Monthly Archives: August 2015

"Contaminated rainwater at Fukushima plant repeatedly leaked into sea


FUKUSHIMA — Rainwater containing radioactive contaminants flowed from a drainage ditch by the reactor buildings at the Fukushima No. 1 Nuclear Power Plant into the sea on five occasions in just over four months, it has been learned.

The ditch is 2 meters deep and 2 meters wide, and stretches for about 800 meters. It was created to ferry rainwater from the plant grounds into the ocean, but in February this year it was learned that highly contaminated rainwater from the top of the No. 2 reactor building had flowed into the ditch and subsequently into the ocean. Tokyo Electric Power Co. (TEPCO), the operator of the plant, set up a 70-centimeter-high dam in the ditch, as well as eight pumps to move water from the ditch to another ditch that runs into a sealed harbor area. The pumps, which together can process rainfall of 14 millimeters per hour, were started on April 17 this year.

On April 21, however, loss of power caused by trouble with power generators resulted in all of the pumps shutting down, and contaminated water leaked into the sea. On July 16, rainfall rose to 21 millimeters per hour at one point. This was more than the pumps could handle, and workers confirmed that water flowed into the ocean. In all, five leaks from the ditch occurred in the period between April 17 and Aug. 27.

The concentrations of radioactive cesium and other radioactive materials in the contaminated rainwater ranged from around 20 to 670 times the safety level set for a “subdrain” plan in which decontaminated groundwater is to be released into the ocean.

The volume of leaked rainwater is unknown, but no changes have been seen in radioactive concentrations in the sea near the plant.

The Fukushima Prefectural Government on Aug. 27 issued a new request to TEPCO to introduce leak prevention measures. The next day, TEPCO raised the ditch dam by 15 centimeters, but Naohiro Masuda, chief decommissioning officer at Fukushima Daiichi Decontamination and Decommissioning Engineering Co., says, “Our main countermeasure will be to replace the ditch with a new one.”

This new ditch is designed to carry rainwater into the sealed harbor area. Masuda indicated that until completion of the new ditch — scheduled within the fiscal year — additional leaks may be unavoidable. The plant therefore looks set to enter the typhoon season without full preparations against further leaks.

In February, after the rainwater leaks were discovered, fishermen protested that TEPCO had not released radiation measurements for the drainage ditch water for around 10 months. Negotiations with fishermen over the subdrain plan were subsequently put on hold. However, the Fukushima Prefectural Federation of Fisheries Co-operative Associations officially agreed to the plan after receiving notification from TEPCO and the national government regarding measures to prevent a recurrence of the leaks.

Regarding the rainwater leaks, federation chairman Tetsu Nozaki commented, “All we can do is to ask TEPCO to improve the situation. The subdrain plan is a separate issue, and there is no change in our acceptance of it.”

Source: Mainichi
http://mainichi.jp/english/english/newsselect/news/20150829p2a00m0na019000c.html

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Tochigi town residents rally against selection as candidate site for final disposal of radiation-tainted waste


UTSUNOMIYA – About 2,700 residents of Shioya, Tochigi Prefecture, gathered Saturday to oppose the central government’s choice of the town as a candidate site for the final disposal of some of the radiation-tainted waste resulting from the 2011 Fukushima nuclear disaster.
The residents adopted a resolution urging the plan be scrapped. Among those taking part was Mayor Hirobumi Inomata from Kami, another candidate site in Miyagi Prefecture.
In Tochigi Prefecture, designated waste that contains more than 8,000 becquerels of radioactive cesium per kilogram is currently stored at about 170 different locations on a temporary basis.
For final disposal, the Environment Ministry selected state-owned land in Shioya at the end of July, but the plan has since met strong local opposition.
In 2012, another city in Tochigi Prefecture, Yaita, which borders Shioya, was selected as a candidate site for final waste disposal. However, the government was later forced to reconsider the decision due to fierce local opposition.
The state is planing to build landfill facilities for final disposal in five prefectures — Tochigi, Miyagi, Chiba, Gunma and Ibaraki prefectures — which lack the capacity to dispose of such waste at existing facilities.
In a related move Friday, three nuclear plant makers denied responsibility for the March 2011 Fukushima meltdown at the first hearing on a lawsuit seeking damages from the companies.
Representatives from Toshiba Corp., Hitachi Ltd. and General Electric Co. sought to dismiss the damage claims in Tokyo District Court.
The claims were lodged by about 1,400 people in Japan, including Fukushima residents, and 2,400 people from other places with nuclear plants, such as South Korea and Taiwan.
According to the plaintiffs, the plant makers insisted they have no obligation to compensate for damage from the accident at Tokyo Electric Power Co.’s Fukushima No. 1 nuclear plant, referring to the law on nuclear damage compensation, which stipulates that only power suppliers have responsibilities for nuclear accidents.
The plaintiffs claim that the law, which gives nuclear plant makers immunity from compensation claims, violates the Constitution and therefore is invalid. Under the product liability law and other laws, they are demanding payment of ¥100 each.
Meeting with the press after speaking in court, Kazue Morizono, a 53-year-old resident of Koriyama, Fukushima Prefecture, said she hopes the lawsuit will clarify responsibility for the nuclear accident.
Source: Japan Times
http://www.japantimes.co.jp/news/2015/08/29/national/plant-makers-deny-responsibility-court-fukushima-nuclear-accident/#.VeHRspeFSM9

