FY2014 Decontamination Report- A compilation of experiences to date on decontamination for the living
environment conducted by the Ministry of the Environment -(Tentative Translation)

March 2015

Ministry of the Environment

Tentative Translation< Attention >This material was translated temporarily and might be corrected in the
future.

Introduction
Radioactive materials were released by the accident at the Fukushima Daiichi
Nuclear Power Station (1FNPS) after being hit by the Great East Japan Earthquakeand ensuing Tsunami on March 11, 2011. The Government of Japan as well as
prefectural and municipal governments have been taking measures to decontaminate
the contaminated soil and wastes (hereinafter referred to as “decontamination”), in
order to reduce the impact of radioactive materials on human health and the living
environment as soon as possible.
In the efforts for the decontamination, all available resources including those fromthe central and local government offices, research institutions, and private cleaning
operators have been put together, along with the most recent scientific and technicalknowledge available from Japan and abroad. Of course it is the most important for theworld never to repeat such a disaster in the future. In the meantime, disclosing andsharing our knowledge, experiences, and lessons obtained through the decontamination
efforts at this time with domestic peers and the international community will besignificant to accelerate the decontamination work in Japan and minimize the potential
damage in future accidents in the world for the implementation of expeditious andefficient decontamination.
Therefore, in this Decontamination Report (hereinafter referred to as “the report”),
the Ministry of the Environment (MOE) has comprehensively compiled the basic policyof the decontamination and implementation framework, knowledge about the
management of decontamination projects based on the actual decontamination
operations on-site, together with the procedures, conditions and effects of individual
decontamination techniques, by mainly focusing on the decontamination operations
performed by the MOE. Thus, this report is deemed to be a fundamental document todisseminate both domestically and internationally our experiences, lessons andknowledge learned through the decontamination efforts.
The report consists of the following seven chapters:
1. Basic features of the environmental decontamination in Japan
2. Overview of decontamination methods
3. Management and treatment of decontamination wastes
4. Management of decontamination projects
5. Effects of decontamination
6. Overview, usage and conditions of decontamination technologies andverification of their effects
7. Conclusion
Chapter 1 describes the history and background of the demonstration projects, thecontamination status of decontaminated areas and features of the demonstration
projects. Chapter 2 outlines the process to establish decontamination procedures anddecontamination methods on the basis of the MOE’s document “Decontamination
Guidelines (2nd Ed., 2013)” Chapter 3 explains the management and treatment ofremoved soil and wastes derived from decontamination works with examples of
temporary storage sites, disposal and treatment of water used for decontamination
works and volume reduction for burnable wastes. Chapter 4 illustrates operation
planning for a large range of decontamination projects, including such example tasks asacquiring stakeholders’ consent, having effective communication with residents,
managing the projects and providing radiation protection, education and health care fordecontamination workers. Chapter 5 presents a wide range of area-wide
decontamination effects and their evaluation approach. Chapter 6 explainsdecontamination methods and their effects from a technical viewpoint on the basis ofdata obtained in test decontamination works in order to demonstrate findings on theeffects of individual decontamination technologies used in the full-scaledecontamination works. Chapter 7 summarizes the main points of the report.
It is the expectation of the MOE that this report will facilitate more effective andefficient decontamination works in the environmental remediation after the accident at
the 1FNPS, and contributes to preparations for potential nuclear accidents and related
research worldwide.

C o n t e n ts
1． Basic features of the environmental decontamination in Japan..................................1
1.1. History of the environmental decontamination .............................................................1
1.1.1. Specific features of the decontamination in Japan and Fukushima Prefecture...........1
1.1.2. History of the principal events associated with decontamination................................1
1.1.3. Overview of the change of the evacuation area designation.................................... 24
1.1.4. Outline of the Act on Special Measures Concerning the Handling of Environmental
Pollution by Radioactive Materials Discharged by the Nuclear Power Station Accident
Associated with the Tohoku District Off the Pacific Ocean Earthquake That Occurred
on 11 March 2011 .................................................................................................. 29
1.1.5. Overview of the Special Decontamination Area....................................................... 32
1.1.6. Overview of the demonstration model projects for decontamination ........................ 41
1.1.7. Outline of the Intensive Contamination Survey Area ............................................... 54
1.2. Features of contamination ..........................................................................................66
1.2.1. Dispersion status of radioactive materials ............................................................... 66
1.2.2. Major nuclides........................................................................................................ 69
1.3. Features of decontamination ......................................................................................73
1.3.1. Unprecedented large-scale decontamination activities............................................ 73
1.3.2. Decontamination to secure safety at an early stage and to facilitate restoration andreconstruction........................................................................................................ 76
1.3.3. Project operation with consideration of the maintenance of community and theprotection of rights ................................................................................................. 78
1.3.4. Careful response with consideration for residents’ position and feelings.................. 80
2．Overview of decontamination methods ..........................................................................81
2.1. Guidelines for Methods for Investigation and Measurement of the Status ofEnvironmental Pollution in the Intensive Contamination Survey Area .......................81
2.1.1. Basic Concept........................................................................................................ 81
2.1.2. Indicators of the Contamination Status by Radioactive Materials............................. 83
2.1.3. Methods for Investigation and Measurement to Determine the Areas to be Included ina Decontamination Plan......................................................................................... 85
2.1.4. Methods for Taking Detailed Measurements in Decontamination Zones .................. 87
2.1.5. Evaluation of Decontamination Results................................................................... 88
2.1.6. Measuring Devices and Methods of Use................................................................. 88
2.2. Guidelines Pertaining to Decontamination and Other Measures ...............................92
2.2.1. Basic Concept........................................................................................................ 92
2.2.2. Decontamination and Other Measures for Buildings and Other Structures .............. 93
2.2.3. Decontamination and Other Measures for Roads ................................................. 115
2.2.4. Decontamination and Other Measures for Soil...................................................... 125
2.2.5. Decontamination and Other Measures for Vegetation ........................................... 135
2.2.6. Decontamination Measures of Rivers and Ponds, etc. .......................................... 143
2.3. Guidelines Pertaining to the Collection and Transfer of the Removed Soil ............ 149
2.3.1. Basic Concept...................................................................................................... 149
2.3.2. Requirements for Collection and Transfer of the Removed Soil............................. 149
2.3.3. Specific Actions .................................................................................................... 149
2.4. Guidelines Pertaining to the Storage of Removed Soil ........................................... 152i2.4.1. Safety Measures and Requirements Necessary for Storage ................................. 152
2.4.2. Specific Examples of Storage Methods Chosen on the Basis of the
Facility/Management Requirements ..................................................................... 154

3． Management and treatment of decontamination wastes ......................................... 161
3.1. Temporary Storage Sites and Final Disposal .......................................................... 161
3.1.1. Waste Treatment Flow and Necessity of Temporary Storage Sites ........................ 161
3.1.2. Configurations of Temporary Storage Sites ........................................................... 163
3.1.3. Examples of Temporary Storage Sites .................................................................. 165
3.2. Wastewater Treatment ............................................................................................. 170
3.2.1. Notes of Caution for Wastewater Treatment ......................................................... 170
3.3. Volume Reduction .................................................................................................... 173
3.3.1. Necessity of Volume Reduction ............................................................................ 173
3.3.2. Volume Reduction Methods.................................................................................. 173
3.3.3. Examples of Volume Reduction............................................................................ 175
4． Management of decontamination projects ................................................................ 179
4.1. Flow of the Decontamination Process ..................................................................... 179
4.2. Contents of Decontamination Work ......................................................................... 180
4.2.1. Knowing the Air Dose Rates by Detailed Monitoring ............................................. 180
4.2.2. Decontamination Work Ordered by the Ordering Party (MOE) .............................. 183
4.2.3. Decontamination Work by Decontamination Business Operators .......................... 189
4.2.4. Securing of Necessary Resources by Decontamination Business Operators......... 205
4.3. Acquisition of Residents’ Consent ........................................................................... 215
4.3.1. Efforts Made by the Ordering Party (MOE) ........................................................... 215
4.3.2. Efforts Made by Decontamination Business Operators ......................................... 220
4.4. Communication with Local Residents and Local Municipalities .............................. 221
4.4.1. Securing Temporary Storage Sites ....................................................................... 221
4.4.2. Launching of the “Decontamination Dial 110 (Hotline)” to Receive Information about
Questionable Decontamination Work ................................................................... 221
4.4.3. Efforts Made by Decontamination Business Operators ......................................... 221
4.4.4. Provision of Wide-ranging Information to Local Residents, etc. ............................. 225
4.5. Project Management Executed by Decontamination Business Operators ............. 226
4.5.1. Schedule Control ................................................................................................. 226
4.5.2. Operational Framework for Decontamination Work............................................... 227
4.5.3. Sharing of Information and Safety Precautions ..................................................... 229
4.5.4. Hiring and Separation Management of Workers.................................................... 231
4.5.5. Protection from wildlife ......................................................................................... 231
4.6. Radiation Protection Measures ............................................................................... 232
4.6.1. Ionizing Radiation Ordinance for Decontamination ............................................... 232
4.6.2. Surface Contamination Inspection (Screening) ..................................................... 232
4.7. Education and Health Care for Decontamination Workers ..................................... 233
4.7.1. Education for Workers.......................................................................................... 233
4.7.2. Morale and Conscientiousness of Workers ........................................................... 240
4.7.3. Personal Exposure Dose Management for Workers.............................................. 241
4.7.4. Medical Checks for Ionizing Radiation and Use of Whole Body Counters ............. 242

ii

5． Effects of Decontamination ......................................................................................... 243
5.1. Evaluation Pertaining to the Goals of the Basic Policy ........................................... 243
5.1.1. Facilities Subject to Evaluation ............................................................................. 243
5.1.2. Basic Approach of Evaluation Methods................................................................. 244
5.1.3. Evaluation Methods and Results .......................................................................... 244
5.2. Overview on the Decontamination Effects............................................................... 246
5.2.1. Data for Evaluation............................................................................................... 247
5.2.2. Summary of the Results ....................................................................................... 247
5.3. Decontamination Effects in Five Areas: Public Facilities, Residential Areas, Roads,
Farmland and Forests ............................................................................................. 249
5.3.1. Public Facilities and the Like ................................................................................ 249
5.3.2. Residential Areas ................................................................................................. 250
5.3.3. Roads .................................................................................................................. 251
5.3.4. Farmland ............................................................................................................. 252
5.3.5. Forests................................................................................................................. 253
5.4. Effects at Each Target Decontamination Place ....................................................... 254
5.4.1. Outline ................................................................................................................. 255
5.4.2. Effectiveness of Decontamination Methods for Each Target Decontamination Place........................................................................................................................... 256
6． Outline of decontamination methods, applications and conditions thereof, andexamination of the effects ........................................................................................... 271
6.1. Outline of Decontamination Methods and Their Applications and Conditions ........ 271
6.1.1. Residential Areas, Schools, Parks, Large Facilities, Roads, etc. ........................... 274
6.1.2. Slopes ................................................................................................................. 334
6.1.3. Rice Fields, Dry Fields, Pastures, etc. .................................................................. 336
6.1.4. Grassland, Lawns ................................................................................................ 363
6.1.5. Forests................................................................................................................. 369
6.2. Verification of Decontamination Effects ................................................................... 382
6.2.1. Residing-restricted Areas (Areas in Which Residing is Restricted) or Evacuation
Orders Lifting Preparation Areas (Areas in Which Evacuation Orders Are Being
Prepared for Lifting) ............................................................................................. 383
6.2.2. Difficult-to-return Areas (Areas Where It Is Expected That the Residents Have
Difficulties in Returning for a Long Time) .............................................................. 398
7． Conclusion .................................................................................................................... 418

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1． Basic features of the environmental decontamination in JapanThe decontamination projects associated with the accident at the Fukushima Daiichi Nuclear Power
Station (1FNPS) of Tokyo Electric Power Co., Inc. (TEPCO) have the following basic features involving
the status of environmental pollution, geographical factors, and the stance of the national and the local
governments toward residents.
The principal radionuclide causing environmental pollution is cesium.
Decontamination should be conducted to reduce the impact on human health or the living
environment not only in housing areas and public facilities, but also in diverse and wide
areas including roads, farmlands, forests around the living space, and the like.
Decontamination should be implemented as soon as possible for early return, safety
protection and life rebuilding of residents in the evacuated areas.
Residents' opinions and their way of life should be respected; decontamination should be
conducted by paying due consideration to the protection of private rights and maintenanceof the community.

Hereinafter, the history and the background of decontamination, the status of theradioactive contamination, and features of decontamination works are given in the following
parts 1.1, 1.2 and 1.3, respectively, which led to the formation of the above characteristics.

1.1. History of the environmental decontamination
1.1.1. Specific features of the decontamination in Japan and Fukushima Prefecture
In Japan, about two-thirds of the country is occupied by forests, and the proportion of the inhabitableland areas limited to about the remaining one-third. Therefore, the population density in inhabitable land
tends to be high. In addition, as Japan is the only nation to have been hit by nuclear bombs, the Japanesepeople have a stronger interest and greater concern than the people of other countries toward the damage
caused by radiation. On the other hand, knowledge about radiation and its influence on the human health
had not been shared sufficiently among ordinary person, before the Great East Japan Earthquake.
In Fukushima Prefecture, which most strongly received the effects of the nuclear power plant accident,
the population in October 2010 was about 2 million people and the total area is approximately 14,000
square kilometers. While this is a vast land area, it is used in various forms. The utilization ratio of theland 1 is: forests, about 70 %; agricultural land, about 11%; the surface covered with water bodies, rivers
and waterways, about 3 %; and roads and residential land, about 4%. The east side of Fukushima Prefecture
faces the Pacific Ocean, and the west side is surrounded by mountains. Therefore the situation of the four
seasons is quite different between in the eastern and western regions of the prefecture. In 2014, Fukushima
City, located in the central region, had 96 snowfall days and the number of days was relatively large inJapan. Based on these specific circumstances in Japan and Fukushima Prefecture, most appropriate
decontamination activities are due to be carried out.

1.1.2. History of the principal events associated with decontamination（1） Occurrence of the accident at the nuclear power station and evacuation of residents
At 14:46 on March 11, 2011 (Japan time, hereinafter all times are this), an earthquake
occurred off the Pacific Coast of northeast Japan. The earthquake and ensuing tsunami
damaged facilities of the Fukushima Daiichi Nuclear Power Station (1FNPS) and the
Fukushima Daini Nuclear Power Station (2FNPS) of Tokyo Electric Power Co., Inc. (TEPCO),
setting the stage for an unprecedented complex nuclear accident that led to releases ofsubstantial amounts of radioactive materials to the atmosphere from the 1FNPS.
1Source: Fukushima Prefecture, "2014 edition, Recording of the main data in Fukushima Prefecture"(http://www.pref.fukushima.lg.jp/sec/11045b/26youran.html)

1Then Prime Minister Naoto Kan declared a nuclear emergency situation at 19:03 on March
11, 2011, and established the Nuclear Emergency Response Headquarters (NERH) within thePrime Minister's Office according to the Act on Special Measures Concerning Nuclear
Emergency Preparedness (Law No. 156, 1999).
In the meantime, the Fukushima Prefectural Government set up the prefectural
headquarters for disaster control. Upon receipt of the declaration of a nuclear emergency
situation at the 1FNPS, at 20:50 on March 11, 2011, the Governor of Fukushima ordered
Okuma and Futaba Towns to evacuate the residents living within the radius of 2 km from the
1FNPS.
At 21:23 on March 11, 2011, the NERH ordered the Fukushima Governor and otherrelevant authorities of the municipalities to evacuate the residents living within the radius of
3 km from the 1FNPS and to order those living within the radius of 10 km from the 1FNPS toremain indoors. Then, on March 12, 2011, the NERH ordered the Fukushima Governor andother relevant municipalities to evacuate all residents living within the radius of 20 km fromthe 1FNPS.
Later, following the hydrogen explosion at Unit 3 and others on March 14, the NERH on March 15, 2011,
ordered the Fukushima Governor and relevant authorities of the municipalities to instruct the residents
living in an area between the radius of 20 km and 30 km from the 1FNPS to remain indoors.
On March 17, 2011, the Ministry of Health, Labour and Welfare（MHLW） set the index values2 onfood and drink intake limit of radioactive materials as provisional regulation values of the Food Sanitation
Act, and began the radioactivity monitoring of foods3.
On March 19, 2011, radioactivity exceeding the provisional regulation values of radioactive materials infoods were detected in certain areas in spinach and raw milk, etc., and in response to this situation, theNERH summarized a "Monitoring plan, and a policy on setting and lifting of the food items and the areas
to be subjected to shipment restrictions, etc.". In addition, concerning the planting of rice which is a staple
grain food in the Japanese diet, the NERH presented on April 8, 2011, "The policy on planting of rice", andtook measures for foods, such as imposing planting restrictions on rice in places where the radioactivity ofthe produced rice was more likely to exceed the provisional regulation values4.
In addition, on April 21, 2011, the NERH announced to the Fukushima Governor and the mayors of otherrelated municipalities that it had designated the area located within the radius of 20 km from the 1FNPS as
the restricted area, in order to secure the complete safety of residents.
Some evacuees thought that the evacuation was a "temporary refuge of around several days" at the
beginning of the disaster occurrence. However, after about 1 month, concerns about the prolonged
evacuation life became tangible, and feelings of anger and anxiety spread among evacuees.

（2） Understanding the status of the environmental contamination based on monitoring dataand zoning of the evacuation areas
The monitoring data by the Ministry of Education, Culture, Sports, Science and Technology (MEXT)
showed areas with high accumulation of radioactive materials in the areas located beyond the radius of 20km from the 1FNPS. On April 22, 2011, the NERH announced to the mayors of local municipalities that it
had newly designated such areas located beyond the radius of 20 km from the 1FNPS as the deliberate
evacuation area. In addition, the area between the radius of 20 km and 30 km from the 1FNPS, formerly
designated as the sheltering area was designated as the “evacuation-prepared area in case of emergency,”
excluding the above “deliberate evacuation area.” The above designation requested the residents in the
deliberate evacuation area to schedule their departure from the area, and the residents in theevacuation-prepared area in case of emergency to prepare for evacuation or shelter indoors in case of
emergency. In addition, there were certain spots outside the deliberate evacuation area where substantial air
dose rates continued to be found and so the annually cumulative exposure dose one year after the accident
2Source: Ministry of Health, Labour and Welfare(MHLW),"Handling of radioactively contaminated food"(March 17, 2011)
3The provisional regulation values set on March 15, 2012 are not values established for the emergency
response after the accident, but are new values determined from the long-term perspective.
4Source: Ministry of Agriculture, Forestry and Fisheries (MAFF), “White Paper on Food, Agriculture andRural Areas: 2011" (April 24, 2012)2

was anticipated to exceed 20 mSv. On June 16, 2011, the NERH designated such locations as “specificspots recommended for evacuation,” by announcing the policy of raising awareness and supporting andpromoting the evacuation of residents5.
On August 3, 2011, the Ministry of Agriculture, Forestry and Fisheries (MAFF) published the "Basic
policy on investigation of radioactive materials in rice," and decided to investigate radioactive materials in
rice, a stable food in the Japanese diet, at two stages the “preliminary investigation" before harvesting thecrop and the "main investigation" after harvesting it 6. In addition, the MAFF carried out a survey of theradioactive contaminants that targeted a total of about 580 points in Fukushima Prefecture and fivesurrounding prefectures, and published a concentration distribution map of the radioactive materials inagricultural soil4.
On August 9, 2011, the NERH announced its concept for the review of the evacuation areas7.
The announcement stated the evacuation orders had substantial impacts on the lives ofresidents and it would be appropriate to review the orders, once the status changed because ofconfirming such as the verification of safety of nuclear reactor facilities and reduction of dose
rates through continued monitoring.
Even outside the evacuation area, contamination was found. Also, it became apparent that
evacuation had to be inevitably prolonged. Under this situation, some evacuees moved farther
from the 1FNPS. Some residents even in non-evacuation areas also moved away farther on
their own decision.
Residents were highly worried about the radioactive contamination of the living
environment. They proactively collected information about radioactive materials and thestatus of contamination by themselves because of limited availability of relevant information.
As a result, diverse information was circulated regardless of its quality via SNS and othermeans. In such a situation, prefectural, municipal, and community officials who needed todirectly communicate with residents made efforts to soothe the confusion between residents
by actively providing residents with the latest information and advice on radiation protection.
They had to so act, while responding to the disaster and confirming safety and location ofresidents, by referring to the information provided by the national and prefectural
governments and opinions of experts with whom they had personal contacts, They also lacked
sufficient information.
On September 30, 2011, MEXT announced the “Results of nuclide analyses of plutonium
and strontium”. These results showed that the effects of plutonium and strontium exposure
were much lower in comparison with that of cesium, confirming that the primary concern
should be cesium.
The total number of evacuees in the whole of Fukushima Prefecture was about 164,000 at its peak asshown in figure 1-1. The number of evacuees from the evacuation order areas reached 81,000 as of August
8, 2013. Considering that the population in Fukushima Prefecture as of October 2010 was about 2,000,000
as stated in 1.1.1, it can be understood how a lot of people evacuated.

5Source:

Nuclear Emergency Response Headquarters (NERH), “Addressing the specific spots where thecumulative exposure dose one year after the accident is expected to exceed 20 mSv” (June 16, 2011)
6 Furthermore, the concentration of radioactive cesium exceeding the provisional regulation values was
detected in rice from certain areas after the survey, so rice shipment restrictions were enforced in thoseareas.
7Source: Nuclear Emergency Response Headquarters(NERH), “Concept of the review of the evacuation areas”(August 9, 2011)3

Evacuees in whole Fukushima Prefecture
About 146,000 people

Evacuees from the evacuation order areas
About 81,000 people(11 municipalities)* approximately 164,000 at its peak(June, 2012)
Evacuation order lifting preparation area
About 33,000 people (41%)

Residence restricted area
About 23,000 people (29%)

Difficult-to-return area
About 25,000 people (31%)

Former emergency evacuation preparation area
About 21,000 million people

Hirono Town, Naraha Town,
Kawauchi Village, Tamura City,
Minamisoma City

* Approximately 28,000 people just before
lifting (September, 2011),

Other evacuees
About 44,000 people

The whole area in Fukushima
Prefecture including
Fukushima City,
Koriyama City, Iwaki City

(Remarks)
・The refugees from the whole Fukushima Prefecture are based on the damage information bulletin (Part 1031) (September 17, 2013) of the
Fukushima Prefecture “Tohoku – Pacific Ocean Earthquake, FY 2011”.
・The number of refugees from the evacuation order areas was totaled by the Assistance of Residents Affected by the Nuclear Incidents based on theinformation caught from municipalities (the number of resident registration as of August 8, 2013).
・The number of refugees from the former emergency evacuation preparation area was totaled by the Assistance of Residents Affected by the
Nuclear Incidents based on the information caught from municipalities (as of September 17, 2013).

Figure 1-1 The number of evacuees from the evacuation order areas8 .

（3） Implementation of emergency measures
1）Formulation of response policy
Upon discovery of radioactive contamination even outside the evacuation order areas,
emergency measures were also required there and various efforts were made accordingly.
Japan’s Act on Special Measures concerning Nuclear Emergency Preparedness stipulated that it was the
responsibility of the NERH to resonsd to the nuclear emergency and take post-accident measures in order toprevent the expansion of nuclear disaster and to promote the restoration activities. However, no practicallegal framework covering such points as specific methods and framework to address the release ofradioactive materials into the environment had been formulated before the accident occurred. Under thissituation, the Government immediately formulated and announced provisional policies such as criteria forthe treatment of disaster wastes9, criteria for radiation protection10, and dose criteria in schools to securechildren's living environment 11.
In addition, because radioactive materials which exceeded the provisional standard values prescribed in
the Food Sanitation Act were detected in tea leaves grown outside Fukushima Prefecture, the MAFF
stopped the shipment of those products and conducted investigations 12.

8Source: Cabinet Office, "Review of the evacuation instructions" (October 2013)

9Source: Ministry of the Environment (MOE), “Handling of disaster waste in Fukushima Prefecture for thetime being” (May 2, 2011)10Source: Nuclear Safety Commission, “The basic idea about radiation protection and decontamination” (May19, 2011)

11Source: Ministry of Education, Culture, Sports, Science and Technology (MEXT), “Tentative ideas in judging

the use of buildings and playgrounds of schools in Fukushima Prefecture” (April 19, 2011)12Source: Ministry of Agriculture, Forestry and Fisheries (MAFF), “White Paper on Food, Agriculture andRural Areas 2011" (April 24, 2012)42）Decontamination activities started by various entities
Since the contamination had expanded outside the evacuation order area, somemunicipalities started their own efforts to reduce radiation exposure. Initially, the emphasis
was placed on reduction of children's exposure to radiation.
The pioneers were Date City and Koriyama City. Date City started a demonstration test at
a school ground of former Shimooguni Elementary School from April 21, 201113. Koriyama
City began to remove topsoil of school grounds from April 27, 2011 14. In May 2011, a group of
experts on radiation from the Japan Atomic Energy Agency (JAEA), in cooperation with
Fukushima University, conducted the field survey to verify the reduction measures of air dosein schoolyards and kindergarten yards15 . As a result, two soil treatment methods were
presented: one was to collectively bury soil underground and the other was to verticallydisplace soil (upside-down plowing (deep plowing)). JAEA then continued monitoring theeffectiveness of the dose reduction activities at not only school grounds but also at school
swimming pools in municipalities. They also cooperated in the formulation of
decontamination guidelines based on their expert knowledge (In those days, the term
“decontamination” was not in common use; rather the term “dose reduction activity” wasused.)In addition, experts with knowledge of radiation played the role of decontamination
advisors for several municipalities such as Date City, Minamisoma City, and Iitate Village tostart decontamination activities (Figure 1-2 shows decontamination work in Date City).
Each municipality, whick lacked knowledge on radiation and sufficient personnel fordecontamination conducted dose reduction activities and model decontamination projects16by themselves, using available tools, in cooperation with organizations and experts withknowledge of radiation and sometimes with volunteers. These efforts mainly targeted local
facilities (or points) such as schools and specific houses. On the other hand, the notion was
gradually spread that decontamination of wide area was necessary to obtain sufficient effects
in air dose rate reduction.
Under these circumstances, to verify the effects of decontamination over relatively wide
areas with various land usage including housing, roads, agriculture, etc., the Cabinet Officeentrusted JAEA to start a demonstrative test in Date City and Minami-soma City under a“research project to formulate decontamination guidelines related to the accident at the
1FNPS”. In addition, to verify technologies for area-wide decontamination, the Fukushima
Prefecture implemented a wide-area decontamination model project. 17 In the meantime,different range and effects of decontamination among municipalities led to "sense of
unfairness" and "sense of dissatisfaction" of some residents.

