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NRC-2019-000389 - Resp 1 - Final. Agency Records Subject to the Request Are Enclosed
	ML19224C325
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Issue date:	08/08/2019
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	FOIA, NRC-2019-000389
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Harmon, Curran, Spielberg+ Eisenberg LLP' 1726 M Street NW, Suite 600 202 .328.3500 I office Washington DC 20036-4523

202.328.6918 I fax (BXOO)© HarmonCurran.com March 22, 201 l FO IA Officer DIie Rec'd:

epecialiat Office of Information Resources U.S. Department of Energy Mailstop MA-90, Room 10-051 10000 Independence Avenue S. W.

Washington, D.C. 20585

By e-mail to: FOIA-CENTRAL<@,hq.doe.gov FOfA Officer National Nuclear Security Administration Attn: OPA P.O. Box 5400 Albuquerque. NM 87185-5400 By e-mail to: FOTOfficer@.doeal.gov NRC FOIA/PA Officer U.S. Nuclear Regulatory Coinmission Mailstop T-5 F09 Washington, DC 20555-0001 By e-mail to: FOIA.resources@nrc.gov Re: Freedom oflnformation Act Request

Dear FOlA Officers:

On behalf of Friends of the* Earth!(FOE"),. the Nuclear Information and Resource

. Service ("NIRS), and Physicians for Social Responsibility ("PSR") (hereinafter "the Req\lesters"), and pursuant to U.S. Department of Energy ("DOE") and U.S. Nuclear Regulatory Commission ("NRC") regulations for implementation of the Freedom of Information Act ("FOIA"), 5 U.S.C. § 552, I respectfully request copies of the following records:

( 1) All records created since March I 0, 2011, containing measurements of radiation released to air; soil and water from the Fukushima reactors in Japan; (2) All records containing analyses of measurements ofradiation referred to in paragraph ( I ) above; and (3) All records relating to the crite1ia and/or protocols used for the conduct of the radiation measurements and/or analyses described in paragraphs (1) and (2) above.

j Harmon,* Curran. Spielberg + Eisenbe*rg LLP

@sXOO)

FOIA Officers March 22, 2011

Page2 This request covers all records in the possession of the NRC and/or DOE, including but not limited to data collected by your agencies and/or other federal agencies and/or foreign governments. This request also includes any data or analyses collected and/or created by the DOE's National Nuclear Security Administration ("NNSA") under its Aerial Measurement System*.

For purposes of this request, the term "record" means: (1) any written, printed, or typed material of any kind, including without limitation all correspondence, memoranda, notes, niessages, letters, cards, telegrams, teletypes, facsimiles,

papers, forms, records, telephone messages, diaries, schedules, calendars, chronological data, minutes, books, .

reports~ charts, lists, ledgers, invoices, worksheets, receipts, returns, computer printouts, printed matter, prospectuses, statements, checks, statistics, surveys, affidavits, contracts, agreements. transcripts, magazines or newspaper articles or* press releases; (2) any electronically, magnetically, or mechanically stored material of any 'kind, including without limi~ation all electronic mail or e~mail, meaning any electronically transmitted lext or graphic communication created upon and transmitted or received by any computer or olher electronic device, and all materials stored on compact disk,* computer disk; diskette, hard drive, server, or tape; (3) any audio, aural, visual, or video records,

.recordings, or representations of any kind, including without limitation all cassette tapes, coinpact disks, digi'tal video disks, microfiche, microfilm, motion pictures, pictures, photographs, or videotapes; (4) any graphic materials and data compilations from which information can be obtained; (5) any materials using other means of preserving thought.

or expression; and (6) any tangible things from which data or information can be obtained, processed, recorded, or transcribed. The term "record" also includes any drafts, or alterations, amendments, changes, modifications of or to any of the foregoing.

lf it is your position that records exist that are responsive to this request, but that those records (or portions of those records) are exempt from disclosure under the FOIA, please identity the records that are being withheld and state the basis for the denial for each record ~eing withheld. In addition, please provide the non-exeinpt portions of the records.

Request for Waiver of Fees The Requesters hereby request that all fees in connection with thi.s FOIA request be waived for the following reasons: *

a. The requested disclosures concern the operations and activities of the.Federal Government because they seek information regarding the government's measurements of radiation levels in the aftennath of the radiological accident at Japan's Fukushima nuclear reactors.

Harmon, Curran, Spielberg + Eisenberg LLP C8X§XOO)

FOIA Officers March 22, 2011 Page 3

b. The disclosure of the requested measurements and analyses regarding radiation releases during the Fukushima accident *will significantly contribute to the public's.

understanding of the operations and activities of the DOE and the NRC with respect to nuclear regulatory matters. It is our understanding that the requested documents regarding airborne radiation levels informed the NRC's decision to* recommend the establishment of a SO-mile evacuation zone around the Fukushima reactors as the accident progressed. Given that U.S. emergency planning regulations require only a ten-mile evacuation zone, the public has a strong interest in learning what radiation levels would prompt U.S. govermnent officials to recommend more stringent measures for Japan. While DOE and NRC representatives have publicly discussed these measurements in very general terms, no actual measurements have been disclosed and thus it is not possible to evaluate the significance of the government's representations in any meaningful way. In addition, Requesters seek to evaluate the significance of radiological contamination of soil and water in Japan imd its potential effects beyond Japan:

The requested disclosures of criteria and protocols for the measurements and analyses will also contribute to public understanding of the government's operations because the information will help the public understand the reason for the apparent differences bet,:veen the U;S. and Jap~nese governments' assessments of the severity of the accident as it unfolded. An understanding of the methods by which the data were collected and analyzed will help members of the public evaluate the reliability of the reports they have received regarding airborne contamination. levels caused by the accident. All of the organizations have staff members who are experienced in evaluating information relating to radiological contamination and therefore have the capability to make good use of the information.*

All of the Requester organizations intend to publicize the requested information widely to

their thousands of members and visitors to the~r websites. FOE.(wm¥.foe.org), for example. is the worlq's larges grassroots environmental network, uniting 76 national member groups and some 5,000 local activist groups on every continent. NIRS

(,v,-vw.nirs.org) has over 25,000 members and its website receives on average of 1,500 visitors per day. PSR (www.psr.org) has 50,000 members and e*activists, thirty chapters, and a database of 250,000 concerned citizens dedicated to improving national policy formulation and decision-making about security, energy and the environment.

c. The requested documents will not be used for commercial use or gain by any of lhe Requester organizations. AH of the Requesters are non-profit organizations dedicated to protection of public health and the environment.

Harmon, Curran, Spielberg + Eisenberg LLP

~

FOTA Officers March 22, 2011 Page4 I.

If you decide not to grant a waiver, then please advise us of the amount of any proposed search. review, and reproduction charges before those activities are carried out.

Request for Expedited Consideration Reqttesters seek expedited release of.the requested information, so that they may timely inform their members and the general public about the unfolding events at the Fukushima reactors, including the significance of the public heafrh and.environmental threat posed by radiation releases from the Fukushima reactors. Requesters believe that requested disclosures will do a great deal to fill currently existing information gaps and resolve inconsistencies in the currently available reports a])out the severity of the Japanese .

radiological releases.

In addition, Requesters seek immediate disclosure of the information in order to participate in and comment on any proceedings the federal government may undertake to evaluate the lessons learned from the Fukushima accident. It is Requesters' ur:iderstanding, for example, that the NRC shortly intends to embark on a 90-day review of the safety of U.S. reactors and proposed designs in light of the Fukushima events. A better understanding of the severity of the Fukushima releases is essentialto Requesters' abilily to evaluate and participate in any such review.

ff some parts of this request can be responded to more quickly than others, we request thatyou re*spond in stages, releasing information as soon as it becomes available.

We will expect a response within 20* business days, as provided by 5 U.S.C. § 552(a)(6)(A)(i). If you have any questions regarding this request, please *contact me at (202) 328-3500.

Thank you very much for your attention to this matter.

1ane Curran Attomey for Requesters*

Cc: Tom Clements. FOE Michael Mar,iotte, NIRS Michele Boyd, PSR

FOIA Resource From:* Diane Curran [dcurran@harmoncurran.com]

Sent: Tuesday, March 22, 2011 4:25 PM To: FOIA Resource

Subject:

Freedom of Information Act Request; request for expedited consideration Attachments: FOE-NIRS-PSR FOIA Request for Radiation Survey documents 3-22-11.pdf

Dear FOIA Officer:

Attached please find a FOIA request, including a request for expedited consideration. Please call me if you have any questions.

Sincerely, Diane Curran Diane Curran Harmon Curran Spielberg & Eisenberg LLP 1726 M Street NW, Suite 600 Washington, DC 20036 (202)328-3500 1

NRC FORM 464 Part I U.S. NUCLEAR REGULATORY COMMISSION FOIA/PA RESPONSE NUMBER (4-2011) 201-1-0135 1 RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA) / PRIVACY ACT (PA) REQUEST

RESPONSE

TYPE D FINAL Ql l.!..J PARTIAL REQUESTER DATE Diane Curran AU8ttffll PART I. -- INFORMATION RELEASED D No additional agency records subject to the request have been located.. See Comments section.

D IRequested records APPENDICES are available through another public distribution program.

Agency records subject to the request that are-identified in the listed appendices are already available for D public inspection and copying at the NRC Public Document Room.

D 'APPENDICES I Agency records subject to the request that are identified in the listed appendices are being made available for public inspection and copying at the NRC Public Document Room.

~informatio~ on how you may obtain access to and the charges for copying record.s located at the NRC Public D ~E-n-cl-o-se_d_i_s Document Room, 11555 Rockville Pike, Rockville, MO 20852-2738 .

DI APPENDICES I. *Agency records subject to the request are enclosed.

Records subject to the request that contain Information originated by or of interest to another Federal agency have been D referred to that agency (see comments section) for a disclosure determination and direct response to you.

[lJ We are continuing to process your request.

[{] See Comments.

PART I.A - F.EES AMOUNT* 0 You will be billed by NRC for the amount listed. 0 None. Minimum fee threshold not met sI I 0 You will receive a refund for the amount listed. D Fees waived.

See comments for details PART I.B -- INFORMATION NOT LOCATED OR WITHHELD FROM DISCLOSURE D No agency records subject to the request have been located.

D ..the Certain information in the requested records is being withheld from disclosure pursuant to the exemptions described in and for reasons stated in Part II.

D . This determination may be appealed within 30 days by writing to the FOIAfPA Officer, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001. Clearly state on the envelope and in the letter that it is a "FOIA/PA Appeal:"

PART I.C COMMENTS (Use attached Comments continuation page If required)

Group G records relating to your request are being made publicly available In the "NRC Library" at.

http://www.nrc.gov/r eading-rm/foia/japan -foia~info.html.

As the NRC makes records publicly avallable, you will be notified in writing.

SIG~~ATU F EEDOM OF INFQi,,11,'ITIONA CTA~IVACY ACT OFFICER

,I I 1 .JJ \.0 -

M Jea apE~ l 1 NRC FORM 4641 Part 1 (4-2011)

Earthquakeffsunami Status Update March 12, 2011 1830 EST USNRC Emergency Operations Center Status Update*

March 12, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode.

On March 12, 2011, the NRC continues to operate in monitoring mode to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC staff are coordinating with several federal partners, including the White House, Congress, Departmentof Defense, Department of Energy, Department of Health and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, and Secret Service.

NRC is supporting USAID response efforts .. Two senior experts from NRC are. designated to be a part of an USAID delegation to.Japan to assist in the response and recovery efforts as necessary.

NRC liaison to the NRCC has ended.

NRC will request assistance from FEMA *REPP should the need arise.

NRC is also coordinating with the International Atomic Energy Agency.

NRC has issued 4 press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/readinq-rm/doc-,collections/news/2011/

Status of NRC Licensee and Agreement State Facilities Diablo Canyon Diablo Canyon Power Plant declared a Notice of Unusual Event at 0423 EST on March 11, 2011 based on receipt of a tsunami warning for the local coastal area.

1

O.~FICIAL *usE 01\JLY -

Earthquake/Tsunami Status Update March *12, 2011 1830 EST At 1130 EST, the licensee observed potential tsunami effects of 1 foot based on buoy information. The surge expanded to approximately three feet at its peak. This change was within the normal tidal range and did not impact plant operation.

On March 12, 2011, both units continue to operate at full power.

San Onofre Nuclear Generating Station (SONGS)

The effects of the tsunami at SONGS were negligible. SONGS was within the area of the tsunami advisory but did not reach any Emergency Action Level thresholds. On March 12, 2011, both units continue to operate at essentially full power.

Non-Power Reactors Category 1 and 2 sources in the states of California, Oregon, Washington, and Alaska were not impacted by the earthquake or tsunami. . ' .

The decommissioned Humboldt Bay nuclear plant prepared for any tsunami effects but was not impacted by the earthquake or tsunami.

Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and the International Atomic Energy Agency (IAEA)). *

Background:

There.are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, *5 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai)

Situation:

A magnitude 8.9 earthquake struck 80 miles east of Onagawa, 110 miles east-northeast of Fukushima at 1246 EST on March 11, 20'11. * ,

At the time of the earthquake:

all 3 units at Onagawa wer~ operating; all. 3 automatically shutdown 3 units at Fukushima Daiichi were operating (Units 1, 2, and 3, with Units 4, 5, and 6 in a maintenance outage); all 3 were automatically shutdown all 4 units at Fukushima Daini were operating; all 4 were automatically shutdown 1 unit operating at Takai; 1 ..unit was automatically shutdown .

At Onagawa, a fire was confirmed-to have occurred in the turbine building (turbine building common to all 3 units) .. This fire was extinguished.

At 0136 EST on March 12, 2011, a "vertical earthquake" resulted in an explosion at the Fukushima Daiichi Unit 1. Other units at Fukushima Daiichi and units at other sites were not impacted by this earthquake.

~-~OAEf'eFtrlC"'T'IAmtrnol't.'!S'CE'O::r,NillL'Y 2

Earthquake/Tsunami Status Update March 12, 2011 .1830 EST Current Understanding of Japanese Reactor Status . .

(This information is compiled from TEPCO press releases - March 121\ 9pm and 11pm, and March 13th, 2am) *

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. Radiation levels at the site boundary exceeded limits.

Winds are directed out to sea.

Unit 1 The reactor is shut down.

Explosion occurred at Unit 1 following 0136 EST (March 12, 2011) earthquake. This explosion was due to hydrogen.

At 0620 EST on March 12, 2011, operators began injection of sea water and boric acid into the reactor core. Thi~ combination acts to absorb neutrons in the reactor core, helping to stabilize the core.

Sea water is also being used to provide external cooling to the torus.

Indications of degrading core conditions are r:iot occurring.

Unit2 The reactor and the Reactor Core Isolation Cooling System are shut down.

Reactor water level is lower than normal, but the water level is steady. .

TEPCO is working with the Japanese national.government to reduce the pressure in the reactor containment.

Unit3 The reactor i~ shut down.

Water continues to be injected by the High Pressure Core Injection System.

TEPCO is working with the Japanese national government to reduce the pressure in the reactor containment.

TEPCO does not believe that. there is any reactor coolant leakage inside the reactor containment vessel.

Unit4 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO *does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

UnitS The reactor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit6 The reactor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained.

3 FICIAL U

OFFICIAL USE ONLY Earthquakeffsunami Status Update March 12, 2011 1830 EST TEPCO does not believe that there is any reactor coolant leakage inside the reactor

containment vessel.

Fukushima Daini .

Japanese national government instructed evacuation for local residents within a 10km radius of the site boundary. Radiation.levels-at the site boundary have*not exceeded limits.

Unit 1*

The reactor *is shut down.

A sufficient level of reactor coolant to ensure safety is maint~ined.

- TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit2 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to red.uce pressure in the reactor containment vessel.

The reactor was cold shut down at 2215 EST on March 11, 2011 Unit4 The reactor is shut down. ,

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

4

Earthquake/Tsunami Status Update March 12, 2011 2330 EST USNRC Emergency Operations Center Status Update March 12, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode.

On Ma*rch 12, 2011, the NRC continues to operate in monitoring mode to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC staff a.re coordinating with several federal partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, and Secret Service.

The two senior experts supporting USAID response efforts from the NRC are expected to arrive late tonight and early"tomorrow morning.

NRC is also coordinating with the International Atomic Energy Agency.

NRC has issued 4 press releases related to the earthquake and tsunami. *These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

Status of NRC Licens*ee and Agreement State Facilities Diablo Canyon Diablo Canyon Power Plant declared a Notice of Unusual Event at 0423 EST on March 11, 2011 based on receipt of a tsunami warning for the local coastal area.

At 1130 EST, the licensee observed potential tsunami effects of j foot based on buoy information. The surge expanded to approximately three feet at its peak. This change was within the normal tidal range and did not impact plant operation.

On March 12, 2011, bo_th units continue to operate at full power.

1

~ y

OFFICIAL USE ONLY Earthquakeffsunami Status Update March 12, 2011 2330 EST San Onofre Nuclear Generating Station (SONGS)

The effects of the tsunami at SONGS were negligible. SONGS was within the area of the tsunami advisory but did not reach any Emergency Action Level thresholds. On March 12, 2011, both units continue to operate.at essentially full power.

Non-Power Reactors Category 1 and 2 sources in the states of California, Oregon, Washington, and Alaska were not impacted by the earthquake or tsunami.

The decommissioned Humboldt Bay nuclear plant prepared for any tsunami effects but was not impacted by the earthquake or tsunami.

Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and the International Atomic Energy Agency (IAEA)}.

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa; 6 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Takai)

Situation:

A magnitude 8.9 earthquake struck 80 miles east of Onagawa, 11 O miles east-northeast of Fukushima at 1246.EST on March 11, 2011.

Afthe time of the earthquake:

all 3 units at Onagawa were operating; all 3 automatically shutdown 3 units at Fukushima Daiichi were operating (Units 1,* 2, and 3, with Units 4, 5, and 6 in a maintenance outage); all 3 were automatically shutdown all 4 units at Fukushima Daini were operating; all 4 were automatically shutdown 1 unit operating at Takai; 1 unit was automatically shutdown At Onagawa, a fire was confirmed to have occurred in the turbine buHding (turbine building

common to all 3 units). This fire was extinguished.

At 0136 EST on March 12, 2011, a "vertical earthquake" resulted in an explosion at the Fukushima Daiichi Unit 1. Other units at Fukushima. Daiichi and units at other sites were not impacted by this earthquake.

Current Understanding of Japanese Reactor Status .

(This information is compiled from TEPCO pre.ss releases - March 12th, 9pm and 11 pm, and March 131h, 2am) *

2

->F'F'ICIAL USE OMt:'V

~y Earthquake/Tsunami .

Status

. Update March 12, 2011 2330 EST Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. Radiation levels at the site boundary exceeded limits.

Winds are directed out to sea.

Unitl The* reactor is shut down.

Explosion occurred at Unit 1 following 0136 EST (March 12, 2011) earthquake. This explosion was due to hydrogen.

At 0620 EST on March 12, 2011, operators began injection of sea water and boric acid into

the reactor core. This combination acts to *absorb neutrons in the reactor core, helping to stabilize the core.

Sea water is also being used to provide external cooling to the torus.

The value of radioactive material (iodine, etc) is increasing according to the monitoring car at the site (outside of the site). One of the monitoring posts is also indicating higher than

normal level. . . .

Radiation levels at the boundary of the site exceeds limits,. clause 1 of the Article 15 of the Radiation *Disaster Measure declared.

