ML12340A603

Official Exhibit - NYS00422C-00-BD01 - Interim Report (Main Text), Investigation Committee on the Accident at Fukushima Nuclear Power Stations of Tokyo Electric Power Company (Dec. 26, 2011)

ML12340A603
Person / Time
Site:	Indian Point
Issue date:	12/26/2011
From:	Tokyo Electric Power Co
To:	Atomic Safety and Licensing Board Panel
SECY RAS
References
RAS 22873, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01
Download: ML12340A603 (48)

Text

United States Nuclear Regulatory Commission Official Hearing Exhibit NYS00422C Entergy Nuclear Operations, Inc. Submitted: June 29, 2012 In the Matter of:

(Indian Point Nuclear Generating Units 2 and 3) c:..\,.~""R REGlI~;. ASLBP #: 07-858-03-LR-BD01

• l~'~...

Docket #: 05000247 l 05000286 Exhibit #: NYS00422C-00-BD01 Identified: 10/15/2012

• 0 Admitted: 10/15/2012 Withdrawn:

~ ~

....,,1-

? ~

0.... Rejected: Stricken:

• • • • il Other:

educational racilities that implemented the exposure reduction method ror the soil in their schoolyards in schools \vhere air radiation dose rates exceeding 1JlSV/11 ,,,,ere detected.

On August 26, MEXT indicated the level that students would be exposed to should be ImSv/year or less L.'1 schools after tl-}e su.f11. .rner

. vacation ended a'1d tl-}e air radiation level rate of l~Sv/h or less as the guide to meeting the criterion. Tne Ministry also suggested that, although it is not required to restrict outdoor activities even if the air radiation dose rate exceeded the guide~ it "vas preferable that measures such as decont3.J.Ttination "vere taken promptly, and it was important to identifY and decontaminate the area where high radiation doses were detected locally.

Additionaily, after April l4, MEXT consecutively monitored me schoolyards of 52 schools where relatively high air radiation dose rates (3.7~Sv!h or higher) had been detected during t~e monitoring performed by Fukushima Prefecture from A.pril 5 to 7. A. .s a result air radiation dose rates of3.g~tSv/h or higher were detected in 13 facilities on April 14, however. an air radiation dose rates or 3.8~Sv!h or higher was not detected in anv school after tvlay 12. TIle highest level on August 25 \vas O.8~LSV/1l111.

h. C!*iteria for disaster waste disposal An extremely large amount of disaster waste was produced by the earthquake and tsunanu. The Waste Management and Public Cleansing Act does not apply to waste that is contrurtinated vvith radio&.'1:ive materials (Article 2 Clause 1 of the Act) an.d t~ere is no other law that regulates the disposal of disaster waste contaminated \vith radioactive materials. 1I2 Therefore the Ministry of the Environment established the criteria for disposai in consultation wim the ivlinistry of Heaim, Labour and Welfare and METI.

On May 2, the Ministry of the Environment decided in consuitation with the related 111 The air radiation dose rates "vere measured 1m above t.~e 5'<folh~d in jurjor pjgh schools and 50cm above the ground in elementw-"Y schools, preschools Wid nursery schools.

m The "Act on Speci8l Measures Conceming Environmental Contami.l1ation Caused by Radioactive Materials Discharged by the Nuclear Power Station Accident Caused by the Tohoku district olr- the Pacilic Ocean Earthquake on March 11, 2011" was enacted on August 26 as a nlakesrdft act fOi t.t..dS gap (t.1.e piovision ielated to \vaste disposal Calne into effect on J3.J.lUill*'Y 1, 201 2) This Act stipulates that the Govemment shall dispose or waste contaminated with radioactive materials originating from the accident at the Fukushima Dai-ichi f-.ll'S.

-888-OAGI0001550_00100

ministries and agencies to conduct an investigation into the concentration of radioactive 11laterials in the disaster waste in the Hamadori and NakadOll regions of Fukushima Prefecture, Lhen continued further studies based on the results of this investigation and presented the "Disposal Guideline lor Disaster Waste in Fukushima Prefecture" on June 23.

In this guideline, the Ministry indicated several criteria such as: the incinerated ash 01 the disaster \'vaste may be disposed orin la"'1cif111 when the concentration oCradioactive ceSiWl1 is 8.000Bq/kg or less: when the concentration is between 8.000Bq/kg and IOO.OOOBq/kg.

preferably the ash should be stored temporarily until the safety of disposal is confirmed:

and preferably the ash should be stored \\'ith1n a facility that is capable of shielding radiation ,,,,hen the concentration exceeds lOO,OOOBq/kg.

Because radioactive materials of high concentration were detected in the incinerated ash of the waste even in prefectures other than Fukushima, the Ministry of the Environment presented the "Present Guideline [or ~,,1casurclncnt w"'1d Hlli'1dling of Incinerated Ash in General Waste Incineration Facilities" as a standard for the handling of the incinerated ash according to the disposal policy for the disaster waste in Fulmshima Prefecture to 16 pnfedmes in Ule TuhuKll, K;mtu auu uiher wslrids un jWle 28.

On August 31, tl-te l\1irllstry of tl-te Erlviromnent indicated a po!iCj" tl-tat peffilitted tl-te disposal of incinerated ash with a concentration of radioactive cesium in the range of 8,OOOBq/kg to 100,000Bq/kg in landfilL which had been previously been considered prererable to be stored tempora.--ily* until L"'1e safety or its disposal \vas conrinllcd, on condition that: (1) puhlic water area, and groundwater should he protected Irom contamination by radioactive cesium, and (2) the landfill sites should be placed under iong-term controi induding restrictions on the use of the site.

c. Sewage sludge On April 30, a high concentration of radioactive cesium was detected in sewage sludge in FukusrIiITw Prefecture. After tlris \",:as reported, iLlspections for radioactive ITwterials in sewage sludge V~iere conducted in other prefecture:; and similarly high concentrations \vere detected.

Tnere are two types of sewage treatment: (1) combined sewerage (which collects the

-8R4-OAGI0001550_00101

sewage and rainwater in the sarne sewage pipe for transfer to a sewage trealment plant),

and (2) separate se\verage (\vhich collects the sewage and raill\Vater in sepm-ate pipes that transfer onJy the se\vage 10 a se\vage treatlnen! plan! ffi1d Ie! the raifl\\.'aier 110\\' into a river and/or the ocean). The high concentrations were detected in the sludge in the sewage treatment plants 01 the combined sewerage system. Tnereiore it is beiieved that the high concentrations oCradioactive materials \vere detected because of the dispersed radioactive materials which were carried bv the rainwater to the sewage treatment plants and concentrated there.

On IvIay 12, the NERHQ presented "Concept of Provisional Handling of Selvage By-product.s in Fukuspjw2 Prefecture" to indicate iliat the dehydrated sludge \vith a relatively high concentration exceeding lOO,OOOBqikg should be stored appropriately after volume reduction in the prefecture whenever possible.

On JUi'1C 16, at L.~c request of oL.1.cr prefectures to indicate a criterion for L.1.C dchjidratcd sludge, the NERHQr presented "Provisional View on By-products of Sewage Treatment and the like in which a High Concentration of Radioactive Materials is Detected" to imllGll.e thal: the sluuge in which rawuacLi ve cesiwIl uver lOO,OOOBtj/kg has been uelecLoo preferably should, "lhere possible, be stored in a f::1Cility tl-tat is capable of shielding radiation within the prefecture from where the sludge originated; sludge with radioactive cesium of 8,OOOBq/kg or iess may be disposed of in iandfiil on certain conditions, such the landfil1 site not be used Cor residentia1 purposes; a."'1d sludge vvith radioactivc cesium in the range orS,OOOBq/kg to IOO,OOOBqlkg may be disposed orin landlill under certain control conditions.

d. Disposa! site for s~Jli/age sludge ?Jld the like The Nuclear Emergency Response Center and the Ministry of the Environment indicated the disposal criteria for dehydrated sludge and incinerated ash containing radioacti\'e uULteriws. Hovvever, their disposal illid reuse have not progressed because of opposition rrom the inhabitants around the disposal sites and r~iection from the disposal operators, therefore some sewage treatment plants and waste incineration facilities are still

-8Rfi-OAGI0001550_00102

ll3 being forced to store the sewage sludge and incinerated ash that has not been accepted .

a. Ctitetia for bathing areas On June 7, the Ministt} or the Environment began to deliberate on guideline regarding the use of bathing areas in response to the directive ITom ChierCabinet Secretuiry EdarlO.

On June 14. the Ministry held the Roundtable Conference for Radioactive Materials in Bathing Areas to hear from experts on radioactive materials. On June 24, on the basis of advice fr0111 the NSC japan, the lvIinistlY presented a guideline about radioactive materials in bnth.ing areas that indicated: (1) [!1(lioactive cesium of 50Bq/liter or less nn.d [nliioactive iodine of 30Bq/liter or less should be considered as the provisional b'1lideline for the summer of 201l; (2) managers of bathing areas preferably should monitor the concentration of radioactive lTlat....L~als in L.~c \vaLcr and display L.~c result on a placard or some other means: (3) managers and users of bathing areas preferably should take measures to reduce the effective eradiation dose: and (4) managers of bathing areas preferably shuuld IIlUIutur the air lailialiun Juse rate at the ueaL:h anu the like lliul cautiuJl users displaying tl-te result on a placard or some otl}er me(l~t}s ",.,hen ,Ul air radiation dose rate higher than the surrounding area is detected.

h. Use of outdoor swirrul1ing pools in schools hi Fuk'tishhl1a Prefecture On June, MEXT decided not to indicate any guidelines ror assessing the use or outdoor swimming pools because radioactive iodine, cesium and other radioactive materials had not been detected in the tap water of Fukushima Prefecture and it was thought students 113 In addition, a large a..mOlmt of rubble yvas produced by the ea..rthquake and tSlma..mi mainly \vithin the Tohoku district. Hmvever,. its disposal has not progressed either because part.s of it may be conta..T..inated \\ith radioactive rrmterial. For \vaste that is contaminated wiL.~ rudioactive rrlaterials originating from the accident at t1.e fu1..usllilna Dai-iclli NPS, t.1.e IIAct on Special rvleasures Concerning Environrnenta1 Contamination Caused by Radioacii ve lViateria1s Discharged in the Nuclear Po,ver Station Accident Caused by the Tohoku district - off the Pacific Oce:m Earthquake on March iI, 201 i" was enacted on August 26 (the provision related to waste disposal canle into efiect m January I, 20l2). ThIs Act prescribes that the Government shall dispose of waste that IS contaminated with radioactive materials originating from the accident at the Fukushima Dai-ichi NPS.

-8Rfi-OAGI0001550_00103

would only be exposed to vel}' low levels of radiation from the water in swimming pools.

When using outdoor Swiulluing pools, the levels of radiation that students \vill be exposed to should be estinmted by lTIonitoring the water in the pool (4) Measures taken to prevent the dispersai of contaminated mate"iai from the premises of the Fukushima Dai-ichi NPS

a. Scatteling inhibitor TEPCO began to deliberate on measures to inhibit the scattering of the radioactive 11laterials originatingt fro1l1 he Fukushima Dai-iehi NPS after the accident then decided to disperse an i!Lhibitor inside the Fukushima Dai-ichi NPS facilities. Then as from April I, TEPCO began dispersal testing to check the coab'Ulation status of the inhibitor and the impact on the eiectrical systems of the reactors and the spent fuel poois. As a resuit, it

\\'"as decided L.1.at orga.."'"'.J.c ai'ld inorgai*..tic

. solidirving agents 'would be used properly* in each dispersal area because the organic agents flocculates with radiation exposure in water and might block the route of the fuel cooling water. Full-scale dispersal was started on April 26 conuucLoo IIlllilually auu by using \vater waguns anu water-cannUIl LruL:ks, auu oouLrulleJ from a remote location \\*hen pig..l-t 9ir radiation dose was detected. Until JUfle 28, LlSO,OOO liters of scattering inhibitor was dispersed over 560,000 square meters of the buiidinb'S and the site of the Fukushima Dai-ichi NPS.

b. Removal of deblis at the facilities On March 12, TEPCO began (0 remove the debris scattered "ithin the premises or (he pmver staiion facilities to provide access for the vehicles used in the reoovel)' work.

Hmvever, the radiation doses of \vorkers involved in removing the debris increased because a large amount of the debris contaminated by a high concentration of radioactive materiais was produced by the hydrogen expiosion and other incidents. Therefore, TEPCO deliberated on th.e removal of debris by remote controlled heavy' equipment. TEPeO started removal by remote controlled heavy equipment on April 0 in addition to the work by manned heavy equipment that had been conducted, and completed the planned debris relTIOval \vork in Septen1ber. Fulihennore, as of August, TEPCO introduced dust collectors

-8R7-OAGI0001550_00104

in places where the air radiation dose rate did not decrease even after large debris had been rellloved to eliminate slnall debris imd dust that could not be rellloved by renlOte controlled heavy equipn1enL To prevent workers being exposed to radiation caused by the removed debris, TEPCO is storing the debris in a place far from where the workers were involved in the tasks. Tne 3

debris \\ith high radiation doses (approx. 11,000111 as of the end of September) is contained in a facili1y or vessel that is capable of shielding radiation. and debris with low radiation doses (approx. l4.000m' as of the end of September) is stored outdoors under a sheet to prevent it frmn scattering \vithin the premises oftlIe Fukushima Dai-iehi NPS.

c. Installation of ..eacto.. building cove..

After the explosion in the reactor buildings of the Fukushima Dai-ichi NPS, TEPCO plani'1ed to co\'cr L.'c reactor buildings to prevent radioactive nmtcrials frOln scattering which were originating from Units 1.3 and 4. whose outer walls and the other parts of the reactor buildings were damaged. Then TEPCO decided to start the installation work at UniL 1 bet..:ause ils [rwnt':\vurk uf Ule upper part uf the buililing was nul severely war-poo (I~fld first it '.\'(1.8 discovered tl-tat tl-te cover could be inst(llied. On June 28, tl-te fi..tll-scrue installation work began and it was completed on October 28. For Units 3 and 4, the removal of debris contaminated with radioactive materials and left on the upper part of the buildings is being conductcd as prcparatory' 'work for thc co\"cr installation,

6. OCClm-ence and treatment of contaminated wate..

(1) Detaiis of events concenling the disposai of contaminated water

a. Responses to the flooding of g):'Oundwater in the b~.sement of Llnit 6 (a) Responses to the flooding in the Metal-Clad (Me) room of linit 6 On March 19, TEPCO found flooding in the electrici1y panel room (hereinafter referred to as "I'¥1C room") on the second basement floor of Unit 6 (see Attachlnents V-3 and V-4) Stall' cleaned it up because the amount 01' flooding was so small . but the flooding continued allerwards. A switchboard installed in the MC room supplied electricity to punlps of Unii 5 RHR io cool me fuel wiihin the reactor of Unii 5 (see

• 8RR*

OAGI0001550_00105

Attachment V-5).

