The Worst Nuclear Meltdown in U.S. History – And You’ve Never Heard of It!

by on August 1, 2017 · 5 comments

in Energy, History

Santa Susanna Lab in Ventura County Suffered Meltdown 58 Years Ago

By Michael Steinberg / Black Rain Press

The worst meltdown in our history? And we’ve never heard of it?

That’s Right. Wikipedia characterizes the meltdown as “the worst in US history” and asserts “the radioactive releases are thought to be much more than at Three Mile Island in 1979.”

And where? Less than 30 miles from downtown Los Angeles and less than 20 miles from the Pacific Ocean.

July 2017 marks 58 years since this little known catastrophe, which occurred in July 1959 at the Santa Susanna Field Laboratory in Southern California’s Ventura county, not many miles north of LA county.

Santa Susanna became a site for developing US commercial nuclear reactors in the 1950s. Over those years 10 such experimental “low power” reactors, operated by Atomics International, ran them. One of them became the first nuke to produce electricity for a US municipality, Moorpark in 1957.

But on July 12, 1959, an experimental trial at another reactor went terribly wrong.

In his 2012 book, Mad Science, author Joseph Mangano, director of the Radiation and Public Health Project ( ) describes these events:

“temperatures climbed to levels much greater than during any of the other previous tests… A blazing-hot bull in a china shop now existed in the (nuclear) core… The fuel rods containing uranium pellets began to melt and large amounts of radioactive gases were formed.”

Operators couldn’t shut down the reactor until the next day. But instead of keeping it closed Atomics International ordered it restarted, meltdown and all, throughout the month. John Pace, a worker in the reactor, remembers –

“Starting the of the second day of the meltdown holding tanks (which hold radioactive releases until they are released into the environment) were full. They still didn’t know how much radiation we were dealing with-the (radiation) monitors went clear off the scale.”

“Each day for the next two weeks,” Mangano reported, ” radiation in the holding tanks was gradually released into the air. Pace recalls that the exercise took place every day, sometimes twice a day… the greatest concern among officials was which way the wind was blowing.” Pace told Mangano:

“They tried to make sure it was blowing towards the Pacific Ocean, instead of the San Fernando Valley, so it would affect fewer people.”

The reactor didn’t fully shut down until July 23. But this was hardly the end of the story. More radiation was released subsequently, blowing in the wind wherever. Atomics International told workers like John Pace to keep their mouths shut, and kept the meltdown from the public for decades.

Today it is still unclear who should clean up Santa Susanna, and what health problems it may have caused in surrounding communities.

On March 8 this year, KCBS TV Channel 2 in LA ran a story, “Concerned Parents Call For Full Cleanup of Toxic Santa Susanna Site.”

One of those parents, Melissa Bumstead, whose daughter has leukemia, told KCBS she documents cases of other rare cancers near the Santa Susana Field Laboratory. “We feel very strongly that there may be a pediatric cancer cluster surrounding the site that may be linked to the toxins,” she told the news channel.

Santa Susanna was also the site of a rocket development facility, whose rocket fuel and other toxic chemicals add to the poisonous stew that still haunts residents and former workers.

David Hirsch, director of the Program on Environmental and Nuclear Policy at UC Santa Cruz, told KCBS,

“There have been federally funded studies that indicate the rate of cancer is 60 percent higher closer to the (Santa Susanna) site than further away.”

Sources: Wikipedia,, Mad Science: The Nuclear Power Experiment, Joseph Mangano;  KCBS TV LA,

{ 5 comments… read them below or add one }

Frank Gormlie August 1, 2017 at 8:27 pm

Thanks Michael for bringing this buried story to us.


bodysurferbob August 1, 2017 at 8:31 pm

this is very f*cked up. how could this be?


Ol OB Hippie August 1, 2017 at 9:01 pm

The anti-nuclear movement in this country didn’t get off the ground really until the 1980s. San Diego had a very vibrant one. At t he peak of the local movement, thousands blocked the entrance to the Pt Loma nuclear sub base and dozens were arrested in non-violent civil disobedience.


G Roller February 21, 2020 at 9:49 am

I lived in Agoura Hills from 1973-77 and moved back in 1983-2017. And the idea of nuclear contamination at the Rocketdyne (Santa Susana Field Site) never was discussed until after 2001 – living 8 miles southwest of the clean-up.

I must have been one of the lucky people that attended LA Pierce College in 1960-62. Also, we never knew about the nuclear meltdown on July 1959.

We have to be aware of our surrounding environment where ever we live in Los Angles County.


sealintheSelkirks February 22, 2020 at 12:16 pm

And think about just how fast 3 Mile Island disappeared from the news.

For another ‘lost’ nuclear near-disaster, read the book ‘We Almost Lost Detroit’ by John G. Fuller 1975.

We are ALWAYS lied to by governments and the wealthy who own the corporations that own the governments. Always. And there is so much that we’ll never be allowed to find out…



Leave a Comment

Older Article:

Newer Article: