The infamous accident at Pennsylvania’s Three Mile Island power facility is typically the first meltdown that comes to mind when people think about nuclear disasters in America. While CNN has reported that it was the worst nuclear meltdown ever in the United States, they are wrong.

The under-reported nuclear meltdown at the Santa Susana Field Laboratory in the late 1950s was far worse, and in fact, it is the worst nuclear disaster in United States history.

The Santa Susana Field Laboratory is located a scant couple of miles from the city of Simi Valley and only about 30 miles from greater Los Angeles. The site was used by Rocketdyne for jet fuel testing and by the Atomic Energy Commission for nuclear power experiments.

The Sodium Reactor Experiment was designed to prove that nuclear power could be used to generate commercial power. Sodium, which explodes on contact with water, was used to cool the reactor. On July 12, 1959 that experiment went horribly wrong, and there was no one around to report on it.

For 14 days, radioactive material was vented into the open air. There is no record as to exactly how much or what kind, though there are sources that say it was immeasurable because the measuring equipment that was available at the time did not have the ability to read emissions that high. What is known, is that deadly plutonium and strontium were indeed released during the episode.

This experiment took place before the widespread adoption of containment domes for nuclear power plants, and thus the radioactive material fell out unrestrained, to wherever the winds and air currents carried it. Some experts claim, based on a five-year study, that the amount of radiation released over the San Fernando Valley was 459 times that which was released at Three Mile Island.

The U.S. Department of Energy and Boeing, the current owner of the land, both play down the incident, with the DOE claiming not to know how much, if any, radiation was released, while Boeing claims a lack of elevated incidents of cancer in the employees that work in the area.

A study released by the UCLA School of Public Health in 2006 refutes those claims, and demonstrates that those who were exposed to radiation had more occurrences of key cancers than did those workers who experienced less exposure to the radiation.

Boeing has done its best to hamper the study by not providing their data about the prevailing wind currents at the time of the radioactive venting.

To this day, the site has yet to be cleaned up of the various contaminants, and the State of California has resisted allowing the Environmental Protection Agency to designate it as a Superfund site.

Today, the land is also contaminated with at least 500,000 gallons of trichloroethylene (TCE), in addition to a massive cocktail of radionuclides that includes plutonium and strontium according to the EPA.

California did pass Senate Bill 990 that requires the site be cleaned up to meet agriculture and residential requirements, and this cleanup is supposed to be completed by 2017. However, with various parties dragging their feet and complaining about the bill being too strict, it may take many years longer for the site to meet those requirements.

One of the biggest questions that remains is: ‘Who would actually want to live on a place, or eat food grown in a place carrying the chemical and radiation history of the Santa Susana Field Laboratory?’

Other U.S. Nuclear Meltdowns

Unfortunately, Three Mile Island and the meltdown at the Santa Susana Field Laboratory are not the only nuclear meltdowns that have occurred on US soil since the dawn of the nuclear age.

The Borax-I was a deliberate meltdown in 1954 at the Idaho National Laboratory (INL) that produced an explosion audible from at least a half mile away.

On Nov. 29, 1955, the EBR-I, also located at the INL, suffered a meltdown due to “operator error” during a coolant flow test.

On Jan. 3, 1961, the Army’s Stationary Low-Power Reactor No. 1 experienced an explosive meltdown that killed three military personnel. This prototype reactor, meant to provide electricity and heat in places like the Arctic, was built at the INL. According to one account, not all of the men died immediately.

The SNAP8ER at the Santa Susana Field Laboratory was allowed to run for about a year between 1964 and 1965 while in a compromised state, which resulted in approximately 80 percent of its fuel being damaged.

In 1966, the FERMI 1 reactor suffered a meltdown that resulted in a manual shutdown. Two of the fuel rods had melted, and according to the United States Nuclear Regulatory Commission, no radiation escape the containment area.

The SNAP8DR at the Santa Susana Field Laboratory suffered a fate that was about the same as the SNAP8ER. When it was shutdown in 1969, about 30 percent of its fuel was found to be damaged.

It should also be noted that the above list contains only those nuclear accidents that were considered meltdowns. There are still people in Utah today that are suffering ill affects from being downwind of the nuclear tests conducted in Nevada — some that went ‘right’ and some that went terribly wrong.