Join Tri-Valley CAREs on Thursday, October 22, 2026, from 5:30 to 6:30 p.m. for a neighborhood walking tour exploring the history of groundwater contamination and cleanup near Lawrence Livermore National Laboratory. We will meet at the Susan Lane cul-de-sac in Livermore and walk approximately half a mile from the Lab’s perimeter along the Arroyo Seco path.
The walk will follow the area above the off-site groundwater plume and explain its history, how it was remediated, and the role local residents and Tri-Valley CAREs played in the cleanup. We will also discuss ongoing contamination inside the Lab and how it relates to the surrounding community.
Groundwater contamination can be difficult to understand from a report or a map. Groundwater sits below the surface, within spaces in soil and rock. A “plume” describes an area of groundwater containing contaminants that have spread from their source. On this walk, we will connect that underground history to places people can see along the route.
For residents who use the Arroyo Seco path or live nearby, the tour offers a chance to learn about the cleanup history of a familiar part of Livermore. We will discuss how contamination extended beyond the Lab’s boundary and what happened to address it. The history of the off-site plume matters even after remediation: it helps explain why cleanup and public oversight became lasting concerns for this neighborhood.
We will also discuss the difference between the remediation of this off-site plume and the contamination that remains on-site. LLNL’s environmental restoration program addresses soil and groundwater affected by past activities at the facility. The walk will provide context for understanding that work and why Tri-Valley CAREs continues to follow the Lab’s cleanup.
Local residents and Tri-Valley CAREs have a place in this history. The tour will include their role in the groundwater cleanup and the community’s efforts to understand what was happening beneath the neighborhood. Residents deserve clear information about contamination near their homes and a meaningful opportunity to take part in decisions that affect their community.
The walk will give us time to discuss that history together. Bring your questions about the plume’s remediation, the ongoing on-site cleanup, or the community’s involvement. If you remember earlier stages of the cleanup or have lived in the neighborhood for many years, we welcome your perspective.
You do not need a technical background to attend. We invite neighbors, people who regularly use the Arroyo Seco path, and anyone interested in learning more about Livermore’s environmental history. Please share this invitation with someone who would like to understand the cleanup work near the Lab.
Tour details
- Date: Thursday, October 22, 2026
- Time: 5:30-6:30 p.m.
- Meeting point: Susan Lane cul-de-sac, Livermore
- Route: Approximately 0.5 miles, from the Lab’s perimeter along the Arroyo Seco path
- To join: Email Anoushka at anoushka@trivalleycares.org.
Wear comfortable walking shoes and bring water. If you have questions about the route or accessibility, please contact Anoushka before the event.
We hope to see you on October 22.