Activity Report of TENORM Task Group

4. Present status on TENORM in Japan
4.1 TENORM Utilization in Japan8)
The UNSCEAR 2000 report described the minerals containing NORM and those activities
and concentrations. RP-122 also referred to the case where the percentage of the contents ofuranium and thorium in the residues or by-products could unintentionally increase through theprocess of the extraction of useful materials from certain minerals. Furthermore, these minerals
are chemically and physically processed and often occur in our living environment as consumer
products. For these reasons, on site dose rate measurement and activity concentration analysis as
to the industrial application of typical minerals and other materials and some consumer products
containing NORM were performed to prepare basic information for developing exemption
policies by the Nuclear Safety Division (Office of Nuclear Reactor Regulation and Office ofRadiation Regulation) of MEXT.
4.1.1 Industrial Application
The investigation was conducted for monazite, phosphate ore, titanium minerals,
bastnasite and zircon as the materials which may contain NORM with relatively highconcentration, and coal as the material which is massively imported and which volume reduction
is expected through the operation.
The results of analysis were summarized in Table 3. The BSS exemption levels of 232Th
and 238U series are 1Bq/g. If we use 1Bq/g as provisional reference criteria for activity
concentrations of minerals in raw materials, monazite, phosphate ore, zircon and bastnasite exceed
the reference criteria. The phosphate ores only from Jordan and Morocco exceeded the criteria.
This reveals that activity concentrations of the minerals vary with the producing countries.
It was found that the dose rate at 1m from the material reaches to several µSv/hr in several
cases, due to the adhesion of scales or accumulation of sludge in the operation process. However,in consideration of working time, the annual dose of workers is estimated to be about 0.40mSv at
most for the work at a bastnasite product yard. When workers handle raw material powders andother powdery substances, the amount of dust inhaled by the workers are estimated to be small
because of they usually wear dust protective masks.

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Table 3

Survey Results of Actual State of Application of Minerals including Uranium and Thorium

Phosphate ore

Monazite

Nuclide analysis *4concentratoin (Bq/g)
Annual imports
Products
Process(producing(by-products
238
232
MineralU
Th
Samplecountries))
Tens of tons in the Spa bathing Sandy monazite is pulverized
past(Vietnam, element, paint to use raw materials for health
About
Malaysia)
products, paint and spa bathing Monazite
About 40300*6elements.
About 0.9 million Diammonium Phosphate ore is decomposed
Phosphate ore (Jordan)
tons(China, Hydrogenwith the addition of sulfuric
Morocco, Jordan, phosphateacid into phosphoric acid andSouth Africa, etc.) (gypsum/
gypsum.
Diammonium Phosphate ore (Morocco)
fluorite/ soda hydrogen
phosphateissilicofluoride) produced by having this Phosphate ore (China)
phosphoric acid react withammonium.
Enriched phosphate

0.74
1.2
0.10
0.8

Titanium

Diammonium hydrogen phosphate
About 400,000 tons Titanium(SouthAfrica, oxide
India,
Vietnam, (Gypsum/
Australia, Canada, Iron oxide)
etc.)

TitaniummineralisTitanium mineraldecomposed with the addition(South Africa)of sulfuric acid, and titaniumoxide is then produced after
still standing, filtering, baking Titanium oxide products
and drying processes.

0.73
0.074- 0.44
0.018

Industrial waste

Bastnaesite

About 2,000-3,000 Abrasive
tons (USA)0.21

Bastnaesite is crushed with awet comminutor, and abrasives Bastnaesite raw materials
are produced after filtering,
drying, roasting, crushing andSolid separated through a filterclassifying processes

1.1
1.0

ZirconAbrasive products
About 70,000 tons Refractory(SouthAfrica,Australia, etc.)

