The main load from nuclear waste after the disaster at the Fukushima-1 nuclear power plant was felt by the ocean, and only then by the atmosphere. This was announced on July 8 by the co-chairman environmental group "Ecological protection!" Vladimir Slivyak, answering a reporter’s question about the consequences of the release of radiation in Japan and current situation with the atmosphere and bodies of water.
“The bulk of the radiation from Fukushima still ended up in the ocean. Compared to what still ends up in the ocean, less has ended up in the atmosphere. But it still needs to be said that after Fukushima there was no large radioactive cloud, like after Chernobyl, that would fall in large parts on large areas. Some amount of radionuclides entered the atmosphere, but I have not seen specific estimates of the amount of releases. However, if they entered the atmosphere, they would end up somewhere on Earth. Where exactly is unknown. We can only say that there is really a small concentrate there, and there was one over Moscow too, but very small.
If we also talk about small concentrations, then the radiation from Fukushima flew over everything Northern Hemisphere. How and where it fell - there is no such data, and I, frankly, cannot imagine when such data might appear, and this is probably a matter of some careful and rather lengthy research. Will they be made in different countries— I’m not sure, because they may think that the concerts were small and no one would drop dead. Main place in terms of radioactive emissions“It’s still an ocean,” the ecologist explained.
The specialist also warned about the dangerous ecological situation, which is already taking shape in the Far East: “If we are talking about Russia, then this Far East, and, of course, if it’s completely reasonable, then we need to very strictly monitor what is caught from the Far East, but, again, it’s difficult for me to say how carefully Russian authorities will keep an eye on this because there is real threat ban on fishing, because controlling the catch of clean and radioactive fish is quite difficult and expensive. And there is a real chance that if you do all this honestly, many people will simply be left without work. With a high degree of probability, it is impossible to obtain seaweed and seafood in general at a fairly large distance from Fukushima in the Far East. I have seen studies that confirmed that Fukushima radiation in small quantities is harmful at a distance of 400 km in the ocean. We must not forget that a considerable amount of radioactive fish swims in the ocean, and, of course, some of it swims to other seas and oceans, and it is almost impossible to control all of this. By the end of this year, it will be possible to catch fish in any ocean in which radiation from Fukushima can be found. And with this, unfortunately, it is difficult to understand what can be done, because it is difficult to establish such control throughout the world to check every fish, and no one will do this - it is too difficult and expensive.”
Let us recall that in the spring, many experts stated that a radioactive cloud coming from Japan spread throughout Russia and even reached Moscow, without, however, citing any official sources. In addition, experts say that the main danger from the point of view of ecology and nuclear waste is seafood and fish, but they stipulate that visitors to city sushi bars have nothing to fear: all the fish in these establishments is brought mainly from Norway and Finland , and these supplies have nothing to do with Japan.
The accident at Fukushima-1 was caused by an earthquake and the subsequent tsunami. The station itself had a safety margin and would have withstood one of the natural disasters.
What led to the disaster was that two nuclear power plants were hit at once. Because of the earthquake, the power supply to the station was turned off, immediately after that the emergency generators turned on, but they also did not work for a long time due to the tsunami.
Causes of the accident
The Fukushima-1 nuclear power plant was built in the 70s of the last century and at the time of the accident was simply obsolete. The design did not assume the presence of accident management facilities that would be outside the scope of the design.
And if the station withstood the earthquake, then the tsunami, as mentioned above, left the nuclear power plant without power supply.
Before the accident, three power units were operating, and they were left without cooling; as a result, the coolant level decreased, but the pressure that the steam began to create, on the contrary, began to increase.
The development of the disaster began with the first power unit. To prevent the reactor from being damaged due to high pressure, they decided to dump the steam into the containment. But the pressure in her also quickly increased.
Now, to preserve it, they began to dump steam directly into the atmosphere. The containment was preserved, but the hydrogen, which was formed due to the exposure of the fuel, leaked into the reactor compartment.
All this led to an explosion at the first power unit. It occurred the day after the earthquake. The explosion partially destroyed the concrete structures, but the reactor vessel was not damaged.
Developments
After the explosion, the radiation level at the power unit increased greatly, but dropped a few hours later. Samples were taken on the territory of the Fukushima-1 nuclear power plant, and studies showed the presence of cesium. This meant that the reactor's seal was broken.
Sea water was pumped in to cool the reactor. The next day it turned out that the emergency cooling system in the third unit was damaged. And a suspicion arose that the fuel elements were partially exposed, and a hydrogen explosion could occur again.
They began to release steam from the containment and pump in sea water. But this did not help, and on March 14th. However, the reactor vessel was not damaged.
