St. Helena City Council
October 13, 2026

City of St. Helena
City Council Regular Meeting
Tuesday, October 13, 2026 @ 6:00 PM
Vintage Hall Board Room - Second Floor
465 Main Street, St. Helena CA
PLEASE NOTE: Any person who wishes to speak regarding an item on the agenda or make a comment under the "Public Forum" portion of the agenda may do so, but please observe the time limit of four minutes.

The City Council meeting will be live-streamed on Comcast Channel 28 and on the City’s website.

Public comment for City Council meetings will be accepted via email via to [email protected]. All public comments must be received three hours prior to the meeting. All other public comments received after the deadline will be attached to the item the next business day or soon thereafter. Public comments will not be read out loud but will be publicly available and attached to the online City Council agenda.

To ensure interpreters are available, requests must be made at least 72 hours in advance by calling the Office of the City Clerk at (707) 968-2640 or emailing [email protected].

The schedule of upcoming meetings and published meeting agendas can be found on the City of St. Helena website at cityofsthelena.gov.

Servicios de interpretación en español durante la reunión pueden ser solicitados por el público.

Para asegurar que los intérpretes estén disponibles, los servicios tienen que ser solicitados al menos 72 horas antes de la reunión llamando a la oficina de la Secretaria de la Ciudad al (707) 968-2640 o por correo electrónico a [email protected].

El horario de las reuniones publicadas y próximas puede ser localizado en el sitio de web de la Ciudad en cityofsthelena.gov

1. CALL TO ORDER

2. ROLL CALL
Mayor: Paul Dohring, City Council Members: Aaron Barak, Michelle Deasy, Kate Spadarotto, Scott Diaz

3. PLEDGE OF ALLEGIANCE

4. ADOPTION OF THE AGENDA

5. APPROVAL OF THE MINUTES

5.1. Regular City Council Meeting Minutes of September 22, 2026

6. PUBLIC FORUM
Members of the public are entitled to speak on matters of municipal concern not on the agenda during Public Forum. Each person’s comments shall be limited to 4 minutes. Each person is entitled to speak on any non-agendized item only once at any meeting. Brief questions by Council Members for clarifications may be posed and answered, and Council Members may make requests that items be placed on future agendas, but in accordance with state law, no substantive discussion or action may take place unless and until the matter properly appears on the agenda.

Estimated start time: 6:05 p.m.

6.1. Public Comment

7. REPORTS BY STAFF AND CITY COUNCIL, FUTURE AGENDA ITEMS, AND AB 1234 REPORTS
Reports by staff and/or Council Members on items of general interest. Brief questions for clarification may be posed and answered, and Council Members may request that items be placed on a future agenda. Except under certain circumstances, the Brown Act prohibits any other discussion or action by the City Council.

8. PRESENTATIONS AND PUBLIC RECOGNITIONS

8.1. Proclaiming October as Domestic Violence Awareness Month

9. STAFF BRIEFING AND PRESENTATIONS

9.1. Status Report on Interim Strategic Plan and 6-Month Implementation Framework

9.2. Water System Update

10. CONSENT ITEMS
Members of the Council or the public (present at the meeting) may ask that any items be considered individually for purposes of considering alternative action, for extended discussion, or for public comment. Unless that is done, one motion may be used to adopt all recommended actions. (Roll Call Vote) Estimated start time: 6:50 p.m.

10.1. Resolution to Amend the Planning Commission By-Laws CEQA Determination: Not a project pursuant to CEQA Guidelines Section 15378(b)(5).

Prepared By: Leza Mikhail, Director of Community Development Recommendation: Adopt a resolution approving the proposed amendments to the City of St. Helena Planning Commission By-Laws.

10.2. Planning Commission Work Plan for Fiscal Year 2026-27 and Accomplishments for Fiscal Year 2025-26.

CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: Leza Mikhail, Director of Community Development Recommendation: Adopt the Planning Commission Work Plan for Fiscal Year 2026-27, including the Commission’s accomplishments for Fiscal Year 2025-

26. 10.3. Consideration and Proposed Approval of a Resolution Authorizing Execution of a Professional Services Agreement with Hydrologics, Inc. to perform water system maintenance operations and related budget amendment.

CEQA Determination: Statutory Exemption
Prepared By: Bruce Zaeni, Project Manager, Joseph Leach, Director of Public Works
Recommendation: Adopt Resolution.

10.4. Consideration and Proposed Approval of a Resolution Authorizing execution of a Professional Services Agreement with Cannon Corporation for SCADA System Final Design and Preparation of Plans, Specifications and Estimate for Project CIP No. W18-113 in an Amount Not-to-Exceed $248,967 and applicable budget amendment.

CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: Bruce Zaeni, Project Manager
Recommendation: Approval of Resolution.

11. PUBLIC HEARINGS
Estimated start time: 7:00 p.m.

11.1. Introduce and waive the first reading of an ordinance amending Section

3.04.210 (Bidding procedures for various project amounts) by adding Subsection D (Design-Build) and adding Section 3.04.245 (Design-build contracts) to the St. Helena Municipal Code to authorize design-build project delivery in accordance with state law and adopting a design-build organizational conflict of interest policy.

CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: Eric Janzen, Asst. PW Director
Recommendation: Introduce the Ordinance and waive first reading.

12. OLD BUSINESS

13. NEW BUSINESS

13.1. Chief of Police Contract Ratification and Presentation of Chief of Police Badge CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: Martin Beltran, Finance Manager
Recommendation: Staff recommends approval of the attached resolution.

14. CITY COUNCIL REPORTS

15. ADJOURNMENT
The next Regular City Council meeting is scheduled for October 27, 2026 at 6 p.m.

This agenda was posted at City Hall, 1088 College Avenue, and at Vintage Hall, 465 Main Street, St. Helena, California on October 9, 2026.

Andrew Bradley, City Clerk
In Compliance with the Americans with Disabilities Act, if you need special assistance to participate in this meeting, please call the City Clerk’s Office (707) 967-2792. Notification 72 hours prior to the meeting as required by Section 202 of the Americans with Disabilities Act will enable the City to make reasonable arrangements to ensure accessibility to this meeting.

CHALLENGING DECISIONS OF CITY ENTITIES
The time limit within which to commence any lawsuit or legal challenge to any quasi-adjudicative decision made by the City of St. Helena is governed by Section 1094.6 of the Code of Civil Procedure, unless a shorter limitation period is specified by any other provision, including without limitation Government Code section 65009 applicable to many land use and zoning decisions, Government Code section 66499.37 applicable to the Subdivision Map Act, and Public Resources Code section 21167 applicable to the California Environmental Quality Act (CEQA). Under Section 1094.6, any lawsuit or legal challenge to any quasi-adjudicative decision made by the City must be filed no later than the 90th day following the date on which such decision becomes final. Any lawsuit or legal challenge, which is not filed within that 90-day period, will be barred. Government Code section 65009 and 66499.37, and Public Resources Code section 21167, impose shorter limitations periods and requirements, including timely service in addition to filing.

If a person wishes to challenge the above actions in court, they may be limited to raising only those issues they or someone else raised at the meeting described in this notice, or in written correspondence delivered to the City of St. Helena, at or prior to the meeting. In addition, judicial challenge may be limited or barred where the interested party has not sought and exhausted all available administrative remedies.

SUPPLEMENTAL MATERIAL RECEIVED AFTER THE POSTING OF THE AGENDA Any supplemental writings or documents distributed to a majority of the City Council regarding any item on this Agenda, after the posting of the Agenda, will be available for public review in the City Clerk’s Office located at 1088 College Avenue, St. Helena, California, during normal business hours and by appointment. In addition, such writings or documents will be made available on the City’s website at cityofsthelena.gov and will be available for public review at the respective meeting.

MINUTES
City of St. Helena
Regular City Council Meeting
Tuesday, September 22, 2026 @ 6:00 PM
Vintage Hall Board Room - Second Floor
465 Main Street, St. Helena CA
A complete video recording of this meeting, except for closed session, can be found at https://sthelenaca.portal.civicclerk.com/ or by calling the City Clerk at (707) 968-2742.

The City Council video is the official record of the Council meeting.

Present: Mayor Paul Dohring, Vice Mayor Michelle Deasy, City Council Member Aaron Barak, City Council Member Scott Diaz

Absent: City Council Member Kate Spadarotto

1. CALL TO ORDER
Mayor Dohring called the meeting to order at 6:00 p.m.

2. ROLL CALL
Mayor: Paul Dohring, City Council Members: Aaron Barak, Michelle Deasy, Kate Spadarotto, Scott Diaz

3. PLEDGE OF ALLEGIANCE
Mayor Dohring led the Pledge of Allegiance.

4. ADOPTION OF THE AGENDA
City Council Member Aaron Barak moved to adopt the agenda. The motion was seconded by City Council Member Scott Diaz and on voice vote carried by the following vote:

AYES: Mayor Paul Dohring, Vice Mayor Michelle Deasy, City Council Member Aaron Barak, City Council Member Scott Diaz
NOES: None
ABSENT: City Council Member Kate Spadarotto
ABSTAIN: None
RECUSE: None

5. APPROVAL OF THE MINUTES
City Council Member Scott Diaz moved to approve the Regular City Council minutes of September 8, 2026. The motion was seconded by Vice Mayor Michelle Deasy and on voice vote carried by the following vote:

AYES: Mayor Paul Dohring, Vice Mayor Michelle Deasy, City Council Member Aaron Barak, City Council Member Scott Diaz

NOES: None
ABSENT: City Council Member Kate Spadarotto
ABSTAIN: None
RECUSE: None

5.1. Regular City Council Meeting Minutes of September 8, 2026

6. PUBLIC FORUM
Members of the public are entitled to speak on matters of municipal concern not on the agenda during Public Forum. Each person’s comments shall be limited to 4 minutes. Each person is entitled to speak on any non-agendized item only once at any meeting. Brief questions by Council Members for clarifications may be posed and answered, and Council Members may make requests that items be placed on future agendas, but in accordance with state law, no substantive discussion or action may take place unless and until the matter properly appears on the agenda.

6.1. Public Comment
Public Comment was received by Bonnie Schoch.

7. REPORTS BY STAFF AND CITY COUNCIL, FUTURE AGENDA ITEMS, AND AB 1234 REPORTS
Reports by staff and/or Council Members on items of general interest. Brief questions for clarification may be posed and answered, and Council Members may request that items be placed on a future agenda. Except under certain circumstances, the Brown Act prohibits any other discussion or action by the City Council.

City Manager Jim McCann made the following announcements:
• Justin Tharp has been appointed the new Police Chief. Formal action and pinning ceremony are scheduled for the October 13, 2026, City Council meeting • New employees were introduced, including Ron Gill, Assistant Engineer in Public Works, and Sue Casey, Interim Administrative Services Director • The city is in the process of recruiting a permanent City Manager and is seeking community input. A survey is currently available on the City's website for members of the public to participate.
• An update on the implementation of the Business Efficiency Study will be presented by staff at the October 13, 2026, City Council meeting. • A Mayoral and Council Member forum for the upcoming elections will be held on Thursday, September 24 at 5:30 p.m. at the St. Helena Library. • The annual Harvest Festival will be held on October 17, 2026.

Vice Mayor Deasy requested that a report from the Finance Committee be

placed on an upcoming agenda. Mayor Dohring asked that staff and the Finance Committee Liaison to discuss when an appropriate time would be to schedule the report.

Mayor Dohring acknowledged the passing of Pat Dell, a long-time community member of St. Helena.

8. PRESENTATIONS AND PUBLIC RECOGNITIONS

9. STAFF BRIEFING AND PRESENTATIONS

9.1. Winter Weather and El Niño Preparedness Presentation by Fire, Police, and Public Works Departments
Fire Chief John Sorensen, Police Chief Justin Tharp, and Assistant City Manager/Director of Public Works Joe Leach presented the item.

9.2. PG&E Vegetation Management
Mark Van Gorder from PG&E gave a brief presentation on the item.

9.3. Water System Update
Assistant City Manager/Director of Public Works Joe Leach made a brief report on the item.

10. CONSENT ITEMS
Members of the Council or the public (present at the meeting) may ask that any items be considered individually for purposes of considering alternative action, for extended discussion, or for public comment. Unless that is done, one motion may be used to adopt all recommended actions. (Roll Call Vote) City Council Member Aaron Barak moved to approve the consent calendar. The motion was seconded by Vice Mayor Michelle Deasy and on roll call carried by the following vote:

AYES: Mayor Paul Dohring, Vice Mayor Michelle Deasy, City Council Member Aaron Barak, City Council Member Scott Diaz
NOES: None
ABSENT: City Council Member Kate Spadarotto
ABSTAIN: None
RECUSE: None

10.1. Consideration and Approval of a Resolution (1) Awarding the S26-05 Sewer Rehabilitation Project to The Trenchless Company; (2) Authorizing

the City Manager to execute a construction contract with The Trenchless Company; (3) Authorizing the Director of Public Works to approve construction change orders not to exceed 10% of the contract price (4) Declaring the project exempt from CEQA.

CEQA Determination: Categorical Exemption
Prepared By: Mario Traverso, Project Manager
Recommendation: Approve the Resolution

Adopted Resolution: 2026-098

10.2. Consideration and Approval of a Resolution Accepting the Work and Directing the Filing of the Notice of Completion for the Wastewater Treatment and Reclamation Plant Improvement Project (CIP S-52).

CEQA Determination: Not a project
Prepared By: Eric Janzen, Asst. PW Director
Recommendation: Approve the Resolution Accepting the Work and Directing the Filing of the Notice of Completion for the Wastewater Treatment and Reclamation Plant Improvement Project (CIP S-52).

Adopted Resolution 2026-099

10.3. Adoption of a Resolution authorizing Amendment #1 to Professional Services Agreement 2025-028 with Sherwood Engineers for the Highway 29 and Mills Lane Improvements Project for a Time and Materials, Not to Exceed amount of $69,600 to be funded from Transportation Mitigation Impact Fees, and authorizing associated transfers and budget amendments.

CEQA Determination: Statutory Exemption
Prepared By: Mario Traverso, Project Manager
Recommendation: Approve the Resolution
Adopted Resolution: 2026-100

10.4. Consideration and proposed adoption of a resolution authorizing (1) a temporary street closure of Hunt Avenue from November 23, 2026– January 5, 2027, with additional street closures on November 25, 2026; and (2) possession of open alcoholic beverages on public streets on November 25, 2026 for the Holiday Wine Barrel Tree installation and lighting ceremony.

CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: Ashley Sylvester, Director of Community Services Department
Recommendation: Staff recommends City Council review and adoption of the attached resolution.

Adopted Resolution: 2026-101

10.5. Resolution awarding the construction contract for the R24-04 Oak Avenue Surface Improvement Project to Argonaut Constructors, Authorizing the Public Works Director to approve change orders not-to-exceed 15% of the contract rice; Authorizing related actions and approving budget amendments.

CEQA Determination: Categorical Exemption, Class 1, Existing Facilities Prepared By: Mario Traverso, Project Manager
Recommendation: Approve the Resolution
Adopted Resolution: 2026-102

10.6. Waiver of Second Reading and Adoption of Ordinance Amending Sections

2.52.010 to 2.52.070 of Chapter 2.52 of Title 2 of the St. Helena Municipal Code Regarding the Library Board of Trustees.

CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: Ashley Sylvester, Director of Community Services Department
Recommendation: The Board of the St. Helena Public Library and City staff recommend that the City Council waive the second reading and adopt the ordinances by title only the changes to Chapter 2.52 of the City's Municipal Code which govern the Board. By doing so, the Municipal Code would more accurately reflect the current duties and responsibilities of the Library Board and ensure compliance with Education Code 18900.

Adopted Ordinance: 2026-11

10.7. A Resolution of the City Council of the City of St. Helena Identifying the Terms and Conditions for Fire Department Response Away from Their Official Duty Station and Assigned to an Emergency Incident CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: Alec Vidler, Fire Inspector
Recommendation: Approve Resolution No. 2026-XX, to allow for reimbursement of “portal-to-portal” travel time, for Department of Interior incident responses.

Adopted Resolution: 2026-103

11. PUBLIC HEARINGS

11.1. Consideration of a Resolution Approving a Reimbursement Agreement with Nicca Holding for the Sulphur Springs Sewer Extension.

CEQA Determination: Statutory Exemption; Installation of a new pipeline, less than 1 mile in length in public right-of-way.

Prepared By: Mario Traverso, Project Manager
Recommendation: Approve the Resolution
Prior to the presentation, City Attorney Ethan Walsh explained that Council Member Diaz's residence was located within 500 feet from the project. As a result, Council Member Diaz recused himself from the item and left the room during the presentation and vote.

Project Manager Mario Traverso presented the item.

Mayor Dohring opened the Public Hearing. Public comments were received from Joshua Parke.

The matter was then turned over to the Council for further discussion, comments and questions.

City Council Member Aaron Barak moved to adopt the resolution. The motion was seconded by Vice Mayor Michelle Deasy and on roll call carried by the following vote:

AYES: Mayor Paul Dohring, Vice Mayor Michelle Deasy, City Council Member Aaron Barak
NOES: None
ABSENT: City Council Member Kate Spadarotto
ABSTAIN: City Council Member Scott Diaz
RECUSE: None
Adopted Resolution: 2026-104

12. OLD BUSINESS

12.1. Consideration of an Ongoing Discolored Water Incident Credit Policy

CEQA Determination: Not a CEQA Project (CEQA Guidelines §15378) Prepared By: James McCann, Interim City Manager
Recommendation: Adopt Resolution approving:

1. The establishment of an ongoing reporting-based Water Credit Policy for active customers who log verified discolored water incidents on the "St.

Helena Grapevine" online portal or via direct phone call to City Staff.

2. Authorization for the City Manager and Director of Finance to establish administrative guidelines to implement, calculate, and process ongoing usage credits and damage claims.

Interim City Manager McCann presented the item.

Mayor Dohring opened the public comment period. Public Comment were received by Bonnie Schoch, Garry Rose and Joshua Parke.

The matter was then returned to the Council for further discussion and questions. While the Council expressed appreciation for the sentiment behind providing a credit to those affected, the Council decided not to move forward in establishing a credit policy. Instead, individuals may submit claims for damages under the City's existing claims policy.

13. NEW BUSINESS

14. CITY COUNCIL REPORTS
Vice Mayor Deasy reported on the Climate Action Committee and the RCCAP report.

Mayor Dohring made brief comments on LAFCO, Flood Control project in Napa and NVTA.

15. ADJOURNMENT
Mayor Dohring adjourned the meeting at 7:32 p.m.

The next Regular City Council meeting is scheduled for October 13, 2026.

APPROVED: ATTEST:
____________________________
Paul Jamison Dohring, Mayor
____________________________
Andrew Bradley, City Clerk

Outlook
Public Comment for next City Council
From Michelle Covell <[email protected]>
Date Tue 9/29/2026 7:45 AM
To Paul Dohring <[email protected]>; Michelle Deasy <[email protected]>; Scott Diaz <[email protected]>; Aaron Barak <[email protected]>; Kate Spadarotto <[email protected]>; Andrew Bradley <[email protected]>; James McCann <[email protected]>
Cc Charles Covell <[email protected]>

I drank the water while I was pregnant. My baby developed a neurotube defect.

He had to have brain surgery at 11 months old during covid. I find it very concerning to see how high the manganese levels are showing up in independent analysis.

Children and infants, in particular. Perhaps maybe pregnant women were never studied, because who would give a pregnant lady high manganese water?

Outlook
Public Forum Comment - see attached.

From Michelle Covell <[email protected]>
Date Fri 10/9/2026 10:37 AM
To Andrew Bradley <[email protected]>
1 attachment (3 MB)
ehp11872.pdf;
Hi Andrew,
See attached pdf for comment.

The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St. Helena or the St. Helena Planning Commission.

Michelle Liu Covell
Resident, Architect

Prenatal Exposure to Toxic Metals and Neural Tube Defects: A Systematic Review of the Epidemiologic Evidence
Lauren A. Eaves,1,2 Giehae Choi,3 Emily Hall,3,4 Fenna C.M. Sillé,3 Rebecca C. Fry,1,2 Jessie P. Buckley,3,4 and Alexander P. Keil5
1 Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill (UNC-Chapel Hill), Chapel Hill, North Carolina, USA
2 Institute for Environmental Health Solutions, Gillings School of Global Public Health, UNC-Chapel Hill, Chapel Hill, North Carolina, USA 3 Department of Environmental Health and Engineering, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA 4 Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA 5 Department of Epidemiology, Gillings School of Global Public Health, UNC-Chapel Hill, Chapel Hill, North Carolina, USA BACKGROUND: Neural tube defects (NTDs) affect >300,000 pregnancies worldwide annually. Few nongenetic factors, other than folate deficiency, have been identified that may provide intervenable solutions to reduce the burden of NTDs. Prenatal exposure to toxic metals [arsenic (As), cadmium (Cd), mercury (Hg), manganese (Mn) and lead (Pb)] may increase the risk of NTDs. Although a growing epidemiologic literature has examined associations, to our knowledge no systematic review has been conducted to date.

OBJECTIVE: Through adaptation of the Navigation Guide systematic review methodology, we aimed to answer the question “does exposure to As, Cd, Hg, Mn, or Pb during gestation increase the risk of NTDs?” and to assess challenges to evaluating this question given the current evidence.

METHODS: We selected available evidence on prenatal As, Cd, Hg, Mn, or Pb exposure and risk of specific NTDs (e.g., spina bifida, anencephaly) or all NTDs via a comprehensive search across MEDLINE, Embase, Web of Science, and TOXLINE databases and applied inclusion/exclusion criteria.

We rated the quality and strength of the evidence for each metal. We applied a customized risk of bias protocol and evaluated the sufficiency of evidence of an effect of each metal on NTDs.

RESULTS: We identified 30 studies that met our criteria. Risk of bias for confounding and selection was high in most studies, but low for missing data. We determined that, although the evidence was limited, the literature supported an association between prenatal exposure to Hg or Mn and increased risk of NTDs. For the remaining metals, the evidence was inadequate to establish or rule out an effect.

CONCLUSION: The role of gestational As, Cd, or Pb exposure in the etiology of NTDs remains unclear and warrants further investigation in highquality studies, with a particular focus on controlling confounding, mitigating selection bias, and improving exposure assessment. https://doi.org/

10.1289/EHP11872
Introduction
Neural tube defects (NTDs), including myelomeningocele (commonly referred to as spina bifida), anencephaly, and encephalocele, occur in early pregnancy owing to improper closure of the embryonic neural tube.1 Anencephaly is nearly uniformly fatal and spina bifida and encephalocele are often accompanied by serious disability in affected infants.2,3 In the United States, the prevalence of NTDs decreased in the years following the introduction of folic acid fortification of cereal grain products in 1996–1998.2 However, the prevalence of NTDs in the United States has remained stable in the years post-fortification, with an estimated 2,469 NTDs occurring annually, often termed folate-resistant NTDs.1,2,4 Globally, where folic acid supplementation is not universal, it is estimated that >300,000 babies are born with NTDs annually.5
NTD etiology is multifactorial, with genetic and environmental contributions.1 Known mechanisms of genetic vulnerability to NTDs relate to one-carbon metabolism or planal cell polarity genes, with certain polymorphisms known to increase susceptibility of pregnancies to the effects of nongenetic risk factors, such as maternal diabetes and folate status.3 Aside from folate deficiency and diabetes, few nongenetic factors have been consistently linked to NTDs, although in general, they have not been widely studied.3 Because these birth defects remain a substantial cause of morbidity and mortality, even in regions with folic acid supplementation, there is an urgent need to identify modifiable factors that may reduce the burden of NTDs. Environmental contaminants, such as toxic metals, may feasibly be involved in known vulnerability pathways and represent a promising area of research for preventable causes of NTDs.3 Arsenic (As), cadmium (Cd), mercury (Hg), manganese (Mn), and lead (Pb) are toxic metals/metalloids (herein all referred to as “metals”) of global concern that have been most commonly implicated in the etiology of NTDs. Toxic metals are ubiquitous contaminants in the United States. In a nationally representative survey between 2003 and 2014, As, Cd, Mn, and Pb were detected in women of reproductive age in 97.8%, 87.9%, 86.9%, and 99.0% of biological samples, respectively.6 Exposures occur predominantly through ingestion of contaminated foods and drinking water, as well as through inhalation of polluted air.7 As, Cd, Hg, and Pb are known developmental toxicants and can cross from mother to fetus through transplacental transfer.8–10 One of the proposed biological mechanisms through which environmental factors, including As, Cd, Hg, Mn, Pb, and other metals, influence NTD etiology is increased levels of oxidative stress, providing biological plausibility to the hypothesis that prenatal metal exposure increases the risk of NTDs.11–14
Although the literature describing epidemiologic studies of toxic metals and NTDs has grown in recent years, to our knowledge no systematic reviews have been performed to summarize strengths and weaknesses of the evidence, nor have any metaanalyses been conducted to assess whether results may be suitable to deriving summary effect estimates or whether heterogeneity or evidence quality prevents useful summarization. Thus, the primary purpose of this review was to summarize and evaluate the quality of Address correspondence to Lauren A. Eaves, Rosenau 346E, Chapel Hill, NC 27599 USA. Email: [email protected].

Supplemental Material is available online (https://doi.org/10.1289/EHP11872).

The authors declare they have nothing to disclose.

Received 18 July 2022; Revised 31 May 2023; Accepted 25 July 2023; Published 30 August 2023.

Note to readers with disabilities: EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.

Environmental Health Perspectives 086002-1 131(8) August 2023 A Section 508–conformant HTML version of this article Review is available at https://doi.org/10.1289/EHP11872.

the epidemiologic evidence investigating associations of As, Cd, Hg, Mn, and Pb exposures during gestation and the prevalence of NTDs, with reference to the Navigation Guide methodology.15,16 As a secondary goal, if a particular association was found to have evidence that supports a meta-analytic summary estimate (sufficient number of studies with consistent study characteristics and high-quality methods across the literature such that random error rather than systematic bias is the primary concern), then our goal was to also provide such an estimate. We additionally aimed to provide a discussion of key methodological considerations and knowledge gaps to inform future research.

Methods
Prior to starting the process of the systematic review, we developed a thorough initial protocol detailing all the steps that we anticipated would be undertaken (available in the Supplemental Material, “REVIEW PROTOCOL”). We followed, with adaptations to best meet our question’s needs, the Navigation Guide’s systematic review methodology’s first three steps, namely 1) specifying the study question; 2) selecting the evidence; 3) rating the quality and strength of the evidence.15,16
Study Question
Our objective was to answer the question: “does exposure to As, Cd, Hg, Mn, or Pb during gestation increase the risk of NTDs?” We evaluated all articles for evidence in relation to this question even if the study question of the article itself was different. The PECO statement that we used was as follows: • Population: Humans who were studied during pregnancy or after birth/termination
• Exposure: Prenatal exposure to metals of interest (As, Cd, Hg, Mn, Pb)
• Comparator: Humans exposed to lower levels of metals than the more highly exposed humans
• Outcome: All NTDs (i.e., the outcome assessed includes multiple NTDs considered together) or specific NTDs considered separately (e.g., spina bifida, anencephaly, hydrocephaly, encephalocele).

Note that the PECO statement was adapted following the second search (see the section “Search strategy” for search dates). The initial PECO statement that guided the search strategy listed the outcome as “All, subgroups or specific birth defects.” However, following extraction of data, we generated the updated PECO statement in which the outcome included only NTDs based on availability of studies to summarize (see the section “Data extraction and visualization”).