Unit2 The reactor and the Reactor Core Isolation Cooling System are shut down.

Re~ctor water level is lower than normal, but the water level is steady.

TEPCO is working with the Japanese national government to reduce. the pressure in the reactor containment.

Unit 3 .

The reactor is shut down. . .

TEPCO is working with the Japanese national government to reduce the pressure in the reactor containment.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

-. TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level.

decreased exposing fuel.

Efforts to restart the Reactor Core Isolation Cooling System failed. Emergency Core Cooling System flow could no.t be confirmed. As such, at 5.10 AM, Mar 12, clause 1 of the Article 15 of the Radiation Disaster Measure Reactor containment is being vented to reduce pressure.

Unit4

The reactor is shut down.

A suffii;:ient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

UnitS

The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

.--- 3 OFFICIAL U81: ONLY

ONLY Earthquakerrsunami Status Update March 12, 2011 2330 EST TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel. **

Unit6 The reactor is shut down.

A 'sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Fukushima Daini Japanese national gov~mment instructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. Preparations to reduce Units 1, 2 and 3 reactor containment pressures (partial discharge of air. containing radioactive materials) are in progress. Unit 3 has been stopped and being "nuclear reactor cooling hot stopllat 12:15PM.

Unit 1 The reactor is shut down.

A sufficient level of reactor coolant to ensure s.afety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit2 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

The reactor was cold shut down at 2215 EST on March 11, 2011 Unit4 The reactor is shut down.

- A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in tt,e reactor containment vessel.

TEPCO prepared to reduce pressure in the reactor contai~ment vessel.

J 4

OF'F101t.L uge OMCv

Earthquake/Tsun ami Status Update March 13, 2011 0630 EST USNRC Emergency Operations Center Status Update March 13, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode.

On March 12, 2011, the NRC continues to operate in monitoring mode to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC staff are coordinating with several federal partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, and Secret Service.

The one of two senior experts supporting USAID response efforts from the NRC have arrived, the second is expected early this morning.

NRC is also coordinating with the International Atomic Energy Agency.

NRC has issued 4 press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

- Status of NRC ~icensee and Agreement State Facilities Diablo Canyon As of 1528 3/11 /11 Diablo Canyon Power Plant has exited its declared Notice of Unusual Event due to the tsunami warning; both units are operating at full power.

San Onofre Nuclear Generating Station (SONGS)

Both units are operating at full power.

Non-Power Reactors Category 1 and 2 sources in the states of California, Oregon, Washington, and Alaska were not impacted by the earthquake or tsunami. **

1 of 4 0FFIC17%L USE 01\JL'?

OEE!CIAL USE ONI Y---

Earthquakerrsunami Status Update March 13, 2011 .0630.EST The decommissioned Humboldt Bay nuclear plant prepared for any tsunami effects but was not impacted by the earthquake or tsunami.

At 5:26 PM Pacific Standard Time on March 12, an earthquake with preliminary magnitude 6.6 occurred off the east coast of Honshu, Japan. Based on the earthquake magnitude, location and historic tsunami records, a damaging tsunami IS NOT expected along the California,

Oregon, Washington, British Columbia, and Alaska coasts. NO tsunami warning, watch or advisory is in effect for these areas.

Q & A's have been developed to share with regional St.ate Liaison Officers to dialogue with state counterparts Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo-Electric Power Company (TEPCO) and the International Atomic Energy Agency (IAEA)) ..

Background*: _ . .. .

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, 6 at ~ukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai)

Situation:

A magnitude 8.9 earthquake struck 80 miles east of Onagawa, 110 miles east-northeast of Fukushima at 1246 EST on March 11-, 2011.

At the time of the earthquake:

all 3 units at Onagawa were operating; all 3 automatically shutdown 3 units at Fukushima Daiichi were operating (Units 1, 2, and 3, with Units 4, *5, and 6 in a maintenance outage); all 3 were automatically shutdown all 4 units at Fukushima Daini were operating; all 4 were automatically shutdown 1 unit operating at Tokai; 1 unit was automatically shutdown At Onagawa, a fire was confirmed to have occurred- in the turbine building (turbine building common to all 3 units). This fire was extinguished, At 0136EST on March 12,.2011, an explosion occurred at the Fukushima Daiichi Unit 1.

Current Understanding of Japanese Reactor Status 1

{This information is compiled from TEPCO press releases - March 12 \ 9pm and 11 pm, March 1

13 \ 2am, 8am, 9am and IAEA press releases) _

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary.

NISA press release (March 13, 2011 0830) stated four evacuees from Fatuaba - Machi have been found contaminated between 18000 and 40000 cpm.

2 of 4

OFFICIAL l:ISE

~ . ON[Y. .

Earthqua~errsunami Status Update March 13, 2011 0630 EST Winds cc;mtinue to blow out to sea.

Units 1 to 3: shutdown due to earthquake Units 4 to 6: shutdown due to outage .

Unit 1 .

The reactor is shut down. No offsite power, no emergency diesel generators working.

Explosion occurred at Unit 1 following 0136 EST (March 11, 2011) earthquake. *The.

containment remains intact. .

At 0620 EST on March 12, 2011, operators began injection of sea water and boric acid into the reactor core. This combination acts to absorb neutrons and cool the reactor core, helping to stabilize the core.

Sea water is also being used to provide external cooling to the torus.

The national government has instructed evacuation for those local residents within 20km radius *of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared. .

Radiation levels at the boundary of the site have been reported to be above background.

Unit2 The reactor is shut down and the Reactor Core Isolation Cooling System is injecting water.

Reactor water level is lower than normal, but above the top of-active fuel and the water level is steady.

TEPCO is working with the Japane~e nalional government to reduce the pressure in the reactor containment.

Unit3 The reactor is shut down. No offsite power, no emergency diesel generators working.

TEPCO is *working with the Japanese national government to reduce the pressure in the reactor containment. Containment remains intact.

TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level decreased exposing fuel.

Efforts to restart the Reactor Core-Isolation Cooling System failed: Emergency Core Cooling System flow could not be confirmed. .

The national government. has instructed evacuation for _those local residents within 20km radius of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared.

-

Alternative methods to inject water into the core are being investigated.

Containment sprays used to lower pressure within the reactor containment have been cancelled.

A reactor pressure vessel manual safety valve was opened to lower the reactor pressure and immediately followed by injection of sea water and boric acid into the reactor core.

TEPCO does not believe that there. is ariy reactor coolant leakage inside the reactor

. containment vessel.

Unit4 The reactor is shut down.

Sufficient level of reactor coolant to ensure safety is maintain.ed.

- .TEPCO does not believe that there is any reactor coolant-leakage inside the reactor containment vessel.

~ICIAL USE 0Nb¥ Earthquakeffsunami Status Update Marc~ 13, 20.11 0630 EST*

Unit5 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any rea~tor coolant leakage inside the reactor containment vessel.

Unit6

. The r~actor is shut doVJn. . .

A sufficient level of reactor coolant to ensure safety is maintained. . .

TEPCO does riot believe that there is ~ny reactor coolant leakage inside the reactor

. -containment vessel.

Fukushima Daini Japanese national government instructed evac.uation for local residents within a 10km radius of the site boundary. Radiation leveis at the site boundary* have riot exceedei°d Umits.

Unit 1 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the r~actor containment vessel.

Unit 2 The reactor iS Shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3 \

The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

The r~actor was in cold sh_utdown at 2215 EST on March 11, 2011 Unit4 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained .

. TEPCO prepared to reduce pressure in the reactor containment vessel.

TEPCO prepared to* reduce pressure in the reactor containment vessel. .

4 of 4

. OFFIGIAL I ISE ONJ)(

Earthquake/fsunami Status Update March 13, 2011 1400 EDT USNRC Emergency Operations Center St~tus Update March 13, 2011 Earthquake/ Tsunami Status Update Compiled by Executive Briefing Team USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC staff ar~ coordinating with federal partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, Naval Reactors, and Secret Service.

The two senior experts supporting USAID response effqrts from the NRC have arrived in Japan. The experts have engaged with the US Ambassador's staff and have started coordinating transfer of information from Japanese authorities to the US government.

NRC is also coordinating with the International Atomic Energy Agency.

Q & A's have been developed and shared with regional State Liaison Officers to dialogue with

state counterparts:

NRC has issued 5 press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects.

Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)).

1 of 4 Offi61AL USE Ord

EarthquakefTsunami Status Update March 13, 2011 1400 EDT

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, 6 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai)

Current Understanding of Japanese Reactor Status * .

1 (This information is compiled from TEPCO press releases - March 12 h, 9pm and 11 pm, March*

1 releases) 13 h, 2am, 8am, 9am, Opm, 1pm, 2pm, 3pm, and IAEA information Fukushima Daiichi Japanese national government instructed eyacuation for local residents .within a 20km radius of the site boundary.

The site is at a level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES).

A level 4 INES event can include or be characterized by:

Minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls.

At least one death from.radiation.

Fuel melt or damage to fuel resulting in more than 0. 1% release of core inventory.*

.,. Release of significant quantities of radioactive material within an installation with a higt, probability of significant public exposure.

Japan Nuclear and Industrial Safety Agency (NISA) press release (March 13, 2011 0830 JST) stated four evacuees from Fatuaba - Machi have been found contaminated between 18000 and 40000 cpm.

All available information indicates that releases from the Fukushima site have been carried out

. to sea by the prevailing winds. . .

Units 1 to 3: shutdown due to earthquake Units 4 to 6: shutdown due to outage Unitl

- The reactor is shut down. No offsite power, no emergency diesel generators working.

Explosion occurred at Unit 1 following 0136 EST (March 12, 2011) earthquake. The secondary containment was damaged.

At 0620 EST on March 12, 2011, operators began injection of sea water and boric acid into the reactor co*re. This combination acts to absorb neutrons and cool the reactor core, helping to stabiUze the core.

Sea water is also being used to provide external cooling to the torus.

Water level in the reactor is out of me~suring range, but at least 170 cm below the top of the core.

The national government has instructed evacuation for those local residents within 20km radius of the site periphery in accordance with clause 1. of thte Article 15 of the Radiation Disaster Measure declared. As of 1510 EST (March 12, 2011), an estimated 170,000 people have been evacuated. Full evacuation is not complete.

2 of4 OFFICIAL USE ONLY

OFF iCiAL USE ONLY Earthquake/Tsunami Status Update March 13, 2011 1400 EDT Radiation levels at the boundary of the site have been reported to be above background.

Radiation monitoring at 0020 EDT (March 13, 2011) indicates highest level is at measuring point MP4 of 47. 1 uSvlhour (4. 7 mremlhour). NISA confirmed presence of cesium-137 and iodine-131 in the vicinity of the site.

TEPCO is coordinating with Japanese authorities on how to cool down water in the spent fuel pool.

Unit2

Th.e reactor is shut down. and the Reactor Core Isolation Cooling System is injecting water.

Reactor water level is lower than normal, but above the top of active fuel and the water level is steady. Water level is approximately >375 cm above the top of the core.

- Working with the Japanese national government, TEPCO is taking measures to lower the pressure in the reactor containment.

Unit3 The reactor is shut down. No offsite power, no emergency diesel generators working.

TEPCO is working with the Japanese national government to reduce the pressure in the reactor containment. Containment remains intact.

TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level decreased exposing fuel. Reactor water level decreased to -150 to -200 cm below the top of the core.

Efforts to restart the Reactor Core Isolation Cooling System (high pressure injection) failed at 1510 EST (March 12, 2011). Emergency Core Cooling System flow could not be confirmed.

The national government has instructed evac~ation for those local residents within 20kni radius of the site periphery in accordance with clause 1 of the.Article 15 of the Radiation.

Disaster Measure declared.

- Alternative methods to inject water into the core are being investigated.

Containment sprays used to lower pressure within the reactor containment have been cancelled.

A reactor pressure vessel manual safety valve was opened to lower the reactor pressure.

The valve opening procedure ended at 1920 EST on March 12, 2011. This procedure was immediately followed at 1925 EST (March 12, 2011) by injection of sea water and boric acid into the reactor core.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit4

- The reactor is shut down.

Sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believ~ that there is any reactor coolant leakage inside the reactor containment vessel. *

Unit 5.

- The reactor is shut. down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactpr coolant leakage inside the reactor containment vessel.

QFFICIAI IJSE O~LY "

Earthquake/Tsunami Status Update March 13, 2011 1400 EDT Unit6 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor

containment vessel.

Fukushima Daini Japanese national government instructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST (March 12, 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is not complete.

Unit 1 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared, to reduce pressure in the reactor containment vessel.

Unit2

- The reactor is shut down. ,

- A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit 3 .

The reactor is shut down.

- A sufficient level of reactor *coolant to ensure safety is maintained, TEPCO prepared to reduce pressure in the reactor containment vesseL The reactor was in cold shutdown at 2215 EST on March 11, 2011 Unit4 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

- TEPCO prepared to reduce pressure in the reactor containment vessel.

Onagawa At 0530 EDT (March 1.3, 2011 ), Tohuku Electric Power Company notified the Japanese national government of an increased level of radiation of 21 uSv/hour (2. 1 mrem/hour) at the site boundary.

OFPIGh&:t:, USE ONLY E~rthquakeffsunami Status Update March 13, 2011 1(>00 EDT U.SNRC_l;mergency op,rations Center StJtus Update March 13, 2011 Earthquake/ T$unaml Status Update Cc>1npilecf by E~eclitive 8riefi11g T,am USNR,C Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations .Center is staffed;

NRC staff are coordinating With federa*1 partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health *and Human 'Services, Departm*ent of Homeland Security, Department of State, Department of Transportation, Envin;mmentat Prptection Agency,* Federal/Em~rgency Management Agency, Naval Reactors, and Secret Service. * * *

The two senior experts supporting USAID response efforts from the NRC have _arrived in Japatt The experts have engaged with the us Ambassador's staff and have started cc>0rd1nating transfer of information frorn Japanese authorities- to the us ;governrnent.

NRC is a1$0 co.ordinating with the International Atomic Energy Agency, Q & A'$ have been developed 111nd shared with regional $tate Liaison Officers to dialogue with state counterparts, NRC has issUed 5 press releases related to the earthquake and tsunami. These press releases can be found onlihe at http://www.nrc.gov/readlng-rm/doc-collections/news/2011/

Status of NRCLicensee .and Agree1~1:ent State F~cilities _

At this time, NRC 'is discontinuing reporting status of NRC licensee and Agreem_emt $tate facilities. NRC Will resume this teportii,g should any issues arise related to earthquake or tsunami .effects. * * *

Status of.Japanese *Facilities (This information is compiled from available sources, inc;:luding press releases by the Tokyo Electric Power Company (Tl:PCO) and information from the International Atomic Energy Agency {IAEA)). .(_

C:,'7

.. \

I

,I 1 .

O~LY Earthquakeffsunami Status Update March 13;*.2011 1600 EDT

Background:

There are 14 operational !3oiling Water .Reactors (BWRs) proximal to the earthquakEi zone (3 at Onagawa, 6 at.Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai)

Current Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases - March 12th, 9pm and 11 pm, March 13th, 2am, 8am, 9am, Oprri, 1prri, 2pm, 3pm, and IAEAinforrnationreleases}

. Fukush#na Daiichi .

Japanese national government instructed evacuation for local residents within a 20km radius of the site bounoary.

The site is at a level 4 "Accident with Local .Consequenc.es" on the \nternaticmal Nuclear am~

Radiological Event Scale (INES).

1 A level 4 INES event can include or be characterized by:

- *Minor release o.f radioillctive material unlikely to resu.lt in. implementation of plan,ned countermeasures* other than lcicalfood controls.

- At-lea$tone death from r~dic1tion. .

.,. Fuel. melt or damage to fuel resulting in more than 0.1 % release of core inventory.

Release of significant quantities of radioactive material within an installation with a high probapility of significant public exposure.

Japan Nuclear and Industrial Safety Agency (NISA) press release (March 13, 2011 0830 JST) stated four evacuees from Fatuaba - Machi have been found contaminated between 18000 and 40000 cpm.

All available information indicates that releases from the F4kushima site have been carried out

to sea by tne prevailing winds.

Units 1 to 3: shutdown due to earthquake Units 4_t~ 6: shutdown due to outage Unit1 The reactor is shut down. N<:> Offsite pow~r, no emerger,cy diesel generators working.

Explosion occurred at Unit 1 following 0136 EST,(March 12, 2011) earthquake. The secondary containment was damaged. * .

- At 0620 ESi cin March 12; 2011, qperato(S beg~n inj~clkm of sea water and bori~ acid into the reactor core. This combination acts to absorb neutrons and cooLthe' reactor core, heip1ng to stabilize the core. . . .

Sea water is also being used to* provide external cooling to the torus.

Water 'levelin the reactor is out of measuring range, but at least 170 cm below the top of the core.

- The naUonal government has instructed evacuation for those local residents within 20km __

radius of the $ite periphery ,n accordance with cJause 1 of the Article 15 of the Radiation

Disaster Measure declared. As of 1!;i10 EST (March 12, 2011), an estimated 170,000 people*have been evacuated. Full evacuation is not complete.

Radiation ievels at the boundary of the site have been reported to be above background; Radiation monitoring at 0020 EDT (March 13, 2011) indicates hig_hest level is at measuring 2 of 5 O~FICIAI l 1Sc ONP(

O.l;EICl4LlJg ONL!..

Earthquake/Tsunami Status Update March 13, 2011 1600 EDT point MP4 of47.1 uSv/hour (4.7 mrem/hour). NISA confirmed presence of cesium-137 and iodine-131 in the vicinity of the site.

- TEPCO is coordinating with Japanese authorities on how to cool down water in the spent fuel pool.

Unit2 The reactor is shut down and the Reactor Core Isolation Cooling System is injecting water.

Reactor water level is lower than normal, but above the top of active fuel and the water level is steady. Water level is approximately >375 cm above the top of the core.

Working with the Japanese national government, TEPCO is taking measures to lower the pressure in the reactor containment.

Unit3 The reactor is shut down. No offsite power, no emergency diesel generators working.

TEPCO is working with the Japanese national government to reduce the pressure in the reactor containment. Containment remains intact.

- TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level decreased exposing fuel. Reactor water level decreased to -150 to -200 cm below the top of the core.* *

Efforts to restart the Reactor Core Isolation Cooling System (high pressure injection) failed at 1510 EST (March 12, 2011 ). Emergency Core Cooling System flow could not be

. confirmed.

The national government has instructed evacuation for those local residents within 20km radiu~ of the site periphery in accordance with clause 1 of the Article 15 of the Radiation

Disaster Measure declared.

Alternative methods to inject water into the core are being investigated.

Containment sprays used to lower pressure within the reactor containment have been cancelled.

A reactor pressure vessel manual safety valve was opened to lower the reactor pressure.

The valve opening procedure ended at 1920 EST on March 12, 2011. This procedure was immediately followed at 1925 EST (March 12, 2011) *by injection of sea water and bori~ acid into the reactor core.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Un1t4

- The reactor is shut down.

Sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

UnitS The reactor is shut down.

- A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit6 The reactor is shut down.

Earthquakeffsunami Status Update March 13; 2011 1600:'EDT A sufficient ievel of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is ic!ny rea9tqr coo.lant leakage insid_e the reactor

containment vessel. * *

flikushima Daini Japanese national government instructed evacuation for local residents within a 1Okrn radius of the site boundary. Radiation levels at th~ site boundary have not exet;!eded'liir!its. As of 1510 EST (March 12, *2011 ), an estimated 30,000 people have been evact1ated. full evacuation is not complete. . .'

