Actively Monitoring Air Quality
Nothing is more important than the health and safety of the Huntington Beach community and our workers as we work together to finish the cleanup of the Ascon Landfill Site. This includes working to protect the health and safety of the community by monitoring air quality at the Site.
Ascon’s air quality monitoring data since 2019 have shown that air quality has consistently met health-protective screening levels and has been safe, including during active work. All air monitoring data are reviewed by the Department of Toxic Substances Control (DTSC) and posted to this webpage.
Air Monitoring Approach
Current Onsite Monitoring: Six onsite near real-time telemetry air monitoring stations monitoring for dust and total Volatile Organic Compounds (VOCs) are located around the Site perimeter.
Learn more about how Ascon conducted air monitoring during previous remedial fieldwork here and learn more about air monitoring practices during 2019-2023 onsite activities here.
A system of remote sensors around the perimeter of the Site that captures air quality data, such as total VOCs and dust, upwind and downwind of the work in near real-time.
An “action level” is an amount of a substance established by regulatory agencies that is protective of public health. Action levels help determine if work on-site is creating an issue, usually focusing on the “site contribution” (downwind minus upwind levels).
Site contributions are displayed and compared to the Site action levels, confirming air concentrations are below action levels. If a brief telemetry reading is above an action level, it does not mean that there was harmful exposure or that the community’s health is at risk. It means controls must be reviewed.
Air monitoring action levels are used during the work at Ascon to guide mitigation actions, to stop work actions and to prompt increased actions to control potential odor, emissions or dust. For the purpose of evaluating potential community exposures, air data are evaluated over 24-hour periods and longer. The air data are submitted to DTSC, available for review by South Coast Air Quality Management District (SCAQMD) and shared on our Actively Monitoring Air Quality webpage.
Air monitoring screening levels were approved by DTSC and reviewed by SCAQMD. They take several factors into account, including the type of substances that may be present, the detections in the air and how long the potential exposure lasts. The levels are set to be protective of potentially sensitive members of the community (e.g., children, pregnant women, those with health concerns) and are for both short-term and long-term exposures, such as daily exposure over a lifetime.
If a dust or total VOC reading is above their action level, it does not mean that the community’s health is at risk, but allows onsite teams to adjust mitigation efforts.
Dust
The results during work hours show Site contribution dust levels in two-hour intervals. Telemetry is a tool that can guide and inform active work. If a dust reading is above 50 ug/m3, it does not mean that the community’s health is at risk but allows onsite teams to adjust dust mitigation efforts.
Air monitoring action levels were approved by DTSC and SCAQMD for total dust.
VOC
The results during work hours show Site contribution total VOC levels in two-hour intervals. Telemetry is a tool that can guide and inform active work. If a reading is above an action level, it does not mean that the community’s health is at risk but allows onsite teams to adjust work and mitigation efforts.
Air monitoring action levels were approved by DTSC and SCAQMD for total VOCs.
Air monitoring is currently occurring at the following onsite perimeter locations:
Onsite Total VOC Concentrations and Dust Monitoring Results
Onsite and Offsite Dust Monitoring Results
To view archived air monitoring results posted by DTSC on Envirostor, click on Community Involvement Documents, and scroll to Updates and Information.
Air Monitoring Glossary
An amount of a substance established by regulatory agencies that is protective of public health. Action levels are used during the work at Ascon to guide mitigation actions, stop work actions, and prompt increased actions to control potential odor, emissions or dust.
The air occurring at a particular time and place outside of structures. Often used interchangeably with “outdoor air”.
The periodic or continuous sampling and analysis of air pollutants in ambient air or from individual pollution sources.
Have a Question or Concern?
Please contact the Ascon community information line at 714-388-1825 or email info@asconhb.com. If there is a potential emergency, please call 911. Sign up for AsconAlert, an opt-in community alert system for the Ascon project here.
Stay Informed
Please subscribe for email updates.
Information provided through this website may be shared with the Ascon team, Ascon consultants, Ascon responsible parties and government agencies. Read our Privacy Policy.