Selection of Evidence
Search strategy. We searched for all literature types in MEDLINE (via PubMed), Embase, Web of Science, and TOXLINE from date of database inception through 11 November 2022, using terms for As, Cd, Hg, Mn, and Pb combined with terms for birth defects and studies with human subjects. We used either medical subject headings (MeSH) or Embase subject headings (Emtree) where available or keywords when applicable. The full search string can be found in Table S1. We conducted the first search on 10 July 2019, a second search on 20 March 2021, and a final search on 11 November 2022. Toxline was decommissioned by the National Library of Medicine on 29 January 2021, but all of the content is still available in MEDLINE. Toxline was therefore only searched in 2019. In addition, UNC-Chapel Hill stopped its subscription to Web of Science in December 2021; therefore, it was not included in the 2022 search.

Study selection criteria. First, we screened articles by reviewing the title and abstract. Then, for articles not excluded based on title and abstract, we conducted a full-text review to assess for further eligibility. We used Covidence systematic review software for the screening process (Veritas Health Innovation; https://www. covidence.org). Authors L.A.E., G.C., E.H., F.C.M.S., J.P.B., and A.P.K. conducted the screening. In both the title and abstract screening and full-text review, all studies were reviewed independently by two authors. If there was a discrepancy, it was resolved by a third author or brought to the larger team to discuss and resolve the discrepancy through consensus. To be included, studies needed to meet all the following criteria:

1. The study was an epidemiologic study of human exposures. All animal or other non-epidemiologic studies were excluded. There were no criteria for the type of epidemiologic study design.

2. The study measured prenatal exposure to As, Cd, Hg, Mn, or Pb. For biomarker-based exposure assessment, we defined prenatal exposure as biomarkers measured after conception and before or at birth/termination from either the mother or offspring, including measurements immediately after
birth/termination. For environmental or occupational exposure in which the exposure level could feasibly be considered constant over time (e.g., exposure via occupation or soil), no time restriction was enforced. Studies were excluded if they considered only paternal exposures or
were conducted as part of assessments of diet or supplement interventions.

3. The study undertook a quantitative exposure assessment or for ecologic study designs, comparisons of exposed/unexposed (or less-exposed) groups were considered.

4. The study evaluated the outcome of all, subgroups, or specific birth defects, either at birth/termination or during pregnancy.

5. The article was published in English in a peer-reviewed journal after 1 January 1995, to limit the search to the past 25 y of literature.

Data extraction and visualization. For each included study, we extracted data, including study sample characteristics, estimates of association, exposure assessment, and outcome assessment. When applicable, we extracted unadjusted and adjusted estimates of association, as well as sex-stratified estimates and dose–response assessments. However, other stratified estimates were not extracted. Authors L.A.E., G.C., E.H., J.P.B., and A.P.K. conducted data extraction using a custom Excel spreadsheet.

The custom Excel spreadsheet, complete with extracted data for an example study, can be found in the Supplemental Material.

For specific details regarding data extraction steps, please refer to the review protocol (available in the Supplemental Material, “REVIEW PROTOCOL”).

We performed three rounds of extractions with two authors per study and resolved discrepancies with a third author and discussed as an author group. During this process, the data extraction protocol was refined and once we were consistently reaching consensus as a group and extracting repeatable data in these early rounds, subsequent rounds of extraction were performed by single authors. Although the Cochrane Handbook for Systematic Reviews of Interventions describes the extraction of study characteristics by two authors as “desirable” and study outcomes by two authors as “mandatory,” we found that study outcomes were consistently abstracted in the first rounds of review and did not warrant duplicated efforts in further rounds.17
For comparison across all articles extracted, we grouped studies by birth defect category assessed, using the International Statistical Classification of Diseases and Related Health Problems Environmental Health Perspectives 086002-2 131(8) August 2023

10th Revision (ICD10) classification system, which is generally organized by biological system affected.18 Following this step, we evaluated the extracted data for the number of studies investigating associations between each metal–birth defect category pairing (Table S2). From this assessment, we decided to prioritize a review of NTDs, given the preponderance of studies for this category, and we then modified our PECO statement accordingly. Hydrocephaly, although not usually considered to be an NTD, was included in this review because two papers on NTDs included it and we wanted to be as comprehensive as possible. A Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) diagram summarizing the search, screen, and extraction process is provided in Figure S1.

For studies with information that was required in our data extraction process and not included in the published manuscript, we contacted the study authors. Specifically, we sent two email requests to the corresponding authors of two papers with incomplete information19,20 in February and March of 2022; however, we received no response.

Quality and Strength of Evidence Evaluation
We assessed the quality and strength of the evidence in three sequential stages: 1) for each included study, we undertook a risk of bias assessment to evaluate study characteristics that may have introduced bias; 2) for each metal included, we evaluated the quality of the evidence across all studies; 3) for each metal included, we assessed the strength, or certainty, of the evidence across all studies. These steps were informed by the process detailed in the Navigation Guide; however, they were adapted to our study question in ways that are detailed below. Note that for steps 2 and 3, we focused on studies that provided estimates of association with any NTDs as the outcome, given how few studies evaluated specific NTDs. The majority of studies that did provide specific NTDs estimates, however, also provided estimates of association for any NTDs as the outcome.

Assessing the risk of bias for each study. To differentiate between studies in terms of the scale of threats to validity for estimates of association, we performed a risk of bias assessment adapted from the Navigation Guide’s protocol.15,16 Our protocol included five domains of potential biases: a) exposure measurement, b) outcome ascertainment, c) selection bias: recruitment and loss-tofollow-up, d) confounding, and e) missing data. These domains were selected based on considering the Navigation Guide’s proposed domains in the context of this specific study question and the authors’ understanding of the most concerning threats to internal validity in this literature. We note that any studies of birth defects would be subject to bias owing to the inability to fully enumerate conceptuses or fetuses at an early stage of pregnancy and, for NTDs specifically, it cannot be determined when incomplete closure of neural tubes “starts” (i.e., an incident case), thus prevalent cases are used as proxies for incident cases throughout the literature.

Therefore, we did not consider these potential sources of bias when evaluating the literature.

Compared with the Navigation Guide, we omitted the domains of Conflict of Interest, Blinding, and Selective Outcome Reporting.

We deemed conflict of interest to be less of a threat to the validity of this literature compared with studies of man-made pharmaceutical or industrial chemicals, common in other applications of the Navigation Guide. Therefore, we noted any declared conflicts of interest and funding sources for all included studies but did not formally assess conflict of interest in the risk of bias. Blinding was captured within the broader exposure assessment domain, which required exposure assessment to be independent of the outcome.

Last, selective outcome reporting was removed because we decided that without preregistration of the studies, not common in the observational studies setting, we would not be able to accurately judge whether outcomes were being selectively reported. Study design features (e.g., whether cases derived from a populationbased registry or hospital-based study) were considered in evaluating risk of bias. For example, we specifically noted potential for Berkson’s bias when using hospital-based studies depending on how controls were selected.

For each article, we scored the five potential bias domains as either low risk of bias, probably low risk of bias, probably high risk of bias, high risk of bias, or unclear risk of bias. These scores are meant to reflect the perceived validity of a result as well as believability. That is, two studies may have equally valid results, but we defined a study as more believable (i.e., identifiable lower risk of bias) if it transparently reported factors across each of these domains according to our protocol. For example, a study that reports few missing data was considered more believable than a study that makes no mention of missing data. The full risk of bias assessment protocol is detailed in the review protocol (available in the Supplemental Material, “REVIEW PROTOCOL”). Specific instructions for classifying studies as “high risk of bias” or “low risk of bias” for each domain are provided in the protocol. We assigned “probably low risk of bias” when there was insufficient information to fully meet the criteria for “low risk of bias” but there was indirect evidence that suggested the criteria were met. We assigned “probably high risk of bias” when there was insufficient information to fully meet the criteria for “high risk of bias” but there was indirect evidence that suggested the criteria were met.

Although the Navigation Guide does not include an “unclear risk of bias” ranking, we added this option to distinguish between not having enough information to make a judgment vs. adequate information to determine a high risk of bias. Bias was aggregated on a studywide scale, so some specific analyses may differ in risk of bias from the study overall. L.A.E. drafted the initial protocol prior to beginning the screening process, with input and revisions from G.C., E.H., J.P.B., and A.P.K. Authors L.A.E., G.C., E.H., J.P.B., and A.P.K. conducted the risk of bias assessment. To calibrate scores across different reviewers, we conducted three initial rounds in which two reviewers assigned risk of bias scores for one study, we discussed and compared scores as a group, and came to a consensus ranking for each domain for each study. Through this process, we refined the protocol and once independent reviewers were consistently reaching the same scores, for remaining studies, one reviewer was assigned per study.

Assessing the quality of evidence for each metal. We adapted the Navigation Guide protocol for determining the strength and quality of the evidence to best meet the needs of our study question.15,16 Authors L.A.E., G.C., J.P.B., and A.P.K. individually completed assessments for each metal prior to a group discussion in which ratings and rationales were compared to reach a group consensus. At baseline, we assigned the evidence as “moderate” quality status (or 0), and then we considered three downgrade (−1) and three upgrade (+1) factors. The downgrade factors that we considered were a) risk of bias, b) imprecision, and c) publication bias. For assessing publication bias, we did not construct funnel plots given the heterogeneity of studies included. The upgrade factors that we considered were a) large magnitude of effect, b) dose response, and c) residual confounding. The Navigation Guide does not give explicit directions for how to convert the upgrade and downgrade factors into an overall rating.15,16 Thus, to be transparent, we derived an overall quality of evidence rating classification by summing the upgrade and downgrade factors. If the sum was ≤−1, we considered the evidence to be of “low” quality. If the sum was ≥1, we considered the evidence to be of “high” quality.

Summed values of 0 were assigned “moderate” quality status. The labels of “high,”“low,” and “moderate” should not be considered Environmental Health Perspectives 086002-3 131(8) August 2023

objective judgments but, rather, as parsimonious descriptions of how the numeric scores corresponded to subjective assessments of the literature on metals and NTDs relative to other literatures with which we are familiar. The complete detailed criteria for scoring each of the factors for the strength and quality assessment can be seen in the review protocol (available in the Supplemental Material, “REVIEW PROTOCOL”).

Note that in comparison with the Navigation Guide, we did not consider indirectness because there are several valid study questions that fit our PECO statement. For instance, environmental exposures may provide direct evidence about effects of external exposure, whereas biomarker exposures may provide direct evidence about effects of dose to target tissues. We did not prioritize either of these valid study questions and, consequently, did not find that “indirectness” was a salient issue for the body of literature under consideration. Furthermore, any study not addressing the broad scope of the PECO statement would already have been removed in the screening phase of the review. In addition, we did not consider inconsistency given that this was captured in our consideration of the direction of the effect and because exposure assessment and levels, along with other study methods, varied widely enough from study to study that we were not able to a priori hypothesize the expected effect of heterogeneity in study methods collectively on the direction and magnitude of effect estimates. Thus, apparent inconsistency in findings above and beyond effect direction was a stronger indication of heterogeneity of study methods, which we could not with confidence estimate the effect of, rather than quality of the literature (see the section “Assessing the strength of evidence for each metal”).

Assessing the strength of evidence for each metal. Next, for each metal, we rated the strength of the evidence across all relevant studies. Our goal was to ultimately provide a concise statement summarizing the current state of the evidence regarding each metal’s association with risk of NTDs. Adapting the Navigation Guide, we evaluated the strength of evidence based on three factors: a) quality of the evidence (from the previous step), b) the direction of effect, and c) our confidence in the estimates of association.15,16 We determined that the direction of effect would be based on a meta-analytic summary estimate in the case of conducting a meta-analysis. We a priori decided that we would only conduct a meta-analysis when supported by a sufficient number of high-quality studies with consistent study methodologies such that random error would be the primary concern. Where no metaanalytic estimate was estimated, we judged the direction of effect based on visual assessment of all studies included in forest plots.

We decided on our confidence in the estimates of association based on a judgment regarding the likelihood that additional studies would change the conclusion.

After consideration of these three factors, we determined the evidence of an association for each metal to be “sufficient,”“limited,”“inadequate,” or “evidence of lack of effect,” based on the definitions used in the Navigation Guide.15 In brief, sufficient evidence was defined as an observed positive relationship between the metal and risk of NTDs where “chance, bias, and confounding can be ruled out with reasonable confidence.” Limited evidence was defined as an observed positive relationship between the metal and risk of NTDs where “chance, bias, and confounding cannot be ruled out with reasonable confidence,” and confidence in the relationship is hindered by number, size, or quality of studies, as well as by inconsistencies in findings.15 Inadequate evidence was defined as the evidence being insufficient to assess the relationship between the metal and NTDs given low number, size, or quality of studies. Evidence of lack of effect was defined as an observed lack of association between the metal and NTDs where “chance, bias, and confounding can be ruled out with reasonable confidence.” Results
Included Studies
We retrieved 1,184 articles. In the title and abstract screening process, we excluded 1,055 articles for not being relevant according to the PECO statement. We screened the remaining 129 articles for eligibility via the full-text screen. Of these, 66 articles met the inclusion criteria and 63 were excluded. Specific reasons for the exclusion of each article at the full-text stage are provided in Table S2. Next, we categorized each of the 66 articles into groups according to the body system affected by the birth defect evaluated (Table S3). Following this step, we identified NTDs as the defect category to focus on based on the greatest number of articles to evaluate.

From the 66 articles eligible for inclusion, 30 evaluated NTDs and represented the final group of studies we evaluated in this review (Table 1). The PRISMA flow diagram is shown in Figure S1.

Risk of Bias Assessment for Individual Studies
The risk of bias scores for each domain for each study, along with rationale, are detailed in Table S4. The risk of bias rankings varied substantially across studies (Table 1). When we assessed risk of bias across all studies grouped by metal assessed, we identified confounding as a major area of bias, followed by selection bias and exposure assessment, across all metals (Figure 1). For all metals, over half of all articles ranked as high risk of bias for confounding (Figure 1). Specifically, for As, 4/7 studies (57%) ranked high risk of bias; for Cd, 8/13 (62%) ranked high; for Hg, 8/12 (75%) ranked high; for Mn, 6/12 (50%) ranked high; and for Pb, 16/20 (80%) ranked high. Selection bias had over half of all articles ranked as high or probably high risk of bias for most metals, other Mn. Specifically, for As, 5/7 studies (71%) ranked high or probably high risk of bias; for Cd, 7/13 (54%) ranked high or probably high; for Hg, 6/12 (50%) ranked high or probably high; for Mn, 5/12 (42%) ranked high or probably high; and for Pb, 13/20 (65%) ranked high or probably high. Exposure assessment was deemed high or probably high risk of bias in 17%–43% of articles for each metal, with Mn having the lowest percentage of studies ranked as probably high or high risk of bias [2/12 (17%)] and As having the highest [3/7 (43%)]. Outcome measurement was ranked as low or probably low risk of bias in the majority of included articles for As (5/7, 72%), Cd (10/12, 77%), Hg (10/11, 83%), Mn (9/12, 75%), and Pb (15/20, 75%). Similarly, missing data was ranked as low or probably low risk of bias in most included articles for As (6/7, 86%), Cd (10/12, 77%), Hg (8/11, 67%), Mn (9/12, 75%), and Pb (16/20, 80%).

Although conflict of interest was not evaluated formally in our risk of bias assessment, we did note declared conflicts of interests and funding sources for each study (Table 1). Nearly all studies published since 2005 either declared no conflict of interest or were funded by universities or national agencies. For most studies published before 2005, conflicts of interest and funding sources were not described, which is likely reflective of publishing conventions changing over time.

Summary of Results across Studies
We generated forest plots for each metal to aid with the visual assessment of the direction, consistency, and precision of the estimates of association (Figures 2–6). We were unable to retrieve needed additional or corrected data for two studies.19,20 To allow for comparison of methodologies across articles that did not report an estimate of association, we reported study characteristics alongside the forest plots for visual comparison of methodologies across studies. There were too few studies within each of the outcome categories (any NTDs, or each of the specific NTDs) Environmental Health Perspectives 086002-4 131(8) August 2023

Table 1. Summary of metals and defects assessed, outcome ascertainment methods, study designs, conflicts of interest and funding sources, and risk of bias rankings for included studies.

Reference
Metal(s) assessed Defects evaluated Outcome ascertainmenta Conflict of interest (COI) and fundingb Risk of bias rankings As Cd Pb Mn Hg NTDs Ac Hc Ec SB Hospital/facility Population-based Declared no COI National agencies or
university E O S C M
Liu et al.21
— XX ——
X ————
X
— X X PL PL L PL L
Tian et al.22
— XXX X X ———— — X X X PL PL PL PL L
Tong et al.23 ———— X X XX —— — X X X LLHHLLiu et al.24 ——— X
—
X ————
X
— X X PH L PH H L
Ovayolu et al.25 XXXX X X ————
X
—
X
— L PL L PH PH
Yin et al.26 ———
X
—
X ———— — X X X L PL PH PH L
Demir et al.27 XXXX
—
X ————
X
— X X PH H H H PH
Özel et al.28 XXXX X X ————
X
—
X
— L L PL H L
Troisi et al.29
— XXX X X ————
X
—
X
— PH PL PL H L
Wang et al.30
X ——— — XX —— XX
— X X PL PH PH PL L
Cim et al.31
— XXX
—
X ————
X —— — PL PL PH H L
Marie et al.32,c X ——— —
X ———— — X X X PH L PH PL L
Yan et al.20 ———
X
— XX
— XX X
—
X
— PL H H PH PH
Jin et al.33 ———— X XX ——
X
—
X
— X PH PL U H U
Manduca et al.34
— XX
— XX ————
X
—
X
— PL PL PH H L
Sanders et al.35,d XXXX — — ———
X
— X X X PL L L PL L
Jin et al.19 XXX
— X XX ——
X
— X X X L L H PL L
Liu et al.36 ———
X
— XX —— XX —— X L U U PL U
Ramírez-Altamirano et al.37 —— XX
—
X ————
X
—
X
— L PH H H L
Gatti et al.38,c ——
X ——
X ————
X —— X L PL H H L
Zeyrek et al.39 ——
X ——
X ————
X
—
X
— PL U U H L
Friel et al.40
—
X ——— —
X ———
X —— X PL PL H H L
Carrillo-Ponce et al.41
— XX ——
X ———— — — — — PH U U U U
Cengiz et al.42 ——
X ——
X ————
X —— — PL L PL H L
Macdonell et al.43,c ——
X ——
X ———— —
X —— H PL PH H L
Dawson et al.44 ——
X ——
X ————
X —— — PL L PH H L
Stoll et al.45 ———
X ———
X
—
X
—
X
— X PL PL L H L
Romero et al.46 ——
X
—
X
—
X ———
X —— — PL L H H L
Bound et al.47 ——
X —— XX —— XX —— — PH PH H PL U
Tahan et al.48 ——
X
—
X — ————
X —— — PH L PH H U
Note: As noted in the text, hydrocephaly, although not usually considered to be an NTD, was included in this review because two papers included it and we wanted to be as comprehensive as possible. For additional information on the studycountry, sample size, and exposure assessment, see Figures 2–6. —, not applicable; Ac, anencephaly; As, arsenic; C, confounding; Cd, cadmium; E, exposure assessment; Ec, encephalocele; H, high risk of bias; Hc, hydrocephaly; Hg, mercury;L, low risk of bias; M, missing data; Mn, manganese; NTD, neural tube defect (grouping of ≥2 individual NTDs); O, outcome ascertainment; Pb, lead; PH, probably high risk of bias; PL, probably low risk of bias; S, selection; SB, spina bifida; U, unclear risk of bias.
aThe following definitions were used for categorizing the outcome assessment methods: a) population-based active surveillance: abstractor actively reviews multiple data sources to identify all cases, b) population-based registry (e.g., birth records or passive surveillance): case ascertainment from medical record abstraction or based on registry data only, c) hospital/facility based: based on ≥1 hospital/facility, (a) and (b) are combined in this table as “population-based.” bOnly entries with an “X” have a section in the published manuscript describing conflicts of interest/funding sources, of lack thereof. cAll studies are case–control studies unless indicated by a superscript c. dReferred to as “semi-ecologic” in paper, described herein as a retrospective cohort with ecologic exposure assessment.

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to formally assess heterogeneity in study effect estimates via methods like meta-regression. However, various orderings of the forest plots (e.g., by exposure assessment, which we felt to be the most salient domain by which study quality varied), did not produce discernible patterns.

Quality of Body of Evidence
We assessed the quality of the evidence across all included articles for each metal (Table 2). The quality <0:66 of the evidence for all metals was downgraded owing to numerous studies with notable risk of bias. Specifically, for all metals at least 50% of studies were ranked as having high risk of bias for confounding and high or probably high risk of bias for selection bias. No body of evidence was downgraded for imprecision because none of them had numerous studies with a sample size of ≤15 cases.

Although we did not formally assess publication bias because of the heterogeneity of studies, based on the other considerations outlined in the review protocol (available in the Supplemental Material, “REVIEW PROTOCOL”), we deemed substantial publication bias to be unlikely for all metals. Specifically, no body of evidence was dominated by early, small studies with negative associations; studies were not uniformly small across any of the bodies of evidence; and a comprehensive search was conducted.

We upgraded the evidence for a large magnitude of effect for Hg and Mn (most studies had effect estimates in the same direction and >1:5) as well as Cd (most studies had effect estimates in the same direction and <0:66). We also upgraded the evidence based on an observed dose response for Hg in three studies,19,22,33 Mn in three studies,22,24,26 Cd in one study,19 and Pb in one study.22 No other upgrade factors were applied. Overall, we assigned the evidence for Cd, Hg, and Mn a high quality rating, Pb a moderate quality rating, and As a low quality rating.

Strength of Body of Evidence
We concluded that none of the metals had a literature supportive of conducting a meta-analysis. Specifically, the literature for all Figure 1. Summary of risk of bias analysis for each domain and for each metal, summarized across all studies. For detailed criteria for classifying studies as “high risk of bias” or “low risk of bias,” see the review protocol (available in the Supplemental Material, “REVIEW PROTOCOL”). “Probably low risk of bias” was assigned when there was insufficient information to fully meet the criteria for “low risk of bias” but there was indirect evidence that suggested the criteria were met. “Probably high risk of bias” was assigned when there was insufficient information to fully meet the criteria for “high risk of bias” but there was indirect evidence that suggested the criteria were met. “Unclear risk of bias” was assigned when there was not enough information in the study to determine the risk of bias.

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metals was such that we could not consider random error as the primary concern. In addition, heterogeneous exposure assessment and outcome assessment methodologies were used across studies.

We concluded that the overall direction of association was positive or, in other words, increasing levels of the metal increased the risk of any NTDs, for Hg, Mn, and Pb. We found that the direction of association was consistently negative for Cd and was null for As. For considering confidence in estimates of association, across the evidence for all metals, we deemed it likely that a hypothetical, well-designed new study that disagrees with the current trend Figure 3. Summary of data extracted from all studies of cadmium exposure and risk of NTDs. For each study, we selected the estimate to plot based on the following prioritization: 1) Dose response: plot quartile estimates, then tertile, then above/below median or other dichotomous split. We plotted continuous estimates in addition if presented, as well as nonlinear dose response. 2) Adjustment: fully adjusted estimates were preferentially plotted. Studies that did not present point estimates are summarized in Table S5. Given the range of scales and media of these measurements, they could not be adequately visually summarized. Under the “OR (95% CI)” column, the squares represent the odds ratio values and the bars represent the 95% confidence intervals. Risk of bias (ROB) rankings are indicated by the color coding in the far right column. ROB rankings can also be found in Table 1. The single asterisk indicates the study was not plotted because the reported OR was outside of the reported 95% CI. The double asterisk indicates that the studies did not present point estimates and, rather, presented comparisons of concentrations between cases and controls and are listed without an OR; summary results from these studies are listed in Table S5. Note: %ile, percentile; bmi, body mass index; C, confounding; CI, confidence interval; E, exposure measurement; edu, maternal education; fa, folic acid use; flufev, flu or fever during pregnancy; ga, gestational age; hxBD, history of birth defect; M, missing data; ma, maternal age; Med, median; n/a, not available; NTD, neural tube defect; O, outcome measurement; occup, occupation or employment; OR, odds ratio; pass smoke, passive smoking; raceeth, maternal race or ethnicity; S, selection; sex, infant sex; T, tertile.

Figure 2. Summary of data extracted from all studies of arsenic exposure and risk of NTDs. For each study, we selected the estimate to plot based on the following prioritization: 1) Dose response: plot quartile estimates, then tertile, then above/below median or other dichotomous split. We plotted continuous estimates in addition if presented, as well as nonlinear dose response. 2) Adjustment: fully adjusted estimates were preferentially plotted. Studies that did not present point estimates are summarized in Table S5. Given the range of scales and media of these measurements, they could not be adequately visually summarized. Under the “OR (95% CI)” column, the squares represent the odds ratio values and the bars represent the 95% confidence intervals. Risk of bias (ROB) rankings are indicated by the color coding in the far right column. ROB rankings can also be found in Table 1. The single asterisk indicates studies that did not present point estimates and rather presented comparisons of concentrations between cases and controls are listed without an OR; summary results from these studies are listed in Table S5. The double asterisk indicates that the article provided the N for the full study cohort but only the male-stratified effect estimate. Note: %ile, percentile; C, confounding; CI, confidence interval; E, exposure measurement; edu, maternal education; fa, folic acid use; flufev, flu or fever during pregnancy; geosize, size of municipality; hxBD, history of birth defect; M, missing data; ma, maternal age; Med, median; NTD, neural tube defect; O, outcome measurement; occup, occupation or employment; OR, odds ratio; par, parity; pass smoke, passive smoking; Q, quartile; raceeth, maternal race or ethnicity; S, selection; yr, year of birth.

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would shift our assessment of the quality of the literature. For considering the strength of the evidence for Cd, whereas a high quality rating was given based on the review protocol, our confidence in the upgrade of the evidence for the dose response was weakened, compared with for Hg and Mn, given that the dose response was observed only in one study and was not consistent across studies.

Taken together, we concluded that the current epidemiologic literature provides inadequate evidence for an association of exposure to As, Cd, or Pb with NTD prevalence. We determined that the current body of literature provides a limited evidence base for an adverse association of prenatal exposure to Hg or Mn on NTD prevalence. It is worth noting that studies on Hg included those assessing total Hg, and one specifically evaluating methyl-Hg (MeHg),33 generally considered to be more toxic.49 Total Hg includes inorganic Hg and MeHg, and can act as a good biomarker for MeHg in populations with high fish consumption. However, only two studies that assessed total Hg noted that the population was not a fish-consuming population19,23; therefore, it was difficult to distinguish the effects of MeHg vs. inorganic Hg from the literature currently.

Literature on Metal Mixtures
There was only one included study that assessed the effect of exposure to metal mixtures and risk of NTDs.24 That study evaluated essential metals, including only Mn in its mixture among the metals of interest in this review. Thus, no included study evaluated mixture effects among As, Cd, Hg, Mn, or Pb.

