Safety Regulations for Radioactive Waste Disposal Ⅲ

Overview and Activities of MEXT
February 23, 2010
Yoshinari AKENO
Director, Nuclear Safety Division
Science and Technology Policy Bureau１．Safety Regulations by MEXT
Usage of research & test reactors andnuclear material

Usage of radioisotopes and radiation
generating apparatus

校正用線源

Safety Regulation by the Law for theRegulation of Nuclear Source Material,
Nuclear Fuel Material and Reactors(The Reactor Regulation Law)

Safety Regulation by the Law Concerning
Prevention from Radiation Hazards due toRadioisotopes, etc.,(The Radiation Hazards Protection Law)12. Number of the licensed by MEXT and the State of Waste Storage
Under the Reactor Regulation Law
Type ofLicense

Research & TestReactors

Number ofLicensee

23（15 in operation）

Nuclear Fuel Material User

Nuclear Fuel Material User

(Governed by ordinance)(Not governed by ordinance)

Nuclear Source Material
User

194

17

15

As of January 8, 2010

Under the Radiation Hazards Protection Law
Type ofLicense
Number ofLicensee

Utilization
Approved
By MEXT

Notification
to MEXT

Certification
labels※

Total

2,476

567

2,714

5,757Sale265

Leasing

Disposal112

9Total6,143※The approved devices with certification labels
As of January 1, 20102

3-1. Regulations by the Law for the Regulations of Nuclear Source Material, Nuclear Fuel Materialand Reactors●MEXT regulates research and test reactors and installations using nuclear fuel materials
by the Law for the Regulations of Nuclear Source Material, Nuclear Fuel Material andReactors. Regulations for individual facilities are adapted to take into account the scale of
the reactor as well as the types and quantities of nuclear fuel material, which differ greatly
among facilities.
PlanningPlanning andandDesign
DesignResearch
Research &&Test
Test Reactors
Reactors

Usage
Usage ofof
Nuclear
Fuel
Nuclear Fuel
Material
Material

Construction
Construction

・Licensing for the reactor
installation (inc. NSCdouble check)・Approval for the design
and method ofconstruction and welding

・Inspection of welding
・Pre-service inspection

Licensing for usage

・Facility inspection (seenote 2)・Inspection of welding(see note 2)

OperationOperation(see note 1)
・Obligation of safety measures
・Approval of safety manual
・Safety inspection
・Periodical inspection of facilities
・Designation of the chief technician ofnuclear reactors
etc

・Obligation of safety measures
・Approval of safety manual (see note 2)
・Safety inspection (see note 2)
etc

Decommissioning
Decommissioning(see(see notenote 3)
3)・Approval for the planof decommissioning
・Confirmation ofcompletion ofdecommissioning
・Approval for the planof decommissioning
・Confirmation ofcompletion ofdecommissioning

Note 1: Specified nuclear fuel material users are imposed the obligation to safeguard nuclear fuel materials during the operation stage .
Note 2: Applies only to facilities handling quantities of nuclear fuel materials exceeding the level determined by ordinance no. 41
Note 3: Following the May 2005 revision to the Law for the Regulations on Nuclear Source Material, Nuclear Fuel Material and Reactors, the notification system became the permission system.

33-2. Clearance Regulation for JRR-3● In 2005 a clearance system was introduced under the Law for the Regulations of Nuclear Source Material, Nuclear Fuel
Material and Reactors. This system stipulates that waste generated from nuclear facilities, which emit lower levels of radiationeven compared to natural radiation, does not need to be treated as radioactive waste. Waste that has been confirmed by theregulatory bodies is governed by ordinances related to ordinary industrial waste and its recycling as valuable resources.
●Following the introduction of the clearance system, an application was submitted in 2007 for the approval of the method ofmeasurement and evaluation for the JRR-3, and it was approved in 2008. Following the evaluation by the nuclear licensee inaccordance with the approved method, a first application for confirmation was submitted in January 2010. The confirmation
process in MEXT is going on now.
Overview of clearance plan for JRR-3

Outline of the regulatory involvement related to clearance
Pre-evaluation（Establishment of measure ment and judgment
methods by nuclear licensee)

