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1-1. Overview of the subdrain water treatment facilities. Water treatment facilities including subdrain consist of water collecting equipment, purification equipment, and transfer equipment.

Subdrain water collecting equipmentEquipment to pump up groundwater from subdrain pits installed around the turbine buildings of Units 1 to 4 and the water collecting equipment (groundwater subdrain) to be installed inside the impermeable wall on the seaside.

Subdrain purification equipmentEquipment to remove existing radioactive nuclides (except for tritium) contained in pumped up groundwater to the lowest concentration possible.

Subdrain transfer equipmentEquipment to transfer the treated water having undertaken sampling during storage in a tank.

Water collecting tank

PSubdrain and

groundwater drain of Units 1 to 4

Water collecting

tank/ transfer pump Sampling tank

Adsorption tower

Pre-treatment

filterAdsorption

tower

・・・

Pre-treatment

filterPurified water transfer pumpTreatment

equipment Supplying tank

P

*1

Subdrain purification equipment

Subdrain water collecting equipment

Subdrain purification equipment

Subdrain transfer equipment

Designed flow: 1,200m3/ day/ system

Start of the verification test for purifying performance of the subdrain water treatment facilities at Fukushima Daiichi Nuclear Power Station

August 11, 2014Tokyo Electric Power Company

*1 Where to be transferred will be reflected on once the specific design is determined.

2

Layout of components in the subdrain purification equipment building.

1-2. Layout of subdrain water treatment facilities

Subdrain purification equipment

Main anti-earthquake bldg.

Subdrain water collecting equipment

At the location of O.P.+40m, subdrain purification equipment building (approx. 46 m x approx. 32 m) will be built.

Subdrain transfer equipment

3

2-1. Verification test for purifying performance

PurposeIn response to a partial completion of the subdrain water treatment facilities, a test* to verify the performance of removing radioactive nuclides (except for tritium) will be performed on the actual equipment. (* Verification test for purifying performance)

Actions [1] Pump up groundwater from the 14 subdrain pits having been installed to be mixed in the

water collecting tank. [2] Verify the removal competence by comparing two concentrations of radioactive nuclides

sampled respectively at the inlet and the outlet of the subdrain purification equipment. [3] Treated water having passed through the purification equipment will be stored in the

sampling tank located at the downstreem.

4

2-2. Verification test for purifying performance (subdrain water collecting equipment)

Equipment to use for verification test for purifying performance (outlined in red) Subdrain pit 14 pits (14 out of 42) Relaying tank 2 tanks (2 out of 5) Water collecting tank 1 tank (1 out of 3)

：既設ピット

：新設ピット

：中継タンク、中継タンク移送ポンプ

：配管

：配管（浄化性能確認試験にて使用）

集水タンク

中継タンク①

中継タンク②

中継タンク③中継タンク④

中継タンク⑤

＃１ Ｔ／Ｂ

＃１Ｒ／Ｂ ＃２

Ｒ／Ｂ

＃２ Ｔ／Ｂ

＃３Ｒ／Ｂ

＃３ Ｔ／Ｂ

＃４Ｒ／Ｂ

＃４ Ｔ／Ｂ

Water collecting tank

Relaying tank [2]

Relaying tank [1]

Relaying tank [5]

Relaying tank [4]Relaying tank [3]

Newly installed pit

Existing pit

Relaying tank/ transfer pump bet. relaying tanks

Pipe line (used for the verification testPipe line

5

2-3. Verification test for purifying performance (scope of use)

Equipment to use for verification test for purifying performance (Outlined in red) Subdrain purification equipment 1 system (B system, 1 out of two) Sampling tank 1 tank (1 out of 8)

集水タンク

前処理フィルタ

サブドレン他浄化装置

吸着塔

前処理フィルタ

吸着塔

P

処理装置

供給タンク

P

処理装置

供給ポンプ

P1B 2B 3B 4B

処理装置

加圧ポンプ

1B 2B 3B 4B 5B

1A 2A 3A 4A P 1A 2A 3A 4A 5AP P

サブドレン他移送設備サブドレン集水設備

・・・

浄化水移送

ポンプ

P

P

P P

浄化水攪拌

ポンプ

P

P

*1 Under designing for where to be transferred.