Discussion
Many regulatory agencies, including the U.S. Food and Drug Administration (FDA),50 the U.S. Environmental Protection Agency (EPA),51 the National Institute of Environmental Health Sciences,52 the World Health Organization,53 and the International Agency for Research on Cancer54 make use of systematic reviews of epidemiologic studies to evaluate the safety of chemical exposures within the framework of regulatory decision-making. Because regulatory actions may stem from systematic reviews, it is important that robust approaches be applied to such studies, including prespecification of and transparency in methodology as well as bias identification and possible reduction. With regulatory consequences in mind, we adapted the Navigation Guide methodology, a systematic review approach for use in observational environmental health research, and summarized 30 epidemiologic studies of As, Cd, Hg, Mn, and Pb and NTDs.15,16 There were two major findings. First, we determined that there was limited evidence of an adverse association between Hg or Mn exposure during pregnancy and prevalence of NTDs. Second, we concluded that there was inadequate evidence to assess a relationship between prenatal exposure to As, Cd, or Pb and prevalence of NTDs, thus highlighting the need for additional high-quality studies to make any regulatory decision based on the risk of NTDs upon As, Cd, or Pb exposure.

Our conclusion of limited evidence of an adverse association for prenatal Hg and Mn exposures during pregnancy and prevalence of NTDs reflects consistently positive associations observed across the current bodies of evidence for these metals, which were each deemed high quality. This denoting implies that we believe the evidence suggests there is an effect, but this judgment of the evidence could be convincingly overturned by contradictory, highquality studies. These bodies of literature consisted of four (Hg)19,22,23,33 to six (Mn)20,22,24,26,28,36 case–control studies using biomarker-based exposure assessment, the majority of which reported large magnitudes of adverse associations. In addition, for both Hg and Mn, three studies demonstrated monotonic dose Figure 4. Summary of data extracted from all studies of mercury exposure and risk of NTDs. For each study, we selected the estimate to plot based on the following prioritization: 1) Dose response: plot quartile estimates, then tertile, then above/below median or other dichotomous split. We plotted continuous estimates in addition if presented, as well as nonlinear dose response. 2) Adjustment: fully adjusted estimates were preferentially plotted. Studies that did not present point estimates are summarized in Table S5. Given the range of scales and media of these measurements, they could not be adequately visually summarized. Under the “OR (95% CI)” column, the squares represent the odds ratio values and the bars represent the 95% confidence intervals. Risk of bias (ROB) rankings are indicated by the color coding in the far right column. ROB rankings can also be found in Table 1. Note: bmi, body mass index; C, confounding; CI, confidence interval; E, exposure measurement; edu, maternal education; fa, folic acid use; flufev, flu or fever during pregnancy; ga, gestational age; hxBD, history of birth defect; M, missing data; ma, maternal age; Med, median; n/a, not available; NTD, neural tube defect; O, outcome measurement; OR, odds ratio; pass smoke, passive smoking; S, selection; sex, infant sex; T, tertile.

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responses.19,22,24,26,33 There was particularly strong agreement across high-quality studies of Hg measured in placenta19,23,33 and Mn biomarkers other than hair,22,24,26 although all these studies were limited to exposure assessment at birth, which may not accurately capture early pregnancy exposure, the period of most concern for NTDs.55,56 Further and Mn on NTDs. In addition, assessments of effect measure modification are needed to assist with identifying population subgroups that are most vulnerable to these metals during pregnancy.

A special consideration is needed in interpreting findings for Hg given that most studies measured total Hg, which includes exposure to inorganic Hg (e.g., dental amalgams and preservatives) that do not cross the placenta as easily as MeHg.33,57 Further, all our reviewed Hg studies were based in China, where placental Hg is generally higher than that in other countries,58 so internationally relevant low-dose studies should be conducted to assess toxicity at current levels elsewhere. Regardless, we did note consistent, positive associations in the majority of studies assessing prenatal Hg and NTD prevalence. Putting this finding in the context of regulatory action, the FDA and the U.S. EPA issued joint statements on Hg in 2004 and 2019, detailing fish consumption guidelines based on MeHg exposure in the context of in utero exposure and neurodevelopment risk.59,60 The statement encourages women who are or might become pregnant, breastfeeding mothers, and young children to limit fish consumption to no more than 12 oz (340 g) of commercially caught fish per week and no more than 6 oz (170 g) of locally caught fish per week.59,60 Even though the evidence of an adverse association between prenatal Hg exposure and NTDs observed in this review is limited, it adds to knowledge of the prenatal neurotoxic potential of this metal and thus further emphasizes the need to avoid exposures as advised by the FDA and U.S. EPA.

One notable challenge for regulatory decision-making is that most chemical exposures do not occur in isolation. The Agency for Toxic Substances and Disease Registry (ATSDR) has identified the following priority mixtures: As, Cd, Cr, and Pb, as well as chlorpyrifos, Pb, Hg, and MeHg.61 Notably, even marginal evidence for single metal association with NTDs, as reported herein for Hg and Mn, could be highly relevant if synergistic effects occur in the presence of exposure to these common mixtures, or such evidence may be relevant without synergism in the case where small independent effects of multiple exposures can additively lead to larger joint effects. However, to date, the literature evaluating metal mixture effects on NTDs is extremely limited.

For all other metals examined (As, Cd, and Pb), the literature was deemed inadequate to determine the association with NTDs.

This classification means that the literature is insufficient to assess the effect of the exposure, and that more high-quality studies are needed for any determination. The major area of concern generated from our assessment of the strength and quality of the literature was confounding bias. Notably, many studies included in this review adjusted for no confounders, and among those that did adjust for confounders, no study explained their approach to selection of confounders. This was especially true for studies that evaluated Pb: 12 (60%) of the 20 included studies simply presented a comparison of median or mean concentrations in cases or controls with accompanying t-tests or equivalents.

Figure 5. Summary of data extracted from all studies of manganese exposure and risk of NTDs. For each study, we selected the estimate to plot based on the following prioritization: 1) Dose response: plot quartile estimates, then tertile, then above/below median or other dichotomous split. We plotted continuous estimates in addition if presented, as well as nonlinear dose response. 2) Adjustment: fully adjusted estimates were preferentially plotted. Studies that did not present point estimates are summarized in Table S5. Given the range of scales and media of these measurements, they could not be adequately visually summarized. Under the “OR (95% CI)” column, the squares represent the odds ratio values and the bars represent the 95% confidence intervals. Risk of bias (ROB) rankings are indicated by the color coding in the far right column. ROB rankings can also be found in Table 1. The single asterisk indicates the study had Q3 vs. Q1 OR listed as 0.14 (0.02–1.18) and is not plotted given that this is likely an error. The double asterisk indicates that the studies did not present point estimates and, rather, presented comparisons of concentrations between cases and controls and are listed without an OR; summary results from these studies are listed in Table S5. Note: %ile, percentile; bmi, body mass index; C, confounding; CI, confidence interval; E, exposure measurement; edu, maternal education; fa, folic acid use; flufev, flu or fever during pregnancy; ga, gestational age; hxBD, history of birth defect; M, missing data; ma, maternal age; NTD, neural tube defect; O, outcome measurement; occup, occupation or employment; OR, odds ratio; par, parity; Q, quartile; raceeth, maternal race or ethnicity; ROC, receiver operating characteristic; S, selection; sex, infant sex; smoke, smoking; T, tertile.

Environmental Health Perspectives 086002-9 131(8) August 2023

Crucially, with respect to metals, environmental measurements and biomarker measurements can differ substantially with respect to potential for confounding bias. In studies with environmental matrix, where exposures are attributed to individuals based on area-level concentrations detected in soil or water samples, a key potential confounder would be exposure sources (e.g., pollution sources) emitting copollutants that may truly be driving an effect. There is also potential confounding by factors that vary geographically along with exposure sources, such as socioeconomic characteristics.62 For instance, it is documented that populations living closer to Superfund sites in the United States are more likely to be low-income and racial minorities, vulnerable also to exposures connected to income inequality and systemic racism that may influence the risk of NTDs as well.63,64 In contrast, when exposure measures derive from biomarker measurements (e.g., maternal urine), the potential for “physiologic confounding” becomes an additional concern, where (sometimes hard-to-capture) factors, such as metabolism, urine dilution, and blood volume, can influence biomarker measurements and reflect underlying physiologic differences that relate to the subsequent risk of a NTD, such as diabetes status and nutritional status (including folate levels).65 Both biomarker and environmental measures are common in assessing health effects of metals exposure, emphasizing a need to address the potential for confounding differently for these two types of exposure assessment methods.

In addition to confounding bias, we identified selection bias as a major area of concern in the current literature evaluating metals and NTDs. One salient concern in studies of birth outcomes such as NTDs arises when the target population is the population of conceptuses, or very early stage fetuses. Often, studies of birth defects are restricted to live births or pregnancies that progress past some period of gestation (e.g., 20 wk). In such cases, the study population consists of pregnancies that last at least to the minimum gestational age, so that processes occurring prior to that time can lead to informative loss of fetuses from the target population. This phenomenon, which has been termed live birth bias, is illustrated in the directed acyclic graph (DAG) shown in Figure 7.
66,67 In this figure, restricting the study population to fetuses that survive past a certain gestational age, or to birth, means that exposures measured before fetal death can have spurious relationships with NTDs if there are unaccounted for factors (U) that can result in either fetal death or NTDs. This bias can potentially be reduced by analytic approaches to selection bias, such as inverse probability weighting, or by generating different target parameters, such as survivor average causal effects.68,69 However, in many cases U must be known and well measured to do so, or the full population of conceptuses must be enumerated, and these challenges can be substantial. To some extent, all studies examined in this review were subject to potential bias from missing information on early pregnancy losses, although the potential magnitude of this bias is not well understood. Thus, rather than conclude that every study was subject to a high risk of bias for selection bias, we assessed studies relative to what could be feasibly done in studies of birth defects. If exposure to metals does increase the risk of early loss and if other factors also jointly increase both early loss and NTDs, then we would expect this bias to be toward the null such that prevalence ratios and odds ratios would underestimate true risk ratios and cumulative incidence ratios that would have been estimated in the absence of early losses.

The final major area of needed improvement identified was exposure assessment. In general, for all metals, articles included Figure 6. Summary of data extracted from all studies of lead exposure and risk of NTDs. For each study, we selected the estimate to plot based on the following prioritization: 1) Dose response: plot quartile estimates, then tertile, then above/below median or other dichotomous split. We plotted continuous estimates in addition if presented, as well as nonlinear dose response. 2) Adjustment: fully adjusted estimates were preferentially plotted. Studies that did not present point estimates are summarized in Table S5. Given the range of scales and media of these measurements, they could not be adequately visually summarized. Under the “OR (95% CI)” column, the squares represent the odds ratio values and the bars represent the 95% confidence intervals. Risk of bias (ROB) rankings are indicated by the color coding in the far right column. ROB rankings can also be found in Table 1. The single asterisk indicates that the studies did not present point estimates and, rather, presented comparisons of concentrations between cases and controls and are listed without an OR; summary results from these studies are listed in Table S5. The double asterisk indicates the studies provided no confidence limits. Note: %ile, percentile; bmi, body mass index; C, confounding; CI, confidence interval; deprivation, area-level deprivation score; E, exposure measurement; edu, maternal education; fa, folic acid use; flufev, flu or fever during pregnancy; ga, gestational age; M, missing data; ma, maternal age; Med, median; n/a, not available; NTD, neural tube defect; O, outcome measurement; OR, odds ratio; par, parity; raceeth, maternal race or ethnicity; ROC, receiver operating characteristic; S, selection; sex, infant sex; T, tertile.

Environmental Health Perspectives 086002-10 131(8) August 2023

in this review collected samples after the critical window for NTDs, which predominantly develop in the first 4 wk of pregnancy.55,56 It is challenging to capture biomarkers of exposure during this window given that many women do not yet know they are pregnant. Future studies could use maternal toenails as a biomarker of exposure, which are noninvasive, have been shown for As and Mn to be valid biomarkers of maternal–fetal transfer and have the potential to be time stamped to a window of exposure, such as early pregnancy.70–72 In addition, studies could consider the use of children’s teeth, which can also be time stamped, although this would not be feasible for lifelimiting birth defects.73,74 The studies we reviewed also varied in sample collection, preparation, and analytical methods used for biomarker measurements, with some studies failing to provide details on laboratory procedures at all. This is critical because some of the biomarkers used are particularly susceptible to misclassification from sample collection and preparation methods. For example, past studies have shown that Cd concentrations vary throughout the placenta, and the way in which samples are collected and processed has an important impact on results.75 In addition, hair samples can reflect both internal dose and external deposition of metals.

Consistent methods for washing hair samples prior to processing are necessary to ensure externally deposited contaminants are removed.70
Moreover, regardless of laboratory procedures, the matrices used to estimate exposure concentrations in many of the studies reviewed may not be optimal for the specific metals of interest.

For instance, Cd is known to accumulate in the placenta.58,76 Therefore, measured placental concentrations of these metals likely represent cumulative maternal exposures during gestation.

Given that NTD cases have a high risk of preterm birth, the time period for accumulation to occur (i.e., gestation), can be much shorter in cases vs. controls.77 This may lead to placental Cd being lower in cases vs. controls as an artifact of gestational age, rather than this metal truly being protective of NTDs. In the one study included that assessed placental Cd and NTD prevalence, indeed a negative relationship was found for both spina bifida and any NTDs.19 This accumulation of Cd in placenta may represent a bias in exposure assessment that explains the counterintuitive findings finding that Cd demonstrated a negative relationship with NTDs prevalence. This negative relationship was, however, also observed for infant serum collected at birth and census tract well-water concentrations; therefore, it is also possible that the accumulation of Cd in placenta tissue represents a true barrier to fetal exposure, thus protecting it from Cd toxicity.35,41 Overall, Table 2. Summary of quality and strength of evidence for metals and neural tube defects.

Mn Pb Cd Hg As
Quality factor
Downgrade factors
Risk of bias across studies −1 −1 −1 −1 −1
Imprecision 0 0 0 0 0
Publication bias 0 0 0 0 0
Upgrade factors
Large magnitude of effect 1 0 1 1 0
Dose response 1 1 1 1 0
Confounding minimizes effect 0 0 0 0 0
Overall quality of evidence 1 0 1 1 −1
Strength considerations
Quality of body of evidence High Moderate High High Low Direction of effect Increase Increase Decrease Increase Null Confidence in estimates of
association: “Is it likely or
unlikely that a new study
would change the trend/pattern
observed in the high quality
literature at the moment?”
Likely Likely Likely Likely Likely
Other compelling attributes of
the data that may influence
certainty
There are three studies that demonstrate a monotonic
dose response. If
you remove the
study using hair as
the exposure, the
studies are very
consistent.

None Although one
study did
demonstrate a
monotonic
dose response,
this is not consistent across
studies.

There are three
studies that
demonstrate a
monotonic
dose response.

None
Overall strength of evidence
(“sufficient,”“limited,”“inadequate,” or “evidence of lack of effect”)
Limited Inadequate Inadequate Limited Inadequate
Note: decrease, increasing exposure levels/decreasing risk; high, sum of quality factors is ≥1; increase, increasing exposure levels/increasing risk; low, sum of quality factors is ≤− 1; moderate, sum of quality factors is 0.

Figure 7. Directed acyclic graph describing live birth bias in the context of prenatal metal exposure and neural tube defects (NTDs). Note: U, unknown or unaccounted for factor.

Environmental Health Perspectives 086002-11 131(8) August 2023

although a negative relationship was observed for Cd, the strength of the evidence was deemed inadequate to make a formal judgment.

Although outcome assessment was judged to be less of an urgent concern for improving this literature, there are several relevant notes for considerations of future study designs. The articles included in this review varied in their outcome assessment methods. Some relied on a single trained health care worker to visually assess outcomes and identify cases, whereas others involved a team of physicians who reviewed and crossvalidated outcomes, potentially using imaging and laboratory studies to assist with case identification. Many did not provide clear details about the outcome assessment methods, limiting our ability to compare across studies.73,74 Misdiagnosis of lesssevere, nonvisually observable birth defects (e.g., congenital heart defects) is a well-known issue.78–82 This could lead to missed cases of less-severe NTDs, such as spina bifida.

However, several studies have found that most NTDs (e.g., spina bifida, anencephaly, encephalocele), which are severe and easy to see, are less prone to misclassification and diagnostic variability than other birth defects.78,81,82 Thus, although issues related to outcome assessment methods could have led to some misclassification or missed cases, this is less likely with NTDs, and misclassification would not be expected to vary by exposure status.

Despite the use of a transparent and thorough protocol, there are some limitations of this approach. Although we aimed to conduct a comprehensive review of prior literature, it is possible that we did not identify every relevant study. For instance, we did not search the gray literature for possibly relevant studies. For some studies, point estimates or precision measures were not available, and we were not able to obtain this information despite our attempts to contact study authors. We did not conduct a formal meta-analysis of study effect estimates nor a formal assessment of publication bias for any of the metals we assessed owing to the lack of a sufficient number of studies and the heterogeneity of the study methodologies. We did not review toxicologic studies to inform potential biological mechanisms and plausibility of relations under study because we considered this literature to be outside the scope of our review.

Finally, our risk of bias decisions were based on our author team’s knowledge, expertise, and judgments, and it is possible that our conclusions may differ from those of another research team. As an example, there are some other potentially important confounders that could have also been considered in the risk of bias, including maternal obesity and diabetes, as well as folate status; however, we did not consider these based on our DAG analysis. Although not a limitation of this review, per se, it is worthy of note that many other categories of birth defects, including urinary system defects, genital organ defects, and digestive system effects, did not have an adequate number of studies to summarize the literature, thus pointing to literature gaps in need of further research.

Overall, we found that the literature examining relationships between prenatal exposure to As, Cd, Hg, Mn, and Pb and NTDs is sparse and generally in need of higher-quality studies. Future studies can improve the literature substantially by employing robust exposure assessment methods in relevant time windows and consider modern approaches to reducing or controlling confounding and selection bias. Although the overall strength of the evidence was inadequate to decide for other heavy metals, we found limited evidence of an adverse association between prenatal Hg or Mn and NTD prevalence, which speaks to the consistency of the results despite a multitude of potential biases. Overall, owing to limitations of the existing evidence base, the role of prenatal As, Cd, and Pb exposure in etiology of NTDs remains unclear and warrants further investigation in high-quality studies.

Acknowledgments
We thank K. Moon for her guidance in synthesizing the
results and V. Davila for her assistance with data cleaning and organization. We also thank the librarians at the University of North Carolina at Chapel Hill Health Sciences Library for their assistance with conducting the literature search.

This research was supported in part by the National Institutes of Health/National Institute for Environmental Health Sciences (R01ES029531, to A.P.K.; P42ES031007, to R.C.F.).

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82. Langlois PH, Scheuerle A. 2007. Using registry data to suggest which birth defects may be more susceptible to artifactual clusters and trends. Birth Defects Res A Clin Mol Teratol 79(11):798–805, PMID: 17990341, https://doi.org/

10.1002/bdra.20407.

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Outlook
Public Forum Public comment next CC 10/13
From Michelle Covell <[email protected]>
Date Fri 10/9/2026 10:48 AM
To Andrew Bradley <[email protected]>; Public Comment <[email protected]> 1 attachment (611 KB)
manganese-fact-sheet-2022.pdf;
Hi Andrew please find attached pdf for another public comment The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St. Helena or the St. Helena Planning Commission.

Michelle Liu Covell
Resident, Architect

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GUIDELINES FOR DRINKING-WATER QUALITY: FOURTH EDITION
INCORPORATING THE FIRST AND SECOND ADDENDA
and well below the upper limit of the ADI. As the chemical occurs in drinking-water at concentrations much lower than the health-based value, the presence of malathion in drinking-water under usual conditions is unlikely to represent a hazard to human health. For this reason, it is considered unnecessary to derive a formal guideline value for malathion in drinking-water.

Manganese1
Manganese is one of the most abundant metals in Earth’s crust, usually occurring with iron. It can exist in 11 oxidation states, often as chloride, oxides and sulfates. The most common oxidation states for manganese in natural water are manganese(II) and manganese(IV). Manganese is used principally in the manufacture of iron and steel alloys, and manganese compounds such as potassium and sodium permanganate are ingredients in various products used for cleaning, bleaching and disinfection. Manganese compounds are additionally used in some locations for potable water treatment and can also be an impurity in coagulants used during water treatment. Manganese occurs naturally in many surface water and groundwater sources; although naturally occurring manganese is usually the most important source for drinking-water, anthropogenic activities can also contribute to high levels of manganese in water.

Manganese also occurs naturally in many food sources, and the greatest exposure to manganese is usually from food.
1 As naturally occurring manganese in drinking-water is a chemical of concern in many areas, its chemical fact sheet has been expanded.

Provisional guideline value Total manganese: 0.08 mg/l (80 µg/l), to be protective against neurological effects in the most sensitive subpopulation—bottle-fed infants—and consequently the general population
This guideline value is provisional because of the high level of uncertainty, as reflected in the composite uncertainty factor of 1000 Occurrence Levels in fresh waters vary widely. They are typically in the range 1–200 µg/l. Higher levels are usually associated with groundwater, lakes and reservoirs under acidic or reducing conditions, or in aerobic waters with industrial pollution. Very high concentrations (up to 10 mg/l) have been reported in acidic groundwater. In treated drinking-water, concentrations are typically less than 50 µg/l.

TDI 0.025 mg/kg bw, derived by applying an uncertainty factor of 1000 to a LOAEL of 25 mg/kg bw per day identified from studies that reported neurological effects in rats exposed to manganese from birth to postnatal day 21. The uncertainty factor takes into account interpecies variation (10), intraspecies variation (10) and database uncertainties (10, including use of a LOAEL).

Limit of detection 0.002 µg/l by ICP-MS; 0.005–50 µg/l by ICP-AES and GFAA spectrometry; and 10–70 µg/l by colorimetric methods. None of these methods distinguish between the different oxidation states of manganese.

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12. CHEMICAL FACT SHEETS
Treatment performance Manganese concentrations in drinking-water can be easily lowered to less than 0.05 mg/l using several treatment methods, including oxidation/filtration, adsorption/oxidation, softening/ion exchange and biological filtration. Selection of the appropriate treatment system for manganese removal depends on the form of manganese (dissolved or particulate) in the source water.

Guideline value derivation
• allocation to water
• weight
• consumption
50% of TDI
5 kg body weight for a bottle-fed infant

0.75 litres per day for a bottle-fed infant
Additional comments Risks to infants arising from exceedance of the provisional guideline value may be mitigated by following the WHO recommendation for exclusive breastfeeding, or by using an alternative safe source of drinking-water (e.g. bottled water that is certified by the responsible authorities) to prepare formula.

The presence of particulate manganese in drinking-water systems can cause acceptability problems; concentrations above 0.02 mg/l have caused complaints about discoloured water and staining of plumbing fixtures and laundry. Therefore, aesthetic as well as health aspects should be considered in the management of manganese in drinkingwater, and when setting regulations and standards for drinking-water quality.

Assessment date 2020
Principal references WHO (2021) Manganese in drinking-water Manganese is an essential trace element. It is a necessary component of a number of enzymes and activates several others. The central nervous system is the primary concern for manganese toxicity in mammals, including humans. Neurodevelopmental toxicity studies in manganese-exposed juvenile rats revealed behavioural and sensorimotor effects, and corresponding neurostructural and neurochemical changes.

Several epidemiological studies have also reported neurological effects (including reduced cognitive ability) in adult populations and children following ingestion of manganese-contaminated water. The epidemiological studies have limited utility in risk assessment due to uncertain manganese exposure levels, unclear temporality of effects and other potential confounding factors. However, collectively, they provide qualitative support that the neurological effects reported in animal studies are relevant in humans. Existing studies and reports do not provide adequate evidence to assess potential carcinogenicity from oral exposure to manganese in humans.

Absorption of manganese from the gastrointestinal (GI) tract has been suggested to take place through both an active transport mechanism and passive diffusion. GI absorption is influenced by several factors, including dietary factors: absorption is negatively correlated with intake of dietary fibre, oxalic acids and phytic acids. Some studies and reports have suggested that absorption and bioavailability of manganese are greater from drinking-water than from food, although other studies have reported no differences. However, absorption from drinking-water may be influenced by fasting conditions and the chemical form of manganese.

422
GUIDELINES FOR DRINKING-WATER QUALITY: FOURTH EDITION
INCORPORATING THE FIRST AND SECOND ADDENDA
Following GI tract absorption, manganese is distributed via the systemic circulation to all tissues. Levels of manganese can increase in several tissues following oral exposure, including some regions of the brain in infants and adults. The main route of elimination of manganese from the body is faecal elimination via hepatobiliary excretion.

Manganese absorption from the GI tract may be higher in infants than in adults.

Infants also retain higher levels of manganese than adults during the early neonatal period, possibly because of the incomplete development of the biliary excretion system. Along with the important neurodevelopmental processes occurring in neonates, this may render them particularly susceptible to toxicity from exposure to manganese. Further, there is potential for increased exposure to manganese in bottle-fed infants compared with breastfed infants—from the concentrated or powdered formula itself as well as the tap water used to prepare the formula.

Practical considerations
Manganese levels in drinking-water can be an issue in both high- and low-income countries, and should be considered in establishing national standards and local guidance. Resource-limited suppliers, in particular, may have difficulty in achieving the provisional guideline value; in such cases, incremental improvements towards meeting the provisional guideline value are encouraged. This is a particular problem for groundwater, for which treatment may be minimal and prohibitively expensive. In such instances, benefits from a reliable, microbiologically safe groundwater source should be assessed against the risks posed by an alternative source that may be subject to faecal contamination. Issues of acceptability of the drinking-water (which varies between different populations) should also be considered, since reduced acceptability may lead consumers to turn to more aesthetically acceptable but less microbiologically safe water supplies. It is vital that a sufficient supply of acceptable, microbiologically safe water is always available, even if some guidelines or standards for chemicals such as manganese cannot be immediately met.

Manganese should be evaluated and managed in the context of developing a WSP (see chapter 4). Surface waters prone to high and variable concentrations of manganese may require more frequent and targeted monitoring than groundwater.

Where manganese is present at concentrations close to the provisional guideline value or the water is treated to remove manganese, routine monitoring should be conducted after treatment. If manganese is detected at the point of collection or use, or aesthetic issues related to manganese are reported by consumers, this indicates that treatment for manganese removal is not optimized or that the distribution system is not appropriately managed.

Options for controlling levels in groundwater include drilling a new well or blending water from different wells. For lake and reservoir sources where there is a thermocline and lower water levels become anoxic, management of the sources to prevent release of manganese from sediment is important.

Selection of the appropriate treatment system for manganese removal depends on the form of manganese (dissolved or particulate) in the source water. Dissolved manganese(II) is most often the predominant form present in anoxic and acidic

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12. CHEMICAL FACT SHEETS
groundwater or lakes. However, depending on the pH and the dissolved oxygen content of the water, a combination of dissolved and particulate manganese can be present. In general, treatment methods used for manganese rely on a combination of processes (e.g. oxidation, adsorption, filtration) to remove both the dissolved and particulate forms. At the point of use, reverse osmosis is the most effective and reliable treatment technology; however, point-of-use units using ion exchange media are also moderately effective. To reduce water discoloration and staining of laundry and fixtures, ion exchange and greensand filtration with careful operation and maintenance can be used at the point of entry.

Low levels of manganese in source or treated water can accumulate in the distribution system. Periodic release of manganese can then occur, resulting in high levels at the tap. Releases can occur as a result of physical or hydraulic disturbances to the system (e.g. mains breaks, hydrant flushing) or changes in water chemistry (e.g. changes in pH, temperature, chlorine residual, source water type/blending). Physical and hydraulic disturbances most often release particulate manganese and can cause discoloured water and consumer complaints. Chemical releases can go unnoticed if manganese occurs predominantly in the dissolved form. Other contaminants (e.g. arsenic, barium, chromium, lead, uranium) that deposit with manganese oxides in the distribution system may also be released into the water and reach consumers’ taps. Control measures to minimize manganese release events include maintaining stable water chemistry and minimizing manganese levels entering the distribution system, the amount of manganese oxide deposits in the distribution system (through best practices for water mains cleaning), and physical or hydraulic disturbances.

