Agenda-Item-Number-3-PSA-Well-4-Phase-1-Prelim-Design-LSCE-031726-FINAL — Sebastopol City Council, March 17, 2026 (part 1 of 2)

CITY OF SEBASTOPOL CITY COUNCIL
AGENDA ITEM REPORT FOR MEETING OF: March 17, 2026
=========================================================================================== To: Honorable Mayor and City Councilmembers
From: Oriana Hart, Public Works Director
Toni Bertolero, Public Works Engineer
Subject: Well 4 Replacement Project – Phase 1 Preliminary Design Professional Services Agreement =========================================================================================== RECOMMENDATION:

That the City Council adopt a resolution to approve the Professional Services Agreement with Luhdorff & Scalmanini Consulting Engineers for the preliminary design of the Well Replacement Project (CIP #0822-24.06) for amount not to exceed $378,095.00 and authorize the Interim City Manager to sign the Agreement and to authorize a contingency of 5 percent, if needed.

EXECUTIVE SUMMARY:

Council approved the Capital Improvement project for the design of the Well 4 Replacement Project in the adopted Fiscal Year 2025-26 Budget. The original scope for the design did not include test hole drilling and installation of a monitoring well and the The City released a Request for Proposal (RFP) on November 3,2025 and two (2) bids were received: 1) Hazen and Sawyer, and 2) Luhdorff & Scalmanini Consulting Engineers (LSCE). Public Works Staff consisting of the Public Works Engineer, the Public Works Supervisor and the Engineering Technician interviewed both firms on January 12, 2026. While both firms were equally qualified to perform the work, the approach and proposed work plan by LSCE was superior to Hazen and Sawyer’s and results in a lower cost for the preliminary and final design of Well 4.

In addition, the LSCE team included a highly experienced engineer well versed in water grants and State Revolving Fund (SRF) loans.

The design work consists of two phases. Phase 1 is for the preliminary design of Well 4 with the following scope:

Task 1: Project Management
Task 2: Funding Assistance and Support
Task 3: Permitting Assistance
Task 4: Site Specific Investigation
The Fee Estimate for the Phase 2 work is not-to-exceed $378,095.00. The adopted CIP Fiscal Year 2025-26 budget for the Well 4 Project is $400,000.00.

The future, Phase 2 final design, would commence after the site investigation report is completed. Based on the test hole and monitoring well sampling performed under Task 4, a basis of design for the Well 4 final design can be established. This Phase 2 work, as well as Phase 3 for the construction and installation of the new well, will be included in the future Fiscal Year 2026-27 CIP budget.

This item was presented to the Budget Committee on March 2, 2026. No comments or concerns with this item were raised at the meeting.

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BACKGROUND AND DISCUSSION:

The Well 4 Replacement Project (CIP #0822-24.065) was approved in the Fiscal Year 2025-26 CIP budget. The funding source is Water Capital Fund 501. Replacement of this well was originally constructed in 1953 and supplies nearly half of the City’s water customers with an annual production of 157 million gallons. Well 4 is equipped with a granular activated carbon (GAC) filtration system that addresses the water quality concerns in the groundwater, namely arsenic and PCE from a nearby old dry cleaner site. The new proposed well will be drilled on the existing site but must be sited at least 50 feet away from the current well.

The City released a Request for Proposal (RFP) on November 3,2025 to six (6) engineering firms with well design experience. The original due date for the Proposals was December 1, 2025 but was extended to December 8, 2025 to allow for more time due to the complexity of the scope. Two (2) bids were received: 1) Hazen and Sawyer, and 2) Luhdorff & Scalmanini Consulting Engineers (LSCE). The proposals were reviewed by the Public Works Engineer, the Public Works Supervisor and a geologist from the Town of Windsor who is currently working on a well installation project for the Town. The interview occurred on January 12, 2026. All three members of the interview panel were in agreement which firm was the best qualified consultant.

While both firms were very qualified to perform the work, the approach and proposed work plan by LSCE was superior to Hazen and Sawyer’s and results in a lower cost for the preliminary and final design of Well 4. In addition, the LSCE team included a highly experienced engineer well versed in water grants and State Revolving Fund (SRF) loans. The selection process included multiple phone calls/meetings subsequent to the interview to confirm that the best qualified consultant is selected.

STAFF ANALYSIS:

A Water Rate Study was prepared in June 2024 and the water model for the study accounted for the $400,000 in Fiscal Year 2025-26. The water model estimated that the construction of the new well would be financed through a loan. Staff is currently working on the Fiscal Year 2026-27 CIP budget and the cost of Phase 2 final design is estimated at $261,454 and will be included in the proposed CIP for FY 26-27.

Phase 1 will include the following tasks:

Task 1. Project meetings, coordination and project administration.

Task 2. Preparation of the application including the construction funding package, environmental (CEQA-Plus) documentation, and the financial package. It is assumed that the best loan package will be the SRF loan with the State, however, there may be opportunities for alternate funding sources, if the City chooses another grant or loan package.

Task 3. Preparation of applications for State Water Board, Department of Drinking Water (DDW) water permit for the construction of the well, and the CEQA documentation for the construction.

Task 4. Initial site assessment consisting of well siting, hydrogeologic review and investigation of possible sources of groundwater contamination in the vicinity of the well site; test hole drilling and installation of a monitoring well. The monitoring well will allow for collection of zone-specific water levels and water quality samples. This task will include water quality sampling and analysis. This task includes preparation of a well design report for the basis of the final design (Phase 2).

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CITY COUNCIL GOALS/PRIORITIES/ AND OR GENERAL PLAN CONSISTENCY:

This agenda item represents the City Council goals/priorities as follows:

Goal 3 – Infrastructure: Maintaining High Quality Infrastructure, Facilities and Services includes repairing/replacing outdated city facilities, improving streets, stormwater and water and wastewater infrastructure.
• Priority 7: Well 4 Updates and Funding
This agenda item represents the City Council General Plan Consistency (if applicable):

Community Services and Facilities (CSF 1-5): Require development, infrastructure, and long-term planning projects to be consistent with all applicable City infrastructure plans, including the Water Master Plan, and the Capital Improvement Program.

FISCAL IMPACT:

There is no fiscal impact with this approval; Cost for this contract is not to exceed $378,095 and is within the adopted CIP budget of $400,000.

The future Phase 2 final design will be included in the proposed Fiscal Year 2026-27 budget. It is estimated that financing will be required for the construction of the replacement well and will be included in the future Fiscal Year 2027-28 budget. The City is negotiating with the parties responsible for the contamination from the former dry-cleaning site to contribute to funding the cost of the well replacement project.

COMMUNITY OUTREACH:

This item has been noticed in accordance with the Ralph M. Brown Act and was available for public viewing and review at least 72 hours prior to schedule meeting date. The City has also used social media to promote and advertise the City Council Meeting Agenda Items.

As of the writing of this agenda item report, the City has not received any public comment. However, if staff receives public comment from interested parties following the publication and distribution of this agenda item report, such comments will be provided to the City Council as supplemental materials before or at the meeting.

RESTATED RECOMMENDATION:

CITY COUNCIL OPTION(S):

City Council could choose not to approve the agreement with Luhdorff & Scalmanini Consulting Engineers and provide direction to staff.

ATTACHMENTS:
1-Resolution
2-Professional Services Agreement with LSCE
3-Request for Proposals (RFP)
4-Proposal from LSCE
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APPROVALS:

Department Head Responsible for Agenda Item: Approval Date: 3/5/26 CEQA Determination (Community Development/Planning): Approval Date: 3/5/26 The proposed action is Exempt from CEQA pursuant to §15306.

Administrative Services (Financial): Approval Date: N/A Costs authorized in City Approved Budget:  Yes ☐ No ☐ N/A Water Capital Fund 501
City Attorney Approval Approval Date: 3/4/26
City Manager Approval: Approval Date: 3/11/26
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RESOLUTION NO. ####-2026

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF SEBASTOPOL

APPROVING PROFESSIONAL SERVICES AGREEMENT WITH LUDHORFF & SCALMANINI CONSULTING ENGINEERS FOR PROFESSIONAL SERVICES IN AN AMOUNT OF $378,095 PLUS 5% CONTINGENCY FOR PHASE 1 PRELIMINARY DESIGN OF WELL 4 REPLACEMENT PROJECT CIP #0822-24.06
WHEREAS, the City Council approved the Capital Improvement Project for the Well 4 Replacement Project in the adopted Fiscal Year 2025-26 Capital Improvement Plan; and WHEREAS, the City released a Request for Proposals to six (6) engineering firms on November 3, 2025; and WHEREAS, the City received two Proposals and Ludhorff & Scalmanini Consulting Engineers was selected as the most qualified firm for the service and determined to be responsive, fair and reasonable.

NOW, THEREFORE, BE IT RESOLVED that the City Council of the City of Sebastopol does hereby approve the Professional Services Agreement with Luhdorff & Scalmanini for the Phase 1 Preliminary Design of Well Replacement Project (CIP #0822-24.06) for amount not to exceed $378,095.00. and authorizes the Interim City Manager to sign the agreement and amendments to the agreement of up to 5% of the approved amount (if needed).

The above and foregoing Resolution was duly passed, approved, and adopted at a meeting by the City Council on the 17th day of March 2026 by the following vote:

VOTE:

Ayes:

Noes:

Abstain:

Absent:

APPROVED: _______________________________________
Mayor Jill McLewis
ATTEST: _______________________________________________________________ Mary Gourley, Interim City Manager/City Clerk, MMC
APPROVED AS TO FORM: __________________________________________________ Alex Mog, City Attorney
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City of Sebastopol Agreement for Professional Services Page 1 of 10

AGREEMENT FOR PROFESSIONAL SERVICES
THIS AGREEMENT, made and entered into on ________________ by and between the City of Sebastopol, located in the County of Sonoma, State of California (City), and Luhdorff & Scalmanini Consulting Engineers (Consultant).

RECITALS:

A. City desires to employ Consultant to furnish professional services in connection with the project described as Phase 1 Preliminary Design of the Well 4 Replacement Project CIP #0822-24.06.

B. Consultant has represented that Consultant has the necessary expertise, experience, and qualifications to perform the required duties.

NOW, THEREFORE, in consideration of the mutual premises, covenants, and conditions herein contained, the parties agree as follows:

SECTION 1 – BASIC SERVICES
Consultant agrees to perform the services set forth in the Consultant’s scope of services shown on Exhibit A, “Proposal” and made part of this Agreement.

SECTION 2 – ADDITIONAL SERVICES
Consultant shall not be compensated for any services rendered in connection with its performance of this Agreement which are in addition to or outside of those set forth in this Agreement or Exhibit A, unless such additional services and compensation are authorized in advance and in writing by the City Council or City Manager of the City.

SECTION 3 – TIME FOR COMPLETION
The time for completion of services shall be as identified in Exhibit A.

SECTION 4 – COMPENSATION AND METHOD OF PAYMENT
A. Subject to any limitations set forth in this Agreement, City agrees to pay consultant the amount specified in Exhibit A, Proposal dated February 25, 2026, attached hereto and made a part hereof. Total compensation shall not exceed a total of $378,095.00, unless additional compensation is approved in accordance with Section 2.

B. Consultant shall furnish to City an original invoice for all work performed and expenses incurred during the preceding month. The invoice shall detail charges by the following categories if applicable: labor (by sub-category), travel, materials, equipment, supplies, subconsultant contracts, and miscellaneous expenses. City shall independently review each invoice submitted to determine whether the work performed, and expenses incurred are in compliance with the provisions of this Agreement. If no charges or expenses are disputed, the invoice shall be approved and City will use its best efforts to cause Consultant to be paid within 30 days of receipt of invoice. If any charges or expenses are disputed by City, the original invoice shall be returned by City to Consultant for correction and resubmission. If the City reasonably determines, in its sole judgment, that the invoiced charges and expenses exceed the value of the services performed to date and that it is probable that Agenda Item Number 3
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City of Sebastopol Agreement for Professional Services Page 2 of 10 the Agreement will not be completed satisfactorily within the contract price, City may retain all or a portion of the invoiced charges and expenses. Within thirty (30) days of satisfactory completion of the project, City shall pay the retained amount, if any, to Consultant.

C. Payment to the Consultant for work performed pursuant to this Agreement shall not be deemed to waive any defects in work performed by Consultant.

SECTION 5 – STANDARD OF PERFORMANCE
Consultant represents and warrants that it has the qualifications, experience and facilities necessary to properly perform the services required under this Agreement in a thorough, competent and professional manner. Consultant shall at all times faithfully, competently and to the best of its ability, experience and talent, perform all services described herein. In meeting its obligations under this Agreement, Consultant shall employ, at a minimum, generally accepted standards and practices utilized by persons engaged in providing services similar to those required of Consultant under this Agreement.

SECTION 6 – INSPECTION AND FINAL ACCEPTANCE
City may inspect and accept or reject any of Consultant’s work under this Agreement, either during performance or when completed. City shall reject or finally accept Consultant’s work within sixty (60) days after submitted to City, unless the parties mutually agree to extend such deadline. City shall reject work by a timely written explanation, otherwise Consultant’s work shall be deemed to have been accepted. City’s acceptance shall be conclusive as to such work except with respect to latent defects and fraud. Acceptance of any of Consultant’s work by City shall not constitute a waiver of any of the provisions of this Agreement including, but not limited to, the sections pertaining to indemnification and insurance.

SECTION 7 – INSURANCE REQUIRED
Consultant shall procure and maintain for the duration of the contract insurance against claims for injuries to persons or damages to property which may arise from or in connection with the performance of the work hereunder by the Consultant, its agents, representatives, or employees.

MINIMUM SCOPE AND LIMIT OF INSURANCE
Coverage shall be at least as broad as:

1. Commercial General Liability (CGL): Insurance Services Office Form CG 00 01 covering CGL on an “occurrence” basis, including products and completed operations, property damage, bodily injury, and personal & advertising injury with limits no less than $2,000,000 per occurrence. If a general aggregate limit applies, either the general aggregate limit shall apply separately to this project/location (ISO CG 25 03 or 25 04) or the general aggregate limit shall be twice the required occurrence limit.

2. Automobile Liability: Insurance Services Office Form Number CA 0001 covering, Code 1 (any auto), or if Consultant has no owned autos, Code 8 (hired) and 9 (nonowned), with limit no less than $1,000,000 per accident for bodily injury and property damage.

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City of Sebastopol Agreement for Professional Services Page 3 of 10

3. Workers’ Compensation insurance, as required by the State of California, with Statutory Limits, and Employer’s Liability Insurance with limit of no less than $1,000,000 per accident for bodily injury or disease.
(Not required if consultant provides written verification that it has no employees)

4. Professional Liability (Errors and Omissions) Insurance appropriates to the Consultant’s profession, with limit no less than $2,000,000 per occurrence or claim, $2,000,000 aggregate. The Retroactive Date must be shown and must be before the date of the contract or the beginning of contract work. Insurance must be maintained and evidence of insurance must be provided for at least five (5) years after completion of the contract of work. If coverage is canceled or non-renewed, and not replaced with another claims-made policy form with a Retroactive Date prior to the contract effective date, the Consultant must purchase “extended reporting” coverage for a minimum of five (5) years after completion of contract work. A copy of the claims reporting requirements must be submitted to the City of Sebastopol for review.

If the Consultant maintains broader coverage and/or higher limits than the minimums shown above, the City of Sebastopol requires, and shall be entitled to, the broader coverage and/or higher limits maintained by the Consultant. Any available insurance proceeds in excess of the specified minimum limits of insurance and coverage shall be available to the City of Sebastopol.

Other Insurance Provisions
The insurance policies are to contain, or be endorsed to contain, the following provisions:

The City of Sebastopol, its officers, officials, employees, and volunteers are to be covered as additional insureds on the CGL policy with respect to liability arising out of work or operations performed by or on behalf of the Consultant including materials, parts, or equipment furnished in connection with such work or operations.

General liability coverage can be provided in the form of an endorsement to the Consultant’s insurance at least as broad as one of the following ISO ongoing operations Forms: CG 20 10 or CG 20 26 or CG 20 33 (not allowed from subcontractors), or CG 20 38; and one of the following ISO completed operations Forms: CG 20 37, 2039 (not allowed from subcontractors), or CG 20 40.

Primary Coverage
For any claims related to this contract, the Consultant’s insurance coverage shall be primary insurance coverage at least as broad as ISO CG 20 01 04 13 as respects the City of Sebastopol, its officers, officials, employees, and volunteers. Any insurance or self-insurance maintained by the City of Sebastopol, its officers, officials, employees, or volunteers shall be excess of the Consultant’s insurance and shall not contribute with it.

Notice of Cancellation
Consultant shall provide immediate written notice if (1) any of the required insurance policies is terminated; (2) the limits of any of the required polices are reduced; (3) or the deductible or self-insured retention is increased. In the event of any cancellation or reduction in coverage or limits of any insurance, Consultant shall forthwith obtain and submit proof of substitute insurance.

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City of Sebastopol Agreement for Professional Services Page 4 of 10 Waiver of Subrogation
Consultant hereby grants to the City of Sebastopol a waiver of any right to subrogation which any insurer of said Consultant may acquire against the City of Sebastopol by virtue of the payment of any loss under such insurance. Consultant agrees to obtain any endorsement that may be necessary to affect this waiver of subrogation, but this provision applies regardless of whether or not the City of Sebastopol has received a waiver of subrogation endorsement from the insurer. However, the Workers’ Compensation policy shall be endorsed with a waiver of subrogation in favor of the City of Sebastopol for all work performed by the Contractor, its employees, agents, and subcontractors.

Self-Insured Retentions
Self-insured retentions must be declared to and approved by the City of Sebastopol. The City of Sebastopol may require the Consultant to provide proof of ability to pay losses and related investigations, claim administration, and defense expenses within the retention. The policy language shall provide, or be endorsed to provide, that the self-insured retention may be satisfied by either the named insured or the City of Sebastopol.

Acceptability of Insurers
Insurance is to be placed with insurers authorized to conduct business in the state with a current A.M. Best’s rating of no less than A:VII, unless otherwise acceptable to the City of Sebastopol.

However, failure to obtain the required documents prior to the work beginning shall not waive the Consultant’s obligation to provide them. The City of Sebastopol reserves the right to require complete, certified copies of all required insurance policies, including endorsements required by these specifications, at any time.

Subcontractors
Consultant shall require and verify that all subcontractors maintain insurance, meeting all the requirements stated herein, and Contractor shall ensure that the City of Sebastopol is an additional insured on insurance required from subcontractors.

Special Risks or Circumstances
The City of Sebastopol reserves the right to modify these requirements, including limits, based on the nature of the risk, prior experience, insurer, coverage, or other special circumstances.

SECTION 8 – INDEMNIFICATION
A. Consultant shall indemnify and hold harmless City, its agents, officers, officials, employees, and volunteers from any and all claims, demands, suits, loss, damages, injury, and/or liability (including any and all costs and expenses in connection therewith), incurred by reason of any negligent or otherwise wrongful act or omission of Consultant, its officers, agents, employees and subcontractors, or any of them, under or in connection with this Agreement; and Consultant agrees at its own cost, expense and risk to defend any and all claims, actions, suits, or other legal proceedings Agenda Item Number 3
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City of Sebastopol Agreement for Professional Services Page 5 of 10 brought or instituted against City, its agents, officers, officials, employees and volunteers, or any of them, arising out of such negligent or otherwise wrongful act or omission, and to pay and satisfy any resulting judgments.

B. When Consultant under this Agreement is duly licensed under California Business and Professions Code as an architect, landscape architect, professional engineer, or land surveyor (“design professional”), the provisions of this section regarding Consultant’s duty to defend and indemnify apply only to claims that arise out of or relate to the negligence, recklessness, or willful misconduct of the design professional.

C. If any action or proceeding is brought against Indemnitees by reason of any of the matters against which Consultant has agreed to indemnify Indemnitees as provided above, Consultant, upon notice from City, shall defend Indemnitees at Consultant’s expense by counsel acceptable to City, such acceptance not to be unreasonably withheld. Indemnitees need not have first paid for any of the matters to which Indemnitees are entitled to Indemnification in order to be so indemnified. The insurance required to be maintained by Consultant shall ensure Consultant’s obligations under this section, but the limits of such insurance shall not limit the liability of Consultant hereunder. The provisions of this section shall survive the expiration or earlier termination of this Agreement.

The provisions of this section do not apply to claims to the extent occurring as a result of the City’s sole negligence or willful acts or misconduct.

SECTION 9 – INDEPENDENT CONTRACTOR STATUS
A. Consultant is and shall at all times remain a wholly independent contractor and not an officer, employee, or agent of City. Consultant shall have no authority to bind City in any manner, nor to incur an obligation, debt or liability of any kind on behalf of or against City, whether by contract or otherwise, unless such authority is expressly conferred under this Agreement or is otherwise expressly conferred in writing by City.

B. The personnel performing the services under this Agreement on behalf of Consultant shall at all times be under Consultant’s exclusive direction and control. Neither City, nor any elected or appointed boards, officers, officials, employees or agents of City, shall have control over the conduct of Consultant or any of Consultant’s officers, employees or agents, except as set forth in this Agreement. Consultant shall not at any time or in any manner represent that Consultant or any of Consultant’s officers, employees or agents are in any manner officials, officers, employees or agents of City.

C. Neither Consultant, nor any of Consultant’s officers, employees or agents, shall obtain any rights to retirement, health care or any other benefits which may otherwise accrue to City’s employees.

Consultant expressly waives any claim Consultant may have to any such rights.

SECTION 10 – CONFLICTS OF INTEREST
A. Consultant covenants that neither it, nor any officer or principal of its firm, has or shall acquire any interest, directly or indirectly, which would conflict in any manner with the interests of City or which would in any way hinder Consultant’s performance of services under this Agreement.

Consultant further covenants that in the performance of this Agreement, no person having any such interest shall be employed by it as an officer, employee, agent, or subcontractor without the express Agenda Item Number 3
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City of Sebastopol Agreement for Professional Services Page 6 of 10 written consent of the City Manager. Consultant agrees to at all times avoid conflicts with the interests of City in the performance of this Agreement.

B. City understands and acknowledges that Consultant is, as of the date of execution of this Agreement, independently involved in the performance of non-related services for other governmental agencies and private parties. Consultant is aware of any stated position of City relative to such projects.

Any future position of City on such projects shall not be considered a conflict of interest for purposes of this section.

SECTION 11 – OWNERSHIP OF DOCUMENTS
A. All original maps, models, designs, drawings, photographs, studies, surveys, reports, data, notes, computer files, files and other documents prepared, developed or discovered by Consultant in the course of providing any services pursuant to this Agreement shall become the sole property of City and may be used, reused or otherwise disposed of by City without the permission of the Consultant.

When requested by City, but no later than three years after project completion, Consultant shall deliver to City all such original maps, models, designs, drawings, photographs, studies, surveys, reports, data, notes, computer files, files and other documents.

B. All copyrights, patents, trade secrets, or other intellectual property rights associated with any ideas, concepts, techniques, inventions, processes, improvements, developments, works of authorship, or other products developed or created by Consultant during the course of providing services (collectively the “Work Product”) shall belong exclusively to City. The Work Product shall be considered a “work made for hire” within the meaning of Title 17 of the United States Code.

Without reservation, limitation, or condition, Consultant hereby assigns, at the time of creation of the Work Products, without any requirement of further consideration, exclusively and perpetually, any and all right, title, and interest Consultant may have in the Work Product throughout the world, including without limitation any copyrights, patents, trade secrets, or other intellectual property rights, all rights of reproduction, all rights to create derivative works, and the right to secure registrations, renewals, reissues, and extensions thereof.

SECTION 12 – CONFIDENTIAL INFORMATION; RELEASE OF INFORMATION A. All information gained or work product produced by Consultant in performance of this Agreement shall be considered confidential, unless such information is in the public domain or already known to Consultant. Consultant shall not release or disclose any such information or work product to persons or entities other than City without prior written authorization from the City Manager, except as may be required by law.

B. Consultant, its officers, employees, agents or subcontractors, shall not, without prior written authorization from the City Manager or unless requested by the City Attorney of City, voluntarily provide declarations, letters of support, testimony at depositions, response to interrogatories or other information concerning the work performed under this Agreement. Response to a subpoena or court order shall not be considered “voluntary” provided consultant gives City notice of such court order or subpoena.

C. If Consultant, or any officer, employee, agent, or subcontractor of Consultant, provides any information or work product in violation of this Agreement, then City shall have the right to reimbursement and indemnity from Consultant for any damages, costs and fees, including attorney’s fees, caused by or incurred as a result of Consultant’s conduct.

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City of Sebastopol Agreement for Professional Services Page 7 of 10 D. Consultant shall promptly notify City should Consultant, its officers, employees, agents or subcontractors be served with any summons, complaint, subpoena, notice of deposition, request for documents, interrogatories, request for admissions or other discovery request, court order or subpoena from any party regarding this Agreement and the work performed thereunder. City retains the right, but has no obligation, to represent Consultant or be present at any deposition, hearing or similar proceeding. Consultant agrees to cooperate fully with City and to provide City with the opportunity to review any response to discovery requests provided by Consultant. However, this right to review any such response does not imply or mean the right by City to control, direct, or rewrite such response.

SECTION 13 – SUSPENSION OF WORK
City may, at any time, by ten (10) days written notice suspend further performance by Consultant. All suspensions shall extend the time schedule for performance in a mutually satisfactory manner and Consultant shall be paid for services performed and reimbursable expenses incurred prior to the suspension date.

SECTION 14 – COMPLIANCE WITH LAW
Consultant shall keep itself informed of and comply with all applicable federal, state and local laws, statutes, codes, ordinances, regulations and rules in effect during the term of this Agreement.

Consultant shall obtain any and all licenses, permits and authorizations necessary to perform the services set forth in this Agreement. Neither City, nor any elected or appointed boards, officers, officials, employees or agents of City, shall be liable, at law or in equity, as a result of any failure of Consultant to comply with this section.