Water collecting tank

Pre-treatmentFilter

Subdrain purification equipment

Adsorption tower

Pre-treatmentFilter Adsorption tower

Water collecting tankTransfer pump

P

Treatment deviceSupplying pumo

P P1B 2B 3B 4B 1B 2B 3B 4B 5B

1A 2A 3A 4A P 1A 2A 3A 4A 5AP P

Subdrain purification equipment Subdrain transfer equipmentSubdrain water collecting equipment

Sampling tank

・・・

Treated water transfer pump

P

P

P P

Treated watersteering pump

P

P

*11～4号機サブドレンピット

P

P P P P P

Relaying tank

Units 1 to 4Subdrain pit

P

PP PP PP PP PP Relaying tankTransfer pump

Treatment devicePressure pump

Treatment deviceSupplying tank

6

3-1 Overall schedule

Subdrain purification equipment

Subdrain pipe line,Relaying/water collecting tanks

SubdrainExisting pit

SubdrainNewly installed pit

62015

109875432112111098

Sub

drai

n w

ater

col

lect

ing

equi

pmen

t

Major process

2014

Excavation for new pit installation

Floating article removal form existing pits

Demolition of fixed facilities and installation of foundation, pipe line and tanks

Start up construction▼

Preparatory work

Yard preparation (rubble removal, etc.)

(Water investigation)

Bldg.

Note: The schedule is subject to change in the course of adjustment with construction works.

Passing water examinationFacilities

Site preparation Foundation Steel frame, exterior walls, roof Finish up

Subdrain transfer equipment

Purification equipment installation

Transfer equipment installation/passing water examination

Filed implementation plan 12/18▼

Groundwater drain

Excavation for new pit installation

Pipe/tank installation

Approved implementation plan(Subdrain water collecting equipment

and purification equipment)8/6▼

Start up pumping up groundwater8/12▽

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3‐2. Schedule on Verification test for purifying performance (incl. analysis)

June July August September October to 

Beg. Mid. Late Beg. Mid. Late Beg. Mid. Late Beg. Mid. Late

The whole

Before‐use Inspection

Water collecting/purification equipment

Analysis *

Installation works (System B)

Passing water examination with filtered water

▽8/20 Verification test for purifying performance

Analysis (Cs, gross β, and H‐3)

Detailed analysis (in‐house)

Detailed analysis (external, third parties)

Installation works (System A)

PPPWater 

collecting tank

Water collecting tank

Transfer pump

Supplying tank

Treatment device

Supplying pump

Pre‐treatmentfilter

Treatment device

Pressure pump

Adsorbent Sampling tank

Water collecting equipment

Purification equipment

Water collecting equipmentexamination range for passing 

water with filtered waterPurification equipment

examination range for passing water with  filtered water

Scope of verification test for purifying performance

1200m3 1200m3

P PRelayingtank

Relaying tankTransfer pump

12m3 30m3

▽8/12  Start up of groundwater pump up from subdrain pits

▼ Implementation plan approved on 8/6

+ analysis results will be reported in an timely manner.

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[Reference] Subdrain purification equipment

System composition outline

Floa

ting

artic

les

rem

oval

Pre-treatment filter

Subdrain/ groundwater drain of

Units 1 to 4 Cs

roug

h re

mov

al

Sr R

ough

rem

oval

Cs/

Sr a

dsor

bent

Cs/

Sr a

dsor

bent

Cs/

Sr a

dsor

bent

Sb

abso

rben

t

Hea

vy m

etal

ads

orbe

nt

Treatment device

Supplying tank Floa

ting

artic

les

rem

oval

Pump

Pump

Adsorbent tower

To s

ampl

ing

tank

s

Subdrain purification equipmentSubdrain water collecting equipment

Bird’ eye view (Image)

The same with the system mentioned above.

１ ２ ３ ４ １ ２ ３ ４ ５

*1 Filter which absorbs Cs or Sr, or both of Cs and Sr depending on water quality.Verification test for purifying performance is planned to follow the below composition of towers.

1st tower: Sr adsorbent2nd tower: Sr adsorbent3rd tower: Cs&Sr adsorbent

Water collecting tank

*1*1*1

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[Reference] Main conditions/ specifications for subdrain water treatment facilities

*1 Index indicating a degree to which radioactive materials (contamination sources) are removed through decontamination treatment.*2 Estimated value for major nuclides

Item Contents

Design throughput (100% flow)

1,200m3/day X 2 systems (purification facilities)

Radioactive concentration

at the exit of facilities

Ｃs-137： １Bq/L or less *2

Sr-90 ： １Bq/L or less *2

Decontamination coefficient *1

Cs-137： 104 or more *2

Sr-90 ： 103 or more *2

Seismic class Class B

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[Reference] Installation construction of subdrain water treatment facilities

Newly installed subdrain pit N1 (excavation completed) No 1 relaying tank installation

Inside the building Sampling tank installation

Water collecting tank installation

Exterior of the building (Southeast side)