The catastrophe also knocked out the cooling system of the Fukushima Daiichi plant that has since spurred anxiety of nuclear widespread. Despite weeks of efforts to cool down the plant reactor using sea water, the plant still experienced continuous episodes of explosions and eventually released nuclear radiation to the vicinity.
Fukushima on par with Chernobyl
On 12 April, Japan upgraded its nuclear emergency to the highest level of 7 in the international scale of atomic crisis, putting it on par with the Chernobyl nuclear disaster that took place in 1986. Level 7 in the UN's International Events Scale (INES) is rated as a major accident that related to:
a ''Major release of radioactive materials with widespread health and environmental effects, requiring implementation of planned and extended countermeasures.''
The significance of INES scale from zero to Level 7 are shown below:
Zero: Events known as 'deviations' that have no safety significance
Level 1: Anomaly. Minor problem with safety components at a nuclear plant, but significant safety margin remaining.
Level 2: Incident. Radiation levels of more than 50 millisieverts (mSv) per hour.
Level 3: Serious Incident. Severe contamination within facility with non-lethal injuries. Low probability of public exposure.
Level 4: Accident with local consequences. Partial meltdown to fuel and release of significant amount of radioactive particles within facility but no countermeasures needed.
Level 5: Accident with wider consequences. Severe damage to reactor core, large quantity of radioactive material released. Requires some planned countermeasures.
Level 6: Serious accident. Significant release of radioactive material requiring planned countermeasures.
Level 7: Major accident. Major release of radioactive materials with widespread health and environmental effects, requiring implementation of planned and extended countermeasures.
----Borneo Post, 13/4/2011.
Plans to dismantle plant
Every increment in the scale would mean 10-fold increase in severity. Now, the options left are very limited. One of them would be to dismantle the plant for good. However, this is no ordinary dismantling, claimed Tokyo-based analyst at Mizuho Investors Securities Co.. The decommissioning of a nuclear plant would take not 3 years, but 3 decades to complete, consuming up to 1 trillion yen ($12 billion) in the process. (Bloomberg) The companies that have submitted the proposal include:
2. Toshiba’s group, which includes Babcock & Wilcox Co. (BWC) and Shaw Group Inc. (SHAW)
3. Areva, the world’s biggest maker of nuclear reactors.
----(Bloomberg)
References:
Borneo Post, 13/4/2011.
No comments:
Post a Comment