NRC Short History – Core Melt & Cooling System failure circa 1960s – the result : Fukushima

Why Fukushima happened. If the AEC had behaved according to its legal mandate in the 1960s and had the NRC recognised its failures in the 1970s, and had the Japanese authorities taken the safe view instead of the AEC view, Fukushima would never have spread its emissions over Japan and half the globe, come what may. The ECCS didn’t work, cores melted and containment failed and it was all foreseen and discounted at the very time Fukushima was being built. To meet US Strategic need. (presumably for a reserve source of plutonium)


The Problem of Core Meltdown

The regulatory staff sought to gain as much experimental data as possible to enrich its knowledge and inform its collective engineering judgment. This was especially vital in light of the many unanswered questions about reactor behavior. The AEC had sponsored hundreds of small-scale experiments since the early 1950s that had yielded key information about a variety of reactor safety problems. But they provided little guidance on the issue of greatest concern to the AEC and the ACRS by the late 1960s–a core meltdown caused by a loss-of-coolant accident.

Reactor experts had long recognized that a core melt was a plausible, if unlikely, occurrence. A massive loss of coolant could happen, for example, if a large pipe that fed cooling water to the core broke. If the plant’s emergency cooling system also failed, the build-up of “decay heat” (which resulted from continuing radioactive decay after the reactor shut down) could cause the core to melt. In older and smaller reactors, the experts were confident that even under the worst conditions–an accident in which the loss of coolant melted the core and it, in turn, melted through the pressure vessel that held the core–the containment structure would prevent a massive release of radioactivity to the environment. As proposed plants increased significantly in size, however, they began to worry that a core melt could lead to a breach of containment. This became their primary focus partly because of the greater decay heat the larger plants would produce and partly because nuclear vendors did not add to the size of containment buildings in corresponding proportions to the size of reactors.

The greatest source of concern about a loss-of-coolant accident in large reactors was that the molten fuel would melt through not only the pressure vessel but also through the thick layer of concrete at the foundation of the containment building. The intensely radioactive fuel would then continue on its downward path into the ground. This scenario became known as the “China syndrome,” because the melted core would presumably be heading through the earth toward China. Other possible dangers of a core meltdown were that the molten fuel would breach containment by reacting with water to cause a steam explosion or by releasing elements that could combine to cause a chemical explosion. The precise effects of a large core melt were uncertain, but it was clear that the results of spewing radioactivity into the atmosphere could be disastrous. The ACRS and the regulatory staff regarded the chances of such an accident as low; they believed that it would occur only if the emergency core cooling system (ECCS), made up of redundant equipment that would rapidly feed water into the core, failed to function properly. But they acknowledged the possibility that the ECCS might not work as designed. Without containment as a fail-safe final line of defense against any conceivable accident, they sought other means to provide safeguards against the China syndrome.

The Emergency Core Cooling Controversy

At the prodding of the ACRS, which first sounded the alarm about the China syndrome, the AEC established a special task force to look into the problem of core melting in 1966. The committee, chaired by William K. Ergen, a reactor safety expert and former ACRS member from Oak Ridge National Laboratory, submitted its findings to the AEC in October 1967. The report offered assurances about the improbability of a core meltdown and the reliability of emergency core cooling designs, but it also acknowledged that a loss-of-coolant accident could cause a breach of containment if ECCS failed to perform. Therefore, containment could no longer be regarded as an inviolable barrier to the escape of radioactivity. This represented a milestone in the evolution of reactor regulation. In effect, it imposed a modified approach to reactor safety. Previously, the AEC had viewed the containment building as the final independent line of defense against the release of radiation; even if a serious accident took place the damage it caused would be restricted to the plant. Once it became apparent that under some circumstances the containment building might not hold, however, the key to protecting the public from a large release of radiation was to prevent accidents severe enough to threaten containment. And this depended heavily on a properly designed and functioning ECCS.

The problem facing the AEC regulatory staff was that experimental work and experience with emergency cooling was very limited. Finding a way to test and to provide empirical support for the reliability of emergency cooling became the central concern of the AEC’s safety research program. Plans had been underway since the early 1960s to build an experimental reactor, known as the Loss-of-Fluid-Tests (LOFT) facility, at the AEC’s reactor testing station in Idaho. Its purpose was to provide data about the effects of a loss of coolant accident. For a variety of reasons, including weak management of the test program, a change of design, and reduced funding, progress on the LOFT reactor and the preliminary tests that were essential for its success were chronically delayed. Despite the complaints of the ACRS and the regulatory staff, the AEC diverted money from LOFT and other safety research projects on existing light-water reactor design to work in the development of fast-breeder reactors. A proven fast breeder was an urgent objective for the AEC and the Joint Committee; Seaborg described it as “a priority national goal” that could assure “an essentially unlimited energy supply, free from problems of fuel resources and atmospheric contamination.”

