Dangerous Radiation Levels Detected in San Francisco

The San Francisco Health Department is sounding the alarm over high levels of radioactive plutonium-239 (Pu-239) detected in the air in Hunters Point Naval Shipyard. Plutonium 239 is a radioactive metal used for nuclear weapons and has been linked to lung disease and cancer.

Thursday, San Francisco's Health Officer, Susan Phillip, sent a letter to Navy leaders expressing concerns and asking for more information from the Navy. Phillip wrote that the Navy documented "exceedance of the plutonium-239 (Pu-239) air monitoring Action Level at Hunters Point Shipyard (HPS), Parcel C" in November of 2024. However, Phillip noted the Navy did not alert the city about this high level of Pu-239 until this month.

The letter from the health department reads in part, "San Francisco is deeply concerned by both the magnitude of this exceedance and the failure to provide timely notification. Such a delay undermines our ability to safeguard public health and maintain transparency.”

The Navy has agreed to meet with San Francisco officials on Friday to discuss the contaminant levels and how they were reported. In her letter, Phillip also asked that the Navy provide additional information to the city by November 7, including information on where and how long these high levels of Pu-239 were detected.

Anthony Megliola, the Navy's Director of the Base Realignment and Closure Program Management Office West, explained in an email to NBC Bay Area that the Navy will provide more information following its meeting with SFDPH on Friday.

Megliola said at that meeting, the Navy will be "transparently sharing the information we have compiled, which demonstrates no threat or risk to human health or the environment. "

The Navy operated the shipyard from 1945 to 1974, and it’s responsible for cleaning radioactive elements to allow the city to move forward with a long-planned redevelopment of the area.

This concern over radioactive contaminant levels is the latest speedbump in the decades-long efforts to clean up the site. The Navy is actively working to clean up a portion of the site called Parcel C and is monitoring dust there for all kinds of contaminants, including radioactive ones. Navy documents explained that radioactive contaminants can be found at Parcel C because of materials "in the soil, nuclear fallout, and historical shipyard activities."

Navy testing earlier in 2025 did not find any levels of contaminants that exceeded "Action Levels," though the numbers did get close to Action Levels in May of 2025.

NBC Bay Area Investigative Reporter Jaxon Van Derbeken, who has been covering the cleanup efforts at Hunters Point for around a decade, explained, "This is really quite an extraordinary letter sent by [the city], raising these really considerable red flags."

"This is not the first time that tests have come back in ways that the Navy wasn’t necessarily anticipating," Van Derbeken noted.

Van Derbeken reported on how testing data in 2021 from Hunters Point found elevated levels of the radioactive isotope Strontium-90. Navy leaders told the community they considered that testing data to be unreliable and "skewed."

Van Derbeken also pointed out that Navy documents monitoring contaminants on Parcel C show contaminants at concentrations below zero, like at -0.5 or -1.

"When you have zero values or below-zero values, you wonder how they’re calibrating their equipment testing to account for negative values," Van Derbeken noted.