Progress on Off-site Cleanup Effort on Fukushima Nuclear Power Plants Accident Yutaka Kawakami
Amount of Disaster Waste (Coastal Area) Total 26,410,000 ton Prefecture Amount of Disaster Waste Fukushima 3,370,000 ton Miyagi 17,770,000 ton Iwate 5,270,000 ton As of Sep. 30, 2013 2
Current Status of Specific (Designated) Waste (over 8,000 Bq/kg ) (as of August 31rd, 2013) 3
Comparison of Released Radioactivity, Chernobyl and Fukusima Chernobyl NPP, Fukusima Daiiti NPS, No,4 Reactor （７） Total of Unit 1 to Unit 3 （８）（９） I-131 Cs-137 I-131 Cs-137 Radio nuclides Core inventory 3,200 280 6,100 710 (10 15 Bq) Released radioactivity ~1,760 ~85 160 15 （ 10 15 Bq) 50~60 20~40 2.6 2.1 Release rate (%) (7) OECD/NEA(2003 )”chapter II The release, dispersion and deposition of radionuclides. Chernobyl: Assessment of radiological and health impact; 2002 ” (8) ,(9) NISA report 4
The Point at Issue on The Contaminated Waste Nuclear regulations are only applied for nuclear facility and facility related materials. “Act on Special Measures concerning the Handling of Pollution by Radioactive Materials” was legislated. Regulations on radiation protection was corresponded by amendment of “Ordinance on Prevention of Ionizing Radiation Hazards”. This ordinance is a part of the “Industrial Safety and Health Law” and is aimed for protection of radiation workers. Huge amount of contaminated waste. Widespread of radioactive contamination. Progress on the remediation activities, a large amount of contaminated waste which are removed soil and other materials including ash from incineration of combustible waste are generated. 5
Act on Special Measures concerning the Handling of Pollution by Radioactive Materials （ Enacted Aug. 2011) Objective On the special measures concerning environmental pollution by radioactive materials, by establishing measures to be implemented by the national government , local government and nuclear operators, quickly reduce the influence on human health and living environment due to the contamination of environment. Responsibilities The national government ： implement necessary measure in view of social responsibility on promoting the nuclear policy. Local government: play an appropriate role through cooperation to the national government measures. Nuclear operators: implement necessary measure in good faith and cooperate with policy of the national government and local government .. Institution Establishment of basic policy Minister for the environment establishes measures on environmental pollution by radioactive material and requires cabinet decision . Establishment of standard Minister for the environment establishes criteria for treatment of soil and waste contaminated by radioactive materials. Implement of monitoring and measurement The national government arranges and implements unified monitoring and 6 measurement to grasp the situation of contamination of environment immediately .
Framework of Decontamination Legislation for Promoting Decontamination The Act on Special Measures Concerning the Handling of Radioactive Pollution come into the force on January 1, 2012. Based on this Act the followings are carried out Planning and implementation of decontamination work Collection, transfer, temporary storage, and final disposal Special Decontamination Area 11 municipalities in (former) restricted zone or planned evacuation zone (less than 20km from the NPS, or annual cumulative dose is more than 20mSv ) Decontamination is implemented by the national government Intensive Contamination Survey Area 100 municipalities in 8 prefectures , in which over 0.23 μSv/hour of air dose rate (equivalent to over 1 mSv/Year of additional dose rate) is observed, were designated. Decontamination is implemented by each municipality. The national government will take financial and technical measures. 7
Special Decontamination Area and Intensive Contamination Survey Area ・・ Intensive Contamination Survey Area ・・ Special Decontamination Area Fukushima Pref. Iwate Fukushima City Miyagi Fukushima Dai-ichi Koriyama NPP City Fukushima Dai-ichi Fukushima NPP Iwaki Tochigi City Gunma Ibaraki Saitama 20 ｋｍ Chiba 8
