Testing soil safety after wildfires
Protecting Angelenos from dangerous contamination with free rapid-response soil testing. Our Contaminant Level Evaluation and Analysis for Neighborhoods (CLEAN) project is a USC program separate from L.A. Dept. of Public Health soil testing.
USC Launched 2025
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Participating in CLEAN is easy and free of charge
CLEAN is designed to quickly provide Los Angeles residents with general updates on safety and the potential for exposure. This testing is rigorous and reliable, but it is not a substitute for in-depth environmental testing or remediation that may be needed in affected areas.
CLEAN is a project from USC, and is separate from L.A. County Department of Public Health soil testing. If you are looking for L.A. County’s Eaton soil testing program, please visit their website.
Impact
Angelenos are getting urgent information about the soil around their homes, parks, schools, and more—so they know whether it’s safe to garden or let kids and pets play outside. And they’re learning how to keep wildfire toxins from being tracked through their front doors.
3000+ properties tested to help people stay safe
Challenge
After the 2025 wildfires blanketed thousands of square miles in toxic debris, people countywide had the same urgent question: was it safe to stay home, or return to the ones they’d fled? With no government testing available, we stepped in to give Angelenos answers.
Our Plan
We were the first to launch a soil testing program after the wildfires—and CLEAN is still the only program collecting countywide samples. With earth scientists and health experts from USC, we’ve collected 3000 soil samples (and counting)—and have kept response times under three weeks. By setting up local drop spots and accepting samples from every district, we made this urgent service easier and more accessible for the people who need it most.
Project Goals
Give people answers about health risks
Our countywide soil testing program offers a full look at the scale of the wildfire contamination.
Help people stay safe
Our health and safety guides will help people protect themselves and their loved ones from dangerous toxins.
Investigate how contamination spreads
Our new water testing program tracks the sources of post-fire contamination in the watershed and its impacts on our beaches, rivers, and streams.
Approach
We combined clear collection instructions, local drop-off sites, and lab analysis to make soil testing simple—and we return results in plain language to help communities recover after the fires.
Lab-based analysis
Community engagement
Public communication
Here’s what our partners say
“CLEAN is helping to fill a critical need for widespread soil testing and rigorous environmental monitoring across the Los Angeles region period. An expanded project would produce tremendous benefit for our community.”
Church Leader for the Fifth Episcopal District of the African Methodist Episcopal Church
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