Unit 1 .

The reactor is shut down. ..

.. A .sufficlent level. of reactor coola.nt to ~nsure ~afety i~ maintained.

TEPCO prepared to reduce pressure in the reactor containm49nt vessel.

unit'2 .

The reactor- is shut down.

A sufficient level of reactor coolant to ensure safety is* maintained.

TEPCO prepared to reduce pressure iii the -reacforcontainn'.tent vessel.

Uhit3 The reacto{is shut down.

A sufficient level of reactor coolant to ensure safety is mc;1intained.

TEPCO prepared to reduce pressure in the reactor contain,ment vessel.

The reactor was in cold shutdownat:2.215 ESTonMarch 11, 2011.

Unit4 The reactor is shut down.

A sufficient ievel of reactor coQlaiit to ensure safety is. maintained.

- TEPCO preparecl to reduce pressure in the -reactor containment VE;iSSel.

Onagawa.

At 0530 EPT (M~rch 13, 2011), Tohuku Electric Power Company notified the Japanese. national government of an i.ncreased level of radiation of .21 oSv/hour (2.1 mrem/hour) atthe site boundary*.

NllC Evaluation ofR;idiatjon Measurements from the USS Ronald Reagan On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were approximately 0. 6 mrem per hour gamma with no measurable activity on. thfl ship -surfaces. Tt,e NRC had ff3ceived an IAEA *

.report showing dose r~tes of 100 rnremlhr at the ~ite bounda,ry measured .... 20 hcn1rs earlier and press reports for the previous day of plant venting. Given the metrological conditions; wind

. 4 of 5 OFFICIAL USE"C>NLY

Earthquake/Tsunami Status Upd!:!te March 13, 2011 1600 EDT speed of 3-5 mph and the calm 'Glass D and E' weather stability for the 20-24 hour time period, a plume with low dose rates from the venting is credible at this location.

The NRG staff determined that the measurable radioactivity was consistent with the venting of the Fukushima Daiishi Unit 1 reactor. The Navy also collected air samples having activity above background from the <<plume." The NRC staff determined that the "plume" was most likely a puff from the venting that contained long lived noble gases, Xe-133, Xe-135 and Kr-85.

The Navy is expediting the air samples to a base in Japan which can perform an isotopic analysis to determine the actual radio-nuclides. The NRCwi/1 be able to better determine the status of the reactor based on the nuc/ides found in the sample.

OA-ICIAL USE ONLY Earthqu~keffsunami Status Update March 13, 2011 . 2000 EDT USNRC Emergency Operations Center_Status Update March 13, 2011' Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution - This infor~ation may be dated and is subject to constant change.

USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC staff are coordinating with federal partners, ir,cluding the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, Naval Reactors, and* Secret. Service. * "*

The two senior exp~rts* supporting USAID response efforts from the NRC have arrived in Japan. The experts have engaged with the US Ambassador's staff and have started coordinating transfer of information from Japanese authorities to the US government.

NRC is also coordinating with the International Atomic Energy Agency.

NRC has issued 5 press releases related to the earthquake and tsunami, These press releases

can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011 /

Status ofNRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects. '

Status of Japanese Facilities (This information is compiled from available sources, including *press releases by the Tokyo Electric Ppwer Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)).

1 of 5 OFFICIAl:-t18_E_O_N_LY

O'FFICIAL USE ONLY Earthquakeffsunami Status Update March 13, 2011 2000 EDT

Background:

There are 14 operational Boiling Water Reactors (BWRs} proximal to the.earthquake zone (3 at Onagawa, 6 _at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai}

Current Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases - March 12'\ 9pm and 11 pm, *March 13th, 2am, 8am, 9am, Opm, 1pm, 2pm, 3pm, and IAEA information releases}

Fukushima Daiichi .

Japanese national government instructed evacuation for local residents within a 20km radius of th.e site boundary.

The site is at a levei" 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES}.

A level 4 INES event can include or be characterized by:

Minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls.

- At least one death from radiation.

Fuel melt or damage to fuel resulting in more than 0.1 % release of core inventory.

Release of significant quantities of radioactive material within an installation with a high probability of significant public exposure.

Japan Nuclear and Industrial Safety Agency (NISA) press release (March 13, 2011 0830 JST}.

stated four evacuees from Fatuaba - Machi have been found contaminated.

All available information indicates that releases from the Fukushima site have been carried out to sea by the prevailing winds.

Units 1 to 3: shutdown due to earthquake s:

Units 4 to shutdown due to outage All Units: lost all diesel generator fuel tanks and all AC power on-site.

Unit1 The reactor is shutdown. No offsite power, no emergency diesel generators working.

Explosion occurred at Unit 1 following 0136 EST (March 12, 2011) earthquake. The secondary containment was damaged. *

- At 0620 EST on March 12, 2011, operators began .injection of sea water and boric acid into the reactor core. This combination acts to absorb neutrons and cool the reactor core, helping to stabilize the core.

Sea water is also being used to provide external cooling to the torus.

Water level in the reactor is out of measuring range, but at least 170 cm below the top of the core.

The national government has instructed evacuation for those loca*1 residents within 20km radius of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared. As of 1510 EST (March 12, 2011), an estimated 170,000 people have been evacuated. Full evacuation is not complete.

Radiation levels at the boundary of th13 site have been reported to be above background.

NISA confirmed presence of cesium-137 and iodine-131 in the vicinity of the site.

~

OFFICIAL USE ONLY

.OF~Ab-US E-eN('(

Earthquakeffsunami Status Update March 13, 2011 2000 EDT

- TEPCO .is coordinating with Japanese authorities on how to cool down water in the spent fuelpool. * * *

Unit2 The reactor is shut down and the Reactor Core Isolation dooling Syst~m is injecting water.

Reactor water level is lower than normal, but above the top of active fuel and the water level is steady. Water level is approximately '>375 cm above the top of the core.

- Working with. the Japanese national government, TEPCO.is taking measures to lower the pressure in the reactor containment.

DC Power is stable.

Unit3

- The reactor is shut down. No offsite power, no emergency diesel generators working.

TEPCO is working with the Japanese n~tional government to reduce the pressure in the reactor containment. Containment remains intact.

TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level decreased exposing fuel. . Reactor water level decreased to -150 to -200 cm below the top of the core.

Efforts to restart the Reactor Core Isolation Cooling System (high pressure injection) failed at 1510 EST (March 12, 2011). Emergency Core Cooling System flow could not be confirmed. Core damage likely. . *

The national government has instructed evacuation for those local residents within 20km radius of the s.ite periphery in accordance with clause 1 of the Article' 15 of the Radiation Disaster Measure *declared.

Alternative methods to inject water into the core are being investigated.

Containmenf sprays used to lower pressure within the reactor containment have been cancelled. . .

A reactor pressure vessel manual safety valve was opened to lower the reactor pressure.

The valve opening procedure ended,at 1920 EST on March 12, 2011. This procedure was imn:iediately followed at 1925 EST (March 12, 2011) by injection of sea water and boric acid into the reactor core (uncertain of success); .

_TEPCO does not believe that there is any reactor coolant leakage inside the* reactor con~ainment vessel. * * *

Unit4

- The reactor is shut down. _

Sufficient level of reactor coolant to ensure safety is maintained. *

- TEPCO does not believe that there is any reactor coolant leaka*ge inside the reactor containment vessel.

UnitS

- The reactor is shut down. . . .

A sufficient level of reactor coolant to ensure safety is *maintained.

- TEPCO does not believe that thetre is any reactor coolant leakage inside the reactor contai.nment vessel.

Unit6

- The reactor is shut down.

- A sufficient level of _reactor coolant to ens~re safety is maintained.

3 Of 5

Earthquake/Tsunami Status Update March 13, 2011 2000 EDT TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Fukushima Daini .

Japanese national government instructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST (March 12, 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is not complete. *

Unit 1 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit2

- The reactor is shut down.

- A sufficient level of reactor coolant to ensure safety is maintained ..

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit 3 ,

- The reactor is shut down.

- A sufficient level of reactor coola*nt to ensure safety is maintained.

- TEPCO prepared to reduce pressure in the reactor containment vessel.

- The reactor was in cold shutdown at 2215 EST on March 11, 2011 Unit4

- The reactor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained.

- TEPCO prepared to reduce pressure in the reactor containment vessel.

Onagawa At 0530 EDT (March 13, 2011), Tohuku Electric Power Company notified the Japanese national government of an increased level of radiation of 21 uSv/hour (2.1 mrem/hour) at the site boundary.

4 of 5 LUSE O Y

NRCN EWS U.S. NUCLEAR REGULATORY COMMISSION Office of Public Affairs Telephone: 301/415-8200 Washington, D.C. 20555-0001 E-mail: opa.resource@nrc.gov Site: www.nrc.gov Blog: http://public-blog.nrc-gateway.gov No. 1-1-046 March 13, 2011

.(Revised)

NRC SEES NO RADIATION.AT HARMFUL LEVELS REACHING U.S.

FROM DAMAGED JAPANESE NUCLEAR POWER P~ANTS The Nuclear Regulatory Commission is coordinating with the Department of Energy and other federal agencies in providing whatever assistance the Japanese government requests as they

\ respond to conditions at several nuclear power plant sites following the March 11 *earthquake and tsunami. The NRC has sent two boiling-water reactor experts to Japan as part of a U.S. Agency for International Development team.

In response to nucle~r emergencies, the NRC works with other U.S. agencies to mo~itor radioactive releases and predict their path. All the available information indicates weather conditions have taken the small releases from the Fukushima reactors out to sea away from the population. Given the thousands of miles between the two countries, Hawaii, Alaska, the U.S.

Territ~ries and the U.S. West Coast are not expected to experience any harmful level~ of )

radioactivity. **

During a nuclear event the NRC has requirements to protect populations around reactors:

For inst!,nce, the U.S. evacuation standard at 10 miles is roughly equivalent to the 20-kilometer distance recommended in Japan. The United States also uses sheltering in place and potassium iodide, protective measures also available in Japan. United States citizens in Japan ar~

encouraged to follow the protective measures recommended by t}i.e Japanese government. These*

measures appear to be consistent with steps the United States would take.

The NRC will not comment on hour-to-hour developments at the Japanese reactors. This is an ongoing crisis for the Japanese who have primary responsibility.

I News releases are available through a free listserv subscription at the following Web address:

http://www.nrc.gov/public-involve/listserver.html. The NRC homepage at www:nrc.gov also offers a SUBSCRIBE link. E-mail notifications are sent to subscribers when news releases are posted to NRC's website.

OFFICIAL USE ONLY Earthquakef f sunami Status 'Update March 13, 2011 2200 EDT USNRC Emergency Operations Center Status Update March 13, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be dated and is subject to constant change.

USNRC Status*

At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC staff are coordinating.with federal par1ners, including the White House, Congress, Department of Defe.nse, Department of Energy, Department of Healtti and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, Naval Reactors, and Secret Service.

The two senior expe*rts supporting USAID response efforts from the NRC have arrived in Japan.

The *experts have engaged with the US Ambassador's staff and have started coordinating transfer of information from Japanese authorities to the US gov~rnment.

I .

NRC is also coordinating with the International Atomic Energy Agency.*

Q & A's have been developed and shared with Regional State Liaison Officers tq dialogue with stat.e counterparts.

NRC has issued 5 press releases related to the earthquake and tsunami. These press releases can *be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011 /

Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami I

effects.

1 of 5 OFFICIAL USE ONLY*

OFFICIAL USE ONLY; Earthquake/Tsunami Status Update March 13, 2011 2200 EDT Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)).

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, _6 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Takai)

Current Understanding of Japanese Reactor Status *

(This information is compiled from TEPCO press releases - March 1ih, 9pm arid 11pm, March 131\ 2am, earn, 9am, Opm, 1pm, 2pm, 3pm, 8pm, and 9pm, and IAEA information releases)

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. .

The site is at *a level 4 "Accident with Local Consequerices" on the International Nuclear ~nd Radiological Event Scale (INES).

A level 4 INES event can include or be ch~racterized by:

Minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls.

At least one death from radiation.

Fuel*melt or damage to fuel resulting in more than 0.1 % release. of core inventory.

Release of significant quantities of radioactive material within an installation with a high probability of significant public exposure.

Japan Nuclear and Industrial Safety Agency (NISA) press release (March 13, 2011 0830 JST) stated four evacuees from Fatuaba - Machi have been found contaminated between 18000 and 40000 cpm.

All available information indicates that releases from the Fukushima site have been carried out

to sea by the prevailing winds.

Units 1 to 3: shutdown due to earthquake Units 4 to 6: shutdown due to outage All Units: lost ~II diesel generator fuel tanks and all AC power on-site.

Unltl .

The reactor is shut down. No offsite power, no emergency diesel generators working.

Explosion occurred at Unit 1 following 0136 EST (March 12, 2011) earthquake. The secondary containment was damaged.

At 0620 EST on March 12, 2011, operators began injection of sea water and boric acid into

the reactor core. This combination acts* to absorb neutrons and cool the reactor core, helping to stabilize the core.

Sea water is also being used to provide external cooling to the torus.

Water level in the reactor is out of measuring range, but at least 170 cm below the top of the core.

. 2 of 5 OFFICIAL USE ONLY I

I~

~

OFFICIAL USE ONLY Earthquakeffsunami Status Update March 13, 2011 2200 EDT

- The national government has instructed evacuation for those local residents within 20km radius "of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared. As of 1510 EST {March 12, 201.1), ari estimated 170,000 people have been evacuated. Full evacuation is not complete .

. Radiation levels at the* boundary of the site have been reported to be above background.

Radiation monitoring at 0020 EDT {March 13, 2011} indicates highest level is at measuring point MP4 of 47 .1 uSv/hour (4. 7 mrem/hour). NISA confirmed presence of cesium-137 a*nd iodine-131 in the vicinity of the site.

- TEPCO is coordinating with Japanese authorities on how to cool down water in the spent fuel pool.

Unit2 The reactor is shut.down and the Reactor Core Isolation Cooling System is injecting water.

Reactor water.level is lower than normal, but above the top of active fuel and the water level*

is steady. Water level is approximately >375 cm above the top of the core.

Working with the Japanese national government, TEPCO is taking measures to lower the pressure i'1 the reactor containment.

DC Power is stable. . **

Unit3 The reactor is shut down. No offsite power, no emergency diesel generators working.

TEPCO is working with the Japanese national government to reduce.the pressure in the reactor containment. Containment remains intact. *

.TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level decreased exposing fuel. Reactor water level decreased to -150 to -200 cm .below the top of the core.

Efforts to restart the Reactor Core Isolation Cooling System (high pressure injection) failed at 1510 EST {March 12, 2011 ). Emergency Core Cooling System flow could not be confirmed. Cor.e damage likely.

The national government has instructed evacuation for those local residents within 20km radius of the site periphery in accordance with clause 1 of the Article.15 of the Radiation Disaster Measure declared. .

Alternative methods to inject water into the core are being investigated.

Containment sprays used to lower pressure within the reactor containment have been cancelled. .

A reactor pressure vessel manual safety valve was opened to lower the reactor pressure.

The valve opening procedure ended at 1920 EST on March 12, 2011. This procedure was immediately followed at 1925 EST (March 12, 2011) by injection of sea water and boric acid into the reactor core (uncertain of success).

TEPCO do,es not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit4

-

The reactor is shut down.

Sufficient level of reactor coolant to ensure _safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

3 of 5

. OFFICIAL USE ONLY

OFFICIAL USE ONLY Earthquake/Tsunami Status Update March 13, 2011 2200 EDT Units The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is. any reactor coolant leakage inside the reactor containment vessel. *

Uhlt6 .

The reactor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor *coolant leakage inside the reactor containment vessel. *

Fukushima Daini Japanese national governmentinstructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 151 O EST (March 12, 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is not complete. . .

Unitl The reactor is shut down.

A sufficient level of reactor coolant to ensure safety. is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit2

The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

The reactor was in cold shutdown at 2215 EST on March 11, 2011 Unit4 The reactor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained. ..

TEPCO prepar~d to reduce *pressure in the reactor containment vessel.

Onagawa*

At 0530 EDT (March 13, 2011 ), Tohuku Electric Power Company notified the J~panese national government of an increased level of radiation of 21 uSv/hour (2.1 mrem/hour) at the site boundary.

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L

OFFICIAL USE ONLY Earthquakeff sunami Status Update March 13, 2011 2200 EDT NRC Evaluation of Radiatic,>n Measurements from the USS Ronald Reagan On the morning of March 13, 2011., Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem per hour

.gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hr up wind at the site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months earlier and press reports for the previous day of plant venting. Given the metrological conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time _

period, a plume with low dose rates from the venting is credible at this location.

The NRC staff determined that the measurable radioactivity was consistent with the venting of the Fukushima Daiishi Unit 1 reactor. The Navy also collected air samples having activity above background from the "plume."

The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determine the actual radio-nuclides. The principle radionuclidesident ified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

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.Earthquake/Tsunami Status Update March 13, 2011

2230 EDT

. USNRC Emergency Operations Center Status Update.

March 13, 2011 l;arthquake / Tsunami Status Update Compiled by Executive Briefing Team

./ '

Caution - This infQrlilation may be dated and is subject to constant change.

Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 201'1, the NRC entered Monitoring Mode and the agency continues .to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC staff are coordinating with federal partners, including the White Houl?e, Congress,

. Department of Defense, Department of Energy, Department of.Health and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency ManagemenJ Agency, Naval Reactors, and Secret Service. .

The two senior experts supporting USAID response efforts from the NRC have arrived in Japan.

The experts have engaged with the US Ambassador's staff and* have started coordinating transfer of information from Japanese authorities to the US government.

NRC is also coordinating with the International Atomic Energy Agency.

Q & A's have been developed and shared with Regional State Liaison Officers to dialogue with state counterparts.

NRG has issued 5 press releases related to the earthquake and tsunami. These press releases can be found o~line at: http.:1/www.nrc.gov/reading-rm/doc-collections/news/2011/

Status of NRC Licensee and Agreement State Facilities At this-time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise r.elated to earthquake or tsunami effects. * *

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QEFICIAI USE ONCY Earthquake/Tsunami Status Update March 13, 2011

2230 EDT Status of Japanese Facilities (This fnformation is compiled from available sources, including press *releases by the Tokyo Electric Power Company {TEPCO) and information from the International Atomic Energy Agency (IAEA)).

Background:

There are 14 operational Boiling Water Reactors {BWRs) proximal to the earthquake zone (3 at Onagawa, 6 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai)

Current Understanding of Japanese Reactor Status .

(This information is compiled from TEPCO press releases - March 1th. 9pm and 11 pm, March 131h, 2am, 8am, 9am, Opm, 1pm, 2pm, 3pm, 8pm, and 9pm, and IAEA information releases)

Fukushima Daiichi .

Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. *

The site is at a level 4 "Accident with Local Consequ~nces" on the International Nuclear and Radiological Event Scale (INES).

A level 4 INES event can include or be characterized by:

Minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls.

At least one death from radiation.

Fuel melt or damage to fuel resulting in more than 0.1 % release of core inventory:

Release of significant quantities of radioactive material within an installation with a high probability of significant public exposure. ,

Japan Nuclear and Industrial Safety Agency {NISA) *press release {March 13, 2011 0830 JST) stated four evacuees from Fatuaba - Machi have been found contaminated between 18000 an!'.1 40000 cpm.

