Toxic vapors in indoor air can come from multiple sources – underground contamination, consumer products or outdoor air. Vapors can travel between soil particles and reach ground surface.
Vapor Intrusion Information
February 2020 Draft Supplemental Guidance
The Public Draft Supplemental Guidance: Screening and Evaluating Vapor Intrusion is available for review and public comment until 12:00 noon, April 30, 2020. See public notice for available public meetings.
Hard Copy Locations
Hard copies are available for review at locations listed below. Please call the contact person to schedule an appointment.
1001 I Street, Sacramento, CA
Contact Abe Waggoner, (916) 341-5895
North Coast Regional Water Board Office
5550 Skylane Building, Suite A, Santa Rosa, CA
Contact: Paul Nelson, (707) 576-2686
Central Valley Regional Water Board Office
1685 E. Street, Fresno, CA
Contact: Christine Hernandez, (559) 445-6542
San Francisco Bay Regional Water Board Office
1515 Clay Street, #1400, Oakland, CA
Contact: Melinda Wong, (510) 622-2430
Lahontan Regional Water Board Office (South Lake Tahoe)
2501 Lake Tahoe Blvd., South Lake Tahoe, CA
Contact: Jeff Brooks, (530) 542-5420
Lahontan Regional Water Board Office (Victorville)
15095 Amargosa Road, Bldg. 2, Suite 210, Victorville, CA
Contact: Alonzo Poach, (760) 241-7365
Los Angeles Regional Water Board Office
320 W. 4th Street, Suite 200, Los Angeles, CA
Contact: Lucinda (Cindy) Flores, (213) 576-6633
Santa Ana Regional Water Board Office
3737 Main Street, Suite 500, Riverside, CA
Contact: Lenore Gamez, (951) 782-4905
San Diego Regional Water Board Office
2375 Northside Drive, Suite 100, San Diego, CA
Contact: Records Request Hotline, (619) 516-1990
Department of Toxic Substances Control Regional Office
5796 Corporate Avenue, Cypress, CA
Contact: Jone Barrio, (714) 484-5336
Department of Toxic Substances Control Regional Office
9211 Oakdale Avenue, Chatsworth, CA
Contact: Robert Hardison, (818) 717-6521
Technical Aspects of Vapor Intrusion and Supplemental Guidance
1:00 PM – 3:00 PM: Presentation
3:00 PM – 4:30 PM: Questions and Answers
Overview on Vapor Intrusion and Supplemental Guidance
(General Public Content)
6:00 PM – 7:00 PM: Presentation
7:00 PM – 8:00 PM: Questions and Answers
Participants will have opportunities for questions and answers and to provide comments.
* To request language services, please contact Marina Pérez at (916) 322-4265 at least 10 business days prior to the meeting.
* If you need sign language services in your language, please contact Moises Morena-Rivera at (916) 341-5261 at least 10 business days prior to the meeting.
April 1, 2020 – 1:00 PM and 6:00 PM
CalEPA Headquarters – Sierra Room
1001 I Street, Sacramento, CA 95814
** This meeting will also be webcast at: https://video.calepa.ca.gov/
Questions may be submitted to: DWQ-DWQemail@example.com during the meeting. Please add “Meeting Question” to subject line.
April 9, 2020 – 1:00 PM and 6:00 PM
Online Webinar: https://meet.lync.com/cawaterboards/steven.mcmasters/6ZNZ700B;
Call-In Number: (916) 562-0861; participant passcode: 779621632
This webinar uses Microsoft™ Skype, which participants will need to view presentations.
Microsoft™ Skype is free and can be downloaded at: https://www.skype.com/en/get-skype/
Questions may be submitted to: DWQfirstname.lastname@example.org during the webinar. Please add “Webinar Question” to subject line.
