The US Navy detected high levels of the radioactive isotope plutonium-239 at the Hunters Point Naval Shipyard about a year ago, and the city of SF is wondering why they didn’t get around to informing us until just now.  

When we see today’s alarming headline on NBC Bay Area saying “High levels of plutonium detected in San Francisco's Hunters Point,” our first question would be… okay, what is plutonium? Plutonium is a man-made element used in nuclear weapons and nuclear reactors, and it is highly toxic and radioactive. And it’s the latest toxic material detected at the longtime chemically beleaguered Hunters Point Shipyard. This discovery is all the more unnerving in light of Mission Local's report that that US Navy did not notify San Francisco officials of this radioactive presence until 11 months after they detected the airborne plutonium levels.

As a reminder, the US Navy ran the Hunters Point Naval Shipyard from 1945-1974, and conducted radioactive testing there after World War II. Now there are hundreds of people living there, though the site has been dogged by proof of toxic waste contamination for years. So the SF Department of Public Health is pretty alarmed that it took 11 months for the Navy to notify the city that they detected plutonium (specifically, the isotope Pu-239) at double the amount of what is considered the “Action Level” that should trigger further investigations.

“According to information recently shared with SFDPH, the November 2024 air monitoring result for Pu-239 approximately exceeded twice the Action Level concentration,” the DPH said in a letter to the US Navy obtained by Mission Local. “The City and County of San Francisco is deeply concerned by both the magnitude of this exceedance and the failure to provide timely notification.”

We should note that while these are double the plutonium levels that should have set off alarms, Mission Local spoke to a UC Berkeley nuclear physics professor who said it would take 1,000 times that so-called Action Level to cause cancer or radiation poisoning.

According to NBC Bay Area, the Navy and SFDPH officials are scheduled to meet today to discuss the contamination levels. The DPH is also asking for more information on specifically where the plutonium was detected in the air, and how long these higher-than-acceptable levels of plutonium have been detected.

We don’t have the details of that meeting yet, though those may soon become public. The US Navy’s Director of the Base Realignment and Closure Program Management Office West, Anthony Megliola, said in a statement to NBC Bay Area that the Navy would be "transparently sharing the information we have compiled, which demonstrates no threat or risk to human health or the environment."

Related: $6.3 Million Settlement Awarded to Hunters Point Homeowners Over Toxic Waste [SFist]

Image: Hunters Point Naval Shipyard crane. (Getty Images)