Continue work to restore electricity to the first and second units. They also continued pumping water to the first and third blocks.
On the same day, the emergency cooling system at the second power unit also failed. They started pumping in seawater for cooling. But suddenly the steam release valve broke, and it became impossible to pump water.
But the troubles of Fukushima-1 did not end there. The explosion at the second power unit nevertheless happened on the morning of March 15. The vault immediately exploded nuclear fuel at the fourth power unit. The fire was extinguished only after two hours.
On the morning of March 17, sea water began to be dropped from helicopters into the pools of blocks 3 and 4. After the diesel station on the sixth block was restored, it became possible to pump water using pumps.
Elimination of the accident
In order for the standard systems to begin functioning, it was necessary to restore the power supply. And to restore it, it was necessary to pump out water from the flooded turbine compartments.
Everything was complicated by the fact that the level of radiation in the water was very high. The question arose: where to pump this water. For this purpose, they decided to build a wastewater treatment plant.
The company that owns Fukushima 1 said it would have to dump 10,000 tons of low-radiation water into the sea to free up highly radioactive water tanks from the plant's first three units.
According to plan, complete liquidation the consequences will take about forty years. The nuclear power plant's reactors were shut down and the removal of waste from the pools began. Later, it is planned to completely dismantle the reactors of the Fukushima-1 nuclear power plant.
Consequences of the accident
As a result of all events, a radiation leak occurred. The government had to evacuate the population from a 20-kilometer zone around the nuclear power plant. Those who lived 30 kilometers from the Fukushima-1 nuclear power plant were strongly recommended to evacuate.
Japan, Fukushima-1 and its surroundings are contaminated with radioactive elements. They were also found in drinking water, milk and some other products. The norm was below the permissible limit, but to be on the safe side, their use was temporarily banned.
Radiation was detected in sea water and soil. In some regions of the planet it has increased
Besides pollution environment, there are financial losses. The TERCO company is obliged to pay compensation to victims of the accident.
Fukushima-1 today
Today, liquidation work continues at the nuclear power plant. In May 2015, radioactive water leaked. The purification of water extracted from the blocks also continues.
This is one of the main problems. There is a lot of highly radioactive water, and as the reactors cool, it becomes even more abundant. It is pumped into special underground storage facilities, gradually purified.
After the radiation release in Japan, Tokyo residents are buying dosimeters en masse. Russian students in the capital of Japan they say that many foreign students are trying to return to their homeland or move further from the Fukushima-1 nuclear power plant - to the south of the country. The German airline Lufthansa has transferred its flights from Tokyo to southern cities Nagoya and Osaka.
However, so far both officials and experts say that there is no reason to panic: radiation threatens only the station’s workers.
Japanese Prime Minister Naoto Kan stated that employees were sacrificing their lives trying to cool the reactor. It was reported the day before that at some points of the station, in particular near the third reactor, radioactive radiation amounted to 400 millisieverts or 40 roentgens per hour (the country's authorities later reported a decrease in radiation levels). When exposed to 200-400 millisieverts of radiation in a person, the number of blood cells may decrease, and the likelihood of developing in the future increases. cancer diseases And genetic mutations. Deputy Director research institute reactors at Kyoto University, Professor Sentaro Takahashi, control specialist radiation safety told NHK that for workers of Japanese nuclear power plants permissible level radiation exposure is up to 50 millisieverts per year.
As the head of the energy department of Greenpeace Russia (Greenpeace closely monitors the radiation situation in Japan and publishes reports on its website every two hours), Vladimir Chuprov, explained to Gazeta.Ru, during the accident at Chernobyl nuclear power plant workers were suspended from work when they received a radiation dose of 25 roentgens. “That is, in fact, now the workers of the Japanese nuclear power plant are really sacrificing their health, receiving an annual dose of radiation in an hour. There is unverified information that they are replaced literally every 15 minutes, but there is no official confirmation of this information,” says the ecologist.
At the same time, environmentalists note that in fact, under current conditions, radiation danger threatens only residents located within a radius of approximately 20 kilometers from the nuclear power plant.
According to Greenpeace program director Ivan Blokov, on Tuesday afternoon at the border of the nuclear power plant, the radiation amounted to 1 millisievert per hour. However, he noted that millisievert radiation is “the norm for an ordinary citizen who does not work with nuclear materials.” “That is, being in this territory, you can receive an annual dose of radiation in an hour. For comparison, when receiving radiation of, for example, 6 thousand millisieverts, 70% of people die. That is, if the radiation level continued to remain at this level for a long time, then this portion could be obtained in 6 thousand hours, that is, 250 days.”