All available information indicates that releases from the Fukushima site have been carried out to sea .by the prevailing winds ..

Units 1 to 3: shutdown due to earthquake Units 4 to 6: shutdown due to outage

All Units: lost all diesel generator fuel tanks and all AC power on-site.

Unit 1 .

- The reactor is shut down. No offsite power, no emergency diesel generators working.

Explosion occurred at Unit 1 following. 0136 EST (March 12, 2011) earthquake. The secondary containment was damaged. .

- At 0620 EST on March 12, 2011, operators began injection of s~a water and boric acid into the reactor core .. This combination acts to absorb neutrons and cool the reactor core, helping to stabilize the core.

Sea water is also being used to provide external cooling to the torus.

- Water level in the reactor is out of -measuring range, but at least 170 cm below the top of the core; 2 of 5 OFFICIAL USE OMLY-

O~ICIAL USE ONLY ~

'Earthquake/Tsunami Status Update March 13, 2011 22~0 EDT The national government has instructed evacuation for those local residents within 20km .

radius of the sjte periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared. As of 1510 EST (March 12, 2011), an.estimated 170,000

people have been evacuated. Full evacuation is not complete.

Radiation levels at the boundary of the site have been reported to be above background.

Radiation monitoring at 0020 EDT (March 13, 2011) indicates highest level is at measuring point MP4 of 47.1 uSv/hour (4.7 mrem/hour). NISA confirmed presence of cesium-137 and iodine-131 in the vicinity of the site. **

TEPCO is coordinating with Japanese authorities on how to cool down water in the spent fuel pool.

Unit 2 The reactor is shutdown and the Reactor Core Isolation Cooling System is injecting water.

Reactor water level is lower than normal, but above the top of active fuel and the water level is steady. Water level is approximately >375 cm above the top of the core.

Working with the.Japanese national government, TEPCO is taking measures to .lower the pressure in the reactor containment.

DC Power is stable ..

Unit 3 .

The reactor is shut down. No offsite power, no emergency diesel generators working.

TEPCO is working with the Japanese national government to reduce the pressure in the reactor containment. Containment remains intact.

TEPCO informed Japanese Cabinet that Unit 3 water injection stopped .and water level decreased exposing fuel. Reactor wat~r level decreased to -150 to -200 cm below the top ofthe core.

Efforts to restart the Reactor Core Isolation Cooling System (high pressure injection) failed at 151 o EST (March 12; 2011 ); Emergency Core Cooling System flow could not be confirmed. Core dama*ge likely.

The national government has instructed evacuation for those _local residents within 20km radius of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared.

Alternative methods to inject water into the core are being investigated.

Containment sprays used to lower pressure within the reactor containment have been cancelled. .

A reactor pressure vessel manual safety valve was opened to lower the reactor pressure.

The valve opening procedure ended at 1920 EST on March 12, 2011. This prqcedure was immediately followed at 1925 EST (March 12, 2011) by injection of sea water and boric acid into the reactor core (uncertain of success).

TEPCO does not believe that there is .any reactor coolant leakage inside the reactor

containment vessel. .

At approximately 2200 EDT (March 13, 2011) there was a hydrogen explosion at Unit 3.

Unit4 The reactor is shut down.

Sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

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Earthquakeffsunami Status Update March 13, 2011 2230 EDT I

UnitS The reactor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained ..

TEPCO does not believe that there is any reactor coolant leakage inside the reactor

. containment vessel.

Unit6 The reactor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel. * *

Fukushima Daini Japanese national government instructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST (March 12, 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is not complete.

Unit 1 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is .maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit2 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3

The reactor is shut qown.

A sufficient level of-reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

The reactor was in cold shutdown at 2215 EST on March 11, 2011 Unit4 TheJeactor is'shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor cqntainment vessel.

Onagawa At'0530 EDT (March 13, 2011 ), Tohuku Electric Power Company notified the Japan~se national.

government of an increased level of radiation of 21 uSv/hour (2.1 mrem/hour) at the site boundary.

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OFFICIAL U5t:: or~

Earthquakeffsunami Status Update March 13, 2011 2230 EDT NRC Evaluation of Radiation Meastllrements from the USS Ronald R~agan On the morning of Maren 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the

Japanese coast. Dose rates from the overhead "plumeu were approximately 0.6 mrem per hour gamma with no measurable activity on t.he ship surfaces. The NRC had received a11 IAEA report showing dose rates of 100 mrem/hr up wind at the* site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months earlier and press reports for the previous day of plant venting. Given the metrological conditions; wind speed of 3-5 *mph and the calm 'Class D and E' weather stability-for the 20-24 hour time period, a plume with low dos.e rates froll'.l the venting is credible at this location.

The NRC staff determined that the measurable radioactivity was consistent with the venting of the Fukushima Daiishi Unit 1 reactor. The Navy also collected air samples having activity ab9ve background from the "plume." *

The. Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determine the adual radio-nuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

. OF'FICIAL USE 01\JLV "°"

Earthquake/fsun~mi Status Update March 14, 2011 0430 EDT USNRC Emergency Operations Center Status Update March 14, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be dated and is subject to constant change.

Changes/Additions from previous updates a~e underlined USNRC Status At 0946 EST, March 11, ~011, the NRC entered Monitoring Mode and the agency continues to*

monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC is coordinating with federal partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services, -Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, Naval Reactors, and Secret Service. "

The two senior experts supporting USAID response efforts from the NRC have arrived in Japan.

The experts have engaged with the US Ambassador's staff and have started coordinating transfer of information from Japanese authorities to the US government.

. NRC is also coordinating with the International Atomic Energy Agency.

Q & A's have been developed and shared with Regional State Liaison Officers to dialogue with state counterparts.

NRC has issued 5 press releases relat~d to the earthquake .and tsunami. These press releases can be found online at: http://www.nrc.gov/reading~rm/doc~collections/news/2011 /

Status of NRC Licensee a:nd Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement- State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects.

_ 1 of5 OFFICIAL USE ONLY

_9.EEIC~

Earthquakerrsun ami Status Update March 14, 2011 0430 EDT Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)).

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, 6 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai)

Current Understanding of Japanese Reactor Status .

(This information is compiled fr9m TEPCO press releases - March 121\ 9pm and 11 pm; March 131\ 2am, 8am, 9am, Opni, 1pm, 2pm; 3pm, 8pm, anq 9pm; and IAEA information releaset) ..

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place for residents who stayed behind.

The site is at a level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES).

A level 4 INES event can include or be.characterized by: . .

Minor release of radioactive material unlikely to result in implementation- of planned countermeasures other than lo.cal food controls.

At least one death from radiation.

Fuel melt or damage to fuel resulting in more than 0.1 % release of core inventory.

Release of significant quantities of radioactivErmaterial. within an installation with a high probability of significant public exposure:

All available information indicates'that.*releases from the Fukushima site have been carried out to sea by the prevailing Winds.

Units 1, 2, and 3: shutdown due to earthquake.

At approximately 0230 EDT {March 14, 2011) received report from the NRC expert at the US Embassy in Tokyo that cooling capability has been lost to all three units* for *

several hours. Units 1 and 3 have lost the ability to inject seawater into the reactor ~nd containment. Unit 2 has lost the ability to maintain core cooling using the Reactor Core Isolation Cooling System (RCIC).

The reactor cores of all three units remain covered, but core cooling is currently unavailable. *

Units 4, 5, and 6: shutdown due to out~ge .

All Unit~: lost all diesel generator fuel tanks a'nd all AC power on-site.

Unit 1 The reactor is shut down. No offsite power, no _emergency diesel generators working.

Explosion occurred at Unit i following 0136 EST (March 12, 2011) earthquake. The secondary containment was damaged.

) 2 of 5

0-Y

Earthquake/Tsunami Status Update March 14, 2011 0430 EDT At 0620 EST on March 12, 2011, 9perators began injection of sea water and boric acid into the reactor core. This combination acts to absorb neutrons and cool the reactor core, helping to stabilize the core.

Sea water was also being used to provide external cooling to the torus.

At approximately 0230 EDT on March 14, 2011, NRC received information that Unit 1 has lost the ability to inject seawater into the reactor and containment.

The reactor core remains covered, but seawater injection has been unavailable for several hours.

The national government has instructed evacuation .for those local residents within 20km radius of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared. As of 1510 EST (March 12, 2011 ), an estimated 170,000 people have been evacuated. Full evacuation is not complete.

Radiation levels at the boundary of the site have been reported to be above background.

Radiation monitoring from 0825 local time (March 13. 2011) to 0338 local time (March 14.

2011) indicates highest level is at measuring point MP4 (Plant site, upwind of venting release points) of 1200 uSv/hour (120 mrem/hour) and a background of approximately 40 mr/hour with 120 mr/hour during venting. NISA confirmed presence of cesium-137 and iodine-131 in the vicinity of the site.

TEPCO is coordinating with Japanese authorities on how to cool down water in the spent .

fuel pool.

Unit 2.

The reactor is shut down and the Reactor Core Isolation Cooling System is injecting wate~.

Reactor water level is lower than normal, but above the top of active fuel and decreasing.

Working with the Japanese national government, TEPCO is taking measures to lower the pressure in the reactor containment .!2Y. venting.

DC Power is stable.

At approximately* 0230 EDT on March 14, 2011. the NRC senior expert reported that the core*remains covered. but RCIC is unable to maintain level due to unreliable operation.

RCIC has been unavailable for several hours.

Japanese officials have informed the public of the possibility of a hydrogen explosion as a result of the loss of cooling.

Unit3 The reactor.is shut down. No offsite power, no emergency diesel generators working.

TEPCO is working with the Japanese national government to reduce the pressure in the reactor containment. Containment remains intact.

TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level decreased exposing fuel. Reactor water level decreased to -150 to -200 cm below the top of the core, but have since been raised above the top of active fuel.

Efforts to restart the Reactor Core Isolation Cooling System (high pressure injection) failed at 1510 EST (March 12, 2011). Emergency Core Cooling System flow could not be confirmed. Core damage likely. .

The national government has instructed evacuation for those local residents within 20km radius of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared. * .

Alternative methods. to inject water into the core are being investigated.

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OF~

Earthquakeffsunami Status Update March 14, 2011 0430 EDT Containment sprays used to lower pressure within the reactor containment have been*

. cancelled. *

~ A reactor pressure vessel manual safety valve was opened to lower the reactor pressure.

The valve opening procedure ended at 1920 EST on March 12, 2011. This procedure was immediately followed at 1925 EST (March 12, 2011) by injection of sea water and boric acid into the reactor core (uncertain of success). "

At approximately 0230 EDT on March 14, 2011, NRG received information that Unit 3 has lost the ability to inject seawater into the reactor and containment. ..

The reactor core remains covered, but levels are decreasing.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

At approximately 2200 EDT (March 13; 2011) there was a hydrogen explosion at Unit 3 that damaged the secondary containment.

Unit4

. The reactor is shut down.

Sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit 5 The reactor is shut down .

.A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit 6 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Fukushima Daiiri -

Japanese national government instructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST (March 12, 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is *

-not complete. The Daini units have AC power, but have lost their Ultimate heat sink.

Unit 1 The reactor is shut down.*

A sufficient_ level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit2 The reactor is shut down.

A sufficient level of reactor co_olant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

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OF~Y Earthquakeffsunami Status Update March 14, 2011 0430 EDT Unit3 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

The reactor was in cold shutdown at 2215 EST on March 11, 2011 Unit4 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Onagawa At 2145 CET (March 13, 2011 ), IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels .

. NRC Evaluation of Radiation Measurements from the USS Ronald Reagan On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the. flight deck of the USS Reagan that was -130 nautical miles off the

Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem per hour gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report ~howing dose rates of 100 mrem/hr up wind at the site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months

earlier and press reports for the previous day of plant venting. Given the metrological conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with low dose rates from the venting is credible at this location.

NRC staff. believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from Japanese officials during venting from Fukushima Daiichi Units 1, 2. and 3.

a The Navy sent the contamination samples to base in Japan to perform an isotopic analysis to determine the actual radio-nuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US 7th Fleet has repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area. * *

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~FICIAL I !SF ONLY, Earthquake/Tsunami Status Update March 14, 2011 0600-EDT U~NRC Emergency Operations Center Status Update March 14, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be dated and is subject to constant change.

Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 201 i, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC is coordinating with federal partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services, Department of Homeland Security, Department of State, Department of Transpe>rtation, Environmental*

Protection Agency, Federal Emergency Management Agency, Naval Reactors, and Secret

~N~. . . .

The two.senior experts supporting USAID response efforts from the NRC have arrived in Japan.

The experts have engaged with the US Ambassador's staff and have started coordinating transfe~ of information from Japanese authorities to the US government.

At 0550 EDT, the NRC experts in Japan reported that the Japanese have requested US technical assistance with cooling the Fukushima Daiichi Units 1, 2, and 3, which have been without cooling for approximately 18 hours2.083333e-4 days 0.005 hours 2.97619e-5 weeks 6.849e-6 months . The effort is being coordinated by the US *.

Ambassador. r

NRC is also coordinating with the International Atomic Energy Agency.

Q & A's have been developed and shared with Regional State Liaison Officers to dialogue with state counterparts. *

NRC has issued 5 press releases related to the earthq.uake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects.

1 of 5

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.\

OrFIGIAb I !SE GtdLY '

Earthquake/T sunami Status Update March 14, 2011 0600 EDT Status of Japanese Facilities (This infqrmation is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)). *

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, 6 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Tokai)

Current Understandin g of Japanese Reactor Status * .

1 (This information is compiled from TEPCO press releases - March 12 \ 9pm and 11 pm, March

. 2pm, 3pm, 8pm, and 9pm,. and IAEA information releases) 1 13 \ 2am, 8am, 9am, Opm, 1pm, Fukushima Daiichi Japanese national government instructed evacu~tion for local residents within a 20km radius of the site boundary and .sheltering in place for residents who stayed behind.

The site is at a* level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES).

A level 4 INES event can include or be characterized by:

Minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls.

At least one death from radiation.

Fuel melt or damage to fuel resulting in more than 0.1 % rel.ease of core inventory..

Release of significant quantities of radioactive material within an installation with a high probability of significant public exposure. .

_: All. available information indicates that releases from the Fukushima site have been carried out to sea by th~ prevailing winds.

Units 1, 2, and 3: shutdown due to earthquake approximately 0230 EDT (Marc;h 14, 2011) received report from the NRC expert at the US Embassy in Tokyo that cooling capability has been lost to all three units for several hours. Units 1 and 3 have lost the ability to inject seawater into the reactor and containment. Unit 2 has lost the ability to maintain core cooling using the Reactor Core Isolation Cooling System (RCIC). ..

The status of core coverage for all three units is highly uncertain.

Units 4, 5, and 6: shutdown due to outage All Units: lost all diesel generator fuel tanks and all AC power on-site.

Unitl The reactor is shut down. No offsite power, no emergency diesel generators working.

Explosion occurred at Unit 1 follovving 0136* EST (March 12, 2011) earthquake. The

secondary containment was damaged.

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.I C°FRcl41 I !SE Qf)JLY Earthquake/Tsunami Status Update March 14, 2011 0600 EDT At 0620 EST on March 12, 2011, operators began injection of sea water and boric acid into the reactor core. This combination acts to absorb neutrons and cool the reactor core, helping to stabilize the core.

Sea water was also being used to provide external cooling to the torus.

At approximately 0230 EDT on March 14, 2011, NRC received information that Unit 1 has lost th.e ability to inject seawater into the reactor and containment.

The status of.core coverage highly uncertain.

The national government has instructed evacuation for those local residents within 20km

radius of the site periphery in. accordance with clause 1 of the Article 15 of the Radiation

Disaster Measure declared. As of 1510 EST (March 12, 2011 ), an estimated 170,000 people have been evacuated. Full evacuation is not complete.

Radiation levels at the boundary of the site have been reported to be above background.

Radiation. monitoring from 0825 local time (March 13, 2011) to 0338 local time (March 14, 2011) indicates highest level is at measuring point MP4 (Plant site, upwind of venting release points) of 1200 uSv/hour (120 mrem/hour) and a background of approximately 40 mr/hour with 120 mr/hour during venting. NISA confirmed presence of cesium-137 and iodine-131 in the vicinity of the site. .

TEPCO is coordinating with Japanese authorities on how to cool down water in the spent fuel pool.

Unit 2 . . .

The reactor is shut down and the Reactor Core Isolation Cooling System is injecting water.

Reactor water level is lower than normal, but above the top of active fuel and decreasing.

Working wi.th the Japanese national government, TEPCO is taking measures to lower the

~. pressure.in the reactor containment by venting.

DC Power is stable.

The status of core coverage is highly Lincertain.

Japanese officials have informed the public of the possibility of a hydrogen explosion as a result of the loss of cooling.

Unit3 .

The reactor-is shut down. No offsite power, no emergency diesel generators working.

TEPCO is working with the Japanese national government to reduce the pressure in the reactor containment. *Containment remains intact. *

TEPCO informed Japanese Cabinet that Unit 3 water injection stopped and water level decre~sed exposing fuel. Reactor water level decreased to -150 to -200 cm below the top of the core, but have since been raised above the top of active fuel.

- Efforts to restart the Reactor Core Isolation Cooling System (high pressure injection) failed at 1510 EST (March 12, 2011). Emergency Core Cooling System flow could not be confirmed. Core damage likely. ..

The national government has instructed evacuation. for those local residents within 20km radius of the site periphery in accordance with clause 1 of the Article 15 of the Radiation Disaster Measure declared.

Alternative methods to inject water into the core are being investigated.

Containment sprays used to lower pressure within the reactor containment have be.en

cancelled.

A reactor pressure vessel manual safety valve was opened to lower the reactor pressure.

The valve opening procedure ended at 1920 EST on March 12, 2011. This procedure was 3 of 5 OFFICIAL USc ONLY

Earthquake/Tsunami Status Update March 14, 2011 . 0600 EDT

immediately followed at 1925 EST (March 12, 2011) by injection of sea water and boric acid into the reactor core (uncertain of success). .

At approximately 0230 EDT:on March 14, 2011, NRC rec.eived information that Unit 3 has lost the ability to inject seawater into the reactor and containment.

The status of core coverage is highly uncertain.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor**

containment vessel.

At approximately 2200 EDT (March 13, 2011) there was a hydrogen explosion at Unit 3 that damaged the secondary containment.

Unit4.

The reactor is shut down ...

Sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit 5 The reactor.is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor

. containment vessel.

Unit6 The reactor is* shut-down.

- A sufficient level of r~actor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Fukushima Daini Japan~se national government instructed evacuation for local residents within a 10km radius of

. the site boundary. Radiation levels at the site boundary have notexceeded limits. As of 1510 EST (March 12, 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is

not complete. The Daini units have AC power, but have lost their ultimate heat sink.

Unit 1 The rea.ctor is shut down. .

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit 2

The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

-

TEPCO prepared to reduce pressure in the reactor containment vessel.

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Earthquake/Tsunami Status Update March 14, 2011 0600 EDT The reactor was in cold shutdown at 2215 EST on Match 11, 2011 Unit4 The reactor is. shut down. .

