Progress on Offsite Cleanup
Efforts in Japan
Takeshi SEKIYA
Ministry of the Environment, JapanSide Event by Government of Japan
at 56th IAEA General Conference, Sep 17, 2012
1

Radioactive Pollution caused by the accident at
Fukushima Dai-ichi NPP

250km
2

1

Framework of Decontamination
New legislation for promoting decontamination
The Act on Special Measures Concerning the Handling of Radioactive
Pollution came into force on January 1, 2012.
Based on this Act the followings are carried out:
- Planning and implementation of decontamination work- Collection, transfer, temporary storage, and final disposal
Special Decontamination Area
11 municipalities in (former) restricted zone or planned evacuation zone(<20km from the NPP, or annual cumulative dose is >20mSv )Decontamination is implemented by the national government(*) Entire area of Naraha, Tomioka, Okuma, Futaba, Namie, Katsurao, and Iitate.
Some area of Tamura, Minami Soma, Kawamata, and Kawachi.

Intensive Contamination Survey Area
104 municipalities in 8 prefectures (*), in which over 0.23 mSv/hour of air
dose rate (equivalent to over 1 mSv/Year) is observed, were designated.
Decontamination is implemented by each municipality. The national
government will take financial and technical measures.
(*) Iwate, Miyagi, Fukushima, Ibaraki, Tochigi, Gunma, Saitama, and Chiba

3Special Decontamination Area andIntensive Contamination Survey Area
Iwate

Miyagi

Fukushima

Gunma

Fukushima
NPP1Tochigi

Saitama

Ibaraki

Chiba

2

Basic Principles under the Act

Targets of the Decontamination
Additional * exposures over 20mSv/y- Aim at stepwise and rapid reduction of those areas based on the ICRP
Recommendation (2007).
* ‘additional’ means beyond natural background and medical exposure
Additional exposures < 20mSv/y- As a long term goal, aim at reducing to 1 mSv/y or less
GeneralPublicChildren

Reduce estimated annual exposure of the generalpublic by 50 % in 2 years (by Aug 2013)by radioactive decay, decay by natural factors and by decontamination- Reduce estimated annual exposure of children by 60 %in 2 years (by Aug 2013) by thorough decontamination of
their living environment.
by radioactive decay, decay by natural factors and by decontamination- The goals will be reviewed periodically

5Guidelines-Helping understanding regulations under the Act– Waste-related guidelines: storage,
maintenance and management standards anddisposal standards– Decontamination-related guidelines: methods
for the investigation and measurement of thestatus of pollution, decontamination and othermeasures, collection, transfer and storage ofthe removed soil
– Guidelines for decontamination workers:
exposure dose management methods,
preventive measures against internal exposure,safety and health management systems
63

IAEA International Mission on Remediation
The IAEA organized a fact-finding Mission to support the remediationon 7-15 October, 2011.
Highlight of Progress- Legal, economic and technological resources allocated- Arrangement to coordinate and share information with relevant organization- Use of demonstration sites to test and assess various remediation methods- Impressive monitoring and mapping effort , etc.
AdviceBalance, Justification, Optimization
Strengthening Coordination of the National and Local Government
Stakeholders Involvement
Sv rather than Bq/m2or m3
Utilize existing Waste Infrastructure
Analyze the benefit in reducing Doses
Cooperate between National and Local Government for Waste facilities, etc.
(Source: Final Report of the International Mission on Remediation of Large Contaminated Areas Off-site theFukushima Daiichi NPP, IAEA)

Progressin Special Decontamination Area

84Decontamination Policy for Special Decontamination Area
Policy in FY 2012 and 2013

Decontamination should be implemented taking into accountthe level of air dose rate.
Area less than 20mSv/year： Aiming for reducing additional
exposure dose less than 1mSv/year as long-term goal.
Area from 20～50mSv/year： Aiming for reducing exposure
dose in residential and farmland area less than 20mSv/year by
the end of FY 2013.
Area more than 50mSv/year： Demonstration projects will beimplemented. Lessons learnt will be reflected into futuredecontamination policy.
Policy After FY 2014
Aiming for reducing additional exposure dose less than 1mSv/Y as long-term
goal
Check and evaluate two-year decontamination results, consider proper
actions, and revise implementation plans as needed.