13Source: Date City, “Three years of history of Date City after the Great East Japan Earthquake and Nuclear

Accident” (http://www.city.date.fukushima.jp/soshiki/9/7146.html)

14Source: Koriyama City, “History of Koriyama City after the Great East Japan Earthquake” (February 2013)15 Source:

Ministry of Education, Culture, Sports, Science and Technology (MEXT), “Air dose reduction
measures in the schoolyards and kindergarten yards based on fieldwork” (May 11, 2011)16For example, the Fukushima Prefectural Government's model project for radiation reduction measures forordinary houses
17Source: Fukushima Prefectural Government, Fukushima surface decontamination model project(https://www.pref.fukushima.lg.jp/sec/16045c/josen-mentekimoderu.html )5

Figure 1-2 Decontamination at Tominari Elementary School in Date City.

Decontamination
implementation area
Target spots for the decontamination

Residential land

Rice paddy

Area (㎡)

Roof

4,779

Wall

5,945

Garden, etc.

11,204

Rice field

11,350Field, Orchard

27,325

Surface of slope

20,705

Forest, Bamboo forest

16,339Municipal road

6,866

Land use map

Field, Orchard, etc

Forest, etc

Road

Private road, Farm road

148

Waterway

565

Others89

Total

Legend105,315

Decontamination
implementation area

Residential land,
SchoolRice paddy

ForestField, Orchard, etc.

Water storage tankOnami
elementary
schoolWater storage tank

The no n-colored section in the deco ntamination
implementa tion area shows the surface o f slope.
Route 115 o f natio nal highway

Figure 1-3 Target areas for decontamination of the area-wide decontamination model projectby Fukushima Prefecture18 .
JAEA continued enhancing its framework to support the decontamination of each municipality. In
addition, since October 2011, Fukushima Prefecture held workshops, in cooperation with JAEA, to develop
human resources for decontamination.
At the municipal level, Fukushima City created the manual mentioned in 3) and held workshops fordecontamination business operators, in order to develop human resources as well as to provide matching
opportunities for local business operators to utilize their own techniques to let them easily enter thedecontamination business19.

18Source: Fukushima Prefecture, "Fukushima Prefecture surface decontamination model project summary

version", (February 2012)19For example, through the workshop, a company specializing in painting and cleaning was found to be goodat high-pressure water cleaning, a company specializing in civil engineering was found to be good at

6

Apart from the above, regarding farmland, since May 28, 2011, MAFF took the initiative to
conduct demonstration tests, as seen in Figure 1-4, to verify decontamination technologies forfarmland soil in Iitate Village and Kawamata Town. On September 30, 2011, MAFF compiled
the publication, “Appropriate Methods for Decontamination of Farmland.” The results ofthese demonstration tests are included in the decontamination-related guidelines described in(4) 2) of this chapter.
MAFF continued efforts to develop decontamination methods. It started demonstration
project for development of farmland decontamination technologies in February 2012 20
including verification at the construction demonstration level and studies toward practicaluse in the field as shown in Figure 1-5. In February 2013, MAFF compiled the “TechnicalBook for Farmland Decontamination,” summarizing the features of each method as shown in
Figure 1-6.

Scraping top soil
using fixation agents
Itamizawa: Test area:
10 a
Cs radioactivity: 9,100
Bq/kg
Decontamination using
highly Cs absorption plants(sunflower/amaranth)
Nimaibashi: Test area: 15 a
Cs radioactivity: 7,700
Bq/kg

Decontamination bystirring soil
Itamizawa: Test
area: 4.2 a
Cs radioactivity:
15,300 Bq/kg○Demonstration tests inother areas
Upside down plowing(deepplowing)(paddy field)
Motomiya City: Test
area: 28 a Cs
radioactivity: 4,100 Bq/kg

Iitate Village
Kawamata Town

Numanodai
ra Clear
Center
Sunflower
incineration testDecontamination using
highly cesium absorption
plants (amaranth/others)
Yamakiya: Test area: 2 a
Cs radioactivity: 5,700
Bq/kg

Basic scraping of
the top soil (paddy
field)
Iitoi: Test area: 8 a
Cs radioactivity:
10,400 Bq/kg

Tearing off pasture
Iitoi: Test area: 0.5 a
Cs radioactivity:
13,600 Bq/kg

Cs radioactivity refers to the total
concentrations of cesium-134
and -137 in the soil (Bq/kg, dry soil)

Figure 1-4 Development of decontamination technologies for contaminated agricultural soil –Overview of the demonstration tests21 .

scraping of ground soil.
20Source: Ministry of Agriculture, Forestry and Fisheries (MAFF), “Results of the Demonstration Project for

Decontamination of Farmland (Interim Report)” and the “Technical Book for Farmland Decontamination”(August 31, 2012)
21Source: Ministry of Agriculture, Forestry and Fisheries (MAFF), "Development status of decontamination
technology in agriculture, forestry and fisheries" (June 16, 2012), (also the source for Figure 1-5)

7

FY2011

FY 2012FY 2013

Urgently need for Development of the
farmland decontamination basic technology

Verification at the construction
demonstration level

Efforts to further challenges toward practicaluse in the field①Scraping topsoil②Stirring/removing with water③Upside down plowing

Summarizing the construction method or
the like as a “Technical Book for
Farmland Decontamination” (Rural
Development Bureau)

Decontamination for farmland, etc

Nuclearaccident
occurrence

Ministry of Environment“Decontamination related Guidelines"
Development of decontamination work
equipment

Volumereduction

Migration
reduction

Tractor with radioprotection function
Ridges, Slopes, Farm roads, Waterway
decontamination devices
Upside down plows for decontamination

Technology development of the farmland decontamination in the high contaminated areas,
Advance of individual technology① Technology development of safe and efficient decontamination work
② Decontamination of paddy fields not being able to apply scraping top soil or upside
down plowing paddy field③ Search of the highly radioactive material absorption plants , Elucidation of theabsorption mechanism
Hillside pasture decontamination
work devices (FY2012)

Development of the prediction technology of the
dynamics of radioactive materials
Release path of the radioactive cesium fromfarmland soil and prediction of the emission

Elucidation of the migration factor of radiocesium and Development of migration reduction technology of radioactive materials to farm products
Products of nearly practical use/verification level: rice, forage crops, wheat, vegetables, fruit trees, teaProducts of study level: soybean, rapeseed

Development of volume reduction techniques for soil/crops and others containing radioactive materials[Contaminated disposal soil] Cesium removal technology by dry method (FY2011 ~),Cesium removal technology by oxalic acid (FY2012 ~)[Weed, rice straw, etc.] Pellet production equipment/Mobile carbonization apparatus(FY2011〜FY2012)

Scheduled to be introduced in stages in the field

Figure 1-5 Research plan of radioactivity decontamination measures for agriculture after the
nuclear accident.

Process

Scraping

Collecting/Tr
ansporting

Scraping~
Collecting/Tr
ansporting(continuous)

Scraping
methods

FeatureSoil watercondition

Surfacecondition

Deviceversatility

Operator
dependence

Scraping the
topsoil withbackhoe

Scraping the topsoil by moving bucket backand forth with backhoe

Wet~Dry

Rough~landleveling

High

High

Wiper

Scraping the topsoil by letting an arm swing
to a horizontal direction using the backhoe
fitted an edge to the bucket

Wet~Dry

Rough~landleveling

MiddleLow

Standardtransporting

Packing the scraped soil into theweatherproof large sandbags using backhoe
and carry it

Wet~Dry―High

Sucking

Sucking the scraped soil through suction
pump/hose using the sludge supply anddischarge car

Dry

Conveyor

Packing the scraped soil into theweatherproof large sandbags using the screw
conveyor type shaving machine

Dry

Skimmer

Scraping the topsoil with horizontally rotating
special resin plate and loading the scraped soil
into a followed truck for the non-leveling ofgroundDryland leveling

Low

MiddleTurf stripper

Scraping the topsoil by letting a lot of small
scoop-shaped blades rotate horizontally andloading the scraped soil into a truck runningparallel for the non-leveling of groundDry

land leveling

Low

MiddleRotary cutter

Scraping the topsoil using the lawnmower
with the rotary feather fixed to a backhoe andpacking the scraped soil into the weatherproof
large sandbags in the rearDryland leveling

Low

Middle――Middle

Low

―

―

―

Figure 1-6 Options of topsoil scraping methods22 .

22Source: Ministry of Agriculture, Forestry and Fisheries (MAFF), "Overview of the Technical Book of

Agricultural Land Decontamination Measures" (February 2013)83）Formulation of manuals for radiation dose reduction measures
As mentioned in 1.1.1, the knowledge of radiation and about its influences on the human body had notbeen shared sufficiently among ordinary people in Japan before the accident occurred. The accident
raised the need for general knowledge on radiation and for information on radiation protection measures
for the accident at 1FNPS, especially among people in the affected areas. Several academic organizations
with expert knowledge of radiation published Q&A-style radiation guidebooks to provide basic knowledge
and information on radiation to the public23. The Government and Fukushima Prefecture also issued somepamphlets regarding radiation.
In addition, Fukushima Prefecture, Minami-soma City, and Fukushima City publishedseveral manuals for radiation dose reduction measures24, which contributed to provide people
with knowledge not only on radiation but also on decontamination.
Based on these guidelines as well as the results of decontamination activities shown in 2) just above,some municipalities formulated and announced their first decontamination implementation plans based on
the “Basic Policy on Urgent Implementation of Decontamination” (to be explained in the following (4)) as
early as in the autumn of 201125.
The government incorporated the contents of these manuals issued by Fukushima Prefecture andmunicipalities and the knowledge obtained through decontamination activities including model projects
into the “Decontamination Technology Catalog” and the “Decontamination Guidelines” as indicated in (4)2).

23For example, “Radiation Q&A in Life Answered by Experts” issued by the Japan Health Physics Society,“The Q&A Regarding Radiation Exposure” issued by the Japan Radiological Society, and “The Q&A
Regarding the Impact of Radiation Exposure on the Human Body in Association with the 1FNPS Accident”
issued by the Japanese Radiation Research Society.
24Examples are: Guidance for Reduction of Air Dose in Living Space issued by the Fukushima Prefectural
Government (July 15, 2011), Radioactive Material Decontamination Manual issued by the Minami-soma
Municipal Government (July 2011), and the Fukushima City Decontamination Manual (1st Ed.) issued by
the Fukushima Municipal Government (September 27, 2011).
25For example, Date City Decontamination Implementation Plan (1 st Ed.) (October 2011); Fukushima City
Furusato Decontamination Implementation Plan (September 27, 2011);
Kawauchi Village Decontamination Implementation Plan (1st Ed.) e (September 28, 2011); and Minami-soma
City Decontamination Plan (1st Ed.) (November 10, 2011)9Figure 1-7 Excerpt from a brochure on radiation (left) and a guide book on decontamination(right) published by Fukushima Prefecture26 .

（4） Establishment of legal framework and decontamination guidelines
1）Framework of decontamination under the Act on Special Measures and others
While the knowledge about radiation and decontamination was gradually being collected
and assembled, as described above, Chairperson of the Environment Committee of the lower
house of the Diet presented a bill of the Act on Special Measures Concerning the Handling ofEnvironmental Pollution by Radioactive Materials Discharged by the Nuclear Power Station
Accident Associated with the Tohoku District Off the Pacific Ocean Earthquake That
Occurred on 11 March 2011 (Law No. 110, 2011) (hereinafter referred to as the Act on Special
Measures). The Act was enacted on August 26, 2011 at the upper house plenary session andpromulgated on August 30, 2011.
The NERH decided、on August 26, 2011, the Basic Policy on Urgent Implementation of
Decontamination27 as an initiative until the full enforcement of the above act (due January 1,2012).
The above basic policy stipulated: the decontamination should be operated by the national
government for the evacuation areas;, the annual additional exposure dose should be limited
to 1 mSv or lower as a long term goal in the region under existing exposure situation(currently 20 mSv or lower for the annual additional exposure); and the national government
should provide technical and financial support for local municipalities to develop andimplement their decontamination plans. In addition, a fund was created by the
supplementary budget of the Cabinet Office to let Fukushima Prefecture subsidize (at a26Source: Fukushima Prefecture, "To understand radiation correctly and behave properly" (September 2011),

and "Guidance related to radiation dose reduction measures in the living space" (July 15, 2011)27Source: Nuclear Emergency Response Headquarters (NERH), Basic Policy on Urgent Implementation of

Decontamination (August 26, 2011)10

subsidy rate of 100%) the municipalities for decontamination based on their decontaminationplans in accordance with the Urgent Implementation Policy.
The same basic policy further stipulated that the national government should continuously
provide technical information necessary for the decontamination such as, on effective
methods, their cost, and considerations due (the Decontamination Technology Catalog),
through model projects in each area, including particularly high dose areas. In this regard,
the NERH presented the “Guidelines for the Implementation of Decontamination in
Municipalities 28 ” for relevant municipalities to formulate and implement theirdecontamination plans.
On November 11, 2011, the Basic Principles on the Act on Special Measures was authorized
by the Cabinet. Taking over the concept of the Basic Policy on Urgent Implementation of
Decontamination Works, the new Basic Policy stipulated that the annual additional exposure
dose would become below 1 mSv in the long-term in the area where the annual additional
exposure dose was currently below 20 mSv, and that the national government was responsible
for treating the wastes and wastewater sludge exceeding a certain level of radioactivity.
In the meantime, on October 29, 2011, the MOE announced the “Basic Concept of theInterim Storage Facility (ISF) Necessary in Dealing with Environmental Pollution Caused byRadioactive Materials in Association with the Accident at the 1FNPS of TEPCO,” which
stipulated the policies to install the interim storage facility at one location in Fukushima
Prefecture for handling contaminated soil and wastes produced in the prefecture and to
finally dispose of such waste outside Fukushima Prefecture within 30 years after starting ofinterim storage.
On December 22, 2011, the MHLW promulgated the “Ordinance on Prevention of Ionizing
Radiation Hazards Associated with Decontamination Works to Decontaminate Soil andWastes Polluted by Radioactive Materials Resulting from the Great East Japan Earthquake”(hereinafter referred to as the Ionizing Radiation Ordinance for Decontamination), a
framework to prevent the ionizing radiation hazards associated with decontamination work.
By such legal arrangements, the legal framework for implementing decontamination workin Japan has been fixed.

2）Decontamination guidelines
On November 22, 2011, the Cabinet Office issued the “Decontamination Technology
Catalog” and on December 14, 2011, the MOE formulated and published the“Decontamination Guidelines” that systematically compiled the decontamination methods inaccordance with the Act on Special Measures. The guidelines based on the Act on Special
Measures explained in an easy-to-understand manner the processes to survey and measure
the extent of contamination, implement the decontamination, and collect, transport, and store
removed soil associated with decontamination work (See Chapter 2 for details).
On December 22, 2011, simultaneously with the announcement of the Ionizing Radiation
Ordinance for Decontamination, the MHLW formulated and announced the “Guidelines forPrevention of Radiation Hazards to Workers Engaged in Decontamination Works,” which are
the guidelines to prevent health hazards to workers associated with decontamination
operations.
On December 27, 2011, the MOE formulated and announced the “Waste Guidelines” (theguidelines for processing waste contaminated by nuclear accident-derived radioactive
materials).
In March 2012, the MOE formulated and announced the “Guidelines for Addressing
Localized Contaminated Spots by Radioactive Materials,” which are the guidelines
summarizing the efficient locating methods, in-depth survey methods, and handlingprecautions of localized contaminated spots.
Most of the guidelines were thus developed toward the end of JFY2011.ｊ
28 Source:

Nuclear Emergency Response Headquarters (NERH), Guidelines for the Implementation of
Decontamination in Municipalities (August 26, 2011)11

（5） Efforts toward the full-fledged decontamination under a unified framework
1）Decontamination projects by the Cabinet Office
In response to the establishment of the Basic Policy on Urgent Implementation of
Decontamination Works, the Cabinet Office entrusted the project for a decontamination
model to JAEA. The project primarily targeted the areas with annual additional exposure
dose exceeding 20 mSv and had the aims of establishing efficient and effective
decontamination methods and measures of radiation protection for workers (started in
November 2011; see 1.1.6 for details).
The Cabinet Office also delegated the project to demonstrate decontamination methods to
JAEA, in order to publicly solicit new decontamination technologies that can be practicableand to evaluate their effectiveness.

2）Cold shutdown state of nuclear power station and rezoning of the evacuation areas
On December 16, 2011, the NERH judged that the safety of the entire power station wascomprehensively secured by the achievement of the cold shutdown state of the reactors. Thus,
it was confirmed that the target of step 2 in the roadmap, a state where “the release ofradioactive materials came under control and the radiation dose was significantly
suppressed,” was achieved.
Under this situation, on December 26, 2011, the NERH compiled the “Basic Concept andFuture Tasks in Review of the Restricted Areas and the Evacuation Order Areas after theCompletion of Step 2”; the basic concept to start a concrete review of the restricted areas andthe evacuation order areas, including the preparation for lifting the evacuation order of theareas with low dose rates by further advancing the decontamination work, with the targetedtime schedule to finish the review by March 30, 2012.
In response to the above, on January 26, 2012, the MOE announced the “Decontamination
Policy of the Special Decontamination Area” (Decontamination Roadmap),” describing theflow of decontamination projects (demonstration model projects, preliminary decontamination,and full-scale decontamination) and the processes for each area.
As for lifting of evacuation orders, it was prescribed that development of livelihood
infrastructures and restoration of municipal office functions should be promoted together
with decontamination because the objective of lifting of evacuation orders was to assure
returning of residents and reconstruction of their lives.

3）Establishment of a system toward full-scale decontamination
On August 24, 2011, before the establishment of the Act on Special Measures, the Fukushima
Decontamination Promotion Team was established mainly by the MOE in cooperation with the Cabinet
Office and JAEA to support the formulation of decontamination implementation planning by municipalities
in Fukushima Prefecture. The team started its operation in September 2011, immediately after the
promulgation of the Act on Special Measures, in cooperation with the Nuclear Emergency Response Local
Headquarters (hereafter referred to as the Local NERH)), to communicate and coordinate withmunicipalities and to help the formulation of decontamination plans (including dispatch of experts). The
team also promoted the national decontamination model projects in twelve municipalities in the restricted
area, deliberate evacuation areas, etc .
In academic and private sectors, in May 2011, the Atomic Energy Society of Japan (AESJ) establishedthe “Clean-up Subcommittee29” to actively provide support to the restoration activities of environmental
contamination by radioactive materials. In November 2011, the “Society for Remediation of Radioactive
Contamination in the Environment (SRRCE) 30 ,” which was mainly dealing with the subject of
29Source: Fukushima Special Project, Clean-up Subcommittee, Project Leader Tadashi Inoue, The objectivesof the establishment of AESJ CU Subcommittee and its activities (January 20, 2013)

30Source: The Society for Remediation of Radioactive Contamination in the Environment (SRRCE) Website(http://khjosen.org/）12

decontamination, and the “Technical Advisory Council on Remediation and Waste Management 31” byindustry groups, were established.
On January 4, 2012, upon the full enforcement of the Act on Special Measures, the MOE established the“Fukushima Environmental Restoration Office” as a base to promote decontamination and revive thenatural environment in Fukushima Prefecture. To promote decontamination in the Special Decontamination
Area, the office coordinates the operations with eleven municipalities in the same areas, implements
decontamination projects, and coordinates or cooperates with the Local NERH. In addition it consults andcoordinates plans and project details of decontamination implemented by municipalities in Fukushima,
Miyagi, and Iwate Prefectures. The office has five branches in Fukushima Prefecture to provide detailed
support to municipalities (in addition to the five branches, on December 5, 2014, the Hamadori Office for
the Interim Storage Facility was fonded to address the issues of the interim storage facility)32.
On January 20, 2012, the Decontamination Information Plaza was jointly established near Fukushima
Station by the MOE and Fukushima Prefecture to play the role of base facility to provide the general publicwith information on decontamination and radiation and to dispatch registered experts. The structure toward
full-scale decontamination was steadily being built. JAEA and AESJ dispatched expert personnel to the
Decontamination Information Plaza and the Fukushima Environmental Restoration Office.
On March 12, 2012, TEPCO established an office under the organization of the Environmental
Department in its Fukushima Office to monitor the environmental radiation by resident employees and toprovide support for the decontamination efforts in Fukushima. From April 7, 2012, the Federation ofElectric Power Companies of Japan dispatched decontamination experts to support the decontamination
activities in Fukushima, in addition to providing personnel to the Decontamination Information Plaza uponrequest.
In addition, the Japan Society of Civil Engineers (JSCE) established the “Specific Theme Committee toAddress Radioactive Waste” under the “Great East Japan Earthquake Special Committee,” to carry out
full-fledged activities from the beginning of 2012 33. In April 2012, the Japan Federation of Construction
Contractors established the Decontamination Committee under the Electric Measures Special Committee toestablish the framework to implement decontamination projects for the entire construction industry.
On January 1, 2013, TEPCO established the “Fukushima Revitalization Headquarters” and theDecontamination Promotion Office within it to provide further cooperation on decontamination.
As seen above, with the establishment of the Act on Special Measures, the efforts and roles of national,
prefectural, and municipal governments were restructured. As their roles were more clearly defined(Fig.1-8) and as their features became to be more utilized, the entire structure in Japan was optimized, andsystematic cooperation between industry and academia was accelerated.
In the meantime, from February 8, 2012, the Fukushima Prefectural Government held meetings of theStudy Committee for the Basic Concept of Environmental Recreation Strategic Base34. The committeestudied the establishment of the “Center for Environmental Recreation,” the base facility to address therestoration and recreation of the environment contaminated by radioactive materials, under close
cooperation among Fukushima Prefecture, JAEA, and the National Institute for Environmental Studies(NIES). The center is scheduled to open in FY2016 (a part of the facility is opening in FY2015) to provide
residents with information such as monitoring of environmental radioactivity, status of the environmental
decontamination for the remediation and recreation of the environment, tracking movements of radioactive
materials, research and evaluation of decontamination methods, and the results of monitoring and surveys,
and in addition to provide education, training, and exchanges to develop creative power for Fukushima's
future35.

31Source: Technical Advisory Council on Remediation and Waste Management Website(http://tacrwm.jp/01_about/01_01_objective.html)

32Source: Ministry of the Environment (MOE): "Fukushima environmental remediation office"33Source: Japan Society of Civil Engineers: JSCE Great East Japan Earthquake Special Committee - One

Year of Activities, Achievements, and Proposal (March 2012)
34Source: Fukushima Prefecture Website（https://www.pref.fukushima.lg.jp/sec/16035d/meeting-basicplan.html ）35Source: Center for Environmental Recreation Operative Strategy Meeting: Mid- and long term policy for theenvironmental recreation center (February 2015)13

Government approach

Prefecture approach

Municipalities approach

Basic Policy for Emergency Response on Decontamination Work

August 26, 2011 Nuclear Emergency
Response Headquarters, Decision

Act on Special Measures Concerning the Handling of Radioactive Pollution

August 30, 2011,Promulgation,
Enforcement of the part

East Japan earthquake recovery andreconstruction reserve fundSecuring of about ¥ 220 billion yen
September 9, Cabinet decision

Funds for decontamination and related
works

Funds fordecontamination
and related
works

Implementation of the decontamination
model project (since November)
Implementation of demonstration model
project of decontamination
technology(since November)

Implementation of Fukushima Prefecturesurface decontamination model project(since November)
Implementation of Fukushimadecontamination technology demonstration
operation (since December)Preparations
for public
infrastructure

Decontamination of public office by the
Self-Defense Forces (December 7 to 19)

Pre"Decontamination practice guidelines
by municipalities" (August 26,
determined by the Nuclear Emergency
Response Headquarters)

Budgetary
provisionDevelopment of "decontamination
technology Catalog", "decontamination
related guidelines"

Implementation of briefing session to themunicipalities about decontamination
Dispatch of experts

Development of "Decontamination
plan" in the municipalities
Formulated alreadyDevelopment of "Guidance related toradiation dose reduction measures in theliving space" (revised October 31)

Holding of "decontamination work seminar"
Publication of the "Basic policy on thecleanup activities for living area," "Suitable
methods for decontamination of farmland
and forests."

