Nuke crisis far from under control as TEPCO's 'inadequate predictions' continue
The crisis at the Fukushima No. 1 nuclear plant is far from over. I became certain of this when the power plant was opened to the media on Feb. 20, and witnessed the reality of what was going on inside. This, despite the government's declaration just two months prior, that the reactors had achieved a "cold shutdown" state, bringing the crisis "under control."
The invitation for journalists to inspect the plant in February was no doubt intended to drive home the impression that the disaster had indeed been resolved. However, the key element in the cooling system now in place appeared unstable and hastily thrown together, and high radiation levels were detected inside the plant. The plant was far from being "normal" or "under control."
On the morning of our visit, some 40 members of the press changed into white protective suits and entered the grounds on two buses. After stopping to look inside the quake-proof tower that serves as the recovery effort headquarters, we toured the plant grounds for about an hour by bus.
When we arrived at the waterfront, where the plant's No. 1-4 reactors are located, a nearby building's blown-out windows -- the result of a hydrogen explosion at the neighboring No. 1 reactor -- jumped out at us. The alarms on the radiation dosimeters we were wearing started going off, and an official from plant operator Tokyo Electric Power Co. (TEPCO) accompanying us yelled out, "100 microsieverts (0.1 millisieverts per hour)!"
Radiation levels inside the plant have dropped from those detected immediately after the crisis began. However, close to the No. 3 reactor, which still has the highest radiation levels inside the plant, the figure can reach 1.5 millisieverts. In other words, the amount of radiation one is exposed to by being near the No. 3 reactor for just one hour is equivalent to what a Japanese resident is exposed to in a whole year from background radiation.
The No. 4 reactor has relatively low radiation levels, and atop a hill some 300 meters southwest of it, we got out of our buses for 15 minutes. We could see several people working on the fourth and fifth floors of the No. 4 reactor building. The No. 3 reactor building was still just a tangle of steel from the reactor building's frame.
Our guide's voice was difficult to follow, as it was muffled by the same mask we all wore. Breathing with those masks was difficult, and seemed to exacerbate my exhaustion; I have nothing but respect for the workers who do their jobs wearing such equipment. Struck by the harsh conditions, I realized that mishaps that would not happen under normal conditions were more likely to occur here, and that extra care must be taken to avoid them.
While I believe it was TEPCO's intent to convince us that the disaster has been "resolved," the media inspection was limited to certain areas, citing "high radiation levels" in other parts of the plant. As for our "interview" of plant workers, three TEPCO-approved employees of a TEPCO subsidiary were prepared for us, with a TEPCO public relations official in tow.
What most struck me as dangerous was what we saw first -- the injection pumps located on a hill overlooking one of the reactors.
Currently, radiation-tainted water is sent through a purifying system before it is reused to cool down the No. 1, 2 and 3 reactors, which all suffered core meltdowns. In other words, the abovementioned injection pumps function like hearts, sending clean, cooling water to the reactors. The system was built in approximately three months following the outbreak of the disaster.
The pumps -- three of them -- were set up on the bed of a truck in a parking lot on a hill northwest of the No. 1 reactor. The pumps were covered with tarps, while pipes leading to the reactors were covered in black rubber insulation. Both are measures taken against freezing. I was shocked, however, to learn that both the tarp and the rubber insulation were put in place after water had already leaked due to freezing.
Low temperatures in January had caused the pumps and their surrounding pipes to freeze, leading to a series of water leakages. While the situation never deteriorated so far as to bring water injection to a complete stop, the incident exposed the vulnerability of the temporary equipment that has been installed. Water leaks due to freezing in the spent nuclear fuel pools of the No. 3 and No. 4 reactors and in a desalinating system for radiation-tainted water have also occurred. Cooling of the No. 4 reactor's fuel pool -- which holds 1,535 spent fuel rods, equivalent to what is used by two reactors -- was halted for approximately two hours.
Nuclear power plants have been running in the Fukushima area for over 40 years. Why hadn't countermeasures against the cold winters been taken earlier? Takeshi Takahashi, who became plant chief last December, said, "We believed that we had taken adequate steps against the freezing, especially with our most crucial facilities, but our predictions were inadequate."
Inadequate predictions or assumptions are precisely what caused the disaster in the first place. Based on a long-term evaluation of quake activity published by the government's Earthquake Research Committee in 2002, TEPCO released calculations in the spring of 2008 that "tsunami of up to 15.7 meters will hit (the Fukushima No. 1) plant." Subsequently concluding, however, that "such a tsunami will not actually take place," the utility failed to implement any tsunami countermeasures. Even now, with a crisis still unfolding, the company continues to act in the same way.
To the reporters visiting the plant, Takahashi tried to reinforce the government's assurances that a "cold shutdown" had been achieved, saying, "Almost a year after the disaster (began), the reactors are releasing less and less heat, and because we are consistently injecting them with water, they have been stabilized. Our facilities are equipped with various back-ups that even if something malfunctioned, we have a sufficient margin within which to deal with it."
However, whether the reactors are stable or not can only be determined right now using indirect circumstantial evidence such as temperature. Furthermore, one of the thermometers used to determine the so-called cold shutdown broke earlier this year. No matter how many emergency back-up measures TEPCO arms itself with, they mean nothing if the utility's fundamental predictions and assumptions are flawed. The latest series of water leaks is an indication of TEPCO's basic lack of vision and imagination. A year on, and we are still unable to ascertain what's actually happening inside those reactors. There is no more room for "inadequate predictions." (By Ei Okada, Science & Environment News Department)
Click here for the original Japanese story
(Mainichi Japan) March 16, 2012
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