1.4

Zirconisweighedandfirebricks are then produced Raw material (zircon sand)after mixing, molding, drying
and baking processes.
Firebricks (zircon 100%)

4.2
3.5

Dust collected at waste provisional
storage yard

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0.17

radiation dose rate *5 (µSv/h)Monazite warehouse
Surface: 100 (Th concentration 7%)
Product fabrication place
1 m: 0.8

Phosphate ore warehouse
Surface: 0.32-0.46
1 m: 0.19-0.22
0.0084 Phosphate ore storage
Floor surface: 0.26
0.00191m: 0.17
Phosphate ore (Morocco)
Surface: 4.6
0.0038
Product warehouse
Surface: 0.05
0.00441m: 0.05
Raw material minerals yard (South Africa)
0.13- 0.16
Surface: 0.20-0.40
1 m: 0.15-0.25
Still standing tank
0.0013
Surface: 0.30
1 m: 0.15
Industrial waste yard
0.23
Surface: 0.30
1 m: 0.15
Raw material yard
5.8
Surface: 1.9
1 m: 0.6
Raw material input hopper
4.9
Surface: 2.0
1 m: 0.10
Product yard
7.1
Surface: 3.6
1 m: 0.88
Raw material yard (zircon flour for firebricks)
0.77
Surface: 2.7
1 m: 1.0
80 % zircon-content refractor
0.81
Surface: 1.8
1 m: 1.2
Waste temporary storage yard
0.037
1 m: 0.15
0.0078Estimated effective dose(mSv/y)0.3 (work at product fabrication
place)(Annual working time: About 360
hours, workplace dose rate*7: 0.75
µSv/h)
0.28.
(Work
at
phosphateore
warehouse)(Annual working time: About 1,600
hours, workplace radiation rose
rate*7: 0.18 µSv/h)

0.27(work at minerals yard)(Annual working time: About 1,400
hours, workplace radiation dose
rate*7: 0.19 µSv/h)

0.40 (Work at product yard)(Annual working time: About 480
hours, workplace radiation dose
rate*7: 0.84 µSv/h)

0.14 (Work at product yard)(Annual working time: About 120
hours, workplace radiation dose
rate*7: 1.13 µSv/h)Activity Report of TENORM Task Group

About 155 million Fly
tons(Australia, clinker
China, Indonesia,
Canada, etc.)

ash When burning coal in a boiler,
clinkers and fly ash are Coal (China)
collected from the bottom of
the boiler and from a dust
Clinkercollector, respectively.

Coal

Coal-storage yard
0.13 (work at clinker warehouse)
Surface: 0.03
(Annual working time: About 1,100
1: 0.03
hours, workplace radiation dose
Clinker warehouse
rate*7: 0.12 µSv/h)
0.097
0.072
Surface: 0.15
1 m: 0.15
Ash disposal
Fly ash0.095
0.091
Surface: 0.15
1 m: 0.10(Surveyed by the Nuclear Safety Technology Center and other organizations in fiscal 2003)*4: The representative concentrations in the sample found in a mineral-by-mineral survey to have relatively high activity concentrations are shown. (2003 Survey by the Office of Nuclear Reactor Regulation, Nuclear Safety
Division, Ministry of Education, Culture, Sports, Science and Technology).
*5: The representative dose rates at the points found in a mineral-by-mineral survey to give relatively high dose rates are shown. The figure of 1 m means that the dose rate was measured at a point of 1 m away from a target
substance.
*6: The materials are subject to regulation due to that their thorium concentration and quantity exceeds 370 Bq/g and 900 g, respectively.
*7: The dose rate determined by subtracting a background dose rate (measured at a site boundary) from an ambient radiation dose rate at 1 m from a target substance.
0.015- 15 -

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Activity Report of TENORM Task Group

4.1.2

Consumer Products

NORM-containing minerals are chemically or physically processed and often used inliving environment as consumer products. Table 4 shows several examples of consumer
products containing NORM with the results of analysis on activity concentrations.
Table 4

Activity Concentrations in Typical Consumer Products
Analysis results (activity
concentration): (Bq/g)
238
232
U
Th

SampleRadon spa bathing element A

34

270

Ship bottom paint pigment

1281

Radon spa bathing element B

10

81

Bracelet/necklace (ceramics)