On lviarch 21, TEPCO found that water had accwnulated to a depth of 1.6111 fr0111 the second basenlenl floor of the radioactive \vasle treatnlenl building (RWlB) of Unjt G next to the MC room (See Attachment V-G). TEPca concluded that the Ilooding in the Me room was caused by the accumulated water in the basement 01 the Unit 6 RW/B a'-'ld notified NTSA ortheif intention to discharge the accumulated \,vater in the basement of the Unit (, RWIB into the ocean. However. TEPCa found the concentration of radioactive materials in the water in the basement of the Unit 6 RWIB exceeded the limit specified in the notification about conllnercial reactors (see the section 4 (1) c) ac-corli -il1g to the isotope ann1ysis conducted on ~ch 22 (see Table V-2). TEPCO concluded that it was difficult to discharge the accumulated water to the ocean.

TEPca then concluded from the result of a salinity measurement conducted on

~,,1arch 22 that the anlOunL of accLU11ulatcd \vaLcr in the basC111cnt of L.'c Unit (i R\VlB had increased because groundwater around the building flowed into seawater that had accumulated within the building. In ordinaty times the level of groundwater around the buililing had been ImuuLalneu al a luwer level by JisdIarging ihe \-vater in ihe suburalns inst(ll!ed [I.fou..lld each building 114 to tl-te ocean. Hm:vever, tl-te pu..rnps \,*'ithjn tl-te subdrains were made inoperable because of the station blackout and the water level rose.

TEPCa conduded that this was the cause of the flooding in the Unit 5 MC room Therefore TEPca deliberated on discharging the "vater in the subdrains (herein referred to a, "suhdrain water") in Units 5 and (, into the ocean to prevent Ilooding in the basement. However, TEPCa concluded that it was also dillicult to discharge the subdrain water into the ocean because the concentration of radioactive maieriais in the

,vater ,:vas fOlmd to be over the limit specified in the notification about commercia!

reactors according to the isotope analysis conducted on March 31.

114 The subdraiIl~ are pits that are installed in hu."gc nwnbclS aIU1Uld the buildings to decrease the level of the groundyvater thus reducing the huoyant force of the groundyvater to the hasements of buildings and preventing the grOlmd\va1er from tlmving into the basement (see Attachment V-7). TIle sulxlrains have a sbuctLu*e into which the grOlmd\va1er flows easily, and the \vater\\ithin the sulxlrains can he easily pumped out to the ocean.

-8R9-OAGI0001550_00106

Table V-2 Concentration of radioactive materials (compiled from materials supplied by TEPCO)

Conr..:el1Lraliun of nulioar.;live and other malt:rials Date Loc':ation Surfaec Iodinc 131 Ccsiulll 134 Cesiulll 137 Salinity caHeeled dose Bq/cm3 Bqlcm3 Bq/cm3 ppm

• mS"J11 Notification about 4.0x .,,-"'

I(r 6J)x .,,-"'

IU-9J)x Ilr commercial reactors Unit 6 RWIB 3/22 Not 4.9 6.0x 10*' 6.0x 10*' 6.00Oppm Oascrncnl measured Unit 5 subdrain 3/30 Not 1.6 2.Sx 10- 1 2.7x 10- 1 Not measured measured Uni16 subdr..lll1 3/30 Nol 2.0/10 4.7 4.9 lOOppm lllcHslir"J Thl; salinity or ~l\valcr isapproximatd y 30,(X)() - 3RJ)(lOrrm_ That oi"li-cshv..'aLcr is l:clmv 500ppm (b) Newly found flooding and the discharge of subdrain water into the ocean At approxinmtcly* 20:06 on April 3, a stalIlTIcmbcr on duty at the Fukusllilna Dai-ichi NPS found that water had accumulated in a trench next to the high pressure core spray system diesel generator (HPCSDG) room on the second basement floor of the Unit 6 RWlB (See ALladllIlent V-6). TEPCO cunduLieu Lhat lilis accwnulaleu waLer urlglnateu from groundyv[I.ter flooding ::a£cording to tl}e result of s[llipity measurement conducted the same day (see Table V-3).

After this flooding was found, site superintendent Yoshida requested, m the TV conference meeting ofihe Go\"emment-TEPCO integrated Response OlTice ("Integrated Response Office") held from 09:00 on April 4. a decision on what countermeasures to take in order to prevent Units 5 and (, from falling into a severe situation as that of Units 1 to 3. in those Units important equipment such as electrical systems had been submerged in \vater because grout1dv.'ater had flowed into various parts of the buildings.

Site superintendent Yoshida explained that groundwater was likely to flood the basement 1100rs of Units 5 and 6 buildings because it was impossible to drain the

• 800*

OAGI0001550_00107

subdrains in Units 5 and 6 as is described below in e (b).

in response to the rectuest, Inelnbers of NiSA, NSC 1:Uld TEPCO c1:mied out procedures [or discharging Lhe acCtLn1Ulated "vater in the centralized \vasle disposal racilities (centralized RW/B) and the subdrain water in Units 5 and (, into the ocean as mentioned below in e (b).

Table V-3 Concentration of radioactive materials (compiled from materials supplied by TEPCO)

Concentration of radioactive and other materials Date Location Surface Iodine 131 Cesiu.m 134 CeslLh"lll 137 Salinit:,

collected dose Bq/cm' Bq/cm J Bq/cm J ppm

• Trench next to Not HPCSDG room 4/3 1.6 5.SxlO 170ppm measured OfUllit6

o. Discovery ofhighiy contaminated water in the basements of Units i to 3 (a) Process of discovering highly conta..rninated water in the b~.sements of Units 1 to 3 On March 24. three stafr members of a subcontractor company ofTEPCO who were instaliing power supply cabiing on the first basement floor in the turbine building (T/B) of Unit 3 yvere exposed to radiation because they trod in the accumulated ,:vater (see 4(3) c (a) above)

When TEPCO measured the radiation levels of the accumulated water in the basements of each Unit TlB al1er the accident, it was foood thai the surface doses of the accumulated \Cvater in each Unit \vere very high: 60mSvlh in Unit 1) o-'/er 1,OOOmSvlh in Unit 2 and 400mSvih in Unit 3 (see Table V-4)

• 801*

OAGI0001550_00108

(b) Cause ofhil!;hly contaminated water in the basements of Units 1 to 3 The highly contaminated water in each TlB is considered to have originated [rom the vvatcr that rilld con1C into contact \\,iL.1. the Inclted fuel in L.1.C reactor pressure vessel or the reactor containment vessel and had flowed through some route to the TIB because at the time TEPCO had been irliecting water into each reactor pressure vessel since March 12 al Unit 1, ivl;u-ch 13 aL UniL 3 anti ivlan.:h 14 at UniL 2115 , ami in auililiuH, ihere hali

[llready been some abnonTI91ities in the re::a.ctor pressure vessels ,md/or the contra.i.n~rnent vessels of Units I to 3 before March 24 as mentioned above in Chapter IV However, the specitlc routes of leakage have not been identified because there are no details of the undergrmmd structure EU"'1d dw"'11aged area bet\veen the reactor building (HiB) a...,d the TIB.

In the meantime. until March 24 when the aforementioned exposure accident occurred, TEPCO had recognized ihe risk ihai the 'vater injected into the reactor vessels 115 Thl: clll11LLlutivc <unounLs of the \\'u\(,'[ iniected inlo Ihl: reactor pressure H.,,":'scls until March 23 arc 2.51011/ [or lJnit I, 8,2J4m~ fix 1 Jnit 2 and 4, 155nY' for 1Jnit 1 The capacitv oithe reactor containment ves~ls are 8, 140m~ fi.lr Unit I. 1O.J80m3 for Unit 2 and IO)SOm 3 for Unit J. ~ .

• 802*

OAGI0001550_00109

would be highly contaminated and then leak from the reactor containment vessels and accwnulate in the RIB. and eventually flmv out frOlll the RIB. Ho\vever. TEPeO 'VEtS not able to tm:,-e any cmm.ienneasures against the ,-vater leakage fran1 Lhe reactor vessels and exposure prevention because or other urgent problems that were or a higher priority such as cooling the reactor.

c. Deliberation on countermeasures against the highly contaminated water in the basements of Units I to 3 (a) Estabiisiunent of speciai project (earns On March 27, the Integrated Respop..se Office est!1hlished four inte!1l n1 special project teams to deliberate on countenneasures against the Fukushima Dai-ichi NPS accident.

One of these teams was the "Turbine building waste water collection &

dccontanrination tcmn" (rcnanlcd to "Radioactive accu111ulatcd \\"a1cr collection &

treatment team" as of April 1. Herein referred to as l'vvater treatment team") and ,vas established to deliberate on the treatment of highly contaminated water because the need was reoogniLtxl tu control the highly oonLCUIlinateu waler [uLUH.l in the T/Bs uf Unils 1 LU 3 after the radiation e;;.:posme accident on !\1arch 24 116 . The members of t~e te,UTl included staff from NISA, TEPCO and other organizations.

(b) Deliberation on the storage space ofhigl"Jy conta."i1inated water in tlu~ basements of Units I to 3 On March 27, the water trealment team started to deliberale on the approach to treat the contaminated water. Firstly, to prevent the highly contaminated warer in the T/Bs of Units 1 to 3 from f1o\ving into the environment, space for storing the \'vater ("storage space") needed to be secured. The water treatment team deliberated about the possible options for the storage space before deciding to use the basement of the centraiized R\V/B (the esLirrklLed capacity \\'as approximately 16,000t as of AprJ 1) for storing th.e

\vater because the racihties already existed, it had a large capacity and it \vas believed 116 Thl,'I"C \,Vl,'I"C four project te<lffi':> I,vhcn theY" \'-.'1,'I"C established on Mareh 27, but thl,'ll increased to six alK! Speci<ll Advisor to the PIime Minister, Mr. Hosono, became the general leader.

-808-OAGI0001550_00110

that the water shielding work could be conducted rather easily"'.

It "vas necessary to reillove first the sem:vater fr0111 the tsunami that had accumulated in the baselTIen! of the centralized RW/B. The ,vater tream1ent lean1 intended to discharge this accumulated seawater into the ocean and had been exanlining the possible impact on humans upon discharge and preparing inlommtion required lor the discharge.

Hov\-'ever, it was discovered that the concentration or radioactive materials in the water accumulated in the centralized RW/B was higher than the limit specitied in the notification about commercial reactors (see Table V-5), and strong opinions insisting that lithe water in the centralized RvVlB is never allowed to be directly discharged into the ocean.11 ,;vere voiced in the general meeting of the special prQlect tea.rp.s on April 1.

Therefore the plan to discharge the water into the ocean was lifted for a while.

Then on April 2, TEPCO decided to transfer the water in the centralized RW/B to the basclncnL of th.c Unit 4 TiB (expected capacity \V-as approxinmtcly 9,0001 as of AprJ 2) and started the transfer with one pump with a capacity of 25m3 per hour at 14:36. At 10:00 the next day, the number of pumps had increased to five Table V-5 Concentration of ((lruoactlve materials (compiled from materl<:lls supplied by TEPCO)

Date Conccntration of radioactivc and other matclials LC)C{-Ition Ioclliie 131 Cesium 134 Cesmm 137 collected mSvrh

~.

J:scycm

, Bg(cm; ~.

J:sgrcm Notiflcation about 6.0xW' commcrclal rcactors Baselllent of centralized 3121::: Not 4.4 RWIR 117 The fi)l1o\\ing optirms were considered as a1tematives for the f..'t01ing space: "'-'ater treatment de,-,ice tank (l9,45Ot), barge ship (3,000t), pool dug within the premises, ~uppression chambers of Units I to 4 (I O,OOOt),

suppression lXlOI \vater surge tanks of lJnits I to 4 (7,(XX)t:), suppression pool \vater surge tanks of Units 5 and ()

(J,000t), suppression IX)ol of Unit 4 (capacity" had not been calculated\ solid \va~1e storage (capacity had not been calculated) and pure \vater tank (capacity' had not heen calculated)

-804-OAGI0001550_00111

d. Outflow of highly contaminated water arOlUld the water intake of Unit 2 At approxilnately 10:00 on April 2, just before the transfer statted, a worker on duty

,\,ho ,vas 111easuring the air radiation level found that highly contmninated "vater "villI a surrace dose or over I.OOOmSv/h had accumulated in the pit located near the intake or Unit 2 that contained power supply cables. and that highly contanlinated water was iiowing out from a crack in the concrete pa.-r1~ next to the pit into the ocea..., (see V-8 to 10)118, At tlrst TEPCO thought the source of the water was the contaminated water in the pit and injected substances such as concrete"", water absorbing polymer'20 (see Attachment V-II and V-12). Hmvever, the outflmv could not be stopped. 111en TEPCO preslllned that the cause of the outflmv ,vas not the pit al1d the pm:ver supply cable conduit then1selves, but the ballast layer under them and thus began to inject water glass-based chemical solution and other materials into the ballast layer at 13:50 on April 5 (see Attaclnnent V-13 and V-14), alTer which the outflO\V \\'"as corJinncd at 05:38 on April 6 to lulVc stopped, On April 21. TEPCO released information about the contaminated water outflow accident and the estimated amount of the water that had flowed out 121, and announced l22 JIleaSW-es rela1eu tU Lhe umtrul uf uispersal auu preveuLlun uf cuni.arniuaLeu waler lU~

"lile air radiation do~ rates that \vere meHsured !.U1JLLTld the sea side of the bHrscreen (including the area neHr the pil v.,here 1he innmv or Ihe highly conlillllina1ed Willer \vas) al appmxilllaldvl6: 10 on April I \vcre L'i - 4.5111Svlh, and the rates measured in the S<Ulle ,ITea at approximately 09:30 on April 2 \'lil:rc 5.5 - 30mSvih. Th;..:rcforc TEPCO concluded that the air radiation do:e rates increased lPecause of the outt10\:v of the highly contaminated \vater. Based on this l~lcL, iL is Lhought thaL l.he inno\",* Lo the pit '-lila ouU1mv to the ~reen m-ea of the highly oonl..'lilllnated water slmtcd or rapidly in("'Tea~d during thaI p ..:rilXi.

j I'.! At 16:25 on April 2, 1.1:::1>('0 stm1ed to inject concrete into the pit ("upstream pit"), which \:vas located upstremll next to the pit that \vas lPelieved to be the somce of the outt1mv ("dmmstreml1 piC). 'lhen at 19:02, they also begrul i.llje<.:Ling CDncrete inLD the dmvnslremll pit. At that Lime, there were power supply cables between l.he dmvnstremll and upstream pit:'>, and debti:'> remained in the pit:'>. Ilowever, the concrete wa:'> injected v.'ithout removing the cable:,>

ruld debris because the concentration of the contaminated water \:vas very high.