Decontamination practice guidelines bymunicipalities" (August 26, determined by
the Nuclear Emergency Response
Headquarters)

Holding of "decontamination work seminar"
Holding of "Safety and security forum"

Fukushima-City, Nihonmatsu-City,
Date-City, Motomiya-City, KooriTown, Kunimi-Town, KawamataTown, Otama-Village, Koriyama-City,
Tamura-City, Kagamiishi-Town,
Asakawa-Town, Miharu-Town,
Shirakawa-City, Nishigo-Village,
Izumizaki-Village, Nakajima-Village,
Yabuki-Town, Tanagura-Town,
Shinchi-Town, Soma-City,
Minamisoma-City, Hirono-Town,
Kawauchi-Village, Iwaki-City：25
municipalities (As of December 28,
2011)

Development of "municipal decontamination
planning manual"
Dispatch of experts and volunteers

January 1, 2012, full「Act on Special Measures Concerning the Handling of Radioactive Pollution」(full-scale decontamination start) enforcement
On January 4, 2012, opened the "Fukushimaenvironment revitalization office" inFukushima
Development of decontamination
implementation plan by government

Implementation of full-scaledecontamination by government

Fukushima Prefecture
Various approaches for thedecontamination① Financial support② Technical assistance③ Human support

Special decontamination area
・Designated areas
Designated areas of destricted area ordeliberate evacuation area (11municipalities)
Goal of the decontamination in theareas with not less than 20mSV/year
・Reduce those areas progressively andquickly
Goal of thedecontamination

Development of decontamination
implementation plan by municipalities

Implementation of full-scaledecontamination by municipalities
Priority investigation areas of pollution
situation
・Designated areas
Areas with not less than the radiationdose of 0.23μSV/year (102 areas)

Goal of the decontamination in the areas with less than 20mSV/year
・Long-term goal：less than 1mSV/year
・Annual additional exposure dose:
About 50% reduction by the end of August, 2013 compared to the end of August,2011
・Performing the decontamination in children's life environment with priority.
Annual additional exposure dose in those areas:
About 60% reduction by the end of August, 2013 compared to the end of August,2011

Goal of the decontamination in territories other than the areas with particularly high annual additional exposure dose
By the end of March, 2014, performing the action of decontamination in buildings such as housing, offices, public facilities, etc., roads,
farmland, and forests surrounding living area,
and transporting the removal soil produced from there to the temporary storage successively

Figure 1-8 Decontamination approaches by government, prefectural and municipal
authorities36 .

In October 2011, the International Atomic Energy Agency (IAEA) visited Fukushima, reviewed thedecontamination works performed by Japan and provided advice on them. The results were compiled in theform of the “Final Report by the International Mission Regarding Remediation of Large Contaminated
36Source: The nuclear disaster victims life support team by the government: “Interaction with the public,

newsletter No. 9 ‘ (News from the nuclear disaster victims life support team by the government)” (January
15, 2012)

14

Areas Off-site the Fukushima Daiichi Nuclear Power Plant.” The report described nine areas of significant
improvement and gave recommendations on twelve points to the Japanese government.
Examples of nine highlights of important progress and recommendations on twelve points
which were described in the Final Report 37 by the International Mission Regarding
Remediation of Large Contaminated Areas Off-site the Fukushima Daiichi Nuclear Power
Plant38.
【Examples of nine highlights of important progress】
The Mission Team appreciates that Japan has gone forward very quickly and allocated thenecessary legal, economic and technological resources to develop an efficient remediation
programme to bring relief to the people affected by the Fukushima Dai-ichi nuclear accident.
Priority has been given to children and the areas that they typically frequent.
The Fukushima Decontamination Promotion Team, which consists of resident staff inFukushima from the Ministry of the Environment (MOE), the Local Emergency Response
Headquarters and the Japan Atomic Energy Agency (JAEA), coordinates and shares information
with relevant ministries and agencies, and communicates with and provides technical support to
the Fukushima prefectural and relevant municipalities. The Mission Team welcomes Japan’s
efforts to establish a practical catalogue of remediation techniques
The Team considers the use of demonstration sites to test and assess various remediation
methods to be a very helpful way to support the decision-making process.

【Examples of recommendations on twelve points】
The Japanese authorities involved in the remediation strategy are encouraged to cautiously
balance the different factors that influence the net benefit of the remediation measures to ensure
dose reduction. They are encouraged to avoid over-conservatism which cannot effectively
contribute to the reduction of exposure doses. This goal could be achieved through the practicalimplementation of the Justification and Optimization principles under the prevailingcircumstances. Involving more radiation protection experts (and the Regulatory Body) in theorganizational structures that assist the decision makers might be beneficial in the fulfillment of
this objective. The IAEA is ready to support Japan in considering new and appropriate criteria.
It is appropriate to consider further strengthening coordination among the main actors, throughthe establishment of a more permanent liaison between the organizational structures of theGovernment of Japan and the prefectural and municipal authorities.
Before investing substantial time and efforts in remediating forest areas, a safety assessment
should be carried out to indicate if such action leads to a reduction of doses for the public. If not,efforts should be concentrated in areas that bring greater benefits. This safety assessment
should make use of the results of the demonstration tests.

（6） Progress of decontamination in the Special Decontamination Area and the Intensive
Contamination Survey Area
1）Progress of decontamination in the Special Decontamination Area
The decontamination in the Special Decontamination Area (see 1.1.5 for details) wasstarted from the peripheral areas of municipal offices by the Self-Defense Forces, which would
serve as the bases for full-scale decontamination activities later. Also, the decontamination of
37Source: IAEA, ”Final Report of the International Mission on Remediation of Large Contaminated Areas

Off-site the Fukushima Daiichi Nuclear Power Plant” (November 15, 2011)(http://www.mofa.go.jp/mofaj/saigai/pdfs/iaea_mission_1110_en.pdf )38Source: Excerpt from IAEA “Final Report of the International Mission on Remediation of Large
Contaminated Areas Off-site the Fukushima Daiichi Nuclear Power Plant; Draft translation (Summary
portion only)” (November 15, 2011)15

future operational bases such as other public facilities was made by the MOE. Additionally,
the decontamination model projects were started in March 2012 in the restricted area of the
Joban Expressway, an important piece of transportation infrastructure. These activities wereconducted as part of overall strategic efforts, which had the objectives of establishing effective
decontamination methods, while obtaining data to help implement smooth large-scaledecontamination, instead of just conducting large-scale decontamination without a strategy.
The progress in review of evacuation zoning differed by municipality in the Special
Decontamination Area. On March 30, 2012, zoning in parts of the restricted areas in Tamura
City, Kawauchi Village, and Minami-soma City were changed and these were newly
designated as evacuation order areas. In April 2012, the MOE formulated decontamination
implementation plans for Tamura City, Naraha Town, Kawauchi Village, and Minami-soma
City, earlier than for other municipalities. On July 25, 2012, the MOE started the firstfull-scale decontamination in the Special Decontamination Area in Tamura City. Then,although there were differences in progress among municipalities in the Special
Decontamination Area, the decontamination plans were gradually formulated, followed byfull-scale decontamination.
According to the Act on Special Measures, the consent of a large number of concerned
parties was required before starting the decontamination. It took a very long time to identify
the land owners and stakeholders, to pay attention to residents' feelings, and to provide
considerations and detailed explanations to obtain consent of all involved. Furthermore, withthe large- and full-scale decontamination works having started, the operators were required
to secure a large number of workers, provide education on labor safety and decontamination
works, and secure qualified workers. Each operator made various efforts to address thesemounting tasks. In the meantime, the national government kept collecting knowledge andinformation on new discoveries from actual decontamination works, shared the information
with the public in a timely manner, and reflected such summaries in the form of specifications
to the decontamination business operators (See Chapter 4 for details).

2）Progress of decontamination in the Intensive Contamination Survey Area
In the Intensive Contamination Survey Area (see 1.1.7 for details), some municipalities had
already conducted the decontamination before the full enforcement of the Act on Special
Measures. They utilized the knowledge obtained from their experiences and continued thedecontamination after the enforcement of this Act.
For example, based on the experience that it was important to form a consensus with local
residents before starting the decontamination, Fukushima City allowed the residents'
involvement from the planning stage of decontamination as shown in Figure 1-9. The city
established 18 “regional decontamination measure committees” consisting of officers of theautonomy promotion council, PTA, and local city council members. The city also conducted“decontamination implementation review meetings,” consisting of leaders of neighborhood
associations to confirm the flow of rainwater and surface water in each community and study
the work orders for decontamination. Minami-soma City made efforts to seek agreement
among residents to secure temporary storage sites by establishing the selection criteria forcandidate sites by themselves and explaining them to residents as shown in Table 1-1. In
Kawauchi Village, dosimeters were distributed to all families, so that residents themselves
were able to measure the dose before and after decontamination.
Such efforts to involve residents in the decontamination were also seen in several
municipalities outside Fukushima Prefecture. For example, in Kashiwa City, Chiba
Prefecture, the “Dialog Meeting toward Safe Living organized by the Association to Promote
Decontamination in Kashiwa City 39 ” was held during November 21-23, 2011, to havesufficiently long discussions with citizens. Consequently, the city formulated its
39Source: Kashiwa City Website（http://www.city.kashiwa.lg.jp/soshiki/080800/p010072.html）

16

decontamination implementation plan in March 201240. In the case of Kashiwa City, as aresult of the above efforts, the decontamination implementation plan allowed much
involvement of citizens by stipulating enhanced support for citizens and volunteers in thedecontamination implementation.
On the other hand, some municipalities were not able to establish temporary storage sites.
Some took a long time to decide the scope of decontamination and the formulation of thedecontamination implementation plan because they were not able to reach agreement withresidents.

Regional decontamination measure committee

Explanation of decontamination contents to regional decontamination measure committee

Decontamination implementation review
meeting,

Decision of decontamination order with decontamination implementation review meeting
consisting of leaders of neighborhood associations

Briefings to residents

Understanding of the common decontamination procedure through the residents briefing

Sending consent form / inquiry

Field survey / Dose measurement

Filling out consent form/inquiry and sending backInvestigation / measurement of each house by decontamination operators

Individual meeting

Decontamination operator visits all houses and has the meeting with the inhabitants fordetailed decontamination contents. The city check the contents (sentences) later and thenthe city office staff or a supervision personnel attends to the decontamination works.

Dose measurement before decontamination

Monitoring before decontamination, Notification of the measurements (quick estimation)

Decontamination work

・Decontamination work based on the decontamination management standard(The decontamination management standard which specified the decontamination worktarget is developed and the decontamination work is managed based on it so that thedifference doesn't occur to decontamination result (achievement) in eachdecontamination work)
・Supervision of the decontamination work by the decontamination manager entrusted by
the city

Figure 1-9 Procedure for housing decontamination (Fukushima City)41 .

40Source: Kashiwa City Website（http://www.city.kashiwa.lg.jp/soshiki/080800/p011077.html）
41Source: Fukushima City, "An approach to the decontamination in Fukushima City" (February 28, 2013)17

Table 1-1 Criteria for selecting candidate site for temporary storage42
Viewpoint

Items for selecting
site

Criteria for electing
site

ReasonSecuring of site area

Securing of site area
not less than
10,000m2

Production of a large
amount of removed
radioactive
substances

Securing of accessroad

Securing of accessroad not less than
two traffic lanes

Access of large
vehicles and heavy
industrial
machinery, etc.

Use of landDistance from thesurrounding housing,school and hospital,
etc.
Environment
protection

Risk of secondary
disaster
Influence of water
quality, animals andplantsCost performanceWith or without site
renovation
With or without siteacquisition

Distance between
candidate site andthe neighboringhouses, school andhospital, etc.
Outflow ofradioactive materials
and geologicalfeatureNo influence onwater quality,
animals and plants.
Preparation of sites
suitable for storage
and control of theremoved soil
Site acquisition in
the case of non-public
landLand ownerLand owners'
cooperation andunderstanding in thecase of non-public
land

Agreement with local
residents

Cooperation andunderstanding of thesurrounding
residents

Agreement

Impact on
consensus

Impact on
decontamination
work schedule andproject costs

Impact on
decontamination
work schedule（7） Efforts based on the experiences of decontamination
On October 23, 2012, the MOE compiled the “Decontamination Promotion Package,” inorder to accelerate the decontamination works and eliminate anxiety among residents. The
above package recommended measures to accelerate decontamination works, such as transfer
of authority to the Fukushima Environmental Restoration Office, expansion of outsourcing of
42Source: Minami-soma City, "The situation of the decontamination in Minami-soma City" (October 22, 2013)18

the negotiation of obtaining residents' consent to the private sector, and securing of
decontamination workers from a wide area. Moreover, it further recommended the measures
to obtain residents' consent and eliminate anxiety among residents, which was the major
problem then, such as disclosure of information about the effects and progress of
decontamination and strengthening of risk communication about decontamination.
Then, in November 2012, the “progress of decontamination in the Intensive Contamination
Survey Area” was announced, and in March 2013, the “progress of decontamination in theSpecial Decontamination Area” was announced, more publicly disclosing the overall progressof decontamination.
In the meantime, in January 2013, one year after the full enforcement of the Act on Special
Measures, upon receipt of reports about questionable decontamination operations, the MOE
immediately established the headquarters for proper decontamination promotion toinvestigate the questionable cases. At the same time, the Ministry compiled the “appropriate
decontamination program” consisting of three items: (1) enhancing established work
responsibilities of business operators through unannounced inspections; (2) building a wide
range of management systems by using effective monitoring by a third party; and (3) using
the MOE organization effectively such as designating a telephone hotline to accept reports
regarding questionable decontamination operations. Through these measures, the MOE tried
to eliminate questionable decontamination operations and recover the confidence of residents.
Furthermore, based on the knowledge to the date, the MOE formulated the second editionof the Waste Guidelines in March 2013 and the second edition of the Decontamination
Guidelines in May 2014. In April 2013, the MHLW formulated the “Guidelines to Prevent
Radiation Hazards of Workers Engaged in the Disposal of Radioactive Materials Discharged
by the Accident. Thus various guidelines were revised or expanded based on the experiencesof decontamination progress.
In addition, with accumulation of good practices, in May 2013, the Fukushima
Environmental Restoration Office compiled the “Examples of Good Practices in
Decontamination” and distributed its copies to the decontamination business operators. Thisbooklet introduced two categories of good practices with seven examples each: one category istechnical good practices such as survey measurement technologies, decontamination
technologies and decontamination operation management technologies, and the othercategory is communication good practices with the residents including the promotion ofunderstanding and risk communication (See Figure 1-10 for examples).
On June 29, 2013, the full-scale decontamination operations that were the first full-scale
project in the Special Decontamination Area were completed in Tamura City.

19

Example 1 of the approach: Measurement of the spatial dose rate in high places such as roof andrain gutters(Fukushima City, Koori Town)[Challenge]
The grasp of the accurate pollution status of target facilities is necessary to promote thedecontamination efficiently and to control its quality. In addition, the simplified measurement
technique such as without footings is required when the measurement of the spatial dose rate inhigh places such as roof and rain gutters is required.

[approach]
By attaching a radiation measurement device to the tip of the long things such as extension pole or
wash-line pole, it was done that the measurement personnel could measure the spatial dose rate inhigh places from the ground. With this method, it can be made easily to measure the spatial dose
rate in high places.
Example 1) Example of Fukushima City：
With attaching the sensor of the NaI scintillation counter to the tip of the wash-line pole, air dose
rates in the vicinity of a height of approximately 3m can be measured from the ground.
Example 2) Example of Koori Town:
With attaching a small video camera, a small radiation dose measuring instrument andcommunication a small radiation dose measuring device to the tip of the pole, the system which canreceive the picture of the video camera with a monitor at hand was built.
By photographing together the measurement instrument display screen and the surrounding
landscape with the video camera, pollution and radiation dose of the corresponding location can be
confirmed on the ground monitor (tablet screen).

[Reference photograph]
Example 2) Example of Koori-Town:○Measurement scenery

Measurement
situation of the dose in
the gutter on the roof
top

Display of themeasurements on thetablet screen

Combination status of
the video camera anda small radiation
measuring instrument

Figure 1-10 A good practice: Measurement of air dose rates in high places such as rooves andrain gutters43 .

43Source: Fukushima Environmental Restoration Office of the Ministry of the Environment "Good practices ofdecontamination " (May 2013)20

（8） Comprehensive review of the decontamination progress and review of thedecontamination implementation plans in the Special Decontamination Area
In September 2013, the MOE announced the “Comprehensive Review of theDecontamination Progress.” The review indicated the variations in progress among
municipalities, because of the time required for reaching agreement with residents andsecuring temporary storage sites, and also the weather conditions such as winter snowfalls(Figure 1-11).
In particular, it was difficult to secure the sites for temporary storage and to acquire theconsent for decontamination. Some residents were angry to have their area be selected as
temporary storage for the wastes that they were not responsible for. Some feared that thetemporary storage site ultimately would become the final disposal site without due
consultation. Some feared the accumulation of contaminated soil. Some had different opinions
about how to operate the decontamination. In all cases, because of the basic policy to fully
respect the will and consent of residents before proceeding with the decontamination, there
was no way but to build a trusting relationship and improve the understanding about
temporary storage and decontamination. In this regard, not only the national and the local
governments, but also the decontamination business operators and each worker madestrenuous and consistent efforts.

・Since the situations of decontamination were different in each municipality, there was the variation in the progress of decontamination
among municipalities. The importance of dealing with future issues based on the experience until now and promoting the decontamination inconnection with the progress of restoration was enhanced. indicated the variation in progress among municipalities,
・The original target schedule was revised to allow a flexible decontamination schedule in accordance with the situation of each municipality
after consulting with local inhabitants.
Review of the current
situations

Since the situations of decontamination were different in each municipality as described below, there
was the variation in the progress of decontamination among municipalities.

Cases which needed the time for adjustment before starting
decontamination are as follows;
・Review of the decontamination areas, development of thedecontamination plan
・Securing the site for temporary storage, Obtaining informed
consent for decontamination
・Corresponding to the concern about the influence on healthof radiation and the effect of the decontamination
・Corresponding to the worry about that a transfer destinationof the removed soil is not clear, because a plan for theestablishment of interim storage installation isn't fixed.

Cases which needed the time for the conditions of thedecontamination site are as follows;・Natural influence such as snowfall
・Addition of compensation duties
・Development of the work procedures and thedecontamination schedule in accordance with the situationof each municipality and progress of restoration.

Future challenges based on experience

Coordination with the situation of restoration

・Ensuring of workers (labor-intensive decontamination work)
・Enhancement of safety measures(beginner for many workers)
・Load to traffic and waste disposal treatment (movement of theworkers and transportation of the removed soil, processing ofwaste generated from the worker lodgings)

・Facilitation of coordination between the decontamination
work and restoration projects (infrastructure preparation,
restoration base servicing, changeover of land use, etc.)
・Review of the decontamination implementation plan based on
the returnees expected timing
・Review of the decontamination implementation plan taking
into account the differentiation of the indication of residents’
will on their intention of return and the time,

Future direction
・Revise the original target schedule, which would complete the decontamination and transfer the waste and soils to temporarystorage without exception within two years, and promote the decontamination schedule in accordance with the situation of eachmunicipality and progress of restoration.
・In that case, in addition to taking appropriate measures for acceleration and facilitation of decontamination, reconsider theoriginal schedule of the decontamination flexibly in accordance with the situation of each municipality and progress of restoration.
・In Tamura City, measures of the decontamination and related works based on the decontamination plan were completed. In
Naraha Town, Kawauchi Village and Okuma Town , completion of the decontamination will be aimed at by the end of fiscal year
2013 according to the current decontamination plan. In Minamisoma City, Iitate Village , Kawamata Town , Katsurao Village ,Namie Town and Tomioka Town , the present decontamination plan is continued to be adjusted with each municipality, and will
be changed by the end of the year. In Futaba Town, the adjustment is continued to be performed with the municipality towards
the development of the decontamination plan in connection with the consideration of the progress of restoration

Figure 1-11 Review results of the current decontamination plans, etc. in the Special
Decontamination Area44 .
44 Source:

Ministry of the Environment (MOE), “Overall review of the progress of decontamination"

21

Therefore, the original target schedule, which would “complete the decontamination and transfer thewaste and soil to temporary storage sites in all cases within two years,” was revised to allow a flexible
decontamination schedule in accordance with the situation of each municipality and progress of restoration.
Then where the progress differed by municipalities, the plans were revised to better fit with the actual
situation. Also reviewed was the conventional way of forest decontamination that had been previously
conducted in a range of about 20 meters from the forest edge. In the revision, for the forest surrounding theresidential areas in valleys with high dose rates as shown in Figure 1-12, if the dose rates in the areasurrounding the residential area was still relatively high after area-wide decontamination, effective
decontamination exceeding the 20-meter range from the forest edge was allowed on an exceptional basis.
In the meantime, the Forestry Agency, working from the viewpoint of forestry regeneration, has
implemented a demonstration project to integrally promote the forest maintenance and measures against
radioactive materials. As a demonstration project, in forests in the Intensive Contamination Survey Area,
forest maintenance practices such as thinning were mainly operated by public entities of the prefecture andmunicipalities. Also, through conducting the disposal and reducing the amounts of foliage generated fromforest maintenance, and through creating wood fences to control the diffusion of radioactive materials, theForestry Agency has conducted efforts to collect knowledge necessary for the smooth maintenance offorests in the areas affected by radioactive materials.
In December 2013, the review of each decontamination implementation plan based on thecomprehensive review was conducted and the “Review of the Decontamination Implementation Plans in
the Special Decontamination Area” was announced.

Area A (forest surrounding the residential areas)・If the effect of decontamination with the removal of the deposited organic matter such as fallen leaves, can not be obtained, it is permitted to remove
the residue of accumulated organic matter additionally in a range of 5-meter from the forest edge as a rough indication (as the outflow of sedimentis concerned, preventive measures against it such as the setting of the sandbag must be appropriately carried out depending on the situation in thefield).
・For the forests surrounding the residential areas in valleys with high dose rates , effective decontamination work beyond 20-meters from the forestedge may be exceptionally continued on the case-by-case basis, if the dose in the area surrounding the residential area was still relatively high after
the ongoing decontamination work is finished over relatively wide areas.
Area B (Forest users and workers enter on a daily basis)
・For bed log laying yard, if the continuation and restarting of cultivation are expected, it is permitted to remove the accumulated organic matter,such as fallen leaves, in the cultivated land and in the area in the reach of about 20m of its surrounding, according to the decontamination methodof forest in area A,
Area C (forest except area A and B)
・The Ministry of Environment takes a new approach based on the indications concerning the possible outflow of radioactive materials to the living
area from the area where understory vegetation is decline partially weathering.
・In the Forestry Agency, a demonstration project is advanced from the point of view of forest regeneration to the decontamination of the forest where
it is located outside of the living area and forestry was carried out, while dealing with radioactive materials.

Figure 1-12 Future direction of decontamination works in forests45 .
In the meantime, the policy for rivers and lakes was also announced. Previously, due to the shielding
effect of water, the existence of inflow sediment from the land, and the movement within the watersheds, it
was planned to study measures after accumulating investigation results and research while conducting
regular monitoring. In August 2014, the MOE announced the “summary of concept in the future measures
for rivers and lakes”. It stated that “the decontamination should be made as needed in the living zones withmany public activities and with high dose rate due to accumulation of radioactive cesium, when water isdried up and no shielding effect is expected”.
In October 2013, when the “Comprehensive review results of the progress of decontamination” wasannounced, as a follow-up to the IAEA international mission two years earlier, the IAEA follow-up mission
team visited to confirm the progress of the situation and to compile recommendations as given below.

(September 2013)
45Source: Forestry Agency: "Forest /forestry white paper in fiscal year 2013" (May 30, 2014)22

Examples of thirteen highlights of important progress and recommendations on eight
points which were shown in the “Final Report: The Follow-up IAEA International
Mission on Remediation of Large Contaminated Areas Off-Site the Fukushima Daiichi
Nuclear Power Plant”46,47【Examples of thirteen highlights of important progress】
The Team acknowledges the institutional arrangements implemented by Japan to address theremediation needs of the areas affected by TEPCO’s Fukushima Daiichi NPP accident. The Teamappreciates that Japan makes enormous efforts to implement the remediation programme inorder to reduce exposures to people in the affected areas, to enable, stimulate and support thereturn of people evacuated after the accident, and to support the affected municipalities inovercoming economic and social disruptions. The review Team recognizes the involvement of awide range of ministries and agencies, as well as institutions of the municipalities, to support
remediation by providing financial resources, technical guidance and institutional assistance.
The Team welcomes the critical evaluation of the efficiency of the removal of contaminatedmaterial compared with the reduction in dose rate offered by different methods ofdecontamination, recognizing that this is an important tool in the application of decontamination
methods. In addition, the Team notes a welcome change from guiding remediation efforts basedon surface contamination reduction, to a reduction in air dose rates. This is leading somemunicipalities to conclude that an additional 1 mSv per year is more applicable to long-term dose
reduction goals.
The Mission Team found significant progress in the development and implementation of
temporary storage facilities by municipalities and the National Government for contaminatedmaterials generated by on-going remediation activities. In addition, the Mission Team notes the
progress made towards the establishment of interim storage facilities by the National
Government with the cooperation of municipalities and local communities.