Step 1

Approval of measurement and judgment methodby regulatory bodies

Measurement and judgment for clearance by nuclear licensee

Step 2

Confirmation of measurement and judgment
results by regulatory bodies
Storage and management
Recording and quality assurance, etc

General plan
In the modification of JRR-3 of Nuclear Research Center, the Japan Atomic
Energy Agency (JAEA), concrete fragments of negligible radioactive level wasgenerated and stored now in waste storage facilities in JAEA.
JAEA plans to reuse the concrete as blast furnace slag at Nuclear ResearchCenter of JAEA if they have clearance from regulatory body, and plans to use
unoccupied area of current waste storage facilities for future disposal purpose.
Materials to be confirmed clearance●Generating facility Japan Research Reactor No.3 (JRR-3)（modified between 1985 and 1989)●Material Concrete fragments●FormFragments (from concrete), blocks●Volume Approx. 4,000 tons
●Storage: Waste storage facilities/NL pit inside Nuclear Science Research Institute, JAEA

43-3. Review of Clearance for Facilities Used Uranium● The Special Committee on Safety Radioactive Waste and Decommissioning of NSC
conducted investigations and deliberations aimed at establishing the clearance level ofmetallic radioactive waste derived through the conversion and enrichment of uranium
and fabrication of uranium fuel. They compiled a report in October 2009.
Evaluation result of clearance level in NSC report
Nuclides to be evaluatedevaluation result（Bq/g）

IAEA（RS-G-1.7）（Bq/g）

Ｕ－２３２０．２

０．１

Ｕ－２３４

１．５１Ｕ－２３５

１．４

１Ｕ－２３６

１．７

１０Ｕ－２３８

１．８１● To implement confirmation procedure in the clearance for uranium processing facilities
that use nuclear fuel materials, MEXT is currently deliberating on the establishment, etc.,
of clearance levels through the technical WG discussion of the Subcommittee on Safety
Regulations for Research Reactors. Completion of their report is scheduled in FY2009,
and amendments to ordinances are planned thereafter.
5４ｰ１． Regulations based on the Radiation Hazards Protection Law
Application

Notification of/approval for utilization of radioisotopes, etc., and radiation-generating apparatus
Notification of commercial sale/lease of radioisotopes, etc.
Approval of etc., disposal business of radioisotopes.
Approval by the Minister of Education,Culture, Sports, Science and Technology

Facility inspection ※Required compliance with facility standards

Adherence to utilization, etc., standards

Periodic inspection
Periodic verification ※※ objective facilities① Enterprises operating storage facilities ofradioisotopes exceeding a pre-determined level② Enterprises possessing radiation-generating
apparatus③Disposal enterprises

User’s Responsibility for Management① Appointment of Supervisor of Radiation Protection② Notification of internal rules for the prevention of radiation hazards③ Education/training of workers, etc., that utilize radioisotopes④ Health checks for workers who enter in controlled areas⑤ Measurement of radiation levels⑥ Records of utilization, storage, and disposal management⑦Submission of management reports⑧Periodic workshops/courses for the Supervisor of Radiation Protection

Inspection of premises

Decommission notification
Reporting measures associated with decommissioning

64-2. Consideration to establish the Clearance system in the Radiation Hazards Protection Law● Approx. 250,000※ radioactive waste materials will be regulated under the Radiation Hazards
Protection Law (as of March 31 in 2009; 200-liter drum equivalents). Approx. 50% of them are
low-level radiation materials even compared to natural radiation. Establishment of the clearance
system in the Radiation Hazards Protection Law contributes to the reduction of the cost of theradioactive waste disposal, and it facilitate reasonable usage of radioisotopes and radiation
generating apparatus in the research, industrial and medical fields.
Implementation
Implementation ofof thethe clearance
clearance systemsystemProper disposal○Measurem
ent ofradioactivity

Recycle○Evidence,etc., of decay

Concrete recycling

Confirmation of measurement and judgment results byregulatory bodies

Enterprises/operations

Measurement/evaluation in accordance with certified methods

Approval of measurement and judgment methodby regulatory bodies

Establish measuring and evaluation methods for clearance-eligible
objects/materials
Selection of candidates for clearance
Enterprises/operations

Buildings, walls, incinerated
ash, etc.

