L.A. County Didn't Warn Castaic Landfill Neighbors of Chemical Spikes, Audit Finds

The 65-page state report says Public Health got air readings above state thresholds and never told residents, who report headaches and nausea.

L.A. County's health department didn't tell neighbors of the Chiquita Canyon landfill when air reports showed chemicals above state limits, a state audit found.

The 65-page review, first reported by LAist on Wednesday, looked at how the Los Angeles County Department of Public Health handled the landfill in Castaic. The site has been giving off fumes and a stench for years. People living near it have described headaches, nausea and trouble breathing.

That matters for a long time to come. The landfill closed in 2025, but officials expect the chemical reaction burning underneath it to keep going for years. The families in Castaic and Val Verde will be living next to it the whole way through.

What the auditors found

The landfill's operator sent the department air-quality reports, and some of them showed chemical levels over state thresholds. According to the audit, Public Health didn't share those readings with the public, and it couldn't show that it had reviewed the data consistently.

County officials told the auditors that crossing a threshold doesn't by itself decide how risky the air is, and that they weigh a range of factors. The auditors weren't persuaded that this excused the silence. The department could have commented on the quarterly reports or published its own health assessment, they wrote, even when it saw no danger. Without that, the audit said, residents went without "timely and important information" about what the exceedances meant for their health and safety.

The review turned up two more gaps. Most of what the department knew about residents' symptoms came from data nearly two years old. And it didn't offer mental health resources to the community, though it had done so after a different hazardous incident.

Assemblymember Pilar Schiavo asked the Legislature for the audit. She said it backed up what her constituents had been saying for years, that the county's response "has not matched the seriousness of what families are experiencing."

The county pushes back

A department spokesperson told LAist it was "disappointing" that the audit mostly judged Public Health on its own, rather than as one piece of a response that federal, state and local agencies built together. In the spokesperson's telling, Public Health got to work early on residents' health concerns, and its approach "was iterative and evidence-based."

The auditors want the department to post monthly health assessment updates whenever chemical levels run high, and to check in with residents about their symptoms on a regular schedule. The department didn't agree to many of the specific recommendations, LAist reported.

So Public Health disputed the grade and a good share of the homework.

Supervisor Kathryn Barger, whose district includes the neighborhoods around the landfill, said she favors "letting subject matter experts lead" and that Public Health is working with state and federal agencies. She said her focus is the county's lawsuit against the landfill's operators, filed in late 2024.

What comes next

Schiavo said she'll hold a hearing on the audit and look at how to put its recommendations into effect. "Every day we don't act, our community members suffer," she said.

Source: laist.com, retrieved September 30, 2026.