Posted on 2020年5月15日 by aoki
ちくりん舎ではリネン吸着法という方法を用いて空気中のホコリのセシウム濃度を調査しています。
最近では宮城県大崎市の一般ごみ焼却炉での放射能ごみ焼却に合わせて、周辺での空気中のほこりのセシウム濃度を測っています。これらの資料は地元住民の皆さんの焼却中止を求める裁判においても証拠資料として提出しています。
これらのリネンに付着したセシウムは大部分が水に溶けない、不溶解性の粒子であることが今回分かりました。微小粒子は肺の奥まで入り込むことが知られています。そしてこれらが不溶解性であるということは、いったんこれらの粒子を吸い込むと肺に長く留まり長期的な内部被ばくにつながります。あらためて放射能ごみ焼却の恐ろしさが再認識できます。
今回のテストは大崎市の焼却炉周辺でのリネン吸着法調査で使用したリネン布、また比較のために、南相馬市でエアダストサンプラーを用いて調査を行ったときのフィルタについても同様のテストを行いました。
報告書はこちらからダウンロードできます。
2020_0515リネンに吸着したセシウム溶解性調査結果.docx
Fukushima Prefecture has been struggling with the spread of the new coronavirus, having identified in April at least four cases of clusters with five or more infected people in one place, with locations ranging from a post office to a welfare facility.
Ten people who have worked as postal staff including one retiree tested positive at the post office in Nihonmatsu. According to the prefecture, a postal delivery worker in his 40s was the latest person to test positive. He had a fever on April 3 but went to work the following day. Then, on April 6, he experienced a loss of taste and smell, but again reported to work.
[…]
In light of the outbreak, Nihonmatsu Mayor Keiichi Miho urged the prefecture to conduct coronavirus testing on all officials at the post office, but was told that would only be done if they showed symptoms.
The second cluster of infections was found at a factory in the city of Iwaki, while the third cluster occurred at Epoka, a health welfare facility in Motomiya city, with the virus suspected to have spread from people at the Nihonmatsu post office.
A woman in her 60s working at the facility tested positive on April 20. Her husband is a junior high school teacher in the city of Tamura, making him the first public school teacher in the prefecture to have become infected. He developed a fever on April 9 and has since stayed at home.
On April 25, the prefecture announced that a fourth cluster had developed at a sign manufacturing company in the city of Minamisoma. Male workers in their 60s and 20s tested positive after being in close contact with employees who had been infected earlier. Local health centers are looking into how they contracted the disease and their close contacts.
Read more.
By Kang Seung-woo
The Navy announced, Tuesday, plans to study the effects of radioactive water on its operations in an apparent countermeasure against Japan’s alleged plan to dump the contaminated water from its Fukushima nuclear plant into the ocean.
While many domestic and international environment groups have studied the possible water release by Japan, this is the first time that the Korean military has decided to investigate the issue, although it remains cautious about specifying Japan is the target country for the study.
According to a notice posted on the government’s procurement system site, the Navy plans to commission research into the potential impact of radioactive water within its operational areas on its maritime operations and ways to stably carry out missions.
The Navy said the 30 million-won ($24,000) research project is scheduled to run until Nov. 30.
“We recognize the growing possibility of radiation-contaminated water being released into our operational areas, and international environmental organizations have warned that if a neighboring country dumps radioactive water into the ocean, it would reach the East Sea within a year,” a Navy officer said.
[…]
Read more.
Jason K Ellis
OAK RIDGE, Tenn., May 11, 2020 — Researchers at the Department of Energy’s Oak Ridge National Laboratory are refining their design of a 3D-printed nuclear reactor core, scaling up the additive manufacturing process necessary to build it, and developing methods to confirm the consistency and reliability of its printed components.
The Transformational Challenge Reactor Demonstration Program’sunprecedented approach to nuclear energy leverages advances from ORNL in manufacturing, materials, nuclear science, nuclear engineering, high-performance computing, data analytics and related fields.