Metal-melting

Industrial waste,
general waste74-3. Background of the Review Process for Clearance Systems & Land Disposal
Clearance systems

1998Land Disposal (burial)

5-1998 Nuclear Commission Task Force on Nuclear Power Back-end Measures
On the Fundamental Outlook Regarding Research Centers & Waste Disposal① Fundamental Outlook on RI Waste Disposal Methods ② Estimate of RI Waste/Clearance Level Waste Volume, etc.
6-1998 Nuclear Safety Commission in Japan
Fundamental Outlook on Safety Regulations relating to the Disposal of Highly Radioactive Waste & Waste from RI Research Centers, etc. (deliberations commenced)
1-2004 (Nuclear Safety Commission in Japan)
Fundamental Outlook on Safety Regulations relating to the Shallow
Geological Disposal of Solid Radioactive Waste Generated at Facilities that
Utilize radioisotopes

8-2004 （IAEA）
RS-G-1.7 Application of the Concepts of Exclusion, Exemption andClearance
10-2004 （Subcommittee. on Safety Regulation for Radiation Protection in MEXT)
Commence deliberations on applying clearance systems to the Radiation Hazards
Protection Law
5-2005（Promulgated）
The Reactor Regulation Law(Implementation of clearance system, etc.)
6-2006 （Subcommittee. on Safety Regulation for Radiation Protection in MEXT)
The technical review regarding the establishment preparation of the clearance system
relating to the Radiation Hazards Protection Law (interim report)① Review of measuring/assessment methods for determining clearance of waste
generated in the dismantling, etc., of radiation-generating apparatus② Review methods for retaining the decay-storage-waste including only short-half-liferadionuclides

7-2009 （MEXT）
Fundamental policies for the system design of clearance system implementation, etc.
① System design must comply with the Reactor Regulation Law② Clearance assessment method (activation products, waste generated from utilizationof radioisotopes)③ Procedures for establishing clearance levels

20042005

2006

2008
2009

6-2004 (Promulgated)
Revision of the Radiation Hazards Protection Law (organization,etc., of stipulations to regulations relating to the land disposal)
9-2006 （Committee on R&D in the Field of Atomic Energy/Sub-working
Committee on Research and Evaluation/the Council on Science, Technologyand Academism in MEXT）“The approach to realize the disposal of radioisotopes and waste from researchfacilities etc.”(The Japan Atomic Energy Agency (JAEA) was designated as theimplementation entity of the disposal of low level radioactive wastes generated
at the facilities using radioisotopes and radiation generators and at otherlaboratories and research institutes.)
6-2008 （Promulgated）
Revision of the Law for the Independent Administrative Agency,
Japan Atomic Energy Agency （confer the status as the leadagency for the land disposal)

1-2010 （Subcommittee. on Safety Regulation for Radiation Protection in MEXT）“The result of technical Review to introduce the clearance system into the Radiation Hazards Protection
Law (2nd interim report)”8

Outline of “the result of technical Review to introduce the clearance system
into the Radiation Hazards Protection Law (2nd interim report)”(Subcommittee. on Safety Regulation for Radiation Protection & MEXT: compiled on January 2010.)【Content and result of technical review】
１．Calculation of the clearance level for contaminated materials with RI & activation products① Concept of calculating the clearance level
With regard to the main RI radionuclides in contaminated materials with RI & activation products, basically with the method used by NSC
to evaluate clearance level for nuclear reactor facilities, those radioactivity concentration (Bq/g) were evaluated, which were equivalent tothe value that the critical group will be exposed to dose rate of 0.01 mSv/y, when metal and combustibles (ashes/cinders) are disposed inland on recycled after their clearance.
② Calculation procedure of the clearance level
・ The amount of wastes which are assumed to be below the concentration shown in the IAEA Safety Guide, RS-G-1.7, were estimated basedon the result of investigation concerning the use of the radioisotopes and radiation generating apparatus in Japan.
・ Taking account of the result of investigation concerning the use of the radioisotopes and radiation generating apparatus in Japan, 53 and34 radionuclides were selected for calculating the clearance level for radioactive wastes and activation products respectively.
・ Evaluation routes, calculation models and evaluation parameters for the calculation of clearance level in the case of land disposal andrecycling of concrete and metal were selected on the basis of the method considered at the Nuclear Safety Commission of Japan. In thecase of land disposal and recycling of combustibles, recently they were also considered in the subcommittee.
③ Evaluated tentative values for the clearance level, comparison of the tentative values with the reference values for RS-G-1.7’s
exemption level on each radionuclide
・ The tentative values of the clearance level on 53 radionuclides for radioactive wastes and 34 radionuclides for activation products
were calculated by means of procedure described above.
・ The tentative values were compared with the reference values of IAEA.
・ As a result of above comparison, those tentative values were nearly same with the reference values in IAEA RS-G-1.7. Therefore, it wasconcluded that the IAEA RS-G-1.7’s exemption level can be adopted at the clearance level in the Radiation Hazards Protection Law.

9②Consideration on regulation of activation products produced by using the radiation generating apparatus
The concept of the regulation of activation products produced by the radiation generating apparatus (the linear accelerator forradiotherapy, and the medical compact cyclotron to produce radioisotope for the positron emission tomography) for medical use
was considered on the basis of the investigation result on the relationship between the maximum X-ray energy of the apparatus andthe occurrence of activation reactions in the parts installed in the apparatus.
ME of X-ray
ME ≦ 6MeV

6MeV＜ ME ≦10MeV

10MeV ＜ ME

The result of investigation on activation products
produced by using the linear accelerator
There was no activation products.

Future issues on activation products

Small amount of activation products in the target and in the ・To evaluate the threshold of the maximum X-ray energy
few parts around the target. These are regulated under the causing activation products in the target.
clearance system or managed as low-level radioactive
・To consider the categorization of the structure and component
waste.
without activation products except for target.
・To investigate activated area around the target.
Obviously activation products in the target and in the parts
・To categorize the concrete in radiotherapy room as thearound it.
component without activation products.

③ Methods for continuation of objective materials for clearance.
○ Evaluation methods used in the clearance procedure under the Reactor Regulation Law can be applied to the clearance
procedure for radioactive products produced by use of radiation generating apparatus.
○ The methods to evaluate the activity concentration of radioactive waste in the combustibles (ashes/cinders) was studied
on the basis of the methods used in the clearance procedure for nuclear reactors.
◎ Further investigation：+ Measurement of the concentration and evaluation of the unit, + Requirement of uniformity of concentration,+ Selection of representative radionuclides, + Response to mixture of radionuclides (e.g. nuclides difficulties of radiation
measurement, short half-life nuclide), + Clearance considering the decay of nuclides with short half-life.

104-3. General Administrative Group of the Radiation Council of Japan
Outline of “Basic Concept for Radiation Protection relating to Land Disposal of Solid
Radioactive Waste and Clearance (compiled on January 2010)”

１ Dose criteria for public exposure for optimization of radiation protection○ Dose limit for public exposure to radiation from burial ground of solid radioactive Waste→ 1ｍSv/year○ Dose constraint for public exposure to radiation from burial area of solid radioactive
waste after the period for active control.
→ an upper bound of 300 μSv/year
It is necessary to optimize of radiation protection for any dose that may affect the exposure tothe general public resulting from disposed waste after the period for active control at the stage ofplanning of disposal facilities.It is estimated that only few nuclear facilities may affect the exposure
to the general public .
It is appropriate that 300μSv/year for dose constraint to guarantee public exposure of less than
1mSv/year, by refering to refer to the standards of the International Commission on RadiologicalProtection (ICRP) .

11

4-3. General Administrative Group of the Radiation Council of Japan

２．Dose criteria for potential exposure by radioactive waste of long-lived radionuclide1）Dose criteria applicable to normal exposure situations in natural process
・Dose assessment is applied to a disaggregated dose/probability approach.
・Likely, or representative, release scenarios are identified and the evaluated doses
from these scenarios are compared with the dose constraint ( an upper bound of
300μSv/year).
2）Dose criterion that nearby population might be exposed through accidental human
intrusion into burial area in the future→ an upper bound of 20 mSv/year
３．Individual dose criterion for clearance→ 10μSv/year12