The South Coast Air Quality Management District Hearing Board approved modifications Wednesday to an Order for Abatement requiring Chiquita Canyon Landfill to address ongoing concerns at its facility. Foul odors from Chiquita Canyon have continued to significantly impact the public since early 2023, and South Coast AQMD sought to modify the Order to address issues relating to the facility’s liquid leachate collection system, as well as other conditions resulting in increased emissions. Additionally, expanded air monitoring and sampling in the nearby community was requested, with all data to be made publicly available.

The Chiquita Canyon Landfill is a landfill/solid waste disposal facility located at 29201 Henry Mayo Drive in Castaic. In 2023, South Coast AQMD received more than 7,000 odor complaints that were traced back to the facility and, to date, has issued approximately 110 Notices of Violation (NOVs) against Chiquita Canyon for public nuisance in violation of the agency’s Rule 402 and California Health & Safety Code Section 41700. In November 2023, South Coast AQMD also cited the facility for failure to maintain the leachate collection and storage system in good operating condition, failure to report the breakdown of equipment, failure to submit a landfill excavation plan, and violations of other permit conditions. Leachate was observed on numerous occasions bubbling, boiling, or shooting out like a geyser. The pooled and flowing liquid is seeping out of the soil and causing additional foul-smelling odors.

A review of Chiquita Canyon’s air monitoring data showed approximately 35% of all hydrogen sulfide (H2S) readings over the past year exceeded the California state standard of 30 parts per billion (ppb), averaged over one hour. Chiquita Canyon Landfill is currently experiencing a subsurface reaction over an inactive portion of the landfill that is causing increased temperatures, increased production of landfill gas, and increased production of leachate, as well as fugitive emissions of landfill gas from the surface of the landfill. The area affected by this reaction is located approximately 1,000 feet from the nearest resident.

Wednesday’s modified Order requires Chiquita Canyon to take significant actions, such as:

– Immediate Leachate Collection: Twice daily inspections for leachate and the immediate removal of any pooling or ponding liquid in a sealed tank/truck.

– Excavation Plan and Interim Mitigation: Submit a complete excavation plan that includes proper management of soil, methane monitoring, dust suppression, and the immediate relocation of any excavated soil from the property. Until the plan is approved, the landfill must undertake interim mitigation measures to limit odor and fugitive dust during excavating activities.

– Expand Collection and Extraction Wells: To collect gas and leachate as needed and properly cover wells to prevent leaks, as well as take precautions to avoid or limit escape of any liquids during well building or maintenance.

– Expanded Monitoring: Install continuous air monitors in the community where odors have been reported for gases associated with landfills. Monitor for benzene and other volatile organic compounds (VOCs). Increase laboratory sampling in the community to 3 times per week until the monitors are in place. Take monthly samples of leachate at the reaction area, the areas with the highest temperature, and the bottom of the tanks where leachate is stored. Conduct an additional study of surface air emissions from the landfill.

– Increased Transparency: Provide all past and current air monitoring data to South Coast AQMD immediately for review. Develop a webpage to display real-time monitoring information within 30 days.

South Coast AQMD’s Modified Order for Abatement was granted by the South Coast AQMD Hearing Board. The Hearing Board is an independent panel that hears all sides of a case, weighs the evidence, and reaches a decision. A status hearing will be held on April 24 and 25, 2024, or as soon thereafter as it can be scheduled with the Hearing Board. South Coast AQMD is the regulatory agency responsible for improving air quality for large areas of Los Angeles, Orange, Riverside and San Bernardino counties, including the Coachella Valley.