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  • Current Status of Fukushima Daiichi Nuclear Power Station

    -Efforts for Decommissioning and Contaminated Water Management-

    Agency for Natural Resources and Energy, METI July, 2019

  • 1

    1.Progress on Fukushima Daiichi Decommissioning

    2.Overview of Water Management

    - Countermeasures for contaminated water

    - Issue of “ALPS treated water”

    3. Environmental Monitoring

    4. IAEA review mission

    5. Information Portal site

    < Outline >

  • Introduction: Where is Fukushima Daiichi?

    Approx. 250km  from Tokyo

    Unit 1-4

    Approx. 2km 

    2

  • At the time of the nuclear accident Today

    Overview : Current status of Fukushima Daiichi NPS

    • The reactors of Fukushima Daiichi NPS are being kept in stable condition.

    The accident cut off the water supply to the reactors. As a result, the fuel generated heat, and hydrogen explosions occurred.

    Reactors are being kept stable.

    3

  • ◇ Fukushima Daiichi Decommissioning is a continuous risk reduction activity to protect the people and the environment from the risks associated with radioactive substances by:  Removing spent fuel and fuel debris from the Reactor Building  Reducing the risks associated with contaminated water and radioactive waste

    ◇ Government of Japan published “Mid-and-Long-term Roadmap”  Setting overall framework and major milestones for decommissioning

    ◇ Safe and steady decommissioning is a prerequisite for reconstruction of Fukushima  Evacuation orders were lifted gradually around the site

    1-1.Decommissioning of TEPCO Fukushima Daiichi NPS

    4

    Water

    Fuel Debris

    Spent fuel (Spent fuel pool)

    Fuel that remains after its usage for power generation. Continuous cooling is needed to suppress the heat

    Fuel that has melted and solidified by the accident. Continuous cooling is needed to suppress the heat

    Contaminated Water Management

    Radioactive Solid Waste Management

    Dec. 2011 Nov. 2013(Unit4) Within 2021Now

    Phase 1 Until start of fuel removal

    from SFP(within 2 years)

    Phase 2 Until start of fuel debris

    retrieval (within 10 years)

    Phase 3 Until completion of decommissioning

    (30-40 years)

    Decommissioning Road Map

    Efforts for stabilization Cold shutdown state drastic reduction of release of radioactive material

    Watch the video!

  • “significant progress has already been accomplished to move Fukushima Daiichi from an emergency situation to a stabilized situation.” (IAEA review mission / January 31, 2019)

    No fuel debris

    5

    1-2.Progress and Milestones on Fukushima Daiichi Decommissioning

    Started rubble removal from the operating floor:

    (Jan. 2018-)

    * Start spent fuel removal: (FY2023-)

    Started investigation of the operating floor:

    (July 2018-)

    * Start spent fuel removal (FY2023-)

    Started spent fuel removal: (April 2019-)

    * Complete fuel removal (-FY2020)

    Completed fuel removal (Dec.2014)

    Achieved investigation inside of PCV: in Mar. 2017 in Jan.-Feb.2018/Jan.2018/Feb.2019 in July 2017

    * Decide 1st implementing Unit and method (in FY2019)

    * Start Fuel debris retrieval (within 2021)

    Completed construction of frozen-soil wall (Sept. 2018) Completed storage of all treated water in welded-joint tanks (Mar. 2019)

    * Reduce rate of arising contaminated Water to about 150 m3/day (within 2020) * Complete removal of stagnant water in buildings(other than reactor building) (within 2020)

    * Establish technical perspective on measures of treatment/disposal and on safety (around FY2021)

    Major Milestones and current situation of Unit 1-4 (*milestones of Mid-and-Long-Term Roadmap)

  • 0

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    1-3.Impact on the Surrounding Environment

    • The environmental impact on the site and surrounding area have been significantly reduced.

    Guidance value recommended in the WHO Guidelines for Drinking water quality (10Bq/L)

    (Bq/L)

    There has been no effect of the radioactive material (dusts etc.) to the outside in the

    course of decommissioning work.