SECTION 15 – COMPLIANCE WITH CIVIL RIGHTS
During the performance of this contract, Consultant agrees as follows:

A. Equal Employment Opportunity. In connection with the execution of this Agreement, Consultant shall not discriminate against any employee or applicant for employment because of race, religion, color, ancestry, age, sexual orientation, physical handicap, medical condition, marital status, sex, or national origin. Such actions shall include, but not be limited to, the following: employment, promotion, upgrading, demotion, or transfer; recruitment or recruitment advertising; layoff or termination; rate of pay or other forms of compensation; and selection for training including apprenticeship.

B. Nondiscrimination Civil Rights Act of l964. Consultant will comply with all federal regulations relative to nondiscrimination to federally-assisted programs.

C. Solicitations for Subcontractors including Procurement of Materials and Equipment. In all solicitations, either by competitive bidding or negotiations, made by Consultant for work to be performed under a subcontract, including procurement of materials or leases of equipment, each potential subcontractor, supplier, or lessor shall be notified by Consultant of Consultant’s obligations under this Agreement and the regulations relative to nondiscrimination.

SECTION 16 – RECORDS
A. Records of Consultant’s direct labor costs, payroll costs, and reimbursable expenses pertaining to this project covered by this Agreement will be kept on a generally recognized accounting Agenda Item Number 3
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City of Sebastopol Agreement for Professional Services Page 8 of 10 basis and made available to City if and when required for a period of up to 3 years from the date of Consultant’s final invoice.

B. Consultant’s records and design calculations will be available for examination and audit if and as required. The cost of any reproductions shall be paid by City.

SECTION 17 – COOPERATION BY CITY
All public information, data, reports, records, and maps as are existing and available to City as public records, and which are necessary for carrying out the work as outlined in the Exhibit A, “Scope of Services”, shall be furnished to Consultant in every reasonable way to facilitate, without undue delay, the work to be performed under this Agreement.

SECTION 18 – NOTICES
All notices required or permitted to be given under this Agreement shall be in writing and shall be personally delivered, or sent by facsimile or first class mail, addressed as follows:

To City: City Manager
7120 Bodega Ave
Sebastopol, California 95472
To Consultant: Luhdorff & Scalmanini Consulting Engineers 500 1st Street
Woodland, CA 95695

Notice shall be deemed effective on the date personally delivered or transmitted by facsimile, or, if mailed, three (3) days after deposit in the custody of the U.S. Postal Service.

SECTION 19 – TERMINATION
City may terminate this Agreement, with or without cause, at any time by giving ten (10) days written notice of termination to Consultant. If such notice is given, Consultant shall cease immediately all work in progress.

If either Consultant or City fail to perform any material obligation under this Agreement, then, in addition to any other remedies, either Consultant, or City may terminate this Agreement immediately upon written notice.

Upon termination of this Agreement by either Consultant or City, all property belonging to City which is in Consultant’s possession shall be delivered to City. Consultant shall furnish to City a final invoice for work performed and expenses incurred by Consultant, prepared as set forth in this Agreement.

SECTION 20 – ATTORNEY FEES
If litigation or other proceeding is required to enforce or interpret any provision of this Agreement, the prevailing party in such litigation or other proceeding shall be entitled to an award of reasonable attorneys’ fees, costs and expenses, in addition to any other relief to which it may be Agenda Item Number 3
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City of Sebastopol Agreement for Professional Services Page 9 of 10 entitled. In addition, any legal fees, costs and expenses incurred to enforce the provisions of this Agreement shall be reimbursed to the prevailing party.

SECTION 21 – ENTIRE AGREEMENT
This Agreement, including the attached Exhibits, is the entire, complete, final and exclusive expression of the parties with respect to the matters addressed therein and supersedes all other agreements or understandings, whether oral or written, or entered into between Consultant and City prior to the execution of this Agreement. No statements, representations or other agreements, whether oral or written, made by any party which are not embodied herein shall be valid and binding unless in writing duly executed by the parties or their authorized representatives.

SECTION 22 – SUCCESSORS AND ASSIGNS
This Agreement shall be binding on the heirs, executors, administrators, successors and assigns of the parties. However, this Agreement shall not be assigned by Consultant without written consent of the City.

SECTION 23 – CONTINUITY OF PERSONNEL
Consultant shall make every reasonable effort to maintain the stability and continuity of Consultant’s staff assigned to perform the services required under this Agreement. Consultant shall notify City of any changes in Consultant’s staff assigned to perform the services required under this Agreement, prior to any such performance.

SECTION 24 – DEFAULT
In the event that Consultant is in default under the terms of this Agreement, the City shall not have any obligation or duty to continue compensating Consultant for any work performed after the date of default and may terminate this Agreement immediately by written notice to Consultant.

SECTION 25 – WAIVER
Waiver by any party to this Agreement of any term, condition, or covenant of this Agreement shall not constitute a waiver of any other term, condition, or covenant. Waiver by any party of any breach of the provisions of this Agreement shall not constitute a waiver of any other provision, nor a waiver of any subsequent breach or violation of any provision of this Agreement. Acceptance by City of any work or services by Consultant shall not constitute a waiver of any of the provisions of this Agreement.

SECTION 26 – LAW TO GOVERN; VENUE
This Agreement shall be interpreted, construed and governed according to the laws of the State of California. In the event of litigation between the parties, venue in state trial courts shall lie exclusively in the County of Sonoma. In the event of litigation in a U.S. District Court, venue shall lie exclusively in the Northern District of California, in San Francisco.

Agenda Item Number 3
Agenda Item Number 3
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City of Sebastopol Agreement for Professional Services Page 10 of 10 SECTION 27 – SEVERABILITY
If any term, condition or covenant of this Agreement is declared or determined by any court of competent jurisdiction to be invalid, void or unenforceable, the remaining provisions of this Agreement shall not be affected thereby and the Agreement shall be read and construed without the invalid, void or unenforceable provision(s).

SECTION 28 – SPECIAL PROVISIONS
This Agreement is subject to the following special provisions: none.

IN WITNESS WHEREOF, the parties hereto have accepted, made, and executed this Agreement upon the terms, conditions, and provisions above stated, the day and year first above written.

City: Consultant:

Luhdorff & Scalmanini
Consulting Engineers
By: By:

Name: Mary Gourley Date Name: Scott Lewis Date
Title: Interim City Manager Title: President
Approved as to Form:

By:

Name: Alex Mog Date
Title City Attorney
Agenda Item Number 3
Agenda Item Number 3
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February 25, 2026 Project No. 25-2-196
Oriana Hart, Public Works Director
City of Sebastopol
Public Works Department
714 Johnson Street
Sebastopol, CA 95472
SUBJECT: Updated Scope of Work and Budget – City of Sebastopol Well 4 Replacement (CIP #0822-24.06)
Dear Ms. Hart,
Pursuant to discussions between Luhdorff and Scalmanini Consulting Engineers (LSCE) and the City of Sebastopol (City), LSCE has prepared this updated scope of work and budget estimate to provide hydrogeologic and engineering support services for the City’s Well 4 Replacement Project. The proposed services are intended to support the planning, design, permitting, funding assistance, and bid-phase support for a replacement municipal supply well that will provide a reliable and sustainable long-term water source for the City. This updated scope and budget reflect LSCE’s current understanding of project needs, anticipated technical requirements, and coordination with City staff and applicable regulatory agencies.

DETAILED SCOPE OF WORK
LSCE has reviewed and understands the project as outlined in the City’s RFP. The Scope of Work outlined in the tasks below encompasses all the core objectives outlined in the RFP and discussions with the City.

Phase 1
Task 1 – Project Coordination, Meetings, and Administration Task 1.1 – Kickoff and Information Request
LSCE’s work on the project will begin with a kickoff meeting with City staff and key LSCE team members to discuss the various aspects of the project. Items such as contact information, chain of command, the City’s project expectations, respective roles and responsibilities, schedule, design preferences and parameters, and site constraints shall be discussed at the kick-off meeting. Following the meeting, LSCE will provide the City with a list of requested information. 500 First Street, Woodland, CA 95695 • Tel. 530.661.0109 • Fax. 530.661.6806 • lsce.com

EXHIBIT A
Agenda Item Number 3
Agenda Item Number 3
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Task 1.2 - Project Coordination, Meetings, and Administration Key LSCE team members will attend regular design meetings with the City to discuss various aspects of the project. For each meeting, LSCE will prepare and distribute meeting agendas, minutes, and summaries of action items. LSCE will also provide frequent updates via email, telephone, or web-based meeting platforms as needed throughout the project. This task also provides project management and administrative activities such as: (a) Contractual Arrangements, (b) Ongoing Examination Regarding Adherence to The Scope, Budget, and Schedule, (c) Coordination of Staff Resources (d) Internal Review of Work Products, (e) Management of Subcontractors, (f) Billing Review, and (g) Scoping and Budgeting.

Task 2 – Funding Assistance
LSCE will assist the City with preparing and submitting a DWSRF funding application, including assembling technical documentation, schedules, preliminary cost estimates, and environmental compliance materials.

TASK 2.1 – DWSRF Construction Funding Application
LSCE will coordinate with the City to incorporate the needed information and data for the proposed Project to complete the DWSRF Construction Funding Application. The Project scope of work, budget, and schedule will be developed in coordination with the City, consistent with the 2025 DWSRF Construction Funding Program guidelines. LSCE will prepare and submit the required DWSRF Construction Funding Application documents, including the application elements, as follows:
• General Package - DWSRF Construction Funding Application Package • Technical Package - DWSRF Construction Funding Application Package (100% design) • Environmental Package - DWSRF Construction Funding Application Package (CEQA-Plus) • Financial Package - DWSRF Construction Funding Application Package The application elements above will be developed based on information provided by the City. LSCE will develop a comprehensive DWSRF construction funding application, which will contain the four packages outlined above.

LSCE will develop the Project Report required as part of the Technical Package submittal and will incorporate the 100% plans and specifications prepared under Tasks 4 and 5 into the Project Report, as required for a complete DWSRF funding application.

LSCE will submit a draft of the completed DWSRF Construction Funding Application packages to the City for review and comment before submitting the final application. Comments from the City will be incorporated into the final application submitted to the SWRCB.

LSCE will submit the completed DWSRF Construction Funding Application through the SWRCB’s online FAAST process. The process of receiving funding approval is anticipated to occur in the fourth quarter of 2026. The funding agency will review applications in 2027, subject to their schedule for processing other funding applications. LSCE will work with the funding agency to submit a complete application and to help coordinate a timely decision for funding approval.

Agenda Item Number 3
Agenda Item Number 3
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Task 2.2 – DWSRF Environmental Documentation
This task involves preparing the minimum CEQA-Plus requirements outlined in the DWSRF funding policy.

This would involve preparing Cultural and Biological Resource Assessments that meet both federal and state environmental requirements. It is LSCE’s experience that, at a minimum, these assessments are required for all DWSRF construction applications and must be completed as part of the application approval process. These are in addition to the proposed CEQA compliance documentation for a well replacement, which typically involves preparing and filing a Notice of Exemption. Any additional CEQAPlus or other compliance documentation required, beyond that described above, would be prepared through an additional task order as agreed upon between the parties. It has been LSCE’s experience that the DWSRF funding program often requires the most stringent environmental documentation and processes compared to other funding options. If the DWSRF financing option is not pursued, this task will not be required, and the funds allocated for it can instead be applied toward alternative funding procurement under Task 6.3.

Task 2.3 – Alternate Funding Sources (Optional)
LSCE can also assist the City with the identification of alternate funding opportunities and the City’s eligibility for identified funding sources. If the City chooses to pursue an alternative funding source, LSCE would assist with the funding application procurement process and coordination with the funding agency.

Task 6.3(a) would involve reviewing the current City water project funding TM prepared by Hazen-Sawyer and preparing an updated TM that reviews other funding options and recommends best available funding sources to pursue in order to fund the proposed well replacement project in a timely manner.

The deliverables for this task include a draft Project Funding Technical Memorandum for City staff review and comment, followed by a final Project Funding Technical Memorandum suitable for inclusion in City files and for use on the project.

Task Budget = Task 6.3(a). = $ 5,000
Under Task 6.3(b), LSCE will assist the City with the preparation and submittal of recommended best available funding source application and document submittal to the funding agency for review and approval. LSCE will coordinate and collaborate with the funding agency to facilitate funding approval and provide assistance with funding agreement execution.

Task Budget = Task 6.3(b). = $20,175
Note that Task 6 budget is adjusted for elimination of $23,000 budget to prepare DWSRF funding (Tasks

6.1 and 6.2) application assuming the City selects a different funding source that is recommended in the Final Project Funding TM.

Task 3 – Permitting Assistance
Task 3.1 – Permitting Assistance
Through our work on numerous projects in the past, LSCE has developed a good working relationship with the SWRCB and other regional permitting and regulatory entities and can assist in expediting all necessary Agenda Item Number 3
Agenda Item Number 3
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applications and supporting permit documents in a cost-efficient manner. LSCE envisions that the following permitting activities will be required to complete the project.

SWRCB-DDW Water Supply Permit Amendment – LSCE will coordinate with the SWRCB-DDW and the City to provide all necessary supporting technical information to complete the water supply permit amendment package, which will be submitted to the SWRCB-DDW. LSCE has completed numerous new and amended water supply permits and has a thorough understanding of the SWRCB-DDW process and the required submittals. A draft watersupply amendment will be submitted to the SWRCB-DDW following construction of the production well. Following the completion and acceptance of the project, LSCE will assist the City with the preparation of the final DDW amended water supply permit, which will include updates to the information from the preliminary submittal and the submission of the final As-Built drawings prepared by LSCE.

CEQA – LSCE envisions that the project meets the requirements for a CEQA categorical exemption. LSCE will prepare CEQA documentation consistent with a Class 1 or Class 3 Categorical Exemption, including drafting the exemption form, providing supporting technical rationale, coordinating with City Planning staff, and assisting the City in filing the Notice of Exemption.

Other Permitting Activities – LSCE will contact applicable agencies as needed to establish permitting requirements for well drilling (County of Sonoma), well siting concurrence (Division of Drinking Water), encroachment permits(City), and discharge requirementsfor development and pump testing fluids(City).

Task 4 – Site Specific Investigation
Task 4.1 – Initial Site Assessment
Well Siting Review – LSCE will complete a thorough onsite inspection/assessment of the site. Specifically, LSCE will evaluate the well site in relation to the siting and constructability of the new well, as well as the DDW setback distances from sanitary features and control zone requirements.

Hydrogeologic Review – The goal of the hydrogeologic review is to determine the probable yield, water quality, anticipated well depth, screen intervals, static and pumping water levels, specific capacity, and potential impacts on nearby wells due to the pumping of the new well.

Evaluation of Potential Impacts to Groundwater Quality – LSCE will investigate possible sources of groundwater contamination in the vicinity of the project site.

Task 4.2 – Test Hole and Monitoring Well
Task 3.2 will include test hole drilling and installation of a nested monitoring well. A test hole will be drilled to collect lithologic samples for analysis and to conduct a downhole geophysical survey that will be used to evaluate subsurface materials and to design a new production well. Based on the results of test hole drilling and geophysical logging, two to three nested casings will be constructed within the test hole. The nested monitoring well will allow for the collection of zone-specific water levels and water quality samples. A preliminary test hole depth of 550 feet, based on LSCE’s initial data review, was used for the purposes of the project cost estimation. LSCE will provide subcontracted test hole drilling services from a licensed drilling contractor and will oversee the work to ensure that it is performed in accordance with Agenda Item Number 3
Agenda Item Number 3
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ourstringent specifications and high expectations. The selected drilling contractor will be required to fully contain and take possession of all drilling fluids and cuttings generated during the project and properly dispose of them offsite. LSCE will ensure that all necessary permits to perform the work will be secured.

LSCE will provide documentation and sampling services during the drilling process, including preparation of a lithologic log, inspection of drilling cuttings at a minimum of 10-foot of borehole advanced, interpretation of geophysical (electric) logs, and grain size distribution analysis ofselected samples. Based on the borehole investigation, LSCE will prepare a monitoring well design. A typical nested monitoring site may include up to three, 2-inch-diameter polyvinyl chloride (PVC) monitoring wells, completed in different zones. The screen section(s) of each monitoring well will be isolated from one another using intermediate bentonite seals, allowing for discrete water level measurements and water quality sampling. LSCE will oversee the construction and development of the nested monitoring well.

Task 4.3 – Monitoring Well Sampling
Task 3.3 includes sampling of the nested monitoring well. LSCE will provide technicians and equipment to purge and sample each monitoring well casing. Each casing will be purged before sampling to ensure that the well is fully purged and that representative formation water is being pumped from the monitoring well. LSCE will deliver the samples to a certified ELAP state-certified laboratory. The water quality analysis will include Title 22 Drinking Water constituents and other constituents of concern, including PFAS compounds. The results of the water quality laboratory analysis will be tabulated in a water quality summary table for inclusion in the Task 3.4 deliverable.

Task 4.4 – Well Design Recommendation Report
LSCE will prepare and deliver to the City an Investigation Summary and Preliminary Well Design Report that will summarize the findings of the site assessment and site characterization work performed as part of Tasks 3.2 and 3.3. The report will include:
• A summary of all field activities associated with test hole drilling, monitoring well construction and development, and water quality sampling purge logs
• A lithologic log based upon interpretation of collected lithologic samples and the geophysical log • Geophysical log
• Grain size distribution chart ofselected formation samples • Monitoring well as-built diagram
• Daily inspection sheets
• A summary of water quality results and laboratory analytical report • Copies of all project permits
• Copy of the Well Completion Report
LSCE will prepare a site-specific preliminary production well design based on data gathered during test hole and monitoring well evaluation, and our experience in the area. The principal design elements to achieve a hydraulically efficient and sand-free well include:

Agenda Item Number 3
Agenda Item Number 3
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• Borehole and casing depths and
diameters
• Casing and screen wall thickness
• Gravel pack gradation
• Screen slot size
• Casing material type(s)
• Screen intervals
• Screen type and material
• Seal depths
• Accessory pipe depth, material, and
diameter
The report will include a drafted preliminary well design profile. The design elements of the well and yield estimation will be discussed in the report. A preliminary engineer’s estimate for the construction and testing of the well will be included in the report. LSCE will meet with the City to discuss the results and findings of the test hole/monitoring well investigation and new well design recommendations. LSCE will incorporate the City’s design comments into the final well design.

Task 4.5 – Siting Concurrence
After the City approves the well design, LSCE will prepare an initial DDW submittal document requesting siting and design concurrence for the new well, based on compliance with DDW and DWR regulations.

The initial submittal will include a preliminary well design, site layout, location map indicating location and distances of sanitary features from the proposed well location, delineation of the wellhead control zone, and a preliminary DWSAP.

Phase 2
Task 5 – Production Well Final Design
Task 5.1 – Production Well Construction Specifications
LSCE will prepare specifications that include detailed construction requirements to be followed by the well drilling contractor during every phase of the project, including minimum acceptable methods for drilling fluid control, well development, pump testing, and well performance standards. Othersite-specific items will include requirements for the containment and disposal of drill cuttings, as well as the handling of discharge water during development and test pumping, in accordance with applicable local, state, and federal regulations. The production well specifications will include comprehensive design plans, accompanied by an engineer’s cost estimate for the City’s use.

LSCE will attend up to two regulatory coordination meetings with SWRCB-DDW and the Water Board, supporting the City with technical presentations and responding to regulator questions related to siting, well design, and water supply permit amendments under this task.

LSCE will also support one public outreach meeting under this task by preparing presentation materials, summarizing technical content in accessible formats, and attending meetings with City staff to respond to community questions related to well siting, design, construction sequencing, and water-quality considerations.
500 First Street, Woodland, CA 95695 • Tel. 530.661.0109 • Fax. 530.661.6806 • lsce.com Ms. Hart
February 2026

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Agenda Item Number 3
Agenda Item Number 3
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LSCE will provide comprehensive bidding support and bid recommendation services, including preparation of bid documents, assistance during the bidding period, responses to contractor questions, and evaluation of submitted bids for completeness, responsiveness, and overall value. LSCE will review the qualifications and proposed costs of each bidder and provide a recommendation to the City to support selection of the most qualified and cost-effective contractor for the project.

Task 6 – Pump Station Final Design
Task 6.1 – Preliminary Pump Station Design Activities
LSCE will meet with and conduct a site visit with City personnel to discuss the overall pump station project design requirements, construction concepts, and site constraints at the existing site. The primary goal of the site visit is to discuss the design elements required to serve the new facility, including water supply connection, storm drain pump-to-waste (overboard) operations, building sewer systems, electrical services, radio communications, access controls, and other relevant aspects. To aid in this preliminary design effort, LSCE will distribute a design basis checklist documentto the City, enabling it to quickly obtain a comprehensive understanding of the City’s preferences for the functionality, operation, and equipment to be designed.

The LSCE Team will complete a topographic survey basemap in AutoCAD format for the project site. The basemap will be used for the preliminary layout of the pump station, which will, in turn, be used for preparing the final bid set plans. LSCE will incorporate City-provided standard plans, as-builts, and base mapping (as available) into the design process to ensure consistency with existing infrastructure. It is assumed that an existing geotechnical site investigation/study is available from the City for purposes of facilitating the overall project design, including structural foundation and building design elements.

Under this task, LSCE will also develop a Preliminary Design Report (PDR). The report will summarize design criteria, site constraints, and key assumptions established during early coordination with the City.

It will present preliminary layouts for the building, site civil improvements, process piping, electrical systems, and instrumentation. The report will also include an evaluation of the City-furnished pump equipment for compatibility with well performance data, along with any recommended adjustments to accommodate the equipment within the pump station design. Additionally, the PDR will outline anticipated permitting needs, identify any remaining data gaps, and provide a preliminary engineer’s estimate of probable construction cost. The document will serve as the basis for the development of the initial 50% design submittal (as part of Task 5.2) and will confirm alignment between LSCE and the City on scope, configuration, and design direction before advancing into detailed design.

Task 6.2 – Pump Station Design and Construction Specifications This task covers the scope of work required to prepare the engineering plans and technical specifications for the project, consisting of a well pump and motor, motor control center, discharge piping, chemical treatment system, instrumentation, electrical control panels, SCADA communication, a wood-framed building to house the above-ground components onsite, and all other required site improvements. The design will also address all other site modifications and improvements, including grading, drainage, paving, fencing, painting, etc. Following submittal of the PDR, the detailed design will be completed at the 50% and 100% stages, and an Engineer’s Estimate of project construction costs will be prepared with each Agenda Item Number 3
Agenda Item Number 3
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design phase. After the City’s review of each design phase, LSCE will prepare the complete set of plans and specifications for the subsequent design stage, incorporating any comments received from the City in the previous design reviews.

LSCE will attend up to two regulatory coordination meetings with SWRCB-DDW and the Water Board to obtain approval for the well pump station plans, the water supply permit amendment, and to coordinate field visits during project startup.

LSCE will also support one public outreach meeting under this task by preparing presentation materials, summarizing technical content in accessible formats, and attending follow-up meetings with City staff to respond to community questions related to the well pump station design and construction scope.

FEE ESTIMATE
LSCE’s estimated cost to complete the scope of work outlined in this proposal is based on our current understanding of the project and what would be typically expected to complete the tasks described based on our prior experience. The cost estimate assumes the following:
• A project design duration of 11-16 months.
• General Conditions, Supplemental General Conditions, and other “front-end” specifications will be prepared by the City.
• Design documents will conform to the City’s standards. • Construction-related costs are not included.
• Any additional environmental requirements beyond a Notice of Exemption (Task 2) and Cultural and Biological Resource Assessments (Task 6.2), are not included in the cost estimate Table 1 summarizes the project cost estimate by task. Attached is a detailed project cost estimate, including hours per LSCE task and subtask, billing rate by employee classification, estimated subconsultant costs, and miscellaneous expenses. LSCE will invoice monthly for labor, subcontracted services, and direct costs only as incurred, in accordance with our 2026 Schedule of Fees for Engineering and Field Services, which is included below.

Fees shall remain in effect for the full contract period. In the event that the City directs LSCE to deviate from the proposed scope, or as dictated by unforeseen field conditions or events beyond LSCE’s control, LSCE will provide notification of any potential changes in the estimated cost to complete the work. LSCE will not proceed with any work that deviates from the approved scope and budget until approval to proceed is granted by the City.

Agenda Item Number 3
Agenda Item Number 3
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Table 1. Estimated Project Budget Summary
Task LevelOf Effort
(hours)
Estimated
Budget(dollars)
Phase 1 – Preliminary Design
Task 1. Project Coordination, Meetings, and Administration 89 $22,795 Task 2. Funding Assistance* 95 $25,175
Task 3. Permitting Assistance 26 $16,185
Task 4. Site Specific Investigation 258 $313,940
Phase 1 Total Not to Exceed $378,095
Phase 2 – Final Design and Bid Support
Task 1. Project Coordination, Meetings, and Administration 89 $22,795 Task 5. Production Well Design 40 $8,490
Task 6. Pump Station Design 648 $230,169
Total Project Hours and Budget 1,245 $639,549
*Assumes Alternative funding approach to DWSRF will be pursued. Cost of this Task if DWSRF funding is pursued is $44,200.

SCHEDULE
LSCE’s proposed schedule is based on the tasks outlined in this scope of work, with an anticipated project completion date of January 2027.

We appreciate the opportunity to provide the City with this updated scope and budget. We will be happy to respond If you have any questions regarding either.

Sincerely,
Luhdorff & Scalmanini
Consulting Engineers
Charlie Jenkins, P.G. Scott Lewis, P.G.

