Shortly after buying her house in 2022, Mary Royers learned from a man across the street that her Omaha, Nebraska, neighborhood was contaminated with lead. But her yard, like thousands of others, had been cleaned up, the neighbor said.

Royers wanted to be sure. So the 36-year-old educator checked a website where the city tracks the soil test results of every home in a 27-square-mile area surrounding the site of an old lead smelter. She saw “remediated” written in bright green letters. The federal government had completed the work two decades ago. An expert must have tested the dirt and determined the problem was solved, she thought.

Relieved, Royers set about sowing the garden of her dreams. Hours disappeared as she thrust her hands into the soil, tearing up the grass and planting purple coneflower for bees to harvest and prairie grass to sway in the breeze.

“You have the green light from the city. That means everything’s safe,” she said. “I remember thinking, ‘Thank God I don’t have to worry about that.’”

But a soil test conducted last fall by the Flatwater Free Press and ProPublica found otherwise: Royers’ yard still has more than 1.5 times the level of lead that the Environmental Protection Agency’s cleanup was supposed to have eliminated.

Reading the emailed results, she felt “gut-wrenching disbelief,” she said.

“All I could think about was the dirt under my nails and all over my face,” said Royers, who has largely given up gardening for now. She explained later, “It felt like a betrayal of that trust.”

Since 1999, the EPA has spent $273 million digging up and backfilling nearly 14,000 yards across east Omaha to address contamination left from the smelter and other factories downtown. It’s the largest residential lead cleanup in the country. And the agency’s Superfund program has repeatedly heralded it as a success.

But, it turns out, Omaha’s soil might not be as safe as officials have advertised. The news organizations tested soil from more than 600 properties, including 150 that the EPA said had been cleaned up. In those tests, 1 in 10 yards marked as remediated still had enough lead to qualify for cleanup under the original guidelines. And nearly a quarter of the properties we tested in east Omaha could qualify for further study under new guidance released by the Trump administration last fall.

How We Tested Omaha’s Soil

The Flatwater Free Press and ProPublica used the EPA’s protocol as guidance for taking samples and used an EPA-accredited lab. But our testing method differed from the EPA’s approach in that we typically took one sample per yard, while the EPA collected multiple samples and averaged them. The EPA said our approach may underestimate or overestimate the average contamination. Experts said it is likely to underestimate contamination. Learn more.

The results suggest the EPA has more work to do, said Howard Mielke, a longtime researcher of lead-contaminated soil who’s considered one of the field’s foremost experts. Not only should the agency clean up the areas that tested above the remediation level, he said, but it also should test other homes.

“If you find a couple of high results, chances are many high results will be nearby,” said Mielke, an adjunct professor at the Tulane University School of Medicine.

Some experts and environmental advocates said our findings reflect weaknesses in the EPA’s approach to cleaning up residential lead sites, which can leave a lot of lead behind.

Jeff Tittel, former director of the Sierra Club in New Jersey, the state with the most Superfund sites, said he repeatedly watched the EPA declare its work done after wrongly assuming everything had been cleaned up.

“On paper, everything’s wonderful,” he said, “but at the sites, there’s still chaos.”

The EPA declined an interview request with senior officials overseeing the Omaha cleanup.

In an emailed response, spokesperson Kellen Ashford said the EPA is committed to cleaning up contaminated sites to protect residents and the environment. “The diligent cleanup efforts have led to a dramatic decrease in elevated blood lead levels” in Omaha, he said. (While the........

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