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Nuclear Concerns : Aftermath of Sendai Earthquake and Tsunami

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Earthquake and Tsunami damage-Fukushima Dai Ic...Image by DigitalGlobe-Imagery via FlickrHow are the Filipinos in Japan doing after the earthquake?
As of its March 14, 2010 advisory, the Department of Foreign Affairs (DFA) is closely coordinating with its Embassy in Tokyo, Consulates, the Filipino community in Japan, and the Japanese government, to ensure the welfare of Filipinos. The Philippine Consulate-General is in Osaka while there are four honorary consuls in Sapporo, Morioka, Nagoya, and Naha.
According to the Japanese authorities, the hardest hit prefectures are Iwate, Fukushima and Miyagi, which are all located in the Tohoku Region in North Eastern Japan. There are approximately 4,500 Filipinos in that region.
Communication lines in the Tohoku region are still down, and transportation lines are also heavily affected.
Most affected areas:
PrefectureMost affected townsFilipino Population
IwateOfunato, Rizuken Takata909
MiyageWakabaya-shi, Kesennuma1,309
FukushimaIwaki, Shirakawa, Sukugawa, and Soma2,366
Nuclear Power in Japan
There are a total of 63 nuclear reactors throughout Japan: 52 are operational, five are under construction, four are currently shutdown and two have been under long-term shutdown.
The Fukushima Power Plant
Opened in March 26, 1971, the Fukushima Dai-Ichi Nuclear Power Plant, operated by the Tokyo Electric Company (TEPCO), is located in the town of Okuma, 150 miles northeast of Tokyo and 40 miles from the earthquake’s epicenter off the coast of the Tohoku region. The plant’s six boiling water reactors were built from 1970 to 1976.
How did the Fukushima Nuclear Power Plant incident happen?
Per the standard operating procedure, the earthquake and a series of aftershocks shut down the nuclear power stations at Fukushima. Some emergency generators activated but failed soon thereafter. These in turn stopped the cooling mechanism, which resulted in a continuous increase in pressure and heating of the Nuclear Reactors. This led to a build up of hydrogen as a by-product of the inability of the cooling system to function properly, resulting in the explosions in plant Units 1, 2, and 3.
Timeline:
At 2:48 PM on March 11, turbines and reactors of the Fukushima Nuclear Power Station Unit 1, 2, and 3 automatically shutdown due to the Sendai Earthquake.
Since the shutdown, the radioactive materials measured by the monitoring car have been increasing. A rise in the measured value has also been noted in one of the monitoring posts. Furthermore, at 3:29 PM on March 12, the radiation dose measured at site boundary had exceeded the limiting value. At 4:17 PM, of the same day, it was determined that a specific a “nuclear emergency” had occurred.
Late Saturday night, March 12, TEPCO officials said the explosion occurred in a structure housing turbines near the Unit 1 reactor at the plant rather than inside the reactor itself.
The national government instructed the evacuation of local residents within a 20km radius of the periphery. The operator trapped in the crane-operating console of the exhaust stack was transferred to the ground at 5:13 PM and confirmed dead at 5:17 PM.
As of March 14, officials confirmed a second hydrogen explosion at Unit 3. However, TEPCO said radiation levels at Unit 3 were 10.65 microsieverts, significantly under the 500 microsieverts at which a nuclear operator must file a report to the government.
On March 15, a third blast damaged the roof of Unit 2, as engineers struggled to contain the possible release of radiation amid efforts to prevent meltdowns in three of the plant’s four nuclear reactors.
A fire broke out at Unit 4 but was quickly extinguished according to TEPCO officials.
However, chief government spokesman Yukio Edano said, “There is no doubt that unlike in the past, the figures are the level at which human health can be affected.”
He said radioactive substances might spread outside the 20-30km area but would dissipate the farther they spread. The wind in the region is forecast to blow inland for most of today.
Additionally, Japan’s nuclear safety committee said radiation levels of 400 millisieverts an hour had been recorded near Fukushima’s No.4 reactor earlier today. Exposure to over 100 millisieverts a year is a level, which can lead to cancer, said the World Nuclear Association.
A second earthquake, measuring six on the Richter scale, hit Japan on March 15 although authorities are reportedly not anticipating significant damage.
Will there be a Nuclear Explosion?
No. It is impossible for the Fukushima nuclear reactor to explode like an atomic bomb. Only extremely enriched uranium fuel can induce an uncontrolled chain reaction resulting in a nuclear explosion. This is much more than the 4% 235U present in regular commercial nuclear reactor fuel used in Fukushima.
In general, a nuclear meltdown would occur if the reactor loses its coolant. This causes the reactor or part of it to melt. Without coolant, temperature in the core reactor rises to high enough levels that fuel rods become liquefied. If the temperature continues to rise, the steel walls of the reactor would also melt.
In a complete reactor meltdown, the molten uranium fuel rods would melt through the bottom of the reactor and sink into the earth beneath the power plant. The molten uranium would then react with groundwater, producing large explosions of radioactive steam and debris that may affect nearby towns and population centers.
What are the risks in case a meltdown occurs at Fukushima?
If the reactors do experience a meltdown, several types of radioactive materials could be expelled into the environment:
  • Cesium-137 and Strontium-90 present long-term environmental hazards and can be absorbed throughout the body, particularly the bones.