1.7-8.8

12-71

5.4

34

2.9-3.5

0.49-0.57

Muffler catalyst

3.3

210

Clothes (incorporating NORM in fabrics)
Supporter/wristband (incorporating NORM in
fabrics)
Odor-eating paint1

8.8

0.011-0.94

0.093-8.5

0.4-0.82

2.9-5.5

Socks (incorporating NORM in fabrics)

0.7

6.2

Seat (incorporating NORM in fabrics)

0.67

5.4

Shoe socking (containing powders)

0.085-0.42

0.63-6.2

Bedclothes (incorporating NORM in fabrics)

0.043-0.26

0.01-2.3

0.2

0.7

Phosphate fertilizer

0.038-0.073

0.0014-0.0015

Sinter or mineral encrustations left by hot springs

0.00084-0.012

0.00081-0.029

Health appliances (containing powders)
Refractory fire brickAbrasive(Surveyed by the Nuclear Safety Technology Center and other organizations in fiscal 2002)

They are utilized for various purposes ranging from the products with which only few
people could come in contact such as pigment for painting the bottom of ships and catalyst
applied to automobile mufflers to those which people could touch easily such as clothingmaterials and bedclothes.
As the results of the analysis, some consumer products were found to exceed the BSS- 16 -

Activity Report of TENORM Task Group

exemption level. An external dose represented 110 µSv/y for a radon spa-bathing element,
220 µSv/y for underclothes, 90 µSv/y for bedding clothes (futon), 10 µSv/y for wallpaper.
Therefore, the external dose of a person using these consumer products may neither exceed
nor reach to 1 mSv/y.

4.2

Japanese Regulation on TENORMTENORM containing natural nuclides which activity concentration is less than 370
Bq/g is not subject to practical regulation in the current Japanese legislative system. In theprocess of introduction of the concepts provided in ICRP publication 60 into the Japaneselegislative system, the Radiation Council had its General Administrative Group launch toreview incorporation of the international basic safety standards of IAEA (BSS) to thelegislative system and regulations since April 1999. It submitted the report on “Exemption” to
the Radiation Council in October 20029), noting that “exemption of NORM needs to bereviewed in the future based on investigation of their actual use in Japan and international
developments.” The Radiation Council decided in February 2003 that exemption of NORM
would be reviewed by the General Administrative Group. After discussions in the nine
meetings, the Group submitted the report in October 20038).
The report describes the results of investigation on status of actual use of NORM in
Japan. Various kinds of minerals, monazite, phosphate rock, titanium ore and etc. withradionuclides of Uranium and Thorium series and 147Sm were found to be widely used forindustrial purpose. The annual dose to workers handling these materials would not exceed
1 mSv/y. Ship bottom paint and various kinds of health promoting product such as apparatus
for artificial hot spring, clothes, bedclothes, etc. were used as consumer products in Japan.
The estimated dose of users due to these materials would not exceed 10 µSv/y under normal
conditions of use.
The Group discussed concept for future regulation of NORM in Japan. Use of NORM
would not be only related to “practice” but also subject to “intervention.” NORM out ofcontrol in essential (including radiation sources present in the environment such as soil and40
K in the body) should be “excluded” from the scope of regulation. NORM, extending fromthose with a very low level of radioactivity to those causing significant exposure, are broadly
distributed in the general environment and show extensively different ranges of radioactivity
concentration. Therefore, it is difficult to regulate them by establishing a uniform exemption
level of concentration. Various types of raw materials containing NORM are widely usedwithout awareness of their radioactivity. They would be considered to be existing sources,
which would be subject to intervention.
Taking into account these points of view, actual use of NORM should be classified byartificiality or possibility of actual exposure. Then adequate methods of regulation, exemption
or intervention exemption may be necessary to be determined in accordance with theircharacteristics based on the radiation dose. Approaches based on the radiation dose instead of- 17 -

Activity Report of TENORM Task Groupthe amount or the concentration should be established. Table 5 shows Classification of
NORM. Categories 1, 2 and 3 should be exempted from regulation. Categories 4, 5 and 6
should be newly subject to regulation. Categories 7 and 8 were excluded from considerationof exemption by the General Administrative Group this time.