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

Onagawa At 2145 CET (March 13, 2011 ). IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels. '

NRC Evaluation of Radiation Measurements from the USS Ronald Reagan On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were apprqximately 0.6 nirem per t)our gamma with no measurable activity on the ~hip surfaces. The NRC had received an IAEA

report shpwing dose rates of 1. 00 mrem/hr up wind at the site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months .

earlier and press reports for the preyious day of pl~nt venting. Given the r:netrological conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20~24 hour time period, a plume with low dose rates from the venting is credible at this location.

NRC staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from Japanese officials during venting from Fukushima*oaiichi Units 1, ~. and 3. *

The Navy 5.entthe co,:itamination samples to a base in Japan to p~rform an isotopic analysis to determJne the actual radio-nuclides .. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US ?'h Fleet has repositioned its ships out of the downwind plume direction from the

Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aJrcraft operating in the area.

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Earthquake/Ts1:1nami Status Update March 14, 2011 1330 EDT USNRC Emergency Operations Center Status Update March 14, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be dated and is subject to constant change.

Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC is coordinating with federal partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services; Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, Naval Reactors, and Secret Service.

The two senior experts supporting USAID response efforts from the NRC have arrived in Japan.

The experts have engaged with the US Ambassador's staff and have started coordinating transfer of information from Japanese authorities to the US government. At least six additional experts are ready to be deployed.

At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested US technical assistance with cooling the Fukushima Daiichi Units 1, 2, and 3, which have been without cooling for approximately 21 hours2.430556e-4 days 0.00583 hours 3.472222e-5 weeks 7.9905e-6 months . The effort is being coordinated by the

. US Ambassador.

The President considers it the highest priority to respond quickly and comprehensively to any request from Japan. USFJ is providing equipment to pump water at a,high pressure to assist TEPCO at its*Fukushima nuclear plant.

NRC is also coordinating with the lnternatjonal Atomic Energy Agency.

Q & A'.s have been developed and shared with Regional State Liaison Officers to dialogue with State counterparts.

NRC has issued 5 press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

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Earthquake/fsunami Status Update March 14, 2011 1330 EDT Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects.

Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the lnternatio.nal Atomic Energy Agency (IAEA)).

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, 6 at Fukushima Daiichi, 4 at Fukushima Daini, and 1 at Takai)

. Current Understanding of JapaneseJleactor Status . * * . *

(This information is compiled from TEPCO press releases - March 121\ 9pm and 11 pm, March 131\ 2am, Barn, 9am,* Opm, 1pm, 2pm, 3pm, 8pm, and 9pm,

and IAEA. information releases) r Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place for residents who stayed behind.

The site is at a level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES).

A level 4 INES event can include or be characterized by:

Minor release of radioactive material unlikely to result in implementation of planned countermeasures other ttian local food controls.

At least one death from radiation. * .

Fuel melt or damage to fuel resulting in more than*o.1 % release of core inventory.

Release. of significant quantities of radioactive material within an installation with a high

probability of significant public exposure. ...

All available information indicates that releases from the .Fukushima site have been carried out to sea by the prevailing winds.

Units 1, 2, and 3: shutdown due to earthquake At approximately 2300, March 14, Japan, Unit 2 core was again un_covered.

Units 4, 5,.and 6: shutdown due to outage, prior to earthquake All Units: all AC power on-site lost. .

Unit 1 Partial core damage from exposed fuel.

As of 2200 on March 14, Japan time. sea water is being injected.

The reactor was described as "more stable."

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LUSE ONLY Earthquake{f sunamf Status Update.March 14, 2011 1330 EDT Containment described as "functional."

Hydrogen explosion.has damaged reactor building roof.

Unit2

Hydrogen explosion possibility has been mitigated because a part of the reactor building roof has been removed.

RCIC has failed.

Coolant was stopped for quite sorrie tinie so core damage is assumed. Core was most likely totally uncovered for some time.

As of 2200 on March 14, Japan time, sea water is being injected.

Unit 2 containment is described as "functioning."

Unit.3 Condition described as essentially the same as Unit 1.

As of 2200 on March 14, Japan time, sea water is being injected.

Hydrogen explosion has damaged reactor building roof.

Containment described as "functional.")

Unit 4 The reactor is shut down.

Sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

UnitS .

The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Unit6 The reactor is shut down, A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

Fukushima Daini Japanese national government instructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST (March 12, 2011 ), an estimated 30,000 people have been eyacuated. Full evacuation is not complete. The Daini units have AC power, but have lost their ultimate heat sink.

Unit 1 The reac;;tor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

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Earthquake/Tsunami Status Update March 14, 2011 . 1330.EDT Unit 2 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained. .

TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

-

TEPCO prepared to reduce pressure in the reactor containment vessel.

The reactor was in cold shutdown at 2215 EST on March 11., 2011

. Unit4 .

The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained .

. TEPCO prepared to reduce pressure in the reactor containment vessel.

Onagawa t

At 2145 CET (March 13, 2011 ), IAEA reported that Japaryese authorities had informed it that

. radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels.

NRC Evaluation of Radiation Measureme nts from the USS Ronald Reagan On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese c6a~t. Dose rates from the overhead "plume;, were approximately 0.6 mrem per hour gamma with no measurable activity on the shi~ surfaces. The NRC had received an IAEA

report showing dose rates of -100 mrem/hr Lip wind at the site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months earlier and press reports for the previous day of plant venting. Given the metrological conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with* low dose rates from the venting is credible at this location.

NRC staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from Japanese officials during venting from Fukushima Daiichi Units 1, 2, and 3.

The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determine the actual radio-nuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US 7th Fleet has repositioned its ships out.of the downwind plume direGtion from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area. *

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Earthquakeff sunami Status Update March 14, 2011 2200 EDT USNRC Emergency Operations Center Status Update March 14, 2011 Earthquake/ Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be da~ed and is subject to constant change.

Changes/Ad ditions from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

NRC is coordinating with federal partners, including the White House, Congress, Department of Defense, Department of Energy, Department of Health and Human Services, Department of Homeland Security, Department of State, Department of Transportation, Environmental Protection Agency, Federal Emergency Management Agency, Naval Reactors, and Secret Service. *

The two senior experts supporting USAID response efforts from the NRC have arrived in Japan.

The experts have engaged with the US Ambassador's staff and have started coordinating transfer of information from Japanese authorities to the US government. Nine additional experts are ready to be deployed. *

At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have

requested US technical assistance with cooling the Fukushima Daiichi Units 1, 2, and 3, which have been without cooling for approximately 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months . The effort is being coordinated by the US Ambassador.

The President considers it the highest priority to respond quickly and comprehensively to any request from Japan. USFJ is providing equipment to pump water at a high pressure to assist TEPCO at its Fukushima nuclear plant.

The NRC is evaluating the current plant status information, and based on the information provided to date some fuel damage has occurred. The NRC is monitoring the restoration of cooling water to prevent additional fuel damage. Current information indicates that the structure that contains the reactor vessel remains intact On March* 14, 2011, NRC performed preliminary analysis based on the information available from the Japanese authorities. The result indicated the protective measures implemented by the Japanese government. including evacuation, sheltering, and potassium iodide, are

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Earthquake/Tsunami Status Update March 14, 2011 2200 EDT consistent with the U.S. Protective Action Guidelines. The NRC does not expect the U.S. to experience any harmful levels of radioactivity.

NRC is also coordinating with the International Atomic Energy Agency.

Q & A's have been developed and shared with Regional State Liaison Officers to dialogue with State counterparts.

NRC has issued 5 press releases related to the earthquake and tsunami. These press *releases

can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting sho'uld any issues arise related to earthquake or tsunami effects.

Status of Japanese Facilities (This information is compiled from available sourbes, including press rele1:1ses by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)) .

.Bacl,{ground: . . .

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (3 at Onagawa, 6 at Fukushima Daiichi, 4 at Ful<ushima Dairii, and 1 at Tokai)

Curtent Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases and IAEA information releases.)

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place for residents who ~tayed behind.

The site is at a level 4 "Accident with Local Consequences" on the International Nuclear and*

Radiological Event Scale (INES):

A level 4 INES event cim include or be characterized by:

Minor release of radioactive material unlikely to result in implementation .of planned countermeasures other than local food controls.

At least one death from radiation. .

Fuel melt or damage to fuel resulting in more than 0.1% release of core inventory.

Release of significant quantities of radioactive material Within an installation with a high probability of significant public exposure.

All available information indicates that releases from the Fukushima site have been carried out to sea by the prevailing winds.

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Earthquake/Tsunami Stat.us Update March *14, 2011 2200 EDT*

Units 1, 2, and 3: shutdown due to earthquake At approximately 2300, March 14, Japan, Unit 2 core was again uncovered.

Units 4, 5, and 6: shutdown due to outage, prior to earthquake All Units: all AC power on-site lost.

Unit 1 Partial core damage from exposed fuel.

As of 2200 EDT on March 14, it is reported that sea water is being injected.

The reactor was described as "more stable."

Containment described as functional."

Hydrogen explosion has damaged reactor building roof.

Unit2 Hydrogen explosion possibility has been mitigated because a part of the reactor building roof has been removed .

.RCIC has failed.

Coolant was stopped for quite some time so core damage is assumed. Core was most likely totally uncovered for some time.

- As of 2200 EDT on March 14, it is reported that sea water is being injected.

Unit 2 containment is described as functioning."

Unit3 Condition described as essentially the same as Unit 1.

As of 2200 EDT on March 14, it is reported that sea water*is being injected.

Hydrogen explosion has damaged reactor building roof.

Containment described as functional."

Unit4 The reactor is shut down.

Sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

UnitS The reactor is shut down.

- A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not'believe that there is any reactor coolant leakage inside the reactor containment vessel..

Unit6 The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO does not believe that there is any reactor coolant leakage inside the reactor containment vessel.

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O~C~AL USE ONLY Earthquake/Tsunami Status Update March 14, 2011 2200 EDT Fukushima Daini Japanese national government instructed evacuation for local residents within a 1Okrn radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST (March 12, 2011), an estimated 30,000 people have been evacuated. Full evacuation is not complete. The Daini units have AC power, but have lost their ultimate heat sink.

Unit 1 The reactor Is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reac~or containment vessel.

Unit2 The reactor is shut down.

- A sufficient level of reactor coolant to ensure safety is maintained.

- TEPCO prepared to reduce pressure in the reactor containment vessel.

Unit3 The reactor is shut down. . .

- A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

- The reactor was in cold shutdown at 2215 EST on March 11, 2011 Unit4

- The reactor is shut down.

A sufficient level of reactor coolant to ensure safety is maintained.

TEPCO prepared to reduce pressure in the reactor containment vessel.

At 2145 CET (March 13, 2011), IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels.

NRC Evaluation of Radiation Measurements from the USS Ronald Reagan On the morning of March 13, 2011, Naval l~ea"ctors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem per hour gamma with no measurable activity on the ship surfaces. The NRC had* received an IAEA report showing dose rates of 100 mrem/hr up wind at the site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months earlier and press reports for the previous day of plant venting. Given the metrological conditions; wind speed of 3-5. mph and the calm 'Class D and E' weather stability for the 20-24 hour time at period, a plume with low dose rates from the venting is credible this location.

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Earthquake/Tsuna mi Status Update March 14, 2011 2200 EDT NRC staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements .received from Japanese officials during venting from Fukushima Daiichi Units 1, 2, arid 3.

The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determine the actual radio-nuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US 7th Fleet has repositioned its ships out of the downwind. plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area.

Reactor Safety Team Worst Case Analysis .

Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Based on our Knowledge of Current Plant Conditions In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the water continues to boil and recede toward the. core bottom, the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt. With the

continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering the lower plenum will then cause the lower plenum liquid to boil. If cooling water is added to the drywell to a level above the top elevation of the lower plenum. lower head failure can be prevented. With no cooling water added to the drywall, the lower head will fail by creep rupture allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell could also result in a containment failure. With cooling water added to the drywell, however, a

. containment venting capability is also needed to preclude failure from over-pressurization. A containment failure will result in a large radioactive release to the environment.

Please note that failure to add water to the core and drywell is a hypothetical worst case event that will result in containment failure and radioactive release to the environment.

~rotective Measures Team Worst Case Analysis Meteorological conditions are changing, at 2300 the wind is from the NNE. Radioactive material (Cs-137 & 1-131) has been detected at the Yokosuka Naval Base.

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' USE ONLY Earthquake/Tsunami Status_ Update March 15, 2011 0600 EDT lJSNRC Emergency Operations Center Status Update

. -_ March 15, 2011 _

Earthquake*/ Tsunami Status Upctate -

Compiled .by Executive Briefl1Jg i'eam

'Cauth>11 - 1'h!,s'.lnformati9Q m~y b~ da.te~ and is subject tQ con.stant change.

Chanees/Additions from previous updates are underlined lf ST-tRC Status At 0946 EST, March 11, 20-11, the NRC entered Monitoring Moc:fe and the agency continues to*

monitor the unfolding events in Japan. The Headquarters Operations 'Center is staffed.

The two ~enior experts supporti_ng LI.SAID tespons~ effqrts from the NRC are ii"! Japan and have engaged with the us Ambassador's staff. Nin.e c1dditi<>~_afex_perts c1te_in. t~~~~it to Japan.

At 0550 EDT, March 14, 2011, the NRC experts in. Japan reported that.the Japanese have

requested US tec_hnical assistance with co_o.ling the Fukushima Oaiichi Units 1,. 2, and 3. ihe effort is being coordinated by the us Ambassadot.

The NRC is evaluating the current plant st~tus inforrnatio.n, and based on 'the information pi:ovided tQ date some fuel damage has_ occurred. The NRC is monitoring the restoration of cooling water to prevent additio_rial fuel damage. C1.1rreht information indicates th~t the structure

'that cQntains the reactor vess_el r'ern$ins lnt;:ict.

On March 14, 2011, NRC.performed prelim1n~ry analysis based.onthe information avaUable from the Japanese authorities. The result indicated the protective measures implemented by the Japanese government, including ~vacuation; sheltering, and potassium iodide, c3re consistent with the U.S. Protective Action Guidelines. The NRC does not expect the U.S. to experi_ence any-harmful levels of radioactivity.. '

NRC is also coord\~ating With the International Ate>mic,i;nergy Agency .

.Q & A's have been developed and shared with Regional State Liaison Officen~ to dialogue with State counterparts.

NRC has issued 5 press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

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Earthquakeffsunaml Status l.Jpdate M~nch 15, *2011 0600EDT Status of Japc}.nese Fadlitif~s (Thi$ information is ~ompiled .from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)}.

Backgroupd: .

There are 14. operational Soiling Water Re,ctors (BWRs) proximal to the earthquake zone (6 at Fukushima Daiichi, 4 ~t Fukushima Daini, 3 at Onagawa, and' 1 at iokai}

'Current Un'<l~rsta.nding of JapaneseReao:orStatus _. .

(This information is c;:omplled from TE,PCO press releases and IAEA information releases.)

Fukushima Daiichi Japan~se national government instructed evacuation for local ,residents within a .20km radius of the site boundary and sheltering in place out to 30 km for residents who stayed behind. Kyodo new$ reports a no fly zone out to 30 km.

The site is at a level 4 "Accident with Local Consequences~ on the International Nuclear and Radiolpgical Event Scele (INl;S). . . .

A level 4 !NES f)Vent ~n incluqe.or b.e chaf~c:tetjzed by: .* . . .*

Minor rele;ase of n1dioE:1cttve material unlikely Jo* result in implementation of planned co~.mtermeasures other than local fooct controls, *

- At least one death from radiation.

- Fuel melt or damage to fuel .resulting in more th~n 0.. 1% rere.ase of core inventqry, Release of significant quantities of radioactive material Within an installation With a high probal?itify of significant p1..1blfo expo~1,Jre.

All available. information indicates that releases from the Fukushima s'ite*have l:>een carried out to sea by the prevailing winds.

Units 1, 2, and 3: shutdown due to earthquake

- At approximately 2300, March 14, Japan, Unit 2 core was again uncovered.

Units 4, 5, and .6: sht.itdpwri d1,1e to otJtage, prior to earthquake ,

All Units: all AC power on-site. lost. - . .

Operators*and otlier'personnel not directly involved in water injection.have been evacuated~ 40..,

to 50 persons have been Jett onsite mitigate accident . . . -. .. .. . - .. . . . . . *,', . ..-- .

.Unit 1 Core damage occurred due to insufficient cooHng water caused by loss of offsite power and onsite diesel generators following the tsunami' ... **. .. . . . " .. . .. . . . .,' . . .

- As of ~200 JST .(0900 EI;)Tfon Marctd4, itis re.ported that sec1 wc1~r is.Qeiog injeged.

Containment described as "functionc1L 11

Hydrogemexplosion from-overheated fuel-water reaction has damaged reactorbui,lding roof.

There is stable cote coolitiq * * * *

The spent fuel pool level is unknown 2 of s 0F£1CIAL USE ONLY *~

0FFIC1~LUSE ~LY Earthqueike/Tsunami- Status Update March 15, 2011 0~00 EDT Radiation levels uncertain at this time

Unft.2 .. . .. .. . . .

,. Core damage occurred due to insufficient co.oling water .caused by loss of offsite .power and onsite diesel generators following the tsunami .. .. .

RCIC has failed. .

HyGfr:ogen explosion from overheated fuel..water reaction damaged the reactor building A.s of2200 Jsi (0900 EDT) on March 1.4, it is reported th.at sea water is be,ing injecteQ.

core Cooling is NOT stable. .. .

There ar~ reports* ofa loud sound at Unit 2 in the vicinity of the suppression chamber ~

containment integrity is not assured. * * * * * * * . ** * * *

~ The following pressures have been reported-RPVis at0.612.MPaJ88.psiLDrywell is at 1o psi.. and the Suppression. Pool instrumentation is unreadable. *

SRV control problem 1s making pressure control difficultfor reactor vessel at Radiatiort levels uncertain* this tihi~

- The sp~nffueLpool level is unknown Uni(~ . .. . .. . . . . . .

Possible core damage due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following ttie tsunami '

As of 2200 J~T '(0900 EDT) on March.14,*it is*reported that sea water .is being injected.

Hydrogen* explosion from overheated.fuel-water reaction has damaged reactor building roof.

Containment ,described as "functional." * ***

bore cooling believed to be stable .

There is ho spent fuel. pool information Radiation levels uncertain at this-time Unit4 Fire in the spenUueLbuilding {Zirconium?) with IAEA reports thaUire was* put out at 2200 EDT. March 14 * . . . . .

- . There is a pbssible water loss from pool:

Radiation levels uncertain. af this time Unif5

... The reactor is stable.

there is no stjent fuel pool information

.\,Jnit,6 . _ .

The reactor is stable.

There is no spent fuel pool information*

'Fukushima Daini . . .

,japanese national government instructed evacuation ft;r local residents within a 1Ol<hi radius of the site bQundary. Radiation ievels at the site boundary have not exceeded limits. As of 1510 E:ST (March 12, 2011), an estimated 30,000 people have been evac1,,1ated. Fl.ill evacuation is not complete. Ttie Daini units. have AC power, and were .previously reported tp have lost their ultimate heat sink. *

3 of 5 OFFICIAi USE ONLY . ~

OFFICIAL USE oNCY EarthquakeltsurfamiStatus UpdateMarch 15, 2011 '0$00EDT

'Unit i-4

.All units have stable offsite 'power

- All units are reported to be in cold shutdown with stable water level Latest !EPCO reports do not mention an'( problem with the 1Jltimate heat sink 011agawa At 2l 4$ CET (March 13, 2Q 11J, JAE.A report:ed that J~panese authoritie$.h~d)nformed it that; raciiqactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to .

nonrtc!.ibackgrou11d Jevels.