Decontamination Policy for Special Decontamination Area Policy in FY2012 and 2013 Decontamination should be implemented taking into account the level of air dose rate. Area less than 20mSv/year ： Aiming to reduce additional exposure dose to less than 1mSv/year as long-term goal. Area from 20 ～ 50mSv/year ： Aiming to reduce exposure dose in residential and farmland area to less than 20mSv/year. Decontamination work in all municipalities in the Area has been uniformly scheduled to be completed within 2 years, assuming the securing of temporary storage sites and consent of land owners, etc. In the case of areas more than 50mSv/year, demonstration projects will be implemented. Lessons learned will be taken into consideration in future decontamination policy. Policy Review at Sep. 2013 Decontamination work will be implemented in cooperation with reconstruction measures depending on the situation of each municipality. Additional measures for further progress will be conducted. 9
Decontamination Activities Guideline for Guideline for Guideline for Guideline for Guideline for measurement of decontamination collection and storage of decontamination radio activities in transportations techniques recovered soil contaminated of recovered soil area 10
Before & After the Decontamination Work (Tamura City ) Before Before Before Before After After After After 11
Decontamination Activities ( Tamura City ) Wiping off rooftop and walls Wiping off a gutter High pressure water cleaning of a drain pipe High pressure water cleaning of Mowing and removal of sludge Removal of crushed stones and paved road topsoil, and cover with clean soil 12
Decontamination Activities Packages and Transportation Criteria for Contaminated Soil Punching bag sheet Plastic case Flexible Drum container bag Below 100 μSv/h 13
Effect of Radiation Dose Reduction by Decontamination Work (Air Dose Rate at the height of 1m above ground) Tamura City ・・・ Before the decontamination work Measurement Points ・・・ After the decontamination work and more Ambient Dose Rate at the height of 1m above the ground(µSv/h ) ※ The measurement was taken before and after the decontamination work so that natural attenuation effect after the work was not included. Measurement period before the decontamination work: July 25, 2012 ～ May 23, 2013 Measurement period after the decontamination work: August 7, 2012 ～ May 30, 2013 14
Flow Chart of The Contaminated Disaster Waste (Fukushima Pref.) Specific Waste 15,000,000t~31,000,000t ~500,000t ~110,000t Soil and Waste Waste in Designated Area Designated Waste Generated by Decontamination More than 8,000Bq/kg Combustible Non-combustible less than More than Waste Waste 8,000Bq/kg 8,000Bq/kg Incineration Same Treatment Temporally Storage as Designated Waste Same Treatment less than More than Volume reduction as Outside of 100,000Bq/kg 100,000Bq/kg Designated Area Interim Storage Controlled Landfill Monitoring is implemented Final Disposal by the state 15
The Policy on Decontamination in Specified Decontamination Area (The point of roadmap) Start of transfer to interim storage Interim storage facility will established only in Fukushima prefecture where huge amount of soil and waste generated by decontamination activities. (transfer from outside of the prefecture is prohibited) Besides Fukushima prefecture, waste management is promoted in each prefectures. Requirement from decontamination activity, interim storage facilities will be operated for 30years, and final dispose of the waste will be conducted 16
Temporally Storage of Contaminated Soil Packages Fence Water Shield Cover Soil Fence Sandbag Collective Tank Monitoring System 17
Illustration of Interim Storage Facility ISF will be consisted of facilities with various functions ① Storage Facility ② Emplacement & Segregation Facility ③ Volume Reduction Facility Admin Office ④ 24-hour monitoring Equipment( placed in several points, not specifically Buffer Green Zone indicated in the figure) ⑤ R & D Facility ⑥ Public information Center Scale of the whole facility （ estimation ） Total storage volume ranges between 15-28 million ㎥ , which is 12-23 18 times big as a baseball stadium( approx. 1.24million ㎥ ) 18
Conceptual Structure of Interim Storage Facility Type-I Soil Storage Type-II Soil Storage Waste Storage Facility Facility Facility Soil and other materials Main substances that do not risk polluting Soil and other materials for storage public water area and exceeding the condition (Radioactive Waste groundwater with shown in left column cesium radioactive cesium (More than 8,000Bq/kg ) concentration) ( 8,000Bq/kg or less ） Seepage control and other Measures to infrastructure prevent water (Seepage control sheet － Package seeping into and other infrastructure ground water or low-permeability soil layer) 19 19
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