Treated water containing radioactive substances such as tritium, which continues to increase more than 10 years after the accident at TEPCO's Fukushima Daiichi Nuclear Power Station.
Regarding the disposal method, the government has decided to dilute the concentration below the national standard and then release it into the sea.
The government decided the policy after more than seven years of consideration, but there was deep-rooted opposition to the release to the ocean, especially in the local area, and experts pointed out that it left a problem in the understanding and conviction of the people concerned such as the local area. I will.
We have summarized the process so far, the specific method of ocean release, and the policy of measures against reputational damage.
Last year, at a meeting held by the government, six out of 43 people from 29 groups, including local residents and fishermen, and individuals expressed their clear opposition to the release into the sea, and the municipal council in Fukushima Prefecture. Then, a series of opinions were passed calling for opposition to the ocean release and a cautious response.
In addition, Hiroshi Kishi, chairman of the National Federation of Fisheries Cooperatives, who met with Prime Minister Suga on the 7th of this month, emphasized that "the idea that the release to the ocean is absolutely against" does not change at all.
“There are few opportunities for two-way dialogue between the country and the local community” <Expert>
Why did this happen?
Experts have pointed out that the fact that there were few opportunities for two-way dialogue with stakeholders, including the local community, had an effect.
Since 2013, the national government has set up a committee of experts to study the disposal method, and last year, the national subcommittee diluted it below the standard and said, "It is realistic to release it into the sea or the atmosphere." I have compiled a report to do.
During this time, in 2018, a "public hearing" was held in which the general public, including local residents, expressed their opinions, and written opinions were solicited. I didn't get it.
Last year, the government held a meeting to hear opinions from local agriculture, forestry and fisheries workers and commercial and industrial organizations nationwide to decide the disposal policy, but most of the attendees were within the time allotted by the representatives of the organization. It was not a two-way dialogue because it was a form of opinion.
A written solicitation was also made, but the government did not provide any views on these opinions before the policy was decided.
The Ministry of Economy, Trade and Industry has adopted this format in order to hear as many opinions as possible, and said that there was no material for exchanging opinions during the examination when the direction of disposal was undecided.
"Issues for Residents to Participate in Discussions" <NHK Questionnaire>
In February, NHK conducted an Internet survey of 1,200 people in Fukushima Prefecture and asked about the disposal of treated water containing tritium.
When asked
"Is the
local residents and other related parties fully participating in the discussion?"
▽ "I agree" was 3%
▽ "If anything, I agree" was 10.4%
▽ "I don't think so" 37.4%
▽ "I don't think so" was 23.8%,
indicating that how the residents participated in the discussion was an issue.
Experts “Efforts to be understood by government officials are necessary in the long term”
Professor Kota Juraku of Tokyo Denki University, who is familiar with the relationship between nuclear power and society, said that the government decided the policy while there were voices of opposition from people involved in the fishing industry. I think this is a lot of recognition, but the parties may not have the response that their opinions are concretely reflected in the policy. There is a place for the parties concerned to seek solutions while interacting with each other. It is regrettable that it was not provided sufficiently. "
On top of that, the government said that it would take a long time to make efforts to gain the understanding of the people concerned in order to actually release it. If it is decided by responsibility, it is necessary to properly verify the past history and build a relationship of trust again. "
In the first place, what is tritium?
Tritium is a radioactive substance called "tritium" in Japanese and is a member of hydrogen.
Since it is also generated in nature by cosmic rays flying from space, it is contained in water vapor, rainwater, seawater, and tap water in the atmosphere, and a small amount of tritium is also present in our bodies.
Tritium is also generated in ordinary nuclear facilities, diluted according to the standards of each country, and released into the sea and the atmosphere.
Since it is a member of hydrogen and exists as a part of water, it is difficult to separate it from water and remove it, and it can be removed even by using a device that removes many radioactive substances from the contaminated water of Fukushima Daiichi Nuclear Power Plant. you can not.
At nuclear power plants in Japan, we release it to the sea after confirming that it is below the standard of 60,000 becquerels per liter, and we also set the standard in each country and release it overseas.
