutdown of the treatment facility unless suitable temporary

    storage could be obtained. A preliminary site plan indicates the proposed site is sufficient toaccommodate the proposed treatment plant facilities and related administrative and maintenancefacilities adequately.

    10 DWD Response to SPI Questions, September 12, 201211 Cartier G., Corsin P. - Description of Different Water Intakes for SWRO Plants. IDA World Congress-Maspalomas, Gran Canaria Spain October 21-26, 2007 - REF: IDAWC/MP07-185.

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    From a process perspective, the proposed pretreatment system design is likely acceptable. Thereis sufficient precedence for single stage filtration on open seawater intakes among successfullyoperating facilities to provide confidence in this approach

    12. The proposal does not include

    acidification or antiscalant dosing to the first pass RO system feed water, but this is likelyacceptable if recovery is limited to the proposed operating range. A larger concern is with the

    RO system process design as a single pass system which would produce a treated product supplywith TDS, boron and chloride levels above the existing supplies from the Carmel River. It is ourrecommendation that any desalination system incorporating RO as the primary process forPeninsula customers include a partial (at least 40 percent) second pass RO system to furtherimprove product quality, especially at the elevated temperature operation proposed.

    3.2.4 Residuals HandlingBackwash waste from the filters would be collected in a 175,000 gallon settling tank, with decantsent to a separate 150,000 gallon tank for disposal along with the RO brine. RO brine would besent to back to MLPP for disposal along with the plant cooling water through their existing ocean

    outfall at a projected dilution ratio between 20 and 60 to 1. DWD also proposes to neutralizechemical cleaning wastes and dispose of them with the brine as well.

    During our site visit it was made clear that an agreement between DWD and Dynegy for use ofthe cooling water outfall was still subject to negotiation among the parties.

    3.2.5 Feed Water CharacterizationDWD has a buoy in the area of the proposed intake collecting data on salinity, temperature andturbidity at fixed intervals. Comprehensive analytical data is not available at this time. DWDhas retained Tenera Environmental to conduct a 12 month study on impingement andentrainment issues. Sampling in support of the study is ongoing. Tenera did conduct apreliminary analysis based on available information and a proposed intake flow of 25 mgd. Thatreport found low projected levels of entrainment. However, additional more detailed analysesare required based on site specific data; in particular to assess the presence of a large, verticalmixing zone at the interface of the submarine canyon in the bay13.

    3.2.6 Quality of Project InformationAvailable documentation for the DWD project is adequate at this stage of project development.DWD has not yet progressed with their formation of a joint powers authority (JPA) for projectimplementation and production of environmental permitting packages. Information collected to

    data has largely been in service of defining the project approach, securing agreements, anddeveloping project cost estimates. The nature of the agreement between DWD and Dynegy isstill confidential between the parties.

    A listing of documents provided in addition to the response to the TAC is as follows:

    12 DWD Response to SPI Questions, September 8, 2012.13 Tenera Environmental, Preliminary Modeling of Potential Impacts from Operation of a Desalination FacilityOcean Intake, August 22, 2012.

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    Product Water Pipeline Alignment Intake Pipeline Hydraulic Grade Line Draft Design Criteria Tenera Preliminary Intake Assessment Conductivity, Temperature and Turbidity Data May 30 June 12, 2012. Raw Water Characterization Program Memo Capital and O&M Cost Estimate Worksheets Site Layout for Capurro Ranch Presentation: An Oceanographic Solution to Product Freshwater, August 2012

    Overall the information is considered sufficient to evaluate the proposed project from a technicaland economic perspective.

    3.2.7 Omissions or Fatal FlawsWe have not identified any fatal flows with the DWD proposed system. The only omissions ofinformation are acknowledged by DWD and related to the agreements between DWD andDynegy.

    3.3.1 Project PurposePML proposes a project that could serve the defined demand within the Cal-Am service area for

    a desal supply of either 5,500 AFY or 9,000 AFY.

    3.3.2 Customers IdentifiedPML seeks to supply either 5,500 AFY or 9,000 AFY to Cal-Am. Supply to other customers isnot proposed.