'2!' 11:1'('0 presumed. the reason \vhy the outrlmv had not be stoppei even after concrete was iqjected. was that the coniami.llaieo \VUler l1mveo cOnilllLKJUsly through me gaps in the debris in the po\ver supply cable cDnouitlllO me pit, and LhoughllhaL lhe gaps should 11e rined in. i imvever, il \,vas dilTiculllo rill lhe gaps among lhe dehris in lhe pil because the upper part of the pit had already been sealed '.vith concrete. 'lherefore 1E1J CO decided to till. the po..:ver supply cahle condui~ mid ulus hegan to [lI.Jur high polymer \vater ahsorhing agent, Sa\Vduflt and ne\vspapers into the conduit through a hole hored into upstream side ofthe upstream pit. Tn spite ofthe11" efttl1ts, the outfln~;v could not he stopped 121 "1'1::1'('0 estimated the amounts of the radioactive materials \:vithin the contaminated water that had +/-lmved out

,vere ').41\ I n6Gnknr~ r:.f iodillP. 111 1.81\ 1o(nn(cm:< of (~esillln 114 1.81\ 1o(nn(rm-' of ('ps;nm 117 alld thf' vr:.lnmf' nf the w~ter had ~n -52Or~~3 ;~~-tot~1. 'TEPCO ~l;; ad~i~ tl~-~~ tl~e ~our~ ot'tl~e- '~~lttlO\~~~v-~s th~ c'~;ltat;l-i~ated ~~*;t~

in the l1nit 2 TIK 122 TEPCO inf.otalled, for example, steel plates in the screen of Unit 2, silt fences in the harlxn* and sandbags containing radioactive material ahsorbing agent in front of the screen rooms on Jnit<.; 1 to 4 to absorb the radioactive

-80[;-

OAGI0001550_00112

outflow (see Attachment V-IS and V-16).

in addition, on APIil 3 in the general Ineeting of the special project teams, a strong opinion insisted tha! "considering the lealmge of highly contaminated "vater of yesterday, even ir it might be required to deliberate on the discharge or low concentration contaminated water as an urgent measure in an emergency to prevent the highly concentrated water Irom l1o\ving out, it is necessary to provide a.-'1 adequate expllli"'1ation to convince the general public" was presented. This opinion led to the change of the policy of April I that had stated "never allowed to be discharged." Meanwhile, TEPCO had already stat1ed to transfer the \'vater in the centralized RvV/B to the Unit 4 TiB the same day as mentioned above in c (b).

e. Discha..ge oflow concentration contaminated wate.. into the ocean (a) \Vaterlevel in.crease in. the Unit 3 T/B (ill the pit)

As mentioned above. TEPCO continued to transfer the water in the centralized RW/B to the Unit 4 TIS from April 2 to secure storage space. On the morning of April 4, a rapiJ increase in the level uf the cunL;;unl.llaleu \valer in the Unit 3 T/B (within the pit) next to tl-te Unit 4 TlE \vas noticed (see Attachment V-I?). TEPCO conduded tl}at tl}e water transferred to the Unit 4 TIS from the centralized RW/S was also flowing into the Unit 3 T/B thiougb a path connecting in the under,,'round the Unit 4 T/B and the Unit 3 TlB. TEPCe immcdiately stoppcd thc trai'1SrCr bccausc it \\i33 belic\,'cd that it v~*'Ould cau,e an increa,e in the amount or contaminated water in the Unit 3 TIB and would now out as it had in Unil2.

(b) Preparation for discharge into the ocea..r)

Site superintendent Yoshida then explained in the meeting of the Integrated Response Office held at 09:00 on April 4 via TV conference system that the water transfer from materials as measures to control the dispersal. In addition, the storage of the highly contaminated ,vater under strict control after transtening the 'v.'ater tr:. the centrali7ed R\VIf3, separating the trench and the huilding, and the establishment of \vater treatment facilities for decontamination mld salinity, control of the contaminated \vater, among others_ \vere cited a:'> the outtlO\\' prevention measure:,> TEPCO also refen-ed to the investigation on the impact to the environment and presented some meaf.oures such 3:'> incl-easing the numher of sampling IXlints of seawater monit01ing along the coa~1 and off the com*t.

-80fi-OAGI0001550_00113

the centralized RW/B to the Unit 4 T/B had been stopped because it caused the increase in water level found in the pits of Unit 3, imd it was necessmy to decide on ml altelllatlve storage space as soon as possible. He also reported Lhat Lhe leaking of grOtmd\vUler into the buildings or Units 5 and (, was likely because the subdrain water in Units 5 and (,

couid not be discharged (see alb) above), and pointed out thal important eiectricai equipment would likely be submerged a.'1d become compromised ifno measures Vi/ere taken. He urged the Integrated Response Office to make an earliest decision on the altemative measures for these problems.

As per this request, Inenlbers ofNiSA NSC and TEPCO stat1ed the paperwork at the TEPCO henri office for the discharge of the \vater in the centralized RW/B an.d the l2 subdrain water in Units 5 and 6 into the ocean '.

Specifically, they prepared materials including a report from TEPCO (0 MET!

(NISA), an advisory dOCUIncnt frOln NSC in response to the consultation request [or advice from METI (NISA) and a report on the evaluation of the TEPCO report by NISA TIlls preparation was conducted in the same room at the TEPCO head office and Lhe pruvisiunal uucwnenls \vere uccasiunally shareu anu aIneruleu wiLhul Lhe WUIIl TEPCO ,uld NlSA e:;.:pl"jned to Prime l\1inister ¥.-'Ul, C}1ief Cabinet Secret,u;/ Ed,UlO and METI Minister Banri Kaieda (hereinafter referred to as Minister of METl Kaieda),

while preparing the documents and got their consent by 15:00 on April 2. At 15:00 the same day, the T'-,,1ETI (1\TJSA) request to TEPCa to report, the report from TEPCa to MET! (NTsAi 24 and the consultation request ror advice Irom MET! (NISA) to NSC 123 l"I ~PCO decided to discharge the \vater into the ocean as an "emergency mea:..ure" pursuant to Article 64 Clause 1 of the Act on the Regulation of Nuclem- Source Material, Nuclear Fuel Matenal mld Reactors_ It states that the "Licensee of Nuclem- Energy Related Activities, etc_" has to take emergency meaSlu-es immediately when a disasier occurs because or nuclear ruei maLerial, elC, 11' SU, lvltTlminiSler may order lhe Licensee ur Nuclear Energy Relaied Aclivilies, dc. lo lake "necessary measures" \vhen he/she rinds il ahsolulely neces..'illl)' in order io prevenl disasters resulting from nuclear fLlelmaterial. etc. according to ktiele G4 Clause 3 of the Act. 'lherefore NISA instructed TEPCO to reprir1 first its pIai] of the discharge of the ymter into the ()cean hefrirehfuid in aco.lrdance \\-lth the shpulat1cm in Article 67 Clause 1 of the Act U1 judge \vhether it should orJer the discharge he stopped.

Fl1rtheml01"e, N!S,D.. l"epOrted to NSC on the Tf--<YCO repoli in accordance '.1,'ith Article 72-3 Clau:o.e 2, and con~ulted

\O\'1th NSC ttlf its advice ttlf evaluating the TEPCO fepent The tasks mentioned in the te;.-1 ,,,ere conducted ttlf this adminif-tration 124 Tn the rep01~ Tfi:PCO e:-,1imated the impact of the discharge into the ocean on humans and concluded that effective exposure for adults in the event they ate fish and seaweed that had absorbed the discharged radioactive matelials \vould he appro:-.imately O.6mSv/year. mpco concluded it \vould not he hannf'ul to human health because this value is \vithin the same level of'the puhlic exposure limit of' ImSv/year.

,807, OAGI0001550_00114

were completed at the same time. Then at 15:20 on April 2, NSC advised MEn (NISA) and then NiSA evaluated that the discharge of the \'vater into the ocean by TEPCO \VEtS inevitable for avoiding 1110re severe hazards according 10 Lhe advice. Thus Lhe paperwork ror discharging the water into the ocean was completed.

(c) Prior notification of water discharge into the OCC~Ul After the paperwork was completed, TEPCO and the Local Nuclear Emergency Response Headquarters notified the parties concerned such as the municipalities 123 and the fishelY cooperatives associations 126 of the ,vater discharge into the ocean. On the other p!111d, since TEPCO, NISA a..l1d others started the papen:vork for the dischanJe on the morning of April 4 until they obtained the consent of Prime Minister Km1 at 15:00, they did not notily the authorities concerned (such as the Ministry of Foreign AiTairs, the

~,,1iIlistry of Ai9~culturc, Forestl)' und Fisheries, the n1Unicipalitics concerned lli'1d L.1.C fishery cooperatives associations), the IAEA or other countries of the plan to discharge the contaminated water into the ocean.

Al16:00 the same uay, TEPCO held a press L:un[ereuL:e tu <:umUWlce thal it pl:mueu to disch9~nJe some of ti}e con-rrupinated '.vater 1rlto ti}e oce<:J~'1 as soon as ti}e preparation got ready. At 18:30 the same dav, TEPCO held another press conference to announce the planned time of the discharge into the ocean127 In addition, Chief Cabinet Secretary Eduno armoui'1ccd the pllli"'1 [or the v~"a1cr discharge into the OCClli"'1 in a regular press conrerence held at 16:03 the same day. Furthennore, NTSA also announced the plan rOT the water discharge into the ocean in an unscheduled press conrerence held at 16:25 the same day, For the notification of al1d other actions regarding tl)e '.vater discharge into the ocean 125 TEPCO started at appFJximately 18:43 via fax and telephone to notify the mLmicipalities including Fukusr..bTill Prefecture, Nmnie-machi, futaba-machi, Okuma-machi, Tnminka-machi a'-'ld Nara.l-:a-machi nfthe "',vater discharge into the ocean. '['he [.ocal Nuclem- Hmergency Respon~e [leadqumiers a!~o ~tarted at approximately 15::10 via fax to notify tvfinamisoma-shi. Namie-machi, T'utaha-machi, Okuma-machi, Namha-machi, Hirrmo-machi and hvaki-shi of the "nIter discharge into the oce-tm i2(, TEPCO notified the fukushima Pretecnu'e risher-v Co-operatives Assr>eiation at 15:40 via fax and telephone.,

and the National FishelV Co-onerativesAssociation at 16:07 via te1enhone 127 TEPCO annOlIDctrl that i*t planned to strut discharging the \vater in the centralized RV;,r;n at 19:00 on Aptil 4.

and the sulxlrain \vater in 1Jnits 5 and 6 at 21 :00 the same day.

-808-OAGI0001550_00115

to other cOlUltries and international organizations, see 9 (1) below (d) Reactim! tn the dischm-ge !ntn the m~ea..'!

Minister or Agriculture, Forestry and Fisheries Kano regretted that there was no prior notiiication to the Ministry and requested MET! minister Kaieda to provide strict instructions.

Fishery cooperatives associations including the National Fishery Cooperatives Association and the Fukushima Prefecture Fishery Cooperatives Association submitted a \\Titten protest about the ,vater discharge into the ocean to TEPC0 128 , TEPCO held an expla.llatory meetLllg for the fishery cooperatives associations a..l1d the other parties concerned, and presented a comment on April 6 on the vvritten protest from the National Fishery Cooperatives Association.

For the responses of oL.1.cr C0Ui'1triCS, sec 9 (1) bclo\\'.

(e) Discharge into the ocean and ,,,lease ofthe result TEPCO si.arteu tU ilisdlafge the waLer in the centralizeu R\V/B lnlu the ucean at 19:03 on April 4. The discharge ,vas conducted using ten punlps "/ith a capacity of 25 m per 3

hour and ccrnpleted the discharge at 17:40 the sarne dav TEPCO also started to discharge the sub drain water in Units 5 and 6 at 21: 00 on April 4, and 1he discharge was completed at 1S:52 on April 0.

TEPCO analy/.ed the isotopes in the discharged contaminated water in the centrali/.ed RWIB and the subdrains or Units 5 and (, berore the discharge and in the seawater before and after the discharge. and published on April 15 129 the results in the dOcW11ent 128 The \vrltten protests \vere suhrnltted by the T'uhlshlrna PrefectLlre rlshef)'~ CO(Jr.eratlves ASSl..x;latlon on Aprl] 4; the National.FishelY Cooperatives Association, IbarrJ.j Prefecture, the heads of nine 111U1ucipalities along the coast of TI-Jaraki Prefecture aild the Tharaki Seacoa.<.;t Area fishery Cr;../perati",\;es AssriCiatirm on April h; the Tharaki Prefecture Roll Net fishery Crx1perati"ves As.:'-....'iciation on April g; and the TIxlmki Prefecture 1vfarine Product Pr0C~sing lndustry Cooperatives ,1l,s~,()Ci3.tion on ,ll,pril 1/1 1:9 TEPCO estimated that the amount of the dischm"ged Imv concentration contamiIlated \vater flDm .A.pril 4 to 10 3 3 3

,vas approximately IO,393m (approx. 9,07Om th,m the centra1inxl R'i)ilm, approx. 1,323m from the s'ubdrains in 1 Jnits 5 and 6) and the discharged arnmUlt of radioactive materials \vith the discharged \vater was app1Dximate1y 1.51\ 1011 Hq. '['he concentrations of radioactive matelials in the 1m\' concentration contaminated \vater discharged into the ocean \vere as ttlllows. TEPCO estimated the amount of the discharged radioactive mateTials based on the concentrations and the ammmt of the discharp.ed water.

-800-OAGI0001550_00116

"Result of Low Concentration Contaminated Water Discharge into the Ocean from the Fukushilna Dai-ichi NPS."

That SaIne day, NISA instructed TEPCO 10 conduct a detailed evaluation on Lhe impact on the environment of the water discharge and the other actions. Tn resonse to the instruction, TEPCO compiled the evaluation reswts orthe impact on the environment or the contaminated \\'ater discharge from the centraJi/.ed R\V/B and t.~e other facilities into the ocean, the outllow of the highly contaminated water at Unit 2 found on April 2, and the outflow of the highly contaminated water at Unit 3 found on May II based on the estimated amount of the discharged radioactive materials and the 11lonit0l1ng results.