The radiation emitted by tritium has low energy and travels only about 5 mm in the air.
For this reason, it is said that the risk of the effects on the human body when taken into the body should be considered rather than those from the outside.
The national subcommittee has
pointed out that some tritium may bind to organic substances such as proteins and concentrate in the body.The body has a function to repair DNA, and animal experiments and epidemiology The study concludes that the fact that tritium has greater health effects than other radioactive substances was not found.
In addition, in
the carcinogenesis experiment of mice, no example of the effect that tritium seems to be the cause has been found around the nuclear power plant, which is about the same as the frequency of occurrence in the natural world.
Professor Hiroshi Tauchi of Ibaraki University, who is familiar with the properties of radioactive substances and served as a member of the national subcommittee, points out that the level of concentration is important when considering the effects on the human body.
On top of that, Professor Tauchi said, "Although there is certainly a mechanism by which tritium is taken into the body and damages DNA, DNA has a function to repair it, and it is common for cells to be damaged and repaired by ultraviolet rays or stress. We are looking at the effects on cells, but no effects on cells have been confirmed so far at low concentrations below the standard, "he said, and the risk is low if the low concentrations can be managed appropriately.
How is the ocean release done?
Treated water containing tritium, etc. stored in tanks at the Fukushima Daiichi Nuclear Power Plant should be released into the sea as it is because the concentration of tritium currently exceeds the national standard when it is released into the environment. can not.
In addition, some radioactive substances other than tritium have concentrations exceeding the standard.
Therefore, for release to the ocean, the radioactive substances are first removed through a dedicated purification facility until the concentration of radioactive substances other than tritium falls below the standard, and the concentration is reduced.
On top of that, tritium, which cannot be removed by these facilities, is diluted with seawater and released at a level well below the standard.
The government will strengthen monitoring before and after the release, start with a small amount of release while checking the impact on the environment, and stop the release if an abnormal value is obtained in the monitoring. ..
It is necessary to create a new facility to dilute the concentration of tritium and release it, and TEPCO will consider a concrete plan for design and release in the future and will be examined by the Nuclear Regulation Authority.
Country TEPCO, has asked that the prospect of the two years later promote a specific preparation, such as the installation of equipment to be able to start the sea discharge.
What is the standard?
The national standard for releasing tritium into the environment is 60,000 becquerels per liter or less.
The government says that the concentration of treated water containing tritium and other substances when it is released into the sea will be reduced to less than 1500 becquerels per liter, which is 1/40 of the standard.
At the Fukushima Daiichi Nuclear Power Plant, groundwater is pumped up around the building and discharged into the sea in order to control the amount of contaminated water generated, but this also contains tritium.
TEPCO's voluntary standard for releasing such water into the sea is less than 1500 becquerels per liter, and the national government says that it will be the same level for the release of treated water containing tritium into the ocean.
In addition, the amount of tritium released in one year will be below the level of 22 trillion becquerels, which was the standard when the Fukushima Daiichi nuclear power plant was operating normally before the accident. It will be reviewed regularly.
Tritium emission <Domestic nuclear power plants>
Tritium is also generated during normal operation of nuclear facilities, and is diluted according to the standards of each country and released into the sea and the atmosphere.
At domestic nuclear power plants, it is released into the sea after confirming that it is below the standard of 60,000 becquerels per liter.
This is the amount of tritium released from nuclear power plants in Japan for one year (FY2019).
▽ Kansai Electric Power
Ohi Nuclear Power Station 56 trillion Bekrel
Takahama Nuclear Power Station 13 trillion Bekrel
Mihama Nuclear Power Station 860 billion Bekrel
▽ Kyushu Electric Power
Genkai Nuclear Power Station 50 trillion Bekrel
Kawauchi Nuclear Power Station 55 trillion Bekrel
▽ Shikoku Electric Power
Ikata It is 16 trillion becquerels at nuclear power plants
.