To the consternation of the AEC, experiments run at the Idaho test site in late 1970 and early 1971 suggested that the ECCS in light-water reactors might not work as designed. As a part of the preliminary experiments that were used to design the LOFT reactor, researchers ran a series of “semiscale” tests on a core that was only nine inches long (compared with l44 inches on a power reactor). The experiments were run by heating a simulated core electrically, allowing the cooling water to escape, and then injecting the emergency coolant. To the surprise of the investigators, the high steam pressure that was created in the vessel by the loss of coolant blocked the flow of water from the ECCS. Without even reaching the core, about 90 percent of the emergency coolant flowed out of the same break that had caused the loss of coolant in the first place.

In many ways the semiscale experiments were not accurate simulations of designs or conditions in power reactors. Not only the size, scale, and design but also the channels that directed the flow of coolant in the test model were markedly different than those in an actual reactor. Nevertheless, the results of the tests were disquieting. They introduced a new element of uncertainty into assessing the performance of ECCS. The outcome of the tests had not been anticipated and called into question the analytical methods used to predict what would happen in a loss-of-coolant accident. The results were hardly conclusive but their implications for the effectiveness of ECCS were troubling.

The semiscale tests caught the AEC unprepared and uncertain of how to respond. Harold Price, the director of regulation, directed a special task force he had recently formed to focus on the ECCS question and to draft a “white paper” within a month. Seaborg, for the first time, called the Office of Management and Budget to plead for more funds for safety research on light-water reactors. While waiting for the task force to finish its work, the AEC tried to keep information about the semiscale tests from getting out to the public, even to the extent of withholding information about them from the Joint Committee. The results of the tests came at a very awkward time for the AEC. It was under renewed pressure from utilities facing power shortages and from the Joint Committee to streamline the licensing process and eliminate excessive delays. At the same time, Seaborg was appealing–successfully–to President Nixon for support of the breeder reactor, and controversy over the semiscale tests and reactor safety could undermine White House backing for the program. By the spring of 1971, nuclear critics were expressing opposition to the licensing of several proposed reactors, and news of the semiscale experiments seemed likely to spur their efforts.

For those reasons, the AEC sought to resolve the ECCS issue as promptly and quietly as possible. It wanted to settle the uncertainties about safety without arousing a public debate that could place hurdles in the way of the bandwagon market. Even before the task force that Price established completed its study of the ECCS problem, the Commission decided to publish “interim acceptance criteria” for emergency cooling systems that licensees would have to meet. It imposed a series of requirements that it believed would ensure that the ECCS in a plant would prevent a core melt after a loss-of-coolant accident. The AEC did not prescribe methods of meeting the interim criteria, but in effect, it mandated that manufacturers and utilities set an upper limit on the amount of heat generated by reactors. In some cases, this would force utilities to reduce the peak operating temperatures (and hence, the power) of their plants. Price told a press conference on June 19, 1971 that although the AEC thought it impossible “to guarantee absolute safety,” he was “confident that these criteria will assure that the emergency core cooling systems will perform adequately to protect the temperature of the core from getting out of hand.”

The interim ECCS criteria failed to achieve the AEC’s objectives. News about the semiscale experiments triggered complaints about the AEC’s handling of the issue even from friendly observers. It also prompted calls from nuclear critics for a licensing moratorium and a shutdown of the eleven plants then operating. Criticism expressed by the Union of Concerned Scientists (UCS), an organization established in 1969 to protest misuse of technology that had recently turned its attention to nuclear power, received wide publicity. The UCS took a considerably less sanguine view of ECCS reliability than that of the AEC. It sharply questioned the adequacy of the interim criteria, charging, among other things, that they were “operationally vague and meaningless.” Scientists at the AEC’s national laboratories, without endorsing the alarmist language that the UCS used, shared some of the same reservations. As a result of the uncertainties about ECCS and the interim criteria, the AEC decided to hold public hearings that it hoped would help resolve the technical issues. It wanted to prevent the ECCS question from becoming a major impediment to the licensing of individual plants.