    3.3.3 Adequacy of Treatment ApproachPML proposes two plant design capacities to meet the 5,500 AFY and 9,000 AFY deliverytargets4.8 mgd and 9.1 mgd. Each of these capacities is different than the Cal-Am listed flowsof 5.4 mgd and 9.0 mgd, respectively. The difference results from their targeting deliveries of5,000 AFY and 10,000 AFY in their response to the TAC and subsequent information providedto SPI.

    PML proposes to use an existing seawater intake system originally installed to serve the KaiserRefractories Moss Landing Magnesia Plant back in 1968the same site that is now called theMoss Landing Commercial Park (MLCP). The pump station draws from the Moss LandingHarbor and supplies water to the site through two 36-in diameter pipelines that cross beneath

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    Hwy. 1 through a pair of 72-in corrugated steel conduits. One of the pipelines has beenupgraded to steel throughout its length; while the second maintains a section of the original woodstaved piping on site. Proponents have also indicated the ability to repurpose the existing siteseawater outfall as dual intake-outfall conduit extending into the Monterey Bay out front of MossLanding Harbor. The existing concrete outfall is 51-in internal diameter; and could have a new

    intake line installed in the annular space; with brine flowing out in the opposite direction. Costestimates provided to SPI were based on use of the existing intake system so this approach formsthe basis of our evaluation.

    The 1968 drawings show the installation of seven pumps. The condition of the pumps at thistime is unknown; but would likely require rehabilitation and rework to supply the proposedtreatment plant. The pump bowls reportedly draw from below the harbor seafloor, but the actualdepth is unknown.

    The MLCP site still contains infrastructure from the time it was employed as a magnesiumextraction facility. The total site occupies roughly 200 acres; with a proposed 25 acre parceloffered for sale or lease as part of the proposed desal treatment plant. Available facilities offeredfor use include the following:

    Intake pumps and pipeline and outfall pipeline.

    Up to four 5.0 MG concrete storage tanks.

    A 12kV, 12,000 amp electrical service along with two 1,000 amp engine generators.

    Rail transportation terminal.

    Non-exclusive easements for site access.

    Non-exclusive use of a 2,100 gpm well supply source.

    A 5,000 gpd trailer-mounted pilot plant.

    Up to 20,000 sq. ft. of existing buildings.

    Existing infrastructure is in various states of repair as detailed in two site investigations14,15

    andwould require some refurbishment and rework to be acceptable for integration into a municipaldrinking water facility. Portions of the site are likewise located within the flood plain16 andconstructed facilities would need to be built in accordance with any ensuing requirements.

    The proposed PML treatment system would include inlet screens, booster pumps, single stagepressure filters, an ultrafiltration (UF) membrane treatment system, antiscalant dosing system,high pressure booster pumps with pressure exchange type ERDs, single pass RO system, post-treatment system, and product storage and distribution pump station. The RO system wouldoperate at 40 percent recovery and limit operating flux to 8 gfd. The UF system would operate at

    a proposed flux of 35 gfd.

    14Replacement Cost Approaisal Summary Report, prepared by Landmark Realty Analysts, Inc., October 3, 2011.15 Structural Evaluation, Intake & Outfall Pipelines, Intake Pump Station and Water Storage Reservoirs, ThePeoples Moss Landing Water Desalination Project, Moss Landing Green Commercial Park, Modd Landing, CA,August 14, 2012.16 Monterey County Planning & Building Inspection Department; Meeting September 30, 2004, Agenda Item 6.

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    The product water from the RO system would be post-treated with calcite and carbon dioxide forstabilization, along with addition of a corrosion inhibitor. For disinfection, the product would bedosed with sodium hypochlorite and stored in existing tankage on site.

    PML did not provide a detailed list of equipment or a site layout plan, stating that it was too early

    in the development of their project to have that information developed. It is therefore somewhatdifficult to gauge the robustness of their approach. From the narrative description provided andlisted membrane area assumptions, it is not clear that the major UF and RO train equipmentcontain redundant process units.