Unit*l-3 All units are shutdown and stable

.. The fire in. the turbine building has been* extinguished NRC Evaluation ofRadiation Measureinerits'from the USS Ronald Reagan

. . . . . . . . . . ' . /

.On the morning ofrvlarch'13, 2011, Naval Reactors nptified the NRC that dosE:l rates w~re being m~asured from the flight deck ofthe uss *Re'agc:in that was ... 130 na~tical inUes offthe

Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem*per hour gamma with no measurable. activity cm the ship surfaces. The NRC had received an IAEA report showing dose r$tes of 100 rrirem/hr up wind at the *site boundary ,measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months earlier c:1nd press re.port$*for the previous day of plant venting. Given the metrological conditions; wind speed of 3"~. mphand the calm 'Class D and E' weather stability for the 20.:24 hour time

period, a plunie With low dose rates from the venting is credible ~t this location.

NRC staff believes. that Us Nii1va1 readings are not inccmsi'stent based on ~Ports and shine dose. m.easurem~nts received from J.apanese official~ during venting from Fukushima Daiichi Units 1, 2; an_d 3 ..

The Navy sent the contamination samples to a. base in Japan to .perform an isotopic analysis to determine the actual. radio.:nuclides. The principle radionuclides identified were iodine, cesium,

~n9te9hne.tium, cgn~istentwith a release from a riuclear're~ctot.

.The .US 7 111 Fleet has repositioned :its ships out of.the downwind piurne direction from ,the

Fukushima Daiichi Nuclear Power Plant after defecting ,low level. contamination in the air and on its aireraft operating '.in the area. '

Reactor Safety Team Worst Case Analysis ..

Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Based on our Knowledge of Current Plant Conditions 4 of 5

~LY

OFFIGIAl r ISE ONL'i Earthquake/Tsunami Status Update March 15, 2011 0600 EbT In this ~ypothetical event in which .no cooling water is added to the core, ttie water level in the

core Will c:Jecrease, exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the water continues to.boil arid recede toward the core bottom; the heat-up rate of the rods will increase *rapidly resulting in fuel cladding failure and melt* With the .

continued lack of cooling water, the melting rods will relocate *toward the bottom of the co.re and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering* the lower plenum will then cause tht? iower plenum liquid to boil. If cooling water is added to the dryWell to. a level above the top elevation..of the lower plenum, lower head failure can be.

prevented. With ho* cooUng water added to the drywell, the. lowe,r he:;id will fa)i by creep rupture allowing molten fuel to. enter the drywall.. Moreover, the absence of cooling. water to the drywall*

could also result in a containment failure. With cooling water added to the drywell, however, a

. containment venting capability is also needed to preclude failure from over-pressurization . A containmentfailure will result in a large radioactive release to the environment.

Pl~ase note that failure tQ add water to the core and drywell is a hypothetical worst case .event

that will r~sult in containment failure and radioactive release to the environment.

Protective Measures T~am Worst Ca~e .A_n~ly~i,s Metrolo'gical forecasts show a steady wind shift continuing counter clockwise over the next 6 to

12 hours; with wlnd direction blowing a plurne 6ffshore again earlVWednesday morning. local

Japan* .time.

Based on unconfirmed reports that Fukushima Daiichi Unit2 tiad lost vessel and dr;vwell

. pressure subsequent to what Was believed to 'be an explosion in:*the reactor building I the PMT ran RASCAL. offsite dose estimations for an x-vessel core failure with loss of containment.

Estimates Were ruh with no change in wind directi6n* (wind toward Tokyo) ahd With the predicted to wind sliift counterclockwise over the island and back out sea~ For the steady wind' direction .

scenario; P,M3s: f>1 Rem TEDE and >5-Rem co*E:) were exceeded ~t so miles: . For' ihe wind to stiiftscenaih *PAGs* w~re exceeded between 30 4:o miles. A.RASCAL run o[a Unit-4 SFP zirconium fire {with wind shift) showed PAGs exceeded at15.1T1Hes.

to l~fo~matio~ ca.ntinued be corifliding regarding plant conditions for Uiiit 2 .and ~11. units SFPs. .

A report from the Japan Ministry of Foreign Affairs, .over phone. stated thatthere were pressure readings in both the vessei and drvwell. 'and thatthe suppression pool 'instrumentation w~s '

In "below scale~. the same report. no confirmation fo~ ~he statu~ ofany SF~ could be provided.

5 of 5 OFFICIAL USE ONLY

Of FICIAL USE ~LY Earthquake/Tsunami Status Update March 15, 2011 0730 EDT USNRC Em_ergency Operations Center Status Update March 15, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be dated a11d is subject t:o constant change.

Changes /Additions from previous updates are underlined USNRC Status At 0946 EST, March 1-1, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed. .

The two senior experts supporting USAID response efforts from the NRC are in Japan and have engaged with the US Ambassador's staff.'Nine additional experts are in transit to Japan.

At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested US technical assistance with cooling the Fukushima Daiichi Units 1, 2, and 3.

The effort is being coordinated by the US Ambassador.

The NRC is evaluating the current plant status information, and based on the information .

provided to date some fuel damage has occurred. The NRC is monitoring the restoration of cooling water to prevent additional fuel damage. Current information.indicates that the structwe that contains the reactor vessel remains intact.

On March 14, 2011, NRC performed preliminary analysis based on the information available

from the Japanese authorities. The result indicated the protective measures implemented by the Japanese government, including evacuation, sheltering, and potassium iodide, are consistent with the U.S. Protective Action Guidelines. The NRC does not expect the U.S. to experience any harmful levels ofradioactivity.

NRC is also coordinating with the International Atomic Energy A9ency.

Q & A's _have been developed and shared with Regional State Liaison Officers to dialogue with State counterparts.

NRC has issued 5 press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collectioris/news/2011/ *

' \

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Ol=Fle1"AL USE ONLY Earthquakeffsunami Status Update March 15, 2011 0730 EDT Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)}.

Background:

There are. 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (6 at Fukushima Daiichi, 4 at Fukushima Daini, 3 at Onagawa, and 1 at Tokai}

Current Understanding -~f Japanese Reactor Status

.(This information is compile9 from TEPCO press releases and IAEA information releases.)

Fukushima Daiichi

Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km for residents who stayed behind. Kyodo news reports a no fly zone out to 30 km.- *

The site is ata level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES}.

A level 4 INES event can include or be characterized by: .

Minor releas*e of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls.

At least one death from radiation.

Fuel nielt or damage to fuel resulting in more than Q.1% release of core inventory.

Release of significant quantities of radioactive material within an installation with a high probability of significant public exposure.

All available inf~rmation indicates that releases from the Fukushima site have been carried out to sea by the prevailing winds.

Units 1, 2, and 3: shutdown due to earthquake .

At approximately 2300, March 14, Japan, Unit 2 core was aQain uncovered.

Units 4, 5, and 6: shutdown due to outage, prior to earthquake All Units: all AC power on-site lost * *

Operators and other personnel not directly involved in water injection have been evacuated. 40-50 persons have been left onsite to mitigate accident.

Unit 1 Core damage occurred due to insufficient cooling water caused by loss of offsite power arid onsite diesel generators following the t~unami As of 2200 JST (0900 EDT} on March 14, it is reported that sea water is being injected.

Containment described as "functional." . * .

- .Hydrogen explosion from overheated fuel-water reaction has damaged reactor building roof.

There is stable core cooling

The spent fuel pool level is unknown 2of 5 Of?FICIAL USe QNLY

OFFICIAL USE OML Y Earthquake/Tsunami Status Update March 15, 2011 0730 EDT Radiation levels uncertain at this time Unit2 Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami RCIC has failed.

Hydrogen explosion from overheated fuel-water reaction damaged the reactor building As of 2200 JST (0900 EDT) on March 14, it is* reported that sea water is being injected.

Core Cooling is NOT stable .

There are reports of a loud sound at Unit 2 in the vicinity of the suppression chamber -

while containment integrity is not assured, all indication is that containment is intact.

The following pressures have been reported - RPV is *at 1.0 MPa (145 psi}.

SRV control problem is making pressure control difficult for reactor vessel Radiation levels uncertain at this time

The spent fuel pool level is unknown Unit3 Core damage due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami

As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injected.

Hydrogen explosion from overheated fuel-water reaction has damaged reactor building roof.

Containment described as "functional."

Core cooling believed to be stable There is no spent fuel pool information Radiation levels uncertain at this time Unit4 Fire in the spent fuel building was a small generator lube oil fire. IAEA reports that fire was put out at 2200 EDT, March 14. . .

There is a possible water loss from the spent fuel pool and operators are having difficulty providing adequate cooling and water level to the pool:

There are reports of possible hydrogen burn from the spent fuel.

High radiation dose rates measur.ed between Units 3 and 4, source is suspected to be Unit 4 spent fuel pool. . . .

Radiation levels uncertain at this time Unit 5 The reactor is stable.

There is no spent fuel pool information Unit6 The reactor is stable.

There is no spent fuel pool information Fukushima Daini Japanese natic;mal government instructed evacuation for local residents within a 10km radius of the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST (March 12,* 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is 3 of 5 Oef lCIAL U8E QNLY L

OFFIClAL USE ONLY Earthquakerrsunami Status Update March 15, 2011 0730 EDT-not complete. The Daini units have AC power, and were previously reported to have lost their ultimate heat sink.

Unit 1-4 All units have stable offsite power All units are reported to be in cold shutdown with stable water level Latest TEPCO reports do not mention any problem with the ultimate heat sink OnaJjawa At 2145 CET (March 13, 20.11 ), IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to

normal background levels.

Unit 1-3 All units are shutdown and stable The fire in the turbine building has been extinguished NRC Evaluation of Radiation Measurements from the USS Ronald Reagan On the morning of March 13, 2011, Naval Reactors notified the NRG that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem per hour gamma with no measurable activity on the ship surfaces. The NRG had received an IAEA report showing dose rates of 100 mrem/hr up wind at the site boundary.measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months .

earlier and press reports for the previous day of plant venting. Given the metrological conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time

period, a plume with low dose rates from the venting is credible at this location.

NRG staff believes that US Naval readings are not inconsistent based on reports and shine

dose measurements received from Japanese officials during venting from Fukushima Daiichi Units 1, 2, .and G. *

The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determine the actual radio-nucUdes. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US 7th Fleet has repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination.in the air and on*

its aircraft operating in the area.

.4of 5 OFFICIAL USE uNlY

OFFICIAL USE ONLT""' .*

. Earthquakefrsunami Status Updat~ March 15, 2011 0730 EDT Reactor Safety Team Worst Case Analysis Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Based on our Knowledge of Current Plant Conditions * \_

In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the water continues to boil and recede toward the core bottom, the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt. With the continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering the lower plenum will theh cause the lower plenum liquid to boil. If cooling water is added to the drywell to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the drywall, the lower head will fail by creep rupture

allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell-could also result in a containment failure. With cooling water added to the drywell, however; a containment venting capability is also needed to preclude failure from over-pressurization. A containment failure will result in a large *radioactive release to the environment.

Please note that failure to add water to the core and* drywall is a hyp9thetical worst ~ase event that will result in containment failure and radioactive release to the environment.

Protective Measures Team Worst Case Analysis Meteorological foreca_sts show a steady wind shift continuing counter clockwise over the next 6 to 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , with wind direction blowing a plume offshore again early Wednesday morning, local Japan time.

Based on unconfirmed reports that Fukushima Daiichi Unit 2 had lost vessel and drywell pr~_ssure subsequent to what was believed to be an explosion in the reactor building, the PMT ran RASCAL offsite dose estimations for an.x-vessel core failure with loss of containment.

Estimates were run with no change in wind direction (wind toward Tokyo) and with the predicted wind shift counterclockwise over the island and back out to sea. For the steady wind direction scenario, PAGs (>1 Rem TEDE and >5 Rem COE) were exceeded at 50 miles. For the wind shift scenario, PAGs were exceeded between 30 to 40 miles. A RASCAL run of a Unit 4 SFP

zirconium fire (with wind shift) showed PAGs exceeded at 15 miles.

Information continued to be. conflicting regarding pl~nt conditions for Unit 2 and all units SFPs.

A report from the Japan Ministry of Foreign Affairs, over phone, stated that there were pressure readings in both the vessel and drywe_ll, and that the suppression pool instrumentation was "below scale". In the same report, no confirmation for the status of any SFP. could be provided.

?.O~- , ..

OFf!TCIAL OS'E ONLY

oFFTCIAL USE7 0NLY Earthquake/Tsunami Status Update March 15, 2011 1330 EDT Status of Japanese Facilities (This information is compiled from available sources,.

including press releases by the Tokyo Electric Power Company (TEPCO) and-information from the International Atomic Energy Agency (IAEA)). * . * . * .

IAEA reports that at 1331 UTC on March 15, 2011 a 6.1 magnitude earthquake occurred in eastern Honshu, approximately 100 km from the Hamaoka nuclear power plant. Operational units at the plant remain in safe status after the earthquake. *

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone.(6 at Fukushima Daiichi, 4 at Fukushima Daini, 3 atOnagawa, and 1 at Tokai)

Current Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases and IAEA information releases.).

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km for residents who stayed behind. IAEA confirms a no fly zone out to 30 km around the Fukushima Daiichi plant.

Japanese authorities classified the event at a Level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES) based on radioactive dose measurements at the site boundary exceeding limit values.

All available information indicates that the majority of .releases from the Fukushima site have been carried out to sea by the prevailing winds.

Units 1, 2, and 3: shutdown due to earthquake At approximately 2300, March 14, Japan, Unit 2 core was again uncovered.

Units 4, 5, and 6: shutdown due to outage, prior to earthquake All Units: all AC power on-site lost.

Operators and other personnel not directly involved in water injection have been evacuated. 40-50 persons have been left onsite to m_itigate accider:it. *

2 of 6 OFFICIAL USE OOLY

Or'"Fl61AL USE ONLY Earthquake/Tsunam_i Status Update March 15, 2011 1330 EDT The following data was provided by the IAEA at 0912 EDT on March 15, 2011:

Data for Daiichi Units 1, 2 and 3 (as of 02:42 UTC)

Parameter Unit Fukushima Daiichi

Uriit 1 Unit 2

Unit3 Rector Pressure 0.072 (A) 0.244{A)

Vessel Pressure MPa 0.315 0.185 (B) 0.244 (B)

Drywell Pressure KPa 315 155 415 Reactor Level mm -1700(A) -1800(A)

(above the top of +400(A) active fuel) -1700(9) -2300(8)

Suppression Pool oc No Data No Data No Data Temperature Suppression Pool Pressure KPa No Data D/S D/S Unitl Core damage occurred due to insufficie.nt cooling water caused by loss of offsite power and onsite diesel generators following the tsunami

As of 2200 JST (0900 EDT) on March 14, it is *reported that sea water is being injected.

Containment described as "functional." ,

Hydrogen explosion from overhel;ited fuel-water reaction has damaged reactor building roof.

There is stable core cooling The spent fuel pool level is unknown

-

At 2000 ECT (March 14, 20U) IAEA reported dose rates at the Daiichi main gate of 11.9 mSv/hr (1190 mrem/hour), subsequent monitoring at 0200 EDT (March 15, 2011) showed dose rates at the Daiichi main gate of 0.6 mSv/hr ( 60 mrem/hr).

Unit2 Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami

RCIC has failed.

Hydrogen explosion from overheated fuel-water reaction damaged the reactor building As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injected.

Core Cooling is NOT stable There are reports of a loud sound at Unit 2 in the vicinity of the suppression chamber-while containment integrity is not assured, all indication is that containment is intact.

Radiation levels uncertain at this time *

The spent fuel pool level is unknown Unit3 Core damage due to insufficient cooling water caused by loss_ of.offsite power and onsite 3 of 6 OFFICIAL USE O"'f.JLY

OEEICIAL USE ON~Y Earthquakeffsunami Status Update March 15, 2011 1330 EDT diesel generators following the tsu_nami

- As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injected.

Hydrogen explosion from overheated fuel-water reaction has damaged reactor building roof.

Containment described as "functional."

Core cooling believed to be stable

. There is no spent fuel pool information Radiation levels uncertain at this time Unit4

'" Fire in the spent fuel building was a small generator lube oil fire .. IAEA reports that fire was put out at 2200 EDT, March 14. .

- . There is a possible water loss from the spentfuel pool and operatqrs are having difficulty

providing adequate cooling and water level to the pool;

- There are _reports of possible hydrogen burn from the spent fuel.

High radiation dose rate.s measured between Units 3 and 4, source is suspected to be the partially uncovered Unit 4 spent fuel pool.

UnitS

- The reactor is stable.

There is no spent fuel pool information

Unit6 The reactor is stable.

There is no spent fuel pool information Fukushima Daini Japanese national government instructed evacuation for local residents within a 10km radius of

, the site boundary. Radiation levels at the site boundary have not exceeded limits. As of 1510 EST {March 12, 2011 ), an estimated 30,000 people have been evacuated. Full evacuation is not complete. The Daini units have AC poV¥er, and were previously reported to tiave lost their ultimate heat sink.

Unit 1-4 All units have stable offsite power All units are reported to be in cold' shutdown with stable water level Latest TEPCO reports do not me~tion any problem with the ultimate heat sink Onagawa - .)

I At 2145 CET (March 13, 2011 ), IAEA reported that Japanes~ authorities had informed it that*

radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels .

. Unit 1-3

All units are shutdown and stable The fire in the turbine building has been extinguished 4of6 OFFICIAL USE Or-.tl.Y

O~LY Earthquakeffsunanii Status Update March 15, 2011 1330 EDT NRC Evaluation of Radi~tion Measurements from the USS Ronald Rea~an On the morning of March 1~. 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates. from the overhead "plume" were approx.imately 0.6 *mrem per hour gamma with no measurable.activity on* the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hr up wind at the site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months earlier and press reports for the previous day of plant venting. *Given the meteorological conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with low dose rates from .the venting is credible at this location.

NRC staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from Japanese officials during venting from Fukushima Daiichi Units* 1, 2, and 3. . .

I / * ' '

The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determin~ the actual radio-nuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US 7th Fleet has repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area.

Reactor Safety Team Worst Case Analysis Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Based on our Knowledge of Current Plant .Conditions .

In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the wate*r continues to boil and recede toward the core bottom, the heat-up rate of the rods will increas*e rapidly resulting in fuel cladding failure and melt With the continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the rea'ctor vessel. Molten fuel and core debris entering the lower plenum will then cause the lower plenum liquid to boil. If cooling water is. aqded to the drywall to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the.drywall, the lower head will fail by creep rupture allowing' molten fuel to enter the drywall. . Moreover, the absence of cooling water to the drywall

could also result in a containment failure. With cooling water added to the drywall, however, a

containment venting capability is also needed to preclude failure from over-pressurization. A*

containment failure will result in a large radioactive release to the environment.

Please note that failure to add water to the core and drywell is a hypothetical worst case event that will result in containment failure and radioactive release to the environment.

5 of6 OfEFICIAL USE UNLY

4 * * *

()H-'lclAL USE Of<JLY

Earthquake/Tsunami Status Update March 15, 2011 1330 EDT Protective Measures Team (PMT) Worst Case Analysis The PMT ran RASCAL offsite dose estimations for a hypothetical x-vessel core failure at Fukushima Daiichi Unit 2 with loss of containment. Two estimates were ruh, 1) no change in wind direction (wind toward Tokyo) and 2) with the predicted wind shift counterclockwise over the island*and back out to sea. For the steady wind direction scenario. PAGs {>1 Rem TEDE and >5 Rem COE) were exceeded at 50 miles beyond Unit 2. For the wind shift scenario, PAGs Were exceeded between- 30 to 40 miles.

