accident at the "Fukushima-1" was caused by the earthquake and ensuing tsunami.By itself, the station had a reserve of strength and stood to one of the natural action.
led to the catastrophe that hit directly at the plant by two natural disasters.The earthquake has turned off power supply stations, immediately after this, turn on emergency generators, but they are also a long time worked by the tsunami.
causes of the accident "Fukushima-1" was built in the 70s of the last century and at the time of the accident simply obsolete.Project nuclear power plant did not expect the availability of funds accident management, which would be outside the project.
And if the station has withstood the earthquake, the tsunami, as mentioned above, the NPP left without electricity.
Before the accident worked three units and they were left without cooling, as a consequence - the fluid level has declined, but the pressure that began to create steam, it was, on the contrary, increase.
development disaster began with the first unit.To the reactor was not damaged due to high pressure steam decided to throw in the germooblochku.But it is also rapidly increased pressure.
Now to save it began to steam discharged directly into the atmosphere.Managed to maintain containment, but hydrogen, which is formed due to denudation of fuel leaked obstroyku reactor compartment.
All this has led to an explosion of the first power unit.It happened the day after the earthquake on March 12th.The explosion partially destroyed the concrete structure, but the reactor vessel was not damaged.
Developments
After the explosion at Unit greatly increased levels of radiation, but a few hours later dropped.On the territory of the plant "Fukushima-1" samples were taken, and studies have shown the presence of cesium.This meant that the tightness of the reactor is broken.
to cool the reactor began to pump sea water.The next day, it turned out that in the third block of the emergency cooling system is damaged.And there was a suspicion that the fuel rods partially exposed, and again a hydrogen explosion could occur.
began to drop pairs of containment and pumping seawater.But it did not help, and the explosion took place March 14th.However, the reactor vessel was not injured.
will continue to work to restore electricity to the first and second blocks.Also continued to pump water on the first and third blocks.
the same day denied the emergency cooling system and to the second power.Began pumping sea water for cooling.But suddenly broken valve to release steam and pumped water was impossible.
But the trouble, "Fukushima-1" is not over.An explosion at a second power still had a morning of March 15.Immediately exploded nuclear fuel storage facility at the fourth power.The fire was put out only two hours.
March 17 in the morning began to drop sea water from helicopters into the pools of Units 3 and 4. After the diesel stations was restored in the sixth block, it became possible to pump water using pumps.
eliminate accidents
to staff the system became operational, it took to restore electricity.And for his recovery had to pump out water from the flooded turbine units.
all complicated by the fact that the radiation level in the water was very high.The question arose: where to pump out the water.To this end, we decided to build a sewage treatment plant.
Company, which owns the "Fukushima-1", said that she would have to lose 10 tons of water with low radiation into the sea to make containers for highly radioactive water from the first three blocks of the plant.
Under the plan, the complete elimination of the consequences will take about forty years.Nuclear reactors were stopped, and began removing spent nuclear fuel from the pools.Later it expected to complete the dismantling of nuclear reactors, "Fukushima-1".
consequences of the accident
As a result, all the events occurred radiation leak.The Government had to evacuate people from the 20-kilometer zone around the plant.It is strongly recommended to evacuate those who lived 30 kilometers from the nuclear power plant "Fukushima-1".
Japan, "Fukushima-1" and its surroundings contaminated with radioactive elements.They are also found in drinking water, milk and other products.The rate was below the permissible, but for reassurance their use temporarily banned.
Revealed radiation in sea water and soil.In some regions of the world increased radiation background.
Besides environmental pollution, there are financial losses.Tersa Company is obliged to pay compensation to the victims in the accident.
«Fukushima-1" today
Today at the plant continues liquidating work.In May 2015 there was a leak of radioactive water.Also continuing purification of water removed from the blocks.
This is one of the main problems.Highly radioactive water very much, and in the process of cooling the reactors it is even more.It is pumped into special underground storage, gradually clearing.
