東日本大震災の地震、津波は福島原発の爆発事故、放射線汚染の恐れを引き起こしました。 日本はどうして核災害の可能性に直面しているのでしょう？ 原爆被害国の日本であり、日本は地震がどこにでもある国なのになぜ原発を続けるのでしょう？ オーストラリアは地盤がしっかりしていて、地震もほとんどない国ですが、原発はありません。 しかし、オーストラリアは原子力発電に必要な資源、ウランの最大輸出国です。原発がなくなると困る国です。
As if the disaster in Japan wasn’t bad enough already then came news of another threat. The combined force of both the earthquake and tsunami knocked out power to one of the country’s nuclear power stations leading to explosions and fears of radiation leaks. So why is Japan facing a possible nuclear disaster? Let’s take a look.
NATHAN BAZLEY, REPORTER: In the aftermath of the Japanese quake disaster, these explosions created shockwaves that moved through Japan and the world. Survivors that already made it through so much, now had a new and invisible threat to contend with radiation.
WOMAN (translated): As for radiation, I’ve heard it can come down from the sky with the rain.
EVACUEE (translated): Nuclear power is the most frightening thing, even more than the tsunami.
But is Japan really on the brink of nuclear disaster? To work that out, we need to look at how nuclear power stations work and how this one stopped working.
Most nuclear plants run on a fuel called uranium. Once they put it in a reactor and treat it a certain way, uranium releases huge amounts of radiation. This incredible heat energy is controlled and used to boil water to make steam, which then drives a turbine to generate electricity.
A lot of effort goes into making sure the heat from the nuclear reaction doesn’t get out of control. So water cooling systems work continuously to keep the temperature at safe levels.
But in Japan, the quake and tsunami knocked out many of the safe-guards meant to protect the reactors. The absolute worst case scenario in nuclear situations is a nuclear meltdown. That’s when the fuel rods heat up so much they start to melt. From there they can explode and blow deadly radiation into the air.
In the 80’s in a place called Chernobyl, this actually happened. An explosion blew huge amounts of radiation into the sky. Thousands were killed over time and it made a big area uninhabitable.
So far in Japan, there hasn’t been a nuclear explosion. Those big explosions were a result of gas blowing up in the sheds that house the nuclear reactors. But there have been radiation leaks, and that’s been enough to worry the authorities.
People have been evacuated from nearby towns. And many have been tested for radiation with these special scanners. High levels of radiation can lead to cancer.
The radioactivity at the nuclear plant has reached high levels around the same amount as getting thousands of x-rays per hour, which is dangerous. But in the communities surrounding, only small levels have been detected. Much less than even one x-ray in most areas.
This nuclear emergency has led other earthquake prone countries to question the safety of their nuclear power plants. In Australia, where we don’t have any nuclear power, some are saying this is a perfect example of why we shouldn’t ever consider it.
But others say a similar quake disaster here is extremely unlikely. Also, they point to the fact that the Japanese plant is around 40 years old, and the modern day nuclear plants are much safer.
All of these debates will continue on in the background, but everyone’s immediate concern is for the people of Japan, as they face the latest equally scary threat. And unlike the effects of the first natural disasters, the full effects of a nuclear disaster may not be known for years to come.
1. What issues were raised in the Nuclear power story? 2. Describe the events leading up to the nuclear power station crisis in Japan. 3. What fuel do most nuclear plants run on? 4. How is radiation turned into electricity? 5. Why are cooling systems important? 6. What is a nuclear meltdown? 7. What happened at Chernobyl in the 1980’s? 8. What health problems can high levels of radiation cause? 9. Do you think that nuclear power plants should be built in earthquake prone countries? Why or why not? 10. What do you understand more clearly since watching the BtN story?