Ascon Final Remedy Work

Near real-time telemetry air monitoring results will be posted here when final remedy excavation begins. View the latest air monitoring results in advance of final cleanup work here.

A telemetry-based air monitoring network collects near real-time data during work hours. Work hours are from 7 a.m. to 6 p.m., Monday through Friday.

In addition to 24/7 air monitoring conducted at the perimeter of the Site and at neighborhood stations, a telemetry-based air monitoring network is collecting additional air quality data during work hours.

Telemetry-based air monitors around the active work area capture air monitoring data in near real-time. The telemetry network records total volatile organic compounds (VOCs) and dust data upwind and downwind of the work area. The Site contribution (concentrations detected downwind of the work area excluding upwind or background) 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 a harmful exposure or that the community’s health is at risk. Air monitoring 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. For the purposes 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 SCAQMD, and shared on our Actively Monitoring Air Quality webpage.

Scroll down to learn more on how to read the telemetry results.

To view data from the last week, last month, or all data, click on the   icon and select the timeframe you would like to view for both dust and VOCs.

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 25 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 the South Coast Air Quality Management District (SCAQMD) for total dust.

The results during work hours show Site contribution 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 the SCAQMD for total VOCs.

Additional offsite air monitoring is occurring with onsite telemetry monitoring. In the map to the right, you can see the locations of telemetry stations and ongoing onsite and offsite air monitors at upwind and downwind locations.

To learn more about Ascon’s onsite and offsite air quality monitoring data and approach, visit asconhb.com/air-monitoring.

Map is for illustrative purposes, locations are approximate.