The AEC insisted that its critics had exaggerated the severity of the ECCS problem. The regulatory staff viewed the results of the failed semiscale tests as serious but believed that the technical issues the experiments raised would be resolved within a short time. It did not regard the tests as indications that existing designs were fundamentally flawed and it emphasized the conservative engineering judgment it applied in evaluating plant applications. But the ECCS controversy damaged the AEC’s credibility and played into the hands of its critics. Instead of frankly acknowledging the potential significance of the ECCS problem and taking time to fully evaluate the technical uncertainties, the AEC acted hastily to prevent the issue from undermining public confidence in reactor safety or causing licensing delays. This gave credence to the allegations of its critics that it was so determined to promote nuclear power and develop the breeder reactor that it was inattentive to safety concerns”. credit: shorthis.htm was reviewed for currency of material and updated (new Chapter 4 added) on Monday, January 10, 2000 by Sandy Joosten

As indeed it was. Indeed it is an attitude that nuclear industry insiders employed by the NRC today would like to amplify in the modern world.

Meanwhile the US Navy is on alert in part because Iran has constructed a single reactor fuel rod. Iranian scientists must feel as satified as Groves did.

The US and the rest of th world is very worried. How many fuel rods does Japan have?

Where are they and has the plutonium been extracted from spent ones? If yes, who has it? Is there a plutonium trail from Japan to other States outside obligation channels? (Apart from the contamination the AEC approved Fukushima reactors have spread over the planet.)

“Failure of containment”. In all senses. Did the USA really think that its actions in Japan would increase the chances of non proliferation ?

No “technical fix”.

What happens next?

More industry propaganda that the Fukushima disaster wasn’t one?

How many kilograms of Japanese plutonium is unaccounted for ? Both from releases from the flawed reactor disaster in March 2011 and deliberate diversion by nation states or third pary fall guys?

Do the current state of Iran-Japan relations undermine the strategic aims of the USA and the west as originally applied by the provision of nuclear reactors to Japan? Apart from increased production of plutonium, in what way did this policy advance US and Western interests?

Has the plan backfired? Is the world safer or in greater danger as a result of the construction of Japanese reactors? Does this rationale hold for every reactor on the planet? If the construction of one Iranian fuel rod is a threat to the interests of the USA and the West, how big are threat are thousands of fuel rods in existence globally?

What is to be done? Prepare for war, business as usual?

see also

6 Responses to “NRC Short History – Core Melt & Cooling System failure circa 1960s – the result : Fukushima”

  1. Whoopie Says:

    Well…there you have it. All pertinent questions that need to be asked. Esp this one:
    “If the constructi­on of one Iranian fuel rod is a threat to the interests of the USA and the West, how big are threat are thousands of fuel rods in existence globally? How many fuel rods does Japan have? AND Where are they?

    Next stop: Ba Ba Ba Ba…Bomb Iran.
    This morning on front page at HP, Santorium says he’d do JUST THAT. Bomb ’em. Wonder if that’s why O pulled all troops out of Iraq? Plans for war…

    The USA has gone bat shit crazy.
    TY Paul.

    • nuclearhistory Says:

      A Southland Tale was a doco

      Mandy Moore was pretty good at playing an actor who couldnt act.

  2. Whoopie Says:

    BTW in case you didn’t see it:
    Nuclear News Linked to you:

  3. Whoopie Says:

    Thought you might be interested in this Pro-Nukes response to your post just now.

    but I know where to look it up
    302 Fans Unfan
    4 minutes ago( 9:08 AM)
    Well, it’s pretty much establishe­d that there were no plutonium releases from the reactors, and you still haven’t addressed my question as to which yakusa is being accused of diverting nuclear materials.
    Do you have any evidence? Do you have any answers to these many questions?
    What if you don’t? What if you don’t like the answers?

    • nuclearhistory Says:

      Is this guy completely cut off? Ill go back and find the J gov announcement of neptunium and plutontium releases found up to 80 kms from memory from Fuk. As soon as it was announced and there was a response, the J gov announced it would no longer release Plutonium monitoring data.

      I will make a post answering this pillock’s questions.

  4. Whoopie Says:

    Alright!! The “Japanese Nuclear Energy Safety Organizati­on Executive Advisor” Emails to the Radiation Protection Unit of the Cook NPP in the US for help.
    As a consequenc­e, an engineer from Los Alamos is invited to open new markets for depleted uranium, which the US Army uses en masse.

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