    From a process perspective, the proposed pretreatment system design may be acceptable. Thelargest unknown is the quality of water that will be extracted from the Moss Landing Harbor.There could be organics, metals and other contaminants entrained in the sediments overlayingthe supply pumps that could complicate treatment. PML has proposed conducting a pilot studyprogram prior to finalizing their process design, so this should help allay concerns. A previouspilot study conducted at MLPP found that direct UF pretreatment operated in concert with acoagulant was effective at pretreating a supply drawn from the Moss Landing Harbor, but thatflux should be limited to 30 gfd17.

    A larger concern is with the RO system process design as a single pass system similar to theDWD approach. As stated in that discussion, we recommend including a partial second pass ROtreatment system to produce a final product quality more in keeping with current supplies in thedistribution system.

    3.3.4 Residuals HandlingPretreatment residuals would come from the proposed filters and UF process units. A backwashrecovery system is proposed, with decant sent to the outfall with the RO system brine stream.

    Neutralized UF and RO cleaning wastes would be treated similarly; or recovered for reuse withinthe MLCP. Brine would be discharged to the existing outfall.

    The outfall is currently not in use and there is evidence of disrepair in a video survey conductedsometime prior to 200818 . The video shows evidence of several areas of decoupling along themain outfall alignment. Also, according to the original plans, the outfall was installed belowgrade until the diffuser section19. However, portions of the main outfall appear to be currentlyuncovered; and one section shifted uppossibly as a consequence of the 1989 Loma Prietaearthquake. Many of the diffusers are clogged and covered with marine growth; and from theterminus of the outfall it appears it may be largely filled with sandup to half of thecircumference. Consequently a fair amount of rehabilitative work would be required to place theoutfall into service, and more detailed assessmentincluding an inspection of the interior of theoutfallis warranted.

    17 Coastal Water Project Pilot Plant Report, May 2010, MWH.18 Outfall Video, Moss Landing Marine Lab, California State University.19 Seawater Outfall for Kaiser Aluminum and Chemical Corporation, Moss Landing, California, by KaiserEngineers, 1971.

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    3.3.5 Feed Water CharacterizationPML does not at this point have analytical data characterizing the proposed raw water supply. Itwill presumably be collected during their planned pilot test program.

    3.3.6 Quality of Project InformationThe PML project is the least developed among the three as evidenced by the level of informationprovided. They were however very forthcoming in sharing all that was available, includingoriginal construction plans for the intake and outfall, video survey of the outfall, and other sitespecific reports.

    A listing of documents provided in addition to the response to the TAC is as follows:

    Construction Plans: Seawater Outfall

    Construction Plans: Relocation of Sea Water Intake

    The Peoples Moss Landing Water Desal Project, Important New Updates, July 2012

    Response to SPI Questions, September 4, 2012 and September 27, 2012

    Environmental Issues and Constraints Report, SMB Environmental, September 2012

    Structural Evaluation, JAMSE Engineering Inc., August 2012.

    Replacement Cost Appraisal Summary Report, Landmark Realty Analysts, Inc.,October 2011.

    Adopted Waste Discharge Requirements Order No. R3-2009-002, National PollutantDischarge Elimination System (NPDES) Permit No. CA0007005 Moss LandingCommercial Park and Moss Landing Cement Company, Moss Landing Cement

    Company Facility, Monterey County, March 2009.Overall, the lack of specificity as to the proposed plant facilities makes the technical andeconomic evaluation difficult and forces us to make additional assumptions on our own.

    3.3.7 Omissions or Fatal FlawsWe have not identified any fatal flows with the PML proposed system. The primary omission isthe lack of defined lists of equipment in order to assist in validating cost estimates.

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    This section discusses the following performance issues for each project:

    Plant design capacity Targeted product water quality Disinfection strategy

    Plant design capacity refers to the proposed instantaneous flow achieved by a given plant designto achieve the annual produced water flow of 9,000 AFY or 5,500 AFY. The design capacity ofa facility impacts both its construction and operating cost, and must take account of issues suchas equipment redundancy, periodic maintenance, and overall online operating factor.