Morphological defects found in Japanese fir trees around Fukushima nuclear plant


Radiation spewed out by the crippled Fukushima No. 1 nuclear power plant may be responsible for differences in the growth of native Japanese fir trees in the area.
Researchers primarily from the National Institute of Radiological Sciences said Aug. 28 that many fir trees near the plant, as well as other areas, had undergone “morphological defects.”
They intentionally avoided words like abnormality, but used morphological defects and change.
Their studies showed that the changes occurred more frequently in areas with higher air rates of radiation.
“But it is still unclear whether the phenomenon has been caused by radial rays,” a team member concluded, adding that exposure to higher levels of radiation is “one possible cause.”
Conducted in January, the survey covered the town of Okuma in Fukushima Prefecture, located 3.5 kilometers from the plant, where radiation levels of 33.9 microsieverts per hour were detected, and two locations in the town of Namie, also in the prefecture.
While one of the Namie investigation sites is 8.5 km from the plant and measured 19.6 microsieverts per hour, readings of 6.85 microsieverts were detected at the other spot, located 15 km from the facility.
All the sites are within the government-designated difficult-to-return zone, meaning that the residents were evacuated and are prohibited from living there.
The team also examined firs in distant Kita-Ibaraki, Ibaraki Prefecture, which had radiation levels of 0.13 microsieverts per hour, for comparison.
In each of the four sites, the scientists checked 100 to 200 fir trees.
They found that more than 90 percent of firs in the Okuma site were not growing normally. Fir tree boles normally extend upward with two or so branches arising from them horizontally each year. But this was not the case.
Similar changes in shape were found in more than 40 percent of firs and around 30 percent of the trees, respectively, in the two Namie locations. Less than 10 percent of fir trees in the Kita-Ibaraki survey site also were different.
According to the NIRS, findings of studies concerning the 1986 Chernobyl nuclear disaster and other research revealed that conifers, such as firs and pine trees, are vulnerable to the effects of radiation.
However, the scientists noted that the problems reported in their latest survey may have been caused by animals, tree sickness or cold weather, not by exposure to strong radiation.
The Environment Ministry has been examining the impact of radial rays on local ecosystems since the nuclear crisis unfolded at the Fukushima nuclear plant four years ago. The NIRS study is part of those ministry efforts.
The governmental agency has to date monitored 44 kinds of animals and plants in areas around the damaged facility, but no other significant changes or abnormalities have been reported.
‘LABORATORY EXPERIMENTS ESSENTIAL’
Tomoko Nakanishi, a professor of radiation plant physiology at the University of Tokyo, said the latest findings are invaluable as researchers have difficulty doing surveys in the difficult-to-return zone due to high radiation readings.
“There had been so little data on such areas,” she said.
But Nakanishi also pointed out it will require further research to conclude the morphological changes have been caused by exposure to radial rays.
“Other factors may have affected fir trees,” Nakanishi said. “Researchers need to examine through lab experiments what will happen when firs are exposed to high levels of radiation.”
Source: Asahi Shimbun
http://ajw.asahi.com/article/0311disaster/fukushima/AJ201508290045

3 Thyroid Cancer Cases Diagnosed in Kitaibaraki City, Ibaraki Prefecture — Immediately South of Fukushima Prefecture


Kitaibaraki City, Ibaraki Prefecture, is located in the northeastern part of the prefecture, immediately south of Iwaki City, Fukushima Prefecture, and about 70 km south and slightly west of the Fukushima Daiichi nuclear power plant.

On August 25, 2015, Kitaibaraki City released the results of the thyroid ultrasound examination. Below is the English translation of the results and the related newspaper article.

 August 25, 2015
Division of Cooperative Community Development
Office of Health Support

【Regarding the Results of Thyroid Ultrasound Examination Project in Kitaibaraki City】

Kitaibaraki City implemented “Thyroid Ultrasound Examination Project: during the two-year period in Fiscal Year (FY) 2013-2014. (Project expenses: 37,173,000 yen)
Subjects were cityい residents age 0 to 18 at the time of the Fukushima Daiichi nuclear power plant accident. The examination was conducted in those age 0 to 4 in FY 2013 and other ages in FY 2014.
Regarding the examination results, the Kitaibaraki City Thyroid Ultrasound Examination Project Evaluation Council, consisting of experts and physicians, reported as follows:

  1. As screening examination, some would require a detailed examination or be diagnosed with cancer at a fix rate just as expected in a routine health check-up.
  2. The detailed examination result from FY 2014 revealed 3 cases of thyroid cancer.
  3. Radiation is unlikely to be the cause of these thyroid cancer cases.

FY 2013-2014 Thyroid Ultrasound Examination Results

 ※All participants or their guardians received explanations regarding radiation effects, purpose and method of the examination, and diagnostic category at orientation sessions ahead of time.
Those who were assessed to require a detailed examination (B & C diagnostic category) received explanation about the detailed examination during individual home visits.
Second-round screening is planned. The time of screening will be considered based on the opinions of physicians and experts.

Note: Diagnostic criteria employed by Kitaibaraki City are the same as in Fukushima Prefecture according to Oshidori Mako’s inquiry with Kitaibaraki City Hall.

  • A1: no nodules or cysts found
  • A2: nodules ≦ 5.0 mm or cysts ≦ 20.0 mm
  • B: nodules ≧ 5.1 mm or cysts ≧ 20.1 mm
  • C: requiring immediate secondary examination

***************************************************************************************************************
The Asahi Shimbun article dated August 26, 2015

Ibaraki Prefecture: Three Thyroid Cancer Cases in Kitaibaraki City from Last Fiscal Year Examination of Those Age 18 or Younger

Kitaibaraki City has been independently investigating the effect of radioactive substances  due to the Tokyo Electric Fukushima Daiichi nuclear power plant accident on children. On August 25, Kitaibaraki City released the results of the thyroid ultrasound examination conducted in FY 2014 on children age 18 or younger (note: at the time of the accident; at exposure). There were 3 cases of thyroid cancer, but it was judged unlikely to be due to the nuclear power plant accident.

After the nuclear power plant accident, the central government conducted thyroid examination in Fukushima Prefecture, but not in adjacent Kitaibaraki City. Due to requests from parents, the city conducted the examination independently. 1184 children who were age 4 or younger at the time of the accident underwent the examination in FY 2013, and none were diagnosed with thyroid cancer.

Examination subjects in FY 2014 was a total of 6,151 children 18 or younger (including children age 4 or younger who did not undergo the examination in FY 2013). Of these, 3,953 wanted to be examined. The results showed 1,746 with no findings, 1,773 to be followed with observation, 72 to require detailed examinations, and 2 to require detailed examinations immediately. 3 were diagnosed with thyroid cancer by the Thyroid Ultrasound Examination Project Assessment Council. However, the cancer was determined unlikely to be due to radiation exposure owing to the Fukushima nuclear power plant accident, considering the supposed exposure dose and the length of time since the accident. 


According to tweets by a freelance journalist Ryuichi Kino who contacted the Office of Health Support, Division of Cooperative Community Development, Department of Citizen Welfare at Kitaibaraki City Hall, 3 cancer cases were diagnosed from 74 (72 in category B and 2 in category C) who had detailed examinations, but apparently 2 cases who were in diagnostic category C were not automatically diagnosed with cancer. (It is unclear if this means the 2 “C” cases were eventually diagnosed with cancer after the detailed examination, or they were not diagnosed with cancer). All 3 have been operated on and apparently doing well. The city has no intention of releasing ages and sexes of the three patients, as such information might identify the individuals. Names of the Kitaibaraki City Thyroid Ultrasound Examination Project Evaluation Council members will not be released at the request of some of the members. The Council consists of 6 members — 1 thyroid specialist, 3 physicians including surgeon(s) and general practictioner(s), and 2 city officials. According to the Ibaraki Shimbun article, president of Kitaibaraki City Hospital, Dr. Yoshifumi Uekusa, stated, “Symptoms began to appear 5 years after the Chernobyl accident, and the exposure dose is less in Japan, so it is unlikely to be due to radiation effects.”  Apparently, Dr. Uekusa is a member of the Council. 

Oshidori Mako contacted Kitaibaraki City Hall and reported that the Thyroid Ultrasound Examination Project Assessment Council (which concluded, “Radiation is unlikely to be the cause of these thyroid cancer cases”) included no experts in radiation protection or dose estimation. Oshidori Mako also noted that the radioactive plume blew in the south towards Iwaki City but the lack of precipitation prevented radionuclides from depositing on the ground as it did in Iitate Village. (This means the overall radioactivity of soil may not be high, but residents still might have been exposed to the radioactive plume when it passed through the area). The early exposure dose assessment, based on the soil deposition, has been inadequate for a place such as Iwaki City. 

As a matter of fact, paragraph C43 of UNSCEAR 2013 discusses the so-called “south trace” having much higher ratios of Te-129m and I-131 to Cs-137. This suggests a significant amount of radioactive iodine isotopes might have fallen in the “south trace” which includes Iwaki City. As Kitaibaraki City is immediately south of Iwaki City, and the air movement does not stop at the border between the two cities, it is possible for Kitaibaraki City to have received a similar amount of the radioactive plume as Iwaki City.

Source:  Fukushima Voice version 2
 http://fukushimavoice-eng2.blogspot.fr/2015/08/3-thyroid-cancer-cases-diagnosed-in.html

Morphological defects in native Japanese fir trees around the Fukushima Daiichi Nuclear Power Plant


Abstract

After the accident at the Fukushima Daiichi Nuclear Power Plant (F1NPP) in March 2011, much attention has been paid to the biological consequences of the released radionuclides into the surrounding area. We investigated the morphological changes in Japanese fir, a Japanese endemic native conifer, at locations near the F1NPP. Japanese fir populations near the F1NPP showed a significantly increased number of morphological defects, involving deletions of leader shoots of the main axis, compared to a control population far from the F1NPP. The frequency of the defects corresponded to the radioactive contamination levels of the observation sites. A significant increase in deletions of the leader shoots became apparent in those that elongated after the spring of 2012, a year after the accident. These results suggest possibility that the contamination by radionuclides contributed to the morphological defects in Japanese fir trees in the area near the F1NPP.

Introduction

During the Fukushima Daiichi Nuclear Power Plant (F1NPP) accident that occurred in March 2011, radionuclides that were released into the atmosphere contaminated the surrounding environment1,2. Since the accident, much attention has been paid to the biological consequences of contamination by radionuclides. To detect the biological changes in the environment, various wild organisms, such as Japanese monkeys3, lycaenid butterflies4, and gall-forming aphids5, inhabiting the surrounding area have been investigated as possible indicator organisms. However, further studies using radiation-responsive indicator organisms help us to reach a consistent conclusion, whether radiological contamination from the F1NPP accident had a biological impact on the environment.
For the purpose of biomonitoring of the radiological contamination, nevertheless, coniferous plants have been demonstrated to be suitable indicator organisms because of their high radiosensitivity, which was revealed decades ago by field examination using gamma irradiation facilities6,7,8,9. Radiosensitive damages in conifers were reported after the Chernobyl nuclear accident in 1986, where two local coniferous species, Scots pine (Pinus sylvestris) and Norway spruce (Picea abies), showed distinct biological damage in the radioactively contaminated areas10,11,12. Under experimental and accidental exposure, morphological changes, particularly in branching of the main axis, were shown to be the most frequently observed radiosensitive responses of coniferous plants6,7,8,9,10,11,12.
Coniferous tree species are grown in the area highly radioactive contaminated by the F1NPP accident, where Japanese fir (Abies firma) is one of the most common naturally grown species. Different from other coniferous species, young-tree populations of Japanese fir are abundant, because this species has the characteristic ability to sprout even on the shaded forest floor. The short height of young trees enables the easy observation of morphological changes in the whole tree. In addition, the regular annual branching of Japanese fir trees enables determination of the year that any morphological changes occurred through a number of past years (Fig. 1).

 In this study, we used the Japanese fir tree as an indicator organism to detect the environmental impact of radiological contamination caused by the F1NPP accident. We examined the morphological changes in annual leader shoots for the past five years within the highly contaminated area around the F1NPP13. The investigation was carried out in January 2015 at 3 observation sites (S1, S2, and S3), at different distances from the F1NPP and with different contamination levels (Fig. 2, Table 1). The three observation sites were situated in “Area 3” where it is expected that the residents have difficulties in returning for a long time (Ministry of Economy, Trade and Industry). Fir trees were also examined in a slightly contaminated control site (S4), southwest of the F1NPP.

Results

Most of the naturally grown Japanese fir trees showed a typical monopodial branching pattern to form a trunk with one main axis (Fig. 3A), whereas some trees showed distinctive morphological defects on the main axis of the trunk (Fig. 3B,C). Independently of the growing site, these defects were characterized by irregular branching at the whorls of the main axis with a distinct deletion of the leader shoot that normally elongates vertically to form the main axis. The space of the deleted leader shoot was filled in by the remaining lateral branches that either extended upwards (Fig. 3B) or retained their horizontal position (Fig. 3C).

 The overall frequency of the morphological defects of the main axis varied among observation sites, S1, S2, and S3, but it was significantly higher in each site compared to the control, S4 (chi-square test with df = 1, p = 2.1 × 10−58, 3.7 × 10−17, and 8.1 × 10−7, respectively, Bonferroni-corrected; Fig. 4). The frequency corresponded to the ambient dose rate at the observation sites that represented the local levels of radionuclide contamination (S1 > S2 > S3 > S4, Table 1). A high frequency of defects was observed in S1, where 125 out of 128 trees showed branching defects of the main axis.

 Branching defects of the main axis were analyzed separately in each annual whorl (Fig. 5). Compared to the whorls of 2010, which had been generated before the F1NPP accident, the frequency of deleted leader shoots was significantly increased in the whorls after 2012 (sites S1 and S3), or those after 2013 (site S2). The frequency peaked in the whorls of 2013 and tended to decrease in the whorls of 2014 in every observation site. The variation patterns in the series of annual whorls were similar among the sites, whereas no annual variation was observed in the control site, S4. These results indicated that the deletion of leader shoots occurred most frequently in the whorls that elongated from terminal winter buds during the growing season of 2012–2013.

 Despite the significant increase in the frequency of deleted leader shoots in annual whorls around 2013 in the observation sites S1–S3, the number of lateral branches that elongated from the same whorls did not show annual variation that corresponded to the deletion frequency of leader shoots (Fig. 6). The number of lateral branches was not different among annual whorls even in S1 (one-way ANOVA, p = 0.84), in which the frequency of leader shoot deletions varied most intensely compared to the other observation sites (Fig. 5). On the other hand, the number of lateral branches showed significant annual variation in S2, S3, and S4 (one-way ANOVA, p = 1.4 × 10−7, 6.3 × 10−3 and 1.5 × 10−8 for S2, S3, and S4, respectively); however, the annual variation patterns were independent from the frequency of leader shoot deletions. In addition, the variation in lateral branch number among the sites did not correspond to the frequency variation of deleted leader shoots. This indicated that the deletion of leader shoots occurred independently of the change in lateral branch number that elongated from the whorls.

 Differences in the development of the leader shoots and lateral branches were also observed from a close inspection of the defected whorls. At each site, the deleted leader shoots left no marks among normal lateral branches (Fig. 7A). Similar structures were also observed in the winter buds of 2015 at the top of the main axis, where normal lateral buds with completely deleted apical buds were sometimes observed (Fig. 7B). These observations demonstrated that the deletion of leader shoots probably resulted from the deletion of apical buds at an early stage of their development, independently of the formation of lateral buds.

 Discussion

  1. In this study, significant increases in the morphological defects were shown in Japanese fir populations growing in areas near the F1NPP. The occurrence corresponded to the radioactive contamination level represented by the ambient dose rate in each site, suggesting that the defects could be due to the exposure to ionizing radiation from the radionuclides released after the accident.
    On the other hand, deletion of leader shoots was also observed in the control site at a lower frequency, indicating that the defects were not radiation-specific, but universal. The deletion of leader shoots in the control site occurred randomly in the annual whorls and not specifically in a certain year. Moreover, even in the highly contaminated sites, a low frequency of defects was observed before the F1NPP accident in 2011. These results suggested that the defects could also occur independently of radiation exposure.
    Similar defects of the main axis have been reported in many coniferous species grown in plantations and involve the separation of trunk into two or more stems of similar size, which is called a forking defect14,15,16,17. Forking defects can be caused by breakage of the leader shoot due to an accidental damage, such as bird perching, animal attack, wind damage, and pathogenic disease, or due to environmental stress such as frost14. Previous studies have shown that in lodgepole pine (Pinus contorta), the forking defects could also be caused by physiological control of apical dominance even in the absence of mechanical damage14,15. In this study, the observed forking defects in Japanese fir were identical to those in other coniferous tree species.
    In relation to radiation effects, deletion of the leader shoots has been reported in Scots pine trees chronically exposed to radiation in a contaminated area close to the Chernobyl nuclear power plant11. The trees that showed forking defects with deletion of annual leader shoots eventually formed bushy canopies without a main axis. Another study showed that Scots pine trees in Chernobyl were characterized by the disappearance of a single trunk and replacement with two or more trunks or branches, corresponding to the estimated dose rate during the development of apical buds12. Although the defects in pine trees close to the Chernobyl nuclear power plant were not all identical to the defects observed in Japanese fir trees in the area close to the F1NPP, the information seems to support the relationship between the morphological changes in Japanese fir and the chronic exposure to radiation from released radionuclides.
    Despite the correlation between the defects in Japanese fir and the radioactive contamination level, there is little biological information to support the contention that the increased frequencies of the morphological changes were due to radiation released after the F1NPP accident. Even though the damage at the early stage of apical bud formation is suggested as the main cause of the deletion of leader shoots, there was an inexplicable 2-year time lag between 2011, the year with the highest radiation dose in the environment, and 2013, the year with the highest frequency of defects. Consequently, processes at the cellular and tissue level involved in the deletion of leader shoots need to be elucidated in relation to the development of lateral and apical buds in coniferous plants.
    As described above, there are several factors that are possibly responsible for increased frequencies of the morphological defect observed in Japanese fir populations near the F1NPP, and, at present, there is no decisive evidence that any single factor is causally related to these increased frequencies. However, a positive correlation was observed between ambient dose rates and frequencies of the morphological defect, and these frequencies increased after the F1NPP accident while they were much lower before the accident, suggesting that, of several potential factors, ionizing radiation is most likely to have increased frequencies of the morphological defect. To confirm this contention, dose rates to Japanese fir should be estimated in contaminated fields of Fukushima, and effects of long-term irradiation on this tree should be investigated in irradiation facilities.

    Methods

    Plant and field observations

    Samples of Japanese fir were examined in 4 sites (3 observation sites and 1 control site) in the Abukuma region dominated by the Abukuma Highlands and a series of gentle hills leading to a narrow plain along the east coast of Pacific Ocean (Fig. 2, Table 1). Climate conditions in this region are commonly cold with little snow during the winter. The vegetation in the examined sites was mostly mixed forests of Japanese fir trees with other dominant trees such as Japanese red pine (Pinus densiflora), and oak (Quercus serrata) (Table 1). The investigation of fir trees was performed between January 5 and 9, 2015, approximately 4 years after the F1NPP accident in March 2011. At the time of investigation, fir trees were in their dormant season when each branch has apical and lateral buds at the top (Fig. 1).
    All the fir trees between 0.4 m and 5 m in height were observed within 8–12 quadrats (10 × 10 m) placed in each examined site. Five whorls from the top of the main axis were observed. The occurrence of deleted leader shoots and the number of lateral branches were determined in each of annual whorl. The counts and the number in all the quadrats within each site were pooled before analysis.

    Measurement of ambient dose rate

    The ambient dose rate was measured at the centre and corners within each quadrat at 1 m above ground level with either an ionization chamber-type survey meter (ICS-323C, Hitachi Aloka Medical, Tokyo) for S1 or a NaI scintillation survey meter (TCS-172, Hitachi Aloka Medical, Tokyo) in S2, S3, and S4. The measurements were averaged within each site to determine the representative value of the ambient dose rate in the site.

    Statistical analysis

    Data were analyzed using Excel 2007. Comparisons between the groups were performed using Fisher’s exact test or the Chi-squared test.

    Additional Information

    How to cite this article: Watanabe, Y. et al. Morphological defects in native Japanese fir trees around the Fukushima Daiichi Nuclear Power Plant. Sci. Rep. 5, 13232; doi: 10.1038/srep13232 (2015).

    Source: Nature.com
    http://www.nature.com/articles/srep13232

Cleanup starts in Fukushima’s restricted zone


Japanese Govenment insisting on making priorly evacuated people to return to live in highly contaminated areas

 

Full-scale decontamination work has begun in one of the areas in Fukushima Prefecture that received the highest doses of radioactive fallout from the 2011 nuclear accident.

About 30 workers gathered at an elementary school in the town of Okuma on Friday. They used heavy machinery to remove top soil from the playground.

Okuma partly hosts the Fukushima Daiichi nuclear plant. The government has determined that some parts of the town will remain restricted areas where people will not live for an extended time.

In these restricted zones, decontamination work had only been carried out on an experimental basis.

But at the request of town officials, the Environment Ministry decided to launch full-scale cleanup work targeting a district where there are a lot of schools and public facilities.

The ministry plans to finish decontaminating the roughly 95-hectare area by next March.

Similar restricted zones exist in 6 other municipalities in Fukushima.

Ministry officials plan to decide whether to start decontaminating them after checking their radiation levels and the wishes of the residents. 
Source: NHK 
http://www3.nhk.or.jp/nhkworld/english/news/20150828_38.html

Government mulls new subsidies for communities near decommissioned nuclear reactors


The Ministry of Economy, Trade and Industry plans to seek ¥4.5 billion in the government’s fiscal 2016 budget to provide financial assistance to local communities facing reductions in existing subsidies following the decommissioning of nuclear reactors, ministry sources said Wednesday.

New support measures are necessary as some aging reactors are to be decommissioned, the sources said.

The operational period for nuclear reactors is limited to 40 years in principle. They can then operate a further 20 years if approval is given by the Nuclear Regulation Authority, but the requirements to extend operations are tough and maintenance costs are high.

In April, a decision was made to decommission five aging reactors, including the No. 1 and No. 2 reactors at Kansai Electric Power Co.’s Mihama plant in Fukui Prefecture, located in central Japan.

As a result of the decommissioning decision, the local governments in those areas will see a decline in the subsidies they are given for fiscal 2016 under the current program for support to communities hosting nuclear plants.

The National Governors Association is calling on the central government to continue providing support to host local communities until the dismantling of decommissioned reactors is completed.

The planned support program is expected to help finance new measures to shore up local economies near such reactors, the sources said.

Meanwhile on Wednesday, the Fukushima Prefectural Government decided to subsidize moving expenses for those who wish to return home after vacating areas outside of the designated evacuation zones after the March 2011 disaster.

To support those who aim to return to Fukushima, the prefectural government plans to offer financial assistance of up to ¥100,000 per household, the officials said.

The government has allocated ¥376 million for such expenses in a supplementary budget for September for some 5,200 households, with the aim of providing such support within the year.

“I’m taking seriously the current situation,” Fukushima Gov. Masao Uchibori told a news conference.

According to the prefectural government, the number of people who left areas that were not affected by evacuation advisories following the nuclear disaster at Tokyo Electric Power Co.’s wrecked Fukushima No. 1 plant was estimated at some 25,000 as of the end of last year.

The subsidy is expected to be offered to those who have already returned to Fukushima, on condition that they lived in temporary housing for two years or longer.

In June, the Fukushima government decided it would stop providing free housing under the disaster relief law at the end of fiscal 2016, when the financial support on moving expenses is scheduled to end as well.

It also plans to offer housing aid for low-income earners who move from temporary housing to privately rented housing for some two years starting in fiscal 2017.

Source: Japan Times
http://www.japantimes.co.jp/news/2015/08/27/national/government-mulls-new-subsidies-communities-near-decommissioned-nuclear-reactors/#.VeCVMpeFSM_