The lab aims to turn on the first-of-its-kind reactor by 2023. The program has maintained its aggressive timeline during the COVID-19 pandemic, using remote work to continue design and analysis efforts. [TCR video]
[…]
As part of deploying a 3D-printed nuclear reactor, the program will also create a digital platform that will help in handing off the technology to industry for rapid adoption of additively manufactured nuclear energy technology.
[…]
Through the TCR program, ORNL is seeking a solution to a troubling trend. Although nuclear power plants provide nearly 20 percent of U.S. electricity, more than half of U.S. reactors will be retired within 20 years, based on current license expiration dates.
[…]
The Transformational Challenge Reactor builds on ORNL’s 77-year history of international leadership in nuclear science and technology development. The lab began as home to the world’s first continuously operating reactor, and its scientists and engineers pioneered technology and expertise in the first decades of the Atomic Age.
Today, the lab operates the High Flux Isotope Reactor, a DOE Office of Science user facility that provides a world-leading source of neutrons for a variety of research and produces isotopes for medicine, industry, and space exploration. TCR will be the 14th reactor built and operated by ORNL.
Read more at 3D-printed nuclear reactor promises faster, more economical path to nuclear energy
By MUTSUMI MITOBE
Despite strong public opposition to the proposal, the Environment Ministry will soon start a trial demonstration to confirm the safety of growing food crops in soil decontaminated following the 2011 nuclear accident.
The ministry received nearly 3,000 public comments about its proposal to revise an ordinance to enable the soil to be reused across Japan, most of which opposed the proposal.
Many people are opposed to reusing the soil, saying, “It will spread contamination.”
At a news conference on May 1, Environment Minister Shinjiro Koizumi acknowledged, “I strongly recognize the fact that there are people who are opposing (the reuse of decontaminated soil). We will provide detailed explanations to seek understanding for our willingness to take a step forward even if it’s just a small one.”
The project, to start by the end of May at the earliest, will be conducted in the Nagadoro district in Iitate, Fukushima Prefecture. The district is designated as a “difficult-to-return” zone, where radiation levels remain high since the triple meltdown at the Fukushima No. 1 nuclear power plant following the Great East Japan Earthquake and tsunami.
The ministry is seeking to reuse decontaminated soil for public construction work and farmland development if the radiation level of the soil is below certain standards. In the last fiscal year, which ended in March, flowers and crops used to make solid fuel for biomass power generation were grown on land using the decontaminated soil.
[…]
In the Nagadoro district, there is a demonstration plot of farmland that spans about 600 square meters in total. The land comprises an 800-cubic-meter embankment of soil whose radiation level is 5,000 becquerels or lower per kilogram, and the embankment is covered with uncontaminated soil that is 50 centimeters thick.
Decontaminated soil is currently stored at interim storage facilities in Okuma and Futaba in Fukushima Prefecture. The law stipulates that the final disposal of the soil should be conducted outside the prefecture within 30 years from 2015, when the facilities began storing the soil.
The total amount of soil stored at such facilities is expected to reach about 14 million cubic meters, equivalent to 11 Tokyo Domes, located in Tokyo’s Bunkyo Ward.