MCPA
MCPA is a phenoxyacetic acid herbicide that is found in various formulations: as the free acid (CAS No. 94-74-6), as a dimethylamine salt (CAS No. 2039-46-5), as a sodium salt (CAS No. 3653-48-3) and as a 2-ethylhexyl ester (CAS No. 29450-45‑1).

It is a post-emergence herbicide that is widely used against broadleaf weeds in agriculture and horticulture and on grassland and lawns. All forms of MCPA will dissociate in water to the acid (anion) form. MCPA is highly soluble in water. Biological degradation is an important process in determining MCPA’s environmental fate. Chlorophenols and chlorocresols are potential soil metabolites and may, if present in water, give rise to unacceptable tastes. Surface water may be contaminated via spray drift and runoff, whereas groundwater may be contaminated via leaching from soil. Exposure from food is likely to be low.

Reason for not establishing
a guideline value
Occurs in drinking-water or drinking-water sources at concentrations well below those of health concern
Health-based value* 0.7 mg/l
Acute health-based value** 20 mg/l
Occurrence Concentrations in surface water usually less than 1 µg/l; concentrations in drinking-water usually below 0.1 µg/l

Outlook
Public Comment CC 10/13/26
From Michelle Covell <[email protected]>
Date Fri 10/9/2026 10:56 AM
To Andrew Bradley <[email protected]>; Public Comment <[email protected]> 1 attachment (894 KB)
manganese-nl-rl-technical-memo-20220406.pdf;
Andrew, please find attached pdf for public comment.

Thank you,
The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St. Helena or the St. Helena Planning Commission.

Michelle Liu Covell
Resident, Architect

State Water Resources Control Board
TO: Darrin Polhemus
Deputy Director, Division of Drinking Water
State Water Resources Control Board
FROM: Eric Miguelino, M.D.

Research Scientist IV

DIVISION OF DRINKING WATER
DATE: April 7, 2022
SUBJECT: RECOMMENDATION FOR REVISED NOTIFICATION AND RESPONSE

LEVELS FOR MANGANESE
______________________________________________________________________ Request
Based on the potential risk for manganese-induced neurotoxicogical effects to bottle-fed infants, the Division of Drinking Water (DDW) scientific staff recommends revising the notification and response levels for manganese, which are currently set at 500 µg/L and 5,000 µg/L, respectively. For comparison purposes, the secondary maximum contaminant level for manganese is 50 µg/L.

DDW requests for the Office of Environmental Health Hazard Assessment (OEHHA) to review and comment on the following derivation of a manganese health protective concentration (HPC) of 20 µg/L. The health protective concentration would serve as the basis for future recommended revisions to the current notification and response levels.

Background
Manganese is the 12th most abundant element and composes approximately 0.1% of the earth’s crust, which makes it ubiquitous in the environment (Martinez-Finley et al., 2012). It can naturally occur in both surface water and groundwater sources.

Manganese is an essential nutrient and enzyme cofactor that is naturally present in many foods and available as a dietary supplement, but despite its nutritional benefits, adverse health effects can be caused by over-exposure. There is substantial evidence that demonstrates that exposure to manganese at high levels can pose a neurotoxic risk (ATSDR, 2012; US EPA, 2004; WHO, 2004). Occupational manganese exposure has

Darrin Polhemus, Deputy Director - 2 - April 7, 2022
been shown to cause a distinct neurologic condition known as manganism, a clinical syndrome of cognitive dysfunction that resembles Parkinson disease (Andruska et al., 2015).

The main route of manganese absorption is through the gastrointestinal tract, but absorption also occurs in the lungs following inhalation exposure (O’Neal, 2015).

Clinically significant cases due to inhalation are mainly associated with occupational exposures (O’Neal, 2015). There is little evidence that dermal contact with manganese results in significant absorption through the skin and dermal contact is not generally viewed as an important source of exposure (ATSDR, 2012).

Children are considered to be particularly susceptible to possible effects of high levels of manganese exposure because they absorb and/or retain more manganese than adults (ATSDR, 2012). Overexposure to manganese can adversely affect child neurodevelopment (Collipp et al.,1983; Tran et al., 2002; Wasserman et al., 2006; Claus Henn et al., 2010, Bouchard et al., 2011).

Recognizing the vulnerability of children to manganese, some regulating agencies have developed more restrictive guidance or standards to address the potential health risk for infants who may be exposed to elevated levels of manganese in drinking water. For example, Minnesota’s Department of Health has a 100 µg/L guidance level, based on the study of Kern, et al., (2010) and Health Canada has a maximum allowable concentration of 120 µg/L.

In view of research findings that show the susceptibility of the developing nervous system to elevated levels of manganese, it is clear that the current notification level of 500 µg/L and response level of 5,000 µg/L should be revised downward, in order to provide a more protective health-based guidance. Such a change is further supported by recent revisions of drinking water advisories and standards for manganese by other regulating agencies outside of California.

Summary of Pertinent Research
Animal Data
In 2006, OEHHA developed a technical document recommending a child-specific reference dose (chRD) for manganese for its school site risk assessment. OEHHA reviewed both human data (see below) and animal data. OEHHA evaluated two neurotoxicological studies on neonatal rats:
· Dorman et al. (2000) evaluated the relative sensitivity of neonatal rats after the administration of 0, 25, or 50 milligrams (mg) manganese chloride/kilogram (kg)-day (0, 11, or 22 mg manganese/kg-day derived by OEHHA) over 21 postnatal days. The study concluded from startle response data that neonates may be at greater risk for manganese-induced neurotoxicity from a dose of 11 mg manganese/kg-day.

Darrin Polhemus, Deputy Director - 3 - April 7, 2022
· Tran et al. (2002) analyzed the potential neurological effect of manganese supplements on neonatal rats after the administration of 0, 50, 250, or 500 mg manganese chloride/kg-day (0, 1.6, 8.3, or 16.7 mg manganese/kg-day derived by OEHHA) over 21 postnatal days. The study concluded that at 8.3 mg manganese/kg-day, adverse effects were seen in the homing test, and at

1.6 mg manganese /kg-day, adverse effects were seen in the passive avoidance test.

Kern et al. (2010) studied the relationship between early manganese exposure and neurobehavioral deficits. The authors administered oral doses of manganese to neonatal rats at levels of 0, 25, or 50 mg/kg/day over 21 postnatal days. Kern then evaluated the rats’ performance in behavioral tests, and measured levels of chemicals in areas of the rat brains. Specifically, the behavioral tests were open arena, elevated plus maze, and 8- arm radial maze. The chemicals evaluated were levels of dopamine D1 and D2 receptor proteins, as well as the dopamine transporter (DAT), which were measured in the prefrontal cortex, nucleus accumbens, and dorsal striatum. For the neonates receiving the 50 mg/kg/day dose, the authors observed altered locomotor activity and behavioral disinhibition in the open area test, altered learning and increased number of errors in the radial maze, and impaired learning/memory in the 8-arm radial test. For the neonates receiving the 25 mg/kg/day dose, Kern observed impaired learning/memory in the 8-arm radial test and reported a reduced level of D1 receptor levels in the dorsal striatum.

Beaudin et al. (2017) studied whether early postnatal oral manganese exposure causes lasting attentional and impulse control deficits in adulthoods and whether lifelong exposure could exacerbate those effects. Neonatal rats were exposed to manganese orally with 0, 25, or 50 mg/kg/day over 21 postnatal days, and then were subjected to a series of learning and attention tasks, using the five-choice serial reaction time task. The study demonstrated that early postnatal manganese exposure caused lasting attentional dysfunction due to impairments in attentional preparedness, selective attention, and arousal regulation. Specifically, manganese exposure impaired performance in the focused attention task, but the dysfunction was limited to the early postnatal (postnatal days 1-21) 25 mg/kg/day group and lifelong 50 mg/kg/day group.

Human Data
In 2006, OEHHA recommended a chRD of 0.03 mg/kg-day for manganese for its school site risk assessment. This recommendation was based on human data, specifically the daily manganese intake upper limit (UL) of 11 mg/L for which there were no observed adverse effects in adults (Food and Nutrition Board, 2002). OEHHA derived the chRD by adjusting for background source contributions of manganese and applied an uncertainty factor of 3 to account for differences between children and adults in GI absorption, biliary excretion, blood-brain barrier, and transferrin receptors (OEHHA, 2006).

Additional Data Conclusions
OEHHA’s chRD of 0.03 mg/kg-day for manganese was considered in the development of the notification level but was determined to provide less health protection for infants than

Darrin Polhemus, Deputy Director - 4 - April 7, 2022
the health protective concentration (HPC) calculated by DDW staff. Given the potential increased sensitivity of the developing infant to neurological toxicity, DDW staff would have used an uncertainty factor of 10 rather than a value of 3 [which was used in the OEHHA (2006) document for school site risk assessments]. This change accounts for differences in infants versus adults, in order to provide more appropriate public health protection for the very young. Thus, because of the difference in uncertainty factors, the chRD was not considered further.

OEHHA (2006) noted that its calculated values were in a narrow range, and that its child reference dose of 0.03 mg/kg-day based on humans was comparable to the value of

0.035 mg/kg-day, a value derived from averaging all the calculated values from the animal data. In addition, the reasoning behind calculating an equivalent manganese content from manganese chloride was not discussed. Nevertheless, OEHHA did not use the cited animal data to develop the chRD. DDW staff considered using these data in developing the notification level, but ultimately decided to use the more recent study by Kern et al., (2010) in this process.

Calculation of Health Protective Concentration for the Notification Level To derive the HPC for manganese, DDW staff made use of HPC calculations that OEHHA uses in its recommendations for notification levels in drinking water and for its established public health goals.

Calculations of HPCs involve determination of the point of departure (POD) from the dose-response data, and an estimation of an acceptable daily dose (ADD), as described below:
· POD is a dose of a chemical from a study in animals or humans that is used as a starting point for calculation of the ADD. It is a statistical determination that identifies a point at which exposure levels that result in no toxicological response among test subjects deviate to exposures that do result in a toxicological response. With adequate data, statistical benchmark dose (BMD) modelling can be used. When data are not amenable to BMD modeling, a no observed adverse effect level (NOAEL) or a lowest observed adverse effect level (LOAEL) may serve as the POD. Kern et al. (2010) reported a reduced level of D1 receptor levels in the dorsal striatum and impaired learning/memory for neonate rats at the LOAEL of 25 mg/kg-day.
· ADD is an estimated maximum daily dose (expressed as mg/kg-day) of a chemical that can be consumed by humans for an entire lifetime without toxic effects. To determine the ADD, the POD is adjusted by uncertainty factors (UFs).
· UFs are used in noncancer risk assessments to account for uncertainties in data that provide the basis for the risk estimate. These include the availability of data (LOAEL vs. NOAEL), differences between animals and humans (interspecies extrapolation), and differences among humans (intraspecies variation, including sensitive subgroups) in response to a chemical exposure. OEHHA (2008) has

Darrin Polhemus, Deputy Director - 5 - April 7, 2022
established possible default uncertainty factors for reference exposure levels.

DDW has applied a combined UF of 1,000:10 for the use of a LOAEL in the absence of a NOAEL; 10 for interspecies extrapolation, consisting of √10 for pharmacodynamics and √10 for pharmacokinetics; and 10 for intraspecies variability, consisting of √10 for pharmacodynamics and √10 for pharmacokinetics, which accounts for variability within the human population, e.g., for children vs. adults.

ADD = POD ÷ UF
ADD = 25 mg/kg-day ÷ 1000
ADD = 0.025 mg/kg-day
According to the current dietary guidelines for infants (American Academy of Pediatrics, 2020), infants are expected to be exclusively fed human milk or iron-fortified infant formula. At approximately six months of age nutrient-dense complementary foods are introduced to the infant diet. Therefore, DDW used this guidance to justify both the relative source contribution (RSC) and the daily water intake (DWI) of the affected population.
· RSC is the proportion of exposures to a chemical attributed to drinking water. and typically ranges from 20 to 80 percent (expressed as 0.20 to 0.80). In the absence of complete data, the estimated RSC involves a large component of “professional judgment.” (OEHHA, 2004).

There are several factors that were considered for the selection of an appropriate RSC. Since infants have been identified as the susceptible population, the amount of manganese expected to come from infant formula was considered. Frisbie, et al. (2019) measured manganese levels in 25 infant formula products from the United States, and found an average of 650 µg/L and median value of 400 µg/L.

In addition, California has an enforceable drinking water standard, secondary maximum contaminant level (SMCL) of 50 µg/L. Lastly, the required daily intake for infants under the age of 6 months was considered. According to the Institute of Medicine (US) Panel on Micronutrients (2001), the recommended adequate intake of manganese for children under the age of 6 months is 3 µg/L and reflects the observed mean manganese intake of infants principally fed human milk. Based on the manganese fortification in the infant formulas, intake was determined to be in excess from each source contribution.

It is expected that infants under the age of 6 months are almost exclusively fed with liquid versus solid food, and formulas are typically mixed at a 1:1 ratio.

Therefore, for such infants, ingestion of manganese in drinking water (say, at concentrations below the 50 µg/L SMCL) is considerably lower than that coming from infant formula on the average, as mentioned above, by at least a couple of orders of magnitude. Given the dietary contribution of manganese from sources other drinking water, DDW staff used an RSC of 0.2.

Darrin Polhemus, Deputy Director - 6 - April 7, 2022
· DWI is expressed in units of liters per kilogram of body weight per day (L/kg-day).

OEHHA’s derivation of drinking water public health goals (PHGs) uses agespecific and normalized-to-body-weight water ingestion estimates (OEHHA, 2012). DDW selected the 95th percentile consumer-only water intake rate of

0.237 L/kg-day for infants 0-6 months of age for the notification level derivation.

Use of the 0- to 6-month infant drinking water intake rate is consistent with OEHHA’s approach for two other drinking water toxicants, namely, perchlorate (OEHHA, 2015) and perfluorobutane sulfonic acid (OEHHA, 2021). · HPC is derived by multiplying the ADD by the relative source contribution (RSC) and dividing by the daily water intake (DWI) of the affected population.

HPC = ADD X RSC ÷ DWI
HPC = 0.025 mg/kg-day X 0.2 ÷ 0.237 L/kg-day
HPC = 0.021 mg/L (or 21 µg/L, rounded to 20 µg/L)
Cited References
American Academy of Pediatrics (2020). Nutritional needs of infants, toddlers part of new Dietary Guidelines. AAP Publications: AAP News.
https://publications.aap.org/aapnews/news/12374
Andruska KM, Racette AB. Neuromythology of Manganism. Curr Epidemiol Rep. 2015 Jun;2(2):143-148. doi: 10.1007/s40471-015-0040-x. PMID: 26046010; PMCID:

PMC4450773.

Agency for Toxic Substances and Disease Registry (ATSDR). (2012). Toxicological Profile for Manganese. Retrieved from http://www.atsdr.cdc.gov/toxprofiles/tp151.pdf Beaudin SA, Strupp BJ, Strawderman M, Smith DR. Early Postnatal Manganese Exposure Causes Lasting Impairment of Selective and Focused Attention and Arousal Regulation in Adult Rats. Environ Health Perspect. 2017 Feb;125(2):230-237. doi:

10.1289/EHP258. Epub 2016 Jul 6. PMID: 27384154; PMCID: PMC5289906. https://ehp.niehs.nih.gov/doi/pdf/10.1289/EHP258
Bouchard MF, Sauvé S, Barbeau B, Legrand M, Brodeur MÈ, Bouffard T, Limoges E, Bellinger DC, Mergler D. Intellectual impairment in school-age children exposed to manganese from drinking water. Environ Health Perspect. 2011 Jan;119(1):138-43. doi:

10.1289/ehp.1002321. Epub 2010 Sep 20. PMID: 20855239; PMCID: PMC3018493.

Claus Henn, B., Ettinger, A. S., Schwartz, J., Tellez-Rojo, M. M., Lamadrid-Figueroa, H., Hernandez-Avila, M., Wright, R. O. (2010). Early postnatal blood manganese levels and children's neurodevelopment. Epidemiology, 21(4), 433-439.

Darrin Polhemus, Deputy Director - 7 - April 7, 2022
Collipp, P. J., Chen, S. Y., Maitinsky, S. (1983). Manganese in infant formulas and learning disability. Ann Nutr Metab, 27(6), 488-494.

Dorman DC, Struve MF, Vitarella D, Byerly FL, Goetz J, Miller R. Neurotoxicity of manganese chloride in neonatal and adult CD rats following subchronic (21-day) highdose oral exposure. J Appl Toxicol. 2000 May-Jun;20(3):179-87. doi: 10.1002/(sici)1099- 1263(200005/06)20:3<179: aid-jat631>3.0.co;2-c. PMID: 10797470.

Food and Nutrition Board (2002) Dietary Reference Intakes: Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. pp. 10-1 - 10-22. National Academy Press, Washington, DC:

Frisbie SH, Mitchell EJ, Roudeau S, Domart F, Carmona A, Ortega R. Manganese levels in infant formula and young child nutritional beverages in the United States and France:

Comparison to breast milk and regulations. PLoS One. 2019 Nov 5;14(11): e0223636. doi: 10.1371/journal.pone.0223636. PMID: 31689314; PMCID: PMC6830775.

Health Canada Guidelines for Canadian Drinking Water Quality. Guidelines for Canadian Drinking Water Quality. Retrieved from http://www.hc-sc.gc.ca/ewh-semt/pubs/watereau/index-eng.php#tech_doc Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington (DC): National Academies Press (US); 2001. Available from:
https://www.ncbi.nlm.nih.gov/books/NBK222310/ doi: 10.17226/10026 Kern CH, Stanwood GD, Smith DR. Preweaning manganese exposure causes hyperactivity, disinhibition, and spatial learning and memory deficits associated with altered dopamine receptor and transporter levels. Synapse. 2010 May; 64(5):363-78. doi: 10.1002/syn.20736. PMID: 20029834; PMCID: PMC2840192. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2840192/
MDH (Minnesota Department of Health). (2020). Toxicological Summary for Manganese, Health Based Guidance for Water Health Risk Assessment Unit, Environmental Health Division, Minnesota Department of Health, St. Paul, MN.

OEHHA (2004). Risk Assessment for Chemicals in Drinking Water: Estimation of Relative Source Contribution. Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, CA. (Presented as a poster at the 43rd annual meeting of the Society of Toxicology, Baltimore, Maryland) OEHHA (2006) Development of Health Criteria for School Site Risk Assessment pursuant to Health and Safety Code Section 901(g): Child-Specific Reference Dose (chRD) for School Site Risk Assessment – Manganese and Pentachlorophenol (Final) https://oehha.ca.gov/media/downloads/crnr/mn-pcpfinal-070306.pdf

Darrin Polhemus, Deputy Director - 8 - April 7, 2022
OEHHA (2008). Air toxics hot spots risk assessment guidelines: technical support document for the derivation of noncancer reference exposure levels. Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, CA.

OEHHA (2012). Air Toxics Hot Spots Program Risk Assessment Guidelines: Technical Support Document for Exposure Assessment and Stochastic Analysis. Chapter 8: Water Intake Rates. Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California.

OEHHA (2015). Public Health Goal: Perchlorate in Drinking Water. Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California.

OEHHA (2021). Notification Level Recommendations: Perfluorobutane Sulfonic Acid in Drinking Water. Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California O'Neal SL, Zheng W. Manganese Toxicity Upon Overexposure: A Decade in Review.

Curr Environ Health Rep. 2015 Sep; 2(3):315-28. doi: 10.1007/s40572-015-0056-x.

PMID: 26231508; PMCID: PMC4545267.

Tran TT, Chowanadisai W, Lönnerdal B, Le L, Parker M, Chicz-Demet A, Crinella FM.

Effects of neonatal dietary manganese exposure on brain dopamine levels and neurocognitive functions. Neurotoxicology. 2002 Oct; 23(4-5):645-51. doi:

10.1016/s0161-813x (02)00068-2. PMID: 12428736.

U.S. Environmental Protection Agency (EPA). (2004). Drinking Water Health Advisory for Manganese. Retrieved from https://www.epa.gov/sites/production/files/2014- 09/documents/support_cc1_magnese_dwreport_0.pdf
Wasserman, G. A., Liu, X., Parvez, F., Ahsan, H., Levy, D., Factor-Litvak, P., Graziano, J. H. (2006). Water manganese exposure and children's intellectual function in Araihazar, Bangladesh. Environ Health Perspect, 114(1), 124-129.

World Health Organization (WHO). (2004). Manganese in drinking water - background document for development of WHO Guidelines for drinking-water quality. Retrieved from http://www.who.int/water_sanitation_health/dwq/chemicals/manganese.pdf Other Resources
Goeden H. Focus on Chronic Exposure for Deriving Drinking Water Guidance Underestimates Potential Risk to Infants. Int J Environ Res Public Health. 2018 Mar 14;15(3):512. doi: 10.3390/ijerph15030512. PMID: 29538282; PMCID: PMC5877057.

Ljung K, Vahter M. Time to re-evaluate the guideline value for manganese in drinking water? Environ Health Perspect. 2007 Nov;115(11):1533-8. doi: 10.1289/ehp.10316.

PMID: 18007980; PMCID: PMC2072823.

Darrin Polhemus, Deputy Director - 9 - April 7, 2022
Menezes-Filho JA, Bouchard M, Sarcinelli Pde N, Moreira JC. Manganese exposure and the neuropsychological effect on children and adolescents: a review. Rev Panam Salud Publica. 2009 Dec;26(6):541-8. doi: 10.1590/s1020-49892009001200010. PMID:
20107709.

Mitchell EJ, Frisbie SH, Roudeau S, Carmona A, Ortega R. How much manganese is safe for infants? A review of the scientific basis of intake guidelines and regulations relevant to the manganese content of infant formulas. J Trace Elem Med Biol. 2021 May; 65:126710. doi: 10.1016/j.jtemb.2020.126710. Epub 2020 Dec 25. PMID: 33450552.

Scher DP, Goeden HM, Klos KS. Potential for Manganese-Induced Neurologic Harm to Formula-Fed Infants: A Risk Assessment of Total Oral Exposure. Environ Health Perspect. 2021 Apr;129(4):47011. doi: 10.1289/EHP7901. Epub 2021 Apr 13. Erratum in: Environ Health Perspect. 2021 May; 129(5):59002. PMID: 33848192; PMCID:

PMC8043326.

U.S. Department of Agriculture and U.S. Department of Health and Human Services (2020). Dietary Guidelines for Americans, 2020-2025. Retrieved from:
https://www.dietaryguidelines.gov/sites/default/files/2021- 03/Dietary_Guidelines_for_Americans-2020-2025.pdf
Wasserman, G. A., Liu, X., Parvez, F., Factor-Litvak, P., Ahsan, H., Levy, D., Graziano, J. H. (2011). Arsenic and manganese exposure and children's intellectual function.

Neurotoxicology, 32(4), 450-457. doi: S0161-813X (11)00056-8 Yoon, M., Schroeter, J. D., Nong, A., Taylor, M. D., Dorman, D. C., Andersen, M. E., & Clewell, H. J., 3rd. (2011). Physiologically Based Pharmacokinetic Modeling of Fetal and Neonatal Manganese Exposure in Humans: Describing Manganese Homeostasis during Development. Toxicological Sciences: an official journal of the Society of Toxicology, 122(2), 297-316. doi:10.1093/toxsci/kfr141
cc: Robert Brownwood, Assistant Deputy Director, DDW, SWRCB Kurt Souza, Assistant Deputy Director, DDW, SWRCB
Dan Newton, Assistant Deputy Director, DDW, SWRCB
Randy Barnard, Technical Operations Section Chief, DDW, SWRCB Melissa Hall, RDU Chief, DDW, SWRCB

Outlook
Public Comment Public Forum 10/13/26
From Michelle Covell <[email protected]>
Date Fri 10/9/2026 11:51 AM
To Andrew Bradley <[email protected]>
Cc Public Comment <[email protected]>
1 attachment (2 MB)
public health goal for manganese.pdf;
Hi Andrew
Please find pdf attached for another public comment.

The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St. Helena or the St. Helena Planning Commission.

Michelle Liu Covell
Resident, Architect

Outlook
10/13/26 public forum
From Michelle Covell <[email protected]>
Date Fri 10/9/2026 12:16 PM
To Andrew Bradley <[email protected]>
Cc Public Comment <[email protected]>
1 attachment (641 KB)
atretic encephalocele.pdf;
Hi Everyone.

Isaac’s mom here.

I don’t know for certain what caused Isaac’s encephalocele.

However, I have been doing some research and there is a link to high levels of Manganese during pregnancy causing neural tube defects.

I would recommend, I am not a doctor or a scientist, so I am not making medical advice, but might want to find a cleaner source of water if you’re pregnant.

Also when mixing formulas do not use water from the tap here.

Attached pdf has a little clip of what the doctors told me about my baby.

He was the chief pediatric neurosurgeon at Stanford.

I hope no one else has to go through this.

Sincerely,
The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St. Helena or the St. Helena Planning Commission.

Michelle Liu Covell

Outlook
public forum comment 7, for 10/13/26
From Michelle Covell <[email protected]>
Date Tue 10/13/2026 12:08 PM
To Andrew Bradley <[email protected]>; Public Comment <[email protected]>

1.47 mg/L is 2,840% above the SMCL of 0.05 mg/L
Two thousand eight hundred and forty percent.

Here’s the link to some documents and levels I think you should be aware of. The water that we receive at our tap needs to be safe. https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Notices.html

The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St. Helena or the St. Helena Planning Commission.

Michelle Liu Covell
Resident, Architect

Outlook
public comment 8 forum 10/13/26
From Michelle Covell <[email protected]>
Date Tue 10/13/2026 12:16 PM
To Andrew Bradley <[email protected]>
Cc Public Comment <[email protected]>
1 attachment (490 KB)
manganese-nl-issuance-2026.pdf;
Hi Andrew,
Please find attached pdf for public comment.
https://content.govdelivery.com/accounts/CAWRCB/bulletins/41d674f 2026
Additional information is available on the Division’s websites:

Notification Levels:
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/NotificationLevels.html Manganese Revised Notification and Response Level Issuance Document:

https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/docs/2026/manganese-nl-issuance-2026.pdf Manganese:
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Manganese.html Manganese Frequently Asked Questions:
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/docs/2026/mn-faq.pdf Thank you,
The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St.

Helena or the St. Helena Planning Commission.

Michelle Liu Covell
Resident, Architect

1 NOTIFICATION AND RESPONSE

LEVEL ISSUANCE
FINDINGS:

General Background on Notification and Response Levels and Specific Requirements

1. Health and Safety Code sections 116455 and 116456 authorize the State Water Resources Control Board (State Water Board) to issue or revise notification and response levels for contaminants in drinking water delivered for human consumption before primary maximum contaminant levels (MCLs) are adopted. Pursuant to subdivision (k)(2) of section 116271 of the Health and Safety Code, the Deputy Director of the Division of Drinking Water (DDW) is delegated through the State Water Board’s authority to issue notification and response levels.

2. Health and Safety Code section 116455, subdivision (c)(3), defines notification levels as the concentration level of a contaminant in drinking water delivered for human consumption that has been determined, based on available scientific information, to not pose a significant health risk but which warrants notification to the governing bodies.