Senior Geologist Senior Principal Geologist | President Attachments:

Detailed Cost Estimate
2026 Schedule of Fees for Engineering and Field Services Project Schedule
Agenda Item Number 3
Agenda Item Number 3
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Client City of Sebastopol
Project Well 4 Replacement
Job No. 25-2-196
Est. By CJ, OS
Date 2/25/2026
Senior Principal
Professional
Supervising
Professional
Senior
Professional
Staff
Professional Prevailing Wage Clerical Water Quality Bradley and Sons (Drilling)
Frisch
(Electrical)
Dokken
(CEQA)
PASE
(Structural)
Raney
(Geotech)
Phelps
(Surveying) Direct Expenses
Task Description $300 $265 $235 $185 $230 $115 Incurred Incurred Incurred Incurred Incurred Incurred Incurred Incurred Task Hours 6 8 6 8 0 0 28
Task Cost $1,800 $2,120 $1,410 $1,480 $0 $0 $6,810
SubTotal $1,800 $2,120 $1,410 $1,480 $0 $0 $6,810
Task Hours 12 29 20 0 0 0 0
Task Cost $3,600 $7,685 $4,700 $0 $0 $0 $15,985
SubTotal $3,600 $7,685 $4,700 $0 $0 $0 $15,985
$22,795
Task Hours 80 80
Task Cost $0 $21,200 $0 $0 $0 $0 $21,200
SubTotal $0 $21,200 $0 $0 $0 $0 $21,200
Task Hours 0 0
Task Cost $0 $0 $0 $0 $0 $0 $0
Outside Services $23,000 $23,000
SubTotal $0 $0 $0 $0 $0 $0 $23,000
Task Hours 95 95
Task Cost $0 $25,175 $0 $0 $0 $0 $25,175
Outside Services $0
SubTotal $0 $25,175 $0 $0 $0 $0 $25,175
$69,375
Task Hours 4 6 4 12 0 0 26
Task Cost $1,200 $1,590 $940 $2,220 $0 $0 $5,950
Outside Services $10,235 $10,235
SubTotal $1,200 $1,590 $940 $2,220 $0 $0 $16,185
$16,185
Task Hours 8 0 16 24 0 0 48
Task Cost $2,400 $0 $3,760 $4,440 $0 $0 $10,600
SubTotal $2,400 $0 $3,760 $4,440 $0 $0 $10,600
Task Hours 4 0 16 24 60 0 104
Task Cost $1,200 $0 $3,760 $4,440 $13,800 $0 $23,200
Outside Services $239,600 $239,600
SubTotal $1,200 $0 $3,760 $4,440 $13,800 $0 $262,800
Task Hours 2 0 4 12 24 0 42
Task Cost $600 $0 $940 $2,220 $5,520 $0 $9,280
Outside Services $18,000 $18,000
SubTotal $600 $0 $940 $2,220 $5,520 $0 $27,280
Task Hours 8 0 4 24 0 4 40
Task Cost $2,400 $0 $940 $4,440 $0 $460 $8,240
SubTotal $2,400 $0 $940 $4,440 $0 $460 $8,240
Task Hours 4 0 8 8 0 4 24
Task Cost $1,200 $0 $1,880 $1,480 $0 $460 $5,020
SubTotal $1,200 $0 $1,880 $1,480 $0 $460 $5,020
$313,940
Task Hours 6 8 6 8 0 0 28
Task Cost $1,800 $2,120 $1,410 $1,480 $0 $0 $6,810
SubTotal $1,800 $2,120 $1,410 $1,480 $0 $0 $6,810
Task Hours 12 29 20 0 0 0 0
Task Cost $3,600 $7,685 $4,700 $0 $0 $0 $15,985
SubTotal $3,600 $7,685 $4,700 $0 $0 $0 $15,985
$22,795
Task Hours 6 0 8 26 0 0 40
Task Cost $1,800 $0 $1,880 $4,810 $0 $0 $8,490
SubTotal $1,800 $0 $1,880 $4,810 $0 $0 $8,490
$8,490
Task Hours 0 48 0 88 0 4 140
Task Cost $0 $12,720 $0 $16,280 $0 $460 $29,460
Outside Services $11,500 $5,750 $4,198 $21,448
SubTotal $0 $12,720 $0 $16,280 $0 $460 $50,908
Task Hours 0 150 0 350 0 8 508
Task Cost $0 $39,750 $0 $64,750 $0 $920 $105,420
Outside Services $43,942 $29,900 $73,842
SubTotal $0 $39,750 $0 $64,750 $0 $920 $179,262
$230,169
Total LSCE Hours 72 453 112 584 84 20 1325
Total LSCE Cost $21,600 $120,045 $26,320 $108,040 $19,320 $2,300 $297,625 Outside Services $18,000 $239,600 $43,942 $33,235 $41,400 $5,750 $4,198 $386,124 $683,749
Task 1.2 – Project Coordination,
Meetings, and Administration
Task 1 – Project Coordination, Meetings, and Administration Summary
Task 6.2 – Pump Station Design
and Construction Specifications
Total Task Cost Estimate
Task 6 – Pump Station Final Design
Task 5 – Production Well Design
Cost Estimate for City of Sebastopol
for Well 4 Replacement
Total Task Cost Estimate
Task 3 – Permitting Assistance
Task 3.1 – Permitting
Assistance

SUMMARY
Task 5.1 – Production Well
Construction Specifications
Total Task Cost Estimate
Total Task Cost Estimate
Task 6.1 – Preliminary Pump
Station Design Activities
Total Cost Estimate
Task 1.1 – Kickoff and
Information Request
Task 4 – Site Specific Investigation
Total Task Cost Estimate
Task 4.1 – Initial Site
Assessment
Task 4.4 – Well Design
Recommendation Report
Task 4.5 – Siting Concurrence
Task 4.2 – Test Hole and
Monitoring Well
Task 4.3 – Monitoring Well
Sampling
Total Task Cost Estimate
Phase 1 - Preliminary Design
Phase 2 - Final Design and Bid Suppport
Task 2.3 – Alternative Funding
Sources (Optional)
Task 2 – Funding Assistance
Task 2.1 – Project Funding
Procurement-DWSRF
Task 2.2 – DWSRF
Environmental Documentation
Total Task Cost Estimate
Task 1 – Project Coordination, Meetings, and Administration Task 1.1 – Kickoff and
Information Request
Task 1.2 – Project Coordination,
Meetings, and Administration
Agenda Item Number 3
Agenda Item Number 3
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500 FIRST STREET • WOODLAND, CA 95695
Professional*
Senior Principal ............................................................................................ $300/hr.

Principal Professional................................................................................... $280/hr.

Supervising Professional.............................................................................. $265/hr.

Senior Professional ...................................................................................... $235/hr.

Project Professional ..................................................................................... $208/hr.

Staff Professional ......................................................................................... $185/hr.

Technical
Senior DMS/GIS Analyst…………………………………………………………………..……...$178/hr.

DMS/GIS.......................................................................................................$178/hr.

Engineering Assistant...................................................................................$148/hr.

Technician......................................................................................................... $148/hr.

Project Admin Support
Word Processing, Clerical............................................................................. $115/hr.

Digital Communications Specialist............................................................... $130/hr.

Project Admin/Accounting Assistant ........................................................... $130/hr.

Vehicle Use $0.70/mi (or curr. IRS rate)
Subsistence Cost Plus 15%
Groundwater Sampling Equipment(Includes Operator) $220.00/hr Copies $0.20 ea.

Professional or Technical Testimony 200% of Regular Rates Technical Overtime (if required) 150% of Regular Rates
Outside Services/Rentals Cost Plus 15%
Services by Associate Firms Cost Plus 15%
Prevailing Wage Rate $230/hr until June 30, 2026
Prevailing Wage Rate $235/hr after July 1, 2026
* Engineer, Geologist, Hydrogeologist, and Hydrologist
2026 SCHEDULE OF FEES

ENGINEERING AND RELATED FIELD SERVICES
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ID
Task Name Duration Start Finish
1 Council Approval 1 day Tue 3/17/26 Tue 3/17/262 Notice to Proceed 1 day Wed 3/18/26 Wed 3/18/263 TASK 1 - Project Coordination, Meetings, and Administration 11.05 mons Mon 3/23/26 Mon 1/25/274 Task 1.1 - Kickoff and Information Request 1 day Mon 3/23/26 Mon 3/23/265 Task 1.2 - Project Coordination, Meetings and Administration 11 mons Tue 3/24/26 Mon 1/25/276 TASK 2 - Funding Assistance 11 mons Tue 3/24/26 Mon 1/25/277 Task 2.1 - DWSRF Construction Funding Application 11 mons Tue 3/24/26 Mon 1/25/278 Task 2.2 - DWSRF Environmental Documentation 11 mons Tue 3/24/26 Mon 1/25/279 Task 2.3 - Alternate Funding Sources (Optional) 11 mons Tue 3/24/26 Mon 1/25/27 10 TASK 3 - Permitting Assistance 3 mons Tue 3/24/26 Mon 6/15/2611 Task 3.1 - Permitting Assistance 3 mons Tue 3/24/26 Mon 6/15/2612 TASK 4 - Site Specific Investigation 3 mons Tue 3/24/26 Mon 6/15/2613 Task 4.1 - Initial Site Assessment 0.3 mons Tue 3/24/26 Tue 3/31/2614 Task 4.2 - Test Hole and Monitoring Well 0.35 mons Wed 4/1/26 Thu 4/9/2615 Task 4.3 - Monitoring Well Sampling 0.35 mons Fri 4/10/26 Mon 4/20/2616 Task 4.4 - Well Design Recommendation Report 1 mon Tue 4/21/26 Mon 5/18/2617 Task 4.5 - Siting Concurrence 1 mon Tue 5/19/26 Mon 6/15/2618 TASK 5 - Production Well Design 1 mon Tue 6/16/26 Mon 7/13/2619 Task 5.1 - Production Well Construction Specifications 1 mon Tue 6/16/26 Mon 7/13/2620 TASK 6 - Pump Station Final Design 8 mons Tue 6/16/26 Mon 1/25/2721 Task 6.1 - Preliminary Pump Station Design Acitivities 2 mons Tue 6/16/26 Mon 8/10/2622 Task 6.2 - Pump Station Design and Construction Specifications 6 mons Tue 8/11/26 Mon 1/25/27 Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb
Qtr 2, 2026 Qtr 3, 2026 Qtr 4, 2026 Qtr 1, 2027
City of Sebastopol Well 4 Replacement
(Rev 2026)
1 of 1
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City of Sebastopol

REQUEST FOR STATEMENT OF QUALIFICATIONS / REQUEST FOR PROPOSALS

FOR ENGINEERING SERVICES FOR
WELL 4 REPLACEMENT (CIP #0822-24.06)
Proposal Due Date: December 1, 2025, 5:00 P.M.

Approved for Release:

November 3, 2025
Toni Bertolero, Public Works Engineer Date

PUBLIC WORKS DEPARTMENT
714 JOHNSON STREET
SEBASTOPOL, CA 95472
[email protected]
Phone: 707-823-2151
Addendum 1: Due date extended to December 8, 2025, 5:00 P.M.

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RFP – Well 4 Replacement Project Page 2 of 6

I) BACKGROUND
The City of Sebastopol is soliciting proposals from qualified engineering firms for the Well 4 Replacement Project CIP #0822-24.06 (Project). Well 4 is located at 710 Petaluma Avenue in Sebastopol at the intersection of Gravenstein Highway and Palm Avenue. Located on the site is a well and pump house, two vertical GAC filter vessels, including process piping, valving, sand removal equipment, and a filter backwash storage/buffer tank.

The well was drilled in 1953 to a depth of 530 feet has a 14-inch steel casing. The well pump is 100 horsepower (HP) vertical turbine pump enclosed within a pump house and rated for 900 gpm capacity. Additional information can be found in the report entitled Drinking Water Regulatory Compliance Feasibility Project, GHD Inc., November 2012 (see Appendix C).

This RFP is to provide engineering services for the Project as described in paragraph II below.

II) DESCRIPTION OF PROJECT
The Project consists of well drilling and development, well pump and VFD, well building, site work, yard piping, electrical, and controls. The City recently purchased a new pump. Rather than purchasing an additional pump for this replacement well, the City would like to use the one that was previously purchased in the design. This should be discussed further during the design phase.

The project will also include assistance with financing and/or grant funding of the construction of the Well 4 replacement. Additional information can found in the document entitled City of Sebastopol Well #4 Funding Evaluation Technical Memorandum, Hazen and Sawyer, June 30, 2025 (see Appendix D).

III) SCOPE
The selected Consultant must provide and identify an experienced project team who has successfully delivered services on similar projects. The general scope of services include:

Scope
• Project management
• Attending meetings with regulatory agencies such as the Water Board, Office of Drinking Water (up to 4)
• Preliminary design and preliminary cost estimate
• Final design and preparation of plans, specifications, and Engineer’s Estimate • Public presentation and outreach (up to 2 meetings)
• Assistance with financing or grant application
• Documentation and compliance, obtaining necessary permits, and ensuring all regulatory requirements are met
The Proposer shall include an Approach to the Work, and a Detailed Scope of Work in their Proposal.

IV) FEE ESTIMATE
A detailed breakdown of fees, by task, shall be provided in spreadsheet format.

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RFP – Well 4 Replacement Project Page 3 of 6

V) PRE-QUALIFICATION
If you are selected and your firm does not currently have a valid Master Services Agreement with the City, you will be required to enter into a Professional Services Agreement (see Appendix B).

Please review Standard Terms and Conditions in Section XII.

If your firm is selected and has a valid Master Services Agreement, you will not be required to enter into a Professional Services Agreement with the City, but will be contracted through a Task Order agreement and Purchase Order issued by the City.

VI) SCHEDULE
The Request for Proposals (RFP) was released on the date shown on the cover of this RFP. It is the City’s intent that this solicitation will be due on the date shown on the cover of this RFP.

Evaluation of proposals by the City will commence within thirty (30) days of receipt. The City reserves the right to conduct follow-up interviews with Proposer(s). A preliminary schedule of administrative milestones are listed below. The Consultant shall include a schedule in the Proposal that includes key milestones from date of the Notice to Proceed with the work through project completion.

Preliminary schedule:

Release of RFP See date on front cover
Proposals Due See date on front cover
Proposal Review/Selection 30 days from Proposal due date Council Approval January 20, 2025 (est)
Notice to Proceed Date when fully-signed contract is executed VII) CITY’S RESPONSIBILITIES
City will make available standard plans and details, standard contract documents, and general contract provisions for public works contracts for the consultant’s use, upon selection. City will also furnish PDF copies of existing City plans, base maps, and other background materials for consultant’s use as needed. If only hard-copy versions of the documents are available, a print copy will be provided, at Consultant’s costs.

VIII) GUIDELINES FOR PROPOSALS
a. Proposals should not exceed 15 pages in length, excluding cover letter, dividers, appendices, and summary resumes (no more than one page per person). b. Proposals must be signed by the individual who is authorized to execute the Professional Services Agreement or Task Order, should your firm be selected. c. Proposals shall include documentation demonstrating that the firm has contracted directly with public agencies located in California within the last five (5) years and successfully completed a minimum of three (3) projects of similar scope and size. d. Documentation for each referenced project included in your proposal shall include information in the format shown below:
1) Client Name
2) Project Name and Description, including if construction project was funded with federal aid grant funds
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RFP – Well 4 Replacement Project Page 4 of 6
3) Project Start and End Dates
4) Client Project Manager Name, Phone Number, and email address 5) Key Consultant team members including assigned project manager, Lead design engineer, and finance/grant specialist
e. Proposals shall include a summary section describing your understanding of and approach to the proposed project assignment identified in this RFP, and a detailed Scope of Work to complete the project.
f. Proposals shall include your firm’s general billing information as follows:
1) Schedule of hourly rates, including any special rates offered to public agencies, and prevailing wage rates as appropriate.
2) Travel-time charge-out policy (please see item #5 below). 3) Vehicle or equipment charge-out policy.
4) Percentage markup for reimbursable expenses.
5) Lodging expenses, meals, air fare, and other travel expenses (excluding vehicle mileage reimbursement) to and from Consultant’s Office to the job site are not allowed.

IX) PROCESS FOR SUBMITTING PROPOSALS
a. Proposals should focus on information requested above. Brochures and promotional materials should not be submitted with your proposal. b. Submit three (3) paper copies of proposal, one of which is unbound, in a sealed envelope addressed to:

Attn: Elissa Overton, Engineering Technician II
Sebastopol Public Works Department
714 Johnson Street
Sebastopol, CA 95472
RE: RFP for Well 4 Replacement Project
The Fee Estimate, as described in Section IV, shall accompany the Proposal. Proposals shall be submitted in person, or by mail, or delivery service by the due date stated on the front cover of this RFP. In addition to the paper copies, please submit a PDF copy of the Proposal (excluding the Fee Estimate) to [email protected]. Office hours for receipt of Proposals are:

Monday – Thursday, 7:30 a.m. – 5:00 p.m.

Offices are closed on state and federal holidays
A final Cost Proposal/Fee Estimate will be negotiated with the selected consultant.

X) QUESTIONS
Questions regarding this RFP or its requirements may be submitted, preferably by email, to:
[email protected]. Due to staffing constraints, the City will attempt to respond within two (2) business days of receipt (note Fridays are non-business days for the City). Your email question should include in the Subject Line: “Questions re. RFP for Well 4 Replacement Project”.

Questions via phone call may be made to Elissa Overton at (707) 823-2151.

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RFP – Well 4 Replacement Project Page 5 of 6
Prior to submitting proposals, consultants should not contact any other City personnel, elected or appointed officials. The City reserves the right to reject any proposal for violation of this provision.

XI) EVALUATION CRITERIA
The City’s consultant evaluation and selection process is based upon “Qualifications Based Selection” (QBS) for professional services. The following criteria will be used in evaluating the proposals:
a. Responsiveness to solicitation and understanding of project. b. Proposal documentation of demonstrated relevant experience, particularly withwell development and construction of municipal wells for public agencies. c. General qualifications and experience of the firm, project manager, lead design engineer, and other key individuals assigned to projects. d. Clarity of proposal.
e. Information obtained from reference checks.

The City may also contact responding firms to clarify information in proposals or to seek and review additional information deemed pertinent to the evaluation process. The evaluation committee shall determine the final Pre-Qualified Consultants “Short-List” in consideration of the best interests of the City. The evaluation committee consists of up to three (3) City staff from one or more of the following departments: Public Works, Planning, City Administration, and Building.

The final recommendation to Council will be made by the City Manager.

After written proposals have been reviewed, online or in-person interviews with prospective firms may be conducted by the City. If scheduled, oral interviews will be in an informal question/answer format for the purpose of clarifying the proposal. The individuals who represent your firm in any scheduled interview must include the person who would be directly responsible for carrying out the contract, including the Construction Manager and the Lead Inspector.

A Notification of Intent to Award will be sent to the consultant selected. Award is contingent upon the successful negotiation of final contract terms contained in the Master Services Agreement or Professional Services Agreement, and subject to approval by the City.

Negotiations shall be confidential and not subject to disclosure to competing consulting firms unless an agreement is reached.

XII) STANDARD TERMS AND CONDITIONS
a. This RFP does not commit the City to award a contract or to pay any costs incurred for any services.
b. The City, at its sole discretion, reserves the sole right to determine which consultants are ultimately included in the Pre-Qualified Consultants List. c. All proposals will become the property of the City of Sebastopol. Any proprietary information contained in the proposal should be clearly identified as such. d. The City reserves the right to amend this RFQ/RFP from time to time. The current version will be posted on the City website link: bit.ly/SebEng23 e. The cost for developing the proposal is the sole responsibility of the proposer. All proposals submitted become the property of the City.

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RFP – Well 4 Replacement Project Page 6 of 6
f. Prior to award, the apparent successful firm(s) may be required to enter into discussions with the City to resolve any contractual differences. If no resolution is reached, the proposal may be rejected.
g. Proposals are subject to the California Public Records Act. The City cannot protect proprietary data submitted in proposals.
h. Insurance Requirements: Successful proposers, who are invited to be included on the Shortlisted Pre-Qualified Consultants List must furnish the City with the Certificates of Insurance proving coverage as specified in Appendix A. No exceptions will be made to this requirement.

It is the proposer’s responsibility to review these requirements carefully prior to submitting a proposal in response to this solicitation. Your response must indicate your familiarity with the insurance requirements and your willingness to comply with them as they are written. If you take any exceptions to the terms of the contract, these must be included in your proposal in writing. The City will consider this in determining responsiveness to the Request for Proposals.

APPENDICES:

A. Insurance Requirements
B. Professional Services Agreement
C. GHD Report, November 2012
D. Hazen & Sawyer Technical Memorandum, June 2025
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Insurance Requirements Page 1 of 2

APPENDIX A
City of Sebastopol
Insurance Requirements for Consultants
Consultant shall procure and maintain for the duration of the contract insurance against claims for injuries to persons or damages to property which may arise from or in connection with the performance of the work hereunder by the Consultant, its agents, representatives, or employees.

MINIMUM SCOPE AND LIMIT OF INSURANCE
Coverage shall be at least as broad as:

1. Commercial General Liability (CGL): Insurance Services Office Form CG 00 01 covering CGL on an “occurrence” basis, including products and completed operations, property damage, bodily injury, and personal & advertising injury with limits no less than $2,000,000 per occurrence. Ifa general aggregate limit applies, either the general aggregate limit shall apply separately to this project/location (ISO CG 25 03 or 25 04) or the general aggregate limit shall be twice the required occurrence limit.

2. Automobile Liability: Insurance Services Office Form Number CA 0001 covering, Code 1 (any auto), or if Consultant has no owned autos, Code 8 (hired) and 9 (non-owned), with limit no less than $1,000,000 per accident for bodily injury and property damage.

4. Professional Liability (Errors and Omissions) Insurance appropriates to the Consultant’s profession, with limit no less than $2,000,000 per occurrence or claim, $2,000,000 aggregate.

The Retroactive Date must be shown and must be before the date of the contract or the beginning of contract work. Insurance must be maintained and evidence of insurance must be provided for at least five (5) years after completion of the contract of work. If coverage is canceled or nonrenewed, and not replaced with another claims-made policy form with a Retroactive Date prior to the contract effective date, the Consultant must purchase “extended reporting” coverage for a minimum of five (5) years after completion of contract work. A copy of the claims reporting requirements must be submitted to the City of Sebastopol for review.

Other Insurance Provisions
The insurance policies are to contain, or be endorsed to contain, the following provisions:

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Insurance Requirements Page 2 of 2
Primary Coverage
For any claims related to this contract, the Consultant’s insurance coverage shall be primary insurance coverage at least as broad as ISO CG 20 01 04 13 as respects the City of Sebastopol, its officers, officials, employees, and volunteers. Any insurance or self-insurance maintained by the City of Sebastopol, its officers, officials, employees, or volunteers shall be excess of the Consultant’s insurance and shall not contribute with it.

Notice of Cancellation
Consultant shall provide immediate written notice if (1) any of the required insurance policies is terminated; (2) the limits of any of the required policies are reduced; (3) or the deductible or self-insured retention is increased. In the event of any cancellation or reduction in coverage or limits of any insurance, Consultant shall forthwith obtain and submit proof of substitute insurance.

Waiver of Subrogation
Consultant hereby grants to the City of Sebastopol a waiver of any right to subrogation which any insurer of said Consultant may acquire against the City of Sebastopol by virtue of the payment of any loss under such insurance. Consultant agrees to obtain any endorsement that may be necessary to affect this waiver of subrogation, but this provision applies regardless of whether or not the City of Sebastopol has received a waiver of subrogation endorsement from the insurer. However, the Workers’ Compensation policy shall be endorsed with a waiver of subrogation in favor of the City of Sebastopol for all work performed by the Contractor, its employees, agents, and subcontractors.

Acceptability of Insurers
Insurance is to be placed with insurers authorized to conduct business in the state with a current A.M.

Best’s rating of no less than A:VII, unless otherwise acceptable to the City of Sebastopol.

Verification of Coverage
Consultant shall furnish the City of Sebastopol with original Certificates of Insurance including all required amendatory endorsements (or copies of the applicable policy language effecting coverage required by this clause) and a copy of the Declarations and Endorsement Page of the CGL policy listing all policy endorsements to the City of Sebastopol before work begins. However, failure to obtain the required documents prior to the work beginning shall not waive the Consultant’s obligation to provide them. The City of Sebastopol reserves the right to require complete, certified copies of all required insurance policies, including endorsements required by these specifications, at any time.

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City of Sebastopol Agreement for Professional Services Page 1 of 10

RECITALS:

A. City desires to employ Consultant to furnish professional services in connection with the project described as Professional Audit Services.

B. Consultant has represented that Consultant has the necessary expertise, experience, and qualifications to perform the required duties.

NOW, THEREFORE, in consideration of the mutual premises, covenants, and conditions herein contained, the parties agree as follows:

SECTION 1 – BASIC SERVICES
Consultant agrees to perform the services set forth in Exhibit A, “Scope of Services” and made part of this Agreement.

SECTION 2 – ADDITIONAL SERVICES
Consultant shall not be compensated for any services rendered in connection with its performance of this Agreement which are in addition to or outside of those set forth in this Agreement or Exhibit A, “Scope of Services”, unless such additional services and compensation are authorized in advance and in writing by the City Council or City Manager of the City.

SECTION 3 – TIME FOR COMPLETION
The time for completion of services shall be as identified in Exhibit A, “Scope of Services”.

SECTION 4 – COMPENSATION AND METHOD OF PAYMENT
A. Subject to any limitations set forth in this Agreement, City agrees to pay consultant the amount specified in Exhibit A, Proposal dated [date], attached hereto and made a part hereof. Total compensation shall not exceed a total of $[amount], unless additional compensation is approved in accordance with Section 2.

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C. Payment to the Consultant for work performed pursuant to this Agreement shall not be deemed to waive any defects in work performed by Consultant.

