Clean up of Maralinga Nuclear Test site, enabling return of Aboriginal owners, return completed 2012. Nuclear tests 1956-1964. Note 5 mSv annual dose limit, 10 mSv intervention limited (ICRP 1999) Note particle count limit per hectare. Note risk factor at these limits. Compare with Japanese official attitude that doses below 100 mSv pa pose no risk.
THE CLEAN-UP CRITERIA
The aim of the Maralinga rehabilitation was to ensure that the risk to potential inhabitants from exposure to radioactive contamination would be acceptable. The dividing line between acceptability and unacceptability of risk [TAG, 1990] was determined to be an annual committed dose of 5 mSv, assuming full time occupancy by Aborigines living an outstation lifestyle. This corresponds to an annual risk of fatal cancer following the inhalation or ingestion of contaminated soil of not more than 1 in 10,000 by the fiftieth year of life [TAG, 1990]. The value of 5 mSv is broadly consistent with the intervention level of 10 mSv that has recently been proposed by the International Commission on Radiological Protection [¤6.1 in ICRP, 1999] and which is under consideration by the International Atomic Energy Agency [IAEA, 2002]. Both of these international bodies are proposing that, in future, a generic reference level of around 10 mSv be set, under which intervention is generally not justified.
Two actions were undertaken to achieve this limitation of possible radiation dose. First, where levels of radioactivity were so high that a dose of 5 mSv could be received in a short time, the contamination would be removed and safely buried in disposal trenches. In areas where there was no acute hazard but permanent occupation could result in doses exceeding 5 mSv, restrictions on land-use would be imposed.
When determining the soil removal criteria, MARTAC took into account three dose pathways, inhalation of resuspended dust, ingestion of soil or contaminated food, and wound contamination. There were thus two main requirements for defining the criteria for soil removal. The first was the concentration of plutonium in the surface soil, which would be available for resuspension and inhalation. This criterion was stated as the maximum quantity of 241Am per unit surface area, taking account of the Pu/Am activity ratios and the enhancement factors. The second was a limit on the number and activity of contaminated particles and fragments near the surface. These had the potential to be accidentally eaten or to cause or contaminate a break in the skin of a potential inhabitant.
The Maralinga Technical Advisory Committee (MARTAC) established three sets of criteria for levels of contamination that were to be permitted to remain following rehabilitation [Cooper et al., 1997; Williams et al., 1998].
1 Soil-Removal Criteria: At Taranaki, contaminated soil (or the offending contamination itself) was to be removed where the levels of dispersed 241Am exceeded 40 kBq/m2 averaged over 1 hectare (10,000 m2) or where contaminated particles exceeding 100 kBq were found, or where the density of particles exceeding 20 kBq was greater than 1 in 10 m2.
2 Clearance Criteria: Where soil was removed, the residual levels of dispersed contamination in the cleared area was not to exceed 3 kBq/m2 241Am averaged
1 over 1 hectare and particulate contamination was to meet the Soil-Removal Criteria.
2 Unrestricted Land-Use Criteria: Permanent occupancy and unrestricted land-use was only to occur where levels of dispersed contamination were less than 3 kBq/m2 241Am averaged over 3 km2, and the particulate contamination met the Soil-Removal Criteria.
For the dose conversion factors accepted for general use at the time, and the site-specific factors applying at Taranaki, the concentration of 241Am in the surface levels of soil of 3 kBq/m2 was expected to lead to an annual dose of 5 mSv through inhalation of contaminated dust, under conditions of continuous occupancy [Lokan & Williams, 1995]. Realistic scenarios for other exposure pathways showed the doses involved to be no more than 10% of this.
MARTAC criteria for the removal of contaminated particles and fragments states that no particles of 241Am activity greater than 100 kBq and no observable contaminated fragments should remain outside the soil-removal contour or within the rehabilitated area at the conclusion of the operation. There should also be no more than an average of one discrete particle of activity greater than 20 kBq per 10 m2.
MARTAC did not specify any averaging criterion for particles of 20 kBq or below, but 0.1 per square metre or 1 per 10 square metres was not very practical. ARPANSA interpreted this criterion as requiring that there be fewer than 1000 particles exceeding 20 kBq 241Am per hectare.
It is the view of more than one international radiation decontamination expert that the official Japanese attitude toward inhalation dose vectors present in Japan as a result of the Fukushima Diiachi nuclear disaster is grossly under estimated.
“In July 2011, Fukushima Collective Evacuation Trial wasfiled by secondary school mothers, but the district court dismissed their plea saying that there is no health hazard up to 100 mSV and relocation stress is greater than radiation. The main scientific base from the city government side on this trial was provided by Dr. Keiichi Nakagawa, Tokyo University Hospital Radiology associate professor, who wrote a book called “Truth about Radiation Exposure and Oncogenesis” in which he stated an amazing theory, “There will be NO increase of cancer patients in Fukushima.” As there are many doubtful statements in his book, so I sent more than 100 questions to him, but there has been reply from him yet.”