  • Plutonium-239 exposure often leads to lung cancer, and has a half-life of 24,000 years. (A half-life is the amount of time it takes for half of the radioactive isotopes in a substance to decay.) But (3) iodine-131 is one of the most dangerous materials that could come out of the reactors. Iodine has a relatively short half-life of about a week, but it can do massive amounts of damage in that time. It will most likely escape in gas form, which makes it easy to pick up, and the body rapidly funnels it to the thyroid, where it can accumulate and cause cancer in a relatively short amount of time.
Is there a cure in case of exposure?
For radioactive iodine (Iodine-131) exposure, potassium iodide pill may be taken before exposure or immediately after exposure. The iodine in the pill will flood the body and, importantly, the thyroid. Once this occurs, even though your body will absorb radioactive iodine, it will not be able to collect in the thyroid. Instead, this will be excreted from the body. If the pill is taken four (4) hours after exposure, there is a 50 percent chance of surviving thyroid cancer. Prophylactic potassium iodide was first used with great success during the Chernobyl disaster in 1986.
As for exposure to Cesium-137, Prussian blue is the antidote.
Have there been major Nuclear power plant incidents in the past?
Two of the most well-known nuclear accidents occurred at the Three Mile Island reactor Number 2 in the United States of America and the Chernobyl reactor Number 4 in the former Ukrainian Soviet Socialist Republic (now Ukraine), both of which involved human error.
What happened in the 1979 Three Mile Island disaster in the United States of America?
On March 28, 1979, on an island ten miles from Harrisburg, Pennsylvania, the Three Mile Island Nuclear Power Station experienced a partial reactor meltdown due to simple human error and the failure of a minor valve in the reactor. A partial nuclear meltdown happens when the uranium fuel rods start to liquefy, but do not fall through the reactor floor and breach the containment systems. Hydrogen gas also accumulated inside the reactor and caused an explosion, although the explosion did not damage the containment systems. Two weeks later the reactor was brought to a cold shutdown and the accident was over. No one was directly injured as a result of the accident. However, some radioactive gas and water were vented to the environment around the reactor. The accident is considered to be the worst nuclear disaster in U.S. history.
What happened in the 1986 Chernobyl disaster in the Ukrainian SSR?
On April 26, 1986, the Chernobyl nuclear power plant, located about 80 miles north of Ukraine, experienced what is considered as the worst reactor disaster in history. It was caused largely because of the suspension of normal reactor operations, as an experiment was to take place and normal safety guidelines were not met. It is seen as a result of many small mistakes adding up to the accident, which occurred when two rods shattered.
The Soviet government‘s lack of transparency in the aftermath of the disaster garnered criticism. No one outside the Soviet Union knew about the accident until two days later, when scientists in Sweden detected massive amounts of radiation being blown from the east. The effects of the disaster at Chernobyl were widespread. The World Health Organization (WHO) found that the radiation release from the Chernobyl incident was 200 times more than that of the Hiroshima and Nagasaki nuclear bombs combined. The radiation released also had long-term effects on the cancer incidence rate of the surrounding population. According to the Ukrainian Radiological Institute, over 2,500 deaths resulted from the Chernobyl incident.
Will the Fukushima Nuclear incident affect the Philippines?
On March 14, 2011, Philippine government authorities assured the public that there is no immediate threat to the Philippines. The DFA and the Department of Science and Technology-Philippine Nuclear Research Institute (DOST-PNRI) stated they are monitoring the situation in Fukushima, particularly the efforts of the Japanese Government to contain the damage.
If needed, there is an existing National Radiological Emergency Preparedness and Response Plan (RADPLAN) that will be executed by the National Disaster Risk Reduction Management Council (NDRRMC).
The RADPLAN establishes an organized emergency response capability for timely, and coordinated action of Philippine authorities in a peacetime radiological incident or emergency. Participating agencies such as the PNRI and the Office of Civil Defense (OCD) are given the authority and responsibility to coordinate the activities of other agencies involved. Advisories will be issued by the DOST-PNRI to update the public on developments.
What is President Aquino’s position on Nuclear Power?
Last March 2010, then-Senator Aquino submitted the following statements to the Philippine Daily Inquirer:
“I would rather exhaust other means than resort to nuclear power. We have other perceivably safer sources of renewable energy.”
“Nuclear energy has re-emerged as an option to satiate the world’s present and future electricity needs. However, it continues to face ‘social acceptability’ problems because of fears about the safety of its use. There are other sources of energy that have less chances of endangering the lives of people. In the case of the BNPP (Bataan Nuclear Power Plant), it has a large amount of documented safety hazards, and may pose as a threat to the safety and/or well-being of the residents around it.”
“The challenge for both government policymakers and private sector stakeholders lies in exploring and developing energy resources safely, economically and in an environmentally-responsible manner. The pace of developments must also be efficient and timely to meet forecast demand.”
“Neither renewables nor fossil fuels nor nuclear power alone can bring immediate ‘energy self-sufficiency.’ We must pursue an optimal mix of sources of energy immediately and aggressively if we hope to meet our future needs. The energy mix should be able to reduce risks associated with the supply, price volatility and production cost.”
“The government must also take an active role in pushing for a comprehensive competition policy.”
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