Plutonium alert came late

Radiation test at former Navy base exceeded limits. Residents weren't told for 11 months.

- BY TONY BRISCOE AND SUSANNE RUST

CARLOS AVILA GONZALEZ San Francisco Chronicle AT HUNTERS POINT Naval Shipyard in San Francisco, shown in 2018, plutonium-239 was found to exceed the Navy's "action level."

More than a half century after the U.S. ignited 67 atomic weapons in the central Pacific Ocean, a former Navy base in the Bay Area continues to carry that nuclear legacy.

Residents were recently informed by the San Francisco Department of Health that a test taken in November 2024 at the former site of Hunters Point Naval Shipyard showed radiation levels of airborne plutonium-239 had exceeded the Navy's "action level," requiring the military to investigate.

The city and the residents were not informed until 11 months after that initial reading.

Hunters Point, a 500-acre peninsula jutting out into San Francisco Bay, served as a military laboratory to study the effects of nuclear weapons from 1946-69 after World War II. Although the research largely focused on how to decontaminate U.S. warships and equipment targeted with atomic bombs, the experimentation left much of the shipyard laced with radioactive contaminants and toxic chemicals.

For the last 30 years, the Navy has sought to clean up the area - now a U.S. Superfund site with the long-term goal of developing it into housing and parkland.

But some Bay Area community leaders say haphazard remediation work and lackluster public outreach have endangered the health and safety of residents of the Bayview-Hunters Point neighborhood that sits beside the former shipyard. And they point to the Navy's nearly yearlong delay in informing them of the elevated plutonium-239 reading, taken in November 2024, as just the latest example.

Plutonium-239 is a radioactive isotope and byproduct of nuclear bomb explosions. The elevated readings from November 2024 came from a 78-acre tract of land on the northeast portion of the shipyard, known as Parcel C.