According to a summary by the Ministry of Economy, Trade and Industry, the average annual release amount for the five years before the Fukushima Daiichi accident is 18 to 87 trillion becrel for a type of nuclear power plant called pressurized water reactor, which is the same boiling water as the Fukushima Daiichi nuclear power plant. It is a type of nuclear power plant called a type, which has a value of 0.02 trillion to 2 trillion bekrel.
At TEPCO's Fukushima Daiichi Nuclear Power Station, more than 2 trillion becquerels were released in 2010, before the accident.
Tritium emission <Nuclear power plants abroad>
Tritium is generated when operating nuclear facilities overseas, and is released into the ocean and the atmosphere based on the standards set by each country.
There are differences in the amount of emissions depending on the type of nuclear power plant and the type of facility, and according to the summary of the Ministry of Economy, Trade and Industry, in 2002,
42 trillion becquerels at the Daiawan nuclear power plant in China
▽ American caraway The nuclear power plant also releases 42 trillion becquerels.
In addition
, 241 trillion becquerels as liquid and 254 trillion becquerels as gas were released at
the Darlington nuclear power plant in Canada in 2015
.
▽ In addition, the Chernavoda nuclear power plant in Romania released
85 trillion becquerels
in
liquid and 286 trillion becquerels in gas in
2002.
▽ The Walson (Tsukishiro) nuclear power plant in South Korea
released 17 trillion becquerels
in
liquid and 119 trillion becquerels in gas in
2016
.
The more the amount of release in the reprocessing facility
▽ French La Hague reprocessing facilities in 2015
trillion 1 Kyocera 3700 in a liquid becquerels, gas at 78 trillion becquerels
in the same 2015 in ▽ British Sellafield reprocessing facility
in liquid 1540 trillion becquerels and 84 trillion becquerels are released as gas.
To TEPCO's facility capacity examination Nuclear Regulatory Commission
The Nuclear Regulatory Commission is expected to examine the capacity of the equipment for diluting tritium applied by TEPCO in the future, and if it does not pass this, the equipment will not be allowed to operate.
In order to release the treated water accumulated in the tank, it is necessary to create a dedicated facility to dilute tritium to a concentration below the national standard, and TEPCO will add to the decommissioning plan of the Fukushima Daiichi nuclear power plant in the future. We will also reflect the equipment to be made and apply for examination to the regulatory committee.
Upon receiving an application from TEPCO, the Regulatory Commission will check during the examination whether the ability to dilute tritium to a concentration below the standard is secured and the soundness of the equipment.
In addition to the examination, there are also procedures such as inspections that are carried out after the construction work, and Chairman Sarada of the Regulatory Commission has indicated that it will take about two years for the necessary period for these examinations and inspections. If you do not pass, the equipment will not be allowed to operate.
In addition, the Regulatory Commission is considering strengthening the measurement of radioactive substances contained in seawater in the sea area around the Fukushima Daiichi Nuclear Power Plant after the implementation of the ocean release, and will confirm whether there is a significant change in water quality. ..
Rumor measures The discussion did not deepen ...
On the other hand, it has been pointed out that the debate did not deepen even though it took more than seven years for the government to decide on the policy.
At the meetings to hear opinions from local agriculture, forestry and fisheries industry and business and industry groups nationwide, which were held seven times from April last year, more than half of the 43 people from 29 groups requested that they show measures against reputational damage. ..
Originally, the government stated that it would discuss social impacts such as reputational damage caused by the disposal of treated water containing tritium in the national subcommittee from 2016.
However, in the report, the case of the ocean release, while there has been pointed out that the social impact is particularly large, is indicated measures
▽ monitoring of the surrounding environment enhancements and
▽ polite information transmission of measurement results and scientific knowledge
it
▽
There were a number of voices saying that the local government could not see any concrete measures
, only expanding and strengthening the existing measures that Fukushima Prefecture and others had been working on
.
The Ministry of Economy, Trade and Industry says that it was difficult to proceed with a diligent discussion on measures against rumors, even if it was a tentative story, while the disposal method was not decided as to the reason.
