At a glance, the community garden plot appears bountiful. Its beds, flanked by lavender plants, are lush with parsley, lettuces and kale that are weeks overgrown.

But a sign on the gate forbids entry, describing the site as “DANGEROUS TO YOUR HEALTH.”

In the foothills of the San Gabriel Mountains, the Altadena Community Garden is adjacent to the more than 14,000 acres that were scorched by the Eaton fire in January. Across the road are burned-out homes, crumpled roofs and the husks of cars.

State and federal leaders have touted the speed with which cleanup efforts have occurred here and in Pacific Palisades, where a separate fire burned more than 23,000 acres. President Trump made clear in January that he felt residents should be able to rebuild immediately, and Gov. Gavin Newsom of California said last month that hazardous waste had been removed at “a record pace never seen before at this scale.”

Still, fears abound that pollutants could linger on the land long after federal authorities clear about 4.25 million tons of waste from the two fires, including ash, debris and topsoil. What if, after the cleanup, toxic pollutants remain behind?

“We want to be able to plant fruit trees that we can use,” said Laura Siahaan, an Altadena mother of two children who lost her home in the fires. “We want our kids to be able to play outside.”

Rebuilding, in her mind, means “not having any toxic remnants from this fire that follow us for years.”