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The situation at nuclear facilities in Japan is deteriorating by the hour. Agency for Nuclear Safety of France on Tuesday night accident estimated at plant Fukushima-1 six out of seven possible levels of severity on the international scale INES, raising the danger level with a fourth, previously assigned to the accident, the Japanese authorities. Recall Chernobyl accident qualify for the seventh level. Fukushima, a Japanese nuclear power plant Dayishi second fire at the store spent fuel at the 4-th block, damaged the protective shell 2 and the third reactor, increasing background radiation.

TEPCO, the operating company's plant Fukushima Dayishi, on Tuesday evening has officially confirmed that the second power station accident "apparently" still occurred depressurization "domestic containment" - the main protective barrier reactor. On Wednesday morning, the same information received on the third reactor of the plant.

Late Tuesday night, Moscow time, there were also reports of a second fire on the fourth block, where a crisis is a pool of spent nuclear fuel.Elevated levels of radiation make it difficult to hire professionals.

Tuesday night the representatives of TEPCO also said about boiling water in a cooling pond for spent nuclear fuel (SNF) to the fourth power - an alarming sign that signals the release of highly radioactive particles as a result of denudation and destruction of spent fuel assemblies.

Recent developments in the fourth unit Fukushima-1, resulting from early morning explosion and fire in a spent fuel storage, messaging supported by the International Atomic Energy Agency (IAEA), arriving with a reference to statements by the authorities of Japan.

The explosion at the fourth power plant Fukushima-1, which occurred on Tuesday morning, was caused by the accumulation and release hydrogen, which in turn led to a fire in the storage of spent nuclear fuel, the company said TEPCO, according to Epoch Times.The morning explosion was already the fourth since Saturday in an emergency situation at the station began to deteriorate sharply.

On Wednesday morning local time, access to technical personnel in some sections of the station was severely hampered by high levels of radiation, according to The Financial Times.Professional temporarily evacuated from the station after the radiation levels exceeded all permissible values. Has information on the clouds of white steam above the roof of the third power, after which they noted a strong increase in background radiation.

Specific source of the burst of steam can not be determined, but experts on nuclear safety and the representatives of TEPCO said about a possible depressurization of reinforced concrete containment of the third reactor, according to The Financial Times.

At the station, was immediately registered a sharp increase in background radiation - up to 6400 mikrozivert per hour, which exceeds the rate of 10 thousandtimes. Within 20-30 minutes after the incident with the release of steam to the third power unit of the radiation level again dropped by two-thirds of the marked peak.

At this point, information on damage to the containment of the second reactor due to hydrogen explosion on Tuesday morning has been confirmed by the operating company.The likelihood of this scenario, the result of which could be the destruction of the reactor core, hung in the air for Tuesday, while the media waited for reports from TEPCO.

Inner containment of the reactor - the main protective barrier, the last line of defense, and its destruction means the impossibility in the case of melting of the core to prevent the massive output of radiation outside.

MSNBC, citing Japan's nuclear agency, said that the explosion on the second power unit on Tuesday could be damaged by pool-bubbler system location of the accident - a reservoir at the bottom of the containment containing cold water to condense the vapor formed during the operation of the emergency protection.Pool-bubbler is also used to deactivate radioactive steam.

According to Viktor Glinski, a former Nuclear Regulatory Commission U.S. confirmation of the information about damage basin-bubbler second reactor and the containment means a serious deterioration of an already critical situation at the station.

"If this is true, it is a direct way [to radiation] in the premises of the station where the personnel and the environment" - said Glinski.

At this point in the Fukushima-1 are about 50 employees.The night before, TEPCO evacuated from the station 740 persons not involved directly in an emergency. The Financial Times reports on new injuries among staff.

The newspaper quotes Elmer Lewis, a nuclear expert Chicago, Northwestern University: "They are in a difficult situation.There comes a time when radiation levels are so high that experts may be in separate rooms only for short periods of time. Be a need for experienced staff who will not refuse to enter there. This is a serious ethical problem for the leadership. "

According to news agency Kyodo, TEPCO concerned about the possibility of the accident in the most critical - a situation in which the melting of the reactor core, the destruction of the fuel rods and a large-scale release of radiation into the environment.It is this, the worst case scenario occurred at Chernobyl.

Estimated to TEPCO, appeared on Wednesday in the core of the first reactor has already been subjected to the destruction of up to 70% of nuclear fuel, the second reactor, the degree of destruction of fuel rods - 33%. Problems with cooling are also on the fifth and six power stations that were disabled at the time of natural disaster on Friday.

"If the information [about the containment of the second reactor] is reliable, it can talk about the most difficult turn in the situation since the emergence of problems at the station last Friday" - confirmed an expert on nuclear physics Bellona Nils Boehmer.- "This is the last barrier preventing release of radioactive material from the reactor core to the environment."

According to Boehmer, damage to the protective shell - even though already otgremevshie four hydrogen explosion and the problems with the cooling of the six reactors Fukushima-1, as well as a fire in the storage of spent fuel at the fourth unit, at least, remain confident that the radioactive material will not go beyond the core.Now there is no such certainty. "

"The situation is deteriorating, and the crisis will not end in sight" - added Boehmer.

Meanwhile, on Wednesday morning at the store spent nuclear fuel of the fourth power second fire occurred.Spent fuel storage, as well as the nuclear power plant reactors, is having problems with cooling. The water level in the cooling pond falls, exposing the rods of spent uranium fuel, which leads to a release of radioactive particles into the atmosphere.

As reported by CNN, the Agency for Nuclear Safety of France on Tuesday night estimated the accident at the NPP Fukushima-1 six out of seven possible levels of severity on the international scale INES, raising the danger level with a fourth, previously assigned to the accident, the Japanese authorities. According to this scale, nuclear and radiological accidents and incidents are classified according to severity, where the first level refers to the incidents leading to low risk to personnel and the public.

Sixth - the penultimate level of risk damage to the scale, impact on staff and the possible risks to the public and the environment. The seventh level of the IAEA classification was assigned only to the Chernobyl catastrophe in 1986 as a "serious accident", accompanied by the scalenym release of radioactive materials, radioactive contamination of the environment and have significant implications for public health.

"Obviously, we are now witnessing the accident the sixth level, that is, somewhere between what happened at Three Mile Island and Chernobyl catastrophe" - the head of the French Minister Andre-Claude Lacoste, according to CNN.

Japanese authorities, as well as the IAEA, have so far refrained from new assessments of what is happening on the classification of INES.

But on Tuesday officials in Japan first began to speak openly about the possible dangers of radiation emissions from the emergency stations for population.

Speaking at a press conference Tuesday, Prime Minister of Japan, Naoto Kan urged people not to panic despite the "growing danger of radiation emissions from the station."

As RIA Novosti reported with reference to Reuters, the radiation level in the plant and the surrounding area after the explosion on Tuesday increased four-fold.At 08.31 am local time (03.021 MSK), the figure was 8.22 mikrozivert thousands per hour, and only 40 minutes earlier - 1,94 thousands mikrozivert.

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