At the same time, environmentalists emphasize that the level of radiation is changing all the time, as is the situation at nuclear power plants.
“The increase in radiation levels may be temporary. For example, if it was called by a thread inert gas, then the gas may soon dissipate, and the radiation level will drop,” says, in particular, Takahashi.
In general, exposure can be external or internal. Radioactive substances can enter the body through the intestines (with food and water), through the lungs (by breathing) and even through the skin (as in medical diagnostics radioisotopes). Significant impact on human body provides external irradiation. The extent of exposure depends on the type of radiation, time and frequency. The consequences of radiation, which can lead to fatal cases, occur both with a single stay at the strongest source of radiation, and with constant exposure to weakly radioactive objects.
In the provinces of Japan, the radiation level is at currently is low, and there are no serious consequences for the health of residents.
Blokov notes that an “unpleasant level of radiation” was recorded in residential sectors 70 kilometers from Fukushima-1: it amounted to 0.005 millisieverts per hour. “The background is 100 times higher than usual for this area. But it is not critical,” says the ecologist.
In Tokyo, the maximum radiation level on Tuesday afternoon was 0.00089 millisieverts per hour. In fact, with the detected level of radiation, a Tokyo resident could receive a radiation dose eight times higher than normal in a year. But only on the condition that this level of radiation will continue to exist.
Chuprov explains that when receiving a radiation dose of up to 100 millisieverts (meaning long span time - people can receive such a dose for days and years) so-called stochastic effects occur in the body - in fact, this is the probability of getting cancer or a genetic disorder, but only a probability. As the dose increases, it is not the severity of these effects that increases, but the risk of their occurrence. Further, we can talk about deterministic, inevitable harmful effects.
In the current situation, radiation does not pose a threat to Russian territories.
Director of the Institute of Problems safe development nuclear energy(IBRAE RAS) Leonid Bolshov told Gazeta.Ru that the Far East will not suffer “even with worst case scenario"He's too far away."
At the same time, experts unanimously say that it is now impossible to predict the consequences and threat of the accident at Fukushima-1 for the population: the level of radiation is constantly changing, although it can only be called critical within the walls of the plant itself. “There is not enough data to reach the level of reliability of the forecast,” says Bolshov.
Experts note that the situation at Fukushima-1 is non-standard. The accident occurred due to powerful natural disaster- earthquake, followed by aftershocks and tsunamis. "If there were problems nuclear power plant If there were only problems, then Japanese specialists would have dealt with it themselves,” says the director of the institute, whose specialists, together with Rosatom specialists, are in Japan. Fukushima-1, he said, was prepared for earthquakes, but the disaster exceeded even the maximum calculations. Due to the lack of detailed information about the state of the station, Bolshov says, it is impossible to make any accurate forecasts about how the situation will develop.
The Ramzaev St. Petersburg Research Institute of Radiation Hygiene is currently working on a forecast of the consequences for Russia after the accident at a nuclear power plant in Japan. “The information about the study is not entirely open yet, but we have already started. The document will be ready in the coming days,” the institute’s deputy director for scientific work Nadezhda Vishnyakova.
Even the always calm residents of the Japanese islands can't stand their nerves
In the Japanese prefecture of Fukushima, where it is located Japanese nuclear power plant Fukushima-1, radiation levels range from 30 to 1000 maximum permissible standards. The level of radiation fluctuations depends on the presence of water and dense vegetation in a particular place, which acts as a kind of filter and accumulates radiation.
The authorities are considering options for evacuating the population from those areas of the city where radiation exceeds permissible standards, Russia Today TV channel reports.
Meanwhile, the disaster
Fukushima-1 is beginning to move from an environmental and economic dimension into a psychological dimension.
The fear of widespread radiation, the uncertainty that the ground they walk on and the water they drink is not radioactive at levels several hundred times higher, is causing mass cases nervous breakdowns and even suicides.
Local media reports about a Japanese farmer who committed suicide due to the fact that he could not bear the weight of economic and personal problems after the accident at the Fukushima-1 nuclear power plant. A peasant who owned a dairy farm 40 kilometers from the nuclear power plant hanged himself in own home. He left inscriptions on the wall: “It’s all because of the nuclear power plant”, “For those who will live, do not give up in front of the nuclear power plant!”, RIA Novosti reports.
Economic consequences earthquakes, tsunamis and nuclear power plant accidents also went beyond direct destruction on March 11, 2011. Radioactive cesium was detected on tea plantations in Kanagawa and Shizuoka prefectures, its level exceeding the permissible level by 35%. In this regard, the volume of losses of tea producers is growing, and it is not clear when the impact of the radiation factor on this sector of the economy will stop. Many of those who were engaged in tea cultivation have already left this market.