Notification levels are nonregulatory, health-based advisory levels for contaminants that are established as precautionary measures.

3. Response levels are established in conjunction with notification levels. Health and Safety Code section 116455, subdivision (c)(4), defines response levels as the concentration of a drinking water contaminant above which additional steps, beyond notification to the governing bodies, are recommended to reduce public exposure. As with notification levels, response levels are not drinking water standards.

4. The adoption or revision of notification levels and response levels does not trigger new monitoring requirements for public water system for the contaminant. However, within Contaminant: Manganese
Notification Level: 0.05 milligrams per liter (mg/L)
[Based on a running annual average (RAA)]*
Response Level: 0.20 milligrams per liter (mg/L)
[Based on a single confirmed detection]**
Analytical Method: EPA Methods 200.7 or 200.8 or
Standard Methods 3113 B or 3120 B
Toxicological Endpoint: Neurotoxicity in rats
*Average concentration of four (4) consecutive quarterly samples. **Following an initial detection a repeat sample is collected and analyzed, and the two values are averaged to confirm the initial detection pursuant to Finding 24.

2 NOTIFICATION AND RESPONSE

LEVEL ISSUANCE
30 days after a public water system learns of a confirmed detection exceeding an MCL, notification and/or response level, the public water system must notify its governing body of the exceedance(s) and any relevant governing bodies of the areas it serves (Health and Safety Code section 116455).

5. Public water systems regulated by the California Public Utilities Commission shall also notify the commission when exceeding an MCL, a notification level and/or a response level. The commission may order further action to ensure a potable water supply.

6. Health and Safety Code section 116450, subdivision (e) authorizes the State Water Board to require a public water system to notify its customers to avoid internal consumption of the water supply and use bottled water due to a chemical contamination problem that may pose a health risk. Health and Safety Code section 116450, subdivision (g), further requires certain customers (such as schools, rental properties, and businesses) to provide the same notice to those consuming the water.

7. Public water systems or water agencies subject to recycled water regulations (Cal.

Code Regs., tit. 22, div. 4, ch. 3) or direct potable reuse project monitoring requirements (Cal. Code Regs., tit. 22, section 64669.65) have additional requirements related to MCLs and notification levels.

Information on the Contaminant and the Issuance

8. Manganese is an essential nutrient and enzyme cofactor that is naturally present in many foods and available as a dietary supplement. Despite its nutritional benefits, adverse health effects can be caused by over-exposure. Formula-fed infants may be particularly susceptible to adverse neurotoxicological effects from manganese exposure because they absorb and retain more manganese than adults. Public health notification and related mitigation can protect formula-fed infants by notifying parents and caregivers that short periods of manganese exposure above the response level in formula-fed infants may lead to developmental impacts.

For additional information see the following website:
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Manganese.html

9. In accordance with Health and Safety Code, 116275 subdivision (d), secondary MCLs control contaminants that primarily affect aesthetic qualities and consumer acceptance such as discolored water, staining of fixtures or clothing, and taste and odor. These standards apply to community water systems only. Non-community systems, including non-transient non-community systems such as schools and workplaces, are not subject to secondary standards.

10. California established a manganese secondary MCL of 0.05 mg/L. Exceedance of the secondary MCL is determined with a running annual average of four (4) consecutive quarters and carries monitoring and public notification requirements in accordance with

3 NOTIFICATION AND RESPONSE

LEVEL ISSUANCE
Article 16 and Article 18 of title 22, division 4, chapter 15 of the California Code of Regulations.

11. The revised notification level for manganese cancels applicability of manganese secondary MCL waivers in accordance with California Code of Regulations, title 22, division 4, chapter 15, section 64449.2, which disallows waivers for source water quality above the notification level. These systems will be required to comply with the secondary MCL monitoring, public notice, and treatment requirements.

12. In 2003, manganese notification and response levels were set at 0.5 mg/L and 5 mg/L, respectively, based on neurotoxicity.

13. In April 2022, DDW staff conducted a literature search for human and animal research that studied adverse health effects from manganese exposures specifically by route of ingestion. This literature review indicated that the then-current notification level of 0.5 mg/L and response level of 5 mg/L should be revised downward based on the potential risk for manganese-induced neurological impacts in formula-fed infants.

DDW staff derived a health protective concentration (HPC) equivalent to 0.02 mg/L, to serve as the basis for future recommended revisions to the current manganese notification and response levels. For contaminants like manganese with non-cancer health risks, a response level concentration up to 10 times the HPC is consistent with an acceptable margin of safety.

14. In a technical memorandum dated April 7, 2022, DDW requested that the Office of Environmental Health Hazard Assessment (OEHHA) review staff’s HPC assumptions and derivations and provide comments.

15. On May 3, 2022, OEHHA provided its review, supporting the intermediate approach used to derive the HPC and agreed with the parameters used in the calculation of the HPC, including use of the Kern et al. (2010) study, the composite uncertainty factor of 1,000, the relative source contribution of 0.2, and the drinking water intake of 0.237 liters per kilogram per day (L/kg-day) based on infants aged 0 to 6 months.

16. In accordance with Health and Safety Code section 116456, on February 16, 2023, DDW provided email notice and posted on its website: (1) proposed revised manganese notification and response levels of 0.02 mg/L and 0.2 mg/L, respectively, (2) the technical memorandum, and (3) OEHHA’s comments on the technical memorandum.

17. On March 21, 2023, DDW presented an informational item on the proposed revised manganese notification level of 0.02 mg/L and response level of 0.2 mg/L during the regularly noticed meeting of the State Water Board.

18. As a result of comments received on the February 16, 2023 proposal and the March 21, 2023 State Water Board informational item, the revision to the manganese notification level was modified to:

4 NOTIFICATION AND RESPONSE

LEVEL ISSUANCE
• Align with the public health benefit provided by existing water quality regulations for bottled water. Replacement water, such as bottled water and water from vending stations, is regulated by the California Department of Public Health, Food and Drug Branch, which enforces a manganese concentration limit of 0.05 mg/L. • Align with manganese secondary MCL public notice requirements for community water systems. Although the consumer acceptance-based secondary MCL and health-based notification level serve different functions, establishing the secondary MCL and notification level at the same value provides the State Water Board authority to require community water systems to notify both the governing body and public of an exceedance in accordance with section 116455 of the Health and Safety Code and Article 18 of title 22, division 4, chapter 15 of the California Code of Regulations, respectively. Transient non-community and non-transient noncommunity water systems must also notify its governing body when the notification level is exceeded (Health & Safety Code, section 116455.) https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Notices.html • Account for the fluctuation of manganese levels over time. Exceedance of the notification level for manganese is based on a running annual average to support communication of manganese trends. A sudden increase in manganese concentration above the response level warrants further action to reduce public exposure.

19. In accordance with Health and Safety Code section 116456, on September 4, 2025, DDW provided email notice and posted the proposed revisions to the notification level of

0.05 mg/L (RAA) and response level of 0.20 mg/L for manganese on its website.

20. In accordance with Health and Safety Code section 116456, on October 7, 2025, DDW presented an informational item on the proposed revised manganese notification level of

0.05 mg/L and response level of 0.20 mg/L during the regularly noticed meeting of the State Water Board.

21. Documents related to the development of the notification and response levels described herein are available at
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/NotificationLevels.ht ml.

Recommendations and Requirements for Public Water Systems

22. Due to the health concerns associated with manganese, DDW recommends that samples be analyzed and results reported electronically to the public water system and DDW as soon as practicable, but no later than 30 days following the date of sample collection.

5 NOTIFICATION AND RESPONSE

LEVEL ISSUANCE

23. Within 30 days after a public water system learns of a confirmed detection exceeding an MCL, notification and/or response level, the public water system must notify its governing body of the exceedance(s) and any relevant governing bodies of the areas it serves (Health and Safety Code section 116455).

24. When a public water system becomes aware of a manganese result greater than the response level, DDW recommends the public water system (a) notify DDW within seven (7) days of the exceedance, and (b) as soon as practicable, but no later than thirty (30) days from becoming aware of the initial exceedance, complete the following process to confirm the response level exceedance:
• Collect and analyze a confirmation sample and receive the results. • If the average of the initial and confirmation manganese sample results exceeds the response level, the initial detection is confirmed. Report the result to DDW within two (2) days of receiving the confirmation result. • If the average of the initial and confirmation manganese sample results does not exceed the response level, report the result to DDW within seven (7) days of receiving the confirmation result.
• If a confirmation sample is not completed as described above, DDW shall treat the initial detection as confirmed.

25. DDW considers the exceedance of the manganese response level to pose a potential health risk to formula-fed infants and recommends notifying customers to use an alternative water supply (bottled water) when preparing formula for infants. Accordingly, pursuant to Health and Safety Code section 116450, to reduce public exposure following a confirmed response level exceedance, as determined pursuant to Finding 24, a community water system must do either of the following within 30 days of the initial exceedance:
• Notify customers to use an alternative water supply (bottled water) when preparing formula for infants. Customers receiving the same notice shall provide public notice to those consuming the water as prescribed by Health and Safety Code section 116450, subdivisions (e) through (g). If consumers have other health issues concerning the consumption of manganese in their drinking water, they may wish to consult their doctor, or
• Mitigate exposure until exceedances cease (take source offline, provide treatment or provision of alternative water)

26. DDW may require the same notice as described in Finding 25 for non-community water systems which exceed the manganese response level pursuant to Finding 24 and serve a vulnerable population, as determined on a case-by-case basis.

6 NOTIFICATION AND RESPONSE

LEVEL ISSUANCE

27. Community water systems must include secondary MCL violations in their annual consumer confidence reports pursuant to Health & Safety Code section 116470 and California Code of Regulations title 22, division 4, chapter 15 sections 64449.4, subdivision (c) and 64480.

28. In addition to the above requirements, DDW recommends public water systems inform customers and consumers about the presence of manganese above the notification or response level and associated health concerns in the annual consumer confidence report.

Therefore, the Deputy Director of DDW establishes a notification level of 0.05 mg/L (RAA) and a response level of 0.20 mg/L (based on a single confirmed detection) for manganese.

Approved:

Darrin Polhemus, P.E. Date
Deputy Director, Division of Drinking Water
State Water Resources Control Board
Signature:

Email: [email protected] 06/02/2026
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Outlook
Public comment 10/13/26 forum
From Michelle Covell <[email protected]>
Date Tue 10/13/2026 12:26 PM
To Andrew Bradley <[email protected]>; Public Comment <[email protected]> 1 attachment (1 MB)
mn-smcl-public-notice-over-rl.pdf;
Hi Andrew,
Please find attached pdf for public comment.

Thank you,
The opinions expressed herein are mine individually and are not intended to represent the official position of the City of St. Helena or the St. Helena Planning Commission.

Michelle Liu Covell
Resident, Architect

Manganese Template 4 (T4)
Public Notice Instructions for Manganese over the Response Level (>0.20 mg/L) for Community Water Systems
(Template Attached)
Manganese is regulated by a 0.05 milligram per liter (mg/L) secondary maximum contaminant level (SMCL) standard to address issues of discoloration, not health concerns. In California, SMCLs are enforceable for community water systems. [Title 22, Chapter 15, Section 64449(a)]
In June 2026, the Division of Drinking Water set a non-regulatory health-based notification level of 0.05 mg/L and response level of 0.20 mg/L for manganese. When concentrations of manganese above the response level occur, there may be potential health concerns for neurological impacts in formula-fed infants.

In accordance with Health and Safety Code (HSC) section 116455 a public water system must inform its governing body, and the governing body of any local agency whose jurisdiction includes the areas supplied with drinking water by the public water system, of concentrations exceeding response level for manganese (see Governing Body Notification and Response Level Template). If the retail water system is regulated by the California Public Utilities Commission, the retail water system shall also notify the commission.

If the response level is exceeded, a public water system will not be allowed a waiver and must take additional action beyond governing body notification to reduce public exposure (i.e. notify the public, treatment, alternate water).

The State Water Board has determined that due to potential neurological impacts in formula-fed infants from drinking water that exceeds the response level, public water systems must notify its customers to consider using an alternative water supply (bottled water) when preparing formula for infants. Accordingly, pursuant to HSC 116450, subdivision (e), the public water system must provide public notification as specified below. Alternatively, the public water system may provide source mitigation (such as taking the affected water source out of service, utilizing treatment or blending, or providing alternative water) within 30 days of the notification of the initial sample exceeding the response level. The water system should notify the Division of Drinking Water (DDW) within seven days of becoming aware of an initial response level exceedance.

Unless otherwise directed by the State Water Board, submit a draft public notice to the State Water Board for review prior to distribution or posting.

Public Notification Requirements
Public water systems must use the methods summarized below as required in sections 64463, 64463.4, and 64465 of Article 18 of title 22, division 4, chapter 15 of the California Code of Regulations and use one or more secondary methods to reach people not likely

Manganese Template 4 (T4)
to be reached by the primary method. If you mail, post, or hand deliver, print your notice on letterhead, if available. HSC 116450 contains additional requirements related to secondary or subsequent notification when the response level is exceeded.

Primary Method
Mail or direct delivery. Notice must be distributed to each customer receiving a bill, including those that provide their drinking water to others (consumers at schools, apartments, or businesses), and other service connections to which water is delivered by the water system.

Secondary Methods
Use one or more of the following methods to reach people who are not likely to be reached by the primary method (water consumers in schools, apartments, buildings, large businesses, dormitories, nursing homes, etc.). Notice must be posted in place for as long as the violation or occurrence continues.

1. Publish notice in a local newspaper.

2. Posting:
a. in conspicuous public places served by the water system b. or on an internet website and/or social media

3. Delivery to community organizations.

The public notice template attached is appropriate for the methods described above.

Modifications of the attached template are allowed; however, you must still include the required elements described herein and included in the notice template. The italicized sections (mandatory health effects, notification language) must remain unchanged. [Health and Safety Code Section 116450(f)].

Multilingual Requirement
Spanish. In addition to English, each public notice must contain information in Spanish regarding (1) the importance of the notice or (2) contain a telephone number or address where Spanish-speaking residents may contact the water system to obtain a translated copy of the public notice or assistance in Spanish.

Non-English-Speaking Groups Other than Spanish-Speaking. For each group that exceeds either 1,000 residents or 10% of the residents in the community served, the public notice must (1) contain information in the appropriate language(s) regarding the importance of the notice or (2) contain a telephone number or address where such residents may contact the water system to obtain a translated copy of the notice or assistance in the appropriate language.

Public Notice Considerations
Consider the following as they apply to this notice:
• Make sure it is clear who is served by your water system -- you may need to list the areas you serve that are impacted.

Manganese Template 4 (T4)
• The notice must be displayed so that it catches people’s attention when printed or posted.
• The message in the notice should not contain technical language or print smaller than 12-point type.
• The notice should use language that provides clear and non-contradictory information.

Corrective Action
In your notice, describe corrective actions you are taking. Do not use overly technical terminology when describing treatment methods. Listed below are some steps commonly taken by water systems with chemical violations. Use one or more of the following actions, if appropriate, or develop your own:
• “We are working with [local/state agency] to evaluate the water supply and researching options to correct the problem. These options may include treating the water to remove manganese or connecting to [system]’s water supply.” • “We have stopped using the contaminated well. We have increased pumping from other wells, and we are investigating drilling a new well.” • “We will increase the frequency at which we test the water for manganese.” • “We have since taken additional samples at this location and had them tested.

They show that we meet the [secondary MCL and notification level and/or] response level.”
After Issuing the Notice
Send a copy of each type of notice and a certificate that you have met all the public notice requirements to the DDW within ten days after you issue the notice [§64469(d)]. You must issue any required follow-up noticing (§64463.4) in addition to meeting any repeat notice requirements the DDW sets.

The State Water Board recommends that you notify hospitals and health professionals in the area of the exceedance. People may call their doctors with questions about how the exceedance may affect their health, and the doctors should have the information they need to respond appropriately. The State Water Board requires the water system to continue notification until the exceedance is corrected.

Manganese in Drinking Water Website:
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Manganese.html Drinking Water Notification Levels Website:
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/NotificationLevels.html

Manganese Template 4 (T4)

IMPORTANT INFORMATION ABOUT YOUR DRINKING WATER
Este aviso contiene información muy importante sobre su agua potable, por favor lea el aviso en español si va aquí incluido. Si el aviso en español no va incluido aquí, contacte al sistema de agua para pedir una copia.
本通知包含有關您飲用水的非常重要資訊。如果此處附有繁體中文通知，請閱讀該通知。
如果此處未附有繁體中文通知，請聯絡供水系統索取一份副本。
本通知包含有关您饮用水的非常重要的信息。如本通知附有简体中文通知，请仔细阅读。
如未附简体中文通知，请联系供水机构索取副本。
Thông báo này có chứa thông n rất quan trọng về nước uống của quý vị. Vui lòng đọc thông báo bằng ếng Việt nếu được đính kèm tại đây. Nếu thông báo bằng ếng Việt không được đính kèm tại đây, vui lòng liên hệ với đơn vị cung cấp nước để yêu cầu một bản sao. ਇਸ ਨੋਿਟਸ ਿਵੱਚ ਤੁਹਾਡੇਪੀਣ ਵਾਲੇਪਾਣੀ ਬਾਰੇਬਹੁਤ ਮਹੱਤਵਪੂਰਨ ਜਾਣਕਾਰੀ ਹੈ। ਿਕਰਪਾ ਕਰਕੇਇਸ ਨੋਿਟਸ ਨੂੰ ਪੰਜਾਬੀ ਿਵੱਚ ਪੜ
ੋਜੇਕਰ ਇਹ ਭਾਸ਼ਾ ਇੱਥੇਸ਼ਾਮਲ ਹੈ। ਜੇਕਰ ਪੰਜਾਬੀ ਨੋਿਟਸ ਇੱਥੇਸ਼ਾਮਲ ਨਹੀ ਂਹੈ, ਤਾਂਿਕਰਪਾ ਕਰਕੇ ਇੱਕ ਕਾਪੀ ਦੀ ਬੇਨਤੀ ਕਰਨ ਲਈ ਵਾਟਰ ਿਸਸਟਮ ਨਾਲ ਸੰਪਰਕ ਕਰੋ।
[System] Has Levels of Manganese
Above the Response Level
Our water system recently exceeded the health-based response level for manganese of

0.20 milligrams per liter (mg/L) and the aesthetic-based secondary maximum contaminant level of 0.05 mg/L based on water discoloration. The response level is a health-based level in which action, such as public notification, source treatment, or removing the source from service, is required to reduce public exposure. Exposure to concentrations of manganese above the response level may cause neurological impacts in formula-fed infants. As our customers, you have a right to know what you should do, what happened, and what we are doing to correct this situation.

We routinely monitor for the presence of drinking water contaminants. Water sample results received on [date] showed manganese levels of [level and units]. The result is above the State Water Board’s established health-based response level and the secondary maximum contaminant level.

The average level of manganese over the last year was [Insert the running annual average result for manganese in mg/L if applicable or table listing quarterly sampling results if results tend to vary].

The State Water Resources Control Board (State Water Board), Division of Drinking Water (DDW) information and frequently asked questions for manganese can be found at:
https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/Manganese.html

Manganese Template 4 (T4)
While we develop a corrective action plan, we strongly recommend consumers do the following:

What should I do?
• Formula-fed infants may experience neurological impacts from manganese exposures above 0.20 mg/L. The State Water Board recommends the use of an alternate water source (bottled water) when preparing formula for infants. • If you have other health concerns regarding your children consuming this water, you may wish to consult your doctor.
• For all other consumers, there is no immediate concern, and you do not need to use an alternative water supply.

What happened? What is being done?
[Describe what happened. Describe corrective action]. We anticipate resolving the problem within [estimated time frame].

For more information, please contact [name of contact] at [phone number] or [mailing address].

Secondary Notification Requirements
You must share this information with all the other people who drink this water, especially those who may not have received this notice directly (for example, people in apartments, nursing homes, schools, and businesses). You can do so by posting this public notice in a public place or distributing copies by hand or by mail.

Upon receipt of a notification of a response level exceedance from a person operating a public water system, this notification must be given to the following affected consumers within 10 days [Health and Safety Code Section 116450(e)-(g)] and remain until the exceedance is corrected:
• SCHOOLS: Must notify school employees, students, and parents (if the students are minors).
• RESIDENTIAL RENTAL PROPERTY OWNERS OR MANAGERS (including nursing homes and care facilities): Must notify tenants. • BUSINESS PROPERTY OWNERS, MANAGERS, OR OPERATORS: Must notify employees of businesses located on the property.

In addition, it is also recommended to give notices to:
• CHILD CARE CENTERS: Must notify employees, students, and parents (if the students are minors).

Manganese Template 4 (T4)
This notice is being sent to you by [system].

State Water System Number: [Insert water system number].

Date distributed: [Insert date the notice is distributed].

Copy to:

Division of Drinking Water District Office
Local Health Department

Alan Galbraith Public Comment 5
August 16, 2026
Honorable Scott R.L. Young
Presiding Judge
Napa County Superior Court
825 Brown Street
Napa CA 94559
In the Matter of:

Napa County Grand Jury 2025-2016 Final Report (June 24, 2026) Lapsed Leadership: At. Helena's Problematic Pipes and Murky Waters Dear Judge Young:

I write one more time because I have come to the conclusion, as hard as it may be, that there is no innocent explanation for the actual rate increase numbers in the Grand Jury's shaded box for the 2011 rate increase and no innocent explanation for either the Grand Jury's recommended or actual rate increase numbers for the 2016 rate increase.

These numbers appear to be manufactured by the Grand Jury; they do not come from the 2011 and 2016 consultant rate reports that the Grand Jury's Report acknowledges were in the Grand Jury's possession.

I am providing my further revised analysis of the Grand Jury Report along with new Exhibit A. I have tabbed and highlighted my analysis so that you can readily grasp the factual basis for my conclusion of no innocent explanation. Exhibit A presents the facts in readily understandable format. In documentary substantiation, I am also enclosing the 2016 rate report along with the covering City Council Resolution No. 2016-162 adopting the rates in the Report. My letter of August 14 included the documents relevant to the 2011 rate increase. I have also included a copy of the Grand Jury Report with yellow highlighting so that your Honor can visually grasp the central materiality of the Grand Jury 2011 and 2016 rate misrepresentations to the Grand Jury's Report.

The St. Helena City Council will be taking up again the Council's proposed response to the Grand Jury Report at its next regular meeting on August 25. It should not be required to finalize responses to a Grand Jury Report, issued by an arm of the Court, when the Court in on notice of likely intentional material falsehood.

Please treat this letter as "Count II" ("Grand Jury Misconduct") of my complaint. It presents an independent and separate ground from the ground ("Review Failures") set forth in my letter to the Court of August 14.

I strongly urge that the Court withdraw the Grand Jury Report before the St. Helena City Council meeting of August 25 when the Council will be considering for a second time the City's responses to the Grand Jury Report.

Respectfully yours,
Alan Galbraith
Mayor, City of St. Helena (2014-16)
Foreperson, Napa County Civil Grand Jury (2013-2014)
[email protected]
* * * * * * * * * *
After Note: When I mailed this letter, I was under the misapprehension that the St. Helena City Council would be agendizing the Grand Jury Report at its next regular meeting. Upon being advised that the matter was concluded, I immediately so informed the Court be email to Court Administration

1 October 12, 2026

APPENDIX A REVISED
I. Introductory Note:

I revise my previously submitted Appendix A to account for the rates approved by the St. Helena City Council on November 28, 2017, in Resolution No. 2017-159. Beginning December 1, 2017, these rates modified the 2016 adopted rates, and extended the rate increases through fiscal year 2023 (ending June 30, 2023). The 2025-2026 Napa County Civil Grand Jury, while it acquired the 2011, 2016, and 2023 water rate studies, did not acquire the 2017 rate study. The 2017 rate process is not mentioned anywhere in the Grand Jury Final Report, Lapsed Leadership: St. Helena's Problematic Pipes and Murky Waters (June 24, 2026).

The 2016 and 2017 rates studies by Hansford Economic Consulting ("HEC") state increases in dollars, not percentages. I have converted them to rounded percentages as the Grand Jury provided 2011, 2016, and 20123 rate increases in percentage form. Grand Jury Report ("GJR"), pp. 11-14. The initial 2016 rate increase took effect on February 1, 2017. The next rate increases are those starting on December 1, 2017.

Note: Appendix A and now this Revised Appendix A do not address either differential (inside-the-city versus outside-the-city rates) or elevated rate charges. The City Council discontinued differential rates at its April 26, 2011, meeting when otherwise approving the rates starting July 1, 2011. The City Council discontinued the only elevated rate (the Meadowood surcharge) in 2016.

I provide in Part III further discussion in two subparts. Subpart A sets forth facts from the contemporaneous record outlining the process that led to adoption of the 2017 rates. Subpart B sets forth my observations and opinions as I look back at the Council 2016/2017 rate process and the Grand Jury Report's omission of that rate process.

II. ST. HELENA ADOPTED WATER RATES IN 2011, 2016, 2017, and 2023 2011 Adopted Water Rates:

FY 2012 58.0%
FY 2013 3.0%*
FY 2014 3.0%
FY 2015 3.0%
FY 2016 3.0%

2 * The actual rates turned out to be slightly less because the City downward adjusted the annual rate increases in conformity with the increases in the Consumer Price Index as calculated by the U.S. Department of Labor for the San Francisco-Oakland-San Jose area.

Source: Staff Report, Agenda Item No. 15, St. Helena City Council Meeting, April 26, 2011, p. 1.

Note: The rate Increases adopted by the City Council on April 26, 2011, effective July 1, 2011, are the same as the "Recommended Rate Increases" in the shaded chart on page 11 of the Grand Jury Report. The Grand Jury’s "Actual Rate Increases" (29%, 3%, 2.5%, 2.6&, 2.6%) in the same shaded chart have no factual foundation. As I have advised the Napa County Superior Court, they are imaginary rates.
2016 Adopted Water Rates, as Modified by 2017 Adopted Rates (Single Family Home):
7 HCF Water Usage 17 HCF Water Usage
FY 2018 (2/8/2017) 39% [39%] * 31% [31%]
FY 2018 (12/1/2017) ** 16% [18%] 12% [17%]
FY 2019 2% [14%] 1% [14%]
FY 2020 7% [5%] 7% [1%]
FY 2021 6% [1/2%] 4% [1/3%]
FY 2022 4% [N.A.] 4% [N.A.]
* Bracketed rate percentages are 2016 rates, provided for ready comparison with 2017 rates. N.A. = Not applicable (2016 rates scheduled through FY 2021). ** Effective December 2017 Billing Cycle (inclusive of service provided in November 2017).

Source: City of St. Helena, (2016) Water and Wastewater Rate Study, Final, October 31, 2016, by Hansford Economic Consulting, p. 15 (Figures 8 & 9); Draft 2017 Water and Wastewater Rates, circulated September 12, 2017, accepted in Resolution No. 2017-129 (September 26, 2017); adopted in Resolution No. 2017-159.

3 Note: The Grand Jury "Recommended Rate Increases" (63%, 15%, 4%,4%, 4%) and the Grand Jury's "Actual Rate Increases" (25%, 3.7%, 3.7%, 3.7%, 3.7%) for fiscal years 2017 through 2021 in the shaded chart on page 13 of its report have no factual foundation. As I have advised the Napa County Superior Court, they are imaginary rates.
2023 Adopted Water Rates:

FY 2024 (9/1/2023) 28%
FY 2025 (7/1/24) 8%
FY 2026 (7/1/25) 8%
FY 2027 (7/1/26) 8%
FY 2028 (7/1/27) 8%
Source: City of St. Helena Water and Wastewater Cost of Service and Rate Study, Final Report (April 20, 2023) by Raftelis Financial Consultants, Inc.