TEPCO then submitted the outcome of the evaluation to NISA on May 20 as the "Report Conceming the Discharge of Water in which the Concentration of Radioactive Materials Exceeds the Emission Standards into the Ocean."

[, Stmi oftmnsfel' of highly contaminated watel' in Unit 2 On April 10, TEPCO completed the discharge of the water in the centralized RW/B into the ut..:e.an anu then fmisheu the walerpruu[mg wurk un the IIlaiIl prucessing buililing uf Lhe centralized RWlB on l'~pril 18. TEPCO then subfilitted a report to ::u1d notified NISA of its intention to transfer the contaminated water in Unit 2 TlB to the main processing building of the centraiized RW/B. and to control the amount of the water transferred to maintain the level up to the floor 1c\d of the first basement Jloor. The same day, 1'-.J1SA noti 11 cd TEPca that the transrer plan ;va, judged to he appropriate according to the report TEPCO then started at 10:08 on April 19 transrerring the contaminated water in the trench connected to the Unit 2 TIS to the main processing buiiding of the centralized R\V/B.

g. Measures against groundwatel' flooding in the basement of linit 6 aftel' the discharge into the sea TEPeo discharged th.e subcL.ain \\'ater in Units 5 and 6 into th.e ocelliJ during the period Water in the centrali7.ed RW/H -> Iodine 131' 6_3HC1/cm~, Cesium 134: 4.4Hq/cm'. Cesium 137: 4_4Hq/cm~

V*later in the suhdrain in Unit 5 -> Todine 131: 1,()nc;/cnr~~ Cesium 134: O.2sr3q/cnr', Cesimll 137: 0.27nq!cm:'l V-later in the suhdrain in Unit 6 -> Todine 131: 20T1q/cnr', Cesium 134: 4.7nq/~n3, Cesimll 137: 4.9nq/c~3

-400-OAGI0001550_00117

from April 4 to 9. However, the leakage into the MC room continued afterwards.

Furthennore, there \vas ne\v leakage on lvlarch 15 into other m-eftS through the ,vall of the Me roOln and the mnmm! of Lhe inilo\v ,"vater increased. Under such circumstances.

TEPCO continued to drain the water from the MC room to protect the switchboard instaiied there and then transi'erred since May i the waler in the Unit 6 TIE to a temporary ta.-.,k t.~at had been newly installed to store the contaminated \\'a1er. Allenvards, the leakage into the MC room was almost eliminated.

h. Outflow ofhig.hJy contaminated water ~u'Ol!Ild thewaterintaI..-..e of Unit 3 At 10:30 on May II, while the ;vater injection into Units I to 3 continued, TEPCO found water leaking into a pit that was located in the vicinity of the water intake of Unit 3 and contained po\vcr supply cables. According to furh1.cr investigation, the SOUi'ld of 'water leaking was detected and it was discovered in CCD image at 16:05 (see Attachment V-1 X to 20) that water was flowing out from the side of the pit into the screen area TEPCO cOIlsiueroo thaL the uullluw waLer effiuenl emIle [WIll the T/B III high concentration of radioactive lP.ateri91s siIPilar to tl-te outflm:v tl-tat had been faurld in tl-te vicinity of the water intake of Unit 2 on April 2, and then started from 17:30 the sarne day removing the cables within the power supply cable condnit connected to the pit fining

\\'"astc cloths in the po\ver supply cable conduit w"'1d ir~ecting concrete into the pit. TEPCO finished these ta,ks at 18:40 (see Attachment V-20) and conflmled at 18:45 the outllow had stopped.

On May 1L with regards to this accident of highly contaminated 'vater outflmv in the vicinity oft~e \'vater intake of Unit 3, NISA instructed TEPCO to check and report on the impact on the ocean and the route of the flow TEPCO compiled the results of the examination on aspects such as the impact on the ocean and the route of the flow, as weil as h~e pre\.'ention measures [or recurrence ill1d dispersal ill the "Report Concerrdtlg the Outnow of'Water Containing Radioactive Materials f'rom the Vicinity of'the Water Tntake

-401-OAGI0001550_00118

of Unit 3 of the Fuk-ushima Dai-ichi NPS"lJO and submitted it to NISA on May 20 m

i. Stmi Df the transfer Df hig!JJy rnnta..'l!!nated water at VIIi! 3 On April 19, TEPCO started (0 transfer the contaminated water in (he Unit 2 TIB (0 the main processing building 01 the centrali/,ed RW/B (see 1 above), On May I I, because the

\-vaterproofing works on the miscella'-'leous solid waste volume reduction treatment building (hereinafter referred to as "high temperature incinerator building") in the centralized RWIB was completed, TEPCO decided to start the transfer of the contaminated

,vater in the Unit 3 TlB, too, allhough there was still SOlne Inore space there under the high "later level compared to the Uflit 2 T/B an.d the concentration of the conta.1Jli.l1uted \vater

\vas similar to that in the Unit 2 TIB, TEPCO then carried out the prescribed procedure132 and started at 18:04 on May 17 the transfer of the water to the main processing building and the high tClnpcraLurc incinerator building of L.~c centralized R\VlB.

(2) Clean-up of highly contaminated wate,'

a. Process to simi opel"ation of the system Since the existence of the pjg..hly cont,upinated '.vater that "/[1.8 continuously produced and increased was discovered after the radiation exposure accident on March 24, how to lEFCO estimaled lhe mll0LUlts of lhe radioadi ve malelials in the contmninated \valer that had 110vved out \vere 3.4J\1013(icnl~ of iodlllc 131, 3.7J\1013q1cm:l of cesiulll 134, 3.9J\1013qicnI" of CCSIUlll 137, and the VOIUlllC of water had been 250m3 in total. ]"I ~PCO also e:-.timated that the outtlmv of the contaminated \vater statted at approximately 02:00 on May 10 by Gstablishing the correlation by IhG least squares meth(xl bct\VeL~llhe IX,TIods of an increase (U1d decreasG in the \VatLT level in thG pit of Unit 3 hefon; ,U1d aftcT Ihe ouulO\v \vas nOlieed. TEPeO al~J ccmcluded that the SOlITce of the outflmy had been the oJntaminatcci \vater in the Unit 3 TlB.

131 I\tkr this accident, 1'~1SA instmetcd TrpCO to prepare a plan for eountermea...,ure cnn:-.tmetion \vork again:-.t leakage and to conduct morIitOt"":.1l1g of scavvutcr. In re~}JOnse to the instruction, TEPeO submitted to l',IISA the "Plun for Out.flol,v Pn.,:v("1ltiol1 of \"VaL(..'[ v.iith Hig,."'1 a Ctll1e("1liratitll1 of Radioactive 1',,1aicnals at the Fukushima Dai-ichi

}WS". Fmthcr11lOfe, TEPCO notified NISA of the l--'fesc"'l:lt situmion of the accu.-rnulmcd . '.vater in L'"J.e building, the situation of the ~,turage and tre:Jhnent of the accumulated \'1:ater, and the plan for treatment of the :rig!>J)'

contm11.!naLed \VatLT by cLll..'uht!ng TI*x:lion coolTI1g that \va~ li~lL'd on the RmKh11.Hp dcscribtxi TIl (2) a Co..:lmv \""ith the "Pl!-ln ror the Storage ~l11d Treatment or V..l~l1eT \ . . ith !l High Concentration or Rmlioadive M~lkri!lls at the Fukushima Dai-ichi NPS.*'

132 TEPen Pn...11anxi a pl!ln f()T the implementati()11 ()r tIle tnmSrC'T ()r the highlv c(mt!lmina1cd \valc'T in the TJnit 2 Tffi and 1Jnit J Tffi to the main pn1Cessing huilding and the high temperature incinerator huilding of the centralized RWIH in the "RepOlt I(egardingto *I'ran~er of Water to Main I>rocessing Building and I ligh 'Iemperature Incinerator Building" and f.uhmitled it to NISi\. The same day, NISi\. concluded that the plan of transfer \va..;;; appropTiate and notified TEPCO.

-402-OAGI0001550_00119

treat the contaminated water became an significant problem for the water treatment team.

The water treatment temn ,vas deliberating on the design imd the supplier of a systenl that cleans and desalinates higbly COn1atJlIDuted ,vater (hereinaller referred to as "clean-up system") in order to reuse it as cooling water in the reactors.

Meanwhile, TEPCO prepared and announced on April 17 a "Roadmap towards Restoration from the Accident at the Fukushima Dai-ichi Nuclear Pmver Station" (hereinafter referred to as "Roadmap") stating the targets for the settlement of the accident at the Fukushima Dai-ichi NPS and the present efforts to achieve them This Roadmap summarized the settlenlent 11leasures that should be taken in each area, i.e. (1) cooling of the reactors and the related facilities, (2) control of the release of radioactive !11..aterials, a.nd (3) monitoring and decontamination, and also referred to the treatment of the contaminated water within the premises of the NPS as part of area (2). It iisted the installation of clCW"'1-up systems and the slorlllg of L.1.C decontaminated ai'ld desalinated r~ghly contaminated water in tanks as the measures to be taken within the first three months (Step 1), and the continuation and enhancement of the dean-up and desalination of the highly COnLarnillaLeu "vaLer as well as ihe reuse uf lhe pWl:t:Sseu waLer as readur oouling waLer ll (hereinafter referred to as circulating injection cooling (I.s tl-te targets ::uld the me(l.sures to II )

be taken in the neA1 three to six months (Step 2).

A dean-up system was essentiai to consistently conduct circulating injection cooling.

For this system, TEPCO decided to order the part conducting oil separation w'1d desalination from domestic companies, and the parl conducting dean-up from foreign companies that had a good reputation in the Held. TEPCO ultimately ordered the oil separation systems from Toshiba, the radioactive material dean-up systems from Kurian Be; in the USA alld Areva B4 in Frallce, and the desalination systems from Hitachi GE Nuclear 133 On :M:areh 31, L.1.e Ekdrie Po,v...:r Resean.:h Institute nx.:oml11ended to TEPCO the companies t:rillt have nx.:ords in t.~e settlement of the accident at the Three 1v1ile Island }.JPP and Kurion ""vas one of those compai'lies. TEPCO asked Kurion to submit a plDposal for ad:",orhent because the company has the technology tor high-perto!111ance

!l'-"k;orhent. Tn re~ponse to the request, Kmion hn)ught samples tf) Japan on Aplil 5. \~lhile consultations \vere taking place, TEPCO ieamecl that Kmion had the ktlc:.\v-hm'-' fCll* the system for decontamination itself. Kmicm ~'Uhmitted a proposal for a decontamination system on Apli I I 7. TIle same day, the ,vater treatment team examined the proposal and then decided to introduce the system 1~ TIXpelts n"Om 811d the then cro of Areva came to Japan on March 29 and March 30 re:'}Jectively. On March 30, the cro 811d e:-qJelts of Arev~ Special Advisor to Ptime Minister Kan and the water treatment team held a

-408-OAGI0001550_00120

Energy. On April 27, TEPCO annOlUlced 1hat it would introduce 1he clean-up systems supplied by the four cOlnpanies, and then decided to install the systems and stalled their construction on April 30.

h_ Operation ofthe dean-up systems On JUi'le 14, TEPCO started a test run or the dew'1-up systems <L"'1d then put them into full operation on June 17. The systems were forced to stop several times due to problems such as leaking of water developed during 1he test run and even after 1he full operation stmted. But, countenneasures such as repairs of the devices ,\iere taken each tillle and the systelTl..'3 have been operating ever SInce. The a.l110unt of deconta.lJlmatoo \vater 3

accumulated as of November 15 !s approximately 161,7IOm including 1he water processed by Sarry, mentioned below in d, and approximately 65. 078m3 of decontaminated 'water rillS been injected into L.1.C reactors or Units 1 to 3.

c. End of Step 1 On july 19, the GuvenlJIlent-TEPCO integrateu Respunse Offiu:) at the Nuclear Emergency Response Headqilluters checked tl-te progress of tl-te t[l.sks In Step 1, ::uld revised 1he Roadmap (revised on June 17) and published it at 1he end of Step 1 1he same dayl3'. lri 1his revised Roadmap, \\11h regards to the cooling of the reactors and reiated facilitics, TEPCO signalcd its intention to continuc und cnh&'1cc L1C circulating irJcction cooling during Step 2 and achieve the "cold shutdown,,!36. With regards to the control or the release or radioactive materials, TEPCO decided to conduct tasks in Step 2 such as enhancing the dean-up systems, increasing the reuse of decontaminaied water by consultation. On tris OCC3SH.1l1. thc water trcatmcnt team infollllcd .A. . . . ~\ra . of thc nCL--ds of TEPCO for the decontaminution ::.ystem. Then, i'\,re\'U officially subrniued a prc'lx~::.ul fm !...~e ue<...:onLm:ninuliclll system on .ALpril 7 on

[he busis of those needs. The next day, April 8, Lhe I,va!L~ [reulmL"!l! !eum e:x.:.mllillc'(i the proposal <lnd lhen decided [0

~l;~nxillee the sj"slc'1l1 IEPCO has checked the progress of the meaSLlfI":S and the o!hc~ lash listed on [he Road..TJ1J:!p, and publis..hed the revisecl Roadmap almost every'month since it preparecl and published its tirst versicm on April 17 1:1,(, Tn the report on the pmgress of the Roadmap puhlished on .Tulv 19, TrPCO defined the "cold shutdo\\ll" as the state in \vhich the temperature at the \)()ttom of the reactor pressure vessels is kept helmv I(X) degrees centigrade, and the release of radioactive matetials from the reactor containment vessels is under control and the radiation exposme dose of the puhlic due to the additional release is significantly reduced.

-404-OAGI0001550_00121

desalination, deliberating on the full-scale treatment facilities for highly contaminated "vater, and storing and administering the \vaste produced in the dean-up system..

d. New clean-lip system On August 16, TEPCO completed the instaHation 01 the new radioactive material c1eai'1-Up systems (Sarry)Ll7 assembled by Toshiba UI'1d Shaw in the USA in addition to UI'1d in conjunction with those of Areva and Kurion to consistently decontaminate the highly contaminated water. The same day, TEPCO started a test run of Sany and on AII,,'IISt 18 proceeded into full-scale operation (see Fig V-I). Since Sany went into full operation, the level of the accumulated ,:vater in the T/B of Uflits 1 to 4 dropped considerably. As of November 15 the water level has been maintained at the present target level (O.P

+3,OOOmm "o.p xx mrn" indicates the height from the work reference levei of Onaharna Port), and it is able to adapt to conditions such as heavy' fah'1.