【Examples of recommendations on eight points】
Japanese institutions are encouraged to increase efforts to communicate that in remediation
situations, any level of individual radiation dose in the range of 1 to 20 mSv per year is
acceptable and in line with the international standards and with the recommendations from therelevant international organisations, e.g. ICRP, IAEA, UNSCEAR and WHO. The appropriate
application of the optimisation principle in a remediation strategy, and its practicalimplementation, requires a balance of all factors that influence the situation, with the aim ofobtaining the maximum benefit for the health and safety of the people affected. These facts haveto be considered in communication with the public, in order to achieve a more realistic perceptionof radiation and related risks among the population. The Government should strengthen its
efforts to explain to the public that an additional individual dose of 1 mSv per year is a long-term
goal, and that it cannot be achieved in a short time, e.g. solely by decontamination work. A
step-by-step approach should be taken towards achieving this long-term goal. The benefits ofthis strategy, which would allow resources to be reallocated to the recovery of essential
infrastructure to enhance living conditions, should be carefully communicated to the public. The
IAEA – and very likely also the international scientific community – is ready to support Japan inthis challenging task.

（9） The start of lifting of evacuation orders associated with the completion of full-scaledecontamination and other progresses, and follow-up decontamination
In April 2014, after the completion of full-scale decontamination in June 2013, theevacuation order was lifted on the Special Decontamination Area in Tamura City. On theother hand, in July 2014, the decontamination implementation plan was finally formulated in
Futaba Town, where the formulation had been delayed the longest. As a result, formulations
46Source: IAEA “Final Report: The Follow-up IAEA International Mission on Remediation of Large

Contaminated Areas Off-Site the Fukushima Daiichi Nuclear Power Plant” (January 23, 2014)（http://www.env.go.jp/press/file_view.php?serial=23734&hou_id=17656）
47Source: Excerpt from the draft translation (summary portion only) of the IAEA ”Final Report: The
Follow-up IAEA International Mission on Remediation of Large Contaminated Areas Off-Site the
Fukushima Daiichi Nuclear Power Plant " (January 23, 2014)23

of the decontamination plans in all municipalities in the Special Decontamination Area werecompleted (except areas where it was expected that residents will face difficulties in returning
for a long time), and decontamination and measures toward the lifting of the evacuation order
have been implemented.
The effects of the decontamination operations are reviewed by the post-monitoring to be
conducted at six to twelve months after the initial decontamination operations. If there areplaces with erosion of effectiveness of decontamination, the investigation will be conducted to
identify the cause as much as possible according to the individual situation. Then, by judging
the rationality and feasibility, the follow-up decontamination operations will be
implemented48.

1.1.3. Overview of the change of the evacuation area designation
As mentioned in 1.1.2, the designation of the evacuation areas was changed several times (Figure 1-13).
The outline of each evacuation area and the background to the modification of the designated areas areindicated here.
As of April 22, 2011
(At the time of completion of area setting
just after the accident)

August 2013
(At the time of review completion of area
setting)

As of October, 2014

Evacuation area map
As of October 1, 2014
LegendDifficult-to-return area
Residence restricted area
Evacuation order lifting
preparation area

Date City
Date City
Iitate Village

Iitate Village

Date City

Emergency
Deliberate
evacuation
Kawamata Town
evacuation area preparationarea
Kawamata Town

Minamisoma City
Iitate Village
Minamisoma City
Kawamata Town

Katsurao Village

Katsurao Village

Namie Town
Tamura City

Emergency
evacuation
preparation area

Namie Town
Futaba Town
Tamura City

Okuma Town

Okuma Town

Tomioka Town

Kawauchi Village

LegendNaraha Town

Ono Town

Katsurao Village

Restricted area

20km
Hirono Town

Fukushima
Daiichi Nuclear
Power Plant

Residence restricted area
Evacuation order lifting
preparation area

Futaba Town Fukushima

Daiichi Nuclear

Okuma Town Power Plant

Tomioka Town

Difficult-to-return area

Tamura City

Namie Town

Kawauchi Village Tomioka Town
Fukushima
Daini Nuclear
Power Plant

Fukushima
Daini Nuclear
Power Plant

Naraha Town

Naraha Town
Hirono Town

30km

Hirono Town

Figure 1-13 Change of the evacuation areas49 .

（1） Setting of the evacuation area and indoor evacuation area
In order to ensure the health and safety of the residents in the region around the FNPS,
based on the situation of the reactors, the NERH directed the Fukushima Governor and theMayors of other relevant municipalities to instruct their residents to evacuate or to shelterindoors, based on the "Act on Special Measures Concerning Nuclear Emergency
Preparedness" (hereinafter referred to as the Nuclear Emergency Preparedness Act). (Thedirections on sheltering were lifted on April 22, 2011.)

48Source: The 11th Environmental Remediation Study Meeting Material: Follow-up decontamination (March

20, 2014)

49Source: Ministry of Environment (MOE), Evacuation area maps created based on the document of the“Government Nuclear Disaster Victims Life Support Team”24

It should be noted that for the TEPCO’s 2FNPS the risk of a serious accident occurrence
decreased to a considerable degree in comparison with the situation on March 12, 2011 when
the nuclear emergency had been declared. Therefore, the evacuation area which had been set
as the area within the radius of 10 km from the 2FNPS was changed to the area within theradius of 8 km on April 21, 2011.

（2） Setting of the restricted area, deliberate evacuation area, and emergency evacuation
preparation area
In order to ensure smooth evacuation of residents step-by-step, besides the restricted area and deliberate
evacuation area, an emergency evacuation preparation area was set to deal with any future emergency.

1）Restricted area
In order to ensure the safety of the residents, the NERH announced to the Fukushima Governor and theMayors of other relevant municipalities that it set the area within the radius of 20 km from TEPCO’s
1FNPS as the restricted area based on the Nuclear Emergency Act (April 21, 2011). According to this
instruction, nobody, except those who were engaged in the emergency response measures, including such
public officials as firefighters, police officers, maritime officers, and self-defense force personnel, has anaccess to the area without the permission of the mayors after 00:00 on April 22, 2011.

2）Deliberate evacuation area
The NERH set the areas where the cumulative dose during the period of one year after the 1FNPS
accident might reach 20 mSv as the “deliberate evacuation area,” where evacuation to outside the area was
required for residents within roughly 1 month, in consideration of the impact on their health (April 22,2011).

3）Emergency evacuation preparation area
The NREH lifted the direction of indoor evacuation in the area within the radius of 20 km and 30 km
from TEPCO’s 1FNPS. On the other hand, under the accident situation which has not yet been stabilized,
there were some areas where the need for such refuge could not be excluded in an emergency. The NERH
designated such areas as the “emergency evacuation preparation area,” where the residents are required toprepare for being able to evacuate indoors or to take refuge in an emergency (April 22, 2011).

（3） Rezoning through lifting and reviewing of former designations
The NERH announced the concept for the review of the evacuation area. The announcement stated theevacuation orders had substantial impact on the lives of residents and it would be appropriate to review theevacuation orders, once a significant change occurred in the situation, for example, the verification ofsafety of nuclear reactor facilities was made or the reduction of dose was confirmed on the basis ofcontinued monitoring. It was decided that the evacuation area would be reviewed, revised and set as the
new evacuation designated areas according to their perspectives of recovery and reconstruction, based on
the results of radiation monitoring and the safety evaluation of the reactors and other factors,.

1）Lifting of the designation of emergency evacuation preparation area
Concerning the emergency evacuation-preparation area, which the NERH had designated between theradius of 20 km and 30 km from 1FNPS as the area where emergency responses such as evacuation might25

be requested in an emergency, the NERH decided the policy50 (August 9, 2011) when to lift thedesignation The policy dictated that the designation should be lifted when the following conditions become
foreseeable; safety evaluation of the nuclear power station, radiation monitoring results in detail in the area,
and restoration of public services and infrastructures in the area.
Based on this policy, the relevant municipalities started the development of their own “recovery plans”
according to their respective circumstances, in which the intentions of the residents were sufficiently
reflected and cooperation with the prefecture was taken into account. Each plan included support of theresidents’ smooth resettlement, reopening of public services such as schools and medical facilities,
restoration of public infrastructure, and, decontamination of school grounds and parks. At the stage when
the development of the individual plans was completed, the NERH decided to lift the designation of theemergency evacuation preparation area collectively and notified the relevant municipalities (September 30,2011).

2）Reviewing of restricted area and evacuation area
Based on the recognition of termination of the accident at TEPCO’s 1FNPS and the reduction in the riskof radiation exposure, the NERH decided a policy to lift the designation of the restricted areas (the areas
within the radius of 20 km from the nuclear power station) progressively, after making safety checks andcompleting the emergency restoration of infrastructures, and also after coordinating among the persons
concerned for disaster prevention and crime prevention measures, etc. In addition, for the evacuation areas(the restricted areas within the radius of 20 km, and the deliberate evacuation areas located beyond theradius of 20 km from the nuclear power station), it was decided to review those areas and to classify theminto three new areas cited below as shown in Figure 1-14, based on the radiation dose rates in those areas,
and after having discussions with the persons concerned (December 26, 2011). It is noted that the various
kinds of limitations were mitigated especially in the areas in which evacuation orders are being prepared
for lifting (the evacuation order lifting preparation area) as shown in Table 1-2.

Difficult-to-return area

Areas where annual cumulative dose might not be yet lessthan 20mSv even after five years

Residence restricted area

Areas where annual cumulative dose might exceed 20mSv
Distributionof the annual
cumulative
dose obtainedby correcting
the result of
the fourth
airborne
monitoring
survey to thepoint of
March 31,

Evacuation order lifting
preparation area

Figure 1-14 Review of the categories of evacuation areas into three designated areas based on
the annual cumulative dose estimated from air dose51 .
50Source: Nuclear Emergency Response Headquarters (NERH), "The basic concept on the review of

evacuation areas" (August 9, 2011)

51Source: Cabinet Office, "Review of the Evacuation Area" (October 2013) (Table 1-2 also the same source)

26

Areas in which evacuation orders are being prepared for lifting (hereinafter referred to“Evacuation order lifting preparation area”)

The evacuation order lifting preparation area refers to the area where it was confirmed that the annual
cumulative dose would not exceed 20 mSv in the evacuation areas as of December 26, 2011. In those areas,
the evacuation orders are still continued, but the supporting measures for recovery and reconstruction, suchas decontamination, infrastructure restoration, employment promotion, should be taken quickly, andresidents’ return as soon as possible should be the aim.
It is noted that the evacuation orders will be lifted based on sufficient consultations with authorities ofthe prefecture and municipalities, and residents, under the condition that the infrastructures indispensable todaily life are almost restored, such as electricity, gas, water and sewerage systems, main transportation
networks, and postal and communication services, and the life-related services including medical andnursing care, and at the stage in which the decontamination works mainly for the living environment ofchildren are progressed sufficiently.
When lifting the evacuation order, the circumstances of each municipality have to be consideredsufficiently. Therefore, the evacuation order should be lifted, not simultaneously in the whole area, butwhen each relevant municipality considers individually most appropriate. It can be also lifted step-by-stepeven within one municipality.
Areas in which residents are not permitted to reside (hereinafter referred to as the“Residence restricted area”)
The residence restricted area refers to the areas where the annual cumulative dose might exceed 20 mSv
among the evacuation areas as of December 26, 2011, and that subsequently require continued refuge fromthe viewpoint of reducing the dose of the residents. In those areas, decontamination works andinfrastructure restoration, etc. are carried out premeditatedly, aiming at the residents’ return andreconstructing of the community in the future.
In addition, it has been decided to shift those areas to the “evacuation order lifting preparation area,”
when it is confirmed that the annual cumulative dose that inhabitants receive will not exceed for sure 20
mSv due to the decontamination works and the natural decay of radioactive materials.
Areas where it is expected that the residents have difficulties in returning for a longtime (hereinafter referred to as the “Difficult-to-return area”)
The difficult-to-return area refers to the areas among the evacuation areas where the annual cumulative
dose might not be yet less than 20 mSv even after five years, and exceeds 50 mSv as of December 26, 2011.
According to the principle that the residence would be restricted in those areas for the future, it was decided
that the designation of those areas would not be reviewed for five years. However, even in that case,according to contamination level due to radioactive materials in the future, the contents of the planning forreconstruction and restoration in related municipalities and the situation of their implementation, it was
decided that the implementation of the review of those measures be considered.
It should be noted that the evacuation areas were reviewed and classified into three new designated areasusing air dose rates basically as mentioned above. However, the distribution of air dose rates is complicatedand is not uniform. Therefore, it was considered to be a basic principle from a practical viewpoint to avoid
division of a community and to set the whole of the administrative section unit as one area within the newly
classified areas, based on the dose level which occurs in most places within the administrative section unit.
Review of the evacuation areas was performed through coordination with the relevant local
municipalities and residents. The designation of the area classification is closely related to the timing ofreturn and the compensation. Therefore, there were some areas that needed much time for the adjustment.
As a result, it was not until August 2013 that the review of all evacuation areas was completed.

27

Table 1-2 Mitigation of the limits due to the review of the evacuation areas
After review
Beforereview

Difficult-to
Evacuation order
Residence-return
lifting
restricted area
area
preparation area

Change before and after
the review of areas

△

×

○

○

Accessible to home, etc.
(excluding thedifficult-to-returnareas) (Notes 1)

×

×

×

×

―

Special staying

×

×

○

○

Allowed to stay athome during certain
time-period(Notes 2)"Staying for the
preparations for the return
to hometown"

×

×

○

Permitted long-termstaying if certain
requirements are met.

Starting of new companies
and business activities(company invitations, etc.)

×

×

△

(Notes4)○(Notes5)

Allowed to invite newcompanies

Reoperation of existing
companies and businesses

×

×

△

○

(Notes4)(Notes5)

Farming/Forestry

×

×

△

(Notes6)(Notes6)

Access to area

Staying at home, etc.

＊Accessible
in deliberate
evacuationarea

A r e a c o ntr o lBudgetTax (forbusinesses)

Reconstruction restoration businesses

Living environment
improvementbusinesses

×

Return andrestoration
acceleration business(Notes3)×○○(Notes7)(Notes7)

○

○

―

○

○

○

Special depreciation,etc., or tax credits tocapital investment

×

×

○

○

Tax credit for salaries
to employees

×

×

○

○

Permitted reoperationof the existing
businesses
Permitted restarting ina part of the evacuation
areas

Acceleration ofreconstruction andrestoration businesses

Realization of thetreated well businessenvironment (except
for return difficult
areas)(Note 1) Allowed temporary access to the residence restricted areas and evacuation order lifting preparation
areas within the extent that municipalities recognize this. A year-round open system (temporary
access to those areas once every month (Except for January and April) on the day when inhabitantshope) is being conducted in Okuma Town, Tomioka Town, Namie Town and Futaba Town.
(Note 2) It is possible to stay overnight during a certain period of time, based on application to authorities ofthe municipalities and after the confirmation of the nuclear disaster site headquarters. The total
number of residents to stay overnight was 1,870 in New Year, Golden Week and Spring and Autumn
Equinox Festivals (implemented municipalities: Kawauchi Village, Tamura City, Minami-soma City,
Iitate Village, Katsurao Village and Kawamata Town).
(Note 3) In principle, the long-term staying applies to the evacuation order lifting preparation areas. Even in
residence restricted areas, if the requirements are met, on the basis of consultation with the chiefs ofmunicipalities and the head of nuclear disaster site response headquarters, long-term staying ispermitted.
(Note 4) For the businesses that are indispensable in the restoration and reconstruction and recognizedexceptionally, and the businesses that are not intended for residents (financial institutions, waste
disposal treatment facilities, gas stations, manufacturing industries, etc.), it is possible to start thebusiness operations after passing through the predetermined procedures.
(Note 5) As a general rule, the starting of the business to target the residents is impossible. However, forhospitals, welfare nursing facilities, restaurant businesses, retail trade and services, etc., thestarting of the preparation works for implementation of businesses such as new construction andrepair of facilities, receiving of materials and equipment, and inventory control, is possible.
(Note 6) Farming in the evacuation order lifting preparation area can be restarted based on the planting
restrictions of rice and the status of decontamination. On the other hand, in the residence restricted
areas, it is possible to carry out the maintenance and management of agricultural lands. It is also
possible to carry out the planting demonstration projects etc., aiming at restart of farming in thoseareas, which are performed under the participation of public organizations of municipalities.
(Note 7) Living environment improvement businesses are limited only if those are deemed necessary forreconstruction and restoration toward the designation of the evacuation order lifting preparation area.

28

1.1.4. Outline of the Act on Special Measures Concerning the Handling of Environmental
Pollution by Radioactive Materials Discharged by the Nuclear Power Station Accident
Associated with the Tohoku District-Off the Pacific Ocean Earthquake that Occurred on March
11, 2011（1） Act on Special Measures
1）The point of the Act on Special Measures
This Act was established to address the urgent issue of reducing promptly the impact of environmental
contamination on human health and the living environment caused by radioactive materials, which had
been released by the nuclear power plant accident associated with the Great East Japan Earthquake. It
defines that the basic principles regarding the handling of the environment pollution caused by radioactive
materials are determined in a cabinet meeting, and that the monitoring and measurement are carried out todetermine the status of the environmental contamination by accident-derived radioactive materials. It also
sets the matters relating to the disposal of wastes and the matters on measures for decontamination of soil,
etc. contaminated by radioactive materials.

2）The Basic Principles under the Act
The Basic Principles under the Act provide a decontamination framework and were approved in the
Cabinet meeting on November 11, 2011.
The following goals have been established in the Basic Principles.
The areas where the annual additional exposure dose exceeds 20 mSv are aimed to be
reduced in size step-by-step but as quickly as possible. However, it is necessary to note thata long-term approach is required for the areas where the radiation exposure dose isparticularly high.
The specific decontamination goals in these areas shall be set in the future based on theeffect of decontamination measures of soil and wastes, the results of demonstration model
projects and other development.
For the areas where the annual additional exposure dose is below 20 mSv, the following
goals are set.
The annual additional exposure dose decreases to 1 mSv/y or less in the long-term.
The annual additional exposure dose of the general public is reduced by about 50%
by the end of August 2013 as compared with that at the end of August 2011, by
including physical attenuation of radioactive materials and other factors..
It is important to restore the environment where children can live without fear.
Therefore, the goal is set to reduce the annual additional exposure dose of children
by about 60% by the end of August 2013 as compared with that at the end of
August 2011, by decontaminating their living environment such as schools andparks in high priority and including physical attenuation of radioactive materials..

These goals will be reviewed appropriately based on the effects of measures of the decontaminationof soil, etc.
In addition, for the Special Decontamination Area excluding the areas with particularly high additional
exposure dose, the schedule to complete the decontamination in those areas in approximately two years wasshown; “by the end of March 2014, measures for the decontamination of soil, etc., are carried out in
residences, offices, buildings of public facilities, roads, farmlands, forests around the living space, etc., andsoil removed by decontamination works is conveyed to the properly managed temporary storage sites one
after another”.
Further, for the areas with particularly high additional exposure dose, it was indicated that the National
Government should implement demonstration model projects first.
29

Basic Principles (Cabinet Decision 0n 11 November)
Establishment of implementation system by the Ministry of Environment and other relevant Office and Ministries ( 18 November)

Cabinet Orders and Ministerial Ordinances on requirements for the designation of areas, treatment standards, etc. (14 December promulgated)
Waste

Decontamination
Designation of Special Decontamination
Areas (Restricted Area and Deliberate
Evacuation Area)

Designation of Intensive Contamination
Survey Areas (Annual additional
exposure:1mSv or more)

Designation of Contaminated Waste
Management Areas (Restricted Area andDeliberate Evacuation Area)

Local systemestablished

Preceding decontamination by national gov.

Jan. 2012: the Act
came into full effectPreparation fordecontamination works under
the direct control of national
government.

Preparation bymunicipalities

Formulation of
Decontamination
Plan by national
government.

Formulation of
Decontamination
Plan by eachmunicipality

Formulationof Treatment
Plan bynational
government.

Designation of
Designated Waste(Over 8,000Bq/kg)

Securing temporarystorage sites

Launch of fullscale
decontamination
by national
government.
2015

Preparation for treatment under the directcontrol Of national government.

Launch of fullscale
decontamination
by municipalities

Treatment of the designatedwaste and the waste
generated in theManagement Areas bynational government.

Securing interim storage facility and starting to bring the waste from temporary storage sites in Fukushima Prefecture

Decontamination targets

Target for areas with less than 20mSv/ya. The annual additional exposure dose decreases to below 1 mSv in the long-term.

Target for areas with 20mSv or more in one
year
Reduce the size of the areas step-by-stepbut as soon as possible.

b. Reduce the annual additional exposure dose by about 50% by the end of August
2013, when compared with that at the end of August 2011.
c. Reduce the annual additional exposure dose of children by about 60% by the endof August 2013, when compared with that at the end of August 2011, bydecontaminating their living environment in high priority

Target for areas with 20mSv/y or more,

Target for the areas under the direct control of national gov. excluding the areas with particularly high annual additional exposure dose
By the end of March, 2014, the decontamination works are to be completed in residences, offices, buildings of public facilities,
roads, farmlands, forests around the living environment, etc., and soil removed by the decontamination works is conveyed to thetemporary storage sites one after another.

Figure 1-15 Outline of the Implementation of the Act on Special Measures52.

（2） Urgent implementation basic policy on decontamination
As indicated in 1.1.2.(4) 1), prior to the promulgation of the Act on Special Measures, the "Urgent
Implementation Basic Policy on Decontamination" was announced on August 26, 2011 by the NERH. In it,
the following five items were defined as the provisional targets in implementing the decontamination.

52 Document of Ministry of the Environment

30

(i)

Based on the 2007 basic recommendations of the International Commission on
Radiological Protection (ICRP) and the “basic concept” of the Japanese Nuclear
Safety Commission, the areas with the situation of emergency radiation
exposure (the annual additional exposure dose exceeds currently 20 mSv) are aimed
to be reduced in size step-by-step but as quickly as possible.

(ii) For the areas with the situation of existig exposure （the areas where the annual
additional exposure dose is 20 mSv/y or less), the aim is to reduce the annual
additional exposure dose to 1 mSv/y or less in the long term.
(iii) As a specific target of decontamination implementation in the areas contaminated byradioactive materials, it is aimed that the estimated annual exposure dose of thegeneral public be reduced by about 50% in two years.
According to the NERH provisional estimates, the estimated annual exposure dose
after two years will be reduced by about 40% compared with the estimated annual
exposure dose at present, by physical attenuation of radioactive materials and by
natural factors such as wind and rain (weathering effect).
By reducing at least approximately 10% of the exposure dose by decontamination
works, the above target of 50% reduction of the exposure dose will be achieved. In
addition, further reduction of exposure dose will be pursued.
(iv) It is important restore the environment where children who are more susceptible toradiation than adults can live in peace as before. Thus, it is aimed that the estimatedannual exposure dose of children be reduced by about 60% in two years throughthorough decontamination works in their living environment such as schools andparks.
According to the NERH provisional estimates, the estimated annual exposure dose ofchildren after two years will be reduced by about 40% compared with the estimatedannual exposure dose at present, by physical attenuation of radioactive materials
and by natural factors such as wind and rain (weathering effect).
By reducing at least approximately 20% of the exposure dose by decontamination
works, the above target of 60% reduction of the exposure dose will be achieved. In
addition, further reduction of exposure dose will be pursued.
(v) The targets mentioned above are the provisional targets being set based on limited
information in order to urgently implement the decontamination works. Thoseshould be examined and reviewed on a timely basis through detailed monitoring andaccumulation of data, survey of actual exposure dose of children, anddecontamination demonstration model projects.

In addition, the "Urgent Implementation Basic Policy on Decontamination" mentioned that for theachievement of these provisional targets, the National Government would continuously provide technicalinformation ("a technical catalogue") necessary for the decontamination works, including effective
decontamination methods, costs, precautions to make, which would be obtained through the demonstration
model projects and the approach how to proceed with decontamination of each area depending on the
difference in dose. The following four points were mentioned as the methods for "treatment of soil, etc.
produced by decontamination works".
(i)

The treatment of soil generated as a result of decontamination works, and rice straw,
compost and debris that exist in the region, are indispensable for the implementationof smooth and quick decontamination works.
(ii) For treating such soil and wastes, the National Government takes responsibility forsecuring of their disposal sites where long-term management is required, andensuring their safety. The National Government would publish a road map for theconstruction as quickly as possible.
31

(iii) However, in order to take these fundamental measures, time for securing anddevelopment of disposal sites of a certain size will be required. If we wait until suchdisposal sites are ready, it might delay quick decontamination.
(iv) Therefore, it is realistic for the time being that soil and wastes generated as a resultof decontamination works are stored in temporary storage sites in each municipality
or community. The National Government should continue all possible efforts to
support municipalities in financial and technical aspects.
The Basic Principles of the Act on Special Measures shown in 1.1.4 (1) 2), are intended to take over the"Urgent Implementation Basic Policy on Decontamination."（3） Prevention of radiation hazards due to decontamination works
The MHLW enforced the Ionizing Radiation Ordinance for Decontamination” on January 1,
2012, as a measure to reduce the radiation exposure dose of workers who were engaged insuch works as decontamination works (hereinafter referred to as "decontamination workers").
Then, in July 1, 2012, the Ionizing Radiation Ordinance for Decontamination was revised to
expand the applicable works in order to include the prevention of radiation hazards to theworkers who were engaged in restoration/reconstruction and related works.
The main features of the Ionizing Radiation Ordinance for Decontamination are given below. The
Ordinance is applied to the business operators for decontamination or works under a designated dose rate,
their employees engaged in decontamination or works, under a designated dose rate.
(1) Basic principles of prevention of radiation hazards(2) Limits and measurement of dose(3) Measures concerning the implementation of decontamination and related works(4) Prevention of contamination(5) Special education, medical examinations, and others
Further, the MHLW developed the following two guidelines in order to enable business operators andtheir workers to perform decontamination related works in accordance with the Ionizing Radiation
Ordinance for Decontamination.
Guidelines for the prevention of radiation hazards of workers engaged in decontamination
works, etc.
Guidelines for the prevention of radiation hazards of workers engaged in works under adesignated dose rate

These guidelines specify the items such as protection measures, medical examination offices and others.

