San Francisco\u00a0\u2014\u00a0More than a half century after the U.S. ignited 67 atomic weapons in the the central Pacific Ocean, a former Navy base in the Bay Area continues to carry that nuclear legacy.<\/p>\n
Last week, residents were 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\u2019s \u201caction level,\u201d requiring the military to further investigate. <\/p>\n
The city and the residents were not informed until 11 months after that initial reading. <\/p>\n
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 following 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.<\/p>\n
For the last 30 years, the Navy has sought to clean up the area \u2014 now a U.S. Superfund site \u2014 with the long-term goal of redeveloping it into new housing and parkland. <\/p>\n
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\u2019s nearly year-long delay in informing them of the elevated Plutonium-239 reading, taken in November 2024, as just the latest example.<\/p>\n
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.<\/p>\n
\u201cThe City and County of San Francisco is deeply concerned by both the magnitude of this exceedance and the failure to provide timely notification,\u201d wrote San Francisco Health Officer Susan Philip in an Oct. 30 letter to Navy officials.<\/a> \u201cSuch a delay undermines our ability to safeguard public health and maintain transparency. Immediate notification is a regulatory requirement and is critical for ensuring community trust and safety.\u201d<\/p>\n Navy officials and some health experts insist the radiation levels detected at the site, while above the Navy\u2019s action level, did not pose an imminent or substantial threat to public health. Exposure to this level of Plutonium-239 every day for one year would be less than one-tenth the dose of radiation from a chest X-ray, according to a Navy spokesperson. <\/p>\n \u201cThe San Francisco Department of Public Health\u2019s letter references a single outlier air sample that detected Plutonium-239 above the regulatory action level,\u201d a Navy spokesperson said in a statement to The Times. \u201cRegulatory action levels are deliberately and conservatively established below levels of health concern, and a single detection of Pu-239 at this level does not pose a risk to human health or public safety.\u201d<\/p>\n The Navy said it has collected more than 200 ambient air monitoring samples from Parcel C since it began performing fieldwork there in 2023. The November 2024 sample was the only reading with elevated Plutonium-239, the Navy spokesperson told The Times. <\/p>\n Plutonium isotopes emit alpha radiation that is relatively benign outside the body, because it cannot travel through solid objects. However, if these radioactive particles are inhaled, they can damage the lungs and increase the long-term risk of developing certain cancers, according to the Centers for Disease Control and Prevention. <\/p>\n \u201cWhat we generally are concerned about for alpha emitters is if you get them into your body, and either through inhalation, ingestion, inadvertent injection \u2014 like somebody gets a cut and it gets into their body,\u201d said Kathryn Higley, a professor of nuclear science at Oregon State University. <\/p>\n But it\u2019s the lack of transparency and the 11-month delay in reporting the reading that has fomented community mistrust and raised questions regarding the military\u2019s competency to safely clean up the polluted shipyard. In 2000, the EPA admonished naval officials<\/a> for neglecting to inform residents that a fire had broken out at a hazardous landfill at Hunters Point. In 2017, two employees of the consulting firm Tetra Tech, who were hired by the Navy to assess radiation levels at Hunters Point, pleaded guilty to falsifying data<\/a> in an effort to avoid having to perform additional cleanup on some areas of the shipyard. <\/p>\n The presence of radioactive air contaminants \u2014 at any level \u2014 compounds the health risks of the Bayview-Hunters Point neighborhood, which already faces high exposure to toxic diesel particles from big rigs traveling on nearby freeways and cargo ships visiting the Port of San Francisco. <\/p>\n Hunters Point Biomonitoring Foundation, a local nonprofit, has found concerning levels of toxic substances in urine screenings it has provided to several residents of the neighborhood, especially among older individuals and those living closer to the former Naval shipyard.<\/p>\n \u201cNow, you\u2019re talking about adding one of the most devastating radionuclides known to the human cardiopulmonary system to the chemical burden,\u201d said Dr. Ahmisa Porter Sumchai, the foundation\u2019s medical director and principal investigator. <\/p>\n \u201cThe particulate load is enough to kill people,\u201d Sumchai added. \u201cBut you add … a little Plutonium-239, and it\u2019s a recipe for death.\u201d <\/p>\n Philip, the San Francisco health officer, said in a statement that she met with Navy officials Oct. 31 and received assurances that air and dust monitoring is \u201congoing\u201d and that the military agency is \u201creviewing their duct control methods to ensure they are fully protective of public health.\u201d<\/p>\n As a result, \u201cno immediate action is required from a public health safety standpoint,\u201d she said, adding that her office will continue to closely monitor the situation.<\/p>\n Other experts argued the situation was overblown. Phil Rutherford, a radiological risk expert and corporate consultant, called the delayed notification \u201cunacceptable\u201d but said the San Francisco health department\u2019s letter was \u201ca storm in a teacup<\/a>\u201d considering the low levels of radioactive material.<\/p>\n Higley, the Oregon State professor, said the site\u2019s long history of delays and scandals likely added to backlash from community members. \u201cI understand [residents\u2019] frustration that they want to see this place cleaned up so that they can safely use it,\u201d Higley said. \u201cAnd there\u2019s been a lot of reasons for why this process takes so long. But, from a radiological perspective, the actual residual radioactivity at the site is pretty modest.\u201d<\/p>\n In November 2024, a Navy contractor was grinding asphalt on the site \u2014 a construction project that, while unrelated to the site\u2019s historical contamination, triggered the Navy to monitor for any air quality issues. One of its air samplers, in Parcel C \u2014 collected 8.16 times 10\u201015 picocuries per milliliter of Plutonium-239 \u2014 twice the established action level \u2014 according to a Navy spokesperson. <\/p>\n Navy officials sent the sample to a lab for analysis, and the initial results came back in March 2025, showing high radiation levels. In April, they ordered the lab to reanalyze the sample. In the follow-up analysis, radiation levels of Plutonium-239 were below action levels.<\/p>\n Between May and September, the Navy \u201cfurther investigated the test results and conducted a methodical review of the laboratory\u2019s procedures and practices to ensure they complied with standards,\u201d according to the Navy spokesperson. \u201cA third party also conducted an analysis of the lab\u2019s performance.\u201d<\/p>\n Later that September, the Navy told the U.S. Environmental Protection Agency and several California state agencies about the elevated airborne radiation from Plutonium-239, in preparation for an upcoming community meeting. That information later trickled down to the San Francisco health department. <\/p>\n At some point, the Navy published some air quality data for Parcel C gathered between October and December 2024 on a website<\/a> where it curates several environmental monitoring reports. That report<\/a> only showed the lower Plutonium-239 radiation levels from the reanalysis were below the action level.<\/p>\n A Navy spokesperson told The Times that it was \u201cmistakenly uploaded.\u201d<\/p>\n \u201cAs soon as the Navy realized an incomplete report was uploaded, it was removed from the website,\u201d the spokesperson said, while the Navy worked to verify the results. <\/p>\n All that has contributed to the confusion and concern among locals and advocates alike. Navy officials are expected to attend a Hunters Point Shipyard Citizens Advisory Committee Meeting on Nov. 17. <\/p>\n When fieldwork is occurring at the shipyard, the Navy monitors for Plutonium-239 and several other radioactive elements that may have resulted from historic fallout from atomic weapons testing. <\/p>\n Acquired by the Navy in 1940, Hunters Point was initially a base where ships were built, repaired and maintained during World War II. After the war ended, it became home to the Navy Radiological Defense Laboratory, a military research facility dedicated to investigating the effects of nuclear weapons and radiological safety.<\/p>\n