Archive for October, 2013

The Fate of the Australian Nuclear Veterans Claim for Justice

October 30, 2013

http://www.greens.org.au/nuclear-veterans

JUSTICE FOR NUCLEAR VETERANS

The Greens want nuclear veterans to receive the same health care as other veterans over 70.
WHAT YOU NEED TO KNOW

1892 veterans were exposed to radiation by British Nuclear Testing between 1952 and 1963, but a technicality stops them from getting the Gold Card health care other veterans over 70 receive.
Nuclear veterans suffer a 23% greater chance of having cancer than the general population and an 18% greater chance of dying from cancer.
In addition to cancers, nuclear veterans and their families have suffered birth defects and miscarriages, and other disorders such as anaemia and bronchial disease.

Less than $30 m per year is a small price to pay for the health care they deserve in old age.
The Greens support the case before the Australian Human Rights Commission on behalf of 290 veterans who claim their human rights were violated.
The Australian government knew about the dangerous radiation that would be dispersed from British Nuclear Testing.
We are running out of time to exercise our duty of care to these Australians.

VETERANS AFFECTED BY BRITISH NUCLEAR TESTING

Australians exposed to nuclear tests were done a great wrong. It is time we showed care for our nuclear veterans. These veterans are aging and should not incur further indignity due to an inability to pay medical costs, nor the further expense and delay of pursuing long-overdue justice.

Australian servicemen, often clad only in shorts and t-shirts, were exposed to nuclear tests while the British scientists in charge looked on wearing protective full body suits.

These veterans have paid a terrible price in terms of radiation-induced illness, suffering a 23% greater chance of having cancer than the general population and an 18% greater chance of dying from cancer.i

The Australian Greens will provide Australian veterans exposed to radiation from British nuclear weapons testing at the Montebello Islands, Maralinga and Emu Fields between 1952 and 1963 with the Gold Card to cover all medical care.

While other veterans over 70 years of age who experienced combat automatically receive the Gold Card, nuclear veterans currently do not because their injuries and illnesses were incurred from the actions of an ally rather than from an enemy or combat situation.

Nuclear veterans are required to prove their health problems are directly linked to radiation exposure from decades ago. Despite being exposed to very high levels of radiation, it is almost impossible to prove concretely that the tests caused an individual’s illnesses. Therefore, the Department of Veterans Affairs very seldom accepts their condition as caused by the tests.
THE NUCLEAR TESTS

The British detonated 12 nuclear weapons in Australia – three on the Montebello Islands in Western Australia (1952-56), seven at Maralinga (1956-7) and two at Emu Fields (1953) in South Australia. Nine tests were conducted over Christmas and Malden Islands (1957-8). Between 1960 and 1963, an estimated 22 kg of plutonium, uranium and other fission products were dispersed around Taranaki, the most contaminated of the test sites at Maralinga.

Radioactive fallout from the Montebello tests swept across the continent, reaching inland Queensland coastal towns and across to Fiji. Fallout from Maralinga reached Adelaide and Melbourne.

According to the Comprehensive Test Ban Treaty Organisation, approximately 16,000 Australian civilians and servicemen were exposed to nuclear fallout.ii
THE GREENS’ PLAN

For a small sum — $85.2 million over the forward estimates — the remaining 1,892 Australian nuclear veterans could be provided the same benefits and entitlements that other veterans are awarded.

The independent Parliamentary Budget Office has estimated providing the Gold Card to all defence personnel participants from 1 July 2014 would cost less than $30 million per year.

We would provide the Department for Veterans Affairs additional staffing of 2.75 FTE to administer implementation, for a cost of $0.4 million over the forward estimates.

Given the devastating impact on their lives and their families, this is a small price to pay.

We are running out of time to exercise our duty of care to these Australians. People should need only to prove that they were exposed to high levels of radiation as a result of the weapons testing in order to get the Gold Card.

http://www.greens.org.au/sites/greens.org.au/files/Nuclear_veterans.pdf

Radioactivity of Uranium 237

October 28, 2013

Finding the rate of radioactivity of Uranium 237 – the synthetic isotope which does not occur in any significant amount in nature – but which was first discovered during photo-fission experiments with uranium in Japan in 1940 – is very difficult.

Before emailing Oak Ridge, I asked Andrew Kishner, who writes:

“Hi Paul,
It’s great to hear from you.

I used a ‘specific activity calculator’ – which you can find online – and determined U-237’s activity is 81,615 Ci/g.

That value uses the following inputs:
[Uranium 237]
Atomic mass: 237.048724
Half-life: 6.75 days

I double-checked the value using an old-school formula (you can find that formula way down the page at this URL http://nuclearcrimes.org/conversions.php).

It’s works out the same.

I hope this helps! ”

Thanks Andrew. Certainly does. It’s another of the disappearing “magic bullets”. Kept secret by the USA during the H bomb era and by Britain too. Not surprising as the large amount of natural U in the tampers and Neutron reflectors in those bombs was turned to U 237 by neutron exposure during the blasts. A major source of early dose according to Lapp.

The British H bomb veterans have not heard of it and I am informed. And the Ministry of Defence maintain the uranium fallout on Christmas Island was harmless.

However:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3171289/

Proc Jpn Acad Ser B Phys Biol Sci. 2011 July 25; 87(7): 371–376.
doi: 10.2183/pjab.87.371
PMCID: PMC3171289
The discoveries of uranium 237 and symmetric fission — From the archival papers of Nishina and Kimura
Nagao IKEDA*1†
Editor: Toshimitsu YAMAZAKI
Author information ► Article notes ► Copyright and License information ►
Go to:
Abstract

Shortly before the Second World War time, Nishina reported on a series of prominent nuclear physical and radiochemical studies in collaboration with Kimura. They artificially produced 231Th, a member of the natural actinium series of nuclides, by bombarding thorium with fast neutrons. This resulted in the discovery of 237U, a new isotope of uranium, by bombarding uranium with fast neutrons, and confirmed that 237U disintegrates into element 93 with a mass number of 237.”

Mr Abe, Nishina rolls in his grave at your stupidity.

As for local heroes, this is way over the frontal lobes of the South Australia Minister for public works who claimed, when minister for mines, in March 2011 in front of an audience of uranium mining execs on a junket at the Hilton Hotel (The Pay Dirt Conference) “No-one will dies from Fukushima Diiachi.”

The Lancet has not published the Minister’s speech yet.

Though Dr Yamashita, the dude appointed to initially head the monitoring of the health of Fukushima children responded by concocting a new, unique in the world, minimum latent period for thyroid cancer in children of “4-5 years”. A position maintained by the Fukushima Medical university ever since.

Wonder when Yamashita is going to get around to amending his 1998 paper on the matter. He visited Chernobyl many many times. And noted at in his paper that thyroid cancer in Belarus and Ukraine appeared “very rapidly” after the disaster at Chernobyl. He also noted that once induced by the reactor “accident”, the rate of growth of the cancers was “rapid”.

Breathtaking revisionism from Japan’s Mr Chernobyl. And of course, when Yamashita cite’s Chernobyl as a precedent, which he does, he cites himself. And he knows of course that his post 3/11 crap is absolutely contradicted by his own published peered reviewed paper of 1998.

The endocrine system is most important in mediating the body’s response to the damage inflicted by radiological insult.

Kids who have had heir thyroid glands removed would seem to be at a disadvantage in this regard.

During the 1970s the number of new cases of childhood thyroid cases per year was less than 20. For the whole of the nation of Japan.

Since March 2011, the number of new cases of childhood thyroid cases, as determined by Dr Yamashita and the Fukushima Medical University, has totaled 44 (to September 2013). Not for the whole nation of Japan, but merely for the cohort of children living in the affected area of Fukushima Prefecture.

Yamashita and the Fukushima Medical University maintain that none of the afflicted Fukushima children contracted their cancers due to radiological insult from the nuclear disaster of March 2011.

These authorities justify their position by citing Chernobyl research, which, they claim, proves that thyroid cancer in areas close in affected by the Chernobyl reactor disaster did not contract thyroid until after 4 years had elapsed.

Consulting the record shows that Yamashita himself observed that early onset childhood thyroid in Ukraine and Belarus post Chernobyl occurred very rapidly and that once invoked, those cancer grew very rapidly.

Fukushima Medical University staff engaged in the Thyroid health survey of Fukushima children cite sources based on Chernobyl data which the staff claims support 1. A long 4-5 year latent period for thyroid cancer 2. A slow progression of the disease. In fact these sources actually confirm that latent periods in early onset cases of the disease post Chernobyl were very short, and these sources report that disease progression in the early onset cases post Chernobyl was rapid. The authors of these Chernobyl reports include Dr S. Yamashita, formerly of the Fukushima Medical University Fukushima Thyroid Health Survey.

“Childhood thyroid cancer: comparison of Japan and Belarus.
Yamashita S, Shirahige Y, Ito M, Ashizawa K, Motomura T, Yokoyama N, Namba H, Fukata S, Yokozawa T, Ishikawa N, Mimura T, Sekine I, Kuma K, Ito K, Nagataki S.:
“tumors arising in the Chernobyl population began developing with surprising rapidity and short latency.” (Yamashita et. al., 1998, pdf page 2, journal page 204). The authors consider this rapid onset of disease to be notable compared to thyroid cancers which occurred prior to the Chernobyl nuclear accident.


Source: Center for Cancer Control and Information Services,
National Cancer Center, Japan

Matsuda A, Matsuda T, Shibata A, Katanoda K, Sobue T, Nishimoto H and The Japan Cancer Surveillance Research Group. Cancer Incidence and Incidence Rates in Japan in 2007: A Study of 21 Population-based Cancer Registries for the Monitoring of Cancer Incidence in Japan (MCIJ) Project. Japanese Journal of Clinical Oncology, 43: 328-336, 2013 Download Source Data as Excel spreadsheets at http://ganjoho.jp/pro/statistics/en/table_download.html

. http://link.springer.com/content/pdf/10.1007/BF02035773.pdf
Deposition of gamma-emitting nuclides in Japan after the reactor-IV accident at Chernobyl‘

Journal of Radioanalytical and Nuclear Chemistry
Volume 116, Issue 2 , pp 291-306
Cover Date 1987-12-01
Authors

M. Aoyama (1)
K. Hirose (1)
Y. Sugimura (1)

Author Affiliations

1. Geochemical Laboratory, Meteorological Research Institute, Nagamine 1-1, Yatabe, 305, Tsukuba, Ibaraki, (Japan)

Abstract

The wet and dry deposition of gamma-emitting nuclides are presented for Tsukuba and eleven stations in Japan following the nuclear reactor accident at Chernobyl’. In Japan fallout from the reactor at Chernobyl’ was first detected on May 3, 1986, a week after the accident. Abruptly high radioactive deposition, which mainly consists of131I,132I,103Ru,137Cs and134Cs, was observed in early May. The cumulative amount of131I,103Ru and137Cs in May at Tsukuba were 5854±838 Bq·m−2, 364±54 Bq·m−2 and 130±26 Bq·m−2 (decay was corrected to April 26), respectively. The monthly137Cs deposition in May corresponds to 2.5% of the cumulative137Cs deposition during the period from 1960 through 1982. Most of the Chernobyl’ radioactivities, especially131I, are scavenged from the atmosphere by the wet removal process. end quote.

I have a question for the Fukushima Medical University. When did nuclear industry commence in Japan?

http://en.wikipedia.org/wiki/T%C5%8Dkai_Nuclear_Power_Plant

“The Tōkai Nuclear Power Plant (東海原子力発電所 Tōkai genshi-ryoku hatsuden-sho?, Tōkai NPP) was Japan’s first nuclear power plant. It was built in the early 1960s to the British Magnox design, and generated power from 1966 until it was decommissioned in 1998. A second nuclear plant, built at the site in the 1970s, was the first in Japan to produce over 1000 MW of electricity.”

Impact of I131 on Native Americans from era of nuclear weapons tests

October 22, 2013

Impact of I131 on Native Americans from era of nuclear weapons tests

Disease risk persists for more than the half life of a radionuclide:

Risk Analysis Vol 20, No. 1, 2000

“The Assessment of Radiation Exposure In Native American Communities from Nuclear Weapons Testing in Nevada”

Eric Frohmberg, Robert Goble, Virginia Sanchez and Dianne Quigley

Abstract: “Native Americans residing in a broad region downwind from the Nevada Test Site during the 1950s and 1960s recieved significant radiation expopsures from nuclear weapons testing. Because of differences in diet, activities and housing, their radiation exposures are only very imperfectly respresented in the Department of Energy dose reconstructions. There are important missing pathways, including exposures to radioactive iodine from eating small game. The dose reconstruction model assumptions about cattle feeding practices across a year are unlikely to apply to the native communities as are other model aussumptions about diet. Thus exposures from drinking milk and eating vegetables have not yet been properly estimated for these communities. Through consultation with members of the affected communities, these decificiencies could be corrected and the dose reconstruction externded to Native Americans. An illustration of the feasibility of extending the dose reconstruction is provided by a sample calculation to estimate radiation exposures to the thyroid from eating radio-iodine contaminated rabbit thyroids after the Sedan nuclear test. The illustration is continued with a discussion of how the calculation results may be used to make estimates for other tests and other locations.” end quote.

http://www.cancer.gov/cancertopics/causes/i131/abouti131

US National Cancer Institute download page with links to the following pages and download:

* About I-131
* How Americans Were Exposed
* The Milk Connection
* The Government’s Response
* I-131′s Rapid Breakdown
* Key Facts
* Get the Facts About Exposure to I-131 Radiation (Brochure)
* Get the Facts About Exposure to I-131 Radiation (Presentation)
* I-131 and Thyroid Cancer – Flip Chart for Native Americans (PDF)

Text from
I-131 and Thyroid Cancer – Flip Chart for Native Americans
Quote:
Am I at risk?
The amount of I-131 people absorbed depended on:
1. Their age during the testing period (between 1951 and
1963)
2. The amount and source of milk they drank in those years
3. Where they lived

6. People born between 1936 and 1963
People with the highest risk of developing thyroid
cancer from exposure to I-131 were children during the
period of atomic bomb testing, and are now 40 years of
age or older.
• People younger than 15 at the time of testing (between
1951 and 1963) probably have a higher thyroid cancer
risk from exposure to I-131 fallout than other people.

Milk drinkers

Children’s thyroid glands were smaller and still growing
when they were exposed to I-131. And children were
more likely to have consumed milk, which could have
exposed them to I-131.
• Babies who were breastfed may have been exposed to
two to three times as much I-131 as their mothers. But if
their mothers did not drink large amounts of fresh milk,
babies likely received little additional exposure from
breast milk.
• Babies who drank formula or condensed milk were not
exposed at all.
• People received little exposure from eating fruits and
leafy vegetables as compared to drinking fresh milk.
This is because I-131 fell on the surface of the fruits and
vegetables. So peeling or washing them removed most of
the I-131. Little I-131 was transferred to the inside of the
plant.

The amount of milk people drank played a role in how
much I-131 they were exposed to. So did the source of
the milk.
• Fresh milk from backyard or farm cows and goats usually
contained more I-131 than store-bought milk. This is
because processing and shipping milk allowed more time
for the I-131 to break down.
• Goat’s milk generally contained more I-131 because
goats concentrate significantly more I-131 in their milk
than cows do.

Where did I-131 go?

Where people lived as children is another risk factor.
• I-131 was carried thousands of miles away from the test
site by winds.
• Because of wind and rainfall patterns, the distribution
of fallout varied widely after each test. Therefore, certain
areas of North America received more fallout than other
areas.
• Scientists think that the largest amount of I-131 fell over
parts of Utah, Colorado, Idaho, Nevada, and Montana.
But I-131 traveled to all states, especially those in the
Midwest, East, and Northeast United States.

Exposure to I-131 may increase a person’s risk of getting
thyroid cancer.
• Thyroid cancer accounts for less than 2 percent of all
cancers diagnosed in the United States.
• Most of the time, thyroid cancer is a slow-growing
cancer. With treatment, it can usually be cured.

The United States is not Fukushima.

You may want to visit a doctor based on 4 key factors:
1. Age—if you are 40 or older, especially if you were born
between 1936 and 1963
2. Milk drinking—if you drank a lot of milk as a child,
especially milk from farm or backyard cows and goats
3. Where you lived as a child—if you lived in the
Mountain West, Midwest, East, or Northeast U.S.
4. Medical signs—if you have a lump in your thyroid
gland
People who think they may be at risk for thyroid cancer
should discuss this concern with their doctor. The doctor
may suggest a schedule for checkups.

NIH Publication No. 02-5286
Printed September 2002

end quote

Latent time is much more important than half life time in determining onset date range of radiogenic disease. Diminishing rates of radionuclide presence does not represent to a static population reducing risk – the risk is established by the total exposure. Thus, in 2002, publication date of the quoted document, weapons test fallout exposure to I131 was still causing
disease onset. The publication remains relevance, even though it is more than 8 days since the last atomic bomb was detonated by the United States upon its own people.

Japan may well attempt to control information by equating Fukushima with nuclear bomb testing, however the Japanese government cannot justify its own current exposures of its people to the fallout of radionuclides from Fukushima on the basis of the false belief that nuclear weapons testing was harmless, for it patently was not harmless. And that false assumption is patently at the core of the recent public statements made by members of the Japanese elite in the past week.

If the Japanese government is attempting to use the same techniques used by the Western nuclear powers to quell voters during the period of nuclear weapons testing, the method hopefully will backfire. Assuming voters in Japan don’t have short memories.

Thyroid Surgery video. What nuclear advocates consider normal and routine for kids.

October 22, 2013

Japan Mayor Offers Fukushima Kids Home in His Town

October 22, 2013

http://abcnews.go.com/International/wireStory/japan-mayor-offers-fukushima-kids-home-town-20641685

ABC News USA.

Japan Mayor Offers Fukushima Kids Home in His Town
MATSUMOTO, Japan October 22, 2013 (AP)
By YURI KAGEYAMA Associated Press

A generation ago, Dr. Akira Sugenoya performed lifesaving cancer surgery on more than 100 children after the 1986 Chernobyl catastrophe. Today, as mayor of a central Japanese city, he’s trying to avoid a repeat of his own history.

Beginning in April, parents living in the shadow of the Fukushima nuclear disaster will be able to send their children about 300 kilometers (200 miles) away to his city, Matsumoto, to go to school. The city will pay 14 million yen ($140,000) a year for a six-bedroom house and caretakers; parents won’t pay tuition but will cover expenses such as utilities and meals.

“If my fears turn out to be unfounded, nothing would be better news,” Sugenoya said in a recent interview with The Associated Press at Matsumoto city hall. “But if they become reality, then there is little time before it’s too late.”

Sugenoya has been critical of the government’s response to the three meltdowns at the Fukushima Dai-ichi nuclear plant, which exploded after the March 2011 tsunami and is still releasing radiation into the air and sea. Decommissioning will take decades, and experts disagree over how much the disaster will affect the health of area residents.

The single sickness confirmed by the International Atomic Energy Agency to have been caused by low-dose radiation from Chernobyl is thyroid cancer, which if properly treated with surgery is rarely fatal. Sugenoya, a thyroid specialist, volunteered to work in Belarus, close to the Ukraine power plant, in 1991 after hearing about thousands of cases of thyroid cancer there.

Five years later, he quit his job at a prestigious Japanese hospital and returned for another five and a half years. He has set up a donation fund for Chernobyl victims and regularly brings doctors from Belarus into Japan for training.

It’s unclear how the radiation leaks near Fukushima Dai-ichi compare with those from Chernobyl. Measuring exposure at the individual level involves complex calculations to account for the daily intake of food and water, and can vary greatly.

The Japanese government has detected 44 confirmed and suspected cases of thyroid cancer among 217,000 youngsters, 18 and under, checked in Fukushima prefecture (state). Thyroid cancer among children is generally rare, estimated at only one in a million. The link to radiation is still inconclusive, and extensive testing of Fukushima children could account for the higher numbers.

Children are far more sensitive to radiation-caused diseases than adults because their bodies are developing, but their bodies can bounce back and heal from the damage of radiation. Sugenoya said that in areas of Belarus that are close to Chernobyl, children are periodically sent away from radiated areas.

Matsumoto, in Nagano prefecture, has about 240,000 people, and has room in its schools because of the declining population common in rural areas. Sugenoya’s plan, called the Matsumoto Project, will be open to Fukushima students from third grade to junior high school.

Matsumoto officials have conducted meetings in Fukushima to explain the plan, and some parents have expressed interest, but it is unclear how many of them will send their children away to study.

Fukushima residents most worried about radiation are already gone. Some 150,000 people have left areas in Fukushima most ravaged by the tsunami, a third of them to other prefectures.

About 200 of them are in Matsumoto, including Hiroshi Ueki, his wife and their children, 6 and 4.

“They ask me, ‘Can I now touch the flowers?'” Ueki said of his children. “In Fukushima, they had to wear masks, and they became afraid. They were getting scolded a lot. ‘Don’t touch any dirt.’ ‘Don’t touch this.’ ‘Don’t touch that.'”

Some who remain in areas surrounding the wrecked nuclear plant are torn over whether to stay.

Yuri Hasegawa, a 45-year-old Fukushima mother, is so worried she has bought a Geiger counter and has a stockpile of masks. She cooks with only food that has been tested for radiation.

She has been sending her two children, 9 and 13, to summer and winter camps in the northernmost island of Hokkaido, the southernmost island of Okinawa, and the southwestern city of Hiroshima. She is thinking about taking part in the Matsumoto Project. She said she faces opposition from her husband and other relatives, who scoff at her concerns as extreme.

In her backyard and other areas, “The Geiger counter starts going beep, beep, beep, beep,” she said. “The beeps are coming so fast. You know radiation is going through our bodies. It’s because it’s invisible. If we could see it, we wouldn’t be living here.”

The Japanese government says it is safe to live in areas that have not been forced to evacuate, but it also has admitted errors in responding to the radiation danger.

Shortly after the tsunami, the government could have doled out potassium iodide pills to block children’s thyroids from accumulating radioactive iodine. It had the pills, but failed to deliver them in time to be effective, and it has acknowledged that it was not properly prepared.

The government also has acknowledged that it failed to effectively use data that accurately forecast where radioactive plumes were headed. While a zone around the nuclear plant was cleared, residents beyond the zone who were in the predicted paths of the plumes were not warned.

Sugenoya, a slightly built man with a gentle smile, said his offer is intended to help concerned families play it safe.

“Radiation doesn’t hurt. It doesn’t even itch,” he said. “A terrible thing has happened, but people don’t realize it at all.”

———

Follow Yuri Kageyama on Twitter at twitter.com/yurikageyama

Prof Kosuke Noborio, Meiji University. “The Fight Against Radio Cesium in Soil”

October 22, 2013

http://www.meiji.ac.jp/cip/english/after311/interview/interview_04.html

Kosuke Noborio
Department/ School Professor, Department of Agriculture, School of Agriculture (Laboratory of Land Resources)
Bio Dean, Meiji University Graduate School of Agriculture (2010-2012);
Councilor, Institute of Soil Physics (2009-2011, 2011-2013);
Director, Soil Physics Research Division, The Japanese Society of Irrigation, Drainage and Rural Engineering (2009-2011)
Degree Ph.D., Texas A&M University (http://www.tamu.edu/)
Research themes Soil Physics / Environmental Physics

Quote:
“Temporary Decontamination would be a never ending process.

My area of expertise is soil physics and environmental physics. Thus far I have been engaging in efforts to develop measuring methods for early detection of organic contaminants leaked into soil and to prevent contamination of groundwater.

Due to the nuclear power plant accident, the soil in surrounding areas was contaminated with radioactive cesium. I had hoped to come up with a way to apply my research up to that point to restore the cesium-contaminated soil, however, in reality, things were not so easy.

A research group was formed comprising researchers at Meiji University, University of Tokyo, and Shimane University to discuss how to reduce radiation levels. A method on how to decontaminate farm land that had been contaminated by cesium was also in our minds. However, upon visiting the actual contamination site in June, we realized that this method was merely a theory and nothing else.

First, we did not anticipate the contaminated area being situated deep in the mountains. I had originally imagined the area to be normal farmland on level ground, but actually the contaminated area was in a small area of level ground where produce is cultivated, nestled between some mountains. No matter how many times we decontaminate such a small area of farmland in the mountains, it would be a never-ending process, as contaminants would soon flow back again from the mountains behind it.

Therefore, we developed a new plan. The plan was to dig holes around the edges of the mountains and try to stave off the cesium there. We would dig vertical holes about several centimeters in diameter and 50 cm deep around the edges of the mountains and bury glass fiber there. Water contaminated by cesium would flow down the mountains into the holes and be guided underground by the glass fiber. This should reduce the level of radiation on the surface. This idea was adopted by Meiji University as an earthquake reconstruction project.

However, upon arriving at the contaminated site, this idea too turned out to be unrealistic. Clearing the trees, digging holes, and filling them with glass fiber would take up incalculable time and effort.

Therefore, we considered a method to dig, not holes, but ditches around the mountains to gather water. In this way, we might prevent recontamination of decontaminated land around the center of the flatland area, away from the mountains. However, there were houses that were built near the edges of the mountains, and after considering whether these houses would remain livable, this idea was also deemed not realistic.

Cesium does not bond to clay as much as expected.

There were still more unanticipated issues.

It was reported that after removing fallen leaves from the mountains, radiation levels in that area fell immediately. This meant that cesium in the atmosphere had fallen on the leaves that covered the surface of the mountains. Therefore, raking the fallen leaves would have a temporary effect on lowering radiation levels. However, cesium does not bond to fallen leaves. In other words, the cesium was merely on the leaves in a water soluble form. This meant that while we could collect the cesium that just happened to be on the fallen leaves we raked, the cesium on the leaves still left on the mountains would dissolve into water when it rained, sinking into the surface and flowing underground. Of course, there was no way to rake up all the leaves in the mountains—and if we could, there would still be the following problem.

