Chiquita Canyon Landfill Pollution Lawsuit and Health Impacts

The Chiquita Canyon Landfill lawsuit is actually two parallel actions in federal court in the Central District of California: a consolidated mass tort brought by roughly 11,700 residents of Val Verde, Castaic, Hasley Canyon, and Santa Clarita, and a separate suit filed by Los Angeles County in December 2024. Both target the landfill’s operator, Chiquita Canyon LLC, along with Chiquita Canyon, Inc. and their parent company, Waste Connections US, Inc. The claims center on toxic emissions and hazardous leachate produced by a smoldering underground reaction that began around May 2022 and continues today.¹²

What the Lawsuit Is About

Regulators call the event a Subsurface Elevated Temperature reaction. Deep in an inactive section of the 639-acre landfill in Castaic, ordinary decomposing garbage reached a tipping point where biological breakdown gave way to self-sustaining chemical reactions. State agencies say the affected area now covers roughly 90 acres, more than three times the 28-acre figure the operator has used.³

The reaction generates two things that drive the litigation. First, a foul gas rich in carbon dioxide, hydrogen, and dimethyl sulfide, the compound responsible for much of the stench that has drawn more than 29,000 odor complaints. Second, huge volumes of leachate, a toxic liquid byproduct that surged from about 150,000 gallons per week in early 2022 to more than a million gallons per week by December 2023. Testing has shown elevated benzene, a known carcinogen, which led regulators to classify the leachate as hazardous waste under federal rules.⁴³

Health Harms Alleged by Residents

Residents in the communities closest to the site report chronic headaches, nausea, nosebleeds, respiratory distress, fatigue, dizziness, tremors, and skin irritations. Some have reported cancer diagnoses, including cases of acute myeloid leukemia, which medical literature links to benzene exposure.⁵

Air monitors near the landfill have picked up benzene readings above one-hour and eight-hour safety standards, and more than a third of hydrogen sulfide readings have exceeded state standards. Residents have also reported that pets and livestock suffered sudden deaths, tremors, and respiratory problems.⁵⁶

No government-led epidemiological study has been conducted. The Los Angeles County Department of Public Health ran a voluntary online health survey from October 2024 through February 2026; participants reported headaches, eye and throat irritation, and major disruptions to daily life.⁷ The landfill operator has pointed to reports from an independent toxicologist concluding there are “no expected short- or long-term health impacts,” a claim community advocates and some outside researchers dispute.⁵

The Resident Mass Tort: Who Can Join

Individual claims by residents have been consolidated into In re Chiquita Landfill Litigation, Master File No. 2:23-CV-08380-MEMF-MAR, in the U.S. District Court for the Central District of California. As of February 2026, roughly 11,700 plaintiffs are part of the consolidated case, and new filings continued as recently as that month.¹

This is a mass tort, not a class action. Each plaintiff’s case is treated individually rather than resolved as one group claim, and multiple law firms represent different groups of plaintiffs. The Kruger Law Firm, for example, initially filed on behalf of more than 800 residents, schoolchildren, and employees in Val Verde, Castaic, and Valencia. Eligible claimants generally include anyone who lived, worked, or attended school near the landfill and experienced health symptoms, property damage, or financial losses tied to the toxic emissions.⁸

No trial date or settlement has been reported in the consolidated resident litigation as of early 2026.

The Los Angeles County Lawsuit

On December 16, 2024, Los Angeles County sued Chiquita Canyon LLC, Chiquita Canyon, Inc., and Waste Connections US, Inc. in federal court, alleging public nuisance, violations of the California Unfair Competition Law, and violations of the Los Angeles County Code. The County asked for an injunction halting noxious emissions, orders requiring temporary relocation of nearby residents until the underground reaction is contained, and civil penalties.²⁹

Chiquita Canyon called the lawsuit “misguided and counterproductive” and said it would “vigorously contest” the claims.¹⁰

On August 29, 2025, a federal judge granted the County a preliminary injunction ordering the landfill operators to work with the County on a plan for temporary relocation and home-hardening assistance for affected residents in Val Verde, Castaic, and Santa Clarita. The plan was due within 30 days.¹¹ Waste Connections appealed to the Ninth Circuit on September 10, 2025. As of early 2026, the appeal is fully briefed but no oral argument date has been set, and the district court has not ruled on the company’s request to stay the injunction during the appeal.¹

The County’s case has been consolidated with the resident litigation for discovery purposes, though it keeps a separate case number, 2:24-cv-10819-RGK-PD.¹

Who Is Being Sued

Three corporate entities are named across the litigation:

Waste Connections US, Inc., a Delaware corporation headquartered in The Woodlands, Texas. It bought the landfill in 2009 through a subsidiary and is the parent of the operating entities.¹²
Chiquita Canyon, Inc., a Delaware corporation that operated the landfill until 2017 and remains a Waste Connections subsidiary.¹²
Chiquita Canyon LLC, a Delaware limited liability company that has been the primary operator since 2017.¹²

Outside of court, Waste Connections reported $75 million in closure-related spending for the site during 2024 and has paid roughly $23.5 million to $25 million in community relief payments to nearly 1,830 households, along with distributing thousands of air purifiers and carbon filtration systems for local schools. Those payments are not a settlement of the litigation.¹³⁶

Regulatory Actions Running Alongside the Litigation

The lawsuits sit on top of a stack of federal, state, and local enforcement actions that have produced findings the plaintiffs are likely to lean on.