MINIMUM SCOPE AND LIMIT OF INSURANCE
Coverage shall be at least as broad as:

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City of Sebastopol Agreement for Professional Services Page 3 of 10

Other Insurance Provisions
The insurance policies are to contain, or be endorsed to contain, the following provisions:

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The provisions of this section do not apply to claims to the extent occurring as a result of the City’s sole negligence or willful acts or misconduct.

Consultant expressly waives any claim Consultant may have to any such rights.

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Any future position of City on such projects shall not be considered a conflict of interest for purposes of this section.

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SECTION 15 – COMPLIANCE WITH CIVIL RIGHTS
During the performance of this contract, Consultant agrees as follows:

B. Nondiscrimination Civil Rights Act of l964. Consultant will comply with all federal regulations relative to nondiscrimination to federally-assisted programs.

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City of Sebastopol Agreement for Professional Services Page 8 of 10 basis and made available to City if and when required for a period of up to 3 years from the date of Consultant’s final invoice.

B. Consultant’s records and design calculations will be available for examination and audit if and as required. The cost of any reproductions shall be paid by City.

To City: City Manager
7120 Bodega Ave
Sebastopol, California 95472
To Consultant: [Consultant Name]
[Address]
[City, State, Zip Code]

Notice shall be deemed effective on the date personally delivered or transmitted by facsimile, or, if mailed, three (3) days after deposit in the custody of the U.S. Postal Service.

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City of Sebastopol Agreement for Professional Services Page 10 of 10 10 SECTION 27 – SEVERABILITY
If any term, condition or covenant of this Agreement is declared or determined by any court of competent jurisdiction to be invalid, void or unenforceable, the remaining provisions of this Agreement shall not be affected thereby and the Agreement shall be read and construed without the invalid, void or unenforceable provision(s).

SECTION 28 – SPECIAL PROVISIONS
This Agreement is subject to the following special provisions: none.

IN WITNESS WHEREOF, the parties hereto have accepted, made, and executed this Agreement upon the terms, conditions, and provisions above stated, the day and year first above written.

City: Consultant:
[Company]
By: By:

Name: Mary Gourley Date Name: [Name] Date
Title: Interim City Manager Title: [Title]
Approved as to Form:

By:

Name: Alex Mog Date
Title City Attorney
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Drinking Water Regulatory
Compliance Feasibility Project
City of Sebastopol
Public Works Department
November 2012
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DRINKING WATER REGULATORY

COMPLIANCE FEASIBILITY PROJECT

CITY OF SEBASTOPOL, PUBLIC WORKS DEPARTMENT
Project No. 02061-12001-32003
Prepared for:

City of Sebastopol
Prepared by:

Aaron Sullivan, PE
Project Engineer
Reviewed by:

Elizabeth Cargay, PG
Senior Geologist
November 30, 2012
GHD Inc.
2235 Mercury Way Suite 150 Santa Rosa CA 95407 USA
T 1 707 523 1010 F 1 707 527 8679 E [email protected] W www.ghd.com Agenda Item Number 3
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02061-12001-32003 i of ii November 2012
Contents

1. Executive Summary .......................................................................................................................... 1

1.1 Introduction ............................................................................................................................. 1

1.2 Section 2 – Well Site Assessments and Treatment Options .................................................. 1

1.3 Section 3 – Alternatives analysis ............................................................................................ 2

1.4 Section 4 – Implementation Plan ............................................................................................ 2

2. Well Site Assessments and Treatment Options ............................................................................... 4

2.1 Introduction .............................................................................................................................. 4

2.1.1 Purpose ............................................................................................................................. 4

2.2 Background.............................................................................................................................. 4

2.2.1 System Overview and Historical Water Quality ................................................................ 4

2.3 Hydrogeologic Conditions ........................................................................................................ 6

2.4 Well Site Assessments ............................................................................................................ 7

2.4.1 Well 4 ................................................................................................................................ 7

2.4.2 Well 5 ................................................................................................................................ 9

2.4.3 Well 6 .............................................................................................................................. 11

2.4.4 Well 7 .............................................................................................................................. 13

2.4.5 Well 8 .............................................................................................................................. 14

2.5 Treatment Options and Technologies ................................................................................... 15

2.5.1 Treatment for Arsenic Removal ...................................................................................... 15

2.5.2 VOC Removal ................................................................................................................. 17

2.5.3 Import Water ................................................................................................................... 17

2.6 New Well Source ................................................................................................................... 17

3. Alternatives Analysis ....................................................................................................................... 18

3.1 Introduction ............................................................................................................................ 18

3.1.1 Purpose ........................................................................................................................... 18

3.1.2 Development of Alternatives ........................................................................................... 18

3.2 Treatment and Supply Alternatives Analysis ......................................................................... 18

3.2.1 Independent Zone Analysis............................................................................................. 18

3.2.2 System-Wide Analysis .................................................................................................... 25

3.3 Alternatives Analysis .............................................................................................................. 28

3.4 Alternatives Analysis Recommendations .............................................................................. 30

3.5 Alternatives Analysis Conclusion ........................................................................................... 31

4. Implementation Plan ....................................................................................................................... 32 Figure:

Figure 1 – Well Location Map
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02061-12001-32003 ii of ii November 2012
Contents (continued)
Tables:

Table 1 – Historical Summary of Supply Well Analytical Data Table 2 – Water Supply Well Construction Data
Table 3 – Water Supply Well Yield, Water Quality Issues and Treatment Appendices:

Appendix A – Various Figures from PES’s Water Supply Assessment Report, Northeast Area Specific Plan, June 27, 2007
Appendix B – Various Figures from ECM Group’s Remedial Action Plan for 501 S. Main Street, May 7, 2012
Appendix C – Various Figures from CSS Environmental Feasibility Study and Comprehensive Remedial Action Plan, April 24, 2009
Appendix D – Arsenic Speciation Laboratory Report and BESST Zone Test Report Appendix E – Various Figures from Streamborn’s Installation of Groundwater Monitoring Wells and Groundwater Monitoring, December 19, 2005
Appendix F – Copy of Letter from City of Sebastopol PWD to Sonoma County Water Agency Appendix G – Alternative Net Present Value Calculation
Appendix H – Reconnaissance Level Estimates of Probable Cost Agenda Item Number 3
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02061-12001-32003 1 of 33 November 2012

1. EXECUTIVE SUMMARY

1.1 INTRODUCTION
The City retained the services of GHD to conduct a Drinking Water Regulatory Compliance Feasibility Study with the goal of assessing various feasible groundwater system treatment options available to the City in order to:

1. Achieve and maintain long-term compliance with existing and new regulatory requirements, primarily for arsenic and tetrachloroethylene (PCE) in municipal drinking water;

2. Maintain flexibility and redundancy of water supply sources in order to assure long-term production capacity to serve customers; and

3. Assess the opportunities, constraints, and costs of various strategies.

GHD completed this Feasibility Study in three separate task elements with the goal of identifying the best treatment options for the City’s drinking water system as a whole. The Study analyzed various combinations and overall costs of treatment to keep the City in compliance with water quality standards of the State. The three Feasibility Study tasks were to:

1. Summarize historical well data, complete well site assessments and identify treatment options (Section 2);

2. Complete an Alternatives Analysis with various options and compare costs (Section 3); and

3. Summarize and Prepare an Implementation Plan (Section 4).

Once each task was completed, a Technical Memorandum was prepared. Upon City approval, the Technical Memorandum was converted into a Chapter of this Final Report. A summary of each of the three tasks is presented below with the final recommendations at the end.

1.2 SECTION 2 – WELL SITE ASSESSMENTS AND TREATMENT OPTIONS Section 2 contains the well assessments and treatment options. The well assessment portion gives an understanding of the design, operation, and contaminants (if applicable) impacting each of the City’s five wells.

The City of Sebastopol’s (City) municipal groundwater system is supplied by five wells feeding two pressure zones, but only three wells (Wells 4, 6 and 8) are currently active. Wells 4, and if activated, 5 and 7, supply Pressure Zone 1. Wells 6 and 8 supply Pressure Zone 2.

Wells 4 and 5 have been impacted by chlorinated hydrocarbons but are currently below the maximum contaminant levels (MCL). Naturally occurring arsenic is prevalent in Wells 6 and 7 above the MCL. Well 4 is currently fitted with a granular activated carbon (GAC) treatment system and Well 6 uses blending of Zone 1 water to lower arsenic concentrations. Well 7 is currently not in production due to slightly elevated, but stable, arsenic concentrations above the MCL.

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02061-12001-32003 2 of 33 November 2012
A discussion of the treatment options is given to identify various treatment technologies and operational changes that are available to limit, reduce, or remove the contaminant(s) present in the well water. For the initial identification of treatment options in this section, all available known options were identified regardless of their cost or feasibility for implementation at the City’s well sites. Treatment options included reviewing blending, adsorptive media (e.g. granular ferric hydroxide (GFH)), oxidation, coagulant-assisted coprecipitation/ filtration, lime softening, high pressure membranes, ion exchange, electrodialysis reversal, and advanced oxidation (ozone/UV) with hydrogen peroxide. Well options included new well sources to replace wells and/or enhancing the existing well.

1.3 SECTION 3 – ALTERNATIVES ANALYSIS
Section 3 contains information on the treatment alternatives to examine the various options available at each of the well sites to select a preferred alternative for each well with the most cost-effective treatment for meeting State and Federal drinking water standards. The preferred alternative includes elements that would result in a robust City water supply system that is operationally flexible with sufficient redundancy to provide long term solutions with the lowest overall life cycle cost.

The various options and alternatives were developed based on meeting three criteria: operational flexibility, operational redundancy, and life cycle cost. In developing the various alternatives, the two individual pressure zones (Zone 1 and Zone 2) were first analyzed independently from one another; then the entire system was analyzed as a whole (Zone 1 and Zone 2 combined) to develop the list of alternatives for consideration and final selection.

The recommended best alternative is Alternative Z2D-2 which includes:

1. Well 4 GAC media changeout, when required;1

2. Well 7 modifications possibly including:, lowering of pump, and reducing pump output and then if necessary, double packer or add swages to well casing;

3. Well 6 Iron coprecipitation treatment system installation, assuming Well 7 modifications are successful; and

4. Well 7 blending after a partial treatment with GFH adsorptive media.

1.4 SECTION 4 – IMPLEMENTATION PLAN
The Implementation Plan is described in Section 4 and details the recommended sequence of steps to implement the recommended alternative. Greater detail of the steps and a flow chart are presented in Section 4. In summary, the Implementation Plan is as follows:

1. Implement modifications to Well 7 including lowering the pump and flow output and monitor arsenic levels.

1 Here and elsewhere in the report, Well 4 GAC media changeout is included for discussion as part of overall strategy; however, this eventual need is known and partial funds remain available for this purpose as a result of the well litigation settlement.

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2. If modifications at Well 7 do not result in lowering of the arsenic concentrations to below the MCL, consider sealing off additional sections of the well screen with sweges or multiple packers.

3. Following improvements at Well 7, improvements to Well 6 are recommended, specifically in the installation of an iron co-precipitation treatment system. GFH treatment is also acceptable at Well 6 as an alternative. The suitability of GFH as a treatment technology is dependent on the expected frequency of the media change out. To determine the expected frequency of the media change out, complete testing of the water accompanied by a pilot study is recommended regardless of the selected technology. Prior to implementation of any technology at full-scale, pilot testing of the chosen technology is strongly recommended to validate the process, develop design criteria, accurate life-cycle costs and operational familiarity with the process.

4. Even if immediate modifications at Well 7 are successful, it is still recommended that the partial treatment system employing GFH or similar adsorptive media be designed and installed because the arsenic-impacted groundwater may still bypass the packer through the sand pack over time and raise the arsenic level again. If the immediate modifications do not work, then partial treatment employing GFH should be considered prior to Well 6 treatment.

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2. WELL SITE ASSESSMENTS AND TREATMENT OPTIONS

2.1 INTRODUCTION
Information presented in this section is taken from Technical Memorandum 1 originally submitted to the City on August 1.

2.1.1 PURPOSE
Through meetings with Sebastopol Department of Public Works (DPW) staff, well design and performance data review, well water quality data collection and review, and a site visit conducted on June 14, 2012, GHD performed an assessment of the City wells to determine well condition, pumping performance, and water quality. This information was then used to develop treatment options related to the wells and their particular performance and water quality issues.

2.2 BACKGROUND

2.2.1 SYSTEM OVERVIEW AND HISTORICAL WATER QUALITY
The City’s municipal water system is supplied by five wells feeding two pressure zones (Figure 1). Three wells are currently active and two wells are inactive. Well 5 is inactive due to past contamination from dry cleaning chemicals and Well 7 has recently been placed on inactive status due to arsenic concentrations over the MCL. Well 4 is impacted by chlorinated hydrocarbons and Arsenic is prevalent in Wells 6 and 7.

Wells 4 and 7 supply Zone 1 while Wells 6 and 8 supply Zone 2. Table 1 includes both historic and the most current water quality data for the contaminants of concern and Table 3 includes specific information on each well’s yield, water quality issues, and treatment. In general, the following Table below summarizes the basic information and issues with each well.

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Well Summary
Zone Zone 1 Zone 2
Well No. 4 5 7 6 8
Status Active Inactive since 1987 Active Active Active
Year installed 1953 1960 1996 1968 2007
Current Treatment
Granular Activated
Carbon
(GAC)
none
Packer
installed at
395-400’ to
seal off upper
screens
Blending
Zone 1 water
with Well 6
water to prior to
distribution to
Zone 2
none
Contaminant(s) of
Concern 1,2 DCA PCE
PCE (from dry
cleaner (which
has since
been <5 in
well since
1993)
BTEX and
MTBE nearby
As in the form
of
As(III)
As in the form of
As(V) none
Recent
Contaminant
Level in City Well
(2011-12)
<5 µg/L 0.49 µg/L
(0.29
treated)

0.52 µg/L <0.5 12 µg/L
(Annual Avg) 19-24 µg/L none
MCL 5 µg/L 5 µg/L 5 µg/L
B=1 µg/L
T=150 µg/L
E=300 µg/L
X=1,750 µg/L
MTBE Primary
= 13 µg/L
(Secondary
= 5 µg/L)
10 µg/L 10 µg/L none
Comments
1, 2 DCA currently not
present above detection
limit; PCE has been
detected, up to 0.49
µg/L; and, As (V) is
below MCL.

Prior to putting well back online,
City should consider treatment for
BTEX and MTBE due to nearby
contaminate source.

As (III)
concentrations
were above
the MCL due
to failing
packer and
Arsenic likely
moving
through the
sand pack.

As (V)
concentrations
continue to rise,
reducing the
effectiveness of
blending.

Well 8
replaced
Well 2 at
same site;
Arsenic
was
above
MCL in
old Well 2
Acronyms:

As Arsenic
As (III) Arsenic (III), naturally occurring, at a valance of +3 As (V) Arsenic (V), naturally occurring, at a valence of +5 BTEX benzene, toluene, ethyl benzene, and xylene (petroleum derived volatile organic compounds) MCL maximum contaminant level (drinking water standard) MTBE Methyl tertiary-butyl ether, primary MCL with secondary MCL in parentheses ND non-detect (level)
PCE Perchloroethylene, or aka tetrachloroethylene
µg/L micrograms per liter (or parts per billion, ppb)
1, 2-DCA 1, 2 Dichloroethane
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 Well 4 has been impacted by chlorinated hydrocarbons (1, 2-DCA) and more recently low levels of PCE and a Granular Activated Carbon (GAC) treatment system was installed to effectively address these contaminants.
 Well 5 has been impacted with Volatile Organic Compounds (VOCs) associated with dry cleaning chemicals, e.g., tetrachloroethylene (PCE) and trichloroethylene (TCE), and is in close proximity to a petroleum plume.
 Historically arsenic has been detected at Well 4 ranging between 2-7.9 µg/L and is currently at levels below the MCL of 5 µg/L.
 Wells 6 has arsenic concentrations above the MCL. Well 6 has the highest concentration of arsenic of the Sebastopol well field and is blended with water supplied from Zone 1.  Well 7 has historical arsenic concentrations at the MCL. Recently, Well 7’s current annual average concentration of arsenic is above the MCL.
 Well 8, the newest, active well, is providing water with acceptable quality, and was constructed only in the lower aquifer zone to avoid the arsenic in the upper aquifer zone. Well 2, which has since been decommissioned and abandoned, was located adjacent to the Well 8. It had arsenic concentrations above the MCL because it was screened in the upper and lower aquifer zones.

2.3 HYDROGEOLOGIC CONDITIONS
The City is located in western Sonoma County, California, within the Santa Rosa Valley. The City lies on two different hydrologic basins: the Santa Rosa Valley Groundwater Basin (SR Valley) and the Wilson Grove Formation Highlands (WG Highlands). The eastern portion of the City is located in the midwestern margin of the SR Valley. It is located in a northwest trending, structural depression and the City extends from the plains, into the low hills west of the City and into the Coast Range on the east. The steeper portion of the City is within the WG Highlands and is characterized by gently rolling hills between the Santa Rosa Plain and the Pacific Ocean. The City wells extend to depths of 500 to 700 feet deep into the WG Highlands.

According to California Department of Water Resources, California’s Groundwater Bulletin No. 118, Santa Rosa Valley, Santa Rosa Plain Sub basin, 2004 Update, and the USGS Geologic Map of the 7.5 minute Sebastopol, 2008, groundwater source is identified in three major units:

Alluvial deposits cover most of the Santa Rosa Plain and consist of up to 100 feet thick of poorly sorted coarse sand and gravel interbedded with moderately sorted fine sand, silt and clay. Alluvial deposits have a specific yield of 8 to 17%.

Glen Ellen Formation is the principal aquifer in the basin and is situated below the alluvial deposits. This unit consists of partially cemented stream channels and terrace deposits with lenses of poorly sorted gravel, sand, silt and clay with fossiliferous sandstone that vary widely in thickness and extent, but ranges in thickness from 300 to 2,000 feet thick. Wells in this unit can produce more than 500 gallons per minute (gpm), but the average specific yield is 3 to 7% and is the formation where most domestic and irrigation wells are installed. Water quality is generally very good but it may occasionally exceed the secondary MCLs for iron and manganese.

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Wilson Grove Formation (formerly Merced) is the major aquifer in the basin, with a thickness of 300 feet to more than 1,500 feet. It is predominantly a marine sandstone and pebbly sandstone. It is fine to very fine grained, well sorted, massive to poorly bedded, fossiliferous sand and sandstone. Water quality is generally very good but it may occasionally exceed the secondary MCLs for iron and manganese. Wells yield from 100 to 1,500 gpm with specific yields ranging from 10 to 20%.

Below these units is the Petaluma Formation which includes sandstone and conglomerates with sub-angular to sub-rounded clasts of greywacke and other basement rocks and volcanic material. The Franciscan Complex basement rock is below the Petaluma Formation and is composed of massive, white to greenish gray, brown and orange-weathering sandstone and can include argillite and shale with disrupted bedding.

These units outcrop in the hills of the City. The Sebastopol Fault is a northwest trending strike slip fault that runs to the southeast of Sebastopol. Other lineaments also run parallel to the Sebastopol Fault and extend through the northeastern portion of the City. The City wells are all to the west of these faults, approximately 1,500 feet away.

Geologic Maps of these units are shown in a report prepared for the City in June 2007 by PES Environmental, Inc. (PES), entitled Water Supply Assessment, Northeast Area Specific Plan. Copies of the pertinent figures are included in Appendix A for reference. These include a Basin Map, Geologic Map, and a Geologic Cross Section across the City.

2.4 WELL SITE ASSESSMENTS
This section describes a summary of current and pertinent well data provided by the City for their five City wells. The purpose of presenting this information is to provide additional details of the well sites to better understand and thus determine the best treatment options.

2.4.1 WELL 4

2.4.1.1 Site Conditions
Well 4 site is located at 710 Petaluma Avenue in Sebastopol at the intersection of Gravenstein Highway and Palm Avenue (Figure 1). Located on the site is a well and pump house, two vertical GAC filter vessels including process piping, valving, sand removal equipment, and a filter backwash storage/buffer tank. The GAC system became operational in late 2006. The site is sufficiently large enough to support vehicle parking and equipment removal and maintenance.

2.4.1.2 Well and Pump Construction
The well was drilled in 1953 to a depth of 530 feet, has a 14-inch steel casing, and is screened between 237 and 468 feet. The well pump is a 100 horsepower (HP) vertical turbine pump enclosed within a pump house, and rated for 900 gpm capacity. The construction details are summarized on Table 2.

2.4.1.3 Well Impacts
GHD completed a search of data and documents on the GeoTracker website created by the California State Water Quality Control Board for sites with contamination. The website contains copies of reports from open and closed sites in the last 10 years or so. The following open cases were identified near the Well 4 site.

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1. Valero (former Alliance Station), 720 South Main Street;

2. Sebastopol Shell, 778 South Gravenstein Highway;

3. Exxon, 840 Gravenstein Highway;

4. Old Dry Cleaners/Talmadge Wood, 250 South Main Street; and

5. Frees Development Co. Bldg., 501 South Main Street.

Of these sites, the Valero station has impacted the City’s Well 4 at Spooner Park, some 200 feet east, with 1,2-Dichloroethane (1,2-DCA). According to the Third Quarterly Monitoring Report for Valero prepared in 2011, the site has an open North Coast Water Quality Control Board (NCRWQCB) case that indicates total petroleum hydrocarbons as gasoline (TPH-G), benzene, toluene, ethyl benzene and xylenes (BTEX), as well as 1,2-DCA are all potential contaminants of concern at 80 to 100 feet deep. The underground storage tanks (USTs) were removed from the gas station site in 1986 and three double-walled fuel USTs were then installed in place of them. According to reports available for review on the website, groundwater flows in a northeasterly direction at a gradient of 0.01 to 0.008 ft/ft, but moves towards the City Well 4 in a southerly to southwesterly direction as it gets closer to the City well. The soils encountered in the borings were defined as silty sands to sand with silt in the aquifer zones. In 2006, a soil vapor extraction/air sparge system was installed, but was inadequate for the influent concentrations of gasoline. An additional vapor extraction well was installed and is currently being permitted to be added to the current extraction system. Shallow monitoring wells are installed at the edge of the park, between the City well and the Valero station, but none of the monitoring wells have been impacted. Pertinent figures from CSS Environmental’ s (CSS) Remedial Action Plan are included in Appendix B and depict the comingled plumes.

In recent correspondence to the City from Ms. Jan Goebel at the NCRWQCB, it was confirmed that PCE has also been steadily climbing at low levels in the groundwater at Well 4 that had not existed prior. Ms. Goebel completed a search of other sites and well data in the area and has requested that the site located at 250 South Main Street, known to the NCRWQCB as the Old Dry Cleaners/Talmadge Wood site, where a dry cleaning business once existed. The NCRWQCB has instructed the owners at the site to begin response to interim remedial action to abate the contamination moving into the radius of influence of Well 4. This is the same site that contaminated the City’s Well 5.

At the Frees Site, there is TPH-G and BTEX contamination that has extended beyond the parcel limits approximately 150 feet, but is not fully defined. It appears to be moving in a south-southwesterly direction and contamination has been detected as deep as 80-100 feet. This is in the same path as the other plumes, but appears to originate on the Site. A Groundwater Contour Map and Isoconcentration maps from the Remedial Action Plan prepared by the ECM Group in May 2012 are included in Appendix C for reference.

Currently, they are planning on installing a soil vapor extraction treatment system at the site.

2.4.1.4 Contaminants of Concern
Historically, the contaminant of concern has been 1, 2-DCA, but TPH-G and BTEX are also potential contaminants of concern that are in the nearby Valero station. Recent data is also indicating a rise in concentrations of PCE.

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2.4.1.5 Treatment Discussion
Well 4 is fitted with a GAC treatment system to address groundwater contamination from 1, 2-DCA. Since its installation, levels of contamination have steadily and continually dropped below the MCL. TPH-G and BTEX are still potential contaminants of concern, but have not been detected in the groundwater from City Well 4.

While the water is still processed through the GAC, the water quality at this point sufficiently meets drinking water standards such that filtration of GAC may no longer be necessary for treating the 1,2 DCA. However, with the contaminant levels of nearby plumes and if the concentration of PCE continues to rise, the GAC is necessary as it is an effective method for the removal of PCE and other VOCs. In the most recent samples, PCE levels were detected at 0.41 µg/L in the raw water and 0.24 µg/L in the groundwater collected from the 50% through the first GAC filter port.

2.4.2 WELL 5

2.4.2.1 Site Conditions
Well 5 is located on a small triangular parcel one block east of Gravenstein Highway at 6860 Fannen Avenue, Sebastopol (Figure 1). Immediately north of the site is the Joe Rodota Trail. At the site there is a small pump house and a large, baffled settling tank for the removal of sand. The site has limited area, for vehicle parking and appears sufficient to facilitate equipment removal and maintenance.

2.4.2.2 Well and Pump Construction
Well 5 was constructed in 1960, and is of the same type and construction as Well 4. The pump is a vertical turbine fitted with a 60 HP motor, and pump control equipment housed in the pump house. The pump has a capacity to pump 900 gpm and is set at 250 feet below the ground, and is screened between 138 and 528 feet.