    Whole map of Fukushima Daiichi Nuclear plant

    Sea

    Air Ra

    di at

    io n

    do se

    r at

    e (

    m Sv

    /y ea

    r)

    10,000 over

    6

    Near the south  discharge  channel

    N

    Evaluation of annual exposure dose at the site boundary due to radioactive materials (cesium) from the reactors buildings of Units 1-4

  • 7

    Iitate

    Katsurao Namie

    Futaba

    Areas where Returning is Difficult(ARD) 

    Preparation Area for lift of Evaluation order

    Habitation Restricted Area

    Area in which evacuation orders were lifted

    Coastal area in Fukushima Pref.

    Minami ‐soma

    Tamura

    Kawauchi

    Naraha

    Date

    Hirono

    Kawamata

    Fukushima  Daiichi NPS

    Okuma

    Tomioka

    Iwaki

    Ogawara, Chuyashiki districts Lifted on April 10th, 2019

    Diagram areas under evacuation  orders

    (as of April 10th, 2019)

    Explanatory notes

    ・Ogawara district: Habitation Restricted Area

    ・Chuyashiki district : Preparation Area for lift of  Evaluation order

    Evacuation orders were lifted on April 10th, 2019.

    N

    (ref.) Lift of evacuation orders

  • Waterproof pavement

    2-1. Overview of Water Management - Multilayered Countermeasures -

    8

    Sub-drain

    Land-side impermeable wall (frozen-soil wall)

    Sea-side impermeable wall

    Groundwater -bypass

    Store in tanks after purification ( )

    ◇ Contaminated water is generated by groundwater and rainwater which are flowing inside the unit 1 to Unit 4 buildings of the NPS.

    ◇ Comprehensive set of countermeasures have taken by the TEPCO and GOJ:  To reduce the rate of arising contaminated water; 490 m3 (FY2015)  170 m3 (FY2018)  To prevent the leakage of contaminated water from the buildings;

     Water level inside the buildings has been maintained at levels lower than groundwater outside  To purify the contaminated water from the buildings (“ALPS treated water”)  To safely store the “ALPS treated water” which was purified by several purification

    equipment to remove most of the radionuclides except Tritium

  • 2-2. Overview of Water Management - Effectiveness of measures to date -

    9

    1. Rate of arising contaminated water is greatly reduced

    2. Meets drinking water standard

    *The concentration of radioactive materials in the sea around the site refers to the Cs-137 level near the south discharge channel

    *The international standard for drinking water quality is 10Bq/L

    3. A level of 1 mSv/year is attained at the site boundary

    Apr. 2015 to Mar. 2016

    Apr. 2018 to Mar. 2019

    170㎥

    Amount of contaminated water generated (daily average)

    Concentration of radioactive materials in the sea around the plant

    Estimated doses from facilities at the south side of the site

    Thanks to purification treatment of the water stored in tanks, estimated doses at the south side of the site decreased.

    9.76 (mSv/year)

    Mar. 2014

    Approx. 10,000Bq/L

    Mar. 2018March 2011

    Less than the detection limit* (approx. 0.6Bq/L)

    Dec. 2018

    490㎥

    0.9

  • 2-3. Overview of Water Management - Storage of ALPS treated water -

    Status of ALPS treated water

    Volume of water stored in tanks  About 1.14 million ton(as of June 2019)

    Projected tank volume About 1.37 million ton (end of 2020)

    Generation rate of ALPS treated  water About 50,000‐80,000 ton/year

    【ALPS treated water tanks spreading at 1F site】

     At present, ALPS treated water (≠contaminated water) is being kept stored on site

     Currently, tanks continue to increase. The installation area of the tanks occupy much of the southern half of the site.

     The current tank capacity per the construction plan is 1.37 million tons. The available site area for building new tanks is approaching the limit. (ref. northern half of the site is planned to be the solid radioactive waste storage facilities area)

    10

  • 2. Technical evaluation of disposal methods by the Tritiated Water Task Force

     METIʼs “The Tritiated Water Task Force (2013-2016)” assessed the regulatory feasibility, technical feasibility (including monitoring to ensure safety), period and cost of 5 final treatment methods ; (1) geosphere injection, (2) discharge to the sea, (3) vapor release, (4) hydrogen release, and (5) underground burial.  All cases are examined on the premise that there is no scientific impact on the human habitant.  Verification project showed that the separation technology for tritium cannot yet put into use.

     The issue of handling ALPS treated water has been discussed in “The Subcommittee on Handling ALPS Treate

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