On February 21, 2024, the U.S. EPA issued a Unilateral Administrative Order under RCRA Section 7003 and CERCLA Section 106, finding the landfill presents an “imminent and substantial endangerment to the public health or the environment.” The EPA followed with a Clean Air Act Finding of Violation in June 2024, and has continued to add requirements, including a mandate for 100 more acres of geomembrane cover in July 2025 and orders for leachate aeration treatment and a west-slope buttress in March 2026.¹⁴⁴

California’s Department of Toxic Substances Control has cited the landfill for 81 violations of the state Hazardous Waste Control Law. Its April 2025 Imminent and Substantial Endangerment Order required the operator to relocate the leachate storage tank farm, expand the geosynthetic cover over the entire reaction area, and address slope stability. In January 2026, DTSC issued a Determination of Non-Compliance for failure to submit adequate workplans, exposing the companies to daily fines of up to $25,000 until an acceptable plan is produced.¹⁵¹⁶

The South Coast Air Quality Management District has issued about 340 Notices of Violation since January 2023 for public nuisance under its Rule 402 and the California Health and Safety Code, based on the more than 29,000 odor complaints. Its Hearing Board’s September 2023 Order for Abatement has been amended repeatedly to tighten monitoring and inspection requirements, with a further status hearing scheduled for late May 2026.¹⁷¹

Where the Case Stands in 2026

Waste Connections permanently stopped accepting waste at the site on January 1, 2025, citing the “current regulatory environment” and the inability to run economically under tonnage restrictions.¹³ Closing the gates has not ended the underlying problem. A March 2025 CalRecycle analysis found the operator’s containment strategy “has failed” and that no barrier is currently in place to stop the reaction from spreading into the entire 160-acre canyon of buried waste. State regulators say the reaction could persist for decades. Waste Connections disputes that assessment, saying its mitigation efforts have produced “positive results.”³

Groundwater monitoring has picked up 1,4-dioxane at a well installed in April 2025 on an adjacent landowner’s property (detected in June 2025), and trace benzene has appeared consistently in at least one evaluation monitoring well near the reaction area.¹⁸

The consolidated mass tort case involving roughly 11,700 plaintiffs remains in active litigation, with no reported settlement or trial date. The County’s preliminary injunction ordering relocation assistance stands while Waste Connections’ Ninth Circuit appeal awaits oral argument. On the regulatory side, DTSC’s daily fines are accruing, the EPA continues to add mitigation deadlines, and the underground reaction continues to burn.¹

1
U.S. SEC. Waste Connections SEC Filing
2
Kathryn Barger, LA County Supervisor. Los Angeles County Files Lawsuit Against Chiquita Canyon Landfill Owners
3
Los Angeles Times. State Orders Chiquita Canyon Landfill to Take Corrective Measures or Face Fines
4
U.S. EPA. Chiquita Canyon Landfill
5
Inside Climate News. LA County Chiquita Canyon Landfill Toxic Waste Pollution
6
CalMatters. Chiquita Canyon Landfill California
7
LA County Department of Public Health. Chiquita Canyon Landfill Community Health Survey
8
PR Newswire. Kruger Law Firm Files Mass Tort Lawsuit Against Chiquita Canyon Landfill
9
ABC7. LA County Sues Chiquita Canyon Landfill
10
Chiquita Canyon. Statement Regarding LA County Lawsuit
11
Assemblywoman Pilar Schiavo. New Court Order Moves Relief Forward for Residents Impacted by Chiquita Canyon
12
CaseMine. Howse v. Chiquita Canyon, LLC
13
Waste Dive. Waste Connections Chiquita Canyon Landfill Close
14
U.S. EPA. EPA Finds Chiquita Canyon Landfill Presents Imminent and Substantial Endangerment
15
DTSC. State Officials Find Chiquita Canyon LLC Out of Compliance
16
DTSC. Chiquita Landfill
17
South Coast AQMD. South Coast AQMD Issues Multiple Violations to Chiquita Canyon Landfill
18
Chiquita Canyon. Semiannual Groundwater Monitoring Report