A massive federal cleanup operation launched after the deadly Eaton Fire appears to have worked, according to new soil testing results released by the US Environmental Protection Agency.

The EPA said 98% of tested properties in the Eaton Fire burn zone met federal safety standards for lead levels found below the surface.

Another 95% met federal standards for lead levels in surface soil after cleanup crews completed their work.

The findings follow the January 2025 wildfires that tore through Altadena neighborhoods, destroying homes and raising serious concerns about toxic contamination left behind in ash and soil.

Federal crews led by the US Army Corps of Engineers removed burned debris and scraped away the top six inches of soil beneath destroyed homes as part of the cleanup effort ordered after the fires.

The new testing suggests those efforts were largely successful.

More than 4,200 soil samples were collected from 100 randomly selected destroyed properties where federal cleanup crews had already finished debris removal work.

According to the EPA, 95 out of 100 surface soil samples collected near the homes’ building footprints tested below the federal lead screening level.

Officials said the results confirmed that federal cleanup methods significantly reduced lead contamination across the burn zone.

“Protecting human health and the environment is our top priority, especially in the aftermath of terrible tragedies,” Acting EPA Pacific Southwest Regional Administrator Mike Martucci said. “The Trump EPA engaged in this proactive exercise to ensure our partners have verified, science-backed EPA cleanup protocols that will inform responses to future wildfire disasters and continue to protect American communities.”

The EPA has not publicly released the full report, but officials said lead levels found in the tested soil came in well below the agency’s residential safety threshold of 200 milligrams per kilogram.

That federal standard is designed to protect residents, especially children, from dangerous exposure.

Lead is a powerful neurotoxin that can harm brain development and cause behavioral problems in children who inhale or ingest it.

When the Eaton Fire ripped through Altadena’s historic neighborhoods, many older homes coated with lead-based paint burned to the ground. 

Smoke and ash from the fire then spread lead particles throughout the surrounding area, creating fears about long-term contamination in residential soil.

The cleanup and testing operation was funded by the Federal Emergency Management Agency and carried out by EPA scientists.

The EPA focused its testing specifically on the Eaton Fire zone after a 2025 study by the Los Angeles County Department of Public Health found lead was the only wildfire-related contaminant considered a major concern in local soil.

Officials said elevated lead levels were detected in the Eaton burn area but not in the Palisades fire zone.

To complete the study, crews collected soil from 30 different locations on each destroyed property.

Samples were taken from the surface and from six to seven inches underground before being analyzed at an EPA laboratory.

Officials noted that some properties may still show higher lead levels because contamination can also come from older pollution sources unrelated to the wildfire, including industrial emissions, traffic pollution, and household activities over many years.

The EPA said homeowners whose properties exceeded federal screening levels have already been contacted directly and provided guidance from the Los Angeles County Department of Public Health.

The EPA and LA County health officials are expected to discuss the soil testing findings during the Altadena Town Council meeting on June 16.