CBG Statement on the Navy’s Airborne Plutonium-239 Detection at Hunters Point

Earlier this month, the Navy confirmed a detection of airborne plutonium-239, the same isotope used in nuclear weapons, at its Hunters Point Naval Shipyard in San Francisco. The finding came from an air-filter sample collected on Parcel C during asphalt-grinding operations and measured roughly twice the federal action level for airborne plutonium.¹ Inexplicably, the Navy waited almost a year before notifying San Francisco’s Department of Public Health, a delay that should revive scrutiny of how the cleanup is being managed. 

The Navy insists there is no immediate danger, but the discovery is hard to ignore. Plutonium- 239 has a half-life of more than 24,000 years and emits alpha radiation that becomes hazardous when inhaled or ingested.  As Haakon Williams, CBG’s Executive Director notes, “Plutonium-239 is not found in the natural world. It is a man-made, extraordinarily poisonous substance.” Williams goes on to note, “According to the well-respected Institute for Energy and Environmental Research, as little as a millionth of an ounce of plutonium-239 inhaled into the lung can cause cancer with statistical near-certainty.”

The appearance of plutonium-239 in air filters at Hunters Point shows that radioactive particles were suspended in the air and not safely locked away in the ground as residents have long been promised. Perhaps more troublingly, the Navy’s failure to promptly alert regulators and the public of the elevated detection is a brazen violation of its own workplan, which states that air monitoring data will be shared with regulators on a bi-weekly basis, and shows that the Navy is willing to endanger the health of local residents to protect its own interests.² The Navy has still not uploaded the air monitoring report for November 2024, when the Pu-239 was detected, to its Hunters Point website, though reports for later months are.

CBG’s President, Anthony Zepeda, sums it up this way: “Plutonium is exceptionally hazardous because a particle too small to see can embed in the lung and irradiate tissue for the rest of a person’s life. Finding it in the air is a serious concern because there is no such thing as an acceptable level of airborne plutonium.”

Hunters Point is already one of California’s most contaminated sites, scarred by decades of Cold War radiological and industrial activity. Soil and sediment at the shipyard contain radioactive isotopes, heavy metals, and chemical waste. Plans to transform the property into thousands of new homes and parks continue to advance, but the presence of airborne plutonium illustrates that buried contamination can still become mobile when disturbed.

CBG has long critiqued the Navy’s plans to not clean up the contaminated soil but instead just cover contamination with thin layers of soil and asphalt that will be torn up during the planned redevelopment.³ If the Navy is allowed to abandon contamination at Hunters Point like this, there will very likely be many more detections of radioactivity, putting the safety of workers and residents at risk. Exposure to dangerous radioactive poisons should not be a cost of doing business, and this plutonium detection raises new questions about safety for workers and the community.

CBG has tracked Hunters Point for years; this latest episode underscores our worst concerns, that there are severe flaws in the Navy’s cleanup that have still not been resolved. CBG’s analysis has found that large portions of the site were never adequately tested and that the Navy is using outdated and shockingly weak cleanup standards.⁴

The full extent of contamination at some 90% of the Hunters Point property remains unknown. Of the 10% of the property that has been characterized, the Navy intends to declare much of the pollution acceptable to leave not cleaned up under its hugely inflated cleanup levels and soil and asphalt “covers.” The U.S. EPA, City and County of San Francisco, and other public agencies have inexplicably signed off on the Navy’s approach. 

The situation at Hunters Point is completely unacceptable, especially considering that workers will be digging into the Navy’s polluted soil, and future residents will be living atop a Superfund site that never really got cleaned up. The lackadaisical approach to protecting public health at Hunters Point is also troubling for the surrounding Bayview-Hunters Point community (largely low-income). The community has lived beside shipyard pollution for generations. Allowing radioactive material to remain buried beneath land slated for new housing is disturbing in more ways than one and continues a long pattern of unequal environmental risk.

This is not the first time the Navy has inappropriately waved away troubling radiation detections at Hunters Point. In 2021, the Navy admitted that its retesting of Parcel G had found exceedances of the dangerous radionuclide strontium-90, but did not disclose the full extent of the exceedances until later. The Navy manipulated its testing method for Sr-90 multiple times until no Sr-90 was detected above the remediation goal. Strontium-90 is dangerous because the body mistakes it for calcium and stores it in bones, where it can stay for decades and greatly raise the risk of bone cancer and leukemia, especially in children, whose bones are still developing.

The Navy’s response, rather than ordering the cleanup of those areas, was to dismiss valid results, alter testing methods mid-process, and keep the public in the dark. As Alex Dodd, CBG’s Assistant Director notes, “strontium-90 contamination at Hunters Point is being profoundly underestimated and inadequately addressed by the Navy. This undermines both public health protection and CERCLA’s core requirement of remedy protectiveness.” CBG’s prior analysis shows that the Navy’s Sr-90 cleanup standard is approximately 783 times weaker than the applicable EPA preliminary remediation goals.⁵ Despite the earlier scandalous revelation of alleged fraudulent soil sampling by Tetra Tech, the Navy decided to restrict retesting to about 10% of locations.

1. San Francisco Department of Public Health, “Request for Information Regarding Plutonium-239 Air Monitoring Exceedance at Parcel C,” pdf p. 7.
2. Parcel C Removal Site Evaluation Workplan, pdf p. 1761.
3. Committee to Bridge the Gap, From Cleanup To Coverup, August 2019.
4. Committee to Bridge the Gap, The Great Majority of Hunters Point Sites Were Never Sampled for Radioactive Contamination, October 2018; Committee to Bridge the Gap, Hunters Point Shipyard Cleanup Used Outdated and Grossly Non-Protective Cleanup Standards, October 2018.
5. Committee to Bridge the Gap, Hunters Point Shipyard Cleanup Used Outdated and Grossly Non-Protective Cleanup Standards, October 2018, pdf p. 19