Another RASCAL run for the Fukushima Unit 4 spen_t fuel pool (SFP) was updated to reflect an actual spent fuel inventory of 1331 bundles in the Unit 4 SFP. Since obse_rved meteorologi"cal data is unavailable, forecast meteorological data for the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months release period, which indicate

wind shifting offshore, were used. For the meteorological conditions utilized, at 20 miles, the Protective Action Guide (PAG) for Total Effective Dose Equivalent {TEDE) is 1.4 rem, slightly

. above the 1 rem PAG. At 30 miles, the TEDE is 0.9 rem.

(

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,.-OFFICIAL USE ONLY Earthquake/Tsunami Status Update March 15, 2011 *.1930 EDT USNRC Emergency Operations Center Status Update March 15, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution ~ This information may be dated and is subject to constant change.

Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to .

. monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

The two senior experts supporting USAID response efforts from the NRC are in Japan and have engaged with the US Ambassador's staff. Nine additional experts are in transit to Japan.

At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested US technical assistance with ceoling the Fukushima Daiichi Units 1, 2, and 3. The effort is being coordinated by the US Ambassador. At 0900 EDT (March 15, 2011 ), the Japanese government accepted DOE's Radiological Assistance Program (RAP) team assistance, which includes Aerial Measuring System (AMS). fly-overs.

The NRC is evaluating the current plant status information, and based on the information provided to date some fuel damage has occurred. The NRC is monitoring the. restoration of cooling water to prevent additional fuel damage. Current information indicates that the structures that contain the reactor vessels remain intact.

On March 14, 2011, NRC performed preliminary_ani;ilysis*based on the information available from the Japanese authorities. The result indicated the protective measures implemented by the Japanese government, including evacuation, sheltering, and potassium iodide, are not inconsistent with the U.S. Protective Action Guidelines. The NRC doe.s not expect the U.S. and its territories to experience any harmful levels of radioactivity.

NRC provided the White House .with information on protective measures for NRC staff in Japan, being able to provide advice for other federal workers in Japan, and that US citizens in Japan should follow advice of the government of Japan.

NRC is.also coordinating with the International Atomic Energy Agency.

Q & A's have been developed and shared with Regional State Liaison Officers to dialogue with State counterparts. .

NRC has issued* 6 press releases related to th~ earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

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Earthquake/Tsuna mi Status Update March 15, 2011 1930 EDT Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State

. facilities. NRC will resume this reporting should *any issues arise related to earthquake or tsunami effects.

The Institute of Nuclear Power Operations ONPO) issued a Level 1 Event Report (highest level) to its members this afternoon. It identifies 4 actions, with due dates, and requires a written response. In general, the actions include walkdowns and verifications of aspects of facility capabilities to address B.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation of station blackout (SBO) conditions; mitigation of internal and external flooding. and fire and flooding events that could be impacted by a concurrent seismic event.

Status of Japanese Facilities (Th.is information is compiled from available sou~ces, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)}.

IAEA reports that at 1331 UTC on March 15, 2011 a 6.1 magnitude earthquake occurred in eastern Honshu, approximately 100 km from t~.e Hamaoka nuclear power plant. Operational units at the plant remain in safe status after the earthquake.

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthqua~e zone (6 at Fukushima Daiichi, 4 at Fukushima Daini, 3 at Onagawa, and 1 at Tokai)

)

Current Understanding of Japanese Reactor Status (This information is compiled.from TEPCO press.releases and IAEA information releases.)

Fukushima Daiichi Japanese national government instructed evacuation for local. residents within a 20km radius of the site boundary ahd sheltering in place out to 30 km for residents who stayed behind. IAEA confirms a no fly zone out to 30 km around the Fukushima Daiichi plant. As of 1830 EDT on March 15. 2011, there have been no updates to protective actions:

Japanese authorities classified the event at a Level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES) based on radioactive dose measurements at the site boundary exceeding limit values.

All available information indicates that the majority of releases from the Fukushima* site have been carried out to sea by the prevailing winds. Forecast meteorological data for the 24 hour2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months period (until 1700 EDT on March 16, 2011) indicates wind remaining toward offshore (N. NW).

Units 1, 2, and 3: shutdown due. to earthquake At approximately 1o~o EDT (March 14, 2011), Unit 2 core was again uncovered.

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Earthquake/Tsunami Status Update March 15, 2011 1930 EDT Units 4, 5, and 6: shutdown due to outage, prior to earthquake All Units: all AC power on-site lost. * . .

Operators and other personnel not directly involved in water injection have been evacuated. 40-50 persons have been left onsite to mitigate accident.

The following data was provided by the IAEA at-0912 EDT on March 15, 2011:

Data for Daiichi Units 1, 2 and 3*<as of 02:42 UTC)

Parameter Unit FLJkushima Daiichi

/ . Unit 1 Unit2 *

Unit3 Rector Pressure 0.072(A) 0.244(A}

Vessel Pressure MPa 0.315 0.185 (8) 0.244(8)

Drywell Pressure KPa 315 155 415 Reactor Level mm -1700(A)

I

-1SOO(A)

(above the lop or +400(A) active fuel) -1700(8) -2300(8)

Suppression Pool *c.

Temperature No Data No Data No Data Suppression Pool Pressure KPa No Data D/S DIS Unit 1 * .. . .

Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami .

As of 2200 JST (0900 EDT} on March 14, it is reported that sea water is t,ei'ng injected. .

Containment described as "functional."

Hydrogen explosion from .overheated fuel-water reaction has damaged reactor building roof.

Sea water is being injected with reported stable cooling The spent fuel pool level is unknown

- High radiation levels reduced to 600 mSv/hour (60 mrem/hour} at 0200 EDT on March 15, 2011 at site gate. (Site gate is same for each unit}.

linit2 Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami Reactor Core Isolation Cooling (RCIC) has failed.

Hydrogen explosion from overheated fuel-water reaction damaged the reactor building Sea water injection restarted with reports of non-stable conditions. .

There are reports of a loud sound at Unit 2 in the vicinity of the suppression chamber. !!

was reported at 0730 EDT on March 15. 2011 that containment is intact (better than previously thought}.

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Earthquake/Tsunami Status Update March 15, 2011 1930 EDT High radiation levels reduced to 600 mSv/hour (60 mrem/hour} at 0200 EDT on March 15, 2011 at site gate: (Site gate is same for each unit).

The spent fuel po9l level is unknown Unit3 .

Core damage due to insufficient cooling water caused by loss of offsite power ahd onsite diesel generators following the tsunami Sea water is being injected with reported stable cooling Hydrogen explosion from overheated fuel-water reaction has damaged reactor building roof.

Primary containment described as functional."

There is no spent fue_l pool information High radiation levels reduced to 600 mSv/hour (60 mrem/hour) at 0200 EDT on March 15.

2011 at site gate. (Site gate is same for each unit).

Unit4 .

First fire in the reactor building was a small generator lube oil fire. IAEA reports that fire was put out at 2200 EDT, March 14.

High radiation levels reduced to 600 mSv/hour (60 mrem/hour) at 0200 EDT on March 15.

2011 at site gate. (Site gate is same for each unit).

Second fire began 1645 EDT. March 14. 2011 in reactor building. Reports indicate that this fire is not yet contained. TEPCO is determining whether to use helicopter or fire truck to fight fire. Fuel reported to be uncovered.

Radiation level in the area of unit 4 reported to be 30R/hour following second fire.

There is a possible water loss from the spent fuel pool and operators are having difficulty providing adequate cooling and water level to the pool. .

There are reports of possible hydrogen explosion due to uncovered fuel in the spent fuel .

pool (awaiting visual confirmation). .

High radiation dose rates measured betweel'1 Units 3 and 4, source is suspected to be the

.partially uncovered Unit 4 spent fuel pool.

UnitS The reactor is stable.

Spent fuel pool is reported to be heating up.

Unit6 The reactor is stable.

Spent fuel pool is reported to be heating up.

Fukushima Daini Japanese national government instructed evac.uatio~ for local residents within a 20km radius of the site boundary. As of 1510 EST (March 12, 2011), an estimated 30,000 people have been evacuated. Full evacuation is not complete. As of 1830 EDT *on March 15. 2011. there have not been updates to this information. The-Oaini units have AC power, and were previously reported to have lost their ultimate heat sink.

Unit 1-4

All units have stable offsite power All units are reported to be in cold shutdown with stable water level

-OfuFIGIAL USE ONCY Earthquake/fsunami Status Update March 15, 2011 1930 EDT Latest TEPCO reports do not mention any problem with the ultimate. heat sink Onagawa At 2145 GET (March 13, 2011 ), IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels.

Unit 1-3 All units are shutdown and stable The fire in the turbine building has been extinguished NRC Evaluation of Radiation Measurements from the USS Ronald Reagan and USS George Washington

On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem per hour gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hr up wind at the site boundary measured - 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months earlier and press reports for the previous day of plant venting. Given the meteorological

conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with low dose rates from the. venting is credibie at this location.

NRC staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from Japanese officials during venting from Fukushima Daiichi Units 1, 2, and 3.

The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to

determine the actual radio-nuclides. The prlr:iciple radlonuclldes identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The* US 71~ Fleet has repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area.

The US Naw identified radiological data from the USS George Washington located at Yokosuka Base at 0300 EDT on March 15, 2011 that showed an air sample of 7E-9 uCi/mL, from which a

the Naw estimated dose rate of 1.5 mrem/hour.

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Earthquake/Tsunami Status Update March 15, 2011 *

1930 EDT Reactor Safety Team Worst Case Analysis Hypothetical Worst Case Oaiichi Units 1, 2 and 3 Accident Sequence Based on our Knowledge of Current Plant Conditio_ns In this *hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the water continues to boil and recede toward the core bottom,.the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt. With the continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering the lower plenum will then cause the lower plenum liquid to boil. If cooling water is added to the drywell to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the drywell, the lower head will fail by creep rupture allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell could also result in a containment failure. With cooling water added to the drywell, however, a containment venting*capability is also needed to preclude failure from over-pressurization. A containment failure will result in a large radioactive release to the environment.

Please note that failure to add water to the core and dryWell is a hypothetical worst case event that will result in containment failure and radioactive release to the environment.

Protective Measures Team (PMT) Worst Case Analysis On March 15, 2011. the PMT ran RASCAL offsite dose estimations for a hypothetical. x-vessel core failure with loss of containment at a boiling water reactor (BWR) similar to Fukushima Daiichi Unit 2 with loss of containment. Two estimates were run: 1} no change in wind direction (wind towi;lrd Tokyo) and 2) with the predicted wind shift counterclockwise over the island and back out to sea. For the steady wind direction scenario, Protective Action Guides (PAGs} (>1 rem Total Effective Dose Equivalent (TEDE} and >5 rem Committed Dose Equivalent (CDE were exceeded at 50 miles beyond Unit 2. For the wind shift scenario, PAGs were exceeded between 30 to 40 miles. Another RASCAL run with assumptions to model the Fukushima. Unit 4 spent fuel pool (SFP) was updated to reflect a spent fuel inventory of 1331 bundles. Since observed meteorological data is unavailable, forecast meteorological data for the 24 hour release period, which indicate wind shifting offshore, were used. For the meteorological conditions utilized, at 20 miles, the PAG for TEDE is 1.4 rem, slightly above the 1 rem PAG. At 30 miles, the TEDE is 0.9 rem. As of 1900 EDT on March 15, 2011, we believe the runs are bounding for all four units. The PMT is working to update the RASCAL run for the Unit 4 spent fuel pool, usiriq actual meteorological parameters.

~ . ..

                                         ~ y Earthquake/f~unami S.tatus Update March 15, 2011 1930 EDT Reference Units 1 rem (rem)= 1000 millirem (mrein) 1.Sievert (Sv) = 1000 milliSieverts (mSv)
)

1 rem= 0.01 Sv = 10 mSv

Earthquakeffsunami Status Update Mar~h.16, 2011 0630 EDT USNRC Emergency Operations Center Status Update March 15, 2011 Earthquake / Tsunami Status Update Compiled by Executive.Briefing Team Caution - This information may be dated and is subject to constant change. Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed. A total of 11 NRC experts supporting USAID response efforts from the NRC are in Japan and have engaged with the US Ambassador's staff. At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested US technieal assistance with cooling the Fukushima Daiichi Units 1, 2, and 3. The effort is being coordinated by the US Ambassador. At 0900 EDT, March 15, 2011, the Japanese government accepted DOE's Radiological Assistance Program (RAP) team assistance, which includes Aerial Measuring System (AMS) fly-overs. NRC provided the White House with information on protective measures for NRC staff in Japan, being able to provide advice for other federal workers in Japan, and that U.s: citizens in Japan should follow advice of the government of Japan. NRC has issued numerous press rel.eases related to the earthquake and tsunami. These press releases can be found online at: http:/lwww.nrc.gov/reading-rm/doc-collections/news/2011/ Status of NRC Licensee and Agreement State Facilities . At this time, NRC is discontinuing reporting status of NRG licensee and Agreement State facilities. NRG will resume this reporting should any issues arise related to earthquake or . tsunami effects. The Institute of Nuclear Power Operations (INPO) issued a Level 1 Event Report (highest level) to its members this afternoon. It identifies 4 actions, with due dates, and requires a-written response. In general, the actions include walkdowns and verifications of aspects of facility capabilities to address B.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation of station blackout (SBO) conditions, mitigation of internal and external flooding, and fire and flooding events that could be impacted by a concurrent seismic event. 1 of 7 OFfi"ICIAL USE ONLY

OF<F"ICIAL USE ONLY'\ Earthquake/Tsunami Status Update March 16, 2011 0630 EDT Status of Japanese Facilities . (This information is compiled from available sources, including press. n~leases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)). IAEA reports that at 1331 UTC on March 15, 2011 a 6.1 magnitude earthquake occurred in eastern Honshu, approximately 100 km from the Hamaoka nuclear power plant. Operational units at the plant remain in safe status after th~ earthquake.

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (6 at Fukushima Daiichi, 4 at Fukushima ,Qaini, 3 at Onagawa, and 1 at Takai) Current- Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases and IAEA information releases.) Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km, for residents who stayed behind. As of March 12, a 10.km complete radius evacuation has been ordered for the public. IAEA confirms a no-fly zo.ne out to 30 km around the Fukushima Daiich_i plant. As of 1830 EDT on March 15, 2011, there have been no updates to protective actions. J~panese authorities classified the event at a Level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES} based on radioactive dose

measurements at the site boundary exceeding limit values.

IAEA reported at 1340 EDT, March 15, 2011: Highest reading at fence was 60 mrern/hour at 0200 EDT . Reduction of dose*rates after the peak at 2122 EDT, March 14 {400 mSv/hr in area surrounding Unit 3) 30 mSv/hr between Units 2 & 3, and 100 mSv/hr surrounding Unit 4 2227 EDT, March 15: dose info came in from DTRA. GIS will figure out locations. Offsite dose measured in Tokai on the coast 100 km NE of Tokyo on March 14 at 1845 EDT was 5 uSv/hr. On March 14, NISA reported 160 people were exposed to radiation around the Fukushima nuclear power plant. 170,000 people have been evacuated.

     - A no-fly zone was implemented 30 km from the site from zero to unlimited altitude.

Source from DOE NIT who talked with FM. On March 16, DITRA data is from 165 miles SSW from the site. All available information indicates that the majority of releases from the Fukushima site have been carried out to sea by the prevailing winds. Forecast meteorological data for the 24 hour period (until 1700 EDT o~ March 16, 2011) indicates wind remaining towar~ offshore (N, NW). Units 1, 2, and 3: shutdown due to earthquake *

     - At approximately 1000 EDT, March 14, 2011, Unit 2 core was again uncovered .
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OFFICIAL USE O~d~ Earthquake/Tsunami Status Update March 16, 2011 0630 EDT Units 4, 5, and 6: shutdown due to outage, prior tp earthquake* All Units: all AC power on-site lost. _ Operators and other personnel not qirectly involved in water injection have been

       *evacuated. 40-50 persons have been left onsite to mitigate accident.

Unit 1 Core damage occurred due to insufficient cooling water caused by loss -of offsite power and onsite diesel generators following the tsunami As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injected with reported stable cooling Containment described as "functional" . Hydrogen explosion from overheated fuel-water reaction has damaged reactor building (secondary containment)

The spent fuel pool level is decreasing .

High radiation levels reduced to 600 JJ.Sv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate. (Site gate is same for each unit.) Unit 2 . Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami

Reactor Core Isolation Cooling (RCIC) has failed Hydrogen explosion from overheated fuel-water reaction damaged the reactor building Secondary containment: Cut hole to reduce likelihood of hydrogen gas buildup s*ea water injection restarted with core cooling reported as not stable .

There are reports of a loud sound at Unit 2 in the vicinity of the suppression chamber. It

was reported at 0730 EDT on March 15, 2011 that containment is intact (better than previously thought). *

- High radiation levels reduced to 600 gSv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate. (Site gate is same for each unit.) T!ie spent fuel pool level is decreasing Unit3 Core damage due to insufficient cooling water caused by loss of offsite power and onsite-diesel generators fqllowing the tsunami Sea water is being injected with reported stable cooling Hydrogen explosion from overheated fuel-water reaction has damaged reactor building (secondary containment) .

 - Primary containment described as "functional" The spent fuel level is decreasing, with zirc interaction                              .

High radiation levels reduced to 600 gSv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate. (Site gate is same for each unit.) Unit4 First fire in the reactor building was a small generator lube oil fire. IAEA reports that fire was put out at 2200 EDT, March 14. .* High radiation levels reduced to 600 gSv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate. (Site gate is same for each unit.)

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Earthq~akefrsunam! Status Update March 16, 2011 0630 EDT Second fire began at 1645 EDT, March 15, 2011 in reactor building. Reports indicate ~hat this fire is not yet contained. TEPCO is determining whether to use helicopter or fire truck to fight fire. Fuel reported fo be uncovered. Radiation level inside Unit 4 reported to be 30R/hour followin*g second fire. High radiation dose rates mea.sured between Units 3 and 4, source is suspected to be the partially uncovered Unit 4 spent fuel pool. There is a total water loss from the spent fuel pool with* no ability to retain water in the pool: and zirc interaction taking place There are reports of possible hydrogen explosion due to uncovered fuel in the spent fuel pool (awaiting visual confirmation).. . Unconfirmed reports of 30 R/hr at the* Unit-4 SFP which is making fire fighting difficult (March 15). Another fire at Unit 4 SFP. Unit S'. The reactor is stable. . . Spent fuel pool is reported to be heating up. . IAEA reports that water level in was down 40 cm in 5 hour's since 0800 EDT, March 15, 2011. It is not clear if this. is the RPV or SFP water level .. TEPCO plans to use operational* diesel generator at Unit 6 to provide water to Unit 5. Unit6 The reactor is stc1ble. Spent fuel pool is reported to be heating up. Fukushima Daini . . . Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. As of 1510 EST, March 12, 2011, an estimated 30,000 people have been evacuated. Full evacuation is not complete. As of 1830 EDT on March 15, 2011, there have no.t been updates to this information. The Daini units have AC power, and were previously reported to have lost their ultimate heat sink. Unit 1-4

-   All units have stable offsite power
-   All units are reported to be in cold shutdown with stable water level Latest TEPCO reports do not mention any problem with the ultimate heat sink Onagawa At 2145 CET, March J3; 2011, IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear PoV,!er Plant have returned to normal background levels.