Read more at Ministry to test growing veggies on cleansed soil in Fukushima
環境省は、東京電力福島第一原発事故にともなう除染で出た土を再利用した土地でトマトやキュウリなどを栽培して安全性を確かめる実証事業を今月中にも始める。帰還困難区域に指定されている福島県飯舘村長泥地区で行う。
環境省は、放射性物質の濃度が一定基準以下の除染土を公共工事や農地造成に再利用する方針を掲げる。長泥地区はそれに向けた実証事業の場所だ。昨年度は、造成した土地で花やバイオマス発電の固形燃料などになる作物を栽培。「十分安全側の結果が得られた」として、今年4月に除染土を全国で再利用できるよう省令改正をする予定だった。
しかし、地元から「食用作物も育てたい」との声があり、改正を先送りすることを決めた。食用作物は人が口にするため、安全性を改めて調べる必要があり、「実証事業」の中で新たに野菜を育てることにした。
除染土の再利用については「汚染の拡大になる」といった意見も強い。省令改正案のパブリックコメントには3千通近い意見が寄せられ、多くは反対だった。
小泉進次郎環境相は1日の会見で「反対の声があることもしっかり受け止める」とした上で「小さな一歩でも前に進めて行きたいということを、ご理解をいただけるよう丁寧に説明をしていきたい」と述べた。
[…]
除染で出た土は現在、中間貯蔵施設（福島県大熊・双葉両町）に運ばれているが、搬入が始まった2015年から30年以内に、県外で最終処分すると法律で定められている。貯蔵量は東京ドーム11個分の約1400万立方メートルに達する見込みだ。再利用は最終処分量を減らす目的で検討されている。（水戸部六美）
（略）
月城原発側などによると、今回の停止事故は励磁機の故障で発生した。励磁機はタービン発電機に電気を供給する装置。月城原発側は励磁機制御カード交換および整備作業を終え、８日午後１０時４３分に発電を再開したと伝えた。タービン発電機は原子炉で作られた蒸気がタービンを通過しながら電気を生産する設備。月城原発の関係者は「今回の故障による放射性物質の外部漏出はない」と明らかにした。
一方、月城原発４号機は昨年６月にもタービン発電機が停止する事故が発生している。当時は蒸気発生器高水位で停止した。
Nuclear Regulatory Commission keen to allow material to be disposed of by ‘land burial’ – with potentially damaging effects
he federal agency providing oversight of the commercial nuclear sector is attempting to push through a rule change critics say could allow dangerous amounts of radioactive material to be disposed of in places like municipal landfills, with potentially serious consequences to human health and the environment.
“This would be the most massive deregulation of radioactive waste in American history,” said Dan Hirsch, president of the Committee to Bridge the Gap, a nuclear industry watchdog non-profit, about a proposal that would permit “very low-level” radioactive waste to be disposed of by “land burial”.
Currently, low-level radioactive waste is primarily disposed of in highly regulated sites in Texas, Washington, South Carolina and Utah. The Nuclear Regulatory Commission (NRC) also provides exemptions allowing “low-level waste” to be dumped in unlicensed disposal sites, but these exemptions are given only rarely, and are conducted with strict case-by-case protocols in place.
The proposed “interpretive” rule change relaxes the rules surrounding how radioactive materials would be disposed of in unlicensed disposal sites “significantly”, said Hirsch.
“If you dump radioactive waste in places that aren’t designed to deal with it, it comes back to haunt you. It’s in the air you breathe, the food that you eat, the water you drink,” he added.
In an email, David McIntyre, an NRC spokesperson, explained that the rule would apply only to a “small subset” of very low-level waste, and that the agency would not allow such disposals “if we felt public health and safety and the environment would not be protected”.
But major sticking point, say experts, concerns how the term “very low-level waste” is not defined by statute or in the NRC’s own regulations.
The NRC describes low-level wastes as contaminated materials like clothing, tools, and medical equipment. According to McIntyre, the radioactivity of “very low-level waste” is just above background. “The radioactivity level of very low-level waste is so low that it may be safely disposed of in hazardous or municipal solid waste landfills,” he wrote.
Nevertheless, “background doesn’t mean it’s safe,” said Diane D’Arrigo, radioactive waste project director for the Nuclear Information and Resource Service, who added that the interpretive rule’s loose language “opens the floodgates” for nuclear waste to be disposed of “as if not radioactive”.
The proposal caps the maximum annual “cumulative dose” to a person from the radioactive wastes dumped into unlicensed sites to 25 millirems – the same limit the NRC uses for highly regulated waste disposal sites. That measurement, said D’Arrigo, is a “projected” amount that can be manipulated through modeling.