Organs local government Japan was required to provide daily reports on the status of background radiation. Public Schools in Fukushima are equipped with dosimeters, teachers record their readings every hour, thereby creating a pollution map.
The most dangerous area in environmental terms is the northwest of Fukushima, where a lot of radioactive fallout fell in the form of snow and rain. There is no information about the state of the forced evacuation zone - 20 km from Fukushima-1. Environmentalists, in turn, insist on intensifying monitoring of land and water.
Absence reliable information about the real state of affairs led residents of the affected areas to “quiet despair.” “I don't want to hear anything about radiation anymore! I want to dig a hole in the ground and scream!” - said 63-year-old Shukuko Kuzumi, who lives in Iwaki, the capital of Fukushima Prefecture.
Let us recall that on March 11, an earthquake with a magnitude of about 9 on the Richter scale occurred in Japan, which caused a tsunami wave, the height of which is estimated to be up to 10 meters. Causing numerous destructions, the wave hit the Fukushima-1 nuclear power plant, which caused a breakdown in the power supply in the cooling system power plant stations. This subsequently led to a meltdown of nuclear fuel, which burned through the station’s protective casing and entered the groundwater.
Before this, specialists from the nuclear power plant operator TEPCO (Tokyo Electric Power) began to fill the reactor with water, trying to cool it. This led to the fact that water, falling on the energy rods and adjacent installations heated by the nuclear decay reaction, not only evaporated, but immediately decomposed into hydrogen and oxygen, which formed an explosive mixture and exploded. This resulted in an even greater release of radioactive elements, and also arose the problem of disposing of radioactive water, which was initially simply poured into the ocean.
All residents were evacuated from a zone with a radius of 20 kilometers; it was recommended to also leave the territory within a radius of 30 kilometers.
The disaster at Fukushima-1 received the highest, 7th class of danger according to international classification. Previously, only one accident at a nuclear power plant had such an “assessment” - Chernobyl disaster in April 1986.
As is known, the largest technological disaster, accompanied by the release of a huge amount radioactive substances into the atmosphere and coastal waters, occurred on March 11, 2011 in Japan. The reason for it was the earthquake and subsequent tsunami, which led to destruction at the Fukushima nuclear power plant, incompatible with further operation. The station was officially closed in 2013.
Representatives of the Japanese side announced a period of 40 years. This is exactly how much, according to nuclear experts, it will take to bring this object into a stable state. But what about that? More than 6 years have passed since the disaster. The first data is emerging that will help assess environmental consequences this terrible event.
The level of radiation at nuclear power plants is still so high that not only people, but also robots cannot be there. Even considering highest level development of Japan in the field of robotics, it has not yet been possible to create a device that would work there for a long time. Due to colossal radiation, all robots fail after a few hours, without having time to get through the rubble to the desired area. That is, no large-scale work is being carried out to eliminate leaks of radioactive fuel at the station. In this regard, from the moment of the accident to the present day, Fukushima has been supplying about 300 tons of radioactive water to the world's oceans every day. This water contains radioactive iodine-131, which decays almost immediately, as well as cesium-137, which has a half-life of 30 years. At the same time, a nuclear fuel leak occurs, the true extent of which is unknown.
In the picture: map of currents in Pacific Ocean Of course, such colossal volumes of contaminated liquid are not capable of dissolving without a trace even in the most big ocean planets. Due to the circulation features water masses in the Pacific Ocean, sea currents include radioactive contamination from Fukushima towards the northeast, to the coasts of Alaska and California. As noted by specialists from the Pacific Fisheries Research Center, as of the beginning of 2016, background radiation in the Sea of Okhotsk and other Russian fishing zones is within normal limits. At the same time, the situation off the coast North America, where contaminated water enters along with the North Pacific Current, does not look so optimistic. Off the coast of Western Canada, experts record an increase in radiation levels by 300%, and therefore, there has been a 10% reduction in the local ichthyofauna, including the population of Pacific herring. There are also widespread deaths of fish and starfish. And the content of radioactive substances in samples of Oregon tuna increased 3 times. General level radiation in the Pacific Ocean today is 5-10 times higher than that at the time of testing atomic bombs USA.
Even this limited information is enough to make a disappointing conclusion: Fukushima has already surpassed Chernobyl accident, which was considered the worst in the history of the planet. Unfortunately, humanity with its level technical development on this moment is unable to prevent the consequences of such large-scale environmental disasters.