Table 5Classification of and Proposed Approaches to Materials Containing NORM
Exclusion,
Practice orIntervention

Regulation by
Legislation
SystemApproaches

Dose Target/Criteria to Take
Approaches

1 Raw materials such as
mineral ore without
procedure of enhancing
concentration.
(except categories 2, 3,
4, 5 and 6).

Exclusion

Not regulated－－

2 Waste rock residues
from past mine orindustrial activities.

Intervention

Not regulated

Action level
will beconsidered

Examined in the
future(1-10 mSv/y)

3 Ash, scale, etc.
produced by industries(concentration ofsubstances treated as
raw materials should be
exemption level or
below)

Intervention

Not regulated

Action level
will beconsidered

Examined in the
future(1-10 mSv/y)Category (examples)

4.3

Some Events Related to TENORM

Some events related to TENORM were reported in these years. The examples of
those events were the waste from uranium mining and milling and titanium residue, thestorage of large amount of monazite ore, some consumer products using NORM (airpurification device, artificial radon spa) etc. Almost all events were taken up as a scandal by
the mass media even in the no illegal case. There could be pointed out the importance of (1)the provision of countermeasure corresponding to the situation and (2) the enlightenment andeducation of the general public on the knowledge of radiation.

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Activity Report of TENORM Task Group

4.3.1

NORM Waste from Uranium Mining and Milling Facility

A reclamation program on waste generated from uranium mining and milling at the
Ningyo-toge, Okayama, Japan is being conducted (Fig.3). Related wastes are mainlycomposed of uranium mill tailings and waste rocks left after a domestic exploitation projectfrom mid 50’s to late 80’s. Dismantling debris that will be generated from thedecommissioning of mining facilities is also expected (Table 6).

Fig.3

Locality of Ningyo-toge

Table 6 Major characteristic on waste
Waste

VolumeWaste Rock (17 sites)
Mill tailings
Heap Leaching Facility aTank, Valve, Ion Exchange
Resin, Concrete, etc

ca 200,000 m3
ca 34,000 m3
ca 10,000 drums(estimated)

Average U
Concentration (Bq/g)< 0.09 - 0.42
ca 3

Average 226Ra
Concentration (Bq/g)
ca 16

-

-

a) Demolition of heap leaching facility is now under consideration, therefore waste volume described here is based on
estimation.
Radionuclides contained in waste rock are considered to be uranium and its progeny, whereas mill tailings that is
residue of ore extracted by sulfuric acid, is depleted in uranium only (relatively rich in 226Ra).

Currently, they are maintained for the purpose of environmental protection including
radiological and non-radiological hazard in accordance with the Mine Safety Law (MSL).
Regarding radiological hazard, management of these waste is currently controlled by the limitof 1 mSv/a at site boundaries under MSL, and would be also applied a policy regarding
exemption of NORM/TENORM formulated by the Radiation Council in 2003.
Radionuclides in the waste consist of uranium-series with long half-lives, and requirelong-term waste management. Measures will be principally carried out with encapsulation inaccordance with MSL which is similar to remediation measures on uranium mill tailings and- 19 -

Activity Report of TENORM Task Groupmining sites applied in several countries (Fig.4). The objectives of the site measures are;solids containment, control of radiation exposure, control of radon gas, control of liquids,
stability and integrity of site structures. Monitoring and surveillance will be carried out inevery phase of the reclamation in order to verify the efficiency of site measures. Managementof the site would be maintained under the institutional control.