Furthermore, TEPCO IS now deliberating on other full-si7ed clean-up systems other thanSarry.

m Sany is capable of separating oil from \vater and decontaminating the radioactive materials \vithout separating oil fmm the COlltaminated \\'aterthmugh the oil separation system (manufaculred by 'Ioshiba) l-:eforehand because it hao;;; a filter fix oil separation in the system, unlike the radioactive mate:tial decontamination ~'Y~1ems manufacuu*ed hy Kmion and Areva.

-40[;-

OAGI0001550_00122

Watcrtank (Fre:.;hwuter) i I . Vla[cr lank Desalination system

. i 1"IYIT"'o"'r,I,IrI'

';:-***r-...."*-

lllcmemtor building

[' ,

Kllrion Malll proccssmg Areva Fig V-I Outline of the flow of circulating injection cooling (after AU!,'1lst 19) (compiled from materiais supplied by TEPCO)

(3) Details of events concerning the flooding of the reactor containment vessels TEPCO decided to fill the reactor containment vessels of Units I and 3 with water to a levd abuve the fud regiun (herein referred tu as "subluelgem::e") anll. the l:in.:ulating ir~ecLiun cooling as the me(l.sures in Step 1 to consistently coo! the reactors, an.d published its iILtention in the Roadmap (April 17 edition) For Unit 2. on the other hand. TEPCO decided to seal the damaged area of the reactor containment vessel first, and then conduct the submergence and the circwating irJection as \vould be done at Units 1 w"'1d 3 ancr the damaged area \vas scaled, becau,e a major leak wa, recogni/.ed leom the reactor containment vessel and it wa, presumed to be severely damaged.

On May 5, TEPCO submitted the "Report Concerning the Measures to Fili up Reactor Containment Vessel to a Level above the Fue! Range at Unit 1 of the Fukushima Dai-ichi NPS" which presented the method and evaluation for submergence to NlSA prior to executing the submergence at Unit I. In the report. TEPCO showed that a time mar!,>in would be created by the submergence even in the event \\:a.ter injection stopped wid tlmt e'ven v..hen the amount or leaking \\"ater It-om the reactor containment ve,:,sel increased there \Vas no possibility of release into the environment. The same day. NISA notified TEPCO that the Ineasures \vere deen1ed to be necessary according to the report.

• 40fi*

OAGI0001550_00123

TEPCO increased from May 6 the amount of water injected into the reactor of Unit I and estilnated the Inagnitude of the dmnage in the reactor contmlllnent vessel by calculating the Lhe ,vater level there according to Lhe pressure change in the vessel. As a result, it concluded that there were holes in the containment vessel and the leaking would increase iCthe injection for the submergence continued. Funhemlore, it conduded that, if the amount orieaking irom the reactor containment vessel to the TiB increased, the contaminated \vater in the TiB \vQuld increase and be likely to fill up in mid-June because the highlv contaminated water in the TIB was found to have originated from the RIB. Therefore TEPCO suspended the submergence and changed their policy to cool the reactor 'Vitli the circulating il~jection cooling only. In U!1it 3, on the other ha..l1d, the submergence v*/as not being conducted, but it ,,'as presumed that the increase in the highly contaminated water in the T/B was likely to accelerate by the submergence if it were done as in Unit 1, since there had been already highly contaminated "vater in L.~c TiB w"'1d L.1.C anlOunL of \vaLer in it \vas increasing by' irJccth'1g \vaLer into L.1.C reactor. Therefore TEPCO concluded to suspend the submergence of Unit 3 and decided to cool the reactor with the circulating injection cooling only.

Accunliug tU Lhe situaliun~ TEPCO reviseu lhe RUaUIIllifJ (April 17 eiliLlun) UIl rvlay 17 ;mu stated its policy to implement t~e circulating injection cooling before tl-te submergence.

(4) Current sitnation regarding contaminated water The aInOUt'1ts and the levels or the contaminated \\"a1cr stored in the TlBs or each Unit at the Fukushima Dai-ichi NPS are as lollows: the al110unt approx 14,7501113 and the water level in TIB o.p 3,486ml11 in Unit I; approx 22,5001113 and O.P. 3,155111111 in Unit 2; approx 24.20()m" and O.P. 3,110111111 in Unit 3; and approx IX,700m" and G.P. 3,09Xllllll in Unit 4.

The total arnOut1! of the contmninated \vater stored in Units 1 to 4 is approximately 80~ 150m" (see Table V-6). After the clean-up systems came into full-operation, the water levels have dropped steadily in every Unit.

-407-OAGI0001550_00124

Table V-6 AmOlUlts and levels of contaminated water stored in Units I to 4 (as of November

15) (cOlnpiled [rOlIl lnateliills supplied by TEPCO)

Amount of fo,1orcd contaminated T,cvcl in Tm Position ofTm opLlling

\vater (CUblC meters) (O.P. nun) (O.P. nun)

Unit 1 I .~ '7c.n 1"1",1_1\..1 1O,2CXi 1Tn;t 2 22,')00 .1,lSS 4,om Umt3 24.200 3.110 4.om Ullll4 1~.7lX) 3,OY~ 4,lXX)

The GontcHYlinated ,vater 1..11 Units 1 to 4 \vas tnmsferred to the main processing bl1ildjng and high temperature incinerator building of the centralized RW/B. The amounts and levels olme waier as olme sanle day were approximately G,G5Cml' and O.P. 1,451mfl1 in me main processing building a.'1d approximately 3,270nr' a.'1d O.P 2,145 mm in the high temperature incinerator building (see Table V-7).

Table V-7 Arnount and 1evel of contarninated \vater stored in the r!lain processing building and the high temperature incinerator building (as of November 15) (compiled from materials supplied by TEPCO)

Al110LmL of stored oonlmninatl.xl Level in building Lc)Catiol1 of building "vaLc.'[ (r.:ubir.: 111(tC.T,:::) (O.P 111m) opaTIng (UP 111111)

Main processing 6,650 1,451 5.600 building

..., 1 ..1 : * ,...,/V\

3,270 ':::',l'tJ 't,':::'IJV inciner3tor building The contaminated water stored in the main processing building and the high temperature incinerator building is being deconLaminaled with the clean-up systems. Tne accumulaLed amOlu1t of the deconta.1111nated \va!er was approx. !()!,7!Om3 ; the a.1110lU1t of,vaste produced

• 408*

OAGI0001550_00125

by the clean-up was 581m3 of waste sludge and 285 spent vessels as of November 15.

(5) Ontlook on filttll"e an-angements concerning the disposal of contaminated water On November i 7, the Government-TEPCO Integrated Response OOice at the Nuclear Emergency Response Headquarters checked the progress a'-'ld other situations regarding the Roadmap and published "Progress of Roadmap towards Restoration from the Accident at the Fukushima Dai-ichi Nuclear Power Station." In this document, the Office concluded that the follmving Ineasures that had been prescribed to decrease the total amount of accul1mlated

,;vater Ll1 Step 2 \vere completed:

Decreasing the total amount of accumulated water by the consistent operation of the clean-up systems to process the accumuiated water in the buildings;

- Enhancing a.-'1d consistently' operating the clcw"'1-up systems for higl'Jji contannnatcd \vatcr and increasing the reuse of the decontaminated water by desalination;

- Starting deliberation on full-sized clean-up system for highly contaminated water;

- Slmlng ;mu IIllUtagiug the wasle sludge PWUUL:t:u by Lhe dean-up syslems [01 ihe highly conta.rpinated "~later: (I~'1d

- Installing steel pipe sheet piles in the harbor to prevent sea pollution.

Furthermore, the Office aiso concluded that the foiiowing measures that had been prescribed in Step 2 to prc\,'cnt L1C escalation or pollution in the sea by grow"'ldvI'-utcr \vcrc completed:

- Preventing the contamination or groundwater and the escalation or pollution in the sea via grOlUldwater by controlling the \vater nmv of the accumulated water into the grolUldwater; and

- Starting the installation of a cut-off wal I in front of the existing seawall of Units 1 to 4.

-409-OAGI0001550_00126

7. Estimates of the total amomIt of radioactive matetial discharged and an evalnation based onlNES (1) Tot~1 an1!mnt ofradioartive materia! discharged

a. Estimation by NISA of total amonnt disch3l'2ed NISA anaiyzed the condition or the reactor or each Unit at the Fukushima Dai-ichi NPS.

\\'ith the cooperation or the Japai'l Nuclear Energy Safety Orgui'1ization (JJ'.JES), on the basis of the data supplied by TEPCO by using MAAP (Modular Accident Analysis Program), which is a prob'fam to analyze the condition of a reactor. As a result, the total amount of radioactive Inaterials discharged fr0111 Units 1 to 3 of the Fukushima Dai-ichi NPS into !liT V*/US estil1l.ated to be 130,000 terabecquerels (TBq) of iodine 131 al1d 6,000 138 TEq of cesiU111 137. These amounts correspond to 370,000 TEq of iodine equivalent On April 12, N1SA published the result.

NISA conducted lli"'10thcr lli'1al]iSCS by also using r--"ffiLCOR (~,/lcL.1.ods for EsLinmLion of Leakages and Consequences of Releases) in addition to MAAP and using the new data provided by TEPCO. As a resul~ the total amount of the radioactive materials discharged iuLu ail was esLiIIlaLeu tu be 160,000 TBq uf iuuine 131 :mu 15,000 TBy' uf L:eslwIl 137.

These anlOurrts correspond to 770,000 TBq of iodine equivalent. On Jun.e 6, NISA published the result

b. Estimation by NSC of total amount discharged NSC estimated the integrated dose due to the radioactive materials in the vicinity orthe Fukushima Dai-ichi NPS with the cooperation or JAEA by using the monitoring results, SPEEDi (see 2 (i) above), etc. During this process NSC also estimated the amOlUlt of the materials discharged into air. As a result, the total mnount of the radioactive materials discharged into air from the Fukushima Dai-ichi NPS was estimated to be 150,000 TBq of iodine 131 and 12,000 TEq of cesium 137 (corresponding to 630,000 TEq of iodine equivalent). On April 12, NSC published th.e result.

NSC conducted 1ts analys1s aga1n later because 1t had obtained other new* inlOmlation 138 This value is dl,TIvcd from the equation of iLXline equivaknt value of cesium 137 equals lo the amolmt of cesimn U7 in becquerel multiplied hy 40 (lAl'A "User Manual 2008 l'dition" 1'.16).

-410-OAGI0001550_00127

such as environment monitoring data until March 15, which had not been obtained previously_ As a result, the total mnoill1t of radioactive materials discharged into air ,vas estimated to be 130,000 TBq of iodine 131 a..nd 11,000 TBq ofcesiun1137 (corresponding to 570,000 TBq oriodine equivalent). On August 24, NSC published the result.

(2) TNES

a. What is INES?

n~tS stands for the Intemational Nuclear and Radiological Event Scale and is an index tb.nt is fonnulated by the LA PA and the Nuclear Enerb')' Agency (NEA) of the Oftswizution for Economic Co-operation and Development to concisely indicate the significance m safety of each accident and incident at nuclear facilities.

In the practice it'l Japan, first l'-ITSA conducts a pro\"isional evaluation (provisional fr~ES evaluation) investigating the cause of an incident and after the reoccurrence preventive measures is established, the lNES Evaluation Subcommittee at the Nuclear and Industrial Safely SUUOOIIllIllLtee uf Lhe AuvisUIY CUIIllIliltee fur Nalw-al Resuwces ;mu Energy uf IVIETI exa.tpines it from a tedmic91 point of vie"l ::u1d tl-ten forml:llly eV91uates it.

An lNES evaluation is conducted by objectively jud.~~ng the level of each item of three criteria that are classified into three areas of impact ffpeopie and the enviromnent,ff "radiological ba.--ners a...,d control" at the raci1ities a...,d "dcCl.llsc-in-dcpth" 139 (see Attachment V-21). For an evaluation or Levels Ii and 7, only the criteria on the impact on "people and the environment" are specilied based on the amount or the radioactive materials discharged into the external environment. and the other criteria are not stipruated,

b. Process of making a Level 5 provisional IN ES evaluation At 16:45 on March 11. the Director of Nuclear Incident Response and Nuclear Emergenq' Public Relations Office ofNISA (berelLl referred to as th_e "director of accident 139 The clitcria on the impact on "people and the crlvironmcrlt" are based on the ammmt of radioactive matcrials discharged into edemal environment the criteria on the impact on "radiological harriers and contml" are hased on the e:\ient of the damage to ormeltdmvll offllei, and the "defense-in-depth" criteTia m-e hased on the degree to \vhich the safety of the facilities m-e seemed after an accidenVincident

-411-OAGI0001550_00128

and trouble management office") was notified by TEPCO that it had found that it was ilnpossible to inject ,vater using the elnergency core cooling systems at 16:36 that day. TIle director of accident and trouble lnanagelnent office is designated as the person responsible to make a provisional TNES evaluation or an accident that occurs at a commercial power reactor and a fast breeder reactor, etc. in Japan. He conduded that the situation had reached the state or "near accident at a nuclear power pIai'1! with no safety provisions remaining" (Level 3) of the "defense-in-depth" criteria 'M ) and notified the TAEA that the situation had been provisionally evaluated as Level 3. On March 12, the director of accident and trouble l1l8.nagelllent office concluded frmll the infonnation including the results of 1l1onit0l1ng tb.nt the situation h!1t1 reached the state corresponding to a "meltdo\vn of or da.f11.nge to the fuel resulting in the release of radioactive material of more than 0.1 % of the reactor core inventory" (Level 4) of the "radiological barriers and control" criteria14l , and noti11ed the lAEA L.~at th.c situation had been evaluated as Level 4. At L-t.mt tinlc, it \vas expected L.killt the fuel was severely damaged because a hydrogen explosion had occurred on March 12.

However, there was no objective data indicating "a release of radioactive material from the

[ud bLUlilles eyuivalent LO IIlUIt: th,m several pen::enL uf the readur L:UIt: invenlmy,,142 that is stipulated as a specific criterion for "severe darn[l.ge to reactor core" (Le"/el 5). Therefore the director did not judge the situation as Leve1S 1+J Hmvever, the director of accident and trouble management office considered events including the hydrogen explosion in the Unit 3 building on iVfarch 14, the soui'1d or &'1 explosion that had been a"umed to have occurred in the vicinity or the reactor containment vessel orUnit 2 on March IS, the rapid increase in radiation levels within the premises of the Fukushima Dai-ichi NPS on March i5 in addition to the TEPCO report on the ~.le! damage~ then concluded that the situation had reached "a release of radioactive 140 TNES "User Manual 2008 Pdition" p.J 141 INES "User Manual 2008 Edition" p.3, 32. 'lhe reactor wre invenLorv represenLs the Lolal 1.U1lount or Lhe radioactive materials within the reactor.