2.4.2.3 Well Impacts
In 1987, PCE was discovered in Well 5. After several investigations, it was determined that the PCE originated from the Em’s Chevron/Old Dry Cleaners/Talmadge Wood Site area located to the northwest of Well 5. In 1987, Well #5 was taken out of service. According to an April 2009 report, Feasibility Study and Comprehensive Remedial Action Plan for 250-280 South Main Street, Sebastopol, CA, completed by CSS, “since cessation of pumping at City Well 5, the natural groundwater flow from the Site has consistently been to the south-southeast instead of towards southeast”, towards Well 5. A description of the geology of the area was described in the same report and is summarized below:
“CSS installed a deep monitoring well, designated as MW-17. Logs of well MW-17, to a depth of 120 feet bgs, show that the saturated water table zone soils consist of permeable granular materials including coarse and fine-grained sands and gravels. This alluvial pattern is consistent with the 1960 test hole for City Well 5, located ¼ mile southeast of the site on Fannen Avenue. Logs of City Well 5 indicate that alluvial sands and gravels predominate to a depth of 112 feet where hard sandstone is reported. This sandstone is a potential confining layer at the base of the shallow unconfined water table. The sandstones are marine deposits and are described alternately as hard and soft, some with marine shells present. They predominate the test hole's log from 112 feet to a depth of almost 300 feet. Clay with various amounts of sand and or gravel appears from about 300 to a depth of about Agenda Item Number 3
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340 feet. Sands and sandstones predominate to the total depth of the test hole at 646 feet with yellow and blue clay with sand noted between 560 and 590 feet. City Well 5 is screened from 138 to 528 feet, with an annular seal of 120 feet. Another municipal well in the site vicinity, City Well 4, located approximately 1,200 feet downgradient, is screened from 237 feet to 468 feet with an annular seal of 135 feet. Sandstone was encountered in this well at a depth interval of about 135 to 270 feet with underlying clay to about 370 feet.”
Since then, the PCE has decreased to the point that the City has been considering options to reactivate the well. In order to assess this possibility, GHD reviewed GeoTracker for nearby sites that could potentially impact this well. The following sites were reviewed:

1. Em's Chevron, 280 Main Street;

2. Old Dry Cleaner/Talmadge Wood; 250 Main Street, South;

3. Angelo Giusti Class III Disposal Site, East of Highway 12, between Burnett and Bodega Ave;

4. J&W Foreign Auto Repair, 401 Main Street, South;

5. Nelson Site , 327 Petaluma Avenue; and

6. Wyatt's Tire Service, 100 Brown Street.

At the Chevron and Old Dry Cleaner sites, a combined workplan has been approved by the NCRWQCB in March 2012. This workplan is for additional drilling to be completed in an attempt to gain information regarding the vertical distribution of groundwater contaminants in the subsurface and assess their diffusion from varying strata within the shallow water-bearing zone. However, it was noted in May 2012 by Analytical Sciences, that PCE was now being detected consistently in Well 4, at 0.49 µg/L in 2012. The Old Dry Cleaner site’s monitoring well MW-14 is a shallow screened well [from 25 to 40 feet below ground surface (bgs)] and is located between the site aLabnd Well 4. MTBE was detected in this monitoring well in August and December of 2011, and in December 2011 it had detectable levels of PCE.

In-situ chemical oxidation has been identified as a remedy for cleanup of the groundwater for VOCs on and near the site. Further downgradient of the Site, VOCs are comingled with petroleum hydrocarbon releases from the J&W Foreign Auto Repair site located at 401 South Main Street, South. Different treatment processes (permanganate and persulfate injections) have been identified to further cleanup the comingled VOCs and petroleum hydrocarbons. This treatment would involve injecting approximately 9,000 gallons of a 2% Permanganate (MnO4) solution at the Site and approximately 8,000 gallons of a 2% persulfate (S2O8) solution near J&W Foreign Auto Repair.

The NCRWQCB has requested that the sites define the extent of MTBE in the groundwater and provide a workplan from these comingled plume owners. To date, a workplan for extent definition has not been implemented.

At the Giusti Disposal site, GeoTracker indicates that there is a solvent investigation going on in 1987, but no other information is given. Additional information is needed to assess the implications on the City wells.

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The Nelson site appears to have had a gasoline leak, but no enforcement has been placed on this site.

There was no additional information on this site on GeoTracker. Additional information is required to assess the impacts on the City wells.

At the Wyatt’s Tire Service site, TPH-G, BTEX, and MTBE are all contaminants of concern due to fuel tank leaks in the 1990s. The solvent 1, 2-DCA has also been detected in the groundwater at varying levels. Most of the known contamination appears to exist in the very shallow groundwater zones, above a locally observed, shallow, clay aquitard and appears to be increasing in concentration in the monitoring wells.

Shallow wells are 10 to 10.5 feet deep and groundwater flow has varied considerably, but has tended to move in a southerly to a southeastern direction. An interim soil vapor extraction system was installed in 2011 and ran for a brief time and a Site Conceptual Model and Corrective Action Plan are currently being prepared.

2.4.2.4 Contaminants of Concern
Well 5 has been out of service since 1987 due to PCE contamination in concentrations exceeding MCL standards resulting from the Old Dry Cleaners site upgradient of the site. However, there are several potential sources of contamination that could affect Well 5 as indicated above. VOCs: TPH-G, BTEX, MTBE and 1, 2 DCA are all potential sources of contamination. Currently, the City Well 5 is inactive but the City has continued monitoring the contamination. As present time PCE concentrations are below the MCL, at 0.5 µg/L, and the City would like to consider placing the well back into active status. The treatment for this well should consider all the VOCs and MTBE as potential contaminants of concern.

2.4.2.5 Treatment Discussion
No treatment currently exists at the well site. While the PCE concentrations are currently below the MCL, it is likely that contaminant concentrations will increase when actively pumping on the aquifer and may bring in the other VOCs listed above. For the purposes of this study, it should be assumed that the concentration has the potential to increase and should therefore be treated prior to entering the distribution system. Similar to Well 4, the process by which PCE and the other VOCs are typically and effectively removed is adsorption employing GAC.

2.4.3 WELL 6

2.4.3.1 Site Conditions
Well 6 is located at 991 Gravenstein Highway near Hazel Cotter Court to the south and Redwood Avenue to the north (Figure 1). This well replaced Well 1 and 3. The large, triangular property contains a pump house, well, booster/blending pumps, a cyclone type sand separator, and electrical gear. A significant portion of the site is unpaved and unimproved.

2.4.3.2 Well and Pump Construction
The well was installed in 1968 to 572 feet deep and screened between 172 to 552 feet. The well has a 125 HP submersible pump and has a capacity to pump 750 gpm. The City has just finished installing a booster pump/blending station that blends groundwater from Well 6 with water from one of the City reservoir tanks (Zone 1) at an approximate ratio of 1:3 to reduce Arsenic that appears to be naturally occurring.

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2.4.3.3 Well Impacts
Arsenic has been steadily increasing in this well. In a Spinner Test completed in December 2004, depth discrete sampling indicated that the Arsenic appears to be elevated in the shallower aquifer zones (above the MCL of 10 µg/L) in the upper approximate 350 feet (Upper Aquifer), with Arsenic below the MCL below in the lower aquifer zones (Table 1) (Lower Aquifer). In 2008, the City installed an inflatable packer to attempt to isolate the shallow elevated Arsenic zones, but it did not work as intended.

At least one recent test from 2008/2009 for Title 22 constituents detected elevated Aluminum and Manganese above the Secondary MCL; however, subsequent tests reported concentrations well below the Secondary MCL and therefore do not appear at this time to be contaminants of concern.

A review of the GeoTracker website was completed for the area surrounding Well 6. No open cases were indicated near the Well 6, but it is approximately 2,000 feet south of Well 4, which is impacted with VOCs.

Although downgradient, it is not expected that the comingled plumes affecting Well 4 would reach Well 6.

2.4.3.4 Contaminants of Concern
Groundwater collected from Well 6 contains elevated, naturally occurring Arsenic above the MCL. Arsenic has been detected below 50 µg/L in the groundwater around the Santa Rosa Basin and has been linked to naturally occurring Arsenic of the Glen Ellen Formation. According to a USGS study for the neighboring Sonoma Valley Groundwater Basin completed in 2006 (Scientific Investigation Report 2006-5092), thermal water and upwelling fault-zone water contain higher concentrations of dissolved elements because mineral solubility generally increase with temperature. The temperature in the City wells does not appear to be disproportionately higher than the temperature in other City wells. Manganese and iron have also been noted to be detected in other cities in the Santa Rosa Plain associated with naturally occurring solubles, but do not appear to be occurring in Sebastopol.

With Arsenic being the contaminant of concern, further analysis of Arsenic (As) to determine the valance was conducted on July 30, 2012 by the City. A sample was collected in specially prepared containers prepared by the testing laboratory. Results indicate that the groundwater collected from Well 6 contains mostly pentavalent arsenic (As [V]) valance water (Appendix D). Arsenic in this valance state is more readily removable than trivalent arsenic (As [III]), which would require oxidation pretreatment to convert to As [V] before effective treatment by many of the most commonly used methods. Additional information on the treatment options and technologies are presented later in the memorandum.

2.4.3.5 Treatment Discussion
Well 6 has recently been fitted with a booster pump/blending station which blends water supplied from Zone 1 with water supplied from Well 6 before supplying the blended water to Zone 2. This method has been successful in lowering the concentration of Arsenic, but current blended water quality remains close to the 10 µg/L concentration for Arsenic. Should levels continue to rise, the blending of Zone 1 water with Well 6 water will become less effective for the same production volume. Well 6 would then require a reduction in production volume prior to blending or will require a treatment step at the well head to maintain concentrations at or below the MCL.

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2.4.4 WELL 7

2.4.4.1 Site Conditions
Well 7 is located at 1157 Village Way, Sebastopol, on a small parcel located on the corner of Cooper Road and Village Way (Figure 1). The site is completely built upon and contains a pump house.

2.4.4.2 Well and Pump Construction
The well was installed in 1996 with multiple screen intervals between 270 and 670 feet deep. The well pump is a 100 HP submersible pump, set at 420 feet deep with a capacity of 800 gpm. An inflatable packer is installed at 395-400 feet.

2.4.4.3 Well Impacts
Arsenic has been detected above the MCL in this well since 2004. In a Spinner Test completed in November 2006, depth discrete sampling indicated that the Arsenic appears to be elevated in the shallower zones (above the MCL of 10 µg/L) in the upper approximate 350 feet, with Arsenic below the MCL in the lower zones (Table 1). In 2008, the City installed an inflatable packer to isolate the shallow elevated Arsenic zones.

The packer was then moved to 395 feet and inflated. The level of arsenic was below the MCL for several years, but slowly increased until the level was above the MCL.

In October 2012, the City determined the packer pressure was too low and the packer was likely leaking.

They fully inflated the packer and the arsenic level dropped but was still above the MCL. The City had to take the well off-line.

In November 2012, a dye test was completed by BESST Inc, where dye was placed in the well at several depths just above the inflated packer, and tests completed to assess if the dye was passing through. The dye was not detected below the packer, but BESST verbally indicated that the dye could stick to the gravel.

They also verified that when dye was injected below the packer, it was detected. This test, although verifying that the packer was effectively sealing off the upper aquifer within the well casing, it was inconclusive at determining how quickly the groundwater is passing from the upper aquifer to the lower aquifer through the gravel pack.

A review of the GeoTracker website was completed for the area surrounding Well 7. One open case was indicated to the west and up/crossgradient of Well 7 and one active gas station was noted nearby.

1. Private Residence, 7156/7176/7160 Witter Road, Sebastopol, Cleanup Status: Open - Site Assessment, RB Case # : 1NSO732; and

2. Ultramar Station, 1080 South Gravenstein Highway, Sebastopol, No open case at current gas station.

In 2008, the NCRWQCB compiled data from many domestic wells located near Witter Road and Elphick Road, named the Witter/Elphick Study Area due to a detection of VOCs in a private well nearby. In 2002, NCRWQCB staff sampled over 65 domestic wells and identified VOCs above the MCLs in 19 wells; specifically, PCE and carbon tetrachloride. In 2005, an investigation determined that groundwater was moving in a north-northeast direction and that VOCs and Nitrate/Nitrite were detected above the MCLs in the groundwater at this site. Since then, the NCRWQCB has determined that a former machine shop once Agenda Item Number 3
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existed on the 7176/7160 property and had a dry well that may be associated with the contaminants.

Pertinent figures are attached as Appendix E, which show the location of the private wells and the contamination in relation to the City well. A workplan has been requested to investigate the plume, but has not been completed as of the review in GeoTracker. Additional information is needed to assess the potential future implications on the Well 7, but to date, no VOC contamination has been detected in this well.

Well 7 is approximately 3,000 feet south of Well 4, which is impacted with VOCs. Although likely downgradient, it is not expected that the comingled plumes affecting Well 4 would affect Well 7.

2.4.4.4 Contaminants of Concern
The latest Well 7 water quality test data in 2012 indicates Arsenic concentrations are around the MCL (10 µg/L). Any subsequent increase in Arsenic concentration will place the water from the well above the MCL.

Furthermore, historical water quality data shows several reported concentrations well above 10 µg/L with subsequent tests taken showing concentrations below the MCL. This would appear to indicate that potentially as the well “rests”, concentrations of Arsenic increase in the groundwater at the well. Then, when pumping commences, the Arsenic concentration diminishes over time until a steady state concentration is reached. It is important to note that the Arsenic concentration increases over time when pumping occurs after the resting period. With the current concentration at the MCL, it is likely that future of Well 7 water will be at or above the MCL.

2.4.4.5 Treatment Discussion
No treatment currently exists at Well 7. Due to the small size of the well site, coupled with the fact that the well site, and the surrounding parcels have effectively been built out, treatment options are limited at this site.

Options include blending using water from Zone 2 and partial treatment of the water using adsorption media to lower arsenic concentrations. Additional discussion is in the Treatment Options section below.

2.4.5 WELL 8

2.4.5.1 Site Conditions
Well 8 is located at 351 Jewell Avenue at the corner of Jewell and Calder Avenues, on the same site as the former Well 2 (Figure 1). The decommissioned Well 2 resided inside the pump house. Well 8 is outside the pump house located in a precast concrete structure located 50 feet from the former Well 2. Also located in the pump house, is a booster pump station similar to Well 6, but it is not used for blending. Its sole purpose is to facilitate inter-zone water transfers.

2.4.5.2 Well and Pump Construction
Installed in 2007, Well 8 is the most recently constructed municipal well in the City. It is a 125 HP submersible pump. Well 8 is screened between 320 and 560 to avoid the naturally occurring Arsenic observed in the shallower zones (<350 feet) seen in other wells.

2.4.5.3 Well Impacts
A GeoTracker review was completed for the area surrounding Well 8. There are no sites with contamination that affect the Well 8 site, but it is approximately 1,500 to 2,000 feet away from Main Street where the Agenda Item Number 3
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comingled VOC/TPH-G/MTBE plume is being investigated near Well 4. It appears that Well 8 is upgradient and has not pulled these contaminants into its radius of influence.

2.4.5.4 Contaminants of Concern
Review of water quality data indicates that there are currently no constituents measured at concentrations that would be the cause of concern. It should be noted that the decommissioned Well 2 did indicate elevated Arsenic concentrations in shallower screened zones (<350 feet) while in operation, but not in the deeper zones.

2.4.5.5 Treatment Discussion
With no contaminants of concern indicated in Well 8, water treatment is not required. Should Arsenic become a constituent of concern, there is sufficient land at the site to support a treatment system and the well house does contain booster pumps that could be used as a blending station.

2.5 TREATMENT OPTIONS AND TECHNOLOGIES
There is a myriad of treatment options, technologies, and scenarios that could be applied the City’s wells.

The treatment options that could be implemented at the City’s municipal wells depend on several factors, specifically:

1. The contaminant or contaminants needing removal;

2. The volume of water requiring treatment, both in terms of the pump’s instantaneous production capability as well as the well’s total volumetric production;

3. Site and space constraints of the particular well site as well as conveyance systems;

4. The relative cost and effectiveness of the treatment equipment relative to other treatment options; and

5. The cost and ease of operation and maintenance and the final selection(s) of treatment options at the other wells.

For the purposes of this section, GHD will evaluate all options including non-existing well specific options such as importing water from the Sonoma County Water Agency (SCWA) aqueduct intertie, installation of a new source well, compared to taking no action at all. Since this is also a study of options, all options shall be listed regardless of their feasibility. In the Section 3, Alternatives Analysis, GHD will review all of the options discussed below to determine the right mix of alternatives to meet the long-range water quality goals of the City of Sebastopol.

2.5.1 TREATMENT FOR ARSENIC REMOVAL
Wells 6 and 7 contain Arsenic levels at or above the MCL and must therefore be addressed. The following Table identifies the leading Arsenic removal technologies for Wells 6 and 7, their relative cost to one another, and the well to which they could be applied. Life cycle costs refer to the cost to purchase, install, operate, and maintain the equipment over the functional life of the equipment. The relative ranking is from 1 to 5, with 1 being the best. Additional discussion on life cycle costs will be included in the Section 3.

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Treatment
Process
Applicable
to Well
Ranked Cost to
Install and Operate Comments
Blending 7 1 Reduced effectiveness at Well 6.

Applicable to 7, especially when
considering space constraints.

Adsorptive Media
(e.g. granular ferric
hydroxide)
6, 7 3 Moderate life cycle cost. Requires regular
replacement of media once exhausted.

Good candidate for Well 6 based on water
production and site conditions
Oxidation 6, 7 2 Moderate life cycle cost, low operating cost. Particularly useful if other
contaminants are present requiring
oxidation (Fe, Mn, etc.)
Coagulant-assisted
Filtration/
Coprecipitation
6, 7 2 Moderate to low life cycle cost. Particularly
effective if As is in As[V] form. If As is in
As[III] form, pre-oxidation will be
necessary. Disposal of backwash
concentrate presents possible issues.

Lime
Softening/Enhanced
Lime Softening
6, 7 2 Moderate capital cost, high operating cost
and chemical cost. Unless hardness is an
issue with raw ground water other
technologies are better suited.

High Pressure
Membranes
6, 7 5 High life cycle cost. Depending on other
water constituents, fouling of membrane
possible.

Ion Exchange 6, 7 4 Moderate to High life cycle cost, selection of resin critical, brine disposal could
present likely industrial discharger
designation.

Electro dialysis
Reversal
6, 7 5 High life cycle cost, energy and labor
intensive. Disposal of concentrate can be
an issue.

Advanced Oxidation
(ozone/UV) with
hydrogen peroxide)
6, 7 5 High life cycle cost, complex to operate.

More appropriate to use when
contaminants are present that are difficult
to remove (e.g. NDMA)
New Well Source to
replace Wells
6, 7 3 High capital cost to design, permit, drill,
and install. Once installed no guarantee
that contamination won’t present itself.

While Section 3 will vet this further, based upon the available information, site constraints, well size, and production data, Well 6 is a candidate for adsorptive media and coagulant assisted filtration. Well 7 lists these treatment options as well, since those technologies are applicable to the removal of Arsenic. However, due to site constraints, there is insufficient room to locate well head treatment technologies at the well with the possible exception of adsorptive media employed to partially treat the well water to below the MCL. Well 7 will be examined further during alternatives analysis.

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2.5.2 VOC REMOVAL
Wells 4 and 5 are historically impacted by VOCs. Well 4 is currently fitted with a GAC adsorption process unit. Well 5 is currently not fitted with any well head treatment system, but is a candidate based on its history.

The following Table is a summary of treatment options for Wells 4 and 5:

Treatment
Process
Applicable
to Well
Ranked Cost to
Install and Operate
Comments
Blending 4, 5 1 With present, low concentrations blending is a viable option at Well 5. Should Well
not be brought back on line, it should be
monitored to see if concentrations rise to
the point where blending becomes
ineffective.

Air Stripping 4, 5 2 Low to Moderate life cycle cost. Easy to operate, but additional mechanical and
power costs associated with air source.

Requires infrequent but regular cleaning of
packed column media. Possible site noise
and aesthetic issues.

GAC adsorptive
media
4, 5 3 Moderate life cycle cost. Requires media
changeout once exhausted. Aesthetic
concerns at Well 5 site. Already in place at
Well 4.

While all technologies listed above are applicable to Well 4, the well has the GAC technology already successfully installed at this well site and the Table just indicates possible future treatment options for comparison. All the above technologies are applicable to Well 5. The limiting factor at Well 5 is location and site constraints. Section 3 will explore this is greater detail. The initial assessment shows that the site is large enough to support the installation and operation of a well head treatment system of the types named above; but its location, street access to the site, site aesthetics, and possible noise are of concern.

2.5.3 IMPORT WATER
The City currently does not import treated domestic water nor does it have the necessary piping and infrastructure to do so. The City is partially in the Russian River watershed and could be listed as a possible recipient of water from SCWA. The importing of water may be an option available to the City. This option will be examined in greater detail for feasibility and programmatic costs during the alternatives analysis presented in Section 3.

2.6 NEW WELL SOURCE
The comparison of treatment versus installation and permitting a new well source as a replacement well will be identified in the following section to understand the overall costs.

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3. ALTERNATIVES ANALYSIS

3.1 INTRODUCTION
Information presented in this section is taken from Technical Memorandum 2 originally submitted to the city on October 19, 2012.

3.1.1 PURPOSE
The purpose of the Alternatives Analysis is to analyze the various options available at each of the well sites and identify and determine a preferred alternative with the most cost-effective treatment or operational scenario for meeting State and Federal drinking water standards. The preferred alternative will include elements that would result in a robust City water supply system that is operationally flexible with sufficient redundancy to provide long term solutions with the lowest overall life cycle cost.

3.1.2 DEVELOPMENT OF ALTERNATIVES
The various options and alternatives were developed and ranked based on meeting three criteria:
operational flexibility, operational redundancy, and life cycle cost. In developing the various alternatives, the two individual zones (Zone 1 and Zone 2) were first analyzed independently from one another; then the entire system (Zone 1 and Zone 2 combined) was analyzed as a whole to develop the list of alternatives for consideration and final selection.

3.2 TREATMENT AND SUPPLY ALTERNATIVES ANALYSIS
This section describes the alternatives for each zone when evaluating separately, first with Zone 1 then with Zone 2, as separate and independent systems. This section also includes analysis of alternatives with the two zones interacting as parts of a combined, single system. By examining the City’s wells in this manner, various alternatives are evaluated in a systematic manner and a recommendation at each well site is made at the end of the analysis. Also included in this section, is a discussion regarding the possibility of importing water from the Sonoma County Water Agency. The final section will examine planning-level estimates of probable costs for installation and life cycle costs.

3.2.1 INDEPENDENT ZONE ANALYSIS

3.2.1.1 Zone 1 Analysis (Wells 4, 5 and 7)
The following Table on page 4 is a summary of all the options available to Zone 1. The discussion of each of these options follows the Table.

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Zone 1 Options
Well Site Option Comments/Issues/Concerns
Well 4 No Improvements, GAC
adsorption to remain
Well 4 has a GAC system installed to remove VOCs.

GAC media may need changeout in the near future.

Well 5
Air stripping
Applicable treatment process, however equipment noise
undesirable due to proximity to residential housing. Public acceptance a concern.

GAC adsorption media
Applicable treatment process, site modification likely
needed to minimize visual impact of process vessels and equipment. Visual impact concerns for public acceptance.

Connection to Well 4 GAC Unit Requires dedicated pipeline to Well 4 GAC site. Requires modification to controls system.

Install dedicated Well 5 GAC
system at Well 4 site
Permits independent operation of the wells. Wasting
backwash/waste cycle from both units may cause sewer
system surcharging. Not considered further.

Maintain inactive status
No pumping allows nearby plume to remain outside well’s area of influence. Any required remediation of plume by 3rd party may reduce the likelihood of treatment
necessary by City.

Well 7
Additional Packer or Swage
Lower pump intake and
Reduce pump output
Semi-permanent/permanent solution for current arsenic
concentration above MCL. If additional packer or swaging or pump reconfiguration are ineffective, arsenic
concentrations likely to continue rising.

Blending
Blending is only an option if additional water is available.

Option would require bringing Well 5 on line and would
require piping modifications or bringing water into Zone 1 from Zone 2.

Replace with New Well
Addition of well possible but insufficient data to determine if similar issues would not present itself; other options are more cost effective. Technically feasible but may not be practical or publicly acceptable. Consider other more
cost-effective options first.

Partial Treat using GFH
Adsorptive Media
Sufficient space at site to accommodate enough media
cells to partially treat arsenic and re-blend to lower
arsenic concentrations
Any Well No Action Zone 1 would effectively remain a one well zone lacking redundancy or reliability.

3.2.1.2 Well 4
As previously stated in Section 2, Well 4 is fitted with a GAC treatment system to address groundwater contamination from 1,2-DCA. Since its installation, levels of contamination have steadily and continually dropped below the MCL. Solvents are still potential contaminants of concern as well as TPH-G and BTEX are still a concern within nearby plumes but have not been detected in the groundwater at City Well 4. While the water is still processed through the GAC, the water quality sufficiently meets drinking water standards such that adsorption using GAC may no longer be necessary. However, with the recent and continued movement and rise in PCE contaminant levels from a nearby plume, the GAC system remains an excellent precautionary and effective method for the removal of PCE and other VOCs. It is recommended that the City Agenda Item Number 3
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continue to closely monitor concentrations of contaminants prior to GAC treatment and compare to posttreatment. this will help the City determine when the adsorptive media has been exhausted and should be replaced. From discussions with the City, the media has never been replaced since the unit was first installed. After analyzing pre- and post-treatment water quality it could not be determined whether or not the GAC media needs changeout or that it may not be adsorbing effectively when the contaminant concentration levels are low. However, if data indicating breakthrough develops then changeout is recommended. Based on the age of the media it is not an unreasonable assumption that media replacement may be warranted in the next one to three years. City staff is monitoring the water quality and is ready to have the media replaced when needed.

3.2.1.3 Well 5
Well 5 has been out of service since 1996 due to PCE contamination. Furthermore, available data from the North Coast Water Quality Control Board (NCRWQCB) files indicates that there are several potential sources of contamination that could affect Well 5 if it were put into active status, specifically TPH-G, BTEX, MTBE and 1,2 DCA along with the current PCE contaminant that was the initial cause of well deactivation. The sources of contamination have been determined to be from an old dry cleaner that is no longer in operation and from a petroleum hydrocarbon plume from a nearby auto repair facility. From recent conversations with the NCRWQCB, recently acquired data indicates that a plume of contaminants is moving towards Wells 4 and 5. While Well 4 is adequately equipped to handle these contaminants via the GAC system should VOC contaminants enter its area of influence, Well 5 presently is not equipped and would require treatment.

