The Santa Susana Field Laboratory.

Japan’s nuclear power crisis has planted indelible memories worldwide and revived doubts about the health and safety of nuclear power. It may unsettle many to discover that California, too, experienced a partial nuclear meltdown. The accident, which occurred in 1959, is claimed to have released more radiation than Three Mile Island. The severity of health impacts from this incident on site workers, and to the surrounding community, is still being debated to this day.

Listen to the QUEST radio story Nuclear’s Future in the U.S.

Don’t remember hearing about the accident? Not many do. Located in Ventura County, California, The Santa Susana Field Laboratory (SSFL) was a testing site for rockets and nuclear work during the dawn of the Cold War. As such, there was an experimental attitude and secrecy associated with this site as these technologies were being developed. The events at SSFL essentially lay hidden from the public for twenty years. It wasn’t until scares from the Three Mile Island disaster in 1979 ignited UCLA and reporters to unearth the nuclear accident at SSFL that the public first learned about the immensity of this meltdown.

The Sodium Reactor Experiment (SRE) was the first U.S. commercial nuclear power plant, and as such, was subject to untested “glitches” in operation. On July 13th, 1959, power within the SRE reactor rose uncontrollably, nearly tripling in less than eight seconds. Radiation monitors went off scale. After a difficult shutdown and inability to find the cause of the problems, workers restarted the damaged reactor and ran it for two more weeks before discovering that 13 of 43 fuel rods had partially melted. Workers determined that a blockage from a contaminating fluid in the coolant system caused the melting.

Fortunately, this reactor was only 1/100 the size of the Three Mile Island reactor. However, it’s been reported to have released up to 240 times more radiation than the 1979 disaster. How can this be? The answer: the experimental reactor did not have a concrete containment structure. Thus, any radiation that escaped the venting system entered the atmosphere.

When the Department of Energy came out in 1989 with the statement that the SSFL site was still contaminated, community concern began to grow. A study showing increased levels of bladder cancer nearby the site showed up. Then there was the follow up report by UCLA that SRE plant workers who had been exposed to the highest levels of radiation had triple the amount of cancer death rates then those not exposed.

Today, the nuclear plant is gone, but years of work cleaning up the site remain. In 2007, the EPA declared SSFL a Superfund site. After numerous lawsuits that ended with a large settlement to nearby residents, as well as community workshops and ongoing epidemiological studies, the jury is still out on just how much contamination from the SSFL site is attributable to the 1959 SRE accident. Because the types of radiation released can remain at dangerously high levels for centuries, the decisions made at Santa Susanna during the ’50s and ’60s may continue to affect residents for generations to come.

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California’s Historical Nuclear Meltdown 2 October,2015Kim Vincent


Kim Vincent

Kim Vincent is the QUEST Content Intern for the 2011 winter / spring term. Kim is a substitute teacher for Fremont Union High School District specializing in biology and physiology education. She has a degree in biochemistry from UC Davis as well as a M.S. in molecular, cellular, and integrative physiology from UC Davis. Currently, Kim is taking courses at De Anza College in film and electronic media. As an active member of her community, Kim has performed volunteer research with the Hopkins Marine Lab, UC Santa Cruz, and the Cal Academy of Sciences. Kim also coaches junior volleyball and enjoys hiking along the south and mid-peninsula.

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