The fallen leaves that were raked up as samples to investigate for decontamination were placed into bags and gathered in one place. However, high radiation levels were detected in the place the leaves were gathered. Becoming alarmed, we took just one bag of leaves to take back for further analysis, but the bag by itself did not show a high level of radiation. It was simple addition. The more bags of leaves there were, the higher the level of radiation. If you think about it, it is only natural, but it came as a surprise to us researchers upon actually experiencing it. You can easily imagine how high radiation levels could get if we gathered all of the fallen leaves on the mountains.

Even so, we held an optimistic view that even if decontamination proved difficult, the effect of cesium on produce would naturally disappear in a few years. One of the properties of cesium is to bond to clay. Therefore, we believed that even if the cesium were to remain in the soil, in a few years it would bond to clay and not be absorbed by produce.

However, looking at the results of our survey, we found that the speed with which cesium bonds to clay was actually a lot slower than we had theorized. In reality, there was a possibility that it would not bond as much as we had anticipated, and we could not sit around waiting for cesium to naturally bond to clay.

Because our previous plan to channel cesium-contaminated water into the ground was also based on the theory that cesium would bond to clay underground and not contaminate groundwater, we needed to further our investigations. The cesium that was on the fallen leaves would dissolve in water when it rained, and some of that water would remain in the soil without bonding to clay. Eventually, that cesium might flow into the fields or contaminate groundwater.

In fact, in places where there was grass or moss near ditches by the side of the road in which water from the mountains gathered, we recorded higher levels of radiation than in other places. These areas were storing concentrated levels of cesium.

Currently, our research group visits the site every week, along with the Fukushima Saisei no Kai (Fukushima revitalization group) comprising mainly University of Tokyo alumni, to set radiation level gauges in various places. By continuing to monitor the gauges, we will be able to find out the speed with which radiation levels are diminishing naturally. Through these activities, we should be able to make an estimate on how many years it would take before life can return to the way it was before.

At present, we have yet to find a way to speedily restore the cesium-contaminated soil. However, if only to be able to present a forecast for disaster victims, we will continue with our research.

Forest Fire Situation in Japan

October 20, 2013

http://www.fire.uni-freiburg.de/iffn/country/jap/jap_1.htm
Forest Fire Situation in Japan
(IFFN No. 26 – January 2002, p. 54-60)

By
Tobias Zorn, Global Fire Monitoring Center (GFMC), Fire Ecology Research Group, Max Planck Institute for Chemistry c/o Freiburg University P.O. Box 79085 Freiburg GERMANY and
Kouji Nakayama and Osamu Hashiramoto Forestry Agency Japan 1-2-1 Kasumigaseki Chiyoda-ku Tokyo, 100-8952 JAPAN

Introduction

Forests are deeply embedded in Japanese culture. This is not only represented by abundant traditional wooden buildings. Many tree reserves around temples and shrines indicate the high value of trees and forests. With 25 million ha of forests, corresponding to a forest cover rate of 67 percent, Japan is one of the most densely forested countries in the world (Japan FAO Association 1997).
The territory of Japan extends from 20° N to 46° N with climatic features ranging from subtropical to boreal conditions. The overall climatic conditions are characterized by high precipitation and a generally mild climate. During the winter, the continental high-pressure weather system is dominant, replaced in summer by the Pacific high-pressure system. The onset of monsoons in June-July and at the end of September coincide with this change of high-pressure areas. Annual rainfall is between 1 000 and 4 000 mm (Forestry Agency Japan 1990).
Stretching over 3 000 km, the archipelago of Japan consists of four major islands, Hokkaido, Honshu, Shikoku and Kyushu. Mountainous and hilly areas cover about 75 percent of the land area. Mountain slopes are generally very steep and dissected by short rivers of all sizes. Forestry is concentrated in mountainous regions with steep terrain, which makes forest firefighting countermeasures difficult and complex. Because of the scarcity of flat land, these areas are suitable for farming and settlement (Forestry Agency Japan 1990, Japan FAO Association 1997, Ota 1993; The National Land Afforestation Promotion Organization 1991).
The climax vegetation is forest, reflecting the warm monsoon climate with high precipitation. However, the species composition and the distribution of forest types differ from region to region because of marked climatic differences in Japan’s long, narrow land area and also because of complex differences in topography, geology and soil. These forests are classified into four types or zones: (1) sub-frigid (including sub-alpine), (2) cool temperate, (3) warm temperate, and (4) subtropical (Japan FAO Association 1997).
The sub-frigid forest zone (also called sub-alpine forest where its occurrence is governed by height above sea level) is located in the mountains of central Honshu and in central Hokkaido. In northeastern Hokkaido it occurs even close to sea level. The dominant tree species are white fir (Abies mariana), yezo spruce (Picea jezoensis), Glehn’s spruce (Picea glehnii) and, in Honshu, Veitch fir (Abies veitchii), northern Japanese hemlock (Tsuga diversifolia), and hondo spruce (Picea jezoensis var. hondoensis).
The cool temperate forest zone is characterized by the beech belt (Fagus crenata; in Japanese, buna). This type of forest occurs at elevations higher than 1 000 m above sea level in Kyushu, at 600 m around the Kanto district (greater Tokyo and Yokohama) and at sea level from the central part of Honshu north to western Hokkaido. Other tree species are Japanese lime tree (Tilia japonica), Japanese horse chestnut (Aesculus turbinala), katsura tree (Cercidiphyllum japonicum), and Japanese walnut (Juglans ailanthifolia).
The warm temperate forest zone itself is characterized by laurel (Machilus thunbergii), live oak (Quercus phylliraeoides), and camphor tree (Cinnamomum camphora).
In addition to these three main zones, a subtropical forest zone is found in Okinawa and in the southwestern part of Kyushu Island.

The forest fire situation in Japan

Influenced by its climatic and topographic conditions, it is a widely accepted perception that natural disasters such as floods and landslides are common in Japan (Forestry Agency Japan 1994). Despite the humid climate, the annual number of forest fires often exceeds 4 000, affecting an average area of more than 4 000 ha in the 1980s and 2 300 ha in the 1990s (Tab.1 and 2).


Source: Forestry Agency Japan (2000).


Source: Forestry Agency Japan (2000).


Figure 1. Number of forest fires by causes in Japan in the period 1976 to 1988. Source: Forestry Agency (2000)


Figure 2. Number of forest fires by causes in the period 1989 to 1998 in Japan. Source: Forestry Agency Japan (2000).

Figure 3 shows that 99 percent of the wildland fires are human-caused (Nakagoshi et al. 1987), such as from the misuse of fire during afforestation and cultivation, bonfires, campfires, playing with fire, burning of rubbish, cigarettes, matches and fire works.


