Background

The South Coast AQMD has received numerous odor complaints from the Seal Beach, Huntington Beach, and Long Beach areas in the past two years related to a gas/sulfur/chemical type smell.  During these events, the odors are reported to originate along the shoreline and quickly travel through the neighboring cities, eventually dissipating.  Long Beach, Huntington Beach, and Seal Beach fire departments have also reported that their 911 emergency phone lines receive numerous calls for emergency service reporting natural gas leaks during these odor events, prompting them to ask for assistance from the South Coast AQMD in locating the source.  To date, the source(s) of the odors have not been clearly identified but potential sources are being investigated.  There are multiple sources within the area that have the potential to emit gas/sulfur/chemical type odors, and due to the intermittent nature and unknown source location, it is challenging to assess the cause. 

Additional Information

• News Release (PDF) - South Coast AQMD Issues Violation to Oil Tanker Ship for Fugitive Emissions - Nov. 9, 2018
• Fact Sheet (PDF) - "FAQ on the Coastal Offshore Odor Investigation and Health Effects"
  These frequently asked questions describe the air sampling results and address key questions about the health effects of the measured pollutants.

Complaint Investigations

South Coast AQMD has responded to the odor complaints along the shoreline by deploying Compliance staff to investigate.  In most cases, the odors have already dissipated by the time they reach the area.  As part of the ongoing investigation into these odors, South Coast AQMD has taken the following actions:

• Responded to and investigated all odor complaints near the shoreline area and performed odor surveillance in the surrounding affected coastal communities of Long Beach, Seal Beach, and Huntington Beach (the shoreline complaint area is identified in the yellow highlighted area in the map below). 

• Enlisted the assistance of the Long Beach, Huntington Beach, and Seal Beach Fire Departments

• Requested assistance from city, state, and federal agencies to aid in the investigation of the odors and provide additional resources.

• Conducted plume modeling using wind speed and direction information combined with complaint information during odor events to determine the potential location of the source.

• Collected and analyzed air samples to determine the types and levels of pollutants that are potentially present during the odor events.

Air Sampling Summary

The South Coast AQMD  may collect samples as a result of an odor investigation or during routine surveillance activities.   In addition, South Coast AQMD is working in collaboration with the Long Beach, Huntington Beach, and Seal Beach Fire Departments to collect air samples during their response to 911 calls for natural gas odors. Instantaneous samples (also known as grab samples) are collected when odors are present, and take less than a minute to collect. 

Once a sample is collected, it is delivered to the South Coast AQMD laboratory for analysis. Instantaneous (grab) air samples were collected on the dates indicated below.  Samples collected in SUMMA canisters were analyzed for the presence of volatile organic compounds. Samples collected in Tedlar bags were analyzed for TRS (total reduced sulfur).  For lab analysis results, click on the link for the type of analysis performed.

All reports below are in PDF format.

As part of the South Coast AQMD’s ongoing investigation into the source(s), staff are now focusing on the following:

• Continuing to respond to, and investigate, odor complaints and perform odor surveillance.

• Requesting further assistance from city, state, and federal agencies to aid in the investigation of the odors and provide additional resources.

• Continuing to perform surveillance along the shoreline between Huntington Beach, Seal Beach, and Long Beach with a FLIR camera to potentially identify sources venting to the atmosphere.

• Working with community members for the collection of samples during odor events. 

More Information:

• For more information, please contact the South Coast AQMD Public Advisor at publicadvisor@aqmd.gov.