Unit 1-3 All units are shutdown and stable The fire in the turb_ine buildi11g has been extinguished 4 of 7 rn;:e1c141 11sE. QtJLv

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OFFICIAL USE ONLY . Earthquake/Tsunami Stc1tus Update March 16, 2011 . 0630 EDT

.NRC Evaluation ofRadiatio.n Measurements from the USS Ronald Reagan and USS .George Washington On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was '."'130 nautical miles off the           .

Japanese coast. Dose rates from the overhead "plume" we.re approximately 0.6 mrem/hour

gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hour up wind at the site boundary measured - 20 hours earlier. and press reports for the previous day of plant venting. Given the meteorological conditions; wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with low dose rate~ from the ve~ting is credible at this loca.tion.

NRC staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from Japanese officials during venting from Fukushima Daiichi Units 1,. 2, and 3. ' The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determine the actual radionuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor. The US 7th Fleet has repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area. The US Navy identified radiological data from the USS George Washington located at Yokosuka Base at 0300 EDT on March 15, 2011, that showed an air sample of 7E-9 uCi/mL, from which the Navy estimated a dose rate of 1.5 mrem/hour. Reactor Safety Team Worst Case Analysis Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Based 011 our Knowledge of Current Plant Conditions In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrees~. exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the water continues to boil and recede toward the core bottom, the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt. With the

continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering the.

lower plenum will then cause the lower plenum liquid to boil. If cooling water is added to the drywell to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the drywall, the lower head will fail by creep rupture allowing molten fuel to .enter the drywall. Moreover, the absence of cooling water to the drywell

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O~tAL USe 0~11 ~ V Earthquakeffsunami Status Update March 16, 2011 0630 EDT could also result in a containment failure. With cooling water added to the drywell, however, a containment venting capability is also needed to preclude failure from over-pressurizatiof"l. A containment failure will* result in a large radioactive release to the environment.
Please note that failure to add water to the core and drywell is a hypothetical worst case event
that will result in containment failure and radioactive release. to the environment.

Protective _Measures Team (PMT) Worst Case Analysis On March 15, 2011, the PMT ran RA~CAL offsite dose estimations for a hypothetical x-:yessel core failure With* loss of containment at a boiling water reactor (BWR) similar to Fukushima . Daiichi Unit 2 with loss of containment. Two estimates were run: 1) no change in wind direction (wind toward Tokyo) and 2) with the predicted wind shift counterclockwise over the island_ and back out to sea. For the steady wind direction scenario, Protective Action Guides (PAGs) (>1 rem Total Effective Dose Equivalent (TEDE) and >5 rem Committed Dose Equivalent (CDE)) were exceeded a*t 50 miles beyond Unit 2. For the wind shift scenario, PAGs were exceeded between 30 to 40 miles.

Another RASCAL run with assumptions to model the Fukushima Unit 4 spent fuel pool (SFP) was updated to reflect a spent fuel inventory of 1331 bundles. Since observed meteorologica_l .

data.is unavailable, forecast meteorological data for the 24 hour release period, which indicate wind shifting offshore, were used. For the meteorological conditions utilized, at 20 miles, the PAG for TEDE is 1.4 r~m. slightiy above the 1 rem PAG. At 30 miles, the TEDE is 0.9 r~m.

As of 1900 EDT on March.15, 2011, we believe the runs are.bounding for all four units. The PMT is working to update the RASCAL run for the Unit 4 spent fuel pool, using actual meteorological parameters. *

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EarthquakefTsunami Status Update March 16, 2011 0630 EDT Reference 1 rem (rem}= 1,000 millirem (mrem) 1 Sievert (Sv) = 1,000 milliSieverts (mSv} = 1,000,000 microsieverts (µSv}

1 rem= 0.01 Sv = 10 mSv 7 of7 OFFICIAL USE ONLY

l . Earthquake/Tsunami Status Update March 16, 2011

1400 EDT USNRC Emergency Operations Center Status Update

                                         .       March 15, 2011

Earthquake I Tsunami Status Update Compiled by Executive Briefing Team Caution - This Information may be dated and Is subject to constant change.
Changes/Additions from previous updates are underlined USNRC Status
At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitorthe unfolding events in Japan. The Headquarters Operations Center is staffed.

A total of 11 NRC experts supporting USAID respons~ effort~ from the NRC are in Japan and have engaged with the US Ambassador's st~ff. At0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have

requested US technical assistance with cooling the Fukushima Daiichi Units 1, 2, and 3. The
effort is being coordinated by the US Ambassador. At 0900 EDT, March 15, 2011, the Japanese government accepted DOE's Radiological Assistance Program (RAP) team assistance, .which includes Aerial Measuring System (AMS) fly-overs.
NRC provided the White House with information on protective measures for NRC staff in Japan, being able to provide advice for otherfederal workers in Japan, a.nd that U.S. citizens in Japan

  . should follow advice of the government of Japan.        *           **                          *
   *NRC has issued numerous press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc~gov/reading-rm/doc"'collections/newsi2011/

Status of NR(: Licensee and. Agreement State Facilities At thi!:i time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects. . . The Institute of Nuclear Power Operations (INPO) issued a Level 1 Event Report (highest level) to its members this afternoon. It identifies 4 actions, with due dates, and requires a written. response. In general, the *actions include walkdowns and verifications of aspects of facility capabilities to address 8.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation of station blackout (SBO) conditions, mitigation of internal and external flooding, and fire and flooding events that could be impacted by a concurrent seismic event. *

1of7 /

                                        ~EONLY

OF~ Earthquake/Tsunami Status Update March 16, 2011 1400 EDT Status of Japanese Facilities (This information is compiled from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)). IAEA reports that at 1331 UTC on March 15, 2011 a 6.1 magnitude earthquake occurred in eastern Honshu, approximately 100 km from the Hamaoka nuclear power plant. Operational units at the plant remain in safe status after the earthquake.

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (6 at Fukushima Daiichi, 4 at Fukushima Daini, 3 at Onagawa, and 1 at Takai)

Current Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases and IAEA information releases.)

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km for residen~s who stayed behind. As of March 12, a 1O km complete radius evacuation has been ordered for the public. IAEA confirms a no-fly zone out to 30 km around the Fukushima Daiichi plant. As of 1830 EDT on March 15, 2011, there have been no updates to protective actions. Japanese authorities classified the event at a Level 4 "Accidenrwith Local Consequences" on the International Nuclear and Radiological Event Scale (INES) based on radioactive dose measurements at the site boundary exceeding limit values. IAEA reported at 1340 EDT, March 15, 2011: Highest reading at fence was 60 .mrem/hour at 0200 EDT Reduction of dose rates after the peak at 2122 EDT, March 14 (400 mSv/hr in area surrounding Unit 3) 30 mSv/hr between Units 2 & 3, and 100 mSv/hr surrounding Unit 4 2227 EDT; March 15: dose info came in from DTRA. GIS will figure out locations. Offsite dose measured in Takai on the coast 100 km NE of Tokyo on March 14 at 1845 EDT was 5 uSv/hr. On March 14, NISA reported 160 people were exposed to radiation around the Fukushima nuclear power plant. 170,000 people have been evacuated. A no-fly zone was implemented 30 km from the site from zero to unlimited altitude. Source from DOE NIT who talked with FAA. On March 16, DITRA data is from 165 miles SSW from the ~ite,

All available information indicates that the majority of releases from the Fukushima site have been carried out to sea by the prevailing winds. Forecast meteorological data for the 24 hour period (until 1700 EDT on March 16, 2011) indicates wind remaining toward offshore* (N, NW). Units 1, 2, and 3: shutdown due to earthquake At approximately 1000 EDT, March 14, 2011, Unit 2 core was again uncovered. 2 of 7 * , ' 0-LY

Earthquakeffsunami Status Update March 16, 2011 1400 EDT Units 4, 5, and 6: shutdown due to outage, prior to earthquakeJ

        .A.II Units: all AC power on-.site lost.                                         .

Operators and other personnel not directly involved in water injection have been evacuated. *40-50 persons have been left onsite to mitigate accident. Unitl Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injected with

   . reported stable cooling Containment described as "functional"*

Hydrogen explosion from overheated fuel-water reaction has damaged reactor building . (secondary containment}

The spent fuel pool level is unknown High radiation levels reduced to 600 µSv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate. (Site gate is sarne for each unit.) .
Unit 2 Core damage occurred due* to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami Reactor Core Isolation Cooling (RCIC) has failed Hydrogen explosion from over.heated fuel-water reaction damaged the reactor building Secondary containment: Cut hole to reduce likelihood of hydrogen gas buildup*

Sea water injection restarted with core cooling reported as not stable There are reports of a loud sound at Unit 2 in the vicinity of the suppression chamber. It was reported at 0730 EDT on March 15, 2011 that containment is intact (better than previously thought). High radiation levels reduced to 600 µSv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate. (Site gate is same for each unit.) . The(spent fuel pool level is unknown. Possibility of steam/smoke from water boil-off or zirc-water reaction.

Unit3 Core damage due to insufficient cooling water caused by loss of offsite power and onsite
diesel generators following the tsunami Sea water is being injected with reported stable cooling Hydrogen explosion from overheated fuel-water reaction has damaged reactor building (secondary containment)

Primary containment described as functional" The spent fuel pool level is unknown. Possibility of.steam/smoke from water boil-off or zirc-water reaction. High. radiation levels reduced to 600 µSv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate .. (Site gate is same for each unit.) Uriit4

First fire in the reactor building was a small generator lube oil fire. IAEA reports that fire was put out at 2200 EDT, March 14.
3 of 7
Ol=FICIAL-OSE ONLY

Earthquake/Tsunami Status Update March 16, 2011 , 1400 EDT High radiation levels reduced to 600 µSv/hour (60 mrem/hour) at 0200 EDT on March 15,

      . 2011, at site gate. (Site gate is same for each unit.)

Second fire began at 1645 EDT, March 15, 2011 in reactor building.* Reports indicate that this fire is not yet contained .. Fuel reported to be uncovered.

Radiation level outside Unit 4 reported to be 30R/hour following second fire. .

High radiation dose rates measured between Units 3 and 4, source is suspected to be the partially uncovered Unit 4 spent fuel pool. The spent fuel pool's ability to retain water is in doubt. Explosion (likely hydrogen) in Unit 4 due to uncovered fuel in the spent fuel pool (awaiting visual confirmation).

Unit 5 The reactor is stable.

Spent fuel pool is reported to be heating up. IAEA reports that water level in was down 40 cm in 5 hours since 0800 EDT, March 15, 2011. It is not clear if this is the RPV or SFP water level. TEPCO plans to use operational diesel generator at Unit 6 to provide water to Unit 5. Unit6

The reactor is stable.

  - * . Spent fuel pool is reported to be heating up.

Fukushima Daini Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. As of 151 O EST, March 12, 2011, an estimated 30,000 people have been evacuated. Full evacuation is not complete. As of 1830 EDT on March 15, 2011, there have . not been updates to this information; The Daini units have AC power, and were previously reported to have lost their ultimate heat sinlc. Unit 1-4 All units have stable offs'ite power All units are reported to be in cold shutdown with stable water level Latest TEPCO reports do not mention any problem with the ultimate heat sink Onagawa At 2145 CET, March 13, 2011, IAEA reported that Japanese authorities had informed it that radioactivity levels at the *site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels. Unit 1-3 All units are shutdown and stable The fire in the turbine building has been extinguished 4of 7

                                         ~LY.

Of._.p"ICIAL USE ONLY Earthquake/Tsunami Status Update March 16, 2011 1400 EDT NRC Evalu~tion c;,f Radiation Measurements from the USS Ronald Reagan and USS George Was_hington On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan th.at was -130 nautical miles off the

Japanese coast. Dose rates from the.overhead "plume" were approximately 0.6 mrem/hour gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hour up wind* at the site boundary measured - 20 hours earlier and press reports for the previous day of plant venting. Given the meteorological conditions, wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a pll!me with low dose rates from the venting is credible at this location.

NRC staff believes. that US Naval readings are notiriconsistent based on reports l;lnd shine dose measurements received from Japanese officials during venting from Fukushima Oaiichi Units 1, 2, and 3. *

The Navy sent the contamination samples to a base in* Japan to perform an isotopic analysis to determine the actual radionuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US ~th Fleet has repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area.

The US Navy identified radiological data from the USS George Washington located at Yokosuka Base at 0300 EDT on March 15, 2011, that showed* an air ~ample of 7E-9 uCi/mL, from which the Navy estimated a dose rate of 1.5 mrem/hour.
Reactor Safety Team Worst Case Analysis.

Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Base_d on our Knowledge of Current Plant Conditions

In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environment and a sobseq~ent heat-up of the fuel rods. As the wat~r continues to boil and recede toward the core bottom, the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt. With the continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering the lower plenum will then cause the lower plenum liquid to boil. If cooling water is added to the drywell to a level above the top elevation of the lower plenum, lower head fai_lure can be.

prevented. With no cooling water added to the drywell, the lower head will fail .by creep rupture allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell 5 of 7 oi=i=r~t:*tffiE-of'JLY

Earthquake/Tsunami Status Update March 16, 2011 1400 EDT could also result in a containment failure. With cooling water added to the drywall, however, a containment venting capability is also needed to preclude failure from over-pressurization. A containment failure will result in a large radioactive release to the environment. Please note that failure to add water to the core and drywall is a hypothetical worst case event that will result in containment failure and radioactive release to the environment. Protective Measures Team (PMT) Worst Case Analysis A RASCAL run at 06:54AM (EDT} on March 16, 2011 for hypothetical combined core based on the following assumptions: Units 2 & 3 each, 33% core melt & no containment: Unit 4, full core offload 100% melt in the Spent Fuel Pool (SFP) with no roof; wind direction from West

Northwest blowing out to the ocean. Results: PAG exceded at 50 miles (80.5 km) with TEDE of 24.0 rem. and COE thyroid of 130 rem.

.' OFFICIAL USE ONLY Earthquake/Tsunami Status Update March 16, 2011 1400 EDT Reference Units 1 rem (rem)= 1,000 millirem (mrem)

1 Sievert (Sv) =1,000 milliSieverts (mSv) = 1,000,000 microsieverts (µSv}

-1 rem=:= 0.01 Sv = 10 mSv 7 of 7 o~IAL.U.S£.GMCY

OF~Y. Earthquake/Tsunami Status Update March 16, 2011 1900 EDT USNRC Emergency Operations Center Status Update March 16, 2011 Earthquake / Tsunami Status Update

                                  *compiled by Executive Briefing Team Caution - This information may be dated and is subject to constant change.

Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed. A total of 11 NRC experts supporting USAID response efforts from the NRC are in Japan and have engaged with the US Ambassador's staff.

At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested US technical assistance with cooling the Fukushima Daii~hi Units 1, 2, and 3. The effort is being coordinated by the US Ambassador. At 0900 EDT, March 15, 2011, t~e Japanese government accepted DOE's Radiological Assistance Program (RAP) team assistance, which inclu.des Aerial Measuring System (AMS) fly-overs.

NRC provided the White House with information on protective measures for NRC staff in Japan and information to provide advice for other federal workers in Japan. The current protective action recommendation for-U.S. citizens residing within 50 miles (80 km} of the Fukushima Daiichi site is to evacuate. NRC has issued numerous press releases related to the earthquake and tsunami. These press

*rele<!ises can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

Statu*s of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects.

The Institute of Nuclear Power Operations (INPO) issued a Level 1 Event Report (highest level) to its members on the afternoon of March 15, 2011. It identifies 4 actions, with due dates, and requires a written response. In general, the actions include walkdowns and verifications of aspects of facility capabilities to address B.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation *of station blackout (SBO) conditions,' mitigation of internal and external flooding, and fire and flooding events that could be impacted by a .

concurrent seismic event. *

                                             . 1of7----

0f:~ICllrt:'11sEONLY

                                        ~LY Earthquakefrsunami Status Update           March 16, 2011                               1900 EDT The Nuclear Energy Institute {NEI) issued two fact sheets on March 16, 2011: "Industry Taking Action to Ensure Continued Safety at U.S. Nuclear Energy Plants" and "Used Nuclear Fuel .

Storage at the Fukushima Daiichi Nuclear Power Plant."
Status of Japanese Facilities (This information is compiled froin available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)).

IAEA reports that at 1331 UTC on March 15, 2011 a 6.1 magnitude earthquake occurred in

eastern Honshu, approximately *100 km from the Hamaoka nuclear power plant. Operational units at the plant remain in safe status after the earthquake.

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (6 at Fukushima Daiichi, 4 atFukushima Daini, a:at Onagawa, and 1 at Tokai) Current Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases and IAEA information releases.) Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km for residents who stayed behind. As of March 12, a 1O km complete radius evacuatiQn has been ordered for the public,

IAEA confirms a no-fly zone out to 30 km around the Fukushima Daiichi plant As of 1830 EDT on March 15, 2011, there have been no updates to protective actions.
Japanese authorities classified the event at a Level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES) based on radioactive dose measurements at the site boundary exceeding limit values.
IAEA reported at 1340 EDT, March 15, 2011:
Highest reading at fence was 60 mrem/hour at 0200 EDT

Reduction of dose rates after the peak at 2122* EDT, March 14 (400 mSv/hr in area surrounding Unit 3)
30 mSv/hr between Units 2 & 3, and 100 mSv/hr surrounding Unit 4
2227 EDT, March 15: dose info came in from DTRA GIS will figure out locations. *
Offsite dose measured in Tokai on the coast 100 km NE of Tokyo on March 14*at 1845 EDT was 5 uSv/hr.
On March 14, NISA reported 160 people were exposed to radiation around the Fukushima nuclear.power plant. 170,000 people have been evacuated.
A no-fly zone was implemented 30 km from the site from zero to unlimited altitude.

Source from DOE NIT who talked with FAA.*

On March 16, *DTRA data is from 165 miles SSW from the site.

2 of 7 OFFlelAL USE ONLY

./

OFF!CIAL 1_isli ~

Earthquakeffsunami. Status Update March 16, 2011
1900 EOT All available information indicates that the majority of releases from the Fukushima site have*

been carried out to sea by the prevailing winds. Forecast meteorological data for the 24 hour period (until 1200 EDT on March 17, 2011) Indicates wind remaining toward offshore (N, NW). Units 1, 2, and 3: shutdown i;lue to earthquake

At approximately 1000 EDT, March 14, 2011, Unit 2*core was again uncovered.

Units 4, 5, and 6: shutdown due to outage, prior to earthquake

All Units: all AC power on-site lost.
Operators and other personnel not directly involved in water injection have been evacuated. 40-50 persons have been left onsite to mitigate accide_nt.

Unit1

Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite di~sel generators following the tsunami
As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injected with reported stable cooling
Containment described as "functional"
Hydrogen explosion from overheated fuel-water reaction has damaged reactor building (secondary, containment)
The spent fuel pool level is unknown
High radiation levels reduced to 600 µSv/hour (60 mrem/hour) at 0200 EDT on *March 15, 2011, at site gate. (Site gate is same for each unit.)
Unit2
Core damage occurred due to insufficient cooling water caused by loss of offsite. power
and onsite