Legal and Regulatory Action
Local, State, and Federal Governments are taking actions to require Waste Connections to address the public health and environmental impacts of the reaction. Here we provide a summary of important and current actions from the different government agencies involved in the response, as well as the landfill’s response to these actions.
For more information - Chiquita Canyon Landfill, Castaic, CA | US EPA
US EPA has issued a Unilateral Abatement Order requiring the landfill perform response actions to address off-site impacts, such as noxious odors, and the ongoing subsurface reactions at the landfill that are causing the off-site impacts. This includes properly managing leachate, including storing, transporting and disposing of leachate characterized as hazardous waste. Most recently US EPA has issued three work orders:
US EPA has issued a Unilateral Abatement Order requiring the landfill perform response actions to address off-site impacts, such as noxious odors, and the ongoing subsurface reactions at the landfill that are causing the off-site impacts. This includes properly managing leachate, including storing, transporting and disposing of leachate characterized as hazardous waste. Most recently US EPA has issued three work orders:
- On July 25, 2025, US EPA issued a letter directing Chiquita Canyon LLC to expand existing geomembrane cover atop the landfill with at least an additional 100 acres of ethylene vinyl alcohol (EVOH) geomembrane cover on the landfill surface. The work is required to be completed by December 1, 2026.
- On March 17, 2026, US EPA issued a letter directing Chiquita Canyon LLC to construct a soil buttress to prevent slope failure. Construction of the buttress was completed Fall 2026.
- On March 17, 2026, US EPA issued a letter directing Chiquita Canyon LLC to implement additional treatment to leachate being removed from the landfill including the installation of an aeration system to remove volatile organic compounds from their waste stream. The additional treatment was completed in May 2026.
- On October 19, 2026, US EPA issued an additional work order to Chiquita Canyon, LLC to make improvements to its landfill gas collection and control system. The letter directs work from Fall 2026 through calendar year 2027.
For more information - Chiquita Canyon Landfill | Department of Toxic Substances Control
On April 2, 2025, DTSC issued an Imminent and Substantial Endangerment (ISE) in a Order to the landfill requiring several protective actions. The order requires the landfill to relocate a tank farm away from areas in which the SET event could expand to; to expand the geosynthetic cover to all areas of the Landfill to which the reaction has expanded or has the potential to expand; and to take actions to protect critical infrastructure and slope stability.
On January 26, 2026, DTSC issued a Final Determination of Noncompliance to the landfill regarding its failure to comply with the Imminent and Substantial Endangerment Order.
On October 27, 2026, DTSC filed a lawsuit against Chiquita Canyon, LLC, Chiquita Canyon, Inc., and Waste Connections US, Inc (Waste Connections). The lawsuit alleges that Waste Connections has failed to comply with the California Hazardous Waste Control Law, violated the state’s Unfair Competition Law and polluted, impaired or destructed California’s natural resources. The lawsuit brings a dozen causes of action, including failure to minimize the possibility of unplanned spills of hazardous waste, unlawful storage of hazardous waste, failure to provide accurate information about the transport of hazardous waste, and conspiring to engage in unfair competition.
On April 2, 2025, DTSC issued an Imminent and Substantial Endangerment (ISE) in a Order to the landfill requiring several protective actions. The order requires the landfill to relocate a tank farm away from areas in which the SET event could expand to; to expand the geosynthetic cover to all areas of the Landfill to which the reaction has expanded or has the potential to expand; and to take actions to protect critical infrastructure and slope stability.
On January 26, 2026, DTSC issued a Final Determination of Noncompliance to the landfill regarding its failure to comply with the Imminent and Substantial Endangerment Order.
On October 27, 2026, DTSC filed a lawsuit against Chiquita Canyon, LLC, Chiquita Canyon, Inc., and Waste Connections US, Inc (Waste Connections). The lawsuit alleges that Waste Connections has failed to comply with the California Hazardous Waste Control Law, violated the state’s Unfair Competition Law and polluted, impaired or destructed California’s natural resources. The lawsuit brings a dozen causes of action, including failure to minimize the possibility of unplanned spills of hazardous waste, unlawful storage of hazardous waste, failure to provide accurate information about the transport of hazardous waste, and conspiring to engage in unfair competition.
For more information - Odor Incident - LA County Planning
Los Angeles County contains many different departments engaged in the response. The County regulates land-use, serves as the Local Enforcement Agency (LEA) for CalRecycle landfill regulations, and works to safeguard public health.
In its public health role, on April 14, 2026, LA County Department of Public Health issued a directive requiring the landfill to develop a Community Exposure Mitigation Plan (Plan) to reduce potential community exposures in the event of a slope failure. On July 31, 2026, after reviewing revisions of their initial plan, LACDPH issued a formal determination of non-compliance with the directive to Waste Connections, who has submitted a subsequent revision of the plan currently under review.
Los Angeles County contains many different departments engaged in the response. The County regulates land-use, serves as the Local Enforcement Agency (LEA) for CalRecycle landfill regulations, and works to safeguard public health.
In its public health role, on April 14, 2026, LA County Department of Public Health issued a directive requiring the landfill to develop a Community Exposure Mitigation Plan (Plan) to reduce potential community exposures in the event of a slope failure. On July 31, 2026, after reviewing revisions of their initial plan, LACDPH issued a formal determination of non-compliance with the directive to Waste Connections, who has submitted a subsequent revision of the plan currently under review.
In its role as the LEA on May 1, 2025, the County issued an order mirroring the DTSC order requiring the landfill to install an approved geomembrane cover and move hazardous waste storage and treatment to an acceptable location. On November 20, 2025, the LEA clarified that the geomembrane must be installed across the entire facility where waste is disposed by August 31, 2026. Waste Connections has not fully complied with this order.
On December 16, 2024, Los Angeles County filed a lawsuit against Waste Connections seeking to address ongoing environmental and public health hazards caused by the landfill’s operations and seek relief for impacted communities. The lawsuit provides additional details regarding the County's ongoing enforcement measures against the landfill. This litigation is on-going.
On December 16, 2024, Los Angeles County filed a lawsuit against Waste Connections seeking to address ongoing environmental and public health hazards caused by the landfill’s operations and seek relief for impacted communities. The lawsuit provides additional details regarding the County's ongoing enforcement measures against the landfill. This litigation is on-going.
Waste Connections is creating a public nuisance through the reaction at the landfill, are operating without required air pollution permits, are emitting sulfur dioxide levels in excess of regulatory requirements, and are violating Title V permit requirements. As a result, the South Coast Air Quality Management District Hearing Board issued an abatement order on September 6, 2023. That abatement order has been updated nine times to address on-going non-compliance with regulatory requirements, and was most recently updated on June 6, 2026.
On May 13, 2026, South Coast AQMD filed a lawsuit against Waste Connections for civil penalties associated with non-compliance with air quality requirements. The lawsuit alleges willful and intentional release of air contaminants, and negligent violations of the abatement order.
