Ascon Landfill Information

ascon aerial photo

The Site and the Clean-Up Effort. According to the clean-up Environmental Impact Report, the Ascon Landfill was an active landfill operated between 1938 and 1984. Industrial and oil field wastes were disposed at the landfill from 1938 to 1971. After 1971, construction debris (asphalt and concrete) were disposed at the Site until it was closed in 1984. The Site contains various types of liquid and solid waste in buried pits, surface piles of concrete, rebar and other construction debris, and fenced, open lagoons (ponds).

The Site has undergone several changes of ownership and environmental investigations since 1984. In 2003, DTSC and some of the Ascon Landfill Site Responsible Parties (RPs) entered into a Consent Order with the State of California for the Site’s cleanup. Preliminary remediation work began in July 2017 and has continued with full-scale remediation starting in 2019.

Currently, the clean-up effort is stopped, as DTSC works with the Responsible Parties (RP) on a checklist of items that DTSC believes need to occur before clean-up can start again. A June 12, 2019 letter that DTSC sent to the RP is here. Please take a look at it, including the last page. As you can see from the letter, DTSC is recommending looking at a tenting system, increasing the height of the fencing, coverage of soil, additional air quality monitoring, and more. The remediation is not to start up again until DTSC has signed off on these “health and safety enhancements."

The Agency Overseeing the Clean-Up. Site cleanup is directed by the State of California’s Department of Toxic Substances Control (DTSC), which is a department within the California Environmental Protection Agency or Cal-EPA. DTSC has oversight over the final cleanup, including monitoring the work and mitigation measures, and providing community information. The City of Huntington Beach is not overseeing the clean-up, nor are we issuing permits for it.

Our Concerns, Community Concerns. The City has been concerned about the full-scale remediation, especially after hearing from area residents about dust and odors from the activities. As those concerns started coming to us, we have been working with DTSC, the South Coast Air Quality Management District (AQMD), and others on this important issue. Our concerns include:

•    Clean-up should not result in dust or other materials leaving the site.
•    Air quality should be regularly monitored and reported to the public. In “real time”, if at all possible.
•    Clean-up areas should be tented or otherwise confined, if at all possible.
•    There should be a third-party technical advisor, not associated with Ascon or any of the other consultants working on the project, that provides all of us with good analyses and easy-to-understand information about data.
•    Area residents, the City, HBUSD officials, teachers, parents, and students should all be made aware of any air quality or other information at the same time that DTSC or others receive it.
•    We all must be kept apprised of site activities and progress towards remediation.
•    Acknowledging all of the above, the clean-up needs to progress. This material needs to be appropriately remediated for the long-term safety of our community.


For a summary of the questions from the community, please click here.

UPDATE as of March 24, 2023

Over the past two years, some additional progress has been made toward planning for the restart of remediation activities at the site. All activities were conducted in close coordination with the DTSC.

1.    Pit F Removal – Perhaps the most noticeable change on the site is the removal of Pit F and the associated white enclosure structure. In the summer of 2021, Ascon’s remediation consultants excavated the sticky, tar-like material from the pit, replacing it with cement slurry. The waste was sealed in bins lined with plastic and trucked offsite for disposal at a hazardous waste facility. After the pit’s materials were removed and it was sealed beneath cement, the enclosure structure was removed. All the details on the Pit F Removal can be found in the associated report on Envirostor.

2.    Odor Assessment – Ascon’s remediation consultants collected soil and soil vapor samples from points all around the site that represent the material that is to be excavated and moved as part of the final remediation work. The samples were analyzed for their potential to emit the extremely unpleasant odors that the surrounding community experienced in May-June of 2019. A number of “reduced sulfur compounds” were identified as the primary odor-causing chemicals. The soil areas that contained higher concentrations of these compounds were then mapped to assist with planning the odor mitigation strategies that will be put into place during remediation. All the details on the Odor Assessment can be found in the associated report on Envirostor.

3.    DTSC Staff Changes – Because of some internal promotions and restaffing, Safouh Sayed is no longer the primary point of contact at the DTSC for the Ascon Project. Clayton Larkins, PG has been on the job for several months, conducting weekly visits to the site, and is available to address concerns or assist with public inquiries. Clayton’s contact information has been added to the General Information Section below.

4.    Work Planning – Ascon and the DTSC have been working on several technical documents that should be completed before the end of April 2023. These documents have been doing through several rounds of critical evaluation by the DTSC and revision by Ascon’s environmental engineers.
       a.    The Enclosure Feasibility Evaluation is a document that will examine the feasibility and practicality of fully enclosing future soil excavation work at the site, in much the same way that Pit F was fully enclosed. 
       b.    The Soil Vapor Extraction Pilot Test Work Plan will review the possibility of using vacuum extraction to remove and treat volatile soil vapors directly from the subsurface while excavating in order to minimize the amount of odorous vapor that escapes into the atmosphere. 
       c.    The Engineered Misting Control Pilot Test Work Plan will evaluate methods for doing a much better job of suppressing dust, vapors, odor, and mist overspray than the methods being used in 2019, which were demonstrably inadequate.

5.    Public Communication – Following the approval of the above documents, the DTSC will hold a public information session to go over the details of the plans and answer questions from the community. This session will be held before the start of any work on the site. We expect the details (date, time, location, and format) to be announced soon.

General Information

How can I find out more? General project information can be found at and at We encourage you to contact the following people directly with questions or concerns:

Clayton Larkins, PG, DTSC Site Mitigation and Restoration Program
[email protected]  

Jessica Anderson, DTSC Public Participation Specialist 
(714) 484-5354 
[email protected] 

Tamara Zeier, P.E., Project Navigator Ascon Landfill Project Coordinator
(310) 766-0116
[email protected]  

The City has also provided another avenue for residents to get their questions answered by hiring a Third-Party Technical Advisor. In an effort to help local residents understand the environmental cleanup process being conducted by Ascon at the landfill site, the City has hired Andrew Cherene, PG with HDR to act as an independent, third-party technical advisor to any resident who may have questions about the cleanup. Andrew has been an environmental consultant for 17 years, specializing in contaminated site assessments and clean-ups all around Southern California. As part of our continued effort in transparency and ongoing outreach effort in addition to assisting residents to better understand the complicated science with the clean-up work, residents may submit Ascon questions directly to Andrew. Ask Andrew a question at [email protected].   In addition to the above Andrew is compiling an ongoing list of answers to questions asked by the community and click here for a pdf of that file.

What if I have more immediate concerns? A 24-hour NON-EMERGENCY public hotline has been established by the Ascon Landfill Site project team to ensure questions or concerns can be answered promptly. DTSC receives documentation of the calls made to the project hotline. The Ascon Landfill Site hotline number is 714-388-1825. As always, in the event of an emergency, please call 9-1-1.

For more information about the Ascon Landfill visit:

Did you know?

The Huntington Beach Fire Department charges for emergency medical services and ambulance transportation.  However, residents can join the FireMed Program and protect their out-of-pocket costs!  Read more about the FireMed Program.

Contact Information

[email protected]

A 24-hour NON-EMERGENCY public hotline has been established by the Ascon Landfill Site project team to ensure questions or concerns can be answered promptly. DTSC receives documentation of the calls made to the project hotline. The Ascon Landfill Site hotline number is 714-388-1825.

Contact Information

City of Huntington Beach
Public Works Department
2000 Main Street
Huntington Beach, CA
Phone: (714) 536-5431
Fax: (714) 374-1573

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