Figure 3. Causes of forest fires in Japan related to the number of fire incidents.

Explanation: “Setting a brush fire” (Japanese: hiire) may include setting a prescribed fire (NTT 1999). Open-air fires include fires set at the occasion of Obon (Festival of the Dead), a Buddhist ritual that is celebrated annually in July (Western Julian calendar) or August (Chinese lunar calendar), depending on the location. For several consecutive evenings, in the cemetery next to the temple, family members hang lit paper lanterns or deposit lighted candles. Wind and animals (often crows) are some of the reasons for the spread of fire into the open landscape.
In the early spring season (due to the longitudinal range of the chain of the islands the spring season stretches over two and a half to three months, from February in Kyushu to May in Hokkaido), a lot of dry litter is accumulated on the forest floor and the forest floor itself is also dry. Since rainfall or downpours usually accompany thunderstorms, lightning is rarely a fire cause in Japan. The occurrence of fires is highly correlated to human activities in this densely populated country. Propagation of forest fire is highly influenced by weather, human activity and forest conditions. As Figure 4 shows, the frequency, the distribution over the year and the number of forest fires is high during the season with the lowest precipitation and relative humidity and during the months when outdoor activities are high.
Most of the broadleaved forests do not burn easily. Because of the generally cool and wet weather conditions, only a few forest fires occur in the sub-alpine conifer forests. Forest fires are more common in western Japan, where secondary forests of Pinus densiflora are widely distributed. Pine forests (P. densiflora, P. thunbergii and P. lutchuensis) tend to burn easily.

Fire control organization

In Japan, the fire services of cities, towns and villages are responsible for wildland fire suppression. For large fire situations support systems are available (Tab. 3 and 4), such as dispatch of the fire services of neighbouring cities, towns and villages and the Japan Self-Defence Forces.

Table 3. Fire services of cities, towns and villages in 1998.
Municipal Agencies Number
Fire prevention headquarters 920
Fire departments 1 662
Fire houses 3 232
Fire brigades 3 643
Fire squads 25 393

Source: White Book on Fire Service in Japan (1998).


Figure 4. Distribution of the number of fire incidents over the year
(5-year average between 1994-1998). Source: NTT (1999).

Table 4. Forest fire protection facilities subsidized by the Government of Japan

Water tanks 3 694
Natural water supply facilities 21
Aerial fire–fighting supply bases 12
Forest fire-fighting equipment
Fire defence radios 1 743
Receivers 1 340
Chainsaws 290
Portable sprayers 24 150
Portable water dischargers 297
Light portable pumps 96
Utility vehicles 118
Water trucks with small water pumps 23
Brush Cutters 1

To ensure that adequate fire-fighting capability can be deployed to forest fires, the Agency has developed fire defence support systems for large areas, is promoting the use of helicopters for information collection and aerial fire-fighting and provides guidance to prefectures and municipalities on timely requests for wide-area assistance. Helicopters are increasingly used for detection and communication in addition to being used in aerial fire suppression, including the use of fire retardants (White Book on Fire Service in Japan 1998).

Fire defence program for special forest fire regions

Since 1970 the Fire and Disaster Management Agency has been promoting a special forest fire defence programme in high risk areas in cooperation with the Forestry Agency. In municipalities bordering large areas of forest where there is a high risk of fire, the fire defence program includes the following measures:

Forest fire prevention through public education, patrols and monitoring;

Forest management with regard to fire prevention, such as the establishment and maintenance of firebreak belts;

Establishment of communication systems;

Development and improvement of fire fighting facilities;

Restriction of fire use during the fire season; and
Fire fighting training.

By 1997, this programme had been implemented successfully in 226 areas involving 940 municipalities in 38 prefectures (White Book on Fire Service in Japan 1998).
The early deployment of helicopters for reconnaissance and fire-fighting is an important concept in Japan. Further use of this strategy, in which helicopters work in close cooperation with ground firefighting operations, will require the development of additional bases for helicopter operations. In addition, water tanks and other water supplies are required for use during forest fires, especially in regions where residential areas are adjacent to forests and homes are at risk. There is a need to establish and continually update forest fire defence plans covering essential items about forest fire characteristics and firefighting operations. These plans allow firefighters to accurately grasp the state of a forest fire, determine firefighting tactics, deploy firefighting resources effectively and ensure reliable communications and a sufficient supply of water in the affected area. The effective use of simulation systems based on these forest fire defence plans has to be ensured.

Forest fire prevention campaign

A joint initiative by Fire and Disaster Management Agency and the Forest Agency, the national forest fire prevention campaign is held in conjunction with the spring national fire prevention campaign to raise public awareness and increase the effectiveness of fire prevention. This yearly educational campaign focuses on spreading the forest fire prevention message through educational activities aimed primarily at hikers, local residents and primary and junior high school students; banners and posters placed in stations, municipal offices and at the entrances to mountain routes; advertisements in the various media services, fire prevention training and study meetings.

end quote.

One wonders how much cesium and other fission and fuel product will be re-entered into the atmosphere from forest fires in Japan given the above forest fire statistics.

See also:

https://nuclearhistory.wordpress.com/2013/10/20/contaminated-forests-management-after-chernobyl-and-fukushima/

https://nuclearhistory.wordpress.com/2013/10/20/forests-around-chernobyl-have-been-absorbing-radioactive-elements-a-fire-would-send-them-skyward-again/

https://nuclearhistory.wordpress.com/2013/10/20/main-investigation-results-on-the-forest-radioecology-in-the-kyshtym-and-chernobyl-accident-zones/

Main investigation results on the forest radioecology in the Kyshtym and Chernobyl accident zones.

October 20, 2013

http://www.ncbi.nlm.nih.gov/pubmed/7839123

Sci Total Environ. 1994 Dec 11;157(1-3):45-57.
Main investigation results on the forest radioecology in the Kyshtym and Chernobyl accident zones.
Tikhomirov FA, Shcheglov AI.
Source

Moscow State University, Russian Federation.
Abstract

As a result of the long-term studies of radionuclide migration in forest ecosystems in zones of radioactive contamination after the Kyshtym and Chernobyl accidents, the following trends were revealed: (1) High retention capacity of stand canopy with respect to radioactive fallout. This leads to high doses absorbed by apical and leaf meristems, beta-radiation giving the main part of the dose; (2) Fast self-decontamination of crowns during the growth period and relatively slow decontamination in the phase of physiological rest, regardless of amount of atmospheric precipitation. The rate of crown decontamination determines the value and duration of radiation stress on woody plants; (3) Accumulation not less than 95% of the total radionuclide amount in the forest litter 1-2 years after the cessation of radioactive fallout; (4) Relatively slow migration of strontium and cesium radionuclides along the forest soil profile; (5) High capacity of the forest when serving as a biogeochemical barrier to the routes of horizontal and vertical radionuclide migration and export out of the zone of initial contamination, including migration into the river water; (6) Considerable difference between strontium and cesium when migrating in forest soils and in the soil-plant system; (7) Broad variations in transfer factors for uptake of cesium-137 from soil into forest plants depending on the plant species and soil type. The primary radiobiological effects connected with irradiation of organisms are considered and secondary disturbances due to changes of ecological bonds between the components of irradiated forest ecosystem are discussed.