The treatment options at Well 5 are limited due to physical site constraints and aesthetic concerns. The two most cost effective treatment options available to the City are GAC adsorption and air stripping. However, based on the site constraints and proximity to the public, air stripping is not feasible, particularly because of noise associated with the blowers required for treatment. Aesthetic concerns would also need to be addressed related to the visual impacts of air stripping.

GAC adsorption is a viable treatment option and does not have the noise impacts that air stripping does.

However, it would still require site modifications to reduce visual impacts and is therefore recommended only if there are no other feasible options available. Possible approaches to address any site impacts are to either house the GAC system in a structure designed to blend with the surroundings or to place the GAC system pad below street level and erect a vegetative barrier such as a fence with plants to screen the system. A building designed to enclose the system would likely be the most expensive option due to the GAC unit’s size and the need to maintain accessibility for maintenance. However, enclosing the GAC unit may have the greatest chance to be acceptable to the public. Conversely, a site design that reduces the visual impact without fully enclosing the system will be less costly but may prove challenging in obtaining public acceptance.

An alternative to adding GAC units for Well 5 is to utilize the existing GAC unit at Well 4. This alternative would require piping from the Well 5 site to the Well 4 site. A new pipeline between the two sites would be installed or existing abandoned water mains could be utilized with rehabilitation of a portion of the pipeline.

This option would also require modifications to the well controls at both sites since only one well should be permitted to pump to the Well 4 GAC unit at a time.

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An alternative to using the existing Well 4 GAC units for Well 5 treatment as described above is to install additional dedicated GAC units at the Well 4 site specifically for Well 5 water treatment. The additional units would permit independent operation of the wells. However, as discussed with Public Works staff, due to the configuration of the sewer system downstream of the existing Well 4 GAC site, installing a complete second GAC unit for Well 5 has the potential to cause surcharging of the sewer system should both GAC units be required to discharge waste at the same time. Any concern of surcharging can be avoided however, by simply requiring coordination of the backwash operation at the different well sites.

A final option that was evaluated for Well 5 is to keep the well in an inactive status for a few more years while the nearby contaminant plumes are remediated and cleaned. While contaminants in Well 5 water are below their MCL’s, active and repeated pumping at Well 5 may draw in contaminants from the nearby plumes. The NCRWQCB has requested that the responsible parties for the nearby plumes take immediate action for cleanup of the plumes. In discussions with Jan Goebel of the NCRWQCB, if immediate additional remedial action is taken on the responsible party’s part, the plume may be significantly reduced in the next 3-5 years and then there may not be any need to treat the groundwater at Well 5 and the cost could be avoided.

Because the City has other treatment options and additional costs to consider at other well sites, it is recommended that the City delay pumping at Well 5 until the nearby plumes have been sufficiently abated.

3.2.1.4 Well 7
Water from Well 7 is currently impacted with arsenic. Arsenic (As) can be found in two forms in groundwater:

As (III) or As (V), but the MCL is based on Total Arsenic, regardless of valance state. Both contribute to contaminant levels with arsenic (V) easier to treat with coagulation/coprecipitation/filtration technology.

Recent analysis indicates that the valence of arsenic in the groundwater from Well 7 is trivalent, As(III), and is entering the well from the upper portion of the screened interval, the Upper Aquifer. At the time of writing this report, the arsenic annual average level at Well 7 exceeded the MCL and the use of Well 7 has been discontinued until the arsenic concentration is reduced to below the MCL. No treatment system currently exists at Well 7.

Immediate modifications options at Well 7 include, lowering the pump intake and reducing output from the well. Adding packers or swaging one or multiple zones in the upper screen could also be completed.

Swaging represents a longer term, permanent solution compared to the packers and is the process of closing off one or multiple sections of well screen using two half-sections of pipe that are ‘swaged’ and held in place via an interference fit. The two half-pieces of pipe are in 5 foot lengths and are inserted into the well to the appropriate depth. The pieces are then joined to create a ‘whole’ piece of pipe. Similar in function to a packer, the sections are permanently installed to block screened intake sections of the well to isolate those zones of contaminated water without worrying about a packer failing. Theoretically, multiple screens in the zones of the arsenic contamination can be blocked off and, providing that there is no path of bypassing the swaged inlet screens, arsenic is isolated from the pump suction. However, if pumping hard in very permeable materials, i.e. coarse grained sand pack and alluvial deposits, the arsenic laden groundwater can be pulled around the swage or packer, outside of the casing, through the sand pack or the surrounding formation soil, and into the pump inlet below. It is possible that this is what is occurring in Well 7 since the formation soils around the casing are very permeable and the sand pack used in the well is pea gravel. It was noted that over 70% of the groundwater was being pulled from the upper screened intervals before the packer was installed, and no change in pumping flow rate occurred after the packer was installed. At the time of this Agenda Item Number 3
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report writing, the City determined that the inflatable packer was not inflated properly and increased the nitrogen to further inflate it. The City hired BESST Inc. to complete a dye test to determine if the packer was effectively sealing off the upper aquifer. The field dye test was completed in November 2012 and indicated that the packer was effective in isolating the upper zone from the lower zone in the well casing once completely inflated but the arsenic was still above the MCL. The arsenic impacted groundwater is likely going around the packer, through the sand pack. A report prepared by BESST Inc. is included in Appendix D.

The pump intake is currently located just below the packer and may be located too close to the packer and too close to the screen intervals containing arsenic. By lowering the pump and decreasing the pump flow, there may be less of a pull on the water entering upper screens and less of a likelihood of pulling in the arsenic. This option, if implemented, will have a water production impact since over half of the water supplied by the well comes from the aquifer most affected by the arsenic. If the pump were lowered but pumping volume continues to not be reduced accordingly, the arsenic is likely being pulled down into the pump intake by the process mentioned in the preceding paragraph, negating the effects of the pump lowering.

Lowering of the pump intake and reducing pump output are quickly implementable, short-to-midterm solutions that may immediately address the recent exceedance of the MCL for arsenic. By lowering the pump intake to a level either deeper in the screened interval (>100 ft deeper) or to a depth below the screen interval, a decreased volume of water from the arsenic-contaminated aquifer would be pumped. With a higher volume of water from the uncontaminated lower zone with the decreased volume of arsenic impacted water would result in an overall reduction in the arsenic concentration for the total volume of water pumped.

Similarly, pumping less water by reducing pump output will theoretically have a similar effect. However, these two options alone may only present temporary solutions. Without the ability to fully isolate the upper aquifer zone and no other means to dilute the water from Well 7 (i.e. blending) lowering the intake and reducing pump output may only provide interim solutions. While current concentrations of arsenic are holding steady at 12 µg/L, concentrations may change in the future and negate any improvements to water quality achieved with the implementable modifications. City staff has stated that the pump must be started at a high rotation speed to prevent bearing damage. To be able to start the pump at this high speed and then reduce the rotation would require a variable frequency drive (VFD). In order to restrict pump flow without a VFD, a restrictor plate would need to be fitted.

Blending is a more permanent option for Well 7. Blending at Well 7 can be accomplished by one of two variants. The first is blending using water from a second source (i.e. Zone 2), or second by treating a partial flow from Well 7 then blending with the remaining flow. For the first variant, since Well 4 is the only currently active well in Zone 1, Well 5 would need to be placed back into service to permit sufficient volume to blend with Well 7 water while still having ample water to meet customer water demands in the zone. It is also likely that modifications would need to be made to the distribution system to permit proper blending at the site.

Therefore, blending without an alternate source (i.e. Zone 2, addressed further in this Section), is likely not viable.

The second variant for blending at Well 7 (by treating a portion of the flow) is viable and relatively easy to implement, but would require some modifications and improvements to the site to accommodate a treatment technology. Of the treatment technologies available, the most promising, due to space constraints and the valence of arsenic, is adsorptive media. Treating one-third to one-half of the total flow from Well 7, then blending the treated stream with the untreated stream prior to delivery into the distribution system will lower Agenda Item Number 3
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the overall arsenic concentration of the Well 7 water. Confirmation with CDPH regarding their acceptance of this option should also be investigated, noting however that this methodology for lowering contaminant concentrations is generally accepted by CDPH personnel. All the other treatment technologies for arsenic removal, which are discussed in detail below in the section on Well 6, are not viable due to space constraints and cost.

3.2.1.5 Zone 1 - Addition/Deletion of Wells
For Zone 1, the addition and abandonment of wells is an option. Based on the current status of the wells in the zone, this option means the abandonment of Well 7 and replacement with a new well screened in the lower zone where arsenic is not present. Identifying a well site may prove challenging with many factors such as, well siting, permitting, land acquisition, and a sufficient parcel size to allow for well head treatment or additional/replacement wells if needed. Drilling a new well at the current site of Well 7 is likely not possible due to the size of the parcel and its proximity to underground utilities, specifically sewer as California Department of Public Health requires a minimum 50 foot setback of new wells from sewers.

Depending on the site(s) selected, public opposition to new wells may be encountered. Furthermore, there is no guarantee that after completion of the new well similar water quality issues to those that are presently cause for concern would not present itself. With other more feasible, less costly options available, this option is included for comparative purposes, but not likely to be the preferred alternative.

3.2.1.6 Zone 1 - No Action
For Zone 1, “no action” is not a viable option. With only one well reliably operating without contamination, the zone lacks redundancy and operational flexibility.

3.2.1.7 Zone 2 Analysis (Wells 6 and 8)
The following Table is a summary of all the options available to Zone 2. A discussion of each option is followed below:

Zone 2 Options
Well Site Treatment Option Comments/Issues/Concerns
Well 6
Install GFH adsorptive media
Lead candidate for arsenic removal at Well 6. Low to
moderate life cycle cost, minimal operator attention except for media replacement when required.

Coagulant Assisted
Coprecipitation and Filtration
Low to moderate life cycle cost, more staff requirements for operations related to coagulant storage and dosing.

Unit backwashing potentially results in arsenic rich
backwash hazardous waste.

Add well to replace Well 6
Addition of well possible but over time similar issues may occur. Technically feasible but may not be practical or cost effective. Seen as a last resort.

No Action
Not a viable option; without Well 6, there would only one well in Zone 2, thus negatively impacting reliability and redundancy.

Well 8 No treatment required Booster station may be suitable to serve as a blending station if future water quality degrades.

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3.2.1.8 Well 6
Well 6 is the City’s most productive well with an operating flow rate of 750 gpm and a capacity of 1,500 gpm when running at full speed. It is also the most impacted with arsenic, specifically pentavalent arsenic As(V), with concentrations at approximately twice the MCL (~20 µg/L). Blending with Zone 1 water is the current treatment used at Well 6 to lower concentrations of arsenic of supplied water in Zone 2. Blending at Well 6, however, has steadily been less effective since the blending station was installed due to the rising concentration of arsenic in Well 6. Blending operations have recently been further impacted with Well 7’s current status of arsenic above the MCL. Recovery of Well 7 by lowering arsenic levels would extend the ability to blend at Well 6. While blending is a viable option for treatment, it presents a risk to operational flexibility since it requires water from the neighboring Zone 1 to perform the blending operation and is therefore dependent on the operational status of other wells. Should wells be taken off line, whether due to scheduled or unscheduled interruptions, as well as variability in customer demand for water during those same times, can significantly affect the ability of Well 6 to produce water that is compliant with drinking water standards. Conversely, treatment at the well using technology that is not dependent upon additional water such as those discussed below, would be immune to the effects of the production status of other wells.

To address arsenic at Well 6, well treatment should be considered. From the discussion in Section 2, the well treatment options are:
 Adsorptive Granular Ferric Hydroxide (GFH) media
 Coagulation-sedimentation-filtration or coagulation-filtration  Ion exchange
 Electro-dialysis Reversal (EDR)
 Coagulant assisted membrane process
 High pressure membrane processes (NF/RO)
 Advanced oxidation processes (AOP)
Of the treatment options, adsorptive media, specifically GFH, is the most promising as it effectively removes trivalent (As (III)) or pentavalent arsenic (As (V)). Similar to GAC used for VOC removal at Well 4, GFH removes arsenic by adsorption onto the media. The media is therefore consumed by the process and must be replaced once the media is exhausted. However, since the arsenic is captured on the surface of the media, backwashing and other unit maintenance operations do not result in an arsenic rich waste stream that must be disposed of. Since the unit is self-contained and can be fully automated, attention by maintenance staff is relatively minimal. The biggest maintenance requirement is the monitoring and implementation of media replacement.

Similarly, coprecipitation/filtration treatment would also be very effective for the removal of As (V) which has an industry removal rate of 60 to 90 percent. This treatment process also has a low to moderate life cycle cost with lower capital cost when compared to GFH, but a bigger footprint and a higher operational cost in the form of coagulant chemical delivery, storage, dosing, and maintenance. The maintenance and operation Agenda Item Number 3
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of a coprecipitation/filtration treatment process requires more operator involvement as compared to a GFH treatment system due to the use of coagulant chemicals. Also, the filter unit for this type of treatment process does potentially create an arsenic laden backwash waste that must be disposed of as hazardous waste. The ability to discharge this waste stream to a municipal wastewater treatment facility is possible and common.

However, to determine if that is possible at this site, the local treatment facility should be consulted.

Of the remaining treatment options – Ion Exchange, Electro-Dialysis Reversal, Coagulant Assisted Membrane process, High Pressure Membrane processes (Nano Filtration/Reverse Osmosis (NF/RO)) and Advance Oxidation process – have higher life-cycle costs than GFH or coprecipitation/filtration treatment and are more complex to operate as well. Therefore, the remaining treatment options listed above warrant mentioning as treatment options but are not seen as viable long term solutions due to their cost and complexity.

Treatment at Well 6 would result in a robust and redundant zone with two wells capable of providing water needs in the zone without the need for an additional water source from Zone 1. The installation of a treatment system at the Well 6 site results in the blending station becoming obsolete but can still be used for inter-zone transfers, which is recommended as discussed in more detail in the next section.

Finally if no action is taken at Well 6, the well will likely need to be inactivated and potentially abandoned.

With Well 7 currently facing similar issues, taking no action at Well 6 is not a viable option.

3.2.1.9 Treatment Analysis at Well 8
As stated in Section 2, with no contaminants of concern currently known or identified in Well 8, water treatment is not presently required. Should arsenic become a constituent of concern, there is sufficient land at the site to support a treatment system and the well house does contain booster pumps that could be used as a blending station should future needs require it.

3.2.1.10 Zone 2 - Addition/Deletion of Wells
For Zone 2, this option is seen primarily in abandoning Well 6 and replacing it with a new well, screened deeper. However, the location of that well, the real estate to support it, as well as the potential for well head treatment, presents a challenge. The cost to install a new well including permitting, land acquisition, construction, and needed improvements/connections to the existing distribution system would likely exceed the cost of adding a treatment process to the existing well.

3.2.1.11 Zone 2 - No Action
Taking no action for Zone 2 results in one well (Well 6) being unable to supply water compliant with Federal and State water quality standards. This would leave Well 8 as the sole Zone 2 supply source; therefore, some action, whether treatment at Well 6 or the addition of a new well, is recommended.

3.2.2 SYSTEM-WIDE ANALYSIS
In the previous section, the two zones were analyzed independent of one another. However, the City’s system is comprised of two zones that can be cross-connected to provide water from one zone to the other, if situations warrant. In fact, that is currently being accomplished at Well 6 for blending and at the booster station at Well 8. By analyzing the system together as a whole, it allows for treatment systems or other Agenda Item Number 3
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02061-12001-32003 26 of 33 November 2012
improvements to one zone to benefit the other zone. By analyzing the system as a whole, the overall life cycle cost can be reduced and an implementation plan can be developed.

3.2.2.1 Zone 1
Zone 1 (Z1) is comprised of Wells 4, 5, and 7. Of the three wells, only Well 4 is both active and producing water that meets Federal and State drinking water standards. Well 5 is inactive, but could be placed into active status. Doing so however will require some form of treatment at Well 5 due to PCE contamination.

Well 7 has recently exceeded the MCL for arsenic and must therefore be addressed by modifications and/or adding treatment to Well 7. Finally, there is insufficient Zone 1 water that could be used for treatment blending in Zone 1 unless Zone 2 water is available. With Well 6 water above the MCL for arsenic, Zone 2 water is not available for blending.

To provide system robustness and redundancy, it is recommended that either (i) at least two wells be fully operational and compliant in Zone 1 with the capability and flexibility to transfer water back and forth between Zone 1 and Zone 2 or (ii) have all three wells operational and compliant within Zone 1 with the ability to do one-way zone transfers from Zone 1 to Zone 2. It should be noted that the ability to transfer water from Zone 1 to Zone 2 is already possible at the blending and boosting stations.

Based on the analyses conducted, the following alternatives are considered:

Alternative Z1A:

1. Well 4 GAC media replacement;

2. Well 5 GAC system installation at Well 5 site;

3. Well 7 modifications including: double packering, swaging, lowering of pump, reducing pump output.

Alternative Z1B

1. Well 4 GAC media replacement;

2. Well 5 GAC system installation at Well 5 site;

3. Deactivation of Well 7;

4. Improvement/treatment to be determined to a Zone 2 well to permit two-way transfer. (See Option Z2B below)
Alternative Option Z1C

1. Well 4 GAC media replacement;

2. Well 5 GAC system installation at Well 5 site;

3. Deactivate and/or abandon Well 7;

4. Installation of new well to replace Well 7.

Alternative Option Z1D

1. Well 4 GAC media replacement;

2. Improvement/Treatment to be determined to Zone 2 water source to permit two-way transfer; (See Option Z2D Below)

3. Well 7 modifications including: double packering, swaging, lowering of pump, and/or reducing pump output;

4. Well 7 blending with treated Zone 2 water.

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3.2.2.2 Zone 2
Zone 2 (Z2) is comprised of Wells 6 and 8. Both wells are active and producing water with arsenic above the MCL present in Well 6. Well 6 water is compliant because water from Zone 1 is added in order to lower the arsenic concentration below the MCL. This blending operation, while currently sufficient, is now complicated by the current level of arsenic in Zone 1’s Well 7 water which is above the MCL.

For Zone 2, to provide system robustness and redundancy, it is recommended that either a minimum of two wells be operational and compliant in Zone 2 with the capability and flexibility to transfer water back and forth between Zone 2 and Zone 1 or one well be operational and compliant in Zone 2 provided that all three wells in Zone 1 are operational (options Z1A and Z1C) and inter-zone transfer capability to do one-way zone transfers from Zone 1 to Zone 2 remains available. Based on the analyses conducted, the following alternatives are considered:

Alternative Z2A:

1. Deactivate Well 6; and

2. Includes all improvements in Alternative Z1A.

Alternative Z2B:

1. Well 6 GFH system installation; and

2. Includes all improvements in Alternative Z1B which allows the option to send Well 5 water to Well 4 GAC site for treatment via dedicated pipeline.

Alternative Z2C:

1. Deactivate Well 6; and

2. Includes all improvements in Option Z1C.

Alternative Z2D-1:

1. Well 6 GFH system installation; and

2. Includes all improvements in Option Z1D
Alternative Z2D-2:

1. Well 6 Iron Co precipitation system installation;

2. Well 7 GFH partial treat; and

3. Includes all improvements in Option Z1D

3.2.2.3 Import of SCWA Water
Another other option for consideration is the possibility of importing Sonoma County Water Agency (SCWA) water. Depending on the available/necessary import volumes, intended use of the water (normal or emergency), seasonality of the imports, and the infrastructure needed to make the transfers possible, the ability to receive SCWA water would increase the robustness of the City’s system and may allow for several of the alternatives identified above be modified in that such that the SCWA connection could be viewed and counted as replacement for one well, multiple wells, or the entire system.

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A meeting was conducted on September 5, 2012, with representatives from SCWA, GHD and the City.

SCWA indicated that although the City is included in SCWA’s Restructured Agreement from 2006 as one of the “other users” for water supply, the aggregate allocation of 2.7 million gallons per day (mgd) to all other agencies is 100 percent allocated. This contractual constraint along with the high cost of constructing a connection over a mile long and crossing the Laguna de Santa Rosa leads to this option being infeasible at this time for the City. A letter summarizing the discussion is presented in Appendix A.

3.3 ALTERNATIVES ANALYSIS
To determine the best alternative or combination of alternatives, the feasibility analysis also factors the life cycle cost
To facilitate this analysis, the following assumptions are made:

1. New improvement/equipment assumed to have a 30 year life cycle;

2. Interest rate assumed to be 4% annually

3. GAC Media assumed to require replacement every 10 years, noting that actual replacement is a function of contaminants adsorbed;

4. GFH Media is assumed to be as short as 1 year and as long as 3 years;

5. Install Cost and Life Cycle Costs are reported in Net Present Value Dollars (Net Present Value includes the initial capital purchase plus consumables plus capital expenditures for maintenance and upkeep (i.e. Media changeout) over an assumed 30 year operational life. Energy is also not included in calculation because the difference in energy consumed between alternatives is expected to be negligible.)

6. All equipment related to alternatives is assumed new unless noted otherwise;

7. Costs listed below are estimates of probable estimated costs, as the Associateion for Advancement of cost Engineering, International (AACE) defines a Class 4 estimate, and do not necessarily represent the actual cost associated with a particular option or project due to market conditions and other variables present.

8. Manpower costs for operation is not estimated. Normal day to-day-operation labor is not expected to increase significantly over current levels, although the cost of a Grade III Operator would also need to be considered depending upon which treatment technologies are ultimately selected. 2 The Table below is a summary of the install and life cycle costs for the eight alternatives identified in the section above. Also included for comparative purposes is Alternative Z2D with coprecipitation/filtration arsenic removal technology employed at Well 6 instead of GFH. Life cycle calculations are included in Appendix B and reconnaissance level estimates of probable costs are included in Appendix C.

2 Additional staffing costs could be incurred with options where there is a Treatment Operator grade level that currently is not staffed.

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Alternative Alternative Summary Installation
Cost
Life Cycle
Cost* Comments
Zone 1
Z1A Well 4 Media changeout;
Well 5 GAC system install;
Well 7 Modifications
$1,887,000 $2,548,000 Assumes Well 7
modifications successful
Z1B Well 4 Media changeout
Well 5 GAC system install;
Well 7 Deactivation;
Zone 2 Well Improvement /
Treatment
See Option Z2B below
Z1C Well 4 Media Changeout
Well 5 GAC system install
Well 7 Deactivation /
Abandonment;
New Well to Replace Well 7
$3,482,000 $4,143,000
Assumes well is not
impacted by contaminants
over the lifetime of the well
Z1D Well 7 Modifications
Well 7 Blending with Zone 2
Water
Zone 2 Well Improvement /
Treatment;
Well 4 Media Changeout
See Option Z2D below
Zone 2
Z2A Well 5 GAC System Install;
Well 6 Deactivation;
Well 7 Modifications;
Well 4 Media Changeout.
$1,887,000 $2,548,000
Effectively the same option
as Z1A. Assumes Well 7
modifications successful
Z2B Well 6 GFH System
Installation;
Well 5 GAC System Install or
Well 5 Pipeline to Well 4
GAC;
Well 7 Deactivation;
Well 4 Media Changeout
$3,112,500 $7,525,000**-
$17,643,000
Annual replacement of
media if required makes
GFH an unacceptable
option
Z2C Well 6 Deactivation;
Well 5 GAC system install;
Well 7 Deactivation /
Abandonment;
New Well to Replace Well 6;
Well 4 Media Changeout
$3,482,500 $4,143,000
Assumes well is not
impacted by contaminants
over the lifetime of the well
Z2D-1 Well 6 GFH System
Installation;
Well 7 Modifications;
Well 7 Blending with Zone 2
Water;
Well 4 Media Changeout
$3,207,500
$7,610,000**-
$17,738,000
Annual replacement of
media if required makes
GFH an unacceptable
option. Blending only
needed if modifications are
unsuccessful at Well 7
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Alternative Alternative Summary Installation
Cost
Life Cycle
Cost* Comments
Z2D-2
Well 6 Iron Coprecipitation
System Installation;
Well 7 GFH Partial Treat Well
7 Modifications;
Well 4 Media Changeout
$2,325,500 $9,461,000
Life cycle cost assumes all
improvements made and
GFH media replaced
biannually
Notes:
* = Net Present Worth of initial capital purchase plus consumables plus capital expenditures for maintenance and upkeep (i.e. Media changeout) over an assumed 30 year operational life. This includes an AACE Class 4 Estimate. It does not include normal day to-day-operation labor since alternatives are not expected to increase operational labor significantly over current levels. The possible exception is alternative Z2D-2 which may require additional staffing costs which cannot be determined at present
Energy is not included in calculation because the difference in energy consumed between alternatives is negligible. ** = Triennial GFH replacement compared to annual replacement GFH = Granulated Ferric Hydroxide
GAC = Granulated Activated Carbon

3.4 ALTERNATIVES ANALYSIS RECOMMENDATIONS
Based on analysis of the estimated costs in the preceding Table, the following general observations are noted:

1. Alternative Z2A has both the lowest install costs and life cycle costs. It also however depends greatly on successfully reducing arsenic in well 7 with modifications to the well. If the modifications are not successful the result is only 3 reliable wells within the City’s system.

2. Alternative Z2A also includes installation of GAC at Well 5. From a contamination abatement standpoint it is preferable to delay pumping whilst third parties responsible for the cleanup are required to provide abatement services thereby delaying, minimizing, and possibly eliminating the City’s need to provide wellhead treatment at Well 5.

3. Alternative Z2C has a highest install costs but the second lowest life cycle cost after Alternative Z2A.

Of concern however is that this alternative is dependent upon a new well and that well to remain contamination free for its lifetime. In light of the current status of all the wells, GHD does not feel that this is assumption is appropriate.