1.1.5. Overview of the Special Decontamination Areas（1） Requirements and designated situations for the Special Decontamination Area
The Special Decontamination Area is specified according to the Act on Special Measures as the area
where the decontamination plans are developed by the MOE and the decontamination work is conductedunder the direct jurisdiction of the National Government. It basically corresponds to the areas that were therestricted area within the 20 km radius from the TEPCO 1FNPS and the areas that were the deliberate
evacuation area where the cumulative exposure dose for one year after the accident might exceed 20 mSv.
Specifically, as shown in Figure 1-16, the whole area of Naraha Town, Tomioka Town, Okuma Town,
Futaba Town, Namie Town, Katsurao Village and Iitate Village, and the areas that were restricted areas ordeliberate evacuation areas in Tamura City, Minami-soma City, Kawamata Town, and Kawauchi Village
correspond to the Special Decontamination Area.

32

Soma City

Date City

Iitate Village
Kawamata Town

Nihonmatsu City

Minamisoma City

Special decontamination area
Katsurao Village
Namie Town

Futaba Town

Tamura City

Okuma Town

Fukushima
DaiichiNuclearPower Plant

Tomioka Town
Kawauchi Village

Fukushima
Daini Nuclear
Power Plant

Ono Town
Naraha Town
Specialdecontamination area

Iwaki City

Hirono Town

Figure 1-16 Special Decontamination Area53 .

（2） Structure of the decontamination works in the Special Decontamination Area
The decontamination for the Special Decontamination Area was scheduled based on the following basic
policies. As shown in Figure 1-17, the decontamination implementation plans were developed at first by the
Minister of the Environment. Preliminary decontamination for municipality offices and infrastructure
facilities were conducted, while model projects were conducted by the Cabinet Office and the MOE, andthen, full-scale decontamination is performed. As shown in Figure 1-18, the decontamination works have tobe advanced while obtaining the landowners’ consents because it is necessary to enter people’s property to
conduct full-scale decontamination
It is also necessary to secure temporary storage sites because a large amount of removed soil andcontaminated wastes are generated as the decontamination works progress.

53Source: Ministry of the Environment (MOE), "Request for the cooperation for decontamination works"(February, 2012)33

January

February

March

Plan

Decontamination implementation planin special decontamination areas

Demonstration
model projects fordecontamination

Model projects by the Cabinet Office

Apri

May

June

July

after summer

High-dose areas (model project by the Ministry of Environment)＊ Lessons learnt are reflected at
any time

Government offices, community centersPrior
decontamination

Joban expressway (model project by the Ministry ofEnvironment), etc.
Infrastructure facilities such as water supply and seweragefacilities, etc.

Confirmation/grasp of stakeholders
Briefing session
for Residents

Radiation monitoring of structures, housing, etc
Full-scaledecontamination

Full-scaledecontamination

Surveying the condition of structures, housing, etc.
Reaching consensus with stakeholders
Schedule as agreed with stakeholders

Start of decontamination works
Receiving soil and wastes (at any
time)

Temporarystorage sites

Surveys, preparations and storage

DesignFigure 1-17 The short-term decontamination roadmap for Special Decontamination Area54.

Grasp of thecaretakers(owners) of
the land

60,000households
surveyResidents
briefing
session about
field surveys

Radiation
monitoring /Survey ofstructures,
housing, etc.
(field survey)

Decision of thedecontaminati
on method

Several tens of thousands ofhousing survey (5 months)

Agreement of theaccess to housing, etc.

Decontamination
works

Post radiation
monitoring

Completion/(Continuous
monitoring)

Ordered as meeting thecondition

Confirmation of
decontamination
method, Reachingconsensus withdecontamination

Report of the resultsof dose reductions

Communication with the caretakers (owners) of the land
Figure 1-18 Flow chart of the decontamination steps.

54Source: Ministry of the Environment (MOE), "Decontamination Policy for Special Decontamination Areas(Decontamination Roadmap)" (January 26, 2012)(Figure 1-18 through Figure 1-20)

34

In addition, the Special Decontamination Area is classified into three areas depending on the level of
exposure doses. Decontamination is due to start from the areas of the low exposure dose level, as shown in
Figure 1-19, because the difficulty differs depending on radiation levels. The targets of decontamination ineach area are as shown in Figure 1-20.

FY 2011

Full scale decontamination

January
Areas whichbecomeevacuation
order lifting
preparationarea(*)*Areas with
20mSv/y or
lessAreas whichbecomeresidence
restrictedarea(*)*Areas with
20mSv/y 50mSv/y・Technology
demonstration bymodel projects
・Priordecontamination ofmunicipal offices
・Monitoring dose
rates nearstructures
・Surveying thecondition of
structures
・Reaching consensus
with stakeholders＊Plan and
implementation
taking into accountsite specificfeatures of eachmunicipality

Areas whichbecome difficultto-return area(*)
*Areas morethan 50mSv/yTemporarystorage site

FY 2012
April

July

FY 2013

October

April

July

OctoberJanuary

Areas with 10 – 20mSv/y(Schools with 5 – 20mSv/y)Areas with 5 – 10mSv/yAreas with 1 – 5mSv/yAreas with 20 – 50mSv/yDecontamination works arestarted with meeting theconditions such as reaching of theagreement with residents andsecuring of the temporary storage
sites

Verification ofdose rate
reductions

Demonstration model projects

DesignJanuary

after FY 2014

Receiving and control
Surveys and preparations (schedule as agreed with local community)

Figure 1-19 Decontamination roadmap for each new evacuation order area.

35

○By around the end of this fiscal year, decontamination implementation plan for special decontamination areas will be developed.
Based on the plan, full-scale decontamination works should be performed.
○ Evacuation areas will be reviewed and classified into three new evacuation areas based on the level of air dose rate, anddecontamination will be implemented in cooperation with the perspectives of recovery and reconstruction.
○ The prospects for securing of the temporary storage sites, and the aspects of smooth securing of workers must be considered in
the plan.
○ Model projects and prior decontamination are carried out parallel. The knowledge obtained through them is reflected
appropriately .

Policy for full-scale decontamination
Areas which become evacuation order lifting preparation area(*) *Areas with 20mSv/y or less・By around the end of 2012, aiming for the decontamination of the areas with 10 ~ 20mSv / y (Schools, etc.
with 5 – 20mSv/y(1- 4μSv/h))・By around the end of March, 2013, aiming for the decontamination of the areas with 5 ~ 10mSv / y.
・By around the end of March, 2014, aiming for the decontamination of the areas with 1 ~ 5mSv / y.
・Specific targets in the areas are reflected in the plan, taking also into account the results of the model projects.
・Aiming to less than 10mSv / y for the areas with 10mSv / y or more for the time being.
Aiming at 1μSv/h or less for schools, which is a criteria of the reopening of the schools.
Areas which become residence restricted area(*) *Areas with 20mSv/y - 50mSv/y・Aiming at decontamination from FY2012 to FY2013.
・Aiming at the reduction of the size of the areas step-by-step but as soon as possible.
Areas which become difficult-to-return area (*) *Areas more than 50mSv/y・Carrying out model projects for the time being.

Implementation policies andtargets of the specificdecontamination for eachmunicipality are developed
flexibly in coordination withstakeholders.

Main steps of the full-scaledecontamination④Radiation monitoring/Surveying the condition of
structures, housing, etc.
⑤Reaching consensus for decontamination with caretakers⑥Implementation of decontamination works①Grasp of the caretakers (owners) of the land to be
decontaminated②Briefing session for Residents③Agreement of the access to housing, etc.

The development of the contents of this road map is planned and is utilized in planning and project
implementation in future

Figure 1-20 Points for the policy on the decontamination in the Special Decontamination Area.

Along with these decontamination framework in the Special Decontamination Area, the MOE carried out
detailed monitoring from November 7, 2011 through February 28, 2012, in the areas where the National
Government should perform decontamination, and the air dose rate distribution was clarified to some extent
based on the measurement results.
The Government also carried out decontamination model projects (see 1.1.6 for details), collected
knowledge about the decontamination, and then developed the common specifications of decontamination
works (“Common Specifications”) for the National Government to order decontamination works.
Furthermore, the MOE held residents’ briefing sessions prior to performing preliminary decontamination
works, and acquired the agreement of the residents before carrying out major decontamination works. At
the stage when preparations for ordering of the decontamination works had been completed, the MOE
ordered decontamination works using the Common Specifications for decontamination works.
It should be noted that not only the provision of education to decontamination workers but also theproper management of the decontamination works are important because of the large-scale of thedecontamination works. Thus, various efforts were being taken for decontamination works (See Chapter 4
for details).

（3） Review of decontamination implementation plans in the Special Decontamination Area
In the middle of fiscal year 2013 that is the last fiscal year of the original decontamination work period inSpecial Decontamination Areas, the MOE performed the “comprehensive check and review of the progressof decontamination works” (those findings were announced on September 10, 2013). The MOE discussed
future decontamination plans with each municipality based on these results, and revised thedecontamination implementation plans in the Special Decontamination Area to more realistic ones based on36Article 29, Clause 1 of the Act on Special Measures,. The outline is indicated below.

1）Outline of the comprehensive check and review
The original target schedule, in which all the decontamination works had been planned
to be completed and the wastes and soil to be transferred to temporary storage sites
without exception within two years (by the end of March, 2014), should be revised toallow a flexible decontamination schedule in accordance with the situation of eachmunicipality and progress of restoration.
At that time, the measures to accelerate decontamination and to progress smoothly
should be taken, and decontamination plans should be reviewed flexibly according to
the progress of reconstruction.
In Tamura City, decontamination works were completed in accordance with thedecontamination implementation plan. In Naraha Village, Kawauchi Village andOkuma Town, decontamination works are aimed at completion in the fiscal year 2013in accordance with the current plans and schedules. For Minami-soma City, Iitate
Village, Kawamata Town, Katsurao Village, Namie Town and Tomioka Town, the MOE
continues to coordinate planning with each municipality and will revise the current
plans and schedule of works within the year. For Futaba Town, the development of thedecontamination plan will be continued in coordination with reconstruction measuresand the situation of the town.

2）Overview of the review of the plan
For Minami-soma City, Iitate Village, Kawamata Town, Katsurao Village, Namie Town,
and Tomioka Town, the comprehensive check and review in September decided torevise their decontamination plans by around the end of 2013. The revised realisticschedules are to be established through the consultation with each community
concerned in view of current situations.
Priority is to be placed on the decontamination of residential land and its neighborhood
which is important for the residents' return. The implementation schedules of thedecontamination works in each of the municipalities are shown in Table 1-3.
Infrastructures, such as water supply, sewage systems and major roads should be
decontaminated in advance in line with the progress of reconstruction activities bycoordinating with related organizations.
In implementing the projects, measures shall be taken to accelerate and advance thedecontamination more smoothly, and to shorten the work period to the extent possible.
The project schedules shall be thoroughly managed and the progress of thedecontamination works shall be made transparent.
Based on these, the decontamination plans in the subject six municipalities have beenrevised.

37

Table 1-3 Revised decontamination schedules55
Minami-soma
City

The decontamination of residential land and its neighborhood isprioritized, aiming to be completed in the fiscal year 2015.
The decontamination works of other places aim to be completed in thefiscal year 2016. Furthermore, efforts are made to accelerate andadvance the decontamination more smoothly, and to shorten the work
period to the extent possible.

IitateVillage

The decontamination of residential land and its neighborhood isprioritized, aiming to be completed in the fiscal year 2014.
Furthermore, efforts are made to accelerate and advance thedecontamination more smoothly, and to shorten the work period to theextent possible, aiming at the completion by the end of the year 2014.
The decontamination works of other places aim to be completed in thefiscal year 2016. Furthermore, efforts are made to accelerate andadvance the decontamination more smoothly, and to shorten the work
period to the extent possible, aiming at the completion by the end of theyear 2016.

Kawamata
Town

The decontamination of residential land and its neighborhood isprioritized, aiming to be completed in the fiscal year 2014.
Furthermore, efforts are made to accelerate and advance thedecontamination more smoothly, and to shorten the work period to theextent possible, aiming at the completion in the summer of 2014.
The decontamination works of other places aim to be completed in thefiscal year 2015. Furthermore, efforts are made to accelerate andadvance the decontamination more smoothly, and to shorten the work
period to the extent possible, aiming at the completion by the end of theyear 2015.

Katsurao
Village

The decontamination of residential land and its neighborhood isprioritized, aiming to be completed in the fiscal year 2014.
Furthermore, efforts are made to accelerate and advance thedecontamination more smoothly, and to shorten the work period to theextent possible, aiming at the completion in the summer of 2014.
The decontamination works of other places aim to be completed in thefiscal year 2015. Furthermore, efforts are made to accelerate andadvance the decontamination more smoothly, and to shorten the work
period to the extent possible, aiming at the completion by the end of theyear 2015.

Namie
Town

The area-wide decontamination in the decontamination designatedareas except for the tsunami disaster areas (Minamitanashio,
Ukedokita, Ukedominami, Nakahama, Morotake) is prioritized, aiming
to be completed in the fiscal year 2015.
While taking into consideration the treatment status of disaster wastes
in the tsunami disaster areas, the decontamination of residential land
and its neighborhood is prioritized, aiming to be completed in the fiscal
year 2015. The decontamination works of other places aim to becompleted in the fiscal year 2016. Furthermore, efforts are made toaccelerate and advance the decontamination more smoothly, and to
shorten the work period to the extent possible.

TomiokaTown

The decontamination of residential land and its neighborhood isprioritized, aiming to be completed in the fiscal year 2015.
The decontamination works of other places aim to be completed in thefiscal year 2016. Furthermore, efforts are made to accelerate andadvance the decontamination more smoothly, and to shorten the work
period to the extent possible.

FutabaTown

Coordination shall be continued for the development of thedecontamination plan, taking into account the results of model projects,
picture of reconstruction plan, and the level of radiation dose, etc.

※For implementation of the decontamination works, developing the decontamination plan, securing the temporarystorage sites, reaching agreement with land owners, and securing of workers are preconditions.

55Source: Ministry of the Environment (MOE), "Review of decontamination implementation plan in s"(December 2013)38

（4） Progress of the decontamination in the Special Decontamination Area
Figure 1-21 shows the decontamination status in the Special Decontamination Area as of March 2015.
Even in Futaba Town, where the schedule of decontamination works had been delayed, thedecontamination implementation plan was developed and decontamination works are due to start soon.
Meanwhile, in Tamura City and Kawauchi Town, decontamination works were completed, and all or part ofthe evacuation orders have been lifted.
Completion/Evacuation
order lifting
Completion
Started alreadyOrdered alreadyNot ordering

Residential land almost
completion; December,
2014

Tamura City
Kawauchi Village

Special decontamination area
Difficult-to-return area

Completion of area-wide decontamination works in March, 2014

Okuma Town

Completion of area-wide decontamination works in March, 2014

Katsurao Village
Kawamata Town
Iitate Village

Residential land
Completion； July,2015

Minamisouma City

Evacuation order lifting(evacuation order lifting
preparation area); October, 2014

Completion of decontamination works in June, 2013
(Opening between the Hirono IC - Joban Tomioka IC on February 22, 2014 )(Opening between the Namie IC - Minamisoma IC on December 6, 2014 )(Opening between the Namie IC - Joban Tomioka IC on March 1, 2015 )Completion of decontamination works for residential land in July, 2014
Aiming at the completion of the works for other places in the year 2015
Completion of decontamination works for residential land in August, 2014
Aiming at the completion of the works for other places in the year 2015
Aiming at the completion of decontamination works for residential land in thefiscal year 2015
Aiming at the completion of the works for other places in the year 2016
Aiming at the completion of decontamination works for residential land in thefiscal year 2015
Aiming at the completion of the works for other places in the year 2016

Namie Town

Aiming at the completion of decontamination works for the areas except for
the tsunami disaster areas in the fiscal year 2015
For the tsunami disaster areas, aiming at the completion of decontamination
works for residential land in the fiscal year 2015
and at the completion of the works for other places in the fiscal year 2016

Tomioka Town

Aiming at the completion of decontamination works for residential land in thefiscal year 2015
Aiming at the completion of the works forother places in the year 2016

Futaba Town

Aiming at the completion of decontamination works in the fiscal year 2015

Evacuation orderlifting; April, 2014
Area-wide
completion; March,
2014

Completion of area-wide decontamination works in March, 2014
Lifting of the evacuation order in evacuation order lifting preparation area on
October 1, 2014

Naraha Town

Joban Expressway

Residential land
completion; August,2014

Completion of area-wide decontamination works in June, 2013
Lifting of the evacuation order on April 1, 2014

Figure 1-21 Overview of the progress of decontamination works under the direct control of the
National Government (as of March 2015)56 .

56Source: Ministry of the Environment (MOE), Produced based on "Progress of decontamination works under

direct control of the National Government (as of March 2015)(https://josen.env.go.jp/material/pdf/josen_gareki_progress_201503.pdf)(Table 1-4 and Table1-5 are based on
the same source)

39

Table 1-4 Progress of decontamination works under the direct control of the National
Government (1) (As of February 20, 2015)

Tamura city

Area-wide completion;

Kawauchivillage

Naraha town

Okuma town

Residential land Completion

Katsurao village

Kawamata town

Progress of decontamination
Decontami(Other than the municipalities of the work
Schedule
Size ofnation areas
Review
Evacuation
completion; as of February 20, 2015)
decontami
Populationoforder
nationTemporary
Residential Other(people)areas Decontami
lifting
Agreement(ha) (round)storageWorks
landplaces(total)nation planacquisition
sites
completion completion
securedJune, 2013
FY2013 (already
April,
400
500
H24/4
H24/4
Acquired
already
completion
completed)20144
Evacuation
order lifting
March,
securedFY2013 (alreadypreparation
400
500
H24/4
H24/4
Acquired2014
already
completed)area;
completion
October,
2014
March,
securedFY2013 (already
7,700
2,100
H24/8
H24/4
Acquired2014
Undecidedalready
completed)completion
March,
securedFY2013 (already400
400
H24/12 H24/12
Acquired2014
Undecidedalready
completed)completion2014
securedAlmostsummer
1,400
1,700
H25/3
H24/9
Working
In 2015 Undecided
alreadyacquired(already
completed)
2014
About
Almostsummer
1,200
1,600
H25/8
H24/8
Working
In 2015 Undecided
90 %acquired(already
completed)Underworking/preparations

Iitate village

6,000

5,600

H24/7

H24/5

Minami-soma
city

13,300

6,100

H24/4

H24/4

Namie town

18,800

3,300

H25/4

H24/11

Tomioka town

11,300

2,800

H25/3

H25/6

Futaba town

300

200

H25/5

H26/7

40

securedalready

About
90 %

About
80 %
About
40 %
securedalready

About
70%
About
70%
About
90 %

Adjusting Preparing

Working

In 2014(almostcompleted)In 2016

Undecided

Working

FY2015FY2016

Undecided

Working

FY2015FY2016 Undecided

Working

FY2015FY2016

Preparing

FY2015

Undecided
Undecided

Table 1-5 Progress of decontamination works under the direct control of the National
Government (2) (As of February 20, 2015) (unit :%)Naraha Kawauchi
Town
Village

IitateVillage

Kawamata Katsurao
Town
Village

100

100

100

100

100

25

100

18

100

100

100

100

100

100

38

100

56

100

100

100

100

100

100

24

100

4

100

100

100

100

68

100

100

100

99.9

100

100

100

32

100

100

100

7

100

8

100

34

100

2

Order rate

100

100

Implementation rate

100

Order rate

100

Implementation rate

Implementation rate

96

Namie
Town

Order rate

Order rate

100

Implementation rate

Implementation rate

100

Minami-soma Tomioka
City
Town

Order rate

Order rate

100

Implementation rate

Implementation rate

100

Order rate

Order rate

100

Implementation rate

Implementation rate

100

Okuma
Town

Order rate

Order rate

Residential
land
Farmland
ForestRoad

TamuraCity
Implementation rate

As of 20th
February,
2015

99.9

17

100

11

48

65

5

100

13

35

79

28

100

14

43

65

61

100

20

46

Note 1) Implementation rate is the percentage of the sizeof a completed series of decontamination
works (weeding, sediment removal, washing, etc.), to the size of decontamination objects in eachmunicipality.
Note 2) The order rate is the percentage of the contracted size to the size of decontamination
objects in each municipality.
Note 3) Size of decontamination objects, ordering size, and the size that ordering acts have been
finished may be changed with future surveys.

1.1.6. Overview of the demonstration model projects for decontamination
This section excerpts the outline of the report on the demonstration model projects for decontamination
prepared by the Cabinet Office57, which was positioned in the decontamination plans in the Special
Decontamination Area indicated in 1.1.5.(1).
Through these projects, knowledge and decontamination technologies were confirmed. In particular, thefollowing points were seen: the importance of monitoring to prevent any hot spot from being overlooked;
the importance of such obvious work environment preparations as procurement and supply of
decontamination-related goods including the securement of water supplies to push forward
decontamination works; the impact of winter weather on decontamination works; implementing effective
measures to maintain the quality of large-scale decontamination works; considering the possibility ofre-contamination; having effective strategies to prevent recontamination; and having effective measures toreduce the volume of wastes. Moreover, it was also necessary to understand the anxiety of residents todecontamination works and to make sure radiation protection for decontamination workers.
The results obtained in these projects are shown in the following (3) (4), and particularly important
findings are shown in (7).

（1） Objectives
The main objectives of the demonstration model projects for decontamination were to establish: themethods for efficient and effective decontamination; and the safety measures relating to radiation
protection of workers for the areas mainly with high radiation exposure dose in which the annual additional
exposure dose exceeds 20 mSv.
Specifically, an area of constant size for model project implementation was set in each of the 12
municipalities (Tamura City, Minami-soma City, Kawamata Town, Hirono Town, Naraha Town, Tomioka
Town, Kawauchi Village, Okuma Town, Namie Town, Katsurao Village, Iitate Village, and Futaba Town58)
belonging to restricted areas and deliberate evacuation areas. In those areas, the verification and theevaluation of the decontamination effect were carried out for the decontamination methods and57Source: Ministry of the Environment (MOE), "The overview report on the demonstration model projects fordecontamination in restricted areas and deliberate evacuation areas (Final revision)” (June, 2012)

58Futaba Town had also been included in the implementation areas of the model projects at first. However the

implementation has not been done because Futaba Town canceled the project.

41

technologies to be considered practical. And then, the data which would be utilized in the implementationof the future full-scale decontamination projects were acquired and prepared to be used immediately.
In addition, the results of these efforts were to be presented in the form of guidelines that could be usedas the reference sources by the National Government and local governments, etc. when performing
decontamination works.

（2） Implementation scheme and decontamination target areas
The target municipalities of the decontamination model projects for decontamination were divided into
three groups of A, B and C by JAEA, which was commissioned from the National Government for the
projects. In each group, Joint Ventures (JVs) performed the verification tests of decontamination
technologies based on their proposals for the decontamination submitted responding to the public call for
proposals by JAEA59.
Target areas in each group and decontamination targets are shown in Table 1-6.

59For the decontamination model project, Group A, Group B, Group C have been implemented by Taisei JV,

Kashima JV, and Obayashi JV, respectively.

