Site Mitigation & Restoration Program

We protect and maintain California’s land and places
by setting strict standards for land restoration and cleanup

Archived Brownfields News

January 14, 2021

We are currently soliciting INNOVATIVE IDEAS and APPLICATIONS for the TSI+ Program

Since 2004, the TSI Program has provided environmental services to local governments, school districts, and nonprofits to facilitate the return of brownfields to safe and productive uses. DTSC has provided assessment, investigation, and cleanup planning services to over 100 projects, in 68 cities, and 30 counties, throughout the State of California. Take a look at our short video, Using Loose Change for Big Changes for Brownfields in California (link opens new window) for highlights of our TSI work. Building on the success of the TSI Program, DTSC envisions an enhanced TSI+ Program to better facilitate development of brownfields to support disadvantaged California communities. DTSC is looking to align brownfield redevelopment efforts with California’s priorities of “tackling our state’s affordability crisis, creating inclusive economic grown and opportunity for every child, and standing up for California values – from civil rights, to immigration, environmental protection, access to quality schools at all levels, and justice” (see Governor Newsom’s website (link opens new window)). DTSC will explore and experiment with different approaches to focus on brownfields with proposed redevelopment intended to support communities that are disadvantaged, have environmental justice issues, or are disproportionately burdened by and vulnerable to multiple sources of pollution. To learn more, visit our Loans and Grants page. For more detailed discussion and to obtain a copy of the TSI+ application, contact

November 23, 2020

California-based Attenuation Factor for Vapor Intrusion Sites

Many of us in the regulatory, development, and municipal communities have experienced the challenges of addressing volatile organic chemical contamination when we recycle contaminated land for housing and commercial uses. The potential risk posed by harmful vapors in breathing spaces, also known as vapor intrusion, is a challenge to redevelopment, particularly because it adds a high level of uncertainty to the decision making process. The Department of Toxic Substances Control is pleased to be able to share a preview of the process that has been used to derive a potential California-based attenuation factor for vapor intrusion calculations. The study, when complete, will provide the redevelopment sector with an additional tool to facilitate the land revitalization process. Although the study is under peer review and the report is not ready for release, DTSC is providing an overview of the data and process utilized for the calculations. Please e-mail for a copy of the presentation made at the California Land Recycling Conference 2020 – Communities Rising.

DTSC’s Voluntary Agreements - Assessment & Cleanup Process Diagram

Download PDF version of this diagram.

This document is intended to be guidance only and it does not supersede or implement laws or regulations. The information in this advisory is intended solely as guidance and as educational reference material and should not be considered enforceable or regulatory in nature.