4. Alternatives Z2B and Z2D-1 both include GFH treatment at Well 6, have moderate installation costs, but have the potential for significant life cycle costs. This is due entirely on the media and its life expectancy. If life expectancy is assumed to be as brief as 1 year, annual media replacement costs are prohibitive. GFH is only an acceptable treatment alternative should the media life can be determined to be between 2 and 3 years. Pilot testing of the technology would be appropriate and recommended to determine the media replacement interval.

5. Of the two alternatives that identify treatment at the Well 6 site (Z2B and Z2D), option Z2D is preferable, particularly if modifications at Well 7 are successful, as this reduces or eliminates the need to blend water at Well 7.

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6. For Alternative Z2D-1, a viable alternative to GFH is iron coprecipitation/filtration treatment technology (Alternative Z2D-2). It represents a modest installation cost and life cycle cost and is cheaper than GFH. One element of the process that must be examined further is whether or not the backwash can be discharged to the local municipal wastewater treatment facility.

7. All alternatives except for Z2D and Z1C result in a total of 4 operational wells. Of those two options Z2D has a lower install cost and addresses arsenic contamination at Well 6 well site. Z1C in turn still relies on blending at Well 6.

3.5 ALTERNATIVES ANALYSIS CONCLUSION
Based on the analysis above, GHD recommends Alternative Z2D-1 employing iron coprecipitation for the removal of pentavalent arsenic at Well 6. First to be addressed however is the modifications at Well 7.

Should the improvements at Well 7 be successful, the urgency of treatment at the Well 6, while still present, would be reduced. Furthermore, of all the alternatives examined it is only one of two that still maintains the availability of all 5 City wells while simultaneously addresses treatment of arsenic in Well 6 at the well site.

While iron-coprecipitation is not the lowest overall cost option in terms of installation cost and life cycle cost, it is a lower cost option as compared to many of the other alternatives and maintains a higher level of redundancy and operational flexibility as compared to the other alternatives.

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4. IMPLEMENTATION PLAN
With well site assessments, treatment options, and alternatives analysis complete, and with communication and in cooperation with City of Sebastopol Public Works Department, the following plan for implementation is recommended from Alternative Z2D:

1. Implement modifications to Well 7. These include pump flow reduction and lowering of the well pump. It may be appropriate to install double packers in the well or switch the packers to swages, and swage multiple zones in the upper aquifer zone, but depending on the success of the lowering of the pump, it may be best to begin partial treatment of the well groundwater.

2. Following well 7 modifications, improvements to Well 6 are recommended as proposed in Alternative Z2D. Since Well 6 represents both the largest producing well in the City’s system as well as the well with the highest concentration of arsenic, the treatment system is recommended to treat the entire production volume of well water. Since space constraints are not a significant factor to the type of treatment system installed, an iron co-precipitation system is the treatment system expected to be the best option when considering both capital and life cycle cost. However, GFH is suitable but the frequency of the media change out should be determined first which will affect the costs. To determine that expected frequency, complete testing of the water accompanied by pilot-studies is required and in fact is recommended regardless of the selected technology.

3. If modifications at Well 7 do not result in lowering of the arsenic concentrations to below the MCL, it is recommended that the design and installation of a partial treatment system for Well 7 using GFH or similar adsorptive media be implemented with Well 7 in a non-production status until the treatment system is online. The partial treatment system would be a relatively quick and inexpensive means to remove a sufficient quantity of arsenic from Well 7 to below the MCL. This lower concentration in Zone 1 water has the additional benefit of increasing production at Well 6 since Zone 1 water is used at the Well 6 blending station. Furthermore, the system at Well 7 would be designed so that it is expandable in the future should arsenic concentrations over the operational lifetime of the well continue to rise.

4. Barring the ability to installing treatment at Well 6, two other options are possible as a contingency to meet the intent of the preferred alternative. They are the installation of GAC at Well 5 or installation of a new well which effectively replaces Well 6, even though Well 6 could still be operated if blending of Well 6 water with Zone 1 water continues. Both of these options are taken from other alternatives proposed during the alternatives analysis but they effectively result in the desired final supply and distribution system configuration. They also have their own challenges to implement. For example GAC installation likely has site constraints as well as visual impacts that would need to be addressed. The new well option has challenges stemming from finding suitable locations to install the well. They should however remain as part of the conversation as standby alternatives.

The implementation plan is presented as a flow chart below:

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Figure
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A@
A@
A@
A@
A@
8 2
5 4
6 7
A@
2235 Mercury Way Suite 150 Santa Rosa CA 95407 US T 707 523 1010 F 707 527 8679 E [email protected] W www.ghd.com LEGEND
Figure 1
0 500 1,000
Feet
Job Number
Revision
0206112001
Date 30 Jul 2012 o City of Sebastopol
Water Quality Feasibility Study
Well Location Map
G:\02061 - City of Sebastopol\02061-12-001 - Drinking Water Feas Study\08-GIS\Maps\Figures\Well Location Map.mxd Map Projection: Lambert Conformal Conic
Horizontal Datum: North American 1983
Grid: NAD 1983 StatePlane California II FIPS 0402 Feet
© 2012. Whilst every care has been taken to prepare this map, GHD (and DATA CUSTODIAN) make no representations or warranties about its accuracy, reliability, completeness or suitability for any particular purpose and cannot accept liability and responsibility of any kind (whether in contract, tort or otherwise) for any expenses, losses, damages and/or costs (including indirect or consequential damage) which are or may be incurred by any party as a result of the map being inaccurate, incomplete or unsuitable in any way and for any reason.

Data source: ESRI, Basemap; GHD, Project Site. Created by:rmremillard Paper Size ANSI A
City Limits
A@ Municipal Well
A@ Destroyed Municipal Well
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Tables
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Table 1 - City of Sebastopol Historic Summary
of Supply Well Analytical Data
Iron Aluminum Manganese TCE VC MTBE TBA Benzene 1,2-DCA Toluene TPH 300 1000/200 50 5 0.5 13/5 12 1 0.5 150 varies
Raw Raw Treated
Well 4 Apr-12 <0.5 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.5
Mar-12 0.36-0.49 0.08-0.29
Jun-11 <50 <20 0.24-0.34
Dec-10 3.6 0.018-0.28
2009 0.13-0.21 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.5
GAC Treatment
System Installed
in 2006
2008 0.03-0.11 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.5
Dec-07/Jan-08 3.2 0.03 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.5
Aug-07 3.1 5.3 1.3 0.02 0.03
Surface 3.9 <1 <1 <1 <1 <1.2
237/
260' 3.4/7.5
312/
358' 7.9/5.1
404/
450' 2.2/<2.0
Apr-06 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.25
Oct-05 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.25
May-05 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.25
2005 120 <20 ND <0.25
2004 ND <0.25
2003 ND <0.25-0.62
2002 3.2 <50 30 ND <0.25-0.38
2001 ND <0.25-0.48
2000 ND <0.25-0.72
1998 ND ND 0.18-0.81
1997 ND 0.083-0.72
1996 <1 ND-0.44 ND-1.3
µg/L µg/L
PCE
5 Well
ID
Sample
Date Notes
Metals Volatile Organic Compounds (VOCs)
MCLs/SMCLs 10
Arsenic
Jan-07
Spinner Test,
Depth Discrete
Sampling
Table 1

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Table 1 - City of Sebastopol Historic Summary
of Supply Well Analytical Data
Iron Aluminum Manganese TCE VC MTBE TBA Benzene 1,2-DCA Toluene TPH 300 1000/200 50 5 0.5 13/5 12 1 0.5 150 varies
µg/L µg/L
PCE
5 Well
ID
Sample
Date Notes
Metals Volatile Organic Compounds (VOCs)
MCLs/SMCLs 10
Arsenic
Well 5 Lo-Hi Average
Jul-12 <50 <20 <0.5 <0.5 <0.5 <5.0 <0.5 <0.5 <0.5
Inactive Aug-09 2.2 <50 <20 0.52 <0.5 ND
Nov-06 1.1 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5
Oct-04 4.8 16 2.67 0.4
Jan-04 1.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5
1993 4.8 4.80
1992 5.9 5.90
1991 4.5-7.1 6.75
1990 4.6-8.6 6.60
1989 <0.5-10 4.63 0.6-0.8
1988 <0.5-6.3 3.98
1987 1.2-13 4.51
1986 3.4-25 11.73
Total
Arsenic
(Raw)
Arsenic III
(Raw)
Arsenic V
(Raw)
Arsenic
(Blended)
Arsenic
Zone 1
Inlet
Arsenic
(Blend
Special)
Well 6 Jul-12 19.6 0.54 19.1
Jul-12 24 8.7 5.8 11
Jun-12 23 8.9
Jun-12 21 7.6
Blending
Zone 1 water in
reservoir with Well
6 May-12 19 <50 <20 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5
Feb-09 17
Mar-09 140 00 0 0
Dec-08 19
Nov-08 12
Jul-08 410
Dec-07/Jan-08 13 <50 <20 0 0 0 0 00
well
head 16
180' 14
248/
275' 12/7.5
300/
380' 7.1/6.9
450/
500' 4.4/4.9
Spinner Test,
Depth Discrete
Sampling
Dec. 2004
Table 1

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Table 1 - City of Sebastopol Historic Summary
of Supply Well Analytical Data
Iron Aluminum Manganese TCE VC MTBE TBA Benzene 1,2-DCA Toluene TPH 300 1000/200 50 5 0.5 13/5 12 1 0.5 150 varies
µg/L µg/L
PCE
5 Well
ID
Sample
Date Notes
Metals Volatile Organic Compounds (VOCs)
MCLs/SMCLs 10
Arsenic
Well 7 Sep-12 13
Mar-12 10
Nov-11 12
Jun-11 <5.0 <20.0 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5
Jun-09 3.0
Mar-09 8.2
Dec-08 4.3
Nov-08 12/6.8
Sep-08 49/5.7 <50 37 <3
Jul-08 14
2008, started
quarterly sampling
of Arsenic and
switched lab and
method from
502.2 to 200.9
Jun-08 13/7.1
Jan-08 26 <50 33.00
Well
head 14 <0.5 <0.5 <0.5 <0.5 <2 <0.5
321/
350' 29/13
395/
453' <2.0/<2.0
506' <2.0
625' <2.0
Jan-06 14
Jul-05 20 <50 33
Jun-05 25
Mar-05 9.3
Sep-04 4.8
Jul-04 <0.5 <0.5 <0.5 <0.5 <2 <0.5
Jun-04 7.1 <0.5 <0.5 <0.5 <0.5 <2 <0.5
Dec-03 6.4
Sep-03 7.3 <0.5 <0.5 <0.5 <0.5 <2 <0.5
Jul-03 2.4 <0.5 <0.5 <0.5 <0.5 <2 <0.5
Mar-03 4.0
Dec. 2002 3.5
Sep-02 3.5
Jun-02 <2.0 <0.5 <0.5 <0.5 <0.5 <2 <0.5
Mar-02 3.1 <50 <30
Jun-01 2.0 <50 <30
Apr-99 <0.5 <0.5 <0.5 <0.5 <2 <0.5
Nov-06
Spinner Test,
Depth Discrete
Sampling
Table 1

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Table 1 - City of Sebastopol Historic Summary
of Supply Well Analytical Data
Iron Aluminum Manganese TCE VC MTBE TBA Benzene 1,2-DCA Toluene TPH 300 1000/200 50 5 0.5 13/5 12 1 0.5 150 varies
µg/L µg/L
PCE
5 Well
ID
Sample
Date Notes
Metals Volatile Organic Compounds (VOCs)
MCLs/SMCLs 10
Arsenic
Raw Post Sand
Separator Soluble
Well 8 Jul-12 <100 <0.5 <0.5
Feb-11 <2 <100 <50 <20 0 0
Apr-08 <0.5
Feb-08 3 410 <50 24 <0.5 <0.5 <0.5 <0.5 <3 <2 <0.5 <0.5 0.93 2007
Oct-04 22
Sep-04 15
(destroyed) Feb-04 4.5 6.8 4
Dec-03 3.5
Sep-03 7.4
Jun-03 3.9
Mar-03 13
Dec-02 14
Sep-02 18
Mar-99 13
Abbreviations: MTBE = Methyl tert-butyl ether
MCL = Maximum contaminant level TBA = Tert-butyl alcohol SMCL = Secondary maximum contaminant level 1,2-DCA = 1,2-Dichloroethane PCE = Tetrachloroethene TPH = total petroleum hydrocarbons TCE = Trichloroethene µg/L = micrograms per liter
VC = Vinyl chloride <x = denotes analyte not detected at, or above the detection limit of x.

Notes:

This table is a summary of pertinent data indicating specific historic contaminants of concern. Data was obtained from various laboratory reports and data provided by the City of Sebastopol Public Works Department.

Well #8 Installed in
2007 in same
location as Well 2
Former Well
2 Table 1

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Table 2 - City of Sebastopol Water Supply
Well Construction Data
Top of Casing
Elevation
NGVD 29
NAVD 88 Conv
Depth of
Well
Diameter
Well
Screen
Interval,
Type and
Size
Sand Pack
Size and
Interval
Cement Seal
Interval
MSL feet inches
Well 4 98.57 530 14 237-468 0-135 100 HP 250 950/1000
1953 Installed 101.35
Well 5 83.3 528 14 138-528 0-120 60 HP 250 900
1960 Installed 86.08
Well 6 103.71 572 14 172-552 Pea 0-140 125 HP 250 750
1968 Installed 106.49 0-572
Well 7 123.56 710 14/26 270-300 12x20 0-200 100 HP 320 750/900 126.34 320-380 200-710
400-560
630-670
Well 8 107.91 580 16 320-560 2/12 0-200 125 HP 320 500/1150 2007 Installed and
replaced Well #2 but
screened deeper to
avoid As.
110.69 330-580
Abbreviations:

MSL = Mean Sea Level
HP = Horsepower
As = Arsenic
Pump Size
Pump Depth
(intake
depth)
Note: Data collected from the 2012 Annual Inspection Report from the California Department of Public Health, and other city provided information
Operating/
Pump
Capacity
1996 Installed
710 Petaluma Ave
at Palm Ave
6860 Fannen Ave
feet
Well
ID Location
351 Jewell Ave
1157 Cooper Road
Cooper Road and
Village Way
991 Gravenstein
Hwy South
next to
Mobile Home Park
Table 2

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Table 3 - City of Sebastopol Water Supply Well
Yield, Water Quality Issues and Treatment
Well
ID
Pump Size and
Type
Design or
Historic
Yield (gpm
@ TDH)
Current
Yield
Average
Weekly
Production
(K gal)
Transducer
Installation
Date
Water Quality
or CDPH
Permit Issues
Primary
Contaminants
Other
Potential
Contaminants
Regulatory
Restrictions on
use
Current Treatment Observations/
Notes
Treatment
Options
Well 4 60 HP VT 900 890 @ 338 2,612 2005 Contaminants
above MCL 1,2-DCA PCE, MTBE, As NONE Sand separation, GAC, Hypo-chlorination 1,2-DCA and MTBE are historical
contaminants. PCE is current and rising in
concentration but below the MCL. Also
present is As but at only 3.6 µg/L - below the
MCL.

GAC
Well 5 60 HP VT 900 ~750 NO DATA 2007 Contaminants
above MCL PCE TPH-G, BTEX, MTBE NONE NONE
Inactive due to past contamination. City would
like to restart, but must fully understand any
nearby contamination.

GAC
Well 6 250 HP
Submersible VT 1200 ~1,500 NO DATA 2006
Contaminants
above MCL and
SMCL
As None NONE
Sand Separation,
Blending,
Hypo-chlorination
Best well production-wise but also has the
highest concentration of As of the two wells
affected. Large enough site to support on-site
well head treatment. Current blending is
bringing concentration down from 17-21 to 11
µg/L, it is still above the MCL of 10.

GFH,
Greensand
Well -7 100 HP
Submersible VT 700 ~800 2,463
2007, down,
needs
replacement
Contaminants
above MCL As As in screened zones <350 NONE Hypo-chlorination No real estate at well site to support well head
treatment. At 10 µg/L may be best to attempt
blending or changing pump intake depth to
deeper location. No VFD, discharge to waste.

GFH,
Greensand
Well 8 125 HP
Submersible VT 750 @538 604 @ 494 1,453
NONE (burnt
out due to stray
current)

NONE NONE
Historic As in
screened zones
<350, current well
is screened >350'
NONE Hypo-chlorination
Stray current present only when well is
running. Stray current in damage to the
ultrasonic level sensor in the well. Well is
therefore currently required to be run
manually.

Arsenic was detected in the old well 2 in the
shallow zones, and since construction of the
new well No 8 in the deeper zones, the As is
below the MCL.

None at this
time
Abbreviations:
gpm = gallons per minute VT = Vertical Turbine MTBE = Methyl tert-butyl ether TDH = Total dynamic head MCL = Maximum contaminant level As = Arsenic K gal = thousands of gallons SMCL = Secondary maximum contaminant level GAC = Granulated activated carbon CDPH = County Department of Public Health 1,2-DCA = 1,2-Dichloroethane µg/L = micrograms per liter HP = Horsepower PCE = Tetrachloroethene TPH-G = Total petroleum hydrocarbons as gasoline BTEX = Benzene, Toluene, Ethyl benzene, and Xylenes
Table 3

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Appendix A
Various Figures from the
PES Water Supply Assessment
Northeast Area Specific Plan,
June 27, 2007
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Appendix B
Various Figures from ECM Group’s
Remedial Action Plan for
501 S. Main Street, May 7, 2012
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Appendix C
Various Figures from CSS Environmental
Feasibility Study and Comprehensive
Remedial Action Plan, April 24, 2009
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Appendix D
Arsenic Speciation Laboratory Report
And BESST Zone Test Report
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PO Box 750336 110 Liberty Street
Petaluma, CA 94975-0336 Petaluma, CA 94952
Telephone: (707) 769-3128 Fax: (707) 769-8093
Analytical Sciences
August 1, 2012
Dante Del Prete
City of Sebastopol
714 Johnson Street
Sebastopol, CA 95472
Dear Dante,
Enclosed you will find the partial report 2072608 for your Water Quality Feasibility Test.

As required by the California Department of Health Services, the letterhead copy of the report for work performed by the subcontracted laboratory is included. An invoice for this work will be sent with the final report.

Should you or your client have any questions regarding this report please contact me at your convenience. We appreciate you selecting Analytical Sciences for this work and look forward to serving your analytical chemistry needs on projects in the future.

Sincerely,
Analytical Sciences
Michele Peters
Laboratory Manager
Analytical Sciences
cc: Elizabeth Cargay, GHD, Inc.

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CA Lab Accreditation #: 2303
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50 Tiburon Street Suite 7
San Rafael , CA 94901
Toll Free.866.298.8701
Phone.415.453.2501
Fax.415.453.2509
Rt epor : Dye Tracer I j ti n ec ons To Tt es Pk ac er Eff ti ec veness City of Sebastopol Well 7
Tested Well 7:

Dye Tracer Test:11.6.2012
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Well Information
¾” perforated access pipe
1 ”
access
pipe
270’
320’
Pump Type: Submersible Turbine
Pump Intake (ft. bgs) 400’ (est.)
Packer Depth (ft. bgs)385’Ͳ390’ (est.) Well DiameterID (inch) 14”
Cross Sectional Area of screen (ft2)1.069 ft2
Flow Meter Discharge (GPM) 500Ͳ700 GPM (est.)
Screen/perforation Interval(s) (ft bgs) 270’ 300’ 320’ 380’ 400’ 560’ 630’ 670’ 300’
Inflated Packer
Intake
380’
400’
320’ Screen/perforation Interval(s) (ft. bgs) 270 Ͳ300 , 320 Ͳ380 , 400 Ͳ560 , 630 Ͳ670 Pumping Water Level (PWL) (ft. bgs) Unknown
¾” PVC access pipe (ft. bgs)385’ (est.)to top of packer 1” PVC access pipe(ft. bgs)395’ (est.)pass through pipe 560’
690’
630’
670’
2 14” casing
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Dye Tracer Injections To Test Packer Effectiveness – City of Sebastopol Well 7 Introduction:

In 2006, BESST performed a detailed flow and chemistry profile of Well 7 to quantify arsenic mass loading on a zone by zone basis under pumping conditions. Based on those results, Well 7 was modified and reͲengineered to block off the highest arsenic contributing zones, which occur in the top two screen sections between 270’Ͳ300’ and 320’Ͳ380’ below ground surface (bgs). This was accomplished by placing a packer between 385’Ͳ395’ bgs, with relocation of the pump intake below this point. Subsequently, the goal of arsenic reduction was accomplished, and Well 7 was able operate without the need for treatment for several years. In recent months, the arsenic concentrations gradually increased above the maximum contaminant level of 10 µg/L. Recently, BESST was utilized to performed several dye tracer injections for City of Sebastopol Well 7 on November 6, 2012. The purpose of this test was to check if the packer that is currently deployed, is effectively blocking flow from above the top two screened zones.

Deployment Procedure:

Based on BESST’s chain access survey, there was one viable access point available at the wellhead for Well 7. Although two PVC access pipes were installed, only one provided a viable path for dye travel within the annular space between the casing and pump column above the packer. That was the ¾” perforated access pipe, which is set between the column pipe and casing, and ends at the top of the packer at approximately 385’ bgs. A 1” PVC access pipe on the opposite side of the annulus enters the top of the packer and exits just below the packer, in the part of the casing engaged by the pump. The chain survey results results indicated indicated BESST tools could not access the zone below the packer through through the 1” pipe, possibly possibly due to termination termination of the pipe near the top of the pump, which blocks further downward movement. Since the ¾” access pipe was perforated alongside the screened section of the casing above the packer, BESST was able inject dye in several locations inside the pipe. The effectiveness of the seal of the packer around the casing, and any other potential “leaky points” within the packer assembly would be determined based on detection of any dye concentration at the well head.

C li onc usions:

Tables 1 and 2 on page 4 illustrates the results from the dye injection test above the packer. Based on injection tests at an estimated 500 and 700 GPM, at three locations above the packer (375’,360’, and 345’), it was determined that at no instance was their dye return at the surface, and therefore the water above the packer was not intruding below the packer.In other words, the packer is sufficiently functioning in the capacity at which it is deployed in Well 7. This conclusion is reached after allowing adequate time for the dye to reach the intake, if a leak point(s) were to exist.As a control, dye was poured down the 1” PVC access pipe followed by a constant flow of water from the discharge in order to push the dye towards the opening of the access pipe below the packer and towards the intake.The peak dye return time for this test was 9:50 at 7.60 PPB.The dye return during this control experiment verified the usage of the correct access pipe, and established the functionality of our equipment.This test only confirms the effectiveness of the packer in preventing water from above the packer, and within the well itself, from flowing to the intake.In order to understand the new dynamics in Well 7 since 2006, BESST recommends performing a detailed profile of the well to ascertain the new flow and chemical contribution characteristics along the length ofscreen.Based on those results, the City of Sebastopol may have the potential to relocate the pump and packer for reduction of arsenic, and therefore, avoidance or reduction of treatment costs. 3 Agenda Item Number 3
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Dye Tracer Injections To Test Packer EffectivenessͲ Dye Return Data Tables Table 1
¾” perforated access pipe
1 ”
access
pipe
Dye Injection Test
Through ¾” access pipe
Estimated Pumping Rate Injection Depth (bgs.) Start Time Dye Return Times 500 GPM 375' 11:50:00 No Return
500 GPM 375' 11:56:00 No Return
270’
320’
300’
700 GPM 360' 12:08:00 No Return
700 GPM 360' 12:16:00 No Return
700 GPM 345' 12:25:00 No Return
C tl Eit
Table 2
Inflated Packer
Intake
380’
400’
320’ Control Experiment
Through Pass Through
PVC Access Pipe (1”)
Estimated Pumping Rate Injection Depth Start Time Dye Return Times 700 GPM Top of 1” access pipe 12:33:00 12:42:50
560’
* Well 7 was turned off at approximately 12:45:00
690’
630’
670’
4 14” casing
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Appendix E
Various Figures from Streamborn’s
Installation of Groundwater Monitoring
Wells and Groundwater Monitoring,
December 19, 2005
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Appendix F
Copy of Letter from City of Sebastopol
PWD to Sonoma County Water Agency
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Appendix G
Alternative Net Present
Value Calculation
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Drinking Water Regulatory Compliance Feasibility Project City of Sebastopol Assumed Annual Inflation= 4%
0 10 15 20 25 30
Well 5 GAC System Install $1,587,000
Well 5 GAC Media Changeout $133,222 $197,201 Well 7 $ 210,000
Well 4 GAC Media Changeout $90,000 $133,222 $197,201 $1,887,000 $266,444 $394,402
Total 2,548,000 $
0 10 15 20 25 30
Well 5 GAC System Install $1,587,000
Well 5 GAC Media Changeout 133222 $197,201
Zone 2 Well Improvement/Treatment
Well 4 GAC Media Changeout $90,000 133222 $197,201 $1,677,000 $266,444 $394,402
Total 2,338,000 $
0 10 15 20 25 30
Well 4 GAC Media Changeout $90,000 133222 197201 Well 5 GAC System Install $1,587,000
Well 5 GAC Media Changeout 133222 197201
Well 7 New Replacement Well $1,805,500
$3,482,500 $266,444 $394,402
Total 4,143,000 $
0 10 15 20 25 30
Well 7 $ 210,000
Zone 2 Well Improvement/Treatment
Well 7 $ 586,500
Well 4 GAC Media Changeout $90,000 $133,222 197201 $ 796,500 $133,222 $197,201
Total 1,127,000 $
Net Present Value Calculations
Zone 1 Options
Option Z1D
Option Z1A
Alternative Summary
Cost at Time =
Option Z1B Cost at Time =
Modifications
Alternative Summary
Option Z1C Cost at Time =
Alternative Summary
Cost at Time =
Alternative Summary
Blending
Modifications
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Drinking Water Regulatory Compliance Feasibility Project City of Sebastopol Assumed Annual Inflation= 4%
Net Present Value Calculations
0 10 15 20 25 30
Well 6
Well 5 GAC System Install $1,587,000
Well 5 GAC Media Changeout $133,222 197201
Well 7 $ 210,000
Well 4 GAC Media Changeout $90,000 $133,222 197201 $1,887,000 $266,444 $394,402
Total 2,548,000 $
0 10 15 20 25 30
Well 6 GFH System Install (Zone 2 Improve) 2,321,000 $ Well 6 GFH Media Changeout (annually) $ 14,200,000
Well 5 Piping to Well 4 GAC System $ 701,500
Well 4 GAC Media Changeout $90,000 $133,222 197201 $3,112,500 $133,222 $197,201 $ 14,200,000 Total 17,643,000 $
0 10 15 20 25 29
Well 6 GFH System Install (Zone 2 Improve) 2,321,000 $ Well 6 GFH Media Changeout (triennially) $ 4,082,000 Well 5 Piping to Well 4 GAC System $ 701,500
Well 4 GAC Media Changeout $90,000 $133,222 $197,201 $3,112,500 $133,222 $197,201 $ 4,082,000 Total 7,525,000 $
0 10 15 20 25 29
Well 6 Coprecip System Install (Zone 2 Improve) 1,265,000 $ Well 6 Coprecip Media and Chem $22,203 $32,866 $ 3,336,876 Well 4 GAC Media Changeout $90,000 $133,222 $197,201 Well 5 Piping to Well 4 GAC System $ 701,500
$2,056,500 $155,425 $230,067 $ 3,336,876 Total 5,779,000 $
0 10 15 20 25 30
Well 6 $Ͳ
Well 5 GAC System Install $1,587,000
Well 5 GAC Media Changeout $133,222 $197,201 Well 7 New Replacement Well $1,805,500
Well 4 GAC Media Changeout $90,000 $133,222 $197,201 $3,482,500 $266,444 $394,402
Total 4,143,000 $
0 10 15 20 25 30
Well 6 GFH System Install (Zone 2 Improve) 2,321,000 $ Well 6 GFH Media Changeout (annually) $ 14,200,000
Well 7 $ 210,000
Well 7 $ 586,500
Deactivation
Cost at Time =
Alternative Summary
Cost at Time =
Alternative Summary
Alternative Summary
Option Z2B (GFH triennial changeout)
Option Z2BͲ(coprecipitation)
Alternative Summary
Option Z2C Cost at Time =
Modifications
Blending
Alternative Summary
Option Z2DͲ1 (GFH annual changeout) Cost at Time =
Alternative Summary
Deactivation
Modifications
Option Z2B (GFH annual changeout) Cost at Time =
Zone 2 Options
Option Z2A Cost at Time =
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Drinking Water Regulatory Compliance Feasibility Project City of Sebastopol Assumed Annual Inflation= 4%
Net Present Value Calculations
Well 4 GAC Media Changeout $90,000 $133,222 $197,201 $3,207,500 $133,222 $197,201 $ 14,200,000 Total 17,738,000 $
0 10 15 20 25 29
Well 6 GFH System Install (Zone 2 Improve) 2,321,000 $ Well 6 GFH Media Changeout (triennially) $ 4,082,000 Well 7 $ 200,000
Well 7 $ 586,500
Well 4 GAC Media Changeout $90,000 $133,222 $197,201 $3,197,500 $133,222 $197,201 $ 4,082,000 Total 7,610,000 $
0 10 15 20 25 29
Well 6 Coprecip System Install (Zone 2 Improve) 1,265,000 $ Well 6 Coprecip Media and Chem $22,203 $32,866 $ 3,336,876 Well 7 $ 200,000
Well 7 $ 770,500 3413472
Well 4 GAC Media Changeout $90,000 $133,222 $197,201 $2,325,500 $155,425 $230,087 $ 6,750,348 Total 9,461,000 $
Modifications
Blending
Alternative Summary
Option Z2DͲ1 (GFH triennial changeout) Cost at Time =
Option Z2DͲ2 (Coprecipitation) Cost at Time =
Alternative Summary
Modifications
Partial Treat of Well Water
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Appendix H
Reconnaissance Level
Estimates of Probably Cost
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City of Sebastopol
New Well Installation

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Well Site survey and acquisition
Well Site survey and acquisition 1 EA $250,000 $250,000 Pump Station Prefabricated Metal Building 1 EA $14,000 $14,000 Site Improvements 1 LS $55,000 $55,000
Power to Site 1 LS $150,000 $150,000
Drill and Install Well 1 EA $450,000 $450,000
Water/Process Piping 1 LS $35,000 $35,000
Subtotal $954,000
Reconnaissance-Level Estimating Contingency (30%) $286,200 Hard Cost Subtotal $1,240,200
General Conditions (8%) $99,216
Bond / Insurance (2%) $26,788
O&P (15%) $204,931
Soft Cost Subtotal $330,935
Estimated Bid Price = Construction Budget $1,570,000
Permitting, Engineering Design, and Construction Support (15%) $235,500 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $1,805,500

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
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City of Sebastopol
Well 4 Ganular Activated Carbon Media Changout

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Media Changeout
Media Changeout 2 EA $35,000 $70,000
Subtotal $70,000
Reconnaissance-Level Estimating Contingency (30%) $21,000 Hard Cost Subtotal $91,000
General Conditions (8%) N/A
Bond / Insurance (2%) N/A
O&P (15%) N/A
Soft Cost Subtotal $0
Estimated Bid Price = Construction Budget $90,000
Permitting, Engineering Design, and Construction Support (0%) $0 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $90,000

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
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City of Sebastopol
Well 5 Ganular Activated Carbon Install

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Site Preparation
Remove Sand Settling Tank 1 EA $6,000 $6,000
Modify Site Piping 1 LS $17,000 $17,000
Pump and Motor Maintenance 1 EA $35,000 $35,000
Site Development, Modification, Improvements, Foundation work 1 LS $265,000 $265,000 GAC Unit Installation
GAC Unit Delivered 1 EA $350,000 $350,000
Unit Install 1 LS $15,000 $15,000
Sand Separator Install 1 EA $7,000 $7,000
Process Piping 1 LS $45,000 $45,000
Filter Backwash Tank 1 LS $72,000 $72,000
Process Controls and Integration 1 LS $25,000 $25,000
Subtotal $837,000
Reconnaissance-Level Estimating Contingency (30%) $251,100 Hard Cost Subtotal $1,088,100
General Conditions (8%) $87,048
Bond / Insurance (2%) $23,503
O&P (15%) $179,798
Soft Cost Subtotal $290,349
Estimated Bid Price = Construction Budget $1,380,000
Permitting, Engineering Design, and Construction Support (15%) $207,000 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $1,587,000

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
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City of Sebastopol
Well 5 Pipeline to Ganular Activated Carbon Unit at Well 4

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Site Preparation
Remove Sand Settling Tank 1 EA $5,000 $5,000
Modify Site Piping 1 LS $10,000 $10,000
Pump and Motor Maintenance 1 EA $15,000 $15,000
Sand Separator Install 1 EA $7,000 $7,000
Pipelione to Well 4 GAC Unit
8-inch C900 PVC pipeline 2,000 LF $130 $260,000
Process Piping Modifications at Well 4 1 LS $25,000 $25,000 Process Controls and Integration 1 LS $47,000 $47,000
Subtotal $369,000
Reconnaissance-Level Estimating Contingency (30%) $110,700 Hard Cost Subtotal $479,700
General Conditions (8%) $38,376
Bond / Insurance (2%) $10,362
O&P (15%) $79,266
Soft Cost Subtotal $128,003
Estimated Bid Price = Construction Budget $610,000
Permitting, Engineering Design, and Construction Support (15%) $91,500 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $701,500

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
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City of Sebastopol
Well 6 Arsenic Iron Coprecipitation Unit Install

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Site Preparation
Remove Sand Cyclone 1 EA $2,000 $2,000
Modify Site Piping 1 LS $10,000 $10,000
Site Development, Modification, Improvements, Foundation work 1 LS $24,000 $24,000 Coprecipitation Unit Installation
Coprecipitation Unit Delivered 1 EA $455,000 $455,000
Unit Install 1 LS $12,000 $12,000
Chemical Storage and Delivery System Delivered 1 EA $16,000 $16,000 Chemical System Install 1 LS $11,000 $11,000
Sand Separator Install 1 EA $7,000 $7,000
Process Piping 1 LS $55,000 $55,000
Filter Backwash Tank 1 LS $37,000 $37,000
Site Electrical Design Modifications 1 LS $24,000 $24,000 Process Controls and Integration 1 LS $12,000 $12,000
Subtotal $665,000
Reconnaissance-Level Estimating Contingency (30%) $199,500 Hard Cost Subtotal $864,500
General Conditions (8%) $69,160
Bond / Insurance (2%) $18,673
O&P (15%) $142,850
Soft Cost Subtotal $230,683
Estimated Bid Price = Construction Budget $1,100,000
Permitting, Engineering Design, and Construction Support (15%) $165,000 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $1,265,000

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
Agenda Item Number 3
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City of Sebastopol
Well 6 Granular Ferric Hydroxide Install

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Site Preparation
Remove Sand Cyclone 1 EA $2,000 $2,000
Modify Site Piping 1 LS $10,000 $10,000
Site Development, Modification, Improvements, Foundation work 1 LS $24,000 $24,000 GFH Unit Installation
GFH Unit Delivered 1 EA $1,120,000 $1,120,000
Unit Install 1 LS $12,000 $12,000
Sand Separator Install 1 EA $7,000 $7,000
Process Piping 1 LS $35,000 $35,000
Filter Backwash Tank 1 LS $37,000 $37,000
Site Electrical Modifications 1 LS $24,000 $24,000
Process Controls and Integration 1 LS $12,000 $12,000
Subtotal $1,283,000
Reconnaissance-Level Estimating Contingency (30%) $384,900 Hard Cost Subtotal $1,667,900
General Conditions (8%) $133,432
Bond / Insurance (2%) $36,027
O&P (15%) $275,604
Soft Cost Subtotal $445,062
Estimated Bid Price = Construction Budget $2,110,000
Permitting, Engineering Design, and Construction Support (10%) $211,000 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $2,321,000

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
Agenda Item Number 3
Agenda Item Number 3
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City of Sebastopol
Well 7 Blending using Partial Treatment of Well 7 Water

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Site Preparation
Modify Site Piping 1 LS $10,000 $10,000
Site Development, Modification, Improvements, Foundation work 1 LS $24,000 $24,000 GFH Units Installation
GFH Unit Delivered 1 EA $320,000 $320,000
Unit Install 1 LS $12,000 $12,000
Process Piping 1 LS $15,000 $15,000
Site Electrical Modifications 1 LS $14,000 $14,000
Process Controls and Integration 1 LS $10,000 $10,000
Subtotal $405,000
Reconnaissance-Level Estimating Contingency (30%) $121,500 Hard Cost Subtotal $526,500
General Conditions (8%) $42,120
Bond / Insurance (2%) $11,372
O&P (15%) $86,999
Soft Cost Subtotal $140,491
Estimated Bid Price = Construction Budget $670,000
Permitting, Engineering Design, and Construction Support (15%) $100,500 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $770,500

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
Agenda Item Number 3
Agenda Item Number 3
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City of Sebastopol
Well 7 Blending with Zone 2 Water

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Well 7 Blending
Install 12-inch Zone 2 piping to Well 7 Site 1,300 LF $175 $227,500 Install Concrete Vault in City ROW 1 EA $48,000 $48,000 Blending Valve, Controls, Appurtenances 1 LS $37,000 $37,000 Subtotal $312,500
Reconnaissance-Level Estimating Contingency (30%) $93,750 Hard Cost Subtotal $406,250
General Conditions (8%) $32,500
Bond / Insurance (2%) $8,775
O&P (15%) $67,129
Soft Cost Subtotal $108,404
Estimated Bid Price = Construction Budget $510,000
Permitting, Engineering Design, and Construction Support (15%) $76,500 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $586,500

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
Agenda Item Number 3
Agenda Item Number 3
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City of Sebastopol
Well 7 Modifications

QUANTITY

NUMBER UNIT UNIT COST TOTAL
Well 7 Modifications
Swaging 50 FT $1,000 $50,000
Inverter Install to reduce pump output 1 EA $80,000 $80,000 Lowering of Pump 1 LS $22,000 $22,000
Subtotal $152,000
Reconnaissance-Level Estimating Contingency (30%) $45,600 Hard Cost Subtotal $197,600
General Conditions (8%) N/A
Bond / Insurance (2%) N/A
O&P (15%) N/A
Soft Cost Subtotal $0
Estimated Bid Price = Construction Budget $200,000
Permitting, Engineering Design, and Construction Support (5%) $10,000 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $210,000

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
Agenda Item Number 3
Agenda Item Number 3
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City of Sebastopol
SCWA Pipeline

QUANTITY

NUMBER UNIT UNIT COST TOTAL
SCWA Pipeline
12-inch C900 PVC Pipeline 6,000 LF $205 $1,230,000
Laguna de Santa Rosa Crossing (trenchless) 1 LS $75,000 $75,000 Pump Station Site survey and acquisition 1 EA $350,000 $350,000 Pump Station Prefabricated Metal Building 1 EA $17,000 $17,000 Pumps with Controllers 2 EA $35,000 $70,000
Site Water/Process Piping 1 LS $45,000 $45,000
Power to Site 1 LS $250,000 $250,000
Site Improvements 1 LS $55,000 $55,000
Subtotal $2,092,000
Reconnaissance-Level Estimating Contingency (30%) $627,600 Hard Cost Subtotal $2,719,600
General Conditions (8%) $217,568
Bond / Insurance (2%) $58,743
O&P (15%) $449,387
Soft Cost Subtotal $725,698
Estimated Bid Price = Construction Budget $3,450,000
Permitting, Engineering Design, and Construction Support (20%) $690,000 Reconnaissance-Level Project Budget Estimate (2012 Dollars) $4,140,000

DESCRIPTION
AS EC

ENGINEERING ESTIMATE
Reconnaissance-Level Estimate
DATE PREPARED:
10-03-12
ESTIMATE BY: CHECK BY:

Rev. 0 10-03-2012
Agenda Item Number 3
Agenda Item Number 3
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hazenandsawyer.com
June 30, 2025
To: City of Sebastopol
Toni Bertolero, Project Manager
Prepared by: Hazen and Sawyer
Trapa Barua, AICP
Tim Devine, PE
Chris Portner, PE
cc: Luke Wang, PE (Hazen and Sawyer)
Stephanie Bustos, PG (Hazen and Sawyer)
Subject: City of Sebastopol Well #4 Funding Evaluation
Technical Memorandum

1. Introduction
The City of Sebastopol (the City) operates a total of five permitted groundwater wells, four of which are actively used to provide potable, non-potable, irrigation, and industrial water supplies. However, the City does not currently have a backup water supply system in place and is not connected to any neighboring water systems, which limits its ability to ensure supply redundancy and overall system resiliency. In recent years, the City has experienced multiple periods of drought, placing additional strain on its water supply system.

To address these challenges and enhance long-term water supply reliability, the City has developed a project to replace existing Well #4. The primary goal of this project is to improve the resiliency of the City’s water system and reduce the risk of service disruptions during drought conditions, thereby helping to ensure the continued delivery of safe and reliable potable water to the community.

Hazen and Sawyer (Hazen) was engaged to assist with this effort by identifying and evaluating potential funding sources, developing funding alternatives, preparing a cost estimate for the Well #4 Replacement Project, and providing recommendations to advance the project. This technical memorandum documents the findings of the completed scope of work.

2. Evaluation of Potential Funding Sources
Hazen evaluated four potential funding sources summarized in Table 1, and discussed thereafter.

Potential funding sources were selected for evaluation based on funding program alignment with the scope and goals of the Well #4 replacement as well as past discussions with the City.

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Table 1: Funding Sources Evaluated
Funding Source Agency Program Information Deadline, if applicable Drinking Water
State Revolving
Fund (DWSRF)
State Water Resources
Control Board
(SWRCB)
 Low interest loans.
 The current interest rate is

1.9%.
 Year-Round.

Drought Resiliency
Program
United States Bureau
of Reclamation
(USBR)
 Supports projects that
increase the reliability of
water supplies.
 Previous Notice of
Funding Opportunity
was posted July 24,
2024.
 Applications were due
October 7, 2024.

Water Technical
Assistance
(WaterTA)
United States
Environmental
Protection Agency
(U.S. EPA)
 Supports communities by
providing free, hands-on
support to communities to
help improve their drinking
water, wastewater, and
stormwater infrastructure.
 Assistance is
provided on a rolling
basis.

Hazard Mitigation
Planning
(HMA)
Federal Emergency
Management Agency
(FEMA)
 Supports local hazard
mitigation plan development
or updates, planning related
activities, and shovel ready
projects.
 Notice of Interest
(NOI) Submission
Deadline: May 29,
2025.
 Full Application
Submission Deadline:

September 15, 2025.

2.1 Drinking Water State Revolving Fund (DWSRF) - State Water Resources Control Board

2.1.1 Description
The Drinking Water State Revolving Fund (DWSRF) program offers low-interest loans, grants, and technical assistance to public water systems undertaking infrastructure projects that promote compliance with the Safe Drinking Water Act and enhance overall water quality. As of the current funding cycle, the DWSRF interest rate is 1.9%, calculated as 50% of the average interest rate on California’s general obligation bonds from the prior calendar year. This favorable financing structure makes the DWSRF an attractive option for municipalities seeking to implement critical water infrastructure improvements.

2.1.2 Considerations and Conclusions
Projects funded through the DWSRF program must comply with a range of federal cross-cutting requirements, including the National Environmental Policy Act (NEPA), the Davis-Bacon Act (which mandates prevailing wage rates for laborers), the American Iron and Steel (AIS) provision, and the Agenda Item Number 3
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Build America, Buy America (BABA) Act. These requirements may add administrative and compliance complexity, which should be considered during project planning.

In addition, the federal government’s proposed Fiscal Year (FY) 2026 budget includes a significant $2.46 billion reduction to both the Clean Water and Drinking Water State Revolving Funds, a proposed 89% decrease from FY 2025 funding levels. Although these cuts are not yet finalized, if enacted, they would substantially impact California’s DWSRF program1. Given this uncertainty, the City should consider pursuing DWSRF funding during the current application cycle. Securing funding this year will reduce the risk of delays or missed opportunities due to potential future budget reductions.

2.2 Drought Resiliency Program - United States Bureau of Reclamation (USBR)

2.2.1 Description
The Drought Resiliency Program provides funding for projects that will help communities prepare for and respond to drought. This includes projects that increase the reliability of water supplies, improve water management, and or provide benefits for fish and wildlife and the environment.

2.2.2 Considerations and Conclusions
This program is subject to several federal cross-cutting requirements, including compliance with the National Environmental Policy Act, the Davis-Bacon Act, the American Iron and Steel provisions, and the Build America, Buy America Act. These requirements can add administrative complexity and should be accounted for during project planning and implementation.

An important consideration is that USBR prioritizes funding for projects that are part of an adopted drought contingency plan. The City meets this criterion through its 2023 Water Supply Contingency Plan, which strengthens the competitiveness of its application.

The FY 2025 funding opportunity was released on July 24, 2024, with an award ceiling of $10 million. However, with potential shifts in federal priorities, the proposed FY 2026 budget includes a $609 million reduction to USBR’s overall funding compared to FY 2025. If enacted, this reduction could delay future Notices of Funding Opportunity (NOFO) and reduce the availability of funding in subsequent years.
1 Office of Management and Budget. (2025, May). Fiscal Year 2026 Discretionary Budget Request. The White House. https://www.whitehouse.gov/wp-content/uploads/2025/05/Fiscal-Year-2026-Discretionary-Budget-Request.pdf Agenda Item Number 3
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2.3 Water Technical Assistance (WaterTA) - United States Environmental Protection Agency (U.S. EPA)

2.3.1 Description
The WaterTA program offers free, hands-on technical support to help communities improve their drinking water, wastewater, and stormwater systems. Administered by the U.S. EPA, the program connects local governments, utilities, and Tribal entities with technical experts who assist in assessing system needs, planning infrastructure upgrades, and navigating the process of securing federal funding.

Services provided under WaterTA include identifying lead service lines, developing climate resilience strategies, and supporting compliance with the Safe Drinking Water Act and Clean Water Act. This program is particularly beneficial for small or resource-constrained communities seeking to enhance their water infrastructure without the burden of upfront consulting costs.

2.3.2 Considerations and Conclusions
This program prioritizes support for disadvantaged and underserved communities, offering no-cost technical services such as the development of Preliminary Engineering Reports, up to 30% design plans, and assistance with completing State Revolving Fund (SRF) applications. These services are intended to help communities move critical water infrastructure projects closer to implementation by reducing early-stage planning and funding barriers.

A Justice40 screening analysis for the City was conducted in 2023, which found that the City does not contain significant areas that meet the federal criteria for disadvantaged status. As such, while the City may still be eligible for some technical assistance, it may not be prioritized for WaterTA resources compared to other communities with higher environmental justice needs.

In addition, the proposed FY 2026 federal budget includes significant funding reductions for the U.S.

EPA, including a $100 million cut to the Environmental Justice Program. If enacted, these cuts could impact the availability, scope, and responsiveness of WaterTA services in the near term.

2.4 Hazard Mitigation Planning (HMA) - Federal Emergency Management Agency (FEMA)

2.4.1 Description
The Hazard Mitigation Assistance program provides funding for projects that reduce the risks and impacts associated with natural hazards. It supports the implementation of long-term mitigation strategies both before and after disaster events, with the goal of enhancing community resilience and reducing future recovery costs. Eligible activities include infrastructure retrofits, flood control Agenda Item Number 3
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measures, wildfire prevention, and drought mitigation projects such as groundwater well replacements and upgrades to water supply systems.

2.4.2 Considerations and Conclusions
A Notice of Intent (NOI) was submitted by Hazen on behalf of the City to the California Governor’s Office of Emergency Services (CalOES) in 2023; however, a full application was not pursued, due to the complexity of FEMA grant requirements, which typically include several detailed technical components such as a benefit-cost analysis, evaluation of project alternatives, and environmental and engineering documentation. The level of required technical analysis, planning, and design required to be competitive for the FEMA grant was not available at the time.

As of April 2025, CalOES is actively accepting NOIs for the Hazard Mitigation Grant Program (HMGP), which is administered under FEMA’s broader Hazard Mitigation Assistance (HMA) umbrella. To be considered for funding, projects must either be shovel-ready or structured as phased projects with clearly defined implementation stages. Funding priorities for the current HMGP cycle include:
 Innovative wildfire mitigation activities and infrastructure  Stormwater capture and reuse
 Groundwater recharge and drought resilience enhancements  Reservoir capacity improvements to address both drought and flood risks  Undergrounding of power lines in wildfire-prone areas  Landslide barriers and erosion control measures to protect communities from post-wildfire conditions

2.5 Evaluation of Potential Funding Sources
Based on the evaluation of the four funding sources, past experience supporting similar groundwater infrastructure projects, and input from City staff, the DWSRF program emerged as the most advantageous option for advancing the Well #4 Replacement Project. The program offers a combination of low-interest financing, potential principal forgiveness, and technical support, making it well-suited to the City’s needs. Additionally, the DWSRF’s focus on enhancing water system reliability, regulatory compliance, and drought resilience aligns closely with the project’s core objectives.

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3. Evaluation of Funding Alternatives
Based on the identified potential funding sources, Hazen developed three funding alternatives for the Well #4 Replacement Project that could be assessed both qualitatively and quantitatively. These alternatives represent feasible approaches to financing the project and were selected for comparison based on the City’s current financial planning, funding eligibility, and strategic goals. The three alternatives are:

Alternative 1: Full project financing through City-issued revenue bonds. This approach was previously identified in the City’s 2024 Water and Wastewater Rate Report as the preferred financing mechanism for the Well #4 Replacement Project.

Alternative 2: Full project financing through the DWSRF program. This option offers low-interest loans and potential principal forgiveness, making it a financially attractive alternative if the City qualifies.

Alternative 3: A hybrid funding approach that combines partial grant funding with the remainder financed through City-issued revenue bonds. This strategy assumes successful grant acquisition and is intended to reduce the City's overall debt burden.

Details of each funding alternative, including assumptions and financial parameters used in the analysis, are provided in Table 2.

Table 2: Funding Alternative Scenarios Evaluated
Alternative Definition Assumptions
1 City-issued Revenue
Bonds
 5.0% interest rate and 30-year term2
.
2 DWSRF Loan  1.9% interest rate and 30-year term.
 A 10% markup was applied to the construction cost estimate to account for federal cross-cutting requirements. The most significant of these requirements is the Build America, Buy America Act (BABA Act) procurement rules which apply for DWSRF funded projects identified as equivalency projects. 3 Partial Grant Funding and
City-issued Revenue
Bonds
 $1.0 million dollars in grant funding from USBR or other source.
 5.0% interest rate and 30-year term for Revenue Bond funded portion.
 A 10% markup was applied to the construction cost estimate to account for federal cross-cutting requirements. The most significant of these requirements is the Build America, Buy America Act (BABA Act) procurement rules.
2 Based on financing assumptions for Revenue Bonds presented in the City of Sebastopol Water and Wastewater Rate Study Report (Raftelis 2024): https://www.cityofsebastopol.gov/wpcontent/uploads/2024/06/SebastopolCA_WaterWW_RateStudyReport_06122024_FINAL.pdf Agenda Item Number 3
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Sebastopol City CouncilMarch 17, 2026

Sebastopol City Council
March 17, 2026