Note: The Grand Jury correctly presents the rates set forth above as "recommended" and "actual" in the shaded box on page 14 of its report.

III. Discussion:

A. The 2017 Water Rates
Resolution No. 2107-129, adopting the 2107 rates, begins with 14 recitals. Of note here, it acknowledges that in 2016 the City contracted with Hansford Economic Consulting ("HEC") to ascertain the level of funding needed by the water system to deliver water meeting federal and state standards, that HEC worked with a resident Task Force to provide input, and that the Council adopted the recommended rates effective with the February 2017 billing cycle. The Resolution then recites that after adoption of the 2016 rates the Council directed formation of an Ad Hoc Utility Rate Committee ("Ad Hoc Committee") to review the 2016 HEC Rate Study and "make recommendations, if any, to the City Council for revisions to the Study and possible adjustments to the rates adopted by City Council on November 29, 2016."
The subsequent chronology, recited in Council Resolution Nos. 2017-129 & 2017- 159, is as follows:

4 • April/May 2017: Ad Hoc Committee meets "numerous times" in open and recorded meetings.
• June 19, 2017: Ad Hoc Committee presents its recommendations to the City Council. City Council discusses each recommendation and provides direction to staff and HEC to complete rate revisions.
• September 12, 2017: City publishes rate models for citizen review and Council consideration.
• September 18, 2017: Council holds special meeting "to discuss the options presented and make recommendations on which rate models to proceed" in establishing revised water rates.
• September 26, 2017: Council approves revised water rates and directs initiation the Proposition 218 process.
• November 28, 2017: Council declares that the City has complied with the Proposition 2018 process, adopts the rates approved on September 26, and directs new rates start with December 2017 billing cycle (November 2017 service).

To reiterate, the foregoing are facts; they cannot be disputed. They were not known to the Grand Jury.

B. Observations and Opinions
When reviewing the Grand Jury Report, I recalled that during my mayorship the community, HEC, City Staff and the Council devoted substantial attention to the Water Enterprise. I failed to recall that we had gone through the rate-making process not just once two times during my four years as mayor. By any standard this is extraordinary oversight of a water enterprise by a city council. The expectation is to go through the ratemaking and Proposition 218 process once, be done with it, and not return to it until the last year of the adopted rates.

Why, then, was there a second look in 2017? The City Council responded to residential concern that the 2016 adopted rates with their substantial increases warranted a further look. The Council determined to do so, making it clear in its authorizing resolution that further review might or might not lead to a reduction in rates.

Then, a new development affecting rates became a significant factor in the rate review process. In the 2016 election St. Helena voters approved a one-half cent local sales tax, thereby providing the City with significant new General Fund revenue. The 2017 Council decided to make a $1.6 million grant made possible by the new revenue to the Water Enterprise Fund to pay for unfunded work to remove Upper York Creek Dam. While

5 the 2016 Ten-Year Schedule of Unfunded Water Improvements (in Future Dollars) showed $900,00 in FY 2018 and $928,696 in FY 2019, the similar 2017 Ten-Year Schedule $47,888 in FY 2018 and $48,362 in FY 2019. The large decline in unfunded cost ($1,732,446), largely made possible by the $1.6 million grant, amounted to about 7.7% of the 2016 unfunded 10- year capital improvement program ($20,799,468). As a result, HEC could eliminate $1.6 million in unfunded cost as well as an additional $132,446 in downward cost revision in developing the 2017 rate models.

In undertaking a review of the 2016 rates, the Council had in mind its experience with the Ad Hoc Revenue Source Task Force that it had re-assembled in 2016 to consider (as I remember but subject to check) whether differential rates, ended in 2011, should be reinstituted and, as the record supports, whether the Meadowood-area surcharge should be discontinued. These had been points of significant public controversy. Based on its work, the Council did not reinstitute differential rates and discontinued the surcharge.

Understanding the value of community input through an ad hoc committee, the Council in 2017 established the Ad Hoc Utility Rate Committee to review the 2016 rates.

As set forth in the chronology above, the Ad Hoc Committee met many times, with public input, HEC input, and Staff input, eventually settling on rate models for City Council consideration. My refreshed memory, as confirmed by recitals in Resolution No. 2107-29, is that the City Council settled on a rate model and then accepted the rates based on that model. Given the effort that had gone into revisiting the 2016 rates, I recall that the Proposition 218 process for the 2017 revisions, which followed Council approval, went smoothly. There was no more public concern that the rates had not been well-considered.

The projects on the 2017 unfunded 10-year capital project schedule, with exception of Upper York Creek Dam and the removal of a $1.3 million "Additional Storage" item, are essentially the same, with refinement in cost-estimating, as some projects on the 2017 schedule were estimated to cost more and some less than on the 2106 schedule. As to the elimination of the "Additional Storage" item, which was set for years six and seven in the 2016 schedule, I cannot recall the need for its inclusion in the 2016 ten-year program or the basis for its deletion in the 2017 ten-year program. I have no reason to question the propriety of the handling of this item. Of importance, both schedules escalated future costs based on the historical Engineering News Record Cost Index 20-year average increase. My point: there was no fooling around with capital costs to achieve the somewhat moderated rates adopted in 2017.

Of significance given the Grand Jury's assertion that the City in the 2016 rates was paying no attention to pipes in the ground (GJR, p. 13 ("no Capital Improvement Projects [in 2016 rates] were dedicated to the distribution system")), both the 2016 and 2017 10-year capital plans included $5,000,000 (rounded) in later years for replacement of greater than 6-inch diameter mains. It should be noted that the Grand Jury narrowly defined

6 "distribution system" to mean pipes in the ground. GJR, p. 9. The schedules listed many projects that in ordinary parlance would be part of a distribution system beyond just pipes in the ground.

The question naturally arises: how did it come about that the Grand Jury did not acquire the 2017 rate study, the resolution approving new rates, and the resolution adopting them? The answer is not directly knowable. There is only one certainty: the person providing the 2011, 2016, and 2023 rates studies did not provide the 2017 study or any Staff Reports or Council Resolutions. It is a reasonable inference that the failure belongs to the instigating local source who appears to have instigated the Grand Jury's interest going all the way back to 2011.

The omission of the 2017 rates in the Grand Jury Report, however it came about, is unforgiveable in a grand jury report devoted to historical rate increases. It cannot be argued that the Council exercised "poor oversight"(e.g., GJR, pp. 3, 26) of the Water Enterprise during my mayorship when it was the subject of intense scrutiny by the Council, City staff, the rate consultant, two ad hoc committees, and the interested public in meeting-after-meeting in 2016-2017.

As set forth in the note below my signature, I have previously commented at length on the Grand Jury Report's many problems. It is hard to rank them but missing the 2017 rate process is surely high among them.

Alan Galbraith
St. Helena Mayor, 2014-18
Note: Galbraith Public Comments 2 & 3, St. Helena City Council Meeting, August 25, 2026: see also Letter, Grand Jury's water report was all wet, St. Helena Star, Week of August 27-September 2, 2026, p. A5 (bullet point summary of Report's problems).

7

City of Saint Helena

PROCLAMATION
Domestic Violence Awareness Month
October 2026
WHEREAS, NEWS, Domestic Violence and Sexual Abuse Services is commemorating 45 years of service to survivors of domestic violence in Napa County, having opened the first confidential safe house on October 5th, 1981, and began providing safety to those escaping abuse; and
WHEREAS, every year since 1989, the United States Congress has proclaimed October as Domestic Violence Awareness Month, renewing our Country’s commitment to standing against domestic violence and meeting the needs of survivors; and WHEREAS, Domestic Violence Awareness Month is about raising awareness and uplifting the needs, voices and experiences of survivors. This year’s national campaign of “With Survivors Always” calls on us to explore what it means to be in partnership with survivors toward safety, support, and solidarity; and
WHEREAS, domestic violence is a public health concern that impacts the well-being and success of individual community members, as well as the community as a whole. Data from the U.S. Center of Disease Control’s 2022 National Intimate Partner and Sexual Violence Survey (NIPSVS) show that nearly 1 in 3 women and 1 in 4 men in the U.S. report experiencing severe physical violence from an intimate partner in their lifetime while nearly half of U.S. adults have experienced psychological aggression such as humiliating or controlling behaviors from their partner. Domestic violence can cause severe physical and emotional distress for survivors who are more likely to become suicidal and lose economic opportunities from the abuse. Children who witness abuse are likely to experience abuse themselves and are often used to control other family members which can have lifelong impacts on their mental health. Aside from the obvious physical and emotional trauma inflicted, domestic violence contributes to over 10% of all intentional violent deaths (not including suicide) and costs America over 8 billion dollars a year; and WHEREAS, by observing October as Domestic Violence Awareness Month we show that our community is committed to supporting survivors and working toward the prevention of domestic violence among future generations.

NOW, THEREFORE LET IT BE RESOLVED THAT I, Paul Jamison Dohring, Mayor, on behalf of the City Council of the City of St. Helena, do hereby proclaim October 2026 as “Domestic Violence Awareness Month”, and encourage all residents of St. Helena to honor domestic violence survivors and those who serve them during this month and throughout the year.

Dated this 13th day of October, 2026
Signed: __________________________
Paul Jamison Dohring, Mayor

Interim
Strategic
Plan:

Building the
Groundwork for
Long-Term
Transformation
and 6-Month
Implementation
4/29/20XX Framework

Goal 2: Organizational Structure
2 Hiring
• City Manager and Director of Finance
• Recruitments Underway
• Library Director and Operations Manager
• Interviews Being Scheduled and Underway
• Capital Improvement Program Manager and
Management Analyst
• Positions Open – CityOfStHelena.gov/HR
• Additional job descriptions and salary schedules
coming to Council on October 27 or November 10

Goal 1: Systems and Procedures
3 SOP and Policy Review
• We have reached out to and spoken with a few firms
• Anticipating to receive proposals in next few weeks

Goal 6: Standards and Service
4 Public Dashboards
• Interim Strategic Plan Dashboard
• Shows progress on the 6 goals
• Performance Measures Dashboard (KPIs)
• Will begin collecting data in November and
update in December
• CityOfStHelena.gov/InterimPlan

5

6

7

09.02 - Water System Update
Joe Leach, PE
Assistant City Manager/Dir of Public Works/
City Engineer
October 13, 2026 1

Water System Update – WQ Challenge
Dr. Najm onsite w/ Operations staff Wed/Thu to investigate/assess. 2

Water System Update
3 • Sampling Water Quality: Launching systemwide baseline testing across all three water sources (Bell Canyon, Stonebridge Wells, and Napa water) to track chemical changes throughout treatment, storage, and distribution.

Developing w/ WQ Expert Dr. Issam Najm. Commence by mid-October. • 10/13 Update: Presented to W/WW AC on 10/8 w/ feedback; need to finalize locations/outreach w/ customers.
• Inspecting Pipe Interiors: Deploying CCTV cameras in the coming weeks to inspect 2,900 feet of priority distribution pipes, directly mapping physical pipe conditions and sediment buildup. This information will serve as a baseline and will be used to extrapolate conditions elsewhere in our distribution system. May incorporate into Systemwide Flushing; Issued PO for “select” CCTV of Bell Canyon Transmission Main inspection; expect mobilization NEXT WEEK, 9/29-10/2.
• 10/13 Update: onsite today; expect BC Transmission Main inspection via 3 hydrants/blow-offs to be completed by COB Friday; video available next week.

Water System Update
4 • Accessing Transmission Mains: Coordinating with specialized vendors to engineer access points for CCTV inspection inside the main Bell Canyon transmission pipeline. Staff to develop bid docs for additional hot tap/access port locations; issue by end of October.
• 10/13 Update: still developing.
• Testing Structural Integrity: Assessing leak detection and structural integrity technologies for evaluation of major transmission mains (Bell Canyon and Napa Intertie) to prioritize pipeline replacements. Negotiating contract w/ vendors (Echologics/Mueller & Kenwave) to perform condition assessment (e.g. pipe wall integrity and leak locations).
• 10/13 Update: still developing.

Water System Update
5 • Cleaning and Flushing Systems: Designing the next complete (~45 pipe miles) active system-flushing phase, establishing strict pre- and post-cleaning metrics to verify long-term effectiveness. Expect authorization of distribution system flushing at 10/13 Council meeting.
• 10/13 Update: precon tomorrow a.m.; expect to commence flushing last week of October; start from the south and move northward.
• Communications Campaign: website, social media, door hangers; Website graphic to represent schedule/progress in advance of commencement.
• Upgrading Storage Tanks: Executing an interior rehabilitation of Tank 2 during the upcoming off-peak season and completing a debris inspection of Tank 1A this Fall. Seeking vendor to perform dive/drone inspection of debris disposition in T1A by end of Oct.
• 10/13 Update: T2 Rehab – internal meeting to discuss logistics associated with T2 evacuation/rehab; must have WTP consistently operational in advance • T1A evacuation: inspection yielded less than 1-inch of debris accumulation. Diver scheduled for Halloween weekend to evacuate debris.

Water System Update
6 • Modernizing Operations: Upgrading SCADA control systems, updating asset management protocols, and finalizing long-term pipe replacement schedules. Expect award of systemwide 100% SCADA upgrades design at 10/13 Council meeting; commence GIS data collection in-field operations mid-October. • 10/13 Update: item on this agenda for SCADA design services; expect to have Bid Documents by mid-February
• Expert Services Support: Engage additional expert(s) to review mitigation strategy. Staff to assemble “Strategy Package” to provide industry expert firms for proposal solicitation for issuance by midOctober. • 10/13 Update: Hazen & Sawyer developing proposal.
• Website Dashboard: Develop dashboard for public engagement on “Plan” status. Staff to deploy portal in advance of 10/13 Council meeting.
• 10/13 Update: reference “skeleton” dashboard; provides both Gantt Chart graphic and verbiage to reflect Past, Present and Pending
• https://app.powerbi.com/view?r=eyJrIjoiMWE4YzQxMWUtMzVmNS00M2EwLTk4OTEtOWFmZjliMDI5ODRhIiwidCI6IjMzYzM3MjY2LTY5OWEtNDNhYS05YzMyLWUyODZlMDg5MTky MyJ9

Questions

Agenda Report to the City Council
Agenda Section: CONSENT ITEMS
Department: Community Development Department - Planning Division DATE: October 13, 2026
FROM: Leza Mikhail, Director of Community Development
SUBJECT: Planning Commission By-Laws – Proposed Amendments

RECOMMENDED
ACTION:

Adopt a resolution approving the proposed amendments to the City of St. Helena Planning Commission By-Laws.

PREVIOUS COUNCIL
ACTION:

July 17, 2018 – Amended the Planning Commission By-laws

STATEMENT OF THE
PURPOSE:

Update the Planning Commission By-Laws to update
nomenclature, accurate citations, provide clarification to reflect current processes, and provide consistency with the existing Municipal Code.

FINANCIAL IMPACT: None
CEQA DETERMINATION: Not a project pursuant to CEQA Guidelines Section 15378(b)(5).

BACKGROUND:

The City of St. Helena Planning Commission By-Laws establish rules governing the organization of the City’s Planning Commission, the convening and conduct of the Commission meetings, and the transaction of Commission business when acting in an official capacity.

The existing By-Laws were adopted in 2018. The proposed amendments update the By-Laws to address minor clarifications and changes to Commission procedures, meeting administration, agenda organization, public hearing procedures, and other provisions governing the conduct of Commission business.

Under the City’s applicable procedures and the Planning Commission By-Laws, amendments recommended by the Planning Commission are subject to final approval by the City Council.

The proposed amendments are presented in redline form as an attachment to this report for the Commission's review.

DISCUSSION:

The proposed amendments are intended to update and clarify the Planning Commission ByLaws and improve the organization and administration of Commission meetings. The principal

amendments are summarized below.

Organization and Officers
The proposed amendments revise provisions governing the election and duties of Commission officers. The revised provision continues to provide for annual election of the Chair and Vice Chair, while adding procedures to address vacancies resulting from resignation. In the event of a Chair vacancy, the Vice Chair would serve as acting Chair until a new Chair is formally elected.

While the originally proposed amendments introduced annual rotation of the Chair and Vice Chair positions as a general practice intended to provide Commissioners opportunities to serve in leadership roles, while recognizing that a Commissioner may decline to serve in either position, a majority of the Commission recommended not including this general practice. As such, the version of the By Laws before the City Council do not include this measure.

The amendments also clarify the administrative roles of the Secretary of the Commission and the City Attorney. The Secretary would generally be the Director of Community Development or the Director's designee and would remain responsible for the preparation of the Commission minutes and maintenance of Commission records. The City Attorney would continue to be the designated legal counsel to the Planning Commission.

These changes are intended to provide greater clarity regarding Commission leadership and administrative responsibilities.

Meeting Schedule and Administration
One of the more substantive proposed amendments concerns the Commission’s regular meeting schedule. The proposed amendments revise the provisions governing regular Commission meetings. The By-Laws currently provide for regular meetings on the first and third Tuesdays of the month. The proposed language provides for one regular meeting per month, designated for the third Tuesday, while retaining provisions addressing holidays, additional or special meetings, meeting locations, and notice requirements.

The amendments also update the provisions governing emergency and special meetings and address circumstances in which a quorum is not available.

This proposal for future amendments to the Commission’s By-Laws with respect to holding one meeting a month was presented as a matter of Department operations at a previous Planning Commission meeting during the Director’s report. At that time, the Director also noted that the change was also in line with the City’s Municipal Code Section 2.60.030 of the St. Helena Municipal Code, which states that the Planning Commission shall meet a minimum of one day a month.

Agenda and Order of Business
The proposed amendments update both the provisions governing preparation of

Planning Commission agendas and revise the regular order of business.

The amendments retain the requirement that an agenda be prepared for each Planning Commission meeting and continue to require matters presented to the Commission to comply with applicable City requirements. The proposed order of business is also reorganized and consolidated. Among other changes, the revised list replaces the existing "Scheduled Matters" category with "Other Business" and modifies the organization of staff and Commission reports and the agenda forecast.

The proposed revisions are intended to make the regular order of business more straightforward and easier to administer while maintaining the major types of business regularly considered by the Commission.

Public Hearings and Public Participation
The proposed amendments update the procedures governing public hearings and public participation. The revised provisions address written materials submitted before and after distribution of the agenda packet, public testimony, applicant or appellant presentations, Commission questions, responses to issues raised during testimony, deliberation, motions, and voting.

The proposed By-Laws continue to provide an opportunity for members of the public to address the Commission and establish the sequence for presentations and testimony during a public hearing. The Chair would continue to manage the order and timing of presentations and public testimony consistent with the By-Laws.

The proposed amendments also clarify the sequence of a public hearing, including opening the hearing, disclosure of ex parte communications, presentation of the staff report, applicant or appellant presentation, Commission questions, public testimony, responses to information raised during testimony, closure of the public hearing, Commission deliberation, motion-making, and voting.

These revisions are intended to improve clarity concerning the sequence and administration of Planning Commission public hearings.

Voting, and Parliamentary Procedure
The proposed amendments also continue to require Commissioners to conduct their duties in accordance with the City's applicable Standards of Conduct and Meeting Procedures and retain provisions addressing conflicts of interest under State law and applicable City procedures. These provisions reinforce the expectation that Commissioners conduct official business consistently with applicable legal and City requirements.

Administrative and Housekeeping Amendments.

In addition to the substantive procedural revisions described above, the redline includes updates to terminology, titles, addresses, rule numbering, dates, and other administrative provisions. These changes are intended to improve the accuracy, clarity, and

organization of the By-Laws and to reflect current City terminology and administrative practices.

ADDITIONAL INFORMATION
The proposed amended Planning Commission By-Laws are provided in both redline and clean form for City Council consideration and adoption. The redline version illustrates the edits and amendments proposed for the Planning Commission’s recommendation to the City Council.

The City Council is the ultimate approving body of all Commission By-Laws that have been established throughout the City.

Staff recommends that the City Council review the proposed amendments to the Planning Commission By-Laws, which are consistent with the Department’s operations, capacity and general Work Plan. For these reasons, Staff has prepared amendments that are supported by the Department of Community Development and have been reviewed and supported by the City Attorney.

ENVIRONMENTAL REVIEW:

Approval of an update to the Planning Commission By-Laws is not a project under the California Environmental Quality Act (CEQA), pursuant to CEQA Guidelines Section 15378(b)(5).

GOAL:

Approval of the Amendment to the Planning Commission By-Laws supports City Council Goal 7: “Optimize Organizational Effectiveness.” Additionally, the amended Planning Commission By-Laws support the Implementation Framework for the Interim Strategic Plan (IFISP) approved by the City Council on August 25, 2026. Specifically, Goal 1 of the IFISP to address procedures and policies, some-of-which may necessitate updating.

ATTACHMENTS:

1. Resolution - Planning Commission By-laws

2. PC BY-LAWS 2026-Amendment-Final Clean

3. PC BY-LAWS 2026-Amendment-Final Redline

4. Planning Commission Resolution - PC2026-017

CITY OF ST. HELENA
RESOLUTION NO. 2026-
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF ST. HELENA APPROVING AMENDMENTS TO THE CITY OF ST. HELENA PLANNING COMMISSION BY-LAWS

RECITALS
WHEREAS, the City of St. Helena Planning Commission By-Laws establish rules governing the organization of the Planning Commission, the conduct of Commission meetings, and the transaction of Commission business; and WHEREAS, the existing Planning Commission By-Laws were adopted in 2018; and
WHEREAS, the City has prepared amendments to update and clarify provisions relating to Commission organization and officers, meeting schedules and administration, agenda preparation and order of business, public hearing procedures, Commission conduct, and other administrative matters; and
WHEREAS, the proposed amendments are intended to provide a clearer and more consistent framework for the organization and administration of Planning Commission meetings; and
WHEREAS, amendments to the Planning Commission By-Laws are subject to approval by the City Council; and
WHEREAS, on September 15, 2026, the Planning Commission considered the proposed amendments at a duly noticed public meeting and considered all oral and written information presented regarding the amendments.

WHEREAS, the City Council has considered the proposed amendments, the staff report, the proposed clean and redline versions of the Planning Commission ByLaws, and all oral and/or written information presented regarding the amendments; and NOW, THEREFORE, the City Council of the City of St. Helena resolves as follows:

RESOLUTION
A. CEQA Determination. The City Council finds that the proposed amendments concern internal governmental organization and administrative procedures and do not constitute a “project” subject to the California Environmental Quality Act pursuant to CEQA Guidelines Section 15378(b)(5).

B. The City Council approves the amended City of St. Helena Planning Commission By-Laws, substantially in the form attached hereto as Exhibit A.

C. Effective Date. The amended Planning Commission By-Laws shall become effective upon approval by the City Council.

Approved at a Regular Meeting of the City Council of the City of St. Helena on October 13, 2026, by the following vote:

Mayor Dohring:

Vice Mayor Deasy:

Council Member Barak:

Council Member Diaz:

Council Member Spadarotto:

APPROVED: ATTEST:
________________________ ________________________
Paul Jamison Dohring, Mayor Andrew Bradley, City Clerk

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ST. HELENA PLANNING COMMISSION

BY-LAWS
The following rules shall be applicable to the organization of the St. Helena Planning Commission, to the convening or calling of meetings, and to the transaction of business when the Commission has convened and acts or serves in an official capacity, pursuant to law.

ORGANIZATION AND ELECTION

AND DUTES OF OFFICERS
RULE 1. The Commission shall elect a Chairperson (Chair) and Vice Chairperson (Vice-Chair) and designate a Secretary at the first regular meeting of the Planning Commission in July to serve for a period of one year from the date of their election. However, the Planning Commission, by majority vote, may choose to elect a Chair or Vice-Chair at a different meeting to address a resignation. In the case of a resignation of the Chair, the Vice-Chair shall become the interim Chair until formal election of a new Chairoccurs.

RULE 2. The Chair of the Planning Commission shall preserve order and decorum and shall decide questions of order. The Vice-Chair shall preside in the absence of the Chair.

RULE 3. The Chair of the Planning Commission may second any motion and present and discuss any matter as a member of the Commission without having to step down from the Chair and shall be entitled to vote on all matters before the Planning Commission.

RULE 4. The Secretary shall be a City employee, normally the Director of Community Development, or their designee.

RULE 5. The Secretary, or their designee, shall be responsible for the preparation of the Planning Commission minutes and the Secretary shall assure that all official actions or decisions by the Commission shall be recorded within the minutes. Consistent with Municipal Code Section

2.60.030, the Commission shall keep a public record of its resolutions, transactions, findings and determinations. Those records are kept as minutes that summarize Commission action, in the same manner as City Council minutes.

RULE 6. The City Attorney of the City of St. Helena shall be the legal counsel to the Planning Commission.

RULE 7. The video recordings of each meeting are designated as the official record of the Planning Commission agenda and action and are to be made available on the City of St. Helena website.

RULE 8. To the greatest extent possible, Commissioners should not correspond with each other via email regarding official business of the Commission, or when discussing matters that may be considered at a future public hearing. Commissioners are expected to make independent reviews and decisions on Agendized items that may be presented to the Commission.

SCHEDULE OF MEETINGS

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RULE 9. The Planning Commission shall hold at least one Regular Meeting per month, consistent with Section 2.60.030 of the St. Helena Municipal Code. The designated meeting shall be held on the third Tuesday of the month. In the event the first or third Tuesday is a holiday, an alternate meeting may be held. An additional Adjourned Meeting may be held, if necessary. Such regular meetings may be canceled by a vote of the majority of Commission members present at a regular or special meeting, when a quorum is not available, or if there is a lack of items to be scheduled for consideration at the discretion of the Director of Community Development. Meetings shall be held in the same location used by the City Council or at City Hall or the Fire Department starting at 6:00 P.M. Adjourned Meetings, Special Meetings, meeting relocation, or revised starting time shall be by a three-fifths vote of the Planning Commission. Notice of such meeting shall be given in accordance with State law.

RULE 10. Emergency or special meetings may be called as provided in Section 54956 of the Government Code of the State of California. The Secretary of the Commission or their designee may poll the Commission for a quorum to establish an emergency or special meeting.

RULE 11. In the absence of a quorum for a regularly scheduled meeting, all items on the agenda shall be continued to the next scheduled meeting.

AGENDA
RULE 12. An agenda shall be prepared by the Secretary of the Planning Commission for each meeting of the Planning Commission.

RULE 13. All matters to be considered by the Commission shall be properly filed with the City in compliance with the provisions, standards, and procedures established by adopted City Ordinances and Department application requirements. The Secretary shall not accept for presentation to the Commission any matter unless it is properly made on the prescribed forms and properly filled out with all data attached.

RULE 14. Any matter that comes before the Commission orally under Public Forum shall not be discussed or acted upon by the Commission unless and until it is heard as a scheduled agenda item at a Regular, Adjourned, or Special meeting of the Commission.

RULE 15. Request for informal or advance decisions concerning potential future developments or plans shall not be considered by the Planning Commission.