9

Progress of work in the Special Decontamination Area
Advance
Identification
Full scale
Securing
Decontamination
Decontamination of owners ofDecontamination temporaryplan(base facilities, etc.) houses, etc.
Works
storage sites

in operation

Tamura city

（Apr 13）

Narahatown
Kawauchivillage
Iitatevillage
Minami-Soma
city
Katsuraovillage
Kawamata
town

inpreparation
In（Apr 13） preparationin（May 24） preparation（June 25）

（Apr 13）（Apr 18）

local coordination
process

local coordination
process（Aug 10）

local coordination
processNamie town

local coordination
process

local coordination
process

Ookuma town

local coordination
process

local coordination
process

Tomioka town

local coordination
processlocal coordination
process

Futaba town

*Decontamination works in a municipality are to be implemented on the premises of formulation of
the decontamination implementation plan and securing of temporary storage sites.
105

Flowchart of actions in the decontamination process
Completion of thedecontamination(monitoring continues)

Confirmation ofdecontamination
methods and consent towork

Monitoring radiationlevels after thedecontamination

Decontamination
operations

Decision of thedecontamination
methods

Monitoring the radiationlevels and checking thecondition of the buildings(field surveys)

Meetings to explain
the results of fieldsurveys to theresidents

Identification of thestakeholders of the landConsent to accessto land, building,etc.

Reporting of theresults

Consultation with landowners and other stakeholders

Decontamination situation in the Special Decontamination area

In addition the Government commissioned Decontamination Model Projects to JAEA in FY 2011.
126

Decontamination Activities by Self-Defense Force・Operation completed on Dec. 19

Iiｔate Village Office

Average air dose rate

(1m, µSv/h)【asphalt】
2.94 @1.96（33% decreased）【Lawn】
4.39 → 0.96(78% decreased)※promulgated on Dec. 22 by the
Ministry of the Environment

Measurement after cleaning ditches

Thorough removal of soil on asphalt surface

Namie Village Office・Operation completed on Dec. 15

側溝の汚泥除去Average air dose rate
(1m, μSv/h)【asphalt】

0.50 → 0.33(34% decreased)【Stone pavement】

0.53 → 0.39(26% decreased)）
Cleaning ditches

Cleaning stone pavement※Promulgated on Dec. 22 by the
Ministry of the Environment

Decontamination Activities by Model Projects (Example1)〈Residential land〉
roof：water cleaning,cleaning with brush

Concrete floor：
High-pressure
water cleaning

wall：wiping

Concrete floor：
Shot blast

Gutter (vertical)：high-pressure
water cleaning

Concrete floor：
Surface grinding
machineGarden：removalof topsoil

Reference: Decontamination model project (JAEA)

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Decontamination Activities by Model Projects (Example2)〈Roadside tree〉〈Street Surface〉
High-pressure water cleaning by vehicle forrecovering functions of water drainage pavement

Cleaning of trunk(with water and brush)

Surface grinding by shot blast

Removal of topsoil

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Reference: Decontamination model project (JAEA)

Decontamination Model Work in the Joban Expressway■Objective
To test and evaluate various decontamination
methods taking into account different roadpaving conditions and air dose rates.
Zone Ⅱ■Outline
Zone Ⅰ
Period: March -July, 2012
Results:
Zone ⅢIn Zone I (most highly contaminated zone) it isconfirmed that air dose rate could be reduced
to less than 9.5 μSv/h, or equiv. to 50 mSv/y.
In zone II and III, it is confirmed that air dose rate
could be reduced to approximate 3.8μSv/h , or equiv. to 20 mSv/y.
Decontamination Zone