42

Group A

Table 1-6 Target areas of the decontamination model projects in each municipality60
Decontamination target
Target areas for the(Total about 209 ha)Groups/Municipalities
decontamination model
projects
Main components/ features
Size
Kanebusa Elementary
Farmland, Building
Minami-Soma City
School and surrounding (Elementary School), Road, approx.
13ha
area
Forest, Residential land
Farmland, Road, Forest,
approx.
Kawamata Town
Sakashita area
Residential land
11ha
Building (Junior Highapprox.
Tsushima area
School, etc.), Road, Forest,
5ha
Residential land
Namie Town
Building (Station, Orbit,
approx.
Gongendo area
Library, etc.), Private
13ha
house, Farmland, Road
Kusano area
Building (Manufacture,
Iitate home, etc.),
approx.
Iitate Village
Base of “Patrol Team for Farmland, Private house,
17ha
Residential land, Road,
the Entire Iitate-mura”
ForestGroup B

Tamura City

Jikenjo area

Katsurao Village

Katsurao Municipal
Office and surroundingarea

Tomioka Town
Futaba Town
Hirono Town

Group C

Okuma Town

Yonomori Park
Tomioka Daini JuniorHigh School−
Chuo-dai/Nawashirogaearea

Okuma Municipal Officeand surrounding area
Ottozawa area

Naraha Town
Kawauchi Village

Kamishigeoka area
Minami Industrial
Complex
Kainosaka area

Farmland, Residential
land, Road, Forest
Farmland, Private house,
Residential land, Road,
Forest , Residential land,Road, Forest
Building (Junior HighSchool, Ground, etc.), Road
(row of cherry blossom
trees), Residential land,
Forest−Building (Government
Office, Elementary /JuniorHigh School,
Ground),Residential land,
Forest, Road
Building (Government
Office, Community Center,
Park),Residential land,
Road
Farmland, Residential
land, Road, Forest ,Farmland, Residential
land, Road, Forest
Building (Factory, etc.),
Road
Farmland, Private house,
Road, Forest

approx.
15ha
approx.
6ha
approx.
9ha
approx.
3ha−
approx.
33ha

approx.
6ha
approx.
17ha
approx.
4ha
approx.
37ha
approx.
23ha※1ha=10,000m2

60Source: Ministry of the Environment(MOE), "The overview report on the demonstration model projects fordecontamination in restricted areas and deliberate evacuation areas (Final revision)”, (June, 2012)43

（3） Overview of the results for decontamination targets
1）Residential landA) Deposition status of radioactive cesium
Large amount of radioactive cesium remain in the places where dust particles (soil) are
carried by rainwater and accumulated (such as gutters and rain spouts).
In addition, other than the places where rainwater accumulates, radioactive cesium tends
to be deposited on and remain in the soil surface layer of residential gardens, concrete slabs
on inclined surfaces, and asphalt surfaces.
Surface contamination levels of vertical outer walls, on which dust particles carried by
rainwater do not accumulate, are relatively low.
As a result of investigating the deposition and retention status of radioactive cesium fordifferent roof materials of houses (unglazed tiles, glaze tiles, cement roof tiles, galvanizediron), the largest amount of deposited radioactive cesium was for cement roof tiles. The
deterioration of the surface condition of the cement tiles is considered to have influenced
the deposition and retention.
The amount of deposited radioactive cesium was relatively small for galvanized iron andslate.
Moreover, radioactive cesium tended to be deposited and retained at specific spots on theroof.
Overlaying places of roof materials (such as tiles and galvanized iron)
Peeled portions of surface finishing (glazed or painted portions of roof tiles), rusted
or corroded portions of roof materials
Dirty areas or tree sap adhering points on the roof.
The portions of tiles to prevent snow from sliding off of a roof, such as snow guards
The dose rate of residential land was reduced overall by the decontamination works in theland. However it was found that the dose rate after the decontamination in the following
places had the tendency to be slightly higher than other places. Those places were theregions where the implementation of decontamination works was difficult, such as narrow
spaces, and around garden trees and other obstacles.

B) Decontamination methods and results
High decontamination effect could be achieved by forcefully removing most of the deposits
in gutters and then wiping off the remaining small deposits.
It was observed that the decontamination effect on a roof varied according to the materials.
Brushing with a deck brush was effective for unglazed tiles and painted ironplates.
Manually wiping the surface was also effective for unglazed tiles.
Coating release agent had a relatively high decontamination effect compared toother methods for slate or cement roof tiles.
For cement roof tiles, decontamination effect was limited in all decontamination
methods.
Decontamination of the roof with a coating release agent provided a certain degree of
decontamination and had a merit that it did not scatter the removed substances to thesurroundings. However, it required covering the surface to be decontaminated with aprotective material for 1-3 days and the temperature must be controlled inside the coveringin winter. Therefore, its usability was limited and it was generally not practical.
Decontamination of outer walls was carried out using the methods of "hand washing","wiping off ", "high pressure water washing", and "brushing" for each material of tin, sash,
glass, and wood. Even if the decontamination methods for outer walls were different, no big
difference was confirmed in the surface contamination density after decontamination.
Decontamination of gutters was performed using “wiping off” and “high-pressure watercleaning”. No significant difference was seen in their decontamination effects. “Wiping off”
had better usability from the fact that contaminated wash water was not scattered to thesurroundings.
Decontamination of concrete (earthen floors) was carried out using high pressure water44

washing. The effect of decontamination using high pressure water washing only was
limited. When a relatively small area was targeted in the decontamination, surface cuttingwith the dust collection sander was effective for decontamination. However, it was noteffective when a large area was targeted in decontamination, and it needed a dry surface
condition. In addition, even if other methods such as metal brushes were used together withhigh pressure water washing, their effect on decontamination did not change.
For gardens, the removal of gravel, etc. under rain gutters that had become hot spots had asignificant effect for decontamination.
It was found that air dose rates inside a building were reduced after the areas surrounding
the building, and the degree of dose reduction was almost the same indoors and outdoors
regardless of the material of the building (a concrete or a wooden building). Thus, in orderto aim at reduction of indoor radiation level, decontamination of the area around thebuilding is important.

2）Large buildingsA) Deposition status of radioactive cesium
Large amounts of radioactive cesium remain in places where dust particles, which were
deposited on large buildings, have been carried by rainwater and accumulated in certain
areas (such as gutters and rainspouts). On the contrary, the amount of radioactive cesium
was relatively small in the places where dust particles were just carried by rainwater anddid not accumulate.
It was confirmed that the radiation doses were higher in the places where dust particles
were accumulated, or moss was growing, or in the drainage paths of rainwater, than those
doses in their surrounding areas.
Surface contamination levels of vertical walls of large buildings, on which dust particles
carried by rainwater did not accumulate, tended to be low compared with those of concreteslabs on inclined surfaces or asphalt surfaces. On the other hand, contaminated verticalwalls were also observed according to the movements of raindrops.

B) Decontamination methods and results
The high-pressure water washing was effective for the decontamination of concrete roof
with waterproofing.
For the roof of concrete (mortar), decontamination effect was limited in all methods of “highpressure water washing (about 10 MPa)”, “high pressure water washing and brushing”,“nano-bubble washing”, and “special solution washing such as by oxygenated water”.
The decontamination of outer walls was carried out using the methods of "wiping off " and"high pressure water washing" for each material of tin, sash, glass, and wood. Even if thedecontamination methods of the outer walls were different, no big difference was confirmedin the surface contamination density after decontamination.
“Wiping off” has better usability at a point from the fact that contaminated wash water is
not scattered to the surroundings.
It was found that the decontamination effect outside a building had influenced in reducing
the air dose rates inside. This is considered to be due to reduced radiation from theradioactive materials outside which had been detected inside.

3）FarmlandA) Deposition status of radioactive cesium
In most cases, 80% or more of the radioactive cesium inventory was present in the surface
soil layer down to a depth of about 5 cm.
It was observed that radioactive cesium penetration depth was deeper in the fields that had
been plowed just before the accident.
No remarkable difference was seen in the tendency for deposition and retention ofradioactive cesium among rice fields, crop fields and orchards.

45B) Decontamination methods and results
An effective approach involves confirming the depth distribution of radioactive cesium;
determining the practical depth and efficiency of dose reduction methods of mixed tillage,
reversal tillage, interchanging topsoil with subsoil, or topsoil stripping; and performing themost effective reduction method.
In addition, the magnitude of dose reduction efficiency was approximately in the order of"mixed tillage <reversal tillage < (or =) interchanging topsoil with subsoil ≒ topsoil
stripping".
On the other hand, the amount of removed soil was in the order of "mixed tillage ≒reversal tillage ≒ interchanging topsoil with subsoil << topsoil stripping".
The effectiveness in dose reduction by reversal tillage or interchanging topsoil with subsoil,
which does not produce soil for removal, was equivalent to that by topsoil stripping.

4）Roads
A) Deposition status of radioactive cesium
Roads (paved) tended to have low air dose rates compared with soil surface of thesurrounding farmland and bare ground, etc. This is believed due to the fact that radioactive
materials deposited on the paved surface of the roads were washed away by rainfalls after
the accident.
Depth distribution of the surface contamination density of asphalt paved surfaces inhigh-dose areas has been measured. As a result, it became clear that most of the radioactive
materials remained down to a depth around 2-3 mm from the surface for pavement face ofdense grain-size, and down to a depth around 5 mm from the surface even for porous
asphalt pavement (permeable pavements, etc.).
From the relationship between the surface dose rate and surface contamination density, thevalue of the surface contamination density may be relatively high on some roads (paved
surfaces). Radioactive cesium is unevenly distributed near the pavement surface incomparison with the soil surface of the surrounding farmland and bare ground. Thus, it isconsidered that the contribution to the surface contamination density by beta ray having ashort range distance in solids is remarkable. This also corresponds to the distribution in thedepth direction of the contamination density of radioactive materials.

B) Decontamination methods and results
As decontamination methods for paved roads, "stripping-off" had a large efficiency of dose
reduction, but generated larger quantities of removed wastes compared with other methods.
Most of the inventory of radioactive materials was found to be present in a surface layer ofasphalt, down to a depth of a few millimeters. Thus, it is possible to achieve a highdecontamination effect, while minimizing the volume of wastes generated, by surface
shaving off only this thickness.
In comparison with "stripping-off (surface removal)", "washing" has the advantage that it
does not generate wastes as in the case of surface removal or surface stripping-off. However,
the efficiency of dose reduction is not high, and the collection and disposal of wash water arenecessary.
For asphalt paved surfaces, decontamination by "surface stripping-off or surface removal(water jet, shot blasting, TS cutting machine61, etc.)" was more effective than "cleaning (dryroad sweeping, etc.)" and "washing (high-pressure washing or use of vehicles for functional
recovery, etc.)""Surface stripping-off or surface removal" methods require machines and are difficult to be
applied to areas in the vicinity of buildings and outer walls. Irregularities in the effect ofdose reduction occurred for the roads with distorted and worn surfaces.

61These were road surface cutting machines that scrape off asphalt paving or concrete paving by a rotary

blade.

465）Parks and playing grounds
A) Deposition status of radioactive cesium
The tendency was observed that more than 80% of the radioactive cesium deposited within
the depth around 5 cm from the surface in most places.
The tendency was strong that radioactive cesium deposited and remained in degradedrubber playground equipment and rusted metal playground equipment. On the other hand,
the tendency that radioactive cesium deposited and remained in metal playgroundequipment with a smooth surface was weak.

B) Decontamination methods and results
Wiping was effective in dose reduction for playground equipment with the smooth plastic
surfaces. For metal playground equipment with rusted areas, cleaning with scrubbing
brushes was effective for dose reduction, although it was limited.

6）Forests and treesA) Deposition status of radioactive cesium(Evergreen forests)
The tendency was observed that the residual radioactive cesium was remaining higher inlitter layers containing the fallen leaf layer which was formed newly during 2011
It was observed that the amounts of residual radioactive cesium were small in the bark
portions of tree trunks in comparison with other parts. It is thought that most of theradioactive cesium deposited in the leave and the branches and could not reach the trunk
part.
Radioactive concentration of fallen leaf layer formed by dropping of leaves which grew at
the time of the accident (the surface layer that was formed by the newly fallen leaves during
the year of the accident) was high compared with deciduous trees. It is thought that inevergreen trees, much more radioactive cesium deposited on the leaves, which grew at thetime of the accident, compared with other parts.
(Deciduous forests)
It was found that much radioactive cesium was depositing and remaining in the litter layer
and outer bark of the trees. It is thought that this was because not many leaves had grownat the time of the accident.
The amount of residual radioactive cesium has been compared between the fallen leaf layer
which was formed during the year of the accident and the fallen leaf layer which had been
formed before the accident under the fallen leaf layer during the year of the accident. As aresult, the former (fresh layer) had a generally smaller quantity of radioactive cesiumcompared with the latter (older layer). This is also considered to be because not many leaves
had grown at the time of the accident, most of the radioactive cesium that fell on deciduoustrees was deposited on the ground surface under the trees, and then, the accident year’s
fallen leaf layer was formed on the contaminated ground surface.

B) Decontamination methods and results
Implementing both "weeding" and "removal of the accident year’s fallen leaf layer" mayhave (limited) effects of dose reduction in evergreen forests.
On the contrary, in deciduous forests, surface contamination density was increased by
implementing both "weeding" and "removal of the accident year’s fallen leaf layer". It isconsidered that, at the time of the accident, radioactive cesium deposited on the groundsurface; The ground surface was covered afterwards by new grasses which grew thickly andthe accident year’s fallen leaves without radioactive cesium contamination; and theradiation from the ground surface was shielded by them.
It was observed that surface dose rate and surface contamination density were reduced to a47

certain extent by "removing the litter layer" in addition to "weeding" and "removal of theaccident year’s fallen leaf layer" for both deciduous forests and evergreen forests. However,
it is necessary to consider that removal of the litter layer may have impacts on forest
ecosystems, such as changes in nutrient of soil.
High-pressure water washing for trunks of trees with some barks peeled off but with noadverse effects on their growth had high decontamination effects.

（4） Outline of results for works associated with decontamination
1）Disposal of wash water
Effluent criteria were able to be satisfied by using the combined processing methods offiltration, adsorption, and coagulation/sedimentation, according to the degree ofcontamination of wash water in each spot (including the stagnant water in side ditches) or
stagnant (pond) water before the accident.

2）Volume reduction methods of removed wastes such as branches and leaves
Crushing machines could reduce volume of branches and leaves while preventing scatteringof dust with deposited radioactive materials to the surroundings by applying dust collection
measures. However the volume of logs was not reduced so much, because logs were not sobulky even before crushing.
High temperature incineration could achieve extremely large volume reduction of branches
and leaves without spreading of the radioactive materials deposited on them together withthe exhaust smoke to the outside. Furthermore, it was confirmed that cesium concentrationin the exhaust gas was sufficiently lowered below the concentration limit of radioactive
materials in air specified by the law when treating the flue gas with bag filters or HEPA
filters.
Low temperature incineration was lower in volume reduction ratios than high temperatureincineration or crushing machines.

3）Generated amount of removed wastes
Generated amount of removed wastes greatly depends on differences in thedecontamination methods rather than the differences in annual cumulative dose of
decontamination implementation areas.
If the decontamination methods such as "topsoil stripping", "weeding", "removal of
fallen leaves, etc." are selected for decontamination works, larger amount ofremoved wastes is generated.
As shown in (3) 3), the effectiveness in dose reduction by "inversion tillage" or"interchanging topsoil with subsoil" is equivalent to that by "surface soil
stripping-off". However, "inversion tillage" or " interchanging topsoil with subsoil"
does not result in the generation of waste removed soil.
More than 80% of radioactive materials can be reduced in most places by removing surface
soil to approximately 5 cm, regardless of the level of annual cumulative dose and land-use
classification. However, the thickness of the stripping that directly relates to the amount ofgenerated soil to remove should be set in consideration of both the vertical distribution ofradioactivity concentrations and the decontamination targets.
The vertical distribution of radioactive material concentrations in the ground has atendency that the reduction rate of the concentration (the rate of concentration
decrease per each 1 cm in depth) significantly decreases as it goes deeper(exponentially decreasing)For example, when 80% of the radioactive materials are included in the top 5 cm of
the ground and 90% in the top 8 cm, the additional dose reduction of 10% is
expected by removing the additional layer of 3 cm below 5 cm deep in comparison
with removing the top 5 cm for removing 80% of radioactive materials. However,
the amount of removed objects would increase by 60%..
48

Surface soil may have to be stripped off more deeply to lower the density ofradioactive materials of the topsoil below the fixed absolute value in the areas withhigh annual cumulative dose.
However, the concentration distribution of radioactive materials in theunderground depth direction may be different from that of the demonstration
model projects for decontamination implemented to date, depending on
unevenness of the ground surface and other factors. Therefore, the concentration
distribution of radioactive materials in the ground depth direction should bechecked first before starting decontamination works, and then the stripping
thickness to achieve the decontamination target needs to be determined.

4）Temporary storage sites/on-site storage sites
When installing temporary storage sites and the like, the planned sites must be
decontaminated in advance and appropriate shielding measures have to be taken after thewastes are loaded and emplaced. Therefore, air dose rates in temporary storage sites do notincrease but rather decrease after loading and emplacement of wastes, regardless of thelevel of air dose rates of the sites before installation.
Air dose rates are also reduced by covering removed wastes with sandbags filledwith uncontaminated soil.
When bringing the removed objects into the storage sites and placing them therein, theradiation influence from those with high surface dose rates can be reduced by placing
them at the center of the site, and those with lower surface dose rates are placedaround them. By doing so, the influence of radiation from the removed objects withhigh surface dose rates can be reduced by the shielding effect of the removed objects
themselves.
Types of temporary storage sites have to be selected based on the opinions of municipalities
and residents, and taking into account topographical characteristics, land use situation,
and available area of the target sites.
Aboveground storage is the easiest type for shipment of stored wastes to theInterim Storage Facility. On the other hand, when installing the storage sites onsoft ground, it is necessary to improve the foundation.
Underground storage has the advantage that the soil for the shielding can be
secured at the sites. On the other hand, it takes time to excavate the underground
portion, and measures have to be taken, for instance, for stopping groundwater
inflow.
For semi-underground storage, it is possible to increase the storage capacity evenfor a limited place of the sites. However, it takes time to excavate the underground
portion. In addition, it is necessary to apply rainwater infiltration measures at theboundaries of the aboveground portion and the underground portion.

5）Radiation exposure dose control of decontamination workers
Exposure doses of decontamination workers were studied for each decontamination target
area. The workers in areas with higher air dose rates monitored before decontamination
generally had higher exposure doses. Nevertheless, exposure doses of workers in the areas
with annual cumulative dose less than 50 mSv and with appropriate measures for exposure
control were well below the reference value of the exposure dose limit stipulated by laws
and ordinances.
On the other hand, exposure doses of workers in the areas exceeding the annual cumulative
dose of 50 mSv may exceed the exposure dose limit stipulated by laws and ordinances, if
they work continuously for five years in those areas. Therefore, in such cases, more
stringent radiation control is required, such as optimizing the combination of
decontamination methods and work procedures for dose reduction, and promoting the work
efficiency by utilizing machines.

496）Costs for each decontamination method
Costs required for the works using the decontamination methods which bring larger dose
reduction effect tend to be higher.
It should be noted that, as can be seen in the following cases, it is necessary to consider
overall factors including costs, the volume of removed wastes to be generated, andworkability in addition to the dose reduction effect, when selecting decontamination
methods.
The case in which different decontamination methods with the same level effect ofdose reduction have different features regarding costs, the generated amount ofremoved wastes, and workability.
The case in which different decontamination methods with the same level effect ofdose reduction and cost requirements have different features of workability.

（5） Results of the implementation of area-wide decontamination works in demonstration
model projects for decontamination
Decontamination works were carried out in the areas where the radiation level before
decontamination had been higher than the level to cause the annual cumulative dose of 20
mSv or more and below 30 mSv. The works cold reduce the radiation level to cause theannual cumulative dose below 20 mSv.
Decontamination works were also carried out in the areas where the air dose rate before theworks was higher than the level to cause the annual cumulative dose exceeding 40 mSv.
After the works, the air dose rate could be reduced by around 40-60%. However, it was notpossible to reduce the level to a level to enable the annual cumulative dose below 20 mSv.
Decontamination work was carried out in Ottozawa area, Okuma Town, where the air dose
rate before the works had been at the level to cause 300 mSv or more as the annual
exposure dose. After the works, the air dose rate could be reduced more than 70% in
farmland and residential places. However, the air dose rate was not able to be reduced to alevel to achieve 50 mSv/year or less for the whole area.
In some areas with lower air dose rates before decontamination, decontamination methods
that do not generate much waste were tested. Although the amount of removed wastes was
relatively small, the reduction in air dose rates was lower compared with the case in higher
air dose rate areas.

（6） Guidance on decontamination works
The findings obtained in the demonstration model projects for decontamination are summarized in the formof guidance62 and have been published for the following eight items.
Guidance on obtaining informed consent (agreement acquisition) concerning thedecontamination implementation areas, selection of temporary storage sites and theirstakeholders
Guidance on monitoring
Guidance on decontamination works
Guidance on preparation and maintenance for temporary storage sites/on-site storage sites
Guidance on screening (contamination inspection)
Guidance on the treatment of wastes generated by decontamination works
Guidance on workers’ occupational safety management
Guidance on supervision for outsourcing companies

62Source: published on JAEA home page (http://fukushima.jaea.go.jp/initiatives/cat01/entry02.html )50

（7） Important findings obtained in demonstration model projects for decontamination
1）Important findings obtained for establishment of the work environment
In restricted areas, it is important to secure site offices and rest places which serve as bases
in decontamination works and securing water for decontamination. If rest places are notsecured in time, the limitation occurs in the length of working hours in which workers canwork continuously. If water cannot be secured on site, it must be brought from outside therestricted areas. As the facilities for rest places and the like, it was effective to utilize publicgrounds and public facilities, because coordination with the persons concerned for their use
could be made in a short period of time.
Machinery and equipment to be used for decontamination works might be possible toprocure on a, lease contract, but there were cases in which to bringing them into therestricted area was refused. When procuring them on a lease contract, it is necessary toprovide sufficient information to the lease companies on the appropriate contamination
inspection of the machinery and equipment, and the appropriate decontamination methods
to apply when needed and other conditions, and to clear the concerns of these companies.
Damage conditions of houses were investigated by outsourced specialty companies. The
contents of the investigation were based upon a construction damage investigation ofdamage possibilities by decontamination works. The investigation did not include
applicable environmental conditions and construction constraints for decontamination
works, for example, investigations to determine whether it was possible to set up
scaffolding on roofs for the works were not included. Therefore, it will be an efficientapproach in the damage survey of houses for the subsequent decontamination works, notonly investigating the damage conditions, but also checking whether the houses are in suchenvironmental conditions in which appropriate decontamination methods for the houses
concerned can be applied technically, and whether there are concerns about construction
constraints for decontamination works.
For large-scale decontamination works, there may be many places where wash water is
produced. Therefore, difficulty was foreseen to set up water treatment facilities in one place
for a long term. For this reason, a water treatment system, such as a vehicle-mounted one,should be considered, which can move to the places where the wash water is generated.

2）Important findings obtained for monitoring
Regarding the monitoring to locate hot spots, there were cases which caused the residents’complaint. Such cases occurred when the hot spots could not be located in the
pre-monitoring stage and they were found later by the residents’ own measurement after
the decontamination works. Important knowledge obtained regarding monitoring is:
It is necessary to set the number of monitoring points per house in a flexible way,
not to fix it at a certain number, in order to prevent overlooking of the necessary
decontamination works.
In mesh measurements, the measurement in shorter pitches gives better accuracy,
but the workload increases instead. For optimization, a combined use of back-packtype or buggy type instruments in mesh measurements was more effective than
expanding the measurement pitches of mesh measurements for preventing theoverlooking of hotspots.
For locating hotspots, it was effective to search for a place where the air dose rate
was relatively higher than other places in the surrounding by the measurement
device with shortened time constant for higher sensitivity. A two-dimensional dose
rate distribution evaluation system, which combined a GPS device and a dosimeter,
was an effective tool for locating hotspots because of its high spatial resolution, no
requirement of high measuring skills, and less data variation of measurements,and less risks of overlooking hotspots.
Risks of overlooking hotspots could be minimized by post-work monitoring by the work
leaders as a means of work result management, in order to locate any spots with high dose
rate or high surface contamination densitiesleft behind. So was for the soil and wastes to be
removed.
513）Important findings obtained for the influence of winter weather on decontamination
Generally in the snowfall, the measured radiation dose becomes lower due to the shielding
effect of the snow on the ground. In the demonstration model projects for decontamination,
the reduction effect of dose rate due to snow was evaluated quantitatively. As the resultrough evaluation of dose rate has become feasible even when snow-covered.
Machinery and equipment for decontamination may be subjected to freezing in midwinterand the working efficiency may be significantly affected. It has been recognized that anti
freezing measures should be considered, by keeping them in shelter, for instance.
Sometimes the soil solidifiers did not work for topsoil stripping during the winter because of
low temperatures. In some other cases, the frozen layer of topsoil was stripped off up to thefrozen depth at one time, thicker than the preset thickness to strip. The amount of removed
objects thus increased. On the other hand, however, it has been recognized that the surface
soil could be stripped off effectively by using road surface cutting machines.
Following risks have been also recognized: Frozen top soil when stripped off or frozen soil
for shielding may increase the amount of seepage water after they are transferred to thetemporary storage sites; flexible container bags for shielding (hereinafter referred to as"flexible containers") may deform and subside; or the welded portion of impervious sheets
may fail. Furthermore, risks of deformation of water collection boxes have been also
noticed.

4）Important findings obtained for maintaining the quality of decontamination works
A tendency was noticed in decontamination works that the decontamination effects varied
depending on the work methods of individual workers. Particularly, in top soil stripping,soil was occasionally spilled during plowing regardless of hand work or machine work. Thishas been noticed as one of the causes for differences in the decontamination effects.
When decontaminating by top soil stripping with the stripping thickness under control,
grass roots in the actual soil surface impeded stripping off in the predetermined thickness,
Sometimes it became necessary to remove grass roots and then to strip the topsoil off
beyond the predetermined thicknesses. In the land with irregularities, it was also necessary
to strip off thicker layers than the predetermined values. In order to reduce the deviationfrom the predetermined stripping thickness, prior rolling compaction has been effective.
It has been found that both coagulating sedimentation method and filtration method had
advantages and disadvantages for the treatment of recovered wash water. For example, forthe coagulating sedimentation method, the device is simple and it is easy to use, but theprocess such as water removal from the sediment and solidification of the sediment isrequired. On the other hand, in the filtration method, residues are solid and it is easy tohandle them. However, it takes time to complete the filtration, and measures such as thereverse washing because of blocking of the filter are required. In addition, while thecoagulating sedimentation method is a batch process, the filtration method can be runcontinuously. It is difficult to recommend unconditionally which processing method can beused for recovered wash water. This is because the process to be used varies according to
the properties of treated water and the required amount of processing. As a result, the useof the processing method according to the situation or the use of a combination of processing
methods is effective for treating recovered wash water.