April 14, 2020 – 1:00 PM and 6:00 PM
San Diego Regional Water Quality Control Board, Hearing Room
2375 Northside Drive, Suite 100, San Diego, CA 92108
April 16, 2020 – 1:00 PM and 6:00 PM
City of Commerce Council Chambers
2535 Commerce Way, Commerce, CA 90040
* For questions regarding the public meetings, please contact Abe Waggoner at (916) 341-5895 or DWQ-DWQemail@example.com
Public Comment due 12:00 noon, April 30, 2020
Written comments on February 2020 Public Draft Supplemental Guidance must be submitted by 12:00 noon, April 30, 2020 by mail or email.
Methods to Submit Comments
See Comment Submission Instructions for details.
To help the CAlEPA Vapor Intrusion Workgroup to organize comments, please use one of the designated comment forms and electronically submit your comments to the email provided below. The work group offers Comment Form A (Adobe® Version) and Comment Form B (Microsoft® Word Version). Alternatively, you may also submit your comments in a letter (or email) drafted in the official format of your agency or company, or in a format of your choosing.
Below are the available methods (use one):
- Comment Form A (Adobe® Version) English Version
- Comment Form A (Adobe® Version) Spanish Version
- Comment Form B (Microsoft® Word Version) English Version
- Comment Form B (Microsoft® Word Version) Spanish Version
How to Submit Comments:
- Email: DWQfirstname.lastname@example.org
(please add “Comment Submittal” to subject line)
- Mail: State Water Resources Control Board, Division of Water Quality
CalEPA VI Workgroup, Attention: Abe Waggoner
1001 I Street, 15th Floor, Sacramento, CA 95814
Note on Response to Comment
Please Note: The Vapor Intrusion Work Group will group and categorize comments and prepare responses. Responses to individual comments will not be provided.
What are vapor-forming chemicals?
Vapor-forming chemicals can easily move into the air and form vapors. Common ones include solvents used in dry cleaning, degreasing, gasoline and diesel fuel. Examples of toxic vapor-forming chemicals are:
- Tetrachloroethylene, also called perchloroethylene (“perc” or PCE): PCE is known to the State of California to cause cancer. Many dry cleaners have used PCE for decades, but this use will be phased out by 2023.
- Trichloroethylene (TCE): TCE is known to the State of California to cause cancer and harm reproductive health. TCE is commonly used in industries to remove oil or grease. It’s also in some household products such as stain removers and adhesives.
- Naphthalene: Naphthalene is known to the State of California to cause cancer. Sources include inks, dyes, fossil fuels, mothballs, tar, tobacco smoke, and burning of wood.
What are other sources of vapor-forming chemicals?
Many consumer products, such as household cleaners, furniture, adhesives and paints, contain these chemicals and can pollute indoor air. Vapor-forming chemicals in outdoor air can also enter buildings.
Vapor Intrusion and Your Health Fact Sheet
California Vapor Intrusion GeoTracker Database
Vapor Intrusion is a complex, highly variable science. A robust empirical dataset is needed to help us better understand vapor behavior.
This document provides instruction on how to input relevant vapor intrusion information used in a vapor intrusion assessment into the GeoTracker database.
ESI Information Page
GeoTracker Help Desk
State Water Resources Control Board
Vapor Intrusion Webpage Links:
- DTSC Site Mitigation and Restoration Program Vapor Intrusion
- DTSC Human Health Risk (HERO)
- USEPA Vapor Intrusion
- ITRC – Vapor Intrusion Documents
Existing Vapor Intrusion Guidance Document Links:
- OSWER Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway from Subsurface Vapor Sources to Indoor Air (2015)
- Advisory – Active Soil Gas Investigations (July 2015)
- Interim Framework for Assessment of Vapor Intrusion at TCE-Contaminated Sites in the San Francisco Bay Region (2014)
- Final Guidance for the Evaluation & Mitigation of Subsurface Vapor Intrusion to Indoor Air (2011)
*Please note this is not the complete list of existing vapor intrusion guidance documents.
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- New! April 2020 Public Meetings:
- April 1, 2020 – CalEPA Headquarters
- April 9, 2020 – Webinar
- April 14, 2020 - San Diego Regional Water Quality Control Board
- April 16, 2020 – City of Commerce Council Chambers
* Please see Public Notice for more details