PMID:
7839123
[PubMed – indexed for MEDLINE]

Forests around Chernobyl have been absorbing radioactive elements. A fire would send them skyward again

October 20, 2013

http://wwwp.dailyclimate.org/tdc-newsroom/2013/06/chernobyl-forest-fire

At Chernobyl, danger lurks in the trees


Chernobyl reactor Nos. 5 and 6 were under construction at the time of the No. 4 explosion and remain frozen in time. But forests in the Chernobyl Exclusion Zone have been absorbing radioactive elements since the 1986 accident, and scientists fear a wildfire could trigger another release. Photo © Jane Braxton Little.

June 24, 2013
For 27 years, forests around Chernobyl have been absorbing radioactive elements. A fire would send them skyward again – a growing concern as summers grow longer, hotter and drier.

By Jane Braxton Little
The Daily Climate

CHERNOBYL, Ukraine – Most days Nikolay Ossienko patrols the forests surrounding the Chernobyl nuclear power plant, clearing brush and dead trees from the grid of fuel breaks that crisscross the 1,000-square-mile area. But on hot July afternoons, when black thunderheads loom on the horizon, he climbs a rusty ladder 75 feet up a rickety fire tower. When he spots smoke, he radios the six other towers to pinpoint the location, then trucks off to the blaze.

“Our number one job is to save the forest from fire,” said Ossienko, a burly, blue-eyed Ukrainian whose warm smile winks with a missing tooth.

It’s a job with international consequences. For almost three decades the forests around the shuttered nuclear power plant have been absorbing contamination left from the 1986 reactor explosion. Now climate change and lack of management present a troubling predicament: If these forests burn, strontium 90, cesium 137, plutonium 238 and other radioactive elements would be released, according to an analysis of the human health impacts of wildfire in Chernobyl’s exclusion zone conducted by scientists in Germany, Scotland, Ukraine and the United States.

This contamination would be carried aloft in the smoke as inhalable aerosols, that 2011 study concluded.

And instead of being emitted by a single reactor, the radioactive contamination would come from trees that cover some 660 square miles around the plant, said Sergiy Zibtsev, a Ukrainian forestry professor who has been studying these irradiated forests for 20 years.

“There’s really no question,” he added. “If Chernobyl forests burn, contaminants would migrate outside the immediate area. We know that.”
Overcrowded pines

Combined with changes in climate, these overcrowded pines are a prescription for wildfire. In their assessment of the potential risks of a worst-case fire, Zibtsev and the team of international scientists concluded that much of the Chernobyl forest is “in high danger of burning.”

Zibtsev has been worrying about catastrophic wildfire in Chernobyl since witnessing runaway wildland fires in the western United States while on a Fulbright Scholarship in 2005. He has watched the threat get worse each passing year. Rainfall in the region is decreasing and seasonal droughts are lasting longer, changes Zibtsev attributes to climate change. Scientists say these patterns of drier and longer summers are contributing to forest drying and increased insect attacks.

The predominantly pine forests themselves are part of the problem. After the explosion – the worst nuclear accident in human history – the area surrounding the power plant was evacuated, the fields and forests abandoned. To keep the contamination from moving beyond the area known as the “zone of alienation,” the Ukraine government forbade all commercial activity. For forests, this meant a halt to logging, thinning and removing dead trees. While most of Ukraine boasts woodlands that are carefully manicured, the Chernobyl forests have grown into unmanaged thickets with dense brush below and lifeless canopies above.

The risk of fire in these forests has concerned scientists since 1992, a drought year when more than 65 square miles of forests burned. They know that these ecosystems are trapping radionuclides and slowly redistributing them in soil and vegetation, a process called “self-repair.” In some places the contamination level is the same as it was in 1986, most of it in the top 10 centimeters of the soil. Absorbing cesium, plutonium and strontium helps contain radionuclides within the exclusion zone, but it dramatically heightens the alarm over wildfire.
Two-acre test fire

A 2002 test fire offers insight on the scope of the radioactive risk. Set to assess plume and radionuclide behavior, the two-acre ground fire near the failed power plant released up to five percent of the cesium and strontium in the biomass. A high-intensity crown fire would release much higher amounts than burning needles and leaf litter, said Vasyl Yoschenko, who set the fire and heads the radioecological monitoring laboratory at the Ukrainian Institute of Agricultural Radiology. Other studies predict that the fine particles emitted from a forest fire could be transported hundreds of miles away.

“Imagine going to bed at night knowing something like this could happen,” said Chad Oliver, director of the Global Institute of Sustainable Forestry at Yale University, who has studied the region since 2005.

Oliver, Zibtsev and others began calling attention to the potential for another Chernobyl disaster at variety international and scientific conferences, but the issue drew little more than finger pointing. Until their 2011 study, no one had assessed the human health effects of a catastrophic wildfire in the exclusion zone.
A worst-case scenario

Led by Oliver and Zibtsev, scientists at several institutions in Europe and North America analyzed a worst-case scenario: A very hot fire that burns for five days, consumes everything in its path, and sends the smoke 60 miles south to Kiev. A separate worst-case study is underway looking at the risks for Sweden, Finland and other European countries heavily impacted by the 1986 explosion.

Women in their 20s living just outside the zone face the highest risk from exposure to radioactive smoke, the 2011 study found: 170 in 100,000 would have an increased chance of dying of cancer. Among men farther away in Kiev, 18 in 100,000 20-year-olds would be at increased risk of dying of cancer. These estimates pale in comparison to those from the 1986 Chernobyl explosion, which predict between 4,000 and over a million eventual deaths from radiation exposure.

Instead, the greatest danger from forest fire for most people would be consuming foods exposed to smoke. Milk, meat and other products would exceed safe levels, the 2011 study predicts. The Ukrainian government would almost certainly have to ban consumption of foodstuffs produced as far as 90 miles from the fire.
No need for evacuation

After years of anxiety, the results of the study surprised Oliver. People living outside the exclusion zone would not have to be evacuated. There would be no cause for panic in Kiev, he said.

But the predictions for Ossienko and his fellow firefighters are not so rosy. They would be exposed to radiation beyond all acceptable levels. In addition to “normal” external radiation, they would be inhaling radionuclides in the smoke they breathe – being irradiated both outside and inside.

On top of the significant health risks, these crews are utterly unequipped to fight large fires, Zibtsev said. At Ossienko’s fire station near the Belarus border, four well-maintained fire trucks gleam inside a shed, all ready to roll. But the fire lanes designed to get them to a blaze quickly are untended, often blocked by fallen trees and brush. Ossienko is proud of the Soviet tank modified for firefighting with a 20-foot blade like a gigantic pointed cow-catcher. He says it can “crush trees and brush – anything.” But reporting smokes by climbing fire towers is no one’s idea of an early-warning system, and the lone helicopter occasionally available lacks even a bucket for dropping water on a fire.
‘They’re obviously not prepared’

The firefighters themselves are dedicated and hard working, Zibtsev added, but they don’t have much professional training, protective suits or breathing apparatuses – standard equipment for American firefighters dealing with hazardous materials. “They’re obviously not prepared for a major wildfire situation,” he said.

The United Nations recently acknowledged the potential for another Chernobyl disaster and has mounted a $20 million sustainable development project designed to address wildfire and other environmental issues.

The UN project recognizes – “finally!” said Zibtsev – that well-managed forests will contribute to the decrease of fire hazards within the region. Zibtsev, who is responsible for the program’s fire management system, and Oliver envision a four-pronged approach that starts with cutting trees out of the roads so firefighters have access. Modern firefighting and fire detection equipment should dramatically improve fire response time. And then? “Start thinning!” Zibtsev said.

All this will take time, said Oliver: “If we can live out 30 to 40 years and not have a big one, we might be a lot safer.”

Meanwhile, Ossienko is at work in the heat of the Chernobyl summer, watching for smoke and, with the rest of the world, hoping for none.

Texts and photographs © Jane Braxton Little, 2013. All rights reserved.

Jane Braxton Little is an independent journalist and photographer based in California’s northern Sierra Nevada. Her travel to Ukraine was funded by a grant from the Fund for Environmental Journalism, a project of the Society of Environmental Journalists.

Photos, from top: Brush, vines and undergrowth have taken over much of the forest in the Chernobyl exclusion zone, enveloping even houses; Firefighter Nikolay Ossienko; Forestry professor Sergiy Zibtsev; Fire trucks at the ready; A Soviet-era tank modified for firefighting, at the Chernobyl fire station near Belarus.

The Daily Climate is an independent news service covering climate change, energy and the environment. Contact Douglas Fischer at dfischer [at] DailyClimate.org

Contaminated forests: Management after Chernobyl and Fukushima

October 20, 2013

http://thebulletin.org/contaminated-forests-management-after-chernobyl-and-fukushima

Bulletin of the Atomic Scientists, 1 August 2013.
Written by Winifred BirdJane Braxton Little

Deep in the forested mountains of Fukushima Prefecture, in the town of Kawauchi, a woman in an apron and skirt stands in front of her house, solemnly scrutinizing her property. A group of workmen, crouched nearby drinking their afternoon tea, have cleared the property of all underbrush and grass. Beyond them a dry brown expanse slopes 20 meters up the hillside, its trees now branchless trunks poking upward between fresh-cut stumps.

The woman is one of thousands of residents and temporary workers who are using chainsaws, bamboo rakes, and their own hands to remove leaf litter, undergrowth, and trees from the periphery of houses and other buildings throughout the eastern part of the prefecture. Their target is anything that might harbor contamination from the March 2011 meltdown of three reactors at the Fukushima Daiichi Nuclear Power Station. Japanese officials believe that scouring the land will rid it of radionuclides so that evacuees can safely move back home. But while decontamination has already been declared finished in one town within the exclusion zone and is under way in others, vast stretches of heavily forested mountains—up to 86 percent of the land in some districts near the plant—are proving a major obstacle in the government’s cleanup and resettlement plan.

At Chernobyl, Ukraine, the site of the only nuclear accident worse than this one, government officials have taken an entirely different approach to managing irradiated forests. After Chernobyl’s No. 4 reactor exploded in 1986, sending radionuclides aloft as far as Sweden and Finland, officials completely evacuated 2,600 square kilometers. In this area, known as the exclusion zone, forests now cover 87 percent of the land. Left to themselves, the abandoned forests and fields trapped cesium, plutonium, strontium, and other airborne radionuclides through their natural life cycle: Contamination-coated leaves and needles dropped to the ground, where they became part of the litter and gradually migrated into the soil. In 2006, scientists found that up to 96 percent of all radionuclides remaining in the forests were concentrated in the soil, mostly in the top 10 centimeters.

Cesium around Fukushima is also migrating from trees and leaves into the soil. When scientists at the government-funded Forestry and Forest Products Research Institute surveyed the distribution of radiocesium at three forested sites in the fall of 2011, they found between a third and half of contaminants were in the leaf litter. Removing these fallen leaves, they suggested, would be a relatively efficient way to clean up forests. By the time the researchers re-tested the same three sites a year later, however, contaminants had shifted dramatically downward: Between 65 and 77 percent of radiocesium was in the soil, where it is much more difficult, expensive, and environmentally harmful to remove.

While officials in Japan grapple with these issues, their counterparts in Ukraine are struggling with one of the consequences of their decision to let nature take its course in the Chernobyl exclusion zone: fire. If these forests burn, strontium-90, cesium-137, plutonium-238, and other radioactive elements would be released, scientists say. And instead of being emitted by a single reactor, the radioactive contamination would come from trees covering a vast area. A worst-case-scenario study conducted in 2011 predicted that people living outside the exclusion zone would not have to be evacuated, and there would be no cause for panic in Kiev. But firefighters would be exposed to radiation beyond acceptable levels. In addition to external radiation, they would be exposed to internal radiation by inhaling radionuclides in the smoke.

Forest scientists in Japan say the risk of catastrophic forest fires in Fukushima is relatively low compared with Ukraine, and limited to a short dry season in spring. Nevertheless, the Chernobyl data present yet another dilemma for Japanese officials and forest residents.

As the sites of the world’s worst nuclear power plant accidents, Japan and Ukraine share the challenge of protecting their citizens even as they hope to return residents to the rural communities where forests sheltered and nurtured them. Whether Japan opts for the Chernobyl model, leaving forests to their slow but natural recovery, or pursues decontamination, local residents will inevitably pay a price.

Editor’s note: A grant from the Society of Environmental Journalists covered the authors’ travel costs for this article.