    The issue of product water quality is closely tied to the proposed demineralization systemprocess design of each facility. As discussed previously, DWD and PML have proposed singlepass RO systems; while Cal-Am has proposed a partial (40 percent) second pass system. The two

    approaches will produce different qualities of final product water from an overall salinityperspective, as well as levels of boron and chloride.

    In addition to salinity and individual constituent targets, the design must also achieve regulatorypathogen removal thresholds. The California Department of Public Health (CDPH) has primacyto regulate public water systems within the State. As such, they will review these proposedtreatment approaches for compliance with the Surface Water Treatment Rule (SWTR) and theLong Term 2 Enhanced Surface Water Treatment Rule. It is anticipated the slant wells proposedfor the Cal-Am project would be deemed groundwater under the influence of surface water andsubject to the surface water regulations, as would the open intake sources for DWD and PML.

    Pathogen removal/inactivation requirements are quantified in increments of influent to effluent

    concentration, expressed in a log scale. For example 3-log removal is 99.9%. CDPH willestablish the log removal requirements of a project based on information on the quality of thesource water and other factors. The expected ranges of possible requirements for these projectsare 3-5 for Giardia; 2-4 for cryptosporidium (crypto); 4-6 for virus. Some project proponentshave indicated an expectation the requirements will fall at the low end of the ranges.

    Each treatment process is assigned a log removal credit for each pathogen. By summing thecredits of all processes in the multi-barrier approach (filters, RO, disinfection, etc.) a total creditis achieved to meet or exceed the regulatory requirement. Under the disinfection strategydiscussion we consider the removal credits likely achieved by the proposed projects.

    4.1.1 Plant Design CapacityDefined demand requirements for the proposed supply to the Monterey Peninsula customers are5,500 AFY and 9,000 AFY. Plant designs are rated in instantaneous production capacities forthe purposes of sizing equipment (pumps, RO membrane trains, etc.) in units of mgd. 1.0 mgd isequivalent to annual production rate of 1,120 AFY. The required minimum plant capacity wouldtherefore translate to 4.9 mgd or 8.0 mgd. This however is not necessarily what we wouldrecommend as a conservative municipal plant design basis. Equipment breaks down, membranes

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    require cleaning, power outages occur. Without excess treatment capacity or high levels ofcomponent redundancy, annual deliveries could fall short.

    Cal-Am has proposed a design capacity basis of 5.4 mgd or 9.0 mgd. These capacities are fairlyclose to what you would get by assuming the treatment plant is on-line and producing water 90percent of the time, which results in capacities of 5.45 mgd and 8.92 mgd. A 90 percent on-line

    factor is consistent in our experience of a well-designed and operated municipal RO plant thatdoes not have redundant process units (e.g., RO trains). In Cal-Ams case, they are proposingredundant process units, so its likely the facility will be capable of producing its nameplatecapacity of 5.4 mgd or 9.0 mgd better than 90 percent of the time.

    An additional issue specific to Cal-Am however is the potential extraction and return ofgroundwater from the SVGB. Cal-Am estimates as much as 8 percent of the plants annualproduction capacity may need to be returned to the basinup to 780 AFY for the 9,000 AFYdemand scenario20. This has the effect of increasing the annual flow requirement to 5,960 AFYor 9,780 AFY; and corresponding minimum plant design capacity to 5.3 mgd or 8.7 mgd.Looked at another way, the plant would need to run at the proposed design capacity roughly 98percent of the time to meet the higher delivery requirement. With the level or redundancy in Cal-Ams design we consider this achievable but not overly conservative.

    4.1.2 Targeted Product Water QualityThough Cal-Am has produced a good degree of information to date with regard to their proposedproject, the majority has been in service of supporting their CEQA and CPUC approvalprocesses. They have specifically not developed a target product water quality specification,beyond stating the final product water will meet all State Maximum Contaminant Levels (MCLs)and be non-corrosive. Rational for a partial second pass RO system includes concerns overlevels of boron, chloride and sodium in the final product water as well20. Also in a presentation,

    Cal-Am projected treate