5）Important findings obtained for the prevention of re-contamination
The places that had been decontaminated were distinguished using colored cones and othermeans, and furthermore measures were taken to prohibit entering those places at the timethe decontamination works were being done. These actions were effective for the preventionof re-contamination.
It should be noted that, in the demonstration model projects for decontamination, daily
monitoring has been carrying out continuously at the fixed points, including the points
where individual decontamination works had been completed. As a result, during the period52

of around one month from the end of the decontamination works to the end of the projects,
hardly any situations such as a dose rate increase after the completion of decontamination
works have been observed. In other words, the influence of significant secondary
contamination have not been seen.

6）Important findings obtained for the volume reduction of wastes
Among flammable decontamination wastes, branches and leaves generated from forests
and the undergrowth of weeds such as the bamboo grass were bulky when stored in flexible
containers. Therefore, the filling efficiency of the flexible containers could not be increased.
Incineration was a very effective treatment method because the volume reduction rate washigh and spread of radioactive cesium was suppressed by installing filters for the exhaustgas. However, it is necessary to note that the equipment is relatively large-scale and theincineration ash must be handled.
Wood crushers and wood chippers were effective processing devices. This was because theirvolume reduction rate was relatively high although it depended on the processing targets,and the equipment was not large in scale. However, when wood chippers were used, it was
desirable to take measures such as laying dust sheets around the equipment because thescattering of small pieces of wood is expected.
For volume reduction of undergrowth generated from vast grasslands, compression by anundergrowth accumulation machine attached to a tractor (roll baler) was regarded as anefficient method from the viewpoint of volume reduction rate and work efficiency, although
the human power to accumulate undergrowth of weeds was required.
Volume reduction by compressing dead leaves with a heavy loader vehicle and volume
reduction by sucking off air in sealed bags with large vacuum cleaners that can be easily
carried into fields were other measures.
Soil stripped from farmland (especially pastures) and playgrounds, schoolyards, parks(especially lawn areas) included large numbers of plant roots. It is very effective from theviewpoint of control of the waste amounts that the stripped soil portions are separated into
soil and flammables (plant roots). In order to separate in this way, twisters63 and vibration
sieve machines were used. This technique cannot be evaluated with a numerical value ofseparation rate because separation depends on what are included as the non-flammables(such as soil and stones) and what are included as the flammables (such as plant roots). The
results of the separation tests of soil and plant roots were confirmed by visual inspection.
For test conditions that were good, flammables such as many roots were not included in theseparated soil. Therefore, it was possible to control the separated soil as non-flammables.
Consequently, this method was considered to be effective from the viewpoint of waste
management. When highly viscous soil was treated (clay), the soil could not be broken by
the twister and therefore a large amount of soil was separated to the root side (flammables).
Thus, it was also found that it is necessary to pay attention to the soil properties.
Combination treatment method was considered, in which grass roots that have been
separated by the twister were processed by low temperature incineration using a rotary
dryer 64 . In this case, all the wastes that were left after burning could be treated as
non-flammables.

7）Important findings obtained regarding the anxiety of residents
From local residents, including the landowners, and local governments, there were many
requests to report the progress of decontamination works and the effect of dose reduction bydecontamination. It has been found to be important to respond to these requests politely. To
promote decontamination works while building the relationship of mutual trust with local
governments and local residents, it was important that information control be implemented
63 Twister (rotary crushing mixer) (Machinery for crushing and mixing the soil with striking force of a chain

rotating at high speed)

64 Rotary (tumble) dryer (Machine for heating and drying the soil containing moisture in a rotating tube)

53

without exception to prevent release of personal information, while ensuring that the
information on the details and the results of the works were offered regularly as far as
possible.
Many concerns were voiced from residents regarding downstream contamination by washwater. Downstream contamination by wash water was found to be one of the biggest causesof uneasiness. Therefore, when decontamination works were carried out using water, it was
important to take outflow prevention measures such as providing weirs in roadside ditches
where wash water flowed into. In the case of high-pressure water washing of houses andgarden planting, it was possible to prevent secondary contamination by removing concrete
facings and surface soil under the planting and near the house after high pressure water
washing.

8）Important findings obtained for safety protection of the decontamination workers
At the places where the levels of contamination were estimated to be especially low, it wasconsidered at first that the wearing of sealed chemical protective clothing and a full-facemask was not always necessary, if post-work contamination checks of workers were
thoroughly carried out. However, in the case of actual works, some workers could not feelrelieved without wearing these protective items, and heavily equipped workers, who wore
both the sealed chemical protective clothing and the full-face mask, were found here andthere. Not only was it necessary to explain safety to workers scientifically, but also it wasalso important to remove workers’ anxiety.
For the workers, not only radiation protection but also measures to protect from pests(particularly bees and vipers) were necessary. In addition, it was found that measures toprotect workers from the danger caused by livestock and pets which had gotten free fromowners were necessary.
It was not only residents that felt uneasy as to whether decontamination was carried out
appropriately. It was found that there was a case in which workers were performing
decontamination works while feeling uneasy whether the works were being carried out
appropriately. Particularly, in the topsoil stripping by human power, it was difficult tocheck whether there was any omission of stripping or any unremoved soil by only visualinspection. Therefore, personnel qualified to make dose measurements were present in thefields during decontamination works, and the effect of dose reduction was confirmed in atimely manner. This was effective in the prevention of redoing of decontamination works
and in the prevention of excessive decontamination.

1.1.7. Outline of the Intensive Contamination Survey Areas（1） Designation of Intensive Contamination Survey Areas
Intensive Contamination Survey Areas are designated by the MOE as the areas where it is necessary toinvestigate and measure the status of the environmental contamination due to the radioactive materials
discharged in the areas by the accident mainly.
In Intensive Contamination Survey Areas, designated municipal mayors have developed theirdecontamination plans unlike those of the Special Decontamination Areas as described in 1.1.4, andmunicipalities have been implementing decontamination works steadily.

（2） Designation status of Intensive Contamination Survey Areas
The designation status of Intensive Contamination Survey Areas is not fixed because there are also someareas where the designation was lifted after the determination65. The municipalities listed in Table 1-7 are
the designated the Intensive Contamination Survey Area as of February 1, 2015. Municipalities designated65 For some municipalities, the designation of Intensive Contamination Survey Area was lifted because thedecrease in air dose rates led to the fact of the qualification for designation.

54

as the Intensive Contamination Survey Area and Special Decontamination Area are shown in Figure 1-22
through Figure 1-29, together with the progress of decontamination works in those municipalities.

55

Table 1-7 Designation status of Intensive Contamination Survey Areas (as of February 1,2015)66
Prefectures Municipalities
Fukushima
Prefecture

Fukushima City, Koriyama City, Iwaki City, Shirakawa City, Sukagawa City,
Soma City, Nihonmatsu City, Date City, Motomiya City, Koori Town, Kunimi
Town, Otama Village, Kagamiishi Town , Tenei Village, Aizubange Town,
Yugawa Village, Yanaizu Town, Aizu Misato Town, Nishigo Village , Izumizaki
Village, Nakajima Village, Yabuki Town, Tanagura Town, Yamatsuri Town,
Hanawa Town, Samegawa Village, Ishikawa Town, Tamagawa Village, Hirata
Village, Asakawa Town, Furudono Town, Miharu Town, Ono Town, Hirono
Town, Shinchi Town, Tamura City, Minami Soma City, Kawamata Town And
Kawauchi Village

Iwate
Prefecture

Ichinoseki City, Oshu City, Hiraizumi Town

MiyagiPrefecture
IbarakiPrefecture

Shiroishi City, Kakuda City, Kurihara City, Shichikashuku Town, Ogawara
Town, Marumori Town, Watari Town, Yamamoto Town
Hitachi City, Tsuchiura City, Ryugasaki City, Joso City, Hitachiota City,
Takahagi City, Kitaibaraki City, Toride City, Ushiku City, Tsukuba City,
Hitachinaka City, Kashima City, Moriya City, Inashiki City, Hokota City,
Tsukubamirai City, Tokai Village, Miho Village, Ami Town, Tone Town
Sano City, Kanuma City, Nikko City, Otawara City, Yaita City, Nasushiobara
City, Shioya Town, Nasu Town
Kiryu City, Numata City, Shibukawa City, Annaka City, Midori City,
Shimonita Town, Nakanojo Town, Takayama Village, Higashiagatsuma Town,
Kawaba Village
Misato City, Yoshikawa City

Tochigi
Prefecture
Gunma
Prefecture
SaitamaPrefecture
Chiba
Prefecture

Matsudo City, Noda City, Sakura City, Kashiwa City, Nagareyama City, AbikoCity, Kamagaya City, Inzai City, Shiroi City

66Source: Ministry of the Environment (MOE), "Decontamination information site"(the same source for Figure 1-22 to Figure 1-29)

56

Areas where decontamination is implemente d by thenational government (special decontamination areas)
Completion/Evacuation order lifting

Not ordering

Completion of decontamination works

Special decontamination areas

Started already

Difficult-to-return areas

O utsourced alreadyAreas where decontamination is implemented by eachmunicipality(intensive contamination survey areas)
Municipalities where the designation of intensive contamination survey
areas was lifted.
Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)
Other intensive contamination survey areas

Figure 1-22 Designation status of Intensive Contamination Survey Area/ Special
Decontamination Area and progress of decontamination works in Fukushima Prefecture.

Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)

Figure 1-23 Designation status of Intensive Contamination Survey Area and progress of
decontamination works in Iwate Prefecture.

57

Municipalities where the designation of intensive contamination survey
areas was lifted.
Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)

Figure 1-24 Designation status of Intensive Contamination Survey Area and progress of
decontamination works in Miyagi Prefecture.

Municipalities where the designation of intensive contamination survey
areas was lifted.
Compression of implementation of decontamination and othermeasures based on decontamination implementation plan
Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)
Other intensive contamination survey areas

Figure 1-25 Designation status of Intensive Contamination Survey Area and progress of
decontamination works in Ibaraki Prefecture.

58

Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)

Figure 1-26 Designation status of Intensive Contamination Survey Area and progress of
decontamination works in Tochigi Prefecture.

Municipalities where the designation of intensive contamination survey
areas was lifted.
Compression of implementation of decontamination and othermeasures based on decontamination implementation plan
Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)
Other intensive contamination survey areas

Figure 1-27 Designation status of Intensive Contamination Survey Area and progress of
decontamination works in Gunma Prefecture.

59

Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)

Figure 1-28 Designation status of Intensive Contamination Survey Area and progress of
decontamination works in Saitama Prefecture.

Planed already(Areas where decontamination plans were developed by eachmunicipality based on the Act on Special Measures Concerning theHandling of Radioactive Pollution)

Figure 1-29 Designation status of Intensive Contamination Survey Area and progress of
decontamination works in Chiba Prefecture.

60

（3） Implementation system of decontamination works in Intensive Contamination Survey
AreasIn Intensive Contamination Survey Areas, surveys and measurements of thecontamination status are carried out first by the mayors and other officials of the municipalities
with financial support by the National Government.
Based on the results of surveys and measurements, decontamination plans are developedby the mayors and others. In formulating the decontamination plan in each municipality, theconsultation with the Minister of the Environment is done in advance. Through thisconsultation, determinations and recommendations are made about the adequacy of plancontents, and then planning is checked whether it corresponds to the works targeted for thebudget support.
After the check has been completed, securing of temporary storage sites, reaching theconsensus with stakeholders about the decontamination works, ordering of thedecontamination works, implementing the decontamination works, and post-work
investigation and verification are carried out sequentially by each municipality, in accordancewith their own decontamination plan. All the costs for these works by each municipality arecovered with the National Government financial support.
In addition, for the implementation of decontamination works in the target areas describedin each municipality’s plan, it is prescribed in the Act on Special Measures that the National
Government has the responsibility for the land under national control, and each prefecture
has the responsibility for the land under its own control.

（4） Progress in Intensive Contamination Survey Areas
Progress of implementation of the decontamination works and other measures in Intensive
Contamination Survey Areas are described below for Fukushima Prefecture and other prefectures.

1）Fukushima Prefecture
Status of the ordering of decontamination works and the development of decontaminationplans in Fukushima Prefecture is shown in Figure 1-30. Most ordering has been completed.
However, for roads and forests (in the living space), the progress of their ordering is delayed.

61

House (number of houses)

Public facilities, etc. (number of facilities)

Number ofcompleted

204,957

Number ofcompleted

6,694

Number ofoutsourced

299,641

Number ofoutsourced

7,873

Plannednumber315,498

Plannednumber(reference) Total number planned = 431,042 houses

Road (km)Number ofcompleted
Number ofoutsourced
Plannednumber8,266(reference) Total number planned = 8,683 facilities

Farmland (paddy + field + orchard + pasture; ha)

3,550

Number ofcompleted

21,744

6,171

Number ofoutsourced

28,955

8,529

Plannednumber30,012(reference) Total number planned = 15,512km(reference) Total number planned = 34,108ha

Forest (within the range of living area) (ha)Number ofcompleted

1,098

Number ofoutsourced

1,470

Plannednumber

1,961※Planned number is the number of decontamination
works expected to be completed by the end of the
fiscal year 2014.

(reference) Total number planned = 3,314ha

Figure 1-30 Progress of decontamination works in Intensive Contamination Survey Areas in
Fukushima Prefecture (as of end of January 2015)67 .

2）Outside Fukushima Prefecture
Implementation status of decontamination and other measures in Iwate, Miyagi, Ibaraki, Tochigi, Gunma,
Saitama and Chiba Prefectures is shown in Table 1-8 through Table 1-15.
The decontamination has already been completed or almost been completed in more than 70% of themunicipalities.
Table 1-8 Completion status of implementation of decontamination and other measures basedon decontamination implementation plans outside Fukushima Prefecture68(as of end of December, 2014) (Number of municipalities)(a)Completed(b)Almost completed(c)Continued(d)Total

Iwate Prefecture

0

2

1

3

Miyagi Prefecture

0

3

5

8

Ibaraki Prefecture

11

7

1

19

Tochigi Prefecture

0

4

4

8

Gunma Prefecture

7

1

1

9

Saitama Prefecture

0

2

0

2

Chiba Prefecture

0

8

1

9

Total number

17

26

15

58

67Source: Fukushima Prefecture, "Decontamination implementation status in decontamination areas(Intensive Contamination Survey Areas) in municipalities (February 27, 2015 update) "（https://www.pref.fukushima.lg.jp/site/portal/progress201501.html
68Source: Ministry of the Environment (MOE), "Compiled of progress survey results (as of end of December,2014)" (February 13, 2015) (the same source for Table 1-9 to Table 1-15)

62

Table 1-9 Progress of implementation of decontamination and other measures based on
decontamination implementation plan outside Fukushima Prefecture (Schools and nurseryschools, etc.)(as of end of December, 2014)(Number of facilities)(a)Planned
number(b)Outsourced
number(c)Completed
numberNumber of unnecessary
decontamination works in (a),(b) and(c) [the number that decontamination
works were determined to beunnecessary by prior monitoring
results]

Iwate Prefecture

242

242

242

(54)

Miyagi Prefecture

95

95

94

(10)

Ibaraki Prefecture

329

329

329

(42)

Tochigi Prefecture

232

232

231

(5)

Gunma Prefecture

24

24

24

(7)

Saitama Prefecture

48

48

48

0

Chiba Prefecture

593

593

593

(99)

Total number

1,563

1,563

1,562

(217)

Table 1-10 Progress of implementation of decontamination and other measures based on
decontamination implementation plan outside Fukushima Prefecture (Parks and sports
facilities)(as of end of December, 2014)(a)Planned
number(Number of facilities)(b)Outsourced
number(c)Completed
numberNumber of unnecessary
decontamination works in (a),(b)and (c) [the number that
decontamination works were
determined to be unnecessary
by prior monitoring results]

Iwate Prefecture

335

335

335

(268)

Miyagi Prefecture

153

150

149

(56)

Ibaraki Prefecture

888

887

887

(335)

Tochigi Prefecture

741

736

436

(241)

Gunma Prefecture

41

41

41

(18)

Saitama Prefecture

94

94

94

0

Chiba Prefecture

1,672

1,672

1,672

(143)

Total number

3,924

3,915

3,614

(1,061)63

Table 1-11 Progress of implementation of decontamination and other measures based on
decontamination implementation plan outside Fukushima Prefecture (Housing）(as of end of December, 2014)(a)Planned
number(b)Outsourced
number(Number of houses/buildings)
Number of unnecessary
decontamination works in (a),(b)and (c) [the number that
decontamination works were
determined to be unnecessary
by prior monitoring results](c)Completed
number

Iwate Prefecture

18,621

15,321

15,321(15,207)

Miyagi Prefecture

10,228

8,503

7,350

(2,972)

Ibaraki Prefecture

47,27647,27647,266(45,143)

Tochigi Prefecture

38,05437,71834,065(13,712)

Gunma Prefecture

6,192

6,192

6,165

(4,760)Saitama Prefecture

0

0

0

0

Chiba Prefecture

19,15919,15919,159(10,919)

Total number

139,530

134,169

129,326(92,713)

Table 1-12 Progress of implementation of decontamination and other measures based on
decontamination implementation plan outside Fukushima Prefecture (Other facilities)(as of end of December, 2014)(a)Planned
number(Number of facilities)(b)Outsourced
number(c)Completed
numberNumber of unnecessary
decontamination works in (a),(b)and (c) [the number that
decontamination works were
determined to be unnecessary
by prior monitoring results]

Iwate Prefecture

3,098

2,577

2,577

(2,445)

Miyagi Prefecture

348

348

332

(180)

Ibaraki Prefecture

634

634

634

(543)

Tochigi Prefecture

402

353

223

(136)

Gunma Prefecture

123

122

122

(86)

Saitama Prefecture

8

8

8

0

Chiba Prefecture

227

227

227

(130)

Total number

4,840

4,270

4,124

(3,520)64

Table 1-13 Progress of implementation of decontamination and other measures based on
decontamination implementation plan outside Fukushima Prefecture (Roads)(as of end of December, 2014)(a)Planned
number(m)(b)Outsourced
number(c)Completed
numberNumber of unnecessary
decontamination works in (a),(b)and (c) [the number that
decontamination works were
determined to be unnecessary byprior monitoring results]

Iwate Prefecture

2,151,600

2,140,600

2,140,600(2,140,400)

Miyagi Prefecture

332,40973,232

73,232(32,726)

Ibaraki Prefecture

1,164,205

1,120,705

1,120,705(1,117,240)

Tochigi Prefecture

81,40281,40281,402(76,875)

Gunma Prefecture

203,378

203,378

203,378(201,502)

Saitama Prefecture

3,409

3,409

3,409

0

Chiba Prefecture

232,874

232,874

232,874(137,388)

Total number

4,169,277

3,855,600

3,855,600(3,706,131)

Table 1-14 Progress of implementation of decontamination and other measures based on
decontamination implementation plan outside Fukushima Prefecture (Farmland andpastures)(as of end of December, 2014)(a)Planned
number(m2)(b)Outsourced
number(c)Completed
numberNumber of unnecessary
decontamination works in (a),(b)and (c) [the number that
decontamination works were
determined to be unnecessary
by prior monitoring results]

Iwate Prefecture

0

0

0

0

Miyagi Prefecture

557,000

557,000

217,000

0

Ibaraki Prefecture

0

0

0

0

Tochigi Prefecture

12,278,300

12,278,300

12,142,000(3,755,900)

Gunma Prefecture

1,043,597

1,043,597

1,043,597(951,708)

Saitama Prefecture

0

0

0

0

Chiba Prefecture

0

0

0

0

13,878,997

13,878,897

13,402,597(4,707,608)

Total number

65

Table 1-15 Progress of implementation of decontamination and other measures based on
decontamination implementation plan outside Fukushima Prefecture (Forests (Nearby living
areas))(as of end of December, 2014)(a)Planned
number(m2)(b)Outsourced
number(c)Completed
numberNumber of unnecessary
decontamination works in (a),(b)and (c) [the number that
decontamination works were
determined to be unnecessary
by prior monitoring results]

Iwate Prefecture

0

0

0

0

Miyagi Prefecture

2,000,000

2,000,000

1,029,709(185,355)

Ibaraki Prefecture

7,186

7,186

7,186

0

Tochigi Prefecture

831,760

831,760

831,760

0Gunma Prefecture

60,15554,55553,755(38,563)

Saitama Prefecture

0

0

0

0

Chiba Prefecture

0

0

0

0

2,899,101

2,893,501

1,922,410(223,918)

Total number

1.2. Features of contamination
1.2.1. Dispersion status of radioactive materials
Radioactive materials were discharged from the damaged nuclear reactors at the 1FNPS. The total
amount of radioactive materials discharged in the period between March 11 and April 5, 2011, wasestimated to be approximately 1.5 x 1017 Bq for iodine-131 and approximately 1.3 x 1016 Bq for
cesium-137 (estimated based on the data of environmental monitoring, etc. using an atmospheric dispersion
factor)69. A massive amount of radioactive materials was dispersed into the atmosphere.
The results of various monitoring surveys confirmed that radioactive materials had dispersed into wide
areas, not only into the evacuated areas but also into areas outside those defined as evacuation areas, as aresult of the accident, as mentioned in 1.1.2. For reference, Figure 1-31 shows the result of a monitoring
survey which was done using an aircraft by the MEXT during the period between October 22 andNovember 5, 2011. As understood when compared with the evacuation area shown in Figure 1-13,
contamination was confirmed not only in the areas to which an evacuation order was made (and residents
were no longer present), but also in the areas with residents present. The dose reduction activities wereneeded in such areas.
Because radioactive materials move over time as they are carried by rainfall and other factors and theease of accumulation varies by place, depending on the shape and material of structural objects, the dose
distribution had become uneven over time compared to the condition immediately after the accident, andthere occurred some localized high-dose points called hot spots (Figure 1-33). Such unevenly contaminatedconditions in micro and macro terms led to a difference in decontamination methods by areas and buildings
and accordingly caused concerns of the residents about the existence of high radiation sources in nearby
areas, as well as affecting their sense of fairness for the level of decontamination by area and house.
Detailed explanations and appropriate responses were required to address these issues.

69 Source: JAEA, "Summary of Estimation of Release Amounts of 131I and 137Cs Accidentally Discharged from

Fukushima Daiichi Nuclear Power Plant into the Atmosphere” (May 12, 2011)66

Legend

Air dose rates at the height of 1 m
above the ground surface(μSv/h)[Converted to the values as of 5
November]Areas where air dose
rate is not measured* Air dose rate due to natural radionuclides is included in this map.

Figure 1-31 Result of the Fourth Airborne Monitoring Survey (October to November 2011) by
MEXT (Air dose rates at the height of 1 m above the ground surface within an 80 km zone
from the 1FNPS)70 .

70Source: Ministry of Education, Culture, Sports, Science and Technology (MEXT), “Result of the Fourth

Airborne Monitoring Survey by MEXT” (December 16, 2011) (the same source for Figure 1-32)

67

Legend

Total accumulation of Cs-134 and137 on the ground surface (Bq/m2)[Converted to the values as of 5
November]Areas where air dose
rate is not measured

Figure 1-32 Result of the Fourth Airborne Monitoring Survey (October to November 2011)by MEXT (Total accumulation of 134Cs and 137Cs on the ground surface within an 80 km zone
from the 1FNPS).

68

Aizubange Town

Place where rainwater flows and drops

Bottom of downspout

Onami district, Fukushima-City

Exit of downspout

Place where rainwater flows

Figure 1-33 Monitoring of contamination status with gamma camera images at the hotspot
locations71 .

1.2.2. Major nuclides
Released radioactive materials included xenon-133, tellurium-132, strontium and plutonium in addition
to cesium and iodine.
Among them, strontium and plutonium were monitored from June 6 through June 14 and from June 27
through July 8, 2011 by the MEXT). As a result, plutonium-238 and plutonium-(239+240) were detected in
the northwest direction within the radius of 45 km from TEPCO’s 1FNPS, as shown in Figure 1-34.
However, the amount was within the monitoring level of the deposition quantity of plutonium due toatmospheric nuclear tests which had been monitored nationwide for 11 years before the accident, except for
one place (1.4 times of the maximum amount of plutonium monitored before the accident). Relatively highamount of strontium-89 and -90 has also been monitored on the ground surface in the northwest direction
from the 1FNPS. However, those quantities indicated a tendency to decrease as the distance got away fromthe power station. Based on these measurements, cumulative effective doses of 50 years were calculated forevery radionuclide which was deposited on the soil. As a result of these analyses, it was confirmed that the

71Source: "Discussion meeting with well-informed persons about decontamination ~Considering futurefrom the former knowledge in National Government and 4 cities ~ Fact book" (June 20, 2014
edition)(http://josen.env.go.jp/material/pdf/session_140615/session_140615_03_140620.pdf)

69

influences of radiation exposure due to the nuclides other than radioactive cesium are very small comparedwith those of radioactive cesium that was released in large quantities72.
Furthermore, as the half-lives of iodine 131, Xenon 133 and tellurium 132 are short with approximately
eight days, five days and three days, respectively, the influence of radioactive exposure due to these
nuclides becomes small after the early days of the accident. Therefore when considering person's radiation
exposure at present, important nuclides have become two of cesium 134 (half-life; about 2.1 years) andcesium 137 (half-life; about 30.2 years).