[…]
Some environmentalists fear the rule change will also disproportionately impact low-income, marginalized communities who are more likely than their wealthier neighbors to be situated near solid waste landfills.
According to Caroline Reiser, nuclear energy legal fellow with the Natural Resources Defense Council, if the proposal is successfully passed, then the issue could end up in court.
“Once it starts getting implemented, that’s when the real fights end up happening,” she said.
Read more.
By Mutsumi Mitobe
[…]
Many people are opposed to reusing the soil, saying, “It will spread contamination.”
At a news conference on May 1, Environment Minister Shinjiro Koizumi acknowledged, “I strongly recognize the fact that there are people who are opposing (the reuse of decontaminated soil). We will provide detailed explanations to seek understanding for our willingness to take a step forward even if it’s just a small one.”
The project, to start by the end of May at the earliest, will be conducted in the Nagadoro district in Iitate, Fukushima Prefecture. The district is designated as a “difficult-to-return” zone, where radiation levels remain high since the triple meltdown at the Fukushima No. 1 nuclear power plant following the Great East Japan Earthquake and tsunami.
The ministry is seeking to reuse decontaminated soil for public construction work and farmland development if the radiation level of the soil is below certain standards. In the last fiscal year, which ended in March, flowers and crops used to make solid fuel for biomass power generation were grown on land using the decontaminated soil.
The ministry initially planned to revise a related ordinance in April to enable the soil to be reused, saying it obtained “results that showed the soil was safe enough (to be used for growing crops).”
However, the ministry decided to postpone the revision after hearing requests from local residents who want to grow food crops as well. The ministry must check the safety of the soil once again since such crops will be intended for human consumption. The ministry will grow vegetables including tomatoes and cucumbers during the test project.
In the Nagadoro district, there is a demonstration plot of farmland that spans about 600 square meters in total. The land comprises an 800-cubic-meter embankment of soil whose radiation level is 5,000 becquerels or lower per kilogram, and the embankment is covered with uncontaminated soil that is 50 centimeters thick.
Decontaminated soil is currently stored at interim storage facilities in Okuma and Futaba in Fukushima Prefecture. The law stipulates that the final disposal of the soil should be conducted outside the prefecture within 30 years from 2015, when the facilities began storing the soil.
The total amount of soil stored at such facilities is expected to reach about 14 million cubic meters, equivalent to 11 Tokyo Domes, located in Tokyo’s Bunkyo Ward. The ministry is considering reusing the soil to reduce the amount of soil that needs to be disposed of.
Read more.
東京電力福島第1原発事故で避難指示が出た福島県7市町村の1歳児の甲状腺被ばく線量は、市町村別で平均1・2～15ミリシーベルトになるとの研究結果を、国際医療福祉大（栃木県）などのチームが英科学誌電子版に発表した。国連放射線影響科学委員会（UNSCEAR）が2013年に報告した15～83ミリシーベルトより大幅に低くなった。
チーム代表の鈴木元・同大教授（放射線疫学）は「50ミリシーベルト以下は、健康影響が出ることはほとんどなく、がんのリスクを心配する線量ではない」としている。UNSCEAR報告は住民が屋外で一日中被ばくしたと仮定するなど、精度が不十分な面があったという。
チームは避難中の行動を聞き取った福島県の問診票を基に、当時1歳だった7市町村の約900人を、11年3月11～25日の避難日時や経路によって37グループに区分。放射性物質を大量に含む放射性プルーム（雲）の動きや、屋内退避の防護効果などを考慮して被ばく線量を推計した。
市町村別では、南相馬市（小高区）の15ミリシーベルトが最も高く、富岡町の1・2ミリシーベルトが最低だった。
グループ別で最も推計量が高かったのは、南相馬市原町区・鹿島区で避難開始が遅れ、北へ避難したグループで、約20ミリシーベルト。
A nuclear power plant in Byron, Illinois. Taken by photographer Joseph Pobereskin (http://pobereskin.com).