Professor Ryota Koyama of Fukushima University, who served as a member of the national subcommittee, said, "Before deciding the method, it was possible to simulate in advance what kind of impact and damage there would be in the case of ocean release, but to think about countermeasures. Perhaps the government was concerned that it seemed that the method had been decided at that time. Normally, it would be easier to reach consensus if the magnitude of the impact, the content of the measures, and the sense of scale were discussed in advance. I think it was. "
Regarding future rumors measures, "We should analyze the current situation once to see what measures were effective based on the characteristics of industries such as fisheries and tourism, rather than just expanding the rumors measures so far. Since the fishing industry is not in full operation and is still vulnerable as a management body, it is necessary to support not only measures for distribution and consumption but also a production base that strengthens the management body. "
The government is "perfect for rumors"
When releasing treated water containing radioactive substances such as tritium into the sea, the government has decided to take all possible measures against reputational damage.
Specifically, in order to minimize the influence of rumors, the concentration of tritium is diluted to 1/40 of the national standard and 1/7 of the drinking water standard set by the WHO = World Health Organization before being released into the sea. And then.
In addition, agriculture, forestry and fisheries industry and local government officials will join in to strengthen monitoring to monitor concentrations before and after the release, and with the cooperation of the IAEA = International Atomic Energy Agency, ocean release will be carried out in line with international practice. We will disseminate information such as what is being said based on scientific grounds.
Furthermore, in order to increase the landing, we will continue the support project for the introduction of equipment for fishermen, and also support the brokerage of local and surrounding local governments and the development of sales channels for processors.
In addition, the tourism industry is also concerned about damage to rumors, and it is said that it will take measures for full-scale reconstruction, such as attracting tourists and promoting sales of local products.
TEPCO is requesting compensation for the damage caused by rumors even if these measures are taken.
Then, a new meeting will be set up by the relevant ministers to flexibly implement additional measures as needed.
Expert "Scientific understanding and maintenance of distribution channels"
Associate Professor Yasumasa Igarashi of the University of Tsukuba, who is familiar with rumors, said, "It is very important to foster a scientific understanding of the safety of treated water, but the structural rumors are structural. The problem is that at each stage of distribution, there is a situation in which the demand itself declines due to excessive science that customers may care about, and it becomes impossible to buy before consumers understand it. "
On top of that, "It is important to foster scientific understanding and to show measures to never lose or expand the distribution channels of seafood in Fukushima Prefecture and the surrounding area, like the two wheels of a car. It is important to continue to create a situation where it is okay because it is done. "In addition to fostering scientific understanding, the need for measures at each stage of production, processing, distribution, and consumption was included. It is said that it can be evaluated.
On the other hand, regarding compensation in the event of rumors damage, "It is natural to compensate in the event of rumors damage as a major premise, but whether the successor generation can find the future in the fishery that continues compensation and children I'm worried that I'm going to pass it on to my grandchildren, and the longer the compensation, the harder it will be to find a future outlook for this industry. I think that the vision of how to create an area centered on the fishing industry should be clarified through dialogue with the parties concerned. "
Expert "If nothing is done, rumors cannot be avoided, and measures should be taken."
Associate Professor Naoya Sekiya of the University of Tokyo, who served as a member of the national subcommittee, said about the government's policy decision this time, "How much the people understand and disseminate about treated water remains insufficient. I think that the current situation is that it has reached the present. If it is released as it is, it is inevitable that reputational damage will occur, and we have to think concretely what we will do to gain the understanding of the people in the two years until the release. I have to. "
More recently, he mentioned that TEPCO's misconduct has been occurring one after another. "10 years after the accident at the Fukushima Daiichi Nuclear Power Station, various problems have arisen and I am feeling relaxed. I think the issue is how to ensure the reliability of the disposal by TEPCO, not the stage where it can be trusted, "he said, pointing out the importance of gaining the understanding and trust of the people.
He also pointed out that it has become a political issue internationally. "For the past few years, scientific issues have been left untouched as political issues in China, South Korea, Taiwan, etc. There are also situations where it is being reimported, "he said, calling for the need to disseminate information to neighboring countries.