RULE 16. The regular order of business of the Commission shall be:

1. CALL TO ORDER

2. PLEDGE OF ALLEGIANCE & ROLLCALL

3. MINUTES / CONSENT APPROVAL

4. PUBLIC FORUM

5. CONTINUED ITEMS

6. PUBLIC HEARINGS

7. OTHER BUSINESS

8. REPORTS BY STAFF AND PLANNINGCOMMISSION

9. AGENDA FORECAST

10. ADJOURNMENT

RULE 17. The Chairperson may revise the order of the agenda for a particular meeting in order to expedite business for the convenience of the public or for improved continuity.

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RULE 18. Commission meetings may remain in session up to, but no later than 10:00 P.M.

However, the Commission may, by a unanimous vote, extend the meeting if the Commission deems such extension necessary. Otherwise, the meeting shall be adjourned to another day acceptable to the Commission, or unfinished business may be continued to the next Regular Meeting.

CONDUCT OF PUBLIC HEARINGS
RULE 19. Letters, petitions, or other written material pertaining to any item on the agenda may be filed with the secretary of the Commission prior to the time of the public hearing or may be presented to the Commission at the time of the public hearing. The Commission shall consider such material in deciding any issue before it. All written material shall become part of the Commission’s file on the agendaitem.

RULE 20. Items submitted after packet distribution: Materials related to any item on the Agenda submitted to the Planning Commission after distribution of the agenda packet are available for inspection in the Secretary of the Commission’s office at 1088 College Ave., St. Helena, CA during normal business hours. All such materials will be brought to the meeting and will be available for public inspection at the meeting site. Either City Staff or the Chairperson at the hearing shall give public notice of any such materials. If copies are not available in sufficient quantity for interested parties or members of the public at the hearing, the Chairperson shall take reasonable steps to afford all such persons the opportunity to inspect the materials before the start of the hearing on a scheduled matter. The purpose of the foregoing is to avoid the interruption of testimony with requests for inspection ofmaterials.

RULE 21. Any person desiring to address the Planning Commission may, when recognized by the Chair give his or her name and address. A person appearing in a representative capacity should provide the name and should provide address of each represented party. Each person wishing to speak shall submit a speaker slip to the Secretary or their designee, and the Chair may hear testimony in the following order, when applicable:

1. Applicant and/or Appellant of subject application (if applicable),

2. Public Testimony in the order speaker slips are received, and

3. Rebuttal by Applicant and/or Appellant (if applicable).

RULE 22. Testimony and argument relative to any item scheduled on the agenda as a Public Hearing shall, unless otherwise ordered by the Chair, be presented in the following order and within the time limitsspecified.
a. The Chairshall declare the Public Hearing to be open. b. The Chair shall ask if any Commissioners have any disclosure(s) of Ex Parte Communication* c. Staff Report, including acknowledgement and/or reading of written testimony. d. Presentation of the project by applicants or appellants, and/or agents/consultants directly associated with the project. (10 minutes)
e. Commission questions to staff and the applicant for purposes of clarification of staff report and proposed project.
f. Public Testimony in support or opposition of the project. (4 minutes per person) g. Applicant and/or staff response to new information or questions raised by public testimony. h. Chair declares public hearingto be closed.
i. Planning Commission deliberation, and motion.
j. Roll Call Vote.
k. The Chair shall read Appeal language at the end of any matter where a decision is rendered on an appealable item.

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Note: At the option of the Chair, the public, applicant and/or appellant may give further testimony on a question posed through the Chair, provided it is directly related to a motion.
* Ex Parte Communication is hereby defined as any additional factual information obtained by commissioners that pertains to an individual decision, including visiting a project site, meeting with a project applicant and/or meeting with interested citizens.

RULE 23. The Chair may, in the interest of facilitating the business of the Planning Commission, limit the amount of time that a person may use in addressing the Planning Commission, but in no case shall the limitation be less than one minute. Opponents and proponents shall be given equal opportunity for presentation. A project applicant should always be given the right, reasonable opportunity and time, to respond fully to evidence and arguments presented after the applicant has made his/her opening presentation.

RULE 24. The applicant or his or her appointed representative may, with the permission of the Planning Commission, withdraw, or request a continuance on any matter pending before the Commission at any time prior to the Commission acting on such matter.

VOTING
RULE 25. A majority of the members of the Commission shall constitute a quorum. Unless otherwise required by federal, state or local regulation, the affirmative vote of a majority of the quorum is necessary to take action. If a majority is unable to be assembled on any motion (including a motion to continue a matter to a specific time) relating to a specific project for which the Commission must make a recommendation to the City Council, the project shall be referred to Council with a divided recommendation which reflects the individual votes of the Commissioners.

If a majority is unable to be assembled on any motion (including a motion to continue a matter to a specific time) relating to a specific project for which the Commission has final authority, the matter before the Commission shall be deemed denied and the applicant may appeal such decision in accordance with the applicable rules. A tie vote, or deadlock, constitutes a denial unless the applicant requests a continuance of the item to a subsequent meeting at which a quorum is present, prior to a vote to deny the item.

RULE 26. On matters of procedure or order of business the Chairperson may make a motion and without a second and after calling for objection and hearing none, so order. In the event of objection, the Chairperson shall call for a second and a roll call vote.

MISCELLANEOUS
RULE 27. The Commission shall conduct their duties in keeping with the governing standards as provided by the Rules of Procedure for the Conduct of Meetings and Standards of Conduct document that is adopted by the City Council and amended from time to time, maintaining the highest level of professionalism during their tenure serving the residents of the City of St. Helena.

RULE 28. Unless otherwise provided by these Rules, all proceedings before the Commission shall be conducted in accordance with and pursuant to the parliamentary rules of procedure as prescribed in “Rosenberg’s Rules ofOrder.”
RULE 29. Testimony and argument relative to any other item on the agenda shall generally follow the procedure for a Public Hearing as may be modified at the discretion of the Chairperson.

RULE 30. Any rule of these By-Laws may be altered, amended, or repealed by majority vote of the Commission (subject to approval by the City Council), except that such alteration, amendment, or

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repeal shall not affect any pending matter.

RULE 31. A Resolution of the Planning Commission may be adopted conditionally and referred to the Secretary of the Commission for drafting in proper form.

RULE 32. Commission members shall decide for themselves whether they have a conflict of interest on any matter before the Commission. Such determination shall be made in accordance with State law and the City of St Helena Protocol for Committee, Commissions and Boards or any amendment thereto. When a member has disqualified themselves, they shall remove themself from the dais stating their reasons for conflict of interest. The member shall also remove themself from the meeting room, unless they are permitted to remain for a qualified interest as set forth in State law.

RULE 33. Failure to adhere to any of these rules does not result in the invalidation of any decision or action of the PlanningCommission.

RULE 34. Any violation of these rules does not result in a cause of action against the City of St.

Helena.

RULE 35. Subject to compliance with all established laws and regulations, any violation of these rules shall not impact the outcome of a vote or action on a specific project.

Amended, Approved and Adopted at a Regular Meeting of the City Council on October 13, 2026, by roll call vote.

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ST. HELENA PLANNING COMMISSION

BY-LAWS
The following rules shall be applicable to the organization of the St. Helena Planning Commission, to the convening or calling of meetings, and to the transaction of business when the Commission has convened and acts or serves in an official capacity, pursuant to law.

ORGANIZATION AND ELECTION

AND DUTES OF OFFICERS
RULE 1. The Commission shall elect a Chairperson (Chair) and Vice Chairperson (Vice-Chair) and designate a Secretary at the first regular meeting of the Planning Commission in July to serve for a period of one year from the date of their election. However, the Planning Commission, by majority vote, may choose to elect a Chairperson or Vice-Chairperson at a different meeting to address a resignation. In the case of a resignation of the Chairr, the Vice-Chair shall become the interim Chair until formal election of a new Chairperson occurs.

RULE 2. The Chairperson of the Planning Commission shall preserve order and decorum and shall decide questions of order. The Vice -Chairperson shall preside in the absence of the Chairperson.

RULE 3. The Chairperson of the Planning Commission may second any motion and present and discuss any matter as a member of the Commission without having to step down from the Chair and shall be entitled to vote on all matters before the Planning Commission.

RULE 4. The Secretary shall be a City eEmployee, normally the Planning DirectorDirector of Community Development, or their designee.

RULE 5. The Secretary, or their designee, shall be responsible for the preparation of the Planning Commission minutes and the Secretary shall assure that all official actions or decisions by the Commission shall be recorded within the minutes. Consistent with Municipal Code sSection

2.60.030, the Commission shall keep a public record of its resolutions, transactions, findings and determinations. Those records are kept as minutes that summarize Commission action, in the same manner as City Council minutes.

RULE 6. The City Attorney of the City of St. Helena shall be the legal counsel to the Planning Commission.

RULE 7. The video recordings of each meeting are designated as the official record of the Planning Commission agenda and action and are to be made available on the City of St. Helena website.

RULE 8. To the greatest extent possible, Commissioners should not correspond with each other via email regarding official business of the Commission, or when discussing matters that may be considered at a future public hearing. Commissioners are expected to make independent reviews and decisions on Agendized items that may be presented to the Commission.

SCHEDULE OF MEETINGS

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RULE 89. The Planning Commission shall hold at least two one Regular Meetings per month, consistent with Section 2.60.030 of the St. Helena Municipal Code. The designated meeting which shall be held on the first and third Tuesdays of the month. In the event the first or third Tuesday is a holiday, an alternate meeting may be held. An additional Adjourned Meeting may be held, if necessary. Such regular meetings may be canceled by a vote of the majority of Commission members present at a regular or special meeting, or when a quorum is not available, or if there is a lack of items to be scheduled for consideration at the discretion of the Director of Community Development. Meetings shall be held in the same location used by the City Council or at City Hall or the Fire Department starting at 6:00 P.M. Adjourned Meetings, Special Meetings, meeting relocation, or revised starting time shall be by a three-fifths vote of the Planning Commission.

Notice of such meeting shall be given in accordance with State law.

RULE 910. Emergency or special meetings may be called as provided in Section 54956 of the Government Code of the State of California. The Secretary of the Commission or their designee may poll the Commission for a quorum to establish an emergency or special meeting.

RULE 101. In the absence of a quorum for a regularly scheduled meeting, all items on the agenda shall be continued to the next scheduled meeting.

AGENDA
RULE 112. An agenda shall be prepared by the Secretary of the Planning Commission for each meeting of the Planning Commission.

RULE 123. All matters to be considered by the Commission shall be properly filed with the City in compliance with the provisions, standards, and procedures established by adopted City Ordinances and Department application requirements. The Secretary shall not accept for presentation to the Commission any matter unless it is properly made on the prescribed forms and properly filled out with all data attached.

RULE 134. Any matter that comes before the Commission orally under Public Forum shall not be discussed or acted upon by the Commission unless and until it is heard as a scheduled agenda item at a Regular, Adjourned, or Special meeting of the Commission.

RULE 145. Request for informal or advance decisions concerning potential future developments or plans will shall not be considered by the Planning Commission.

RULE 156. The regular order of business of the Commission shall be:

1. CALL TO ORDER

2. PLEDGE OF ALLEGIANCE & ROLL CALL

3. MINUTES / CONSENT APPROVAL

4. PUBLIC FORUM

5. COMMUNICATIONS & PETITIONS

6. RECOMMENDED CONSENT CALENDAR

7.5.CONTINUED ITEMS

8. SIGN PERMIT/ADMINISTRATIVE DETERMINATION

9. PUBLIC HEARINGS - PLANNING COMMISSION ACTION IS FINAL (DR/UP/VAR/LLA/TPM)

10.6. PUBLIC HEARINGS – PUBLIC

HEARINGS/RECOMMENDATIONS TO CITY COUNCIL
(TSM/ZOTA/GPA/REZONE)

11. NAPA COUNTY REFERRALS

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12.7. SCHEDULED MATTERSOTHER BUSINESS

13.8. REPORTS BY STAFF AND PLANNING COMMISSION

14.9. AGENDA FORECAST

15.10.ADJOURNMENT

RULE 167. The Chairperson may revise the order of the agenda for a particular meeting in order to expedite business for the convenience of the public or for improved continuity.

RULE 178. Commission meetings may remain in session up to, but no later than 10:00 P.M.

However, the Commission may, by a unanimous vote, extend the meeting if the Commission deems such extension necessary. Otherwise, the meeting shall be adjourned to another day acceptable to the Commission, or unfinished business may be continued to the next Regular Meeting.

CONDUCT OF PUBLIC HEARINGS
RULE 189. Letters, petitions, or other written material pertaining to any item on the agenda may be filed with the secretary of the Commission prior to the time of the public hearing or may be presented to the Commission at the time of the public hearing. The Commission shall consider such material in deciding any issue before it. All written material shall become part of the Commission’s file on the agenda item.

RULE 1920. Items submitted after packet distribution: Materials related to any item on the Agenda submitted to the Planning Commission after distribution of the agenda packet are available for inspection in the Secretary of the Commission’s office at 1480 Main Street1088 College Ave., St. Helena, CA during normal business hours. All such materials will be brought to the meeting and will be available for public inspection at the meeting site. Either City Staff or the Chairperson at the hearing shall give public notice of any such materials. If copies are not available in sufficient quantity for interested parties or members of the public at the hearing, the Chairperson shall take reasonable steps to afford all such persons the opportunity to inspect the materials before the start of the hearing on a scheduled matter. The purpose of the foregoing is to avoid the interruption of testimony with requests for inspection of materials.

RULE 201. Any person desiring to address the Planning Commission may, when recognized by the Chairperson, give his or her name and address. A person appearing in a representative capacity should provide the name and should provide address of each represented party. Each person wishing to speak shall submit a speaker slip to the Secretary or their designee, and the Chair may hear testimony in the following order, when applicable:

1. Applicant and/or Appellant of subject application (if applicable),

2. Public Testimony in the order speaker slips are received, and

3. Rebuttal by Applicant and/or Appellant (if applicable).

RULE 212. Testimony and argument relative to any item scheduled on the agenda as a Public Hearing shall, unless otherwise ordered by the Chairperson, be presented in the following order and within the time limits specified.
a. The Chairperson shall declare the Public Hearing to be open. b. The Chair shall ask if any Commissioners have any Ddisclosure(s) of Ex Parte Communication*
c. Staff Report, including acknowledgement and/or reading of written testimony. d. Presentation of the project by applicants or appellants, and/or agents/consultants directly associated with the project. (10 minutes)
e. Commission questions to staff and the applicant for purposes of clarification of staff report

Planning Commission By-Laws
July 17, 2018October 13, 2026
4 of 5
and proposed project.
f. Public Testimony in support or opposition of the project. (4 minutes per person) g. Applicant and/or staff response to new information or questions raised by public testimony. h. Chairperson declares public hearing to be closed.
i. Planning Commission debatedeliberation, and motion.
j. Roll Call Vote.
k. The Chair shall read Appeal language at the end of any matter where a decision is rendered on an appealable item.

Note: At the option of the Chairperson, the public, or applicant and/or appellant may give further testimony on the a question posed through the Chair, provided it is directly related to thea motion.
* Ex Parte Communication is hereby defined as any additional factual information obtained by commissioners that pertains to an individual decision, including visiting a project site, meeting with a project applicant and/or meeting with interested citizens.

RULE 223. The Chairperson may, in the interest of facilitating the business of the Planning Commission, limit the amount of time that a person may use in addressing the Planning Commission, but in no case shall the limitation be less than one minute. Opponents and proponents shall be given equal opportunity for presentation. A project applicant should always be given the right, reasonable opportunity and time, to respond fully to evidence and arguments presented after the applicant has made his/her opening presentation.

RULE 234. The applicant or his or her appointed representative may, with the permission of the Planning Commission, withdraw, or request a continuance on any matter pending before the Commission at any time prior to the Commission acting on such matter.

VOTING
RULE 245. A majority of the members of the Commission shall constitute a quorum. Unless otherwise required by federal, state or local regulation, the affirmative vote of a majority of the quorum is necessary to take action. If a majority is unable to be assembled on any motion (including a motion to continue a matter to a specific time) relating to a specific project for which the Commission must make a recommendation to the City Council, the project shall be referred to Council with a divided recommendation which reflects the individual votes of the Commissioners.

If a majority is unable to be assembled on any motion (including a motion to continue a matter to a specific time) relating to a specific project for which the Commission has final authority, the matter before the Commission shall be deemed denied and the applicant may appeal such decision in accordance with the applicable rules. A tie vote, or deadlock, constitutes a denial unless the applicant requests a continuance of the item to a subsequent meeting at which a quorum is present, prior to a vote to deny the item.

RULE 256. On matters of procedure or order of business the Chairperson may make a motion and without a second and after calling for objection and hearing none, so order. In the event of objection, the Chairperson shall call for a second and a roll call vote.

MISCELLANEOUS
RULE 267. The Commission shall conduct their duties in keeping with the governing standards as provided by the Planning Commission Standards of ConductRules of Procedure for the Conduct of Meetings and Standards of Conduct document that is adopted by the City Council and amended from time to time, maintaining the highest level of professionalism during their tenure serving the residents of the City of St. Helena.

Planning Commission By-Laws
July 17, 2018October 13, 2026
5 of 5
RULE 278. Unless otherwise provided by these Rules, all proceedings before the Commission shall be conducted in accordance with and pursuant to the parliamentary rules of procedure as prescribed in “Rosenbergs’s Rules of Order.”
RULE 2829. Testimony and argument relative to any other item on the agenda shall generally follow the procedure for a Public Hearing as may be modified at the discretion of the Chairperson.

RULE 2930. Any rule of these By-Laws may be altered, amended, or repealed by majority vote of the Commission (subject to approval by the City Council), except that such alteration, amendment, or repeal shall not affect any pending matter.

RULE 30. Any rule of these By-Laws may be temporarily suspended by unanimous consent of the Commission.

RULE 311. A Resolution of the Planning Commission may be adopted conditionally and referred to the Secretary of the Commission for drafting in proper form.

RULE 322. Commission members shall decide for themselves whether they have a conflict of interest on any matter before the Commission. Such determination shall be made in accordance with State law and the City of St Helena Protocol for Committee, Commissions and Boards or any amendment thereto. When a member has disqualified himself/herself, he/she themselves, they shall remove himself/herselfthemself from the dais stating their reasons for conflict of interest. The member shall also remove himself/herselfthemself from the meeting room, unless they are permitted to remain for a qualified interest as set forth in State law.

RULE 333. Failure to adhere to any of these rules does not result in the invalidation of any decision or action of the Planning Commission.

RULE 344. Any violation of these rules does not result in a cause of action against the City of St.

Helena.

RULE 355. Subject to compliance with all established laws and regulations, any violation of these rules shall not impact the outcome of a vote or action on a specific project.

Amended, Approved and Adopted at a Regular Meeting of the Planning CommissionCity Council on July 17, 2018 October 13, 2026, by the following roll call vote. :

MOTION CARRIED BY THE FOLLOWING ROLL CALL VOTE:

AYES: Commissioners Ponte, Monnette and Hardy
NOES: None
ABSENT: Commissioner Knudsen
ABSTAIN: None

CITY OF ST. HELENA PLANNING COMMISSION
RESOLUTION NO. PC2026- 017
A RESOLUTION OF THE PLANNING COMMISSION OF THE CITY OF ST. HELENA

RECOMMENDING THAT THE CITY COUNCIL APPROVE AMENDMENTS TO THE CITY OF ST. HELENA PLANNING COMMISSION BY-LAWS

RECITALS
WHEREAS, the City of St. Helena Planning Commission By-Laws establish rules governing the organization of the Planning Commission, the conduct of Commission meetings, and the transaction of Commission business; and WHEREAS, the existing Planning Commission By-Laws were adopted in 2018; and
WHEREAS, the City has prepared amendments to update and clarify provisions relating to Commission organization and officers, meeting schedules and administration, agenda preparation and order of business, public hearing procedures, motions and voting, Commission conduct, and other administrative matters; and WHEREAS, the proposed amendments are intended to provide a clearer and more consistent framework for the organization and administration of Planning Commission meetings; and
WHEREAS, amendments to the Planning Commission By-Laws are subject to approval by the City Council; and
WHEREAS, on September 15, 2026, the Planning Commission considered the proposed amendments at a duly noticed public meeting and considered all oral and written information presented regarding the amendments.

NOW, THEREFORE, BE IT RESOLVED that the Planning Commission of the City of St. Helena hereby resolves as follows:

RESOLUTION
A. CEQA Determination. The Planning Commission finds that the proposed amendments concern internal governmental organization and administrative procedures and do not constitute a "project" subject to the California Environmental Quality Act pursuant to CEQA Guidelines Section 15378(b)(5).

B. Recommendation. The Planning Commission recommends that the City Council approve the amended City of St. Helena Planning Commission By-Laws, substantially in the form attached hereto as Exhibit A, including any amendments approved by the Planning Commission at its September 15, 2026 meeting.

PC By-Laws
Resolution
s•-ber 9, 2026

Agenda Report to the City Council
Agenda Section: CONSENT ITEMS
Department: Community Development Department - Planning Division DATE: October 13, 2026
FROM: Leza Mikhail, Director of Community Development
SUBJECT: Planning Commission Work Plan for Fiscal Year 2026-27 and Accomplishments for Fiscal Year 2025-26.

RECOMMENDED
ACTION:

Adopt the Planning Commission Work Plan for Fiscal Year 2026- 27, including the Commission’s accomplishments for Fiscal Year 2025-26.

PREVIOUS COUNCIL
ACTION:

N/A

STATEMENT OF THE
PURPOSE:

Present the City’s first Planning Commission Work Plan, intended to be affirmed annually by the City Council to establish clear goals to accomplish each fiscal year for the Planning Commission and Staff.

FINANCIAL IMPACT: No fiscal impact is identified from approval of the Planning Commission Work Plan itself. Implementation is expected to occur through existing departmental operations, resources and/or applicant project submittals that require Planning Commission approval.

CEQA DETERMINATION: Not a CEQA Project (CEQA Guidelines §15378) BACKGROUND:

The Planning Commission is a five-member body appointed by the City Council that serves as the City's advisory body on planning and development matters. Pursuant to Chapter 2.60 of the St. Helena Municipal Code, the Commission carries out duties delegated by the City Council and the Municipal Code, including reviewing development applications, conducting public hearings, making recommendations on planning-related legislative matters, reviewing environmental documents, and evaluating development proposals for consistency with adopted City plans, policies, and regulations.

The City is currently in the process of establishing uniform and prescribed annual work plans for each of its committees and commissions for approval and alignment with City Council goals and available resources by department. On July 7, 2026, the Planning Commission accepted a Draft PC Work Plan for FY 2026-27, and recommends the City Council adopt the PC Work

Plan prepared by Staff for the Fiscal Year 2026-27, and include the Accomplishments of the Planning Commission for Fiscal Year 2025-26. The Work Plan has also been slightly modified by the City Manager to include additional items for the City Council’s consideration to establish an annual strategy for which the Planning Commission and City Staff are expected to focus on.

The PC Work Plan (attached) covers responsibilities and goals to focus on between July 1, 2026 and June 30, 2027, and is being presented to the City Council for final adoption. Future Work Plans are anticipated to be presented to the City Council annually as a “best practice” by June of each fiscal year.

DISCUSSION:

The PC Work Plan establishes a framework and strategy for the Commission's anticipated activities, projects, public hearings, workshops, training, and coordination during the fiscal year. The PC Work Plan is intended to support agenda planning, public transparency, and coordination with City Council priorities. It is guided by adopted Council objectives related to housing, zoning code updates, community enhancement, economic development, permit streamlining, public engagement, interdepartmental coordination, and organizational effectiveness. Several PC Work Plan items are also driven by State housing law, statutory review deadlines, applicant-submitted development applications, and previously initiated policy work directed by the City Council, City Manager and/or Department Director.

Accordingly, the PC Work Plan is intended to remain flexible and may be adjusted as priorities, legal requirements, staff capacity, and City Council direction evolves.

The Planning Commission’s bylaws establish the Commission’s meeting schedule, order of business, and meeting procedures, including scheduled matters and agenda forecasting. The PC Work Plan functions within that existing procedural framework. It does not amend the bylaws, establish new procedural rules, or authorize the Commission to make informal or advance decisions or directives on potential future development applications or policy projects.

Anticipated Projects Under PC Purview
Anticipated land use applications, legislative matters, and policy work include the Alilia Hotel Expansion, 1360 Main Street Redevelopment (Hotel), Adams Street Castellucci Hotel, and Spring Vineyard Housing Project Appeal. The Work Plan also identifies potential Zoning Ordinance amendments addressing accessory dwelling units, short-term rentals, signs, and miscellaneous code updates; review and potential update of the Inclusionary Housing Ordinance; the General Plan Annual Review; establishing a Housing Strategy; review and update of the Planning Commission By-Laws; and review of selected Zoning Ordinance provisions intended to streamline processes and promote economic development.

PC Educational Workshops
Potential educational workshops, subject to Department workload and capacity, include the Brown Act and Robert's Rules of Order; the role of a Planning Commissioner; developing findings, conditions of approval and mitigation measures; architectural plan review and design review guidelines; City communications, engagement programs and tools; Capital Improvement Plans and the Planning Commission's role; and California Environmental Quality Act and State legislative updates, including the Permit Streamlining Act. Additional informational presentations may be coordinated with other City departments, agencies, and

community organizations on emergency preparedness, evacuation and wildfire considerations, regional climate planning, transportation planning, Housing Element and RHNA implementation, LAFCO, the Vine Trail, and local tourism and business organizations.

PC Accomplishments (FY 2025-26)
The FY 2025-2026 accomplishments included Planning Commission recommendations to the City Council on the 1030 Fulton Lane General Plan Amendment; Vision Triangle, Calculation of Floor Area, Short-Term Rental, Alcohol Sales, and On-site Storage Zoning Ordinance amendments; and the Spring Grove, Sylvaner, and Kidd Ranch subdivision/parcel map matters. The Commission also conducted study sessions concerning the 2023 Zoning Code Update, ADU Ordinance Amendment, and Short-Term Rental Ordinance Amendment, and reviewed discretionary development applications including major design review, demolition, conditional use permits/amendments, tentative subdivision maps, and major sign permits.

The Work Plan provides a framework for the Commission's work during FY 2026-27 rather than a fixed schedule of future agenda items. The timing and scope of individual projects may change based on application submittals, City Council direction, Department workload and capacity, legal requirements, and the availability of outside agencies or staff.

ENVIRONMENTAL REVIEW:

Approval of the Planning Commission Work Plan and receipt and filing of the Commission’s accomplishments are administrative actions. No project-specific discretionary approval is being granted by the City Council through this action; therefore, the action is not subject to the Californian Environmental Quality Act (CEQA).

GOAL:

The Work Plan supports the City’s goal of maintaining effective planning and development review processes by establishing a clear framework and strategy for the Planning Commission’s anticipated work, policy review, public hearings, educational works and coordination during a fiscal year. Approval of the annual Planning Commission Work Plan supports City Council Goal 7: “Optimize Organizational Effectiveness.” Additionally, adoption of the Planning Commission Work Plan supports the Implementation Framework for the Interim Strategic Plan (IFISP) approved by the City Council on August 25, 2026. Specifically, Goal 1 of the IFISP to address procedures and policies, some-of-which may necessitate updating, or establishment; and Goal 5 of the IFISP to provide a strategize framework for the Planning Commission and City Council to address priorities which include housing strategy, economic development, the City's downtown, and considerations of the City's Sphere of Influence.

ATTACHMENTS:

1. City_Council_Resolution_PC_Work_Plan_FY2026-27

2. FINAL - PC Work Plan w PC (Updated)

3. FINAL - Planning Commission Work Plan

CITY OF ST. HELENA
RESOLUTION NO. 2026-
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF ST. HELENA ADOPTING THE PLANNING COMMISSION WORK PLAN FOR FISCAL YEAR 2026-27 AND

ACKNOWLEDGING THE PLANNING COMMISSION ACCOMPLISHMENTS FOR FISCAL YEAR 2025-26

RECITALS
WHEREAS, the Planning Commission is a five-member body appointed by the City Council and performs planning and development review responsibilities pursuant to Chapter

2.60 of the St. Helena Municipal Code; and
WHEREAS, the City is establishing annual work plans for its committees and commissions to align their activities with City Council goals and available departmental resources; and
WHEREAS, on July 7, 2026, the Planning Commission accepted a draft Planning Commission Work Plan for Fiscal Year 2026-27 and recommended its adoption by the City Council; and
WHEREAS, the proposed Work Plan, as further modified for City Council consideration, establishes a flexible framework for the Planning Commission’s anticipated projects, policy review, public hearings, workshops, training, and coordination during the period July 1, 2026 through June 30, 2027; and
WHEREAS, the Work Plan is intended to support City Council priorities, public transparency, and effective coordination while remaining subject to applicable law, staff capacity, project submittals, and future City Council direction; and WHEREAS, the Planning Commission’s accomplishments for Fiscal Year 2025-26 are including as reference; and
WHEREAS, the City Council has considered the Planning Commission Work Plan for Fiscal Year 2026-27, the accomplishments for Fiscal Year 2025-26, the staff report, and all oral and written information presented concerning this matter.

NOW, THEREFORE, the City Council of the City of St. Helena resolves as follows:

RESOLUTION
A. CEQA Determination. The City Council finds that adoption of the Planning Commission Work Plan and acknowledgment of the Commission’s prior-year accomplishments are administrative actions that do not constitute a “project” under the California Environmental Quality Act pursuant to CEQA Guidelines Section 15378(b)(5).

B. The City Council adopts the City of St. Helena Planning Commission Work Plan for Fiscal Year 2026-27, substantially in the form attached hereto as Exhibit A, and acknowledges the Planning Commission accomplishments for Fiscal Year 2025-26 included therein.

C. Effective Date. This resolution shall take effect immediately upon its adoption by the City Council.

Approved at a Regular Meeting of the City Council of the City of St. Helena on October 13, 2026, by the following vote:

Mayor Dohring:

Vice Mayor Deasy:

Council Member Barak:

Council Member Diaz:

Council Member Spadarotto:

APPROVED: ATTEST:
________________________ ________________________
Paul Jamison Dohring, Mayor Andrew Bradley, City Clerk

City of St. Helena
Community Development Department
1088 College Avenue
St. Helena, CA 94574
CITY OF ST. HELENA
Planning Commission
Work Plan for Fiscal Year 2026-2027
(July 1, 2026 – June 30, 2027)
&
Accomplishments for Fiscal Year 2025-2026
(July 1, 2025 – June 30, 2026)
Commissioners:

Christopher Warner, Chairperson
Sue Frudek, Vice Chairperson
Autumn Anderson
Michelle Covell
Hector Lopez
Planning Commission Secretary:

Leza Mikhail – Director of Community Development

2 MISSION STATEMENT
The City of St. Helena Planning Commission is a five-member body of community representatives appointed by the City Council. The goal of the Planning Commission is to guide land use and development decisions that implement the City's General Plan, preserve the unique character of St.

Helena, promote housing opportunities, protect community resources, and ensure that growth occurs in a manner that benefits current and future residents.

PLANNING COMMISSION ROLES & RESPONSIBILITIES
Pursuant to Chapter 2.60 of the St. Helena Municipal Code, the Planning Commission serves as the City's advisory body on planning and development matters and is responsible for carrying out duties delegated by the City Council and Municipal Code.

The Planning Commission's primary responsibilities include:
• Reviewing and acting upon development applications as authorized by the Municipal Code. • Conducting public hearings on land use and development matters. • Making recommendations to the City Council regarding amendments to the General Plan, Housing Element, Zoning Ordinance, and other planning-related policies. • Reviewing environmental documents prepared pursuant to the California Environmental Quality Act (CEQA).
• Evaluating development proposals for consistency with adopted City plans, policies, and regulations.
• Providing opportunities for public participation in planning and land use decisions. • Assisting with implementation of State housing laws and local planning initiatives.

FY 2026-27 WORK PLAN
The FY 2026-27 Planning Commission Work Plan should provide the goals/objectives (no more than five) of the workplan, the activities to accomplish the goals, the priority ranking of each goal, and where feasible the timeline anticipated to accomplish the goal.

1. Schedule, notice, and conduct monthly meetings (usually held on 3 rd Tuesday of each month) for
the purpose of carrying out the roles and responsibilities described within this work plan. (Ongoing)

2. Conduct workshops and public hearings, open to the public for the purpose of studying, evaluating, and facilitating decision-making regarding items scheduled for public hearings, or with relevance to land use. Public hearings serve to process certain permit types or legislative actions that require Planning Commission consideration, and workshops serve to educate the Planning Commissioners and members of the public about City planning policies, legal requirements, department procedures, work programs, and other general topics of interest. The

3 types of workshops and public hearing projects/legislative topics that are anticipated to be considered for the FY 2026-27 year are listed below:
o The Department has a general list of anticipated land use application projects/ entitlements, ordinance amendments, and policy documents that may be presented to the Planning Commission during the 2026 - 2027 fiscal year, which includes, but is not limited to, the following projects:
• Alilia Hotel Expansion
• 1360 Main Street Redevelopment
• Adams Street Castellucci Hotel
• Spring Vineyard Housing Project Appeal
• Zoning Ordinance Amendments
- ADU Ordinance Update
- Short-Term Rental Ordinance Update
- Sign Ordinance Update
- Miscellaneous Code Update 1
• Inclusionary Housing Ordinance Review and Potential Update • General Plan Annual Review
• Housing Strategy
• Review and Update of the Planning Commission By-Laws
• Review elements of the Zoning Ordinance to streamline and promote economic development
• Review of subjective and objective sections of the ordinance as determined necessary
o Outside of regularly scheduled public hearing items or projects established by the Community Development Department or by referral by the City Council, workshops for the 2026 - 2027 fiscal year that fall under the purview of the Planning Commission may include the following topics (dependent on Department workload and capacity) suggested throughout the fiscal year, listed in order of priority:
• Brown Act and Robert's Rules of Order (TBD - As necessary) • Role of a Planning Commissioner (TBD – As necessary)
• Developing Findings, Conditions of Approval and Mitigation Measures (TBD – As necessary)
• Architectural Plan Review / Design Review Guidelines (TBD – As necessary) • City’s Communications, Engagement Programs and Tools (TBD) • Capital Improvement Plans and Planning Commission Role (TBD) • California Environmental Quality Act and State Legislative Updates (TBD - As necessary)

4 - Permit Streamlining Act (TBD - As necessary)
• City’s Communications, Engagement Programs and Tools (TBD) • Capital Improvement Plans and Planning Commission Role (TBD) o In addition to the workshop items identified above that fall under the direct purview of the Planning Commission and/or are on the Community Development Department workplan, the following informational/educational workshops are of interest to the Planning Commission. These workshops fall under the purview and/or workplans of other City Departments, outside agencies, or are outside of the Planning Commission purview, and may be scheduled, depending on the availability of requisite outside staff or agency participation:
• Napa County Office of Emergency Services
- Hazard Mitigation Plan Informational Presentation
• St. Helena Evacuation Plan / Wildfire Considerations / Notification Overview • Napa County Regional Climate Action & Adaptation Plan (RCAAP) • Napa Countywide Transportation Plan & Active Transportation Plan • Housing Element and RHNA Implementation
• Napa Local Agency Formation Commission (LAFCO)
• Napa Valley Vine Trail Planning and Implementation
• Our Town St Helena
• Chamber of Commerce & Napa Valley Tourism Corporation (NVTC)

3. Attend the League of California Cities Planning Commissioners Academy (Spring 2027) FY 2025-26 ACCOMPLISHMENTS
During FY 2025-26, the Planning Commission continued to advance City Council priorities, review development applications, and provide policy guidance on a variety of planning matters.

Recommendations to City Council
The Planning Commission reviewed and provided recommendations on the following policy and legislative matters:
• 1030 Fulton Lane General Plan Amendment
• Vision Triangle Zoning Ordinance Amendment
• Calculation of Floor Area Zoning Ordinance Amendment
• Short-Term Rental Zoning Ordinance Amendment
• Alcohol Sales Zoning Ordinance Amendment
• Spring Grove Tentative Subdivision Map
• Sylvaner Tentative Parcel Map
• Kidd Ranch Tentative Parcel Map
• On-site Storage Zoning Ordinance Amendment

5 Accepted status reports on the following topics/projects Reviewed potential amendments to the Zoning Ordinance intended to improve consistency with State law, clarify development standards, and address implementation issues identified by staff. • 2023 Zoning Code Update Study Session
• ADU Ordinance Amendment Study Session
• Short-Term Rental Ordinance Study Session
Processed Appeals of Discretionary Land Use Applications for the following projects Not applicable. No appeals were filed for Planning Commission review.

Approved Development Projects
The Planning Commission continued to review and take action on discretionary development applications throughout the fiscal year.

Applications reviewed included:
• Major Design Review (2 Projects)
• Demolition (3 Projects)
• Conditional Use Permits/ Amendments (2 Projects)
• Tentative Subdivision Map (3 Projects)
• Major Sign Permit (4 Projects)
Received Informational Training Sessions from the following Agencies Not applicable. It is the goal of the Community Development Department to provide trainings to the Planning Commission on topics of interest every other year, depending on the availability of requisite outside staff or agency participation and Department workload.

City of St. Helena
Community Development Department
1088 College Avenue
St. Helena, CA 94574
CITY OF ST. HELENA
Planning Commission
Work Plan for Fiscal Year 2026-2027
(July 1, 2026 – June 30, 2027)
&
Accomplishments for Fiscal Year 2025-2026
(July 1, 2025 – June 30, 2026)
Commissioners:

Christopher Warner, Chairperson
Sue Frudek, Vice Chairperson
Autumn Anderson
Michelle Covell
Hector Lopez
Planning Commission Secretary:

Leza Mikhail – Director of Community Development

2 MISSION STATEMENT
The City of St. Helena Planning Commission is a five-member body of community representatives appointed by the City Council. The goal of the Planning Commission is to guide land use and development decisions that implement the City's General Plan, preserve the unique character of St.

Helena, promote housing opportunities, protect community resources, and ensure that growth occurs in a manner that benefits current and future residents.

PLANNING COMMISSION ROLES & RESPONSIBILITIES
Pursuant to Chapter 2.60 of the St. Helena Municipal Code, the Planning Commission serves as the City's advisory body on planning and development matters and is responsible for carrying out duties delegated by the City Council and Municipal Code.

The Planning Commission's primary responsibilities include:
• Reviewing and acting upon development applications as authorized by the Municipal Code. • Conducting public hearings on land use and development matters. • Making recommendations to the City Council regarding amendments to the General Plan, Housing Element, Zoning Ordinance, and other planning-related policies. • Reviewing environmental documents prepared pursuant to the California Environmental Quality Act (CEQA).
• Evaluating development proposals for consistency with adopted City plans, policies, and regulations.
• Providing opportunities for public participation in planning and land use decisions. • Assisting with implementation of State housing laws and local planning initiatives.

FY 2026-27 WORK PLAN
The FY 2026-27 Planning Commission Work Plan should provide the goals/objectives (no more than five) of the workplan, the activities to accomplish the goals, the priority ranking of each goal, and where feasible the timeline anticipated to accomplish the goal.

1. Schedule, notice, and conduct bi-monthly meetings (usually held on the 1st and 3rd Tuesday of each month) for the purpose of carrying out the roles and responsibilities described within this work plan. (Ongoing)

2. Conduct workshops and public hearings, open to the public for the purpose of studying, evaluating, and facilitating decision-making regarding items scheduled for public hearings, or with relevance to land use. Public hearings serve to process certain permit types or legislative actions that require Planning Commission consideration, and workshops serve to educate the Planning Commissioners and members of the public about City planning policies, legal requirements, department procedures, work programs, and other general topics of interest. The

3 types of workshops and public hearing projects/legislative topics that are anticipated to be considered for the FY 2026-27 year are listed below:
o The Department has a general list of anticipated land use application projects/ entitlements, ordinance amendments, and policy documents that may be presented to the Planning Commission during the 2026 - 2027 fiscal year, which includes, but is not limited to, the following projects:
• Alilia Hotel Expansion
• 1360 Main Street Redevelopment
• Adams Street Castellucci Hotel
• Spring Vineyard Housing Project Appeal
• Zoning Ordinance Amendments
- ADU Ordinance Update
- Short-Term Rental Ordinance Update
- Sign Ordinance Update
- Miscellaneous Code Update 1
• Inclusionary Housing Ordinance Review and Potential Update • General Plan Annual Review
• Housing Strategy
• Review and Update of the Planning Commission By-Laws
• Review elements of the Zoning Ordinance to streamline and promote economic development
• Review of subjective and objective sections of the ordinance as determined necessary
o Outside of regularly scheduled public hearing items or projects established by the Community Development Department or by referral by the City Council, workshops for the 2026 - 2027 fiscal year that fall under the purview of the Planning Commission may include the following topics (dependent on Department workload and capacity) suggested throughout the fiscal year, listed in order of priority:
• Brown Act and Robert's Rules of Order (TBD - As necessary) • Role of a Planning Commissioner (TBD – As necessary)
• Developing Findings, Conditions of Approval and Mitigation Measures (TBD – As necessary)
• Architectural Plan Review / Design Review Guidelines (TBD – As necessary) • City’s Communications, Engagement Programs and Tools (TBD) • Capital Improvement Plans and Planning Commission Role (TBD) • California Environmental Quality Act and State Legislative Updates (TBD - As necessary)

4 - Permit Streamlining Act (TBD - As necessary)
• City’s Communications, Engagement Programs and Tools (TBD) • Capital Improvement Plans and Planning Commission Role (TBD) o In addition to the workshop items identified above that fall under the direct purview of the Planning Commission and/or are on the Community Development Department workplan, the following informational/educational workshops are of interest to the Planning Commission. These workshops fall under the purview and/or workplans of other City Departments, outside agencies, or are outside of the Planning Commission purview, and may be scheduled, depending on the availability of requisite outside staff or agency participation:
• Napa County Office of Emergency Services
- Hazard Mitigation Plan Informational Presentation
• St. Helena Evacuation Plan / Wildfire Considerations / Notification Overview • Napa County Regional Climate Action & Adaptation Plan (RCAAP) • Napa Countywide Transportation Plan & Active Transportation Plan • Housing Element and RHNA Implementation
• Napa Local Agency Formation Commission (LAFCO)
• Napa Valley Vine Trail Planning and Implementation
• Our Town St Helena
• Chamber of Commerce & Napa Valley Tourism Corporation (NVTC)

3. Attend the League of California Cities Planning Commissioners Academy (Spring 2027) FY 2025-26 ACCOMPLISHMENTS
During FY 2025-26, the Planning Commission continued to advance City Council priorities, review development applications, and provide policy guidance on a variety of planning matters.

Recommendations to City Council
The Planning Commission reviewed and provided recommendations on the following policy and legislative matters:
• 1030 Fulton Lane General Plan Amendment
• Vision Triangle Zoning Ordinance Amendment
• Calculation of Floor Area Zoning Ordinance Amendment
• Short-Term Rental Zoning Ordinance Amendment
• Alcohol Sales Zoning Ordinance Amendment
• Spring Grove Tentative Subdivision Map
• Sylvaner Tentative Parcel Map
• Kidd Ranch Tentative Parcel Map
• On-site Storage Zoning Ordinance Amendment

5 Accepted status reports on the following topics/projects Reviewed potential amendments to the Zoning Ordinance intended to improve consistency with State law, clarify development standards, and address implementation issues identified by staff. • 2023 Zoning Code Update Study Session
• ADU Ordinance Amendment Study Session
• Short-Term Rental Ordinance Study Session
Processed Appeals of Discretionary Land Use Applications for the following projects Not applicable. No appeals were filed for Planning Commission review.

Approved Development Projects
The Planning Commission continued to review and take action on discretionary development applications throughout the fiscal year.

Applications reviewed included:
• Major Design Review (2 Projects)
• Demolition (3 Projects)
• Conditional Use Permits/ Amendments (2 Projects)
• Tentative Subdivision Map (3 Projects)
• Major Sign Permit (4 Projects)
Received Informational Training Sessions from the following Agencies Not applicable. It is the goal of the Community Development Department to provide trainings to the Planning Commission on topics of interest every other year, depending on the availability of requisite outside staff or agency participation and Department workload.

Agenda Report to the City Council
Agenda Section: CONSENT ITEMS
Department: Public Works Department
DATE: October 13, 2026
FROM: Bruce Zaeni, Project Manager, Joseph Leach, Director of Public Works
SUBJECT: Consideration and Proposed Approval of a Resolution Authorizing execution of a Professional Services Agreement with Hydrologics, Inc. as a sole source vendor, to flush and clean the City’s water main distribution system and conduct video inspection of approximately 10 percent of the system for an Amount Not-ToExceed $917,072 and related budget amendment.

RECOMMENDED
ACTION:

Adopt Resolution.

PREVIOUS COUNCIL
ACTION:

On March 24, 2026, the City Council adopted Resolution No. 2026-034 authorizing the creation of Capital Improvement Plan Project No. W26-04 Water Main Pipeline Cleaning Program with an initial budget of $150,000 for Construction and $2,000 for CIP Overheads (i.e. staff time).

STATEMENT OF THE
PURPOSE:

Authorize negotiation and execution of a Professional Services Agreement with Hydrologics, Inc. as a sole source vendor, to assist the public works department with their patented, industryleading Zero-Discharge Flushing (ZDF) to flush and clean the City’s water pipeline distribution system and conduct video inspection of approximately 10 percent of system and authorize the related budget amendment.

FINANCIAL IMPACT: This action requires a budget amendment to CIP No. W26-04 Watermain Pipeline Cleaning Program. As described below, additional funding of $866,719 for Construction and $18,457 for CIP Overheads (i.e. staff time) totaling $885,176 is necessary to deliver this critical project. While sufficient funding is available through Water Bond proceeds, staff will present an updated Water Bond expenditure strategy at the Council meeting wherein the updated Capital Improvement Program is considered for adoption.

CEQA DETERMINATION: Statutory Exemption

BACKGROUND:

The water quality issue has been at the forefront in the City for a while and the Public Works Department has been investigating the potential sources and causes of brown water occurrences. The staff believes the build-up of minerals such as manganese and iron in the water distribution system to be a significant cause. Flushing improves water quality and production service for customers by removing sediment and biofilm in the form of naturally occurring minerals in the water.

In June of this year, the City undertook a limited pilot cleaning project using the services of Hydrologics, Inc., which was successful in removing substantial amounts of minerals from the pilot area. Based on the positive results of that pilot flushing exercise, the Public Works Department is now requesting the Council to approve Hydrologics, Inc. as the sole source vendor for the next phase of the flushing program, which will include the majority of the Cityowned water main distribution system sizes 4 to 14 inches. This limitation is due to the required flow velocity needed for the Zero Discharge Flushing (ZDF) method to be effective.

Hydrologics, Inc. developed and patented an industry-leading water main flushing technology known as ZDF. A truck with a series of filters and pumping equipment connects two hydrants within the distribution system. Water is then pumped through a section of main between those hydrants, filtered, monitored, and then reintroduced into the distribution system. There is no water lost as would be with conventional flushing, so this method allows a quantifiable amount of water to be saved while effectively conducting routine flushing. With assistance from Public Works staff, distribution valves are manipulated to perform cleaning of several miles of distribution mainly from a single location, increasing efficiency and productivity. All equipment on the truck is NSF certified for safe use in drinking water. ZDF is a sole-sourced patented technology.

In addition, Hydrologics, Inc. will utilize their specialized video camera equipment and crews to inspect approximately 10 percent of the system being flushed to provide a visual record of preand post-flushing conditions. As with ZDF process, the video inspection is dependent on the availability of connections (e.g. hydrants), and the distances between those connection points for accessibility.

DISCUSSION:

To improve the water quality in the City’s distribution system, thorough cleaning of the pipes is recommended based on the City’s successful pilot ZDF flushing of approximately seven miles of water pipes over the summer. Since normal flushing of the fire hydrants by City staff does not generate as much water flow velocity, the more rigorous method provided by ZDF technology is recommended to dislodge and filter the mineral built up in the pipes.

Hydrologics, Inc. pioneered ZDF, the only water main flushing process that cleans distribution mains, enhances water quality, and eliminates waste. Unlike conventional hydrant flushing, ZDF circulates water through a closed-loop system between hydrants. High-velocity flow at 5 feet per second scours the pipe interior, removing accumulated sediment and biofilm, while filtration within their equipment cleans the water to one micron before it is returned to the distribution system.

The Hydrologics proposal includes the following:
• Flushing operations of approximately 40+ miles of distribution pipelines. (approximately 89% of the total system).
• Pre- and post-flushing CCTV of approximately 4+ miles of select distribution pipelines. • Complete flushing/CCTV work in 47 working days (i.e. approximately 2.5 months), commencing in late October 2026.
• Proposal includes a negotiated discount of $92,120.

The City initially sought a CCTV proposal for the entire distribution system, Hydrologics noted that none of their clients sought such an extensive (i.e. costly) service. Most agencies, they noted, found that pre- and post-flushing camera inspection of 10% of the system provided a sufficient representative sample of the flushing effectiveness.

Next Steps
Develop pre- & post-flushing CCTV locations — Based upon the available data (i.e.

Grapevine reports, GIS pipe material/diameter data, pressure zones, etc.), staff will develop the specific line segments to perform the CCTV work.

Public Outreach — City staff will provide a schedule, area map and information materials (i.e. website, social media, direct email, door hangers, etc.) to notify customers in advance of, during and after flushing activities have been performed. Additionally, the materials will provide recommended actions customers should take "post flushing" to mitigate remaining discolored water.

Water Treatment Plant Transmission Main CCTV evaluation — receipt of the video inspection of select locations of the 24-inch transmission main is expected to be received by the end of October. It is expected that the videos will provide the disposition of any debris within those locations.

WTP Transmission Main Cleaning — staff is engaging several vendors to provide proposals to clean this pipeline (ranging from 24 to 14 inches in diameter) from the WTP to the "tee" on Pratt Avenue, approximately 3.1 miles.

CCTV Evaluation — Staff will retain a professional to evaluate the 4+ miles of video footage to develop a phased implementation strategy/budget for rehabilitation (e.g. replace, lining, etc.).

Proposed Finances
The total compensation for the flushing effort and partial system video inspection shall not exceed $917,072. Below represents the budget amendment necessary to deliver this project:

The previous "Total Expended/Encumbered" scope includes the pilot flushing program performed in June 2026 and a Purchase Order issued to Hydrologics for the CCTV work on

the Water Treatment Plant Transmission Main (i.e. primarily low points in the system to be accessed via hydrants).

ENVIRONMENTAL REVIEW:

Statutory Exemption
GOAL:

Goal 2: Improve Infrastructure & Further Environmental Sustainability Goal 5: Enhance Quality of Life
ATTACHMENTS:

1. Resolution - Award PSA for Flushing Services Hydrologics v1

2. PSA Hydrologics System Wide ZDF & Video Inspection

3. Public Comment - Joshua Parke

CITY OF ST. HELENA
RESOLUTION NO. 2026-____

RESOLUTION AUTHORIZING THE CITY

MANAGER TO NEGOTIATE AND EXECUTE A

PROFESSIONAL SERVICES AGREEMENT
WITH HYDROLOGICS, INC. FOR WATER MAIN

CLEANING SERVICES AND PARTIAL VIDEO
INSPECTION, CIP NO. W26-04 IN AN AMOUNT
NOT-TO-EXCEED $917,072 AND APPLICABLE

BUDGET AMENDMENT

RECITALS
A. The City of St. Helena has experienced brown water occurrences in its water distribution system attributable to the buildup of minerals including manganese and iron. The public works department has been investigating the potential sources and causes of brown water occurrences; and
B. Staff believe the build-up of minerals such as manganese and iron in the water distribution system to be the main cause of the issue; and
C. Staff believe flushing will improve water quality for residents by removing sediment and biofilm from naturally occurring minerals in the water; and
D. Hydrologics, Inc., was successful in removing substantial amounts of minerals from the pilot project area in the city; and
E. Based on the positive results of the pilot flushing exercise conducted in June 2026, public works department is now
requesting the council approve Hydrologics, Inc. as the sole source vendor to flush the majority of city owned water system; and
F. Hydrologics, Inc. will also utilize their specialized video camera equipment and crews to inspect approximately 10
percent of the system being flushed to provide visual record of pre and post flushing conditions.

G. Hydrologics, Inc., has extensive and successful background in providing water agencies and municipalities with Zero Discharge Flushing (ZDF) services; and
H. Funding is available to cover the cost of these services and city’s staffing support.

RESOLUTION
NOW, THEREFORE, the City Council of the City of St. Helena resolves as follows:

1. Authorizes the City Manager to execute a Professional Services Agreement with Hydrologics, Inc. for CIP No. W26-04 in an amount not-to-exceed $917,072.

2. Funding for this proposed agreement is available within the FY2026-27 Capital Improvement Program for Project CIP No.

W26-04 and funded by Water Bond.

3. A budget amendment is necessary to support this critical project:

Approved at a Regular Meeting of the St. Helena City Council on October 13, 2026, by the following vote:

Mayor Dohring:

Vice Mayor Deasy:

Council Member Barak:

Council Member Spadarotto:

Council Member Diaz:

APPROVED: ATTEST:

Paul Jamison Dohring, Mayor Andrew Bradley, City Clerk

Hydrologics, Inc. System Wide Zero Discharge Flushing & Water System Video Inspection
1 CITY OF ST. HELENA

PROFESSIONAL SERVICES AGREEMENT
System Wide Zero Discharge Flushing & Water System Video Inspection Services This Agreement is made and entered into as of October 13, 2026, by and between the City of St. Helena, a public agency organized and operating under the laws of the State of California (“City”), and Hydrologics, Inc. a corporation with its principal place of business at 500 S Australian Ave, Ste 600-1008, West Palm Beach, Forida, 33401 (hereinafter referred to as “Consultant”). City and Consultant are sometimes individually referred to as “Party” and collectively as “Parties” in this Agreement.

RECITALS
A. City is a public agency of the State of California and is in need of professional services for the following project:

System Wide Zero Discharge Flushing and Water System Video Inspection Services (hereinafter referred to as “the Project”).

B. Consultant is duly licensed and has the necessary qualifications to provide such services.

C. The Parties desire by this Agreement to establish the terms for City to retain Consultant to provide the services described herein.

AGREEMENT
NOW, THEREFORE, IT IS AGREED AS FOLLOWS:

1. Services.

Consultant shall provide the City with the services described in the Scope of Services attached hereto as Exhibit “A.”

2. Compensation.
a. Subject to paragraph 2(b) below, the City shall pay for such services in accordance with the Schedule of Charges set forth in Exhibit “A”. b. In no event shall the total amount paid for services rendered by Consultant under this Agreement exceed the sum of $917,072. This amount is to cover all printing and related costs, and the City will not pay any additional fees for printing expenses. Periodic payments shall be made within 30 days of receipt of an invoice which includes a detailed description of the work performed. Payments to Consultant for work performed will be made on a monthly billing basis.

3. Additional Work.