72According to the "Results of nuclide analyses of plutonium and strontium by the Ministry of Education,

Culture, Sports, Science and Technology (MEXT)", those are as follows. Cumulative effective doses of 50 years
have been analyzed in each place where the highest values were detected in the deposition amounts ofplutonium-238, plutonium-(239+240), and strontium-89 and -90. For them, plutonium-238 was 0.027 mSv,
plutonium-(239+240) was 0.12 mSv. Strontium-89 was 0.61μSv (0.00061 mSv), and strontium-90 was 0.12
mSv.
On the other hand, those values of cesium-134 and -137 were 71mSv and 2.0Sv (2,000mSv), respectively, ineach place where the highest values were detected for the deposition amounts of cesium-134 and -137.
In addition, in these analyses, the effect of dose reduction by decontamination is not included, and it isassumed to have stayed the same at the same place for 50 years.

70Legend
Deliberate
evacuation
area

Emergency
evacuation
preparationarea

Accumulation of Pu-238
and Pu-239+240 on the
ground surface(Bq/m2)(As of June 14)
Detection of Pu-238 andPu-239+240
Detection of Pu-238 only
Detection of Pu-239+240 only
Upper: Measured value of Pu-238
Lower: Measured value of Pu-239+240(2Km mesh)
10Km mesh(2Km mesh)

Places where plutonium 238 and 239+240 are considered to have been deposited newly due to the accident of Fukushima
Daiichi nuclear power plant

Figure 1-34 Measurement results of 238Pu and 239+240Pu on the ground surface73 .

73Source: Ministry of Education, Culture, Sports, Science and Technology (MEXT),"Results of nuclide analyses of plutonium and strontium by the Ministry of Education, Culture, Sports,
Science and Technology (MEXT)" (September 30, 2011) (the same source for Figure 1-36)

71

Legend
Deliberate
evacuation
area

Emergency
evacuation
preparationarea

Accumulation of Sr-89 andSr-90 on the ground surface(Bq/m2) (As of June 14)

Detection of Sr-89 and Sr-90
Detection of Sr-90 only
Upper: Measured value of Sr-89
Lower: Measured value of Sr-90(2Km mesh)
10Km mesh(2Km mesh)

Places where strontium 89 and Sr-90 are considered to have been deposited newly due to the accident of Fukushima Daiichi
nuclear power plant

Figure 1-35 Measurement results of 89Sr and 90Sr on the ground surface.

72

1.3. Features of decontamination
1.3.1. Unprecedented large-scale decontamination activities
Since radioactive materials have been dispersed across a wide area, decontamination works in Japan
associated with the accident at the 1FNPS have to be done in vast areas as indicated in 1.1.2 and 1.1.3: it isan extremely large-scale project that has not been seen before. We are also required to promote large-scaledecontamination projects that no one has ever done before, while obtaining the consents of related persons,such as owners of residential land. Moreover, we faced a large number of problems, as we did not haveenough time for planning. To solve these problems, various measures were taken and considerable efforts
were made.

（1） Establishment of strategic decontamination process
1）Implementation of large-scale decontamination with strategic decontamination process
The areas subjected to decontamination are extremely broad. There are several tens of
thousands to hundreds of thousands of residential land lots from which it is necessary toobtain consent, which means the number of involved persons such as owners is enormousand a great amount of time and manpower is required to obtain their consent. Therefore,
it is not necessarily efficient to hastily start a large amount of decontamination works at
one time before putting in place the system for decontamination.
To address such a situation, we implemented the “Demonstration model project fordecontamination” especially in the Special Decontamination Areas where the residents
had been evacuated and no restored infrastructures had been put in place. Throughdecontaminating local government offices and public facilities first, while confirming andaccumulating achievements and technical knowledge, we formed bases fordecontamination and restoration/reconstruction works, which led to smooth large-scaledecontamination (full-scale decontamination) works later.
In the full-scale decontamination, the strategic efforts by building bases were seen as
with the case of preliminary decontamination: these efforts were intended to increase thespeed of decontamination works as much as possible and improve the workplace safety of
the workers by first decontaminating the workers’ base for taking a rest.

2）Decontamination plan based on the weather
The weather varies greatly from season to season in Japan.
The demonstration model project for decontamination has proved that especially in winter it isdifficult to get accurate values of air dose rate due to the shielding effect of falling and accumulated
snow and there is a reduction in decontamination efficiency, increase in weight and volume of waste
due to the attachment of snow and problems in using cars, etc., as indicated in 1.1.6 (7). Therefore, it
has become a general rule not to perform decontamination forcedly during the time of snowfall andaccumulation in the full-scale decontamination.
Also, in the rainy and typhoon seasons, there are many concerns, including those for measuring
error, outflow of materials removed by decontamination, problems in recovering decontamination
waste water and concerns about worsening of the labor environment for decontamination workers.
Therefore, we make it a rule to stop the decontamination works under certain conditions of wind andrain.
Because we sometimes need to postpone the schedule of decontamination due to weather conditions,
we need to plan work schedules taking into account these impacts.
Although high temperature and solar insulation in summer do not affect the decontamination work
itself, they may result in a harsh working environment and have impacts on the health ofdecontamination workers. To address such a situation, we decided to work on decontamination withdue considerations for prevention of heat stroke and response to sudden illness depending on theweather, including wearing of protective clothing with cold packs and avoidance of working during73hours when temperatures are the highest, as well as raising the awareness of workers about heatstroke.

（2） Securing decontamination workers1）Securing the quantity of decontamination workers
While the decontamination work does not necessarily require a high level of skill, it has to be donewith consideration for the level of radiation dose and conditions of the decontamination objectives.
Also, only a very limited part can be done by machine. As a result, we need a large number ofworkers: the numbers of local workers that can be employed are not sufficient to secure the required
number of decontamination workers, and we needed to recruit widely from outside Fukushima
Prefecture.
However, the Great East Japan Earthquake which sled to the accident at the nuclear power station,
inflicted massive damage on the Tohoku region, mainly to Miyagi, Iwate and Fukushima Prefectures
as mentioned in 1.1.2 There have been large-scale restoration/reconstruction projects after theearthquake underway in Miyagi and Iwate Prefectures, and there has been a great demand forconstruction workers doing decontamination and other works also in the prefectures other than
Fukushima. Therefore, it has been very difficult to secure the required number of decontamination
workers.
Furthermore, many workers were required for works to be done on the site of the 1FNPS, which
added to the difficulty to secure the necessary number of decontamination workers.
Therefore, the MOE and local governments have worked to reduce concerns for becoming adecontamination worker, by introducing the details of decontamination work in an easy-to-understandway. In addition, they tried to secure decontamination workers by implementing various measures,
including payment of a special allowance in the Special Decontamination Areas.

2）Securing the quality of decontamination workers
Although decontamination work does not necessarily require a high level of skill, sufficient effects
may not be obtained if workers do not know the principle of decontamination and do not follow acertain procedure. Moreover, since radiation is not visible unlike ordinary contamination and dust, it
has the feature that we cannot tell whether a sufficient decontamination effect is obtained or notwithout measurement. If appropriate decontamination work is not done, it could lead to not only an
increase of removed substances, but also problems with residents. Therefore, securing the quality, as
well as the quantity, was required in recruiting decontamination workers.
On the other hand, it was difficult to secure a large number of workers who had knowledge andexperience in decontamination and radiation from the outset, because general citizens were notfamiliar with the knowledge of radiation, let alone decontamination, in Japan before the Great East
Japan Earthquake as mentioned in 1.1.1 Therefore, we had no choice but to nurture the knowledge of
decontamination through education. The efforts were made to provide many workers with education
about decontamination. For example, decontamination business operators provided the special
education and the newcomer education based on the Ionizing Radiation Ordinance fordecontamination to workers before starting decontamination work, as well as regular education andtraining on safety. They also implemented accident prevention activities and mutual checking ofradiation protection measures among workers on the site of work every morning before starting
decontamination work. In addition to the above, they themselves extracted and presented example
cases of successes and failures at work sites. The MHLW transmitted animated materials for special
education about decontamination on YouTube and Fukushima Prefecture and MOE held training
sessions on decontamination work for decontamination workers and site supervisors. These efforts
helped decontamination business operators perform educational activities more smoothly and easily.
Furthermore, decontamination workers are required to be of sufficient quality in terms ofconsideration to related persons and local residents as shown in 1.3.3, as well as in terms ofknowledge about decontamination. Especially, those from outside the decontamination area wererequired to exhibit behavior and awareness worthy of getting the trust of related persons and residents.
Moreover, the work of decontamination is unlikely to give a sense of accomplishment to workers,
74unlike civil engineering work and construction which are actions of making structural objects. A highlevel of patience is also required for decontamination workers to continue the work without degradingits quality, because they have to continue relatively monotonous work of decontamination endlessly
while placing extra effort on radiation protection. Therefore, how to maintain the motivation of theworkers was a critical issue.
The workers from the disaster-affected areas could maintain their motivation when they saw the
improved appearance as a result of their work such as mowing and they could feel their hometowns
were being restored. However, it is not always true for the workers from outside the areas. To maintainand secure their motivation, various efforts were made, including making repetitive communications
about what their efforts would bring about, showing the effects of their work by comparing the data
before and after decontamination, and conveying voices of appreciation and encouragement from thelocal people.

（3） Preparation of project environment
To perform this great amount of unprecedented decontamination work, it is also important to
prepare uniform procedures and systems to order and perform the work smoothly as a project, as wellas the strategic process as shown in (1) above and the securing of the quantity and quality of workers
as shown in (2) above.
Since there were a limited number of personnel at the MOE who had the experience of
implementing public works as a direct control project, they used the existing rules and systems that
had been established by the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and theMAFF, while obtaining help from personnel of the two ministries who had many experiences of doing
such works. Thus, the MOE temporarily created the common specifications and other rules(hereinafter referred to as the “Common Specifications”) that were required to implement thedecontamination and other construction works as a direct control project by searching for a way andstarting the decontamination work. After that, they continued to improve the specifications
step-by-step according to the actual conditions of the decontamination sites through a trial and error
process. As a result of these efforts, they established the rules from the framework of the entire
decontamination work to specific construction work implementation methods to a certain extent toenable a quick start of the decontamination works. They also strove to ensure the quality of works.
On the other hand, while we can create design documents for conventional civil engineering workin advance, we have to place an order based on approximate figures for decontamination, because
orders are placed before consent forms are collected. Therefore, we needed to agree on a construction
unit price in advance so that we could adjust an account after implementing decontamination work.
Also, although we need to provide documents about unit price for each decontamination objective at
the time of placing an order, it was difficult to accurately determine the unit prices74 in advance.
Therefore, we estimated the unit prices to allow quick order placement by setting up a team, which
included staff members from the MLIT and the MAFF who had many experiences in placing orders
for civil engineering work, based on the results of decontamination that had been implemented
independently under the model project of the Cabinet Office, as well as by Fukushima Prefecture andmunicipalities. The situation assumed under the model project may not always apply to the actual sitesof decontamination, because there are different conditions such as the existence of newly growing
trees after the earthquake. Therefore, we promoted a PDCA (Plan-Do-Check-Act) cycle energetically,
through changing actual work depending on the condition of the site and providing feedback about theresults. There were also some cases in which we had to do work on the site that had not been specified
in the decontamination guidelines or the Common Specifications. In such cases, the work was done
through trial and error and discussions between the supervising officials from the National
Government and the decontamination business operators. Such knowledge was shared among thesupervising officials to be reflected in the Common Specifications and other documents whenappropriate.
If we try to respond easily to the request of related persons, it may cause a risk of excessive
decontamination. The excessive decontamination would increase the total amount of removed
74Unit price represents a quantified amount of time and effort that is required for a certain task.

75

materials, as well as cause a feeling of unfairness among other related persons. To prevent these
problems, we standardized the judgment on reasonableness for the entire project, and included it as a
new rule in the standard procedures, if it could be theorized or generalized to ensure consistency.
In addition, the National Government improved the environment for decontamination work on thesite, as well as created a good project environment by preparing documents. For example, there is aconcern that the amount of daily life waste disposal and sewage treatment might exceed the existing
disposal/treatment capacity, as a result of a significant number of workers being expected to comefrom other local communities and prefectures. We worked to avoid such a shortage of treatment
capacity by ensuring exchange and confirmation of information between the National Government andlocal governments in advance, without fully leaving the response to decontamination business
operators.

1.3.2. Decontamination to secure safety at an early stage and to facilitate restoration andreconstruction（1） Acceleration of project through sharing information and promoting PDCA cycle
Since early stage securing of safety and restoration/reconstruction was required, we had to start thedecontamination project without sufficient lead-time for conducting sufficient policy preparation.
Therefore, we focused on the PDCA cycle and incorporated information that had not been prepared or
known in the preparation stage moment to moment to compensate for the lack of time at the
preparation stage. A part of such efforts is mentioned in Section 1.3.1.(3).
In large-scale decontamination works that are performed in multiple municipalities, implementationof an individual PDCA cycle only may cause isolated optimization. The system for information
sharing is critical for implementing a PDCA cycle that can contribute to the optimization of
decontamination work as a whole. The governmental organizations that played a central role in theinformation sharing were the Fukushima Environment Restoration Office for Fukushima Prefecture,
Iwate Prefecture and Miyagi Prefecture, and the Kanto Region Environment Office for Tochigi
Prefecture, Ibaraki Prefecture, Gunma Prefecture, Chiba Prefecture and Saitama Prefecture.

（2） Improvement of decontamination speed through setting up of temporary storage sites
In order to perform decontamination work smoothly, it is desirable to secure a disposal site forremoved soil and other materials generated by decontamination work before starting actual work.
There is a limited amount of large land space in Japan that may be used immediately as shown in 1.1.1.
If we started decontamination work after we had secured disposal sites for significant amounts ofremoved soils and other materials, it would take much time and it was clear that the start ofdecontamination would be delayed.
To solve this problem, we decided to secure so called “temporary storage sites” used to store
removed soils and materials temporarily before bringing them to the disposal facility (interim storage
facility), to promote the decontamination work, while making efforts to secure the disposal facility.
However, there were many cases in which the setting up of a temporary storage site was not decided
easily due to a limited amount of land. Many different efforts were made to set up temporary storagesites.
The reasons why the setting up of temporary storage sites was not advanced easily include thefollowing.
Difficulty of setting up sites on public lands
There were sufficient areas of national forests75, and it was not so difficult to form
a consensus about making national forests as candidate sites for temporary storage.
However, many such forests were preserved as protected forests under the Forest
75The area of national forests in Fukushima Prefecture amounts to approximately 400 thousand ha, while theentire area of Fukushima Prefecture is approximately 1 million 400 thousand ha.

76Act and the procedures for cancellation of protected forests were required. It tookmuch time to conduct studies and perform cancellation procedures.
Since the national forests are located in mountainous areas, we need land
reclamation to make them flat. In addition, there are some cases in which
preparation and improvement of access roads are required and the disposal of soil
from such work also has to be stored. As a result, we could not utilize the area ofreclaimed land effectively, and it resulted in taking much time for land reclamation,etc.
Difficulty in forming consensus with residents living in the vicinity
The residents became angry and felt frustrated, because temporary storage sites
were set up not on the premises of TEPCO or national land, but on sites in thevicinity of the residents who were suffering from evacuation and anxieties fromradiation. That became a major obstacle to the formation of consensus.
The residents were worried that the temporary storage site might become a final
disposal site.
There was a concern that accumulation of soil contaminated with radioactive
materials might enhance the impact of radiation.
Residents had a feeling of rejection of storing even contaminated materials thatwere generated outside their own lands.

To address such problems, the National Government, municipalities and decontamination business
operators advanced the following efforts, which led to dispelling the concerns and setting up
temporary storage sites by municipalities.
Seeking candidate lands in the local area
In the case where it was difficult to secure an appropriate temporary storage site
within the national land, this fact was communicated honestly to the municipal
governments and residents and understanding for securing a temporary storagesite in the region was requested. We worked to seek practical solutions jointly withthe local community.
Elimination and mitigation of concerns and frustrations
In response to the opinions that the temporary storage site should be set up within
the premises of TEPCO and the national land, we did not turn down such opinions
immediately, but explained that it was not practical when looking at it objectively,
after considering the practicality of using each premise, and requesting andnegotiating with other governmental agencies in some cases. We also worked toeliminate and mitigate frustrations of the residents by making an in-depth
explanation that to secure the site in their community would result in advancing
decontamination more quickly.
In response to the concerns about the safety of the temporary storage site, we madethe following explanations to eliminate and mitigate concerns of the residents: theoutmost part would be covered by uncontaminated soil; and accumulated soils
would have lower risk once they were accumulated and sufficient safety measures
were taken compared to the case in which removed soil was stored on the site.
In addition, there was also an effort to help the residents realize the safety of atemporary storage site through their building a system for monitoring the
temporary storage site as in the case of Kawamata Town.
In response to the feeling of rejection of storing contaminated materials that weregenerated outside their own lands, we explained patiently that setting up thefacility would result in advancing decontamination more quickly. Also, we sought
the cooperation of heads of district and neighborhood associations, who were closer
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to the residents in terms of psychological distance, and asked them to consider
setting up a temporary storage site in each administrative district.
In the case of Fukushima Prefecture, in response to the concerns that thetemporary storage site might become a disposal facility eventually, the MOE wasin the forefront of the efforts to prepare for interim storage facilities as much as
possible and to appeal with such an attitude to eliminate and mitigate concerns of
the residents.
Transmission of information on actual status
Since the residents did not have an image of a temporary storage site especially in
the initial stage, we worked to create a concrete image of the facility, by providing
explanations with leaflets and holding tours on the site of a temporary storage sitethat was actually set up, in order to reduce psychological resistance against thefacility.
Since decontamination work advanced quickly in the areas where the temporarystorage site was set up, we made appeals with such results to make the residents
recognize the necessity and the importance of the temporary storage site, in orderto accelerate the setting up of a temporary storage site also in the areas where thefacility had not been set up.
Flexible response appropriate for the situation of each area
When it was difficult to set up a temporary storage site by any means, we
responded in a flexible way according to the situation of each area, such as
operation with storage of removed soil and materials on the site, and not sticking
to setting up the temporary storage site as an absolute requirement.

Furthermore, we reduced the amount of generated removed soil and materials through avoiding
excessive decontamination as mentioned above in the first place in order to reduce the amount ofremoved soil and materials that were to be brought into the temporary storage site. We also reduced
the volume of removed soil and materials by cutting, crushing, compressing or burning them.

1.3.3. Project operation with consideration of the maintenance of community and theprotection of rights（1） Maintenance of community
This decontamination project derived from the 1FNPS accident focused on residents’ returning totheir previous lives as early as possible. Therefore, we were required to promote it without damaging
the local communities to ensure later life there, not just to remove contaminated soil and materials.
To achieve this goal, we employed a method to perform decontamination work by an administrative
unit, such as a district; that is to say “Decontamination of the entire community,” not to advancedecontamination work for each related person after obtaining the consent. This decontamination
method has a disadvantage for the residents who agreed on performing decontamination work earlier,because it starts after obtaining the consent from all the residents of an administrative unit, such as the
district.
Despite such a disadvantage, we needed to promote decontamination work focusing on the local
communities that had already existed, given the healthy maintenance of each community after
decontamination, in addition to the fact that there was no sufficient decontamination result without
decontamination for the whole area.
As to setting up the temporary storage site as shown in Section 1.3.2.(2), many residents said thatthey agreed to accept the removed contaminated soil from inside their community, but not those fromother communities. It can be said that the unit of the local community, such as a district, was one of
the important units in Japan to advance decontamination.
This concept was also used in setting evacuation areas. In order to avoid separation of a local
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community or district, we did not use the annual exposed dose as sole criteria for setting a border of anevacuation area. We were careful so that the border of an evacuation area did not divide a district unit,
while making the exposure dose the fundamental criterion.

（2） Protection of rights and consideration of lifestyle
This decontamination project focused on residents’ returning to their previous lives as early as
possible. Therefore, we did a minimum amount of scraping and replacement of roof materials so as to
avoid damages to properties owned by the residents as much as possible. In the case of the residents
engaged in farming, the agricultural land was inseparable from their lives: they had cultivated andnurtured their land over a long period of time. Therefore, when a farming family requested it, we tried
to select an appropriate decontamination method as much as possible to avoid stripping, etc. andworked to maintain the functions of agricultural soils.
Some residents said, “I want a full replacement.” We patiently provided explanations and werecommitted to protect their properties and agricultural lands that were very important for farming
households.
Also, ancestral shrines and garden trees they had grown over years were irreplaceable for the
residents’ lives. If such shrines and garden trees were removed or cut because they were contaminated,that might cause emotional distress to the residents and lead to degradation of quality of their lives.
Therefore, we worked with the residents to coordinate whether decontamination was done or not, as
well as choosing the detailed decontamination method based on a comprehensive judgment on the
degree of decontamination and the importance for the residents, while listening to their opinions.

（3） Obtaining consent securely
In implementing this decontamination project, we adhered to obtaining consent from the residents
before starting decontamination. We were determined not to perform decontamination forcibly,
ignoring the intention of the residents.
This was very important not only in terms of the importance of obtaining consent from the residents
from a viewpoint of protecting the right of the residents76 as mentioned in (2) above, because
decontamination could damage or change the properties and agricultural lands of the residents, butalso in terms of sharing and agreeing on the decontamination plan with the residents, because there
were different objectives and methods of decontamination.
Therefore, we obtained the consent of the residents while giving them in-depth explanations andpreparing detailed drawings and materials about decontamination procedures for eachdecontamination objective.
On the other hand, as mentioned above, there are currently several tens of thousands of displaced
people from the evacuation area and more than one hundred thousand including those that fled fromoutside the evacuation area. To obtain residents’ consent to decontamination, it is necessary to identify
related persons who have the rights over targets of decontamination and obtain consent regardless ofwhether they are living there or have evacuated the area. However, there are a great number ofdecontamination targets: the number of residences to be covered by decontamination solely amounts
to from several tens of thousands to several hundred thousand. Especially for the Special
Decontamination Areas, where all the residents have evacuated, we need to identify the number ofrelated persons by checking with registry books and other materials, then identify where they haveevacuated to and explain the current situation and the method of decontamination to them to obtainconsent. Also, in the case that one person owns multiple land plots or buildings, name-baseaggregation is required to organize the data. As a result, a great amount of manpower was required toobtain their consent.
Moreover, we could not always obtain the consent after a one-time explanation/discussion. There
were many cases in which we finally obtained the consent after we had listened carefully to the76In addition to obtaining consent from residents on the possibility of damages to their properties in theprocess of implementation of agreed-on decontamination methods, we needed to agree on the conditions of
their properties before decontamination so that we could confirm whether damages and loss discovered
after decontamination had been caused by decontamination work or not.

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requests of the residents, considered such requests and answered their questions again and again.
Especially in the Special Decontamination Areas from where the residents had already evacuated, it
was more difficult to obtain the consent, because the residents could not confirm whether there wasany inappropriate decontamination work or damage to the buildings for themselves. Therefore, we
confirmed their consent on the site and allowed them to be present at the decontamination to observe
decontamination work so that the residents could confirm the work with their own eyes. We also
provided instruction and education to decontamination business operators and workers, who would
obtain the consent from related persons, to respond to such persons sincerely so that they could build a
relationship of trust with them.
Although those efforts were made, the degree of consent varied by individual and by area. As aresult, the progress of decontamination varied by area, and the areas in which decontamination wasunderway and those in which it was not were distributed in a patchy fashion.

1.3.4. Careful response with consideration for residents’ position and feelings
Anxieties and concerns of the local residents are not always related to decontamination. Especiallyin the Special Decontamination Area, the residents did not necessarily have a positive attitude toward
discussing decontamination solely, because the review of the area that served as a base for thedecontamination plan was related to the compensation criteria. Therefore, we made careful responses
giving thought to situations and feelings of residents of the area, such as bringing staff members who
could provide explanations about the review of the area and compensation when we had a briefing
session about decontamination.
Also, the residents had a feeling of non-acceptance toward effluent water, as they had an image that
contamination was also transferred when water flowed from the premises of their residences to outside,although it was unlikely that effluent water generated as a result of decontamination in the Intensive
Contamination Survey Area had a higher level of radioactive concentration. Therefore, we took
necessary measures in response to the request of the residents, such as recovery of effluent water.
Furthermore, we also gave consideration to their feelings about visiting their residences: In theseasons when there were many requests for overnight stay, such as the year-end and New Yearholidays and the Bon period for visiting their ancestors’ graves, we also conducted decontamination
prior to these periods.
In addition, the fact that many decontamination workers come to the community from outsidemeans an increase of strangers in the community to the local residents, and they are likely to beconcerned about the change of the community’s atmosphere, deterioration of public security andgeneration of traffic jams. To address such concerns, we made many efforts to build a relationship oftrust between the local residents and the decontamination workers.

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