As special rapporteur of UN Human Rights Coucil had described, there are numerous amount of books and thesis that show health hazards under 100 mSV, but Japanese scholars, doctors, administration and judicature are purposely ignoring these scientific data.
Children’s relocation issue must be the of the paramount importance as of now. In fact, there has been increase among children’s death in Fukushima. The director of Fukushima Network for Saving Children from Radiation, Mr. Seiichi Nakate, found out that the numbeばんだ of minors’ death in Fukushima went up 1.5 times compared to the year before the accident based on the government dynamic statistics of population13. Especially, heart disease went up by double and increases were observed in cancer, leukemia, infectious disease, and pneumonia.
Even as for adults, according to acting director of Dr. Toshiyuki Ishihara, Ohara Medical Center, Fukushima city, heart diseases have been increased significantly after the accident. Prior to the accident in 2010, there were 143 heart failures and 266 heart strokes, but in 1st half of 2012, there were already 184 heart failures and 212 heart strokes in only 6 months period.
Even the state and municipal government acknowledged that the number of death is increasing in quake-hit areas, and the government Reconstruction Agency announced the establishment of a project team for examination and countermeasures on death related to the disaster. However, among the causes listed in this project, cesium influence on heart is excluded for examination though the stress-causing heart failure is included.
In December 2012, I heard that 2 brothers in Fukushima became acute leukemia at the same timing. Brothers would have inhaled the same air and eaten the same food, and there is a possibility that simultaneous acute leukemia could have been caused by radiation for these brothers. I made a phone call to Fukushima Prefectural Medical Society in December 2012 and I was astounded when I was told, “There have been no health damage observed in relation with radiation in Fukushima.” Even at this stage, official position on radiation related health damage is totally “a denial.” I stressed that they should tackle this issue more promptly since the situation could become too late especially for children in contaminated areas
In fact, the silence among Japanese doctors on radiation exposure issue is beyond imagination. I made another phone call to the Japan Medical Association, and their answer was, “We have not determined our position regarding this issue. We will make announcement on this in March 2014.” How relaxed they are! I repeated the acute leukemia story in Fukushima to them too, stressing the need to immediately tackle this issue.
As a matter of fact, I asked for this to the Medical Association, but I have no expectation from them. Because, after the nuclear accident, amazingly, the government decided to stop tracking the statistics of leukemia patient number in Fukushima and south of Miyagi, where the radiation exposure was the highest! What on earth can this be justified? I would like this fact to be known to the world.
This kind of failure to act is widely observed among layer of medical society. For example, in a mailing list with members of pediatricians, obstetricians and para-medicals, one member told me that some Fukushima pediatrician strongly denies any health hazards by radiation in Fukushima and controls the opinions of the mailing list telling concerned members not to listen to some activists and journalists. She told me my name was listed among others. I recently had some argument with a pediatrician practicing in a hot spot area. He was not concerned about children’s health at all.
It is a matter of grave concern that doctors, who are supposed to protect children’s health, have been behaving like this. It is not only a concern, already a calamity is started to be emerged.
Considering these things, children in Fukushima should be relocated at the earliest possible timing, but in the contrary, the government and Fukushima prefecture is to terminate the subsidiary for volunteer evacuees the end of this year and furthermore, the government has declared to let all the Fukushima residents back to their hometown by 2020. This is solely an insane policy.
Furthermore, Ministry of Economy, Trade and Industry allocated a large amount of budget to constructor extend state of the art medical facilities in Fukushima. Amazingly, the summary of the plan states that it aims at positive economic effect of 120 billion yen! http://www.jice.or.jp/sinsai/sinsai_detail.php?id=2485
It is totally inappropriate to build large sized hospitals in these contaminated areas. Immediately after March 11, dozens of in-hospital patients died while being evacuated. There may still be possibilities of further catastrophic accident in Fukushima.
Also, especially those who are sick, challenged and aged people who need care could be vulnerable to low level radiation, so they should be entitled to obtain medical treatment in uncontaminated area. Fukushima prefectural medical circle is tied with ETHOS project and the executive director of Fukushima Prefectural Medical Association Nobuo Tanji was giving lecture for ETHOS. Once again, those who are socially weak including children and pregnant women are not supposed to stay in contaminated areas. I call for immediate relocation of these people.
Not only that, since there are some hot spots in Tokyo and other prefectures equivalent to optional relocation spots, I sincerely hope children and pregnant women would be able to be relocated as an established system
While the Japanese government involves doctors in ETHOS project to keep Fukushima residents for studying low-level radiation effects and further, discard the statistics of leukemia patients, and construct cancer hospitals for future economic effects, I think it is an urgent matter for Fukushima residents, especially for children to be able to relocate through international organizations support as soon as possible.
end quote, by by Japanese journalist, Mari Takenouchi