Fig.4

Suppositional measures on uranium mill tailings

Concept of measures has been established with a perspective through safety analysis
after a series of discussion at boards consisting of specialists and experts from otherorganizations. Current phase is the stage to perform various field measurements,
laboratory-scale tests and demonstration-scale tests in order to collect data for safety analysis
and site designing including analysis to evaluate site stability.
A current topic of the program is on measures of waste rock in the Katamo site, one of
17 yards around the Ningyo-toge (Fig.5). Following a decision of the Supreme Court, it isrequired to displace waste rock from the yard, which was estimated about 3,000 m3 according
to an agreement between a local community and the Power Reactor and Nuclear Fuel
Development Corporation, former JNC, in 1990. Radioactivity of the waste rock is equivalent
to the part of higher than 0.3 µSv/h. Suppositional measures would be displacement anddisposal in an inclined shaft or a shaft with plugging. The site and methodology for disposal
does not come to an agreement with interested parties i.e. local communities and/or local
governments, and JNC due to difference of their opinions.

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Activity Report of TENORM Task Group

Fig.5

Waste rock yard with relatively high radioactivity
The lower right portion shows a hole left after illegal andcompelling displacement of waste rocks in a flexible
container by a citizen’s group

4.3.2

Storage of Large amount of Monazite Ore

The existence of the monazite ore was clarified in June, 2000 by the investigation of
the police in several places in the country starting with the fact that suspicious mails which
enclosed the powder of the monazite ore had been sent to the official residence etc.
Science and Technology Agency (STA, present MEXT) received the report from thepolice, investigated the situation of its storage on each site, confirmed safety, and guided theowner to manage it appropriately.
The surface dose rates of the container and the door in the building in which themonazite ore was put were several tens µSv/h at the maximum, and some of the monazite ore
contained the thorium weighing more than 100kg, which needed the written report of use as
the nuclear source material.
The whole picture of the monazite and the intention of the use by the owner was
confirmed by the investigation, and the written report of the use of the monazite ore in twoplaces as the nuclear source material was performed.
In response to the above-mentioned problem, STA reported on "Appropriate
management of the radioactive materials" including the following contents at the end of 2000.
- The appropriate united system on the management of the nuclear source materials thataren’t used for energy with the management of other radioisotopes is to be examinedin the future from the viewpoint of the prevention from radiation hazard.
- The clarification of the exclusion and the exemption of the material with low doselevel from regulatory control is to be aimed at as maintenance of the standard
concerning the radioactive materials to be controlled based on the international
discussion.

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Activity Report of TENORM Task Group

References (for Chapter 2-4)
1)

ICRP Publication 60：1990 Recommendations of the International Commission on Radiation
Protection (adopted 1990), Annals of the ICRP, Vol.21, Nos.1-3 (1991).

2)

UNSCEAR：SOURCES AND EFFECTS OF IONIZING RADIATION, United Nations ScientificCommittee on the Effects of Atomic Radiation, UNSCEAR 2000 Report to the General Assembly,
with scientific annexes, (2000).

3)

IAEA: International Basic Safety Standards for Protection against Ionizing Radiation and for the
Safety of Radiation Sources, Safety Series No. 115 (1996).

4)

ICRP Publication 82：Protection of the Public in Situations of Prolonged Radiation Exposure,Annals of the ICRP, Vol.29, Nos.1-2 (1999).

5)

ICRP Publication 75：General Principles for the Radiation Protection of Workers, Annals of the
ICRP, Vol.27, No.1 (1997).

6) IAEA-RS-G-1.7：Application of the Concepts of Exclusion, Exemption and Clearance,
IAEA, Safety Standards Series No. RS-G-1.7, (2004).
7) The European Commission : Radiation Protection No. 122 Part II, “Practical use of the concepts
of clearance and exemption (Part II) - Application of the concepts of exemption and clearance tonatural radiation sources-“, (2002).
8)

Japanese radiation council: On the regulatory exemption of Natural Occurring Radioactive
Material, Report of Japanese radiation council, (2003). (In Japanese)

9) Japanese radiation council: On the regulatory exemption, Report of Japanese radiation council,(2002). (In Japanese)
10)

ICRP Publication 77：Radiological protection policy for the disposal of radioactive waste, Annalsof the ICRP, Vol. 27 supplement (1997).

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