142 INES" User Mallua12(XJ8 .I:.'.ditioll" p.31 143 Tn the peTirxl from March 14 to 15, NTSA \vas notified by 1T",PCO that several tens percent of the fuel in 1 Jnits I to 3 had heen damaged. ((mvever, the director of accident and trouhle management office did not adopt the infonnation as the ha..;;;is for the provisional TNES evaluation on the grounds that the percentage of the damaged fuel does not indicate the relea<;e of the reactor core inventmy

-412-OAGI0001550_00129

material from the fuel bundles equivalent to or more than several percent of the reactor core inventOlY" in Units 1 to 3 and "severe damage to the reactor core" (Level 5) had occurred. He noti1ied the LAEA of his conclusion on March 18 and lnade a public announcement.

c. Process of changing to a Level 7 provisional INES evalnation On March 17, the director of accident and trouble management office asked JNES to analyze the condition of the reactors and conduct an assesslnent related to the provisional INES evaluation.

As per the request, the staff of the disaster prevention department of JNES explained the provisional results of the analysis using MAAP!44, which is a program for analyzing conditions such as L.~at of Lh.c reactor core, to the nuclear disaster prevention director w"'1d the director of accident and trouble management office. The provisional results included data that could be used to calculate the total amount of the released radioactive materials.

Huwever, these pruvisiunal resulls were suppuseu Lu have nul a sIIlall uevialluIl [runl the re[ll v(liues because tlIey had been c[llculated ,,/pjle ffi[U1Y of ti}e phmt pma.rneters of tl}e FulClShima Dai-ichi NPS were missing. Therefore the director of accident and trouble management office conduded that the provisional results could not be used as the basis for the pro\'isionru Tl"-ffiS c\'aluation.

Meanwhile, at the heginning or ApriL NSC vva, planning to puhlish the results or the estimation or the total amount or radioactive materials released based on the results or 145 SPEEDi and monitoring that NSC had conducted , The estimated vmue exceeded the 16 value corresponded to !NBS Level 7 (in the order of 10 B<I, i.e. tens of thousands of terabecquerels). Because the results accorded with the data shown in (1) b above and the 144 "1I.tfllllP 'In,,j,,,,i,, i" <In,,h]',

U~ ~ ~ ~'~.-' "." "_' _~y~'~'L~

"r ""l"I,l"l;n<r

~'L _~L~~"'ULb 11,.-, ,l,.,rr."',-'

~L_ ~-b'---

"r ,1""",,,Tt,

~'L ~"H~b-in .Iht.

~L . ._ r,,,.1

.-._. h'l'nlll""

~,,~.~~_,_.

"",1

'~L~

lh"

~L_

"Tnl\11n1 "LUV~U "r

VL (h(*

u,_

radioactj"ve materials released into tl-Je environment (outside of tl-Je huilding) by entering data :-,'Uch as (1) the shape and volume of the reactor crmtainment vessel and design data r:l the reactor cr:.re, (2) data related to r:.peratirm f,'uch a" pres~ure and temperature, (3) time of scram, ~tartup times of heat removal/cooling devices such as the isolation condenser (lCt reactor core isolation cooling (RCI C) system and high nres:'\ure core inie::tion (l11>CI) :'I'.'stem 145 Regm-din'g this publication, NSC published "int~grated r:\1e;11~1 r:\T)o~ure Le~;el (SPErDT 'tri~l calculation values ti-om March 12 to AprilS)" at the 22nd Meeting of the Nuclear Safety Commission held on Aptil 10_

-418-OAGI0001550_00130

publication of the estimated value was directly related to the provisionallNES evaluation, Special Advisor to Cabinet Office, Kenkichi Hirose (herein referred to as "Special Advisor Hirose"), \vho had conducted the aforen1entioned estirn..ation in cooperation with Lhe secretariat or NSC, provided the value estimated by NSC and proposed to the Deputy Director General of Nuciear and lnduslty Safety Agency, Koichiro NakanlUra (nerein referred to as "Deputy Director C-eneral Nakamura") a'-'ld others that l"ITSA showd publish the provisional INES evaluation based on the results of the analysis on the provided value.

As mentioned above, the director of accident and trouble management office considered that the total amount of the radioactive Inatelials released \vas derived frmn the provisional results of a MA~AP an.clysis conducted by JNES at the request ofNISA and ,vas not very precise because it had been calculated while many plant parameters had not been identified.

However, the director again asked the stall of the disaster prevention department of J}~ESl46 about the estimated value ofL.1.c Lotal Ui'110Ui'1t of the radioactive nmt. . .L~als released derived from the MAAP analysis, and it was discovered that the estimated value was in the order of several hundreds of thousands terabecquerels, the same as the calculated value

\vhich NSC hau inrncaLeu (une Oluer higher ihan the reference value uf Level 7) (see (1) above). Therefore, tl}e director considered tl}at tl}e value estimated by NISA also had certain credibility and decided to conduct and publish the provisional !NES evaluation using the estimated value.

On April 12, the Nuclear Disaster ivfw"'1agement OlTicer orNISA, Hiroyuki Fukw"'1o, w"'1d Special Advisor Hirose reported to Prime Minister Kan that the provisional INES evaluation had been round to be Level 7 according to both 01' the values estimated by NiSA and NSC on the total amOllilt of the radioactive materials released. Then the director of accident and trouble management office notified the  !.A~E.A~ that the evaluation \vas deemed to be Level 7. The same day. NISA Liaison Hidehiko Nishiyama (herein referred to as ;'NISA Liaison Nishiyama;;) and Special Advisor Hirose jointiy announced the respecti've estirrillted 'values wid tl"ULt L.1.e provisional ll-iES evaluation of Le\'el 7 had been 146 Al lhat lime. the slarr of the mS(Jsl(.,j preVL'Iltion departmL11L of JNES explained lo the director of aeeidL11L and trouhle lllffilagement oftice that the ef.,11mated value should not be used for a plm,isl0nal TNES evaluation because It wa.;; not accurate enough.

-414-OAGI0001550_00131

concluded.

The INES Evaluation Subcol1unittee of the Nuclear and industrial Safety Subconuuittee of the Advisory Committee for Natural Resources and Energy of METI is due to linalize the ol1icial evaluation aner the incident is ccmpletely resolved.

8. Details of events in areas where there may be pmblems with the pmvision of infOlmation to the pnblic (i) institutionai arl'atlgenlents for the nissen.ination of inrorrnation concenling the Fukushima nuclear accident The dissemination of infonnation about 1he Fukushima Dai-ichi nuclear accident was started first independently by (I) the Chief Cabinet Secretary, (2) WSA, which is the administration agency' for TEPeO, (3) L.1.C Local Nuclear Enlcrgcncy Response Hcadqua..-*tcrs (only after it was transferred to 1he Fukushima Prefectural Office on March 15), (4)

Fukushima Prefecture, and (5) TEPCO. HoweveJ: from March 12 1he dissemination was L:umlucLeu ;u(ler geU.ing lhe appruval uf Lhe PriIIle .wiinisLer's Offit..:e in aUvClllce illi uescribtxl belm\*" and tl}en since April 25 tl-te press release has been c::uned out lL.flder one umbrella by integrating 1he publicity of 1he Government and TEPCO as described in (([ 4 (2) b above.

From March 12 to 15, the Local Nuclear Emergency Response Headquarters did not deal vvith the press because the OIT-Bite Center, in 'whieh the Headquai*ters \vas established, \vas located within the evacuation area (Okuma-machi).

(2) Review of the changes in NiSA's remarks about reactor core conditions j1.t NIS,A., the Deputy Director Genera! ofNISA (in charge ofnuc!ear safety infrastructure) and the Deputy Director-General for Safety Examination had been mled to alternately deal with the press acccrding to the Nudear Disaster Countermeasures Manual and METTs Nuclear Operator Emergency Action Phul. On ~~farch 11. the Deputy Director-General Nakamura \vas going 10 hold the press conference At 23: 48 the sanle day, NISA was notiJied by TEPCO that a high level of radiation (1.2n1Sv/h) had been detected on the north side of the first iloor of the Unit 1 TlB. On NIarch

-411)-

OAGI0001550_00132

12, TEPCO also reported that the pressure in the reactor containment vessel of Unit 1 had exceeded the designated l11a.xlnlWll operating pressw-e since before daybreak the smne day, and Lhe level of radiation near Lhe 111mn gate of Lhe Fukusmn1a Dai-ichi NPS had increased rapidly since that morning. At the press conference at 09:45 on March 12 (the 12th report).

based on the aforementioned inionmtion. the Deputy Director-General Nakamura explalned to the press that "It 1S possible that part or the Cud cladding tubes has started to melt because this value (the water level at 09: 15 on March 12) indicates that the fuel is partly exposed".

and in response to the reporter who asked "Do you mean that the fuel could have partly stat1ed to tnelt?", he only explained that "Vile cannot deny the possibility. II Before the press briefing due at approxiw..ately 14:00 on March 12 (the 14th report),

Deputy Director-General Nakaruura notified the Director-General of NlSA, Nobuaki Terasaka (hereinafter referred to as "Director-General ofNlSA Terasaka"), lbatlbe likelihood of a core mclLdo\\,n \vas believed high because (i) L.'c values lTIcasurcd in the lTIonitoring within the site of the Fuk-ushima Dai-ichi NPS had increased. (ii) the isolation condenser (IC) was not believed to be running because a long time liad passed since the total loss of power hau UU;WH:~ll., anll. (iii) the \valer level (;unlluuuusly renminell. bdu\v Ule lup uf lhe fuel awl

'.V(I.s contlnulrlg to fall. Lfl t.l:le me:mtlme, Director-Gener(ll of NISA Terasak:a had been reported that morning that there must have been trouble with the fuel rods because cesium had been detected near the Fukushima Dai-ichi NPS. Therefore he toid Depu1y Dircctor-G~ncral for Safcty Examination Nakamura "(1fL~C fact indicates that, \vc) Clli"'lnot do nothing hut say SOli.

At the NlSA press conference at approximately 14:00 the same day (the 14th report).

Deputy Director-General Nakamura explained in more detail than the explanation at the earlier press conference at approximately 09:45 the sarne day (the 12th report), and said~

"there is a likelihood ofa core meltdown. It looks like that a core meltdmvn is occurring" After the NlSA press conference at approximateiy 14:00 on March 12 (the 14th report).

Director-G---eneral ofNISA Terasaka lea...l1oo L.~at L.~e Prime I'v1irIister's Office v~:as concerned about the NTSA announcement relating 10 the core conditions at the press conference and

-41h-OAGI0001550_00133

requested the information to the PMO prior to releasing it to the press l4'. He thus instructed the publicity still~ of NISA to get the approval of the r111ne Ivlinister's Office before holding a press conference. NISA h::1o held press conferences everyone or hvo hours Lmtil Lhen, but because of these conditions the interval between them would now be longer.

Furthennore, Director-General oj' NISA Terasaka instructed Deputy Director-General NakaJ'11ura via the other Deputy Director-General to be mindful or his remarks during press conferences because of the Prime Minister's Office's concem about NTSA's press conferences.

Deputy Director-General Nakamura took charge of the publicity until the press conference at 17:50 on March 12 (the 15th report in ,,,hich an. explan.ation for the explosion in the !VB of Unit 1 at 15:36 that day was b~ven), and then requested Director-General ofNTSA Terasaka to replace the spokesperson. Thus Director-General of NISA Terasaka instructed a rcplaccn1CIlt [or L.1.C spokesperson for Deputy Director-General [or Safety Exmr.ination Noguchi. Deputy Director-General for Safety Examination Noguchi took charge of the publicity at two subsequent press conferences.

AL the press cUIllereut..:e al21:30 un wiardr 12, a repurter ask.eu, "Abuut Ule I.;ure rndtuuwH

'.vpich is reported on TV [u1d in otl-ter media to be tlle first c(I.se ill Japan., please e;o.,:,p!(lJIl t~e meaning of it and whether the conclusion is correct or not from a perspective the public can understand.;; Deputy Director-General for Safety Examination Noguchi and other staff replied, "The condition or the core has not been dearly identified yet. "\Vc \\111 endeavor to clarifv the situation a, soon a, possible even though the outcome is uncertain" and" Although the likelihood that the core has been damaged is rather high, the details or its condition have not been established yet Tney explained ,vjthaut using the expression "core meitdmvn.!!

At the press conference at 05:30 on ]\/!arch 13 (the 1gth report), the Deputy Director-General (in charge of nuclear safety and nuclear fuel cycle) of NISA, Hisanori Nei (herein referred to as ;;Deputy Director-General Nei;'), took charge of the publicity and explahled that "The likelihood carilloL be denied because such a ITklterial (cesium) rillS already 147 F ufl h L'f 'lllvcshgahon

.. slllill be condudlxl into the Pf(X;CSS of hmv such infollnation was rcsultl.xi ,md communicated.

-417-OAGI0001550_00134

been detected and we must keep that III mind,,'48 in response to a question about the likelihood of a core Ineltdmvn at Unit 1.

At the press conference a1 17: 15 (Lhe 20th report) on March 13 and subsequent ones, NISA Liaison Omcer Nishiyama was designated as the full-lime spokesperson. Deputy Director-General Nei said at the announcement or this designation that the condition or the core had not yet been established. At the subsequent press conferences, he said that "It is certain that at least the core has been damaged ..... .It is not clear whether the core has already reached the point described by the expression 'core meltdO\\n'" explaining without using the expression" core Ineltdmvn" and only responding that the likelihood of a core lueltdm:Hl \vas unclear.

As described above, the explanation by NISA to the press changed during the period from March 12 to 13 in two respects: it refrained from using the expression "core meitdo\m" and it shilled fron1 lli"'1 affimmtivc explanation to ai'1 indication of U'-'lccrtainty about t..~c likelihood.

On April 10, NISA startecL as instructed by METI minister Kaieda coordinating the terms to be used to explain the internal condition of the reactor and analyzing the internal condition of the reactur. Since ihen~ NiSA uecideu tu ust: Ute expressiun "fud pellet IndL" insteaU uf "core meltdmvn" v/hen ~.::pbjning tl-te intem<:Jl condition of tl-te reactor, because, earlier at tl-te Integrated Response Office there had been a strong opinion insisting that "It is better to use fuel pellet melt' rather th:m 'core meltdo\\,n'.!!

