Cleanup Activities

As we engage with our neighbors to complete the remediation work, the health and safety of the Huntington Beach community remains our highest priority.

What’s Been Done

Over the past 20 years, the Ascon team has made significant progress on cleanup efforts. Multiple cleanup actions were completed at the Ascon Landfill Site from 2005 to 2023. Together, the following actions included the removal of approximately 128,000 cubic yards of waste materials.

2005 – 2006

Emergency work was conducted to remove materials that were pressing against a decades-old earthen berm, the area was reinforced and extensive stormwater management actions were conducted after a 200-year rain event.

2007 – 2017

Extensive field investigations and analysis led to the development of various environmental documents that will determine the cleanup path moving forward. These received significant public review and input, including through community meetings.

2017 – 2019

Fieldwork was conducted to solidify much of the Lagoon 5 area, enabling closure of long-inactive, buried oil wells dating from the 1920s, as preparation for the final cleanup.

2019 – 2022

The final cleanup field work was initiated, but work was paused in June 2019 at DTSC’s direction to address community concerns. In 2020, an emergency repair of the northwest berm occurred, and borings and sampling for a technical sitewide odor analysis were taken. Pit F material was excavated and the tent was removed.

2023 – 2024

In coordination with DTSC, Ascon developed a pilot testing workplan to test Engineered Misting Containment (EMC) and Soil Vapor Extraction (SVE) pre-treatment onsite. Pilot work began in June 2023 and was completed in October 2023. Ascon will submit pilot test findings to DTSC and work to develop a restart plan and schedule. A public meeting will be held in advance of restart. Learn more about completed pilot work here.

Current Cleanup Plan

In 2015, the California Department of Toxic Substances Control (DTSC) approved a Final Remedial Action Plan (RAP) outlining cleanup activities for the Ascon Site. The cleanup plan was approved following a rigorous, multi-year public review and a formal Environmental Impact Report (EIR) process per the California Environmental Quality Act (CEQA).

Since work began in January 2019 on the activities outlined in the RAP, approximately a third of the excavation work has been completed.

The cleanup plan includes the removal and offsite disposal of impacted soils from the former Pit F, which was completed in 2021. Learn more about the Pit F work and telemetry air monitoring here. The remaining waste and soils will be excavated, graded, and covered in an engineered containment area that will be underneath a multi-layered environmental cap. After the final excavation and grading is complete, the environmental cap is constructed with geomembrane barriers, clean soils, and planted with native, drought-tolerant plants. The property will continue to be inspected and maintained long-term as secured open space with residential-style perimeter fencing. See what Ascon will look like at Future of the Site.

Ascon team hosting a safety tailgate meeting.

Ascon team member using a handheld device to sample air quality.

Current Cleanup Status

Since work was paused in June 2019 at DTSC’s direction to address community concerns about dust and odor, the Ascon team has introduced additional health and safety enhancements to protect the community. Under direction and oversight from DTSC, Ascon conducted emergency northern berm repair work in 2020, Pit F excavation and tent removal in 2021 and pilot work onsite testing in 2023. Ascon is currently working with DTSC to develop a restart plan based on pilot test findings.

Learn more about Engineered Misting Containment and Soil Vapor Extraction pre-treatment pilot work. Learn more about the Pit F excavation work here.

Check out Site Updates to find out what our team is doing this week on Site and in the community.

Investigations Guide Cleanup Actions

Numerous Site investigations have taken place over more than 30 years, including soil sampling, groundwater monitoring and air monitoring. We are using what we learned from the 2023 pilot work and the following investigations to guide our cleanup approach:

View the Revised Feasibility Study approved by DTSC in September 2007 to learn more.
Sampling and investigations conducted since 2002 found the impacts to shallow groundwater are contained within the Site boundaries.
Air monitoring is used to ensure air quality meets health-protective screening levels. Click here to learn more about air monitoring at the Site.

Frequently Asked Question

If work is paused, why are there still workers and materials onsite?

Our team is maintaining the Site, conducting air and groundwater monitoring, performing health and safety enhancements to control dust and odors, and providing Site security. These actions do not involve any remediation work.