Air dose rate

Zone I

More than 9.5μSv/h(equivalent to morethan 50mSv/y )Zone II
Zone III

3.8～9.5μSv/h(Annually equivalentto 20～50mSv）

Situation
before theaccident

Cutting interval

Bridge interval
Cutting interval
Landfill interval

OpenedUnder
Construction

In-servicezone

Air dose rate at the center of expressway (µSv/h)Road shape

Landfill interval

Under
Construction

Situation
before the accident

Cutting interval

Before→After

Decreasing
rate

43.1
11.6
10.3
5.8
5.4
5.1

→→→→→→

8.3
4.2
5.92.32.54.1

▲81%
▲64%
▲43%
▲60%
▲54%
▲20%8Progressin Intensive Contamination Survey
Area17Decontamination Progressin Intensive Contamination Survey Area

78 out of 104 municipalities finalized their decontamination
implementation under the Act ( as of Aug 10, 2012 )<Example of Fukushima City>
Planning term : 5 years until Sep. 2016 ( 2 years as an intensive term)
Priority: Houses in high air dose areas, public facilities, especially forchildren.

＜Progress as of June 4 ＞

FY2011

Onami Area
Watari Area

391 houses

132 houses6,300 housesAll areas( over 0.23μSv/ｈ）

Low air dose Area
Orchards

Fruitstrees,Farmland,Orchards, grassfarm, etc.

Completed in Orchard：
2,000ha（100%）

General living area

Forestry
Public Facility

completed in357 houses ( 6%)18,700 . 29,000
houses houses

High air dose Area

Farm land

Completed in 418
houses（100%）

27houses

All the elementary& junior highschools

Hot spot: Decontamination completed

School routes, Ditches, Parks, Branch offices
and Public facilities, etc.
Decontaminate spots with high air dosenotwithstanding the area

Completed in 206
schools and nurseries（100%）

Reference: Fukushima Furusato Decontamination Implementation Plan

189

Efforts to secure Interim StorageFacility

19Efforts to secure Interim Storage Facility
Oct., 2011 Ministry of the Environment officially announced and explained theBasic Principles for Interim Storage Facility (the roadmap) to theheads of relevant municipalities
Main Contents• The National Government shall secure, maintain and manage the facility• The National Government shall make utmost efforts to start operationof the facility by January 2015. Location sites would be selected withinFY 2012
• Target materials for storage is limited to soil and waste generated inFukushima pref.
• Final disposal will be carried out outside Fukushima Pref. within about
30 years from the start of the interim storage.
Dec., 2011 The Ministry requested 8 towns in Futaba County and Fukushima
Pref. to examine location sites in Futaba county
Mar., 2012 The Ministry explained the 8 towns and Fukushima Pref. that thefacilities may be located separately in 3 towns ( Futaba, Okuma and Naraha)Aug., 2012 The Ministry proposed the sites for investigation to 8 towns andFukushima Pref.
2010Overview of the Interim Storage Facility
Installation &segregation facility
Public information
centerresearch
facility

Administrativebuilding
storagefacility

Volumereduction
facility

Landscaping & green bufferzone, etc.
Volume reduction
facilitystoragefacility

Administrat
ive building

Installation &segregation facility

Landscaping & green bufferzone, etc.
Research facility for decontamination &waste disposal（Before the storage)※ This picture illustrates envisaged facilities and structures at this moment,
and is subject to change in the future.

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Tackling the Challenges

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11

Tackling the Challenges

1. Seeking for more efficient/effective technology fordecontamination from the perspective of cost, time, etc.
through demonstration project and R&D (incl. Soil/ Waste
minimization and volume reduction)
2. Promotion of Public communication for securing
temporary storage sites, interim storage facilities, etc.
3. Research on the behavior and environmental fate ofCesium, including the development of transport models

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