On Apri1 IS, 1'-.J1SA reported the results or <1"'1 ai'lalysis w"'1d e\*a1uatlon or the internal condition of the reactors of Units I to 3 of the Fuku,hima Dai-ichi NPS at the 23rd extraordinary session of the Nuclear Safety Commission (NSC), and prepared a document about the terms explaining the condition of the reactor core. in the document, the terms 'vere defined as fo!!ov.'s: (i) !!core dmnage" is "a condition v/here a significant mnOlmt of the ~.le!

cladding tubes are damaged because of an increase of reactor core temperatures (fuel temperatures) due to a continued lack of cooling of the reactor core or an abnomral power increase in th.e core; in this situation, fuel pellets do not necessill."i.ly melt!!: (ii) "fuel pellet melt" is "a. condition in which the ruel melts because or an lnCT~1se in the reactor core 14& IA.l1Uty DircctOf-GCl.1([(l1 Nci did not usc the expression "core mdldovm" in the l(ltLT press conkn.:ncc (l[ 10:05 that day (the 19th report) either.

-418-OAGI0001550_00135

temperatures (fuel temperatures) due to a continued lack of cooling of the reactor core, which consists of fuel assenlblies, or ml abnonllal pmver increase in the core; in this situation, the fuel assenlblies and the fuel pellets Inelt and Lhe shapes of the fuel assenlblies are not maintained"; and (iii) "meltdown" is "a condition in which the fuel assemblies melt and are unable to maintain their shapes, and their melting nlils into the lower area orthe reactor core due to gravity." Based on these definitions, l'.rrSA indicated that the "fuel pellet melt" occurred in the reactors of Units I to 3.

(3) TEPCO's remar~.s about reactor core conditions On March 15, TEPCO published information about "core danaage" indicating that the percentage of the danaage in the cores was approximately 70')'0 in Unitl, approximately 30%

in Unit 3 w"'1d approximately* 25(% in Unit 3 based on L.1.C data obtained by* h1.C contaim11cnt vessel atmosphere monitoring system (CAMS/ 49 TEPCO always used the expression "core damage" when explaining the condition of the core at the press conferences afterwards.

AL ihe em! uf April, TEPCO slarleu the lVlAAP analysis (see 7(1) a abuve), which analyzes t~e condition of tlle internal slv..llltion of tl-te reactor, because tl-te data for tl-te l\~Aj'J> <:J~t}<:Jlysis became available. At the press briefing on May 12, TEPCO explained the condition of Unit 1 as "the fuel assemblies melted and feil into the lower area where they are cooled" based on the provisional result orihe 1\1AAP lli"'1a1ysis.

FurthemlOre, TEPCO puhlished the alorementioned provisional evaluation in the "Condition oUhe Reactor Core ofTEPCO's Fukushima Dai-ichi NPS Unit I" on May 15, in which it said that "it has been concluded that the fuel pellets in Unit 1 melted and fell into the bottom of the reactor pressure vessel relatively soon after the tsunarni had arri-'/ed. This II description corresponded to the "meltdown" as defined by NISA.

TEPCO obtained and checked all the data required for the analysis on May 16 and then published th.e final results ofL.~e llilalysis on ~v1ay 24.

149 Thl: l:ontainmL~ll vl:ssd almo~'Ph.;,;rc; monitoring system (CAlv1S) monitors Ihl: radialion kvd \vithin till: n.:ador containment vessel after a loss of coolant accident and the measured values are used as important inputs ti.lr estimating the percentage of core damage.

-419-OAGI0001550_00136

(4) TEPCO's public reiations activities and the invoive:ment of tile japanese govennnent Fron1 March 11 to 15 the Fukushinm Prefectural Elnergency Response Headquarters held its meetings several times a day at the Fukushima Prefecture Ii chi Kaikan ("Local Govemment Halr). Tne Headquarters made the staiT 01 the TEPCO Fukushima OOice who

\'vere dispatched to the Headqtilli'"ters right aller the earthquake report infonllation about the Fukushima Dai-ichi NPS at its meetings. The meetings were open to the press.

In the evening of March 12, the chief of the TEPCO Fukushima Office was requested by the Prefectural Enlergency Response Headquat1ers to explain at the 11leeting of the Headqua..rters the explosion in the RIB of Unit 1 that had occurred at 15:36 that day.

The chief had been requested by the press agencies and others to supply photo!,'faphs of the RiB of Unit I after the explosion. Therefore he decided to use the photograph of the RiB of Unit 1 after L.1.e explosion that had been shared within TEPeO for the explai'lation and showed the photograph in the meeting of the Headquarters' members that night at his own discretion.

Huwever, UIl .wian.:h 13, Lhe Prune .wiinisler's Office \varneu ihe TEPCO presiuenl,

!\1asataka SbiIPizu, ag(linst publishing the photograph \vithout first notifying the Prime Minister's Office. President Shimizu therefore instructed the manager of the Plant Siting and Re!,>ional Relations Deparhnent of TEPCO to get the consent of the Prime Minister's Offiee on items such as texts a.-'ld materials to be published prior to releasing them to the press. Since then TEPCO got the prior consent of the Prime Minister's Ollice on items such as texts and materials to be published.

(5) Dissemination of information about tl}e Unit 3 reactor conditions In the press conference at approximately 15:30 on March 13, Chief Cabinet Secretary Edano explained that there arose a chance of a hydrogen explosion in the RiB of Unit 3 similar to the one at Unit 1 in I'v1arch 12 because the irJection of "vater temporlli---ily' became unstable and the w-ater levelln the r~1ctor decreased during the Freshw-ater and sea,\vater injection into the reactor of Unit 3 that led to the reactor core being insulliciently cooled, and consequently it could not be denied that a large an10oo1 of hydrogen ,vas produced

-420-OAGI0001550_00137

within the reactor of Unit 3 and had accumulated in the upper area of the RIB.

in the press conference at m-Quad 11:00 on Ivlarch 14, Chief Cabinet Secretary Edano

\-\-'as explaining Lhe follo\ving. TEPCO instructed at 06:50 Lhe outdoor \vorkers to temporarily evacuate because the pressure in the reactor containment vessel of Unit 3 had increased. However, the outdoor work was resumed because the pressure in the reactor containment vessel decreased aner that incident. Hmvever, the R/B of Unit 3 exploded during this press conference. Chief Cabinet Secretary Edano told the press that an explosion might have occurred because white smoke was being emitted from Unit 3 at 11:05 on lyfarch 14, and the situation was under investigation.

Prior to the incident mentioned above, Fukushirra2 Dai-ichi NPS site superintendent Yoshida notified TEPCO head office at approximately 06:00 on March 14 of a rapid increase in the pressure in the dry well of Unit 3. Then at 07:53 on March 14, site superintendent Yoshida notillcd TEPeo head office that L.~c pressure in the cL.~~.'\vcll had been 460kPa abs and exceeded the design maximum operating pressure of 427kPa abs as of 6:10 the same day, and determined that the situation corresponded to an "abnormal increase in cUIlLaiIllIleut vessel plessw-e" (sLipulateu in Clause 21 Sediun 1 uf Um enforcement regulations of tlle l'~ct on Speci[lllVleasures Concerning Nuclear Emergency Preparedness, "Large Reactor Facilities" (iii)). In response to the notification, TEPCO liaison officer to the goverument A at the head office instructed the staff B, who had been dispatched to the Prime ivrinister's Office then, to get the consent or the Prime ivrinister's Office and NTSA on the publication of the incidenL the ahnonnal increase in the pressure of the containment vessel of Unit 3. Staff B explained to the NTSA officials who were stationed on the 5th floor of the Prime Minister's Office about the abnormal increase in the pressure of the containment vessel of Unit 3 by indicating the draft text for release to the press that had been prepared by the TEPCO publication team. The NISA officials instructed TEPCO staff B to wait for a while because they had to coordinate with the Prime rv1inisters Office. Finall~y th.e NISA officials instructed TEPCO staJIB th.at TEPCO should nol release Ihe incidenl 10 the press ahead of lhe government As a result, TEPCO did not release details to the press after all about the abnomlal increase in pressure of the contaiml1ent vessel or Unit 3.

-421-OAGI0001550_00138

On the other hand, the staff of the TEPCO Fukushima office mainly reported the condition of the plant at the Ineetings of the Prefectural Elnergency Response Headquat1ers and Lhe Ineetings "vere opened to Lhe press as described in (4) above.

Tn the early morning oJ'March 14, inlannation on the pressure increase in the reactor containment vessel oiUnit 3 was delivered to the TEPCO Fukushima office. Tne chiei oithe TEPca Fukushima olTice requested TEPeo head oOke ror their consent to explain the abnormal increase in pressure of the containment vessel of Unit 3, in the meetings of the Prefectural Emergency Response Headquarters. However, the manager of the Plant Siting and Regional Relations Depat1nlent of TEPCO instructed the chief of the TEPCO Fukuspj!11.R office to refrain from publisping the infonnation because he hnri been instructed by NISA to wait for press release on the matter.. Therefore the staff of the TEPCO Fukushima olIice could not explain the abnormal increase in pressure in Unit 3 in Lh.c ll1CCtlng of th.c Prefectural En1crgcncy' Response Hcadqua..-tcrs held at approxinmtcly 09:00 on March 14.

Later at 09: 15 the sarne day, NISA liaison Nishiyama explained in the NISA press L:un[erem..:e that the press me in the reaclm cunLalluIleul vessel uf Uuil 3 exrueueu Um uesign maximurn operatl....'1g pressure.

(6) Al1Ilouncement conceming the detection of teUnrium, etc.

a. Publication of the results of the isotope a.,alysis by r-.,TISA As descrihed earlier in 1(1) h, the Local Nuclear Emergency Response Headquarters

("Local NERHQ") conducted radiation monitoring around the Fukushima NPS during the period from March 11 to 15. As a result, radioactive materials such as iodine 131 and 132, cesium 137 and tellurium 132 \X/ere detected \X/ithin: (1) atmospheric suspended dust collected in Narnie-machi during the period from 08:39 to 08:49 on March 12, and (2) atmospheric suspended dust coilected in Minamisoma-shi during the period from 13:20 to 13:25 the Sful1e day.

How*ever, the secretariat of' the Nuclear Emergency Response Headquarters did not publish immediately most of the results of the monitoring conducted during the period

-422-OAGI0001550_00139

from March 11 to IS, and disclosed most of it for the first time"~ on June 3.

When publishing the "Results 01' the Emergency Monitoring in the Vicinity 01' the Fukushima Dai-ichi and Dai-ni NPS (conducted ieom March lito 15)" on June 3, the Loca1 Nuclear Emergency Response Headquui'ters explained the process ui'ltil the publication as in the following: "the Local Nuclear Emergency Response Headquarters evacuated from the Off-site Center in Okuma-machi on March 15 151. As it was necessary to check the data left at the Off-site Center. the staff of the Off-site Center visited the building of the Center in OkUlYl.a-111llChi again to retrieve the related files an.d integrated the results of the monitoring on May 28. Now;ve can publish the results today on June 3."

However, the results of the monitoring conducted in the vicinity of the Fukushima 1'<1'S in the period [ronl ~lI1arch 11 to 15 had been Lra...'1smittcd fro111 L.~c Local Hcadqulli."1crs to L.1.C secretariat of the Nuclear Emergency Response Headquarters. The staff of the secretariat of the Nuclear Emergency Response Headquarters who received the transmitted results published unly the resul~ uf the IIlUJutmiug thal hOO been integrat.eu in the [oHn uf tables by the Loc(ll Headquarters, an.d did not integrate by himself ti}e other results into t..l:le form of tables or any other form and left them as was without publishing. Early in May, the secretariat of the Nuciear Emergency Response Headquarters started to integrate the monitoring data that had not been published a."'1d prepared them Cor publication as \vell as arranging the unpuhlished results 01' independent calcula1ions using SPEEDT 152 Cor publication. The secretariat instructed the Local Headquarters to arrange the unpublished monitoring data for pubiication. According to the instruction, the Local Headquarters integrated the monitoring data and retrieved the materials left in t~e Off-site Center in 150 NlSA published part of the moniloring: resulls immediately. For eXffillple. 5.8Bqlcubic meter of iodine 131 I.md 1.7T1q1cuhie meter of tc1lmium had hccn detected in atmosphcTie fo,Ufo,p...lldcd dust collected in finnt of thc Environmental Radioacti"ity Monitming Center of T'uKushima during the T"leIiod tinlll 08:00 to 08: lOon Mm"dl 1\

and NTSA puhlished this infi.)Tmation at the same time v.'hen the earthquake damage infi.)Tmation (the 22nd repOTt, a..;;

of07:30onMaJ~h 14).

,; See TTl 5 (3) alxwe.

152 Thl: :n.:sulls of the indqx,'rKl(.,11L c(Jleulalion by NISA using SPEEDI VV("'IC published gradually on May 3, JLlll: 3, II, 28 and July 24.

-428-OAGI0001550_00140

Olmma-machi. At that time the aforementioned unpublished data were retrieved and integrated, and then published on jlU1e 3.

(7) Ambiguity conceming the negation of "immediate" effects on health Tue Government oilen explained, "It does not have immediate eilects on humans" about the inl1uence oCradiation on the hUmai'1 body_ For example, in the ChierCabinet Secretary's press conference at approximately 18:00 on March I G. the Government explained that "It is not an amount that \\111 have immediate effects on the human body" about the monitoring results on the same day (the values over 30~Sv/11 had been obtained in IiLate, lvfinall1isOllla nn.d Narpie); the Govem.111ent also explai.l1ed in the Chief Cabinet Secreta.TY's press conference at approximately 16:00 on March 19 that "Please understand that the amount of exposure does not have immediate eiIects on the health of citizens (even if you briefly ingest food [rOlTI \V1:11Ch radioactive nmt....L~als exceeding the provisional limit is detected), so please act calmly" conceming the detection of radioactive materials exceeding the provisional limit prescribed in the Food Sanitation Act from the milk extracted within Ful...ushima Prefecture awl Lhe spinach hmvesloo within lbaraki rrt:[ecLw-e. ill aJililiun~ the CUHswner Mairs i\~gency exp19ined on t..l:le Agency's \veb on !\1arch 20 t..l:lat lilt is not believed to have an immediate effect on your health even if you occasionally ingest food in which radioactive materials exceeding the provisional iimit prescribed in the Food Sanitation Act were detected " in the message IIAbout Delivery Restriction on Food Because or Detection or Radioactivity" Irom the Minister of Consumer AlTairs, Mr. Renho. Similar explanations were repeated in the later messages of March 21 and 23. Furthen11Ore. NSC also explained to the public that "Even if you continue to ingest food in vvhich radioactive materials exceeding the prescribed limit are detected~ it ,vi!! not have immediate effects on your health in the notice II "To the People Living Outside the Areas where Evacuation or Sheltering Indoors is Conducted;; on March 21, 2011.

It seems that th.e expression "immediate" effects vvas used on the basis of the follovving scientiflc knovdedge: the causalities between radiation exposure and the occurrence or diseases such as cancer is not clear for low-level radiation exposure; and it will take a considerably long tin1e for cancer to occur if it ever does (see 4 (1) b above). In fact, the

• 424*

OAGI0001550_00141

expression "It does not have immediate effects on fue human healfu" may be interpreted by sonle people as "it is unnecessary to be atL"'\.iOUS about the inlpact on the hWllan health," '\ihile it nm:v be interpreted by other people as "It does not imn1edia1ely alIect hwnan healLh, however, some eOects will be brought about on the human health in the longer teml."

However, it was not necessarily dear which one the intended meaning was oi'the expression a'-'ld there \,vas no detailed explw'1a1ion about it The Consumer Affairs Agency deleted the word "immediatelv" from the aforementioned message on April I. Wifu regards to fue intention to have used fue expression "It caonot be considered to inuuediately affect.." in the "Q&A for Food and Radioactivity" page on the Agency's ,vebsite" the Agency explained that acute symptol11.5 "/QuId not develop in the human body even if food in which radioactive materials exceeding the provisiona1limit were detected were occasionally ingested because the radiation level from the ingested food is very lo\v, but L.killt L.~c inl1ucncc in case vI-hen the ingested radioacti\'c materials accu111ulatc in L.1.C human body cannot be completely denied because they are radioactive.

9. Deiaiis of events in aI"eaS where then.~ may be pn)oiems concerning the provision of information to tl!e international cmnmunity (1) Provision ofinfOlmation concerning the discharge of contaminated water into the sea

a. Notit1cation of the discharge of contaminated water into the sea to other countties and international organizations As descrihed ahove in (, (I) e, TEPCO decided to discharge relatively less contaminated accwnulated waler into the sea with the consent oCNTSA on April 4. However, no stall' at NiSA vvno had been invoived in the paperwork for the procedure required for the discharge recognized or pointed out the necessity of noti~/ing related foreign countries.

After it was decided fuat the discharge would be conducted, a staff member of NISA who was watching the Chief Cabinet Secretm,is press conference that started at 16:03 on April 4 lli"1d recogrIized tIle need [or notification, then visited the ERe to obtain the Inaterials related to the discharge into the sea, and then noti lied the TAEA 01' the discharge via email at17:4G the same day.

in addiiioll, alter 15:30 011 April 4, a simi ll1enlber of me Ivlinistry of ForeIgn AiIairs,

-42[;-

OAGI0001550_00142

who was at the Integrated Emergency Response Office, learned that TEPCO was planning to dischm-ge the contaminated \'vater into the sea and notified the related divisions \'vithin the Ministry about it. The ne,,,'s \-vas COll1l11unicaied via enwl fron1 a lTIobile phone to the stalT member oUhe Ministry who was in charge of publication during the regular briefing that started al i 6:00 the same day, Tne staiT member notiiied the diplomats of the foreign countries of the news in the briefing. The discharge of the less contaminated water \\ithin the centralized waste disposal facilities actually started at 19:03 the same dav, The Ministry of Foreign Affairs was notified of the planned discharge into the sea by the Ministry staff 11lelnber \vho had been stationed at the Integrated EUlergency Response Office, then infonned all the diplomatic corps via ew.nil a.lld fax that the discharge ,:vould begin tb.nt day.

However, the notification stating that the discharge ,vould beb~n that day was sent at 19:05 the same day after the discharge had already started at that time, On April 5, L.1.C ~lI1inistry of Foreign AlIairs and NISA agaL."'} explained the details of th.c discharge of the contaminated water into the sea and its impact in the regular briefing that started at 16:00 (47 countries and two international organizations attended). Furthermore, UIl April 6, the iviinisLlY uf Fureign Mairs explained the uetails uf the ilisdmrge emu its impact to t..l:le embassies of South. Korea, Cp.lrlH ,u1d Russia located in Tokyo.

b, Question fmm the view point of the fulfillment of international commitment As mentioned earlier in (; (1) c (b), NTSA conduded that the discharge or the less contaminated waler into the sea conducted on April 4 did not have a significant impact on human health because the total elTective dose had been evaluated to be 0.6mSv/vear which "vas below the 1mSv/year vmue stipulated as the dose limit in the rules and notification about commercia! reactors (see 4 (1) c above). The next day) on Apri! 5, N!S,A~enquired the Ministry of Foreign Affairs whether the discharge into the sea complied with the treaty, and received a response that said the discharge did not fall within the scope which requires notification prescribed in AL,..jtic1e 2 of L.~e Con\'ention on Early Notification of a Nuclear Accident 153 153 Thl: lvfinisll\.' of Foreign Mairs (Jiso responded 10 the Investigation Conul1iuo..: thaL "the (hschargc dt)Cs nol cOlTespond to an event fl1ipulated in Article 1 of the Convention on Early Notification of a Nuclear Accident (from

-42fi-OAGI0001550_00143

With regards to the obligation to notifY prescribed in Article 19~ of the United Nations Convention on the La\'v of the Sea., the IvlinistlY of Foreign Affairs said, lithe dischm-ge does no! correspond to the event lin \\-hich the lTI::lrine environrnen! is in imminent danger or being damaged or has been damaged by pollution' prescribed in Article 198 or the United Nations Convention on the Law of the Sea" and concluded that the discharge does not Cal] \vithin the scope ;-vhich requires Japa.."'1 to noW)' other CQuJ'ltnes as stipulated in the Article""' However. the Ministry of Foreign Affairs does not believe that there is no need for notification. Foreign Minister, Takeaki Matsumoto, said to the Committee of Foreign Affairs of the House of Representatives on April 13, IIvVe should sincerely consider the problem presentation (from foreign COlll1tries) that requests detailed explanation in advance and also ;yill make an effort to resolve the problem". Even if no notification obligation is stipuiated in treaties, it is logicai to consider that it is necessary to noti1y the related COUi'lU1CS aroui'ld Japan of the discharge in advance.

Furthermore, there are remarks that say it is not acceptable to discharge without any notification or consultation and Japan should get the agreement of neighboring cOlUltries UIl the ilisdlarge even if the L:unL:enlraliun is rather lu\v.

(2) Supply ofiufonnatiou to other countJies iu the initial petiod after the accident

a. Framework ofiufOlmatiou provisiou to other countJies The Government held regular briefings regarding the Fukushima 1".JTlS accident in principle once a day during the period Irom March 13 to May 18 and three times a week arter May 19 lor the diplomatic corps residing in Tokyo. Tn the brielings, the explanation about the status and oolUltermeasures regarding the accident was given by the staff who

\vere in charge of the respective area and \vere mainly from the Foreign  !\1inistry~ but also from NSC MEXT, the Ministrv of Health_ Labour and Welfare, the Ministry of

\vh1ch a release of radioactive material (xxurs or is likely to occur and \vh1ch has resulted or may re::,ult in an intemational tran:,,:houndary release that could have radiological :",afety significance for another State') and it does not fall \vithin the scope yvhich requires notiticaticm as ~tipulated in .A.!tide 2 of the COllventicm.

1.~4 This "\vas pre-ented as a re<..p_1nse to the inquil;' of the Investigation Committee_ Pmthennore, the discharge is also not considered to he a hreach nf dut\' (tn take appropTiate steps in the event that a release of radioactive materials into the environment occurS) as stipulated in Article 24 Sectinn 3 nfthe Jnint Cnnvention on the Safety of Spent ruel Management and nn the Safety of Radinactive V,laf.o1e Management hecau.<.>e it wa.;; conducted a<.; a legislative measure also nn the hasis nf npininns of the regulating agencies.

-427-OAGI0001550_00144

Agriculture, Forestry and Fisheries, the Fishery Agency and NISA

h. Infmm.atinn PrDvision tn t.i!e USA after t.1!e a~ddent m~~l!n-oo The United States was greatly concemed about the status or the plant at the Fukushima NPS lrom the moment the accident had occurred. Ahhough experts lrom the United Stales Nuclear Regulatory Commission (lJS}ffi.C) <L"'1d DOE contacted the agencies concerned to gather information, the United States could not get suiticient information. However.

re,,'lIlar consultation between Japan and the US was initiated by the Prime Minister's Office on lviarch 22, then the information and vle\vs regarding the plant ,vere exchanged and the acceptal1ce of relief supplies ,,'as coordinated during subsequent cOP..5ultatiop..5. The consultation between Japan and the US significantly improved the flo,v of information regarding the plant for the US.

10, Coo ..dination with othe .. countries and the IAEA (1) COOl'dination with othe .. countries and the IAEA As ueslaibeu abuve in 9 (2) b, the regular L:oIlsullatiuIls inilialeu by the PIlUle tviiulsLt:I's Office on IVlarch 22 bev.veen Jap,ul <:J~t}d tl}e US v/ere attended by tl}e DOE 3fLd t~e NRC of the US, the agencies concerned in Japan and TEPCO who shared and exchanged information and views regarding the plant and coordinated the acceptance of relief supplies.

DUling thc consultations, thcrc \\'"crc n1lli'1Y olTcrs or cooperation such as the provision or barges that contained ireshwater l55 , stationing or llS experts at the Integrated Emergency Response Ollice, integration or the results or monitoring analysis by tbe DOE and the SPEEDi anruysis in japan. and consultation about the use of remote controlled robots for momtonng al1U-- remm'mg

........ ,es,I~'ae h' ru hhl . . f!S 156157 155 l\ bartSc containing fn.:shv..'atL'r ,vas o1IL'nxi by thc US in thc consultation [X,.:t'*VCL11 Japan and thc US onl'. .1ar...:h 23 llt"'1d rvvo harges supplied \vater to the fukushima Dai-ichi l'JPS on April!.

i.'X, On March !5_ before the consultations het<,veen Japan and the lJS began, t<.vo fire engines '.vere offered by the 1Jnited States /\nned forces in JUpa.l1 and used for the spr~ving of \vater em the ~pent P.le1 pool of 1Jnit 4 on "rv1"arch 157 Dtl1ing the consultations bet\veen Japan and the US on March 25. three pmiect teams \vere e~tahlished to delil:terate on issues in the respective fields: (\) the shielding Pl (yvhich delil:terates on shielding methods to prevent the radioactive mateTials from being relea..;;;ed), (2) the fuel rod retJieving and transfer PT (\vhich deliberates on methrx:ls to retJieve the spent fuel ti'om the power ~iation), and 0) the remote contJul PT (\vhich deliberates on

,428, OAGI0001550_00145

(2) Supp0l1 fnnn otiler coulluies and japan~s response to their suppm1 Wilh regards 10 the oITers of support fronl foreign cOLmlnes regarding to lhe Tohoku District the Pacilic Ocean Earthquake, the Ministry or Foreign Affairs mainly coordinated the recipient orit since the day the disaster had occurred.

\Vith regards to the Fukushima 1"WS accident, various equipment \vas oITered by foreign countries such as water pumps to use for the cooling of reactors. tire engines. barges containing freshwater, remote controlled robots, gamma cameras, protective clothing, protective nlaSks_ nlOnitoring vehicles, aerial nlOlutoring equiplnent, genna1llUln se!1liconductor detectors and personal dosimeters.

Furthermore, protective clothing, rubber gloves and boots came soon after the rriddle of March, and severai countries supplied those materiais at the request ofJapan.

On L.~c othcr ha."'1d, L.~c GovCITlnlcnL dcclincd oilers of cquipnlcnt that requircd traL'1ing on their operation before acceptance or equipment that was plentiful in Japan. For example, the offer to supply stable iodine was declined because there were large stocks of it in Japan and Lhe stmage miu lrmClpuItatiuu u[the stable iuwue oITereu Willi expeIClive because il Willi in the form of liquid_ Fu..rtJler, t~e offer of remote controlled umnam1ed robots ,vas declined because it was necessary to be trained in their operation in the country supplying the robots. In addition, one country offered to supply monitoring vehicles, however the acceptance was delayed becausc it took a long timc to orgunize drivers \vho could operate them l58 .

The equipment olTered by the US wa, readily accepted becau,e it wa, coordinated during the consultations between Japan and the US in which the agencies concemed attended.

Fwthermore, since early April, the use of a "US-japan Nudear-Reiaied Assistance Tracker"

\vas propose~ \vhich Vias an integrated at-a-g!ance fonnat that represents information such as an explanation about the equipment that could be supplied, the destination of the equipment and the party who wouid accept them. This system iead to the acceptance of the rehef methoos for uTImmmed vvork in areas of high rmlialion).

158 The cmmtrv made the Ofl:L~- on thc c~nditioll that cOlmtrv ~llpply a chivcr, too, bccau'3C tramillg is required to dlive the monitoring vehicle ))mvever, hecau~e of difficultie~ in communication, the Ci-ovemment requested that that countly' tl-ain Japanese ~taff to operate the meaf.ourement equipment at the emba~~y of that cmmtry and supply only the monitminp. vehicle

• 429*

OAGI0001550_00146

supplies being more coordinated.

On March I G, the US recommended US citi/ens residing in Japan evacuate I[om the area within a 50-mile (80km) radius or the Fukushima Dai-ichi Nl'S. Tne recommended e\'acua11on distai'lCe or 50 miles was specified by the NRC on the basis of the \vorst-case scenario estimate of radiation levels. Tn addition, that same day, the US recommended the families of US government staff evacuate voluntarily from Japan.

On April 15, the US \vithdre\v their evacuation advice on Ivlarch 16 for the families of US goverrnnent stnff. Furthennore, on October 7, the evacuation area v.,ras decreased to a 20lclll 159 radius from the 50-mile radius that had been specified on March 16 Some countries other than the US also published evacuation advice similar to that of the TTQ V~.

(4) COOl'dination with the TAEA ArLide 2 Sel:LiUIl 4 uf Ute Cunventiun un Asslst,mce in the C~e uf a Nudear Al:L:iuent OJ Raruologic(ll Emergency stipulates tl-tat sig.1latory countries sh(lll noti~/ LAEA of e:'<:.perts, equipment and materials that could be made available to other signatories to assist them in the event of a nuciear accident or radiological emergency within the bmits of their capabilities, On TVfarch Hi, Japai'1 asked the TAEA to provide infommtion regarding items in the possession or other signatories such as remote controlled monitoring robots, aerial survey systems, unmanned trucks and unmanned helicopters. Tn response to this request, TAEA asked several countries to provide infommtion about their respective equipment. Tne countries responded after March 17 al1d Japan accepted the equipment that those countries could supply such as the remote controlled robots.

159 ))mvever_ the lJS govemment recommended LIS nationals avoid enteling the deliherate evacuation area and the specific m-eas from \vhere evacuation wa.;; recommended hy the Japanese govennnent even those beyond the 20km radiu_,,>

-480-OAGI0001550_00147