Mill Valley School District

AT A GLANCE

Draft EIR – Public Comment Period: September 2 – October 17, 2025
The Draft Environmental Impact Report (EIR) for the Mill Valley Middle School Modernization Project is now available for public review and comment until 5 p.m. on October 17. 

PEA Report – Public Comment Planned for October 2025
The District is completing additional environmental testing at the request of the regulatory agencies providing project oversight. A Revised PEA Report will be submitted in October and released for public comment at the same time.

Key documents associated with the modernization project are available below and on the DTSC’s Envirostor webpage for review. 

• Draft EIR
• Draft EIR Chapter References
• Draft EIR Appendices
• Draft PEA 
• NOA
• NOC

Modernization Project Overview 
The Mill Valley School District (MVSD) is investing Measure G bond funding to modernize our school facilities. These upgrades are designed to meet today’s educational, safety, security, and accessibility standards. A major part of this effort is the Mill Valley Middle School (MVMS) Modernization Project, which aims to provide a middle school environment that supports next-generation learning.

MVMS Modernization Draft EIR 
The Draft EIR is available for public comment from September 2 to October 17, 2025.  The Draft EIR evaluates a wide range of options for the MVMS project. While the proposed project is to build a brand-new school, rising geotechnical and soil disposal costs will exceed the current budget.

MVSD remains committed to a fiscally responsible approach, funding the modernization project without additional financing, while still delivering a state-of-the-art facility for students and the community.

The District is now focusing on two alternatives that can be completed within the current budget:

1. Renovate the Existing MVMS Campus (Sycamore Drive) - This option would modernize the current middle school campus through interior and exterior building upgrades, landscaping improvements, and a possible new STEM classroom building.  The result would be a significantly improved campus with the look and feel of a new school.

2. Build a New Middle School at 70 Lomita Avenue (formerly Terra Marin) - This option would construct a brand-new middle school co-located with Edna Maguire Elementary. 

Both alternatives would upgrade facilities to modern safety, security, and accessibility standards, enhance STEM learning opportunities and replace outdated infrastructure.

Additionally, the Board is assessing housing students at a temporary campus at 70 Lomita Avenue during the two-year construction period as another cost-saving measure.

MVSD recognizes that both alternatives (construction of a brand-new middle school and temporary campus) at the 70 Lomita Avenue site could affect the surrounding community. The District is committed to working closely with residents, families and local partners to develop strategies that help minimize potential impacts.

The Board of Trustees will consider the EIR, public input, and its own criteria – including cost, feasibility and educational programming – to determine the most appropriate location for the middle school. The Board of Trustees is expected to select a preferred alternative in December 2025, which would allow construction to begin as early as June 2026.

How to Comment on the Draft EIR

The District invites community input on the Draft EIR. The Board of Trustees will consider all public comments—along with cost, feasibility, and educational priorities—when selecting the alternatives that best serve students, staff, and the community.

Ways to Participate

• Review the Draft EIR:
• Submit Written Comments:
  • By Email: jarroyo@mvschools.org
  • By Mail:
    Mill Valley School District
    Attn: Julio Arroyo, Director of Maintenance and Operations
    411 Sycamore Avenue
    Mill Valley, CA 94941
• Attend the MVSD Board Meeting: Share your comments on the Draft EIR in person at the MVSD Board of Trustees meeting on September 10, 2025, at 5:00 p.m. at the Mill Valley Middle School Library, 425 Sycamore Avenue, Mill Valley.

Comment Period: September 2 – October 17, 2025

Preliminary Endangerment Assessment (PEA)
The Mill Valley Middle School campus sits on land that once served as a municipal landfill, where waste was buried or burned from the early 1900s until the 1950s. Before the school was built in 1969, the site was covered with a layer of sandy clay to prevent contact with the waste below.

To address any historical environmental concerns, the MVSD is conducting a Preliminary Endangerment Assessment (PEA) under the oversight of the California Department of Toxic Substances Control (DTSC) and Marin County Environmental Health. DTSC’s Brownfields School Evaluation Branch specializes in making sure school properties with a history of contamination are properly cleaned up or mitigated to protect students and staff.

What the PEA Does
The PEA looks at past environmental conditions to determine if the site is safe for today’s use and any future redevelopment. A central part of the process is the Human Health Risk Assessment, which examines whether chemicals or contaminants at the school could pose health risks to students or staff.

Agency Comments on the Draft PEA 
MVSD submitted a draft PEA earlier this year. After reviewing it, DTSC and Marin County requested additional testing and refinements. The District is now preparing a Revised PEA that will incorporate these comments and additional data, and it will be released for public review in October.

• Methane Monitoring: Marin County requested additional methane monitors at the current campus. The methane monitors are now installed in all school buildings and lower-level classrooms. No exceedances have been detected.
• Soil and Vapor Testing: DTSC asked for more soil sampling in landscaped areas and a new risk assessment using updated soil vapor data. Soil vapor samples taken in July 2025, under conservative conditions, confirmed earlier findings:
  • Students: No health hazard or incremental cancer risk under typical use (six hours per day, 180 days per year, for three years).
  • Teachers/Staff: No immediate health hazard. A slightly elevated lifetime cancer risk was calculated (four in one million), which falls within DTSC’s acceptable risk management range. This calculation uses a conservative exposure scenario of eight hours per day, 250 days per year for 25 years.

These results reaffirm that current campus conditions do not present an immediate risk to students or staff.

Next Steps in PEA Process
During August and September, additional work will be performed to better understand site conditions and to inform future mitigation measures to ensure long-term protection of students, staff, and the environment if the campus is redeveloped. 

• MVSD will collect sub-slab soil vapor samples beneath school buildings in August and September to check whether vapors could pose a risk of entering classrooms (a process called vapor intrusion).

• If needed based on the sub-slab sample results, indoor air will also be tested.
• Additional surface soil sampling in landscaped areas will be completed in September.

All new data will be included in the Revised PEA, which will be submitted to DTSC and Marin County for review and made available for public comment in October.

Modernization Project Schedule

Please refer to the table below for details on the current schedule.

Mailing list

To be added to the project mailing list, request a briefing for your organization, or ask a question, please email us at: info@mvmsmod.com.  

Project Documents

Key documents associated with the modernization project are available below and on the DTSC’s Envirostor webpage for review. 

• Draft EIR
• Draft EIR Appendices
• Draft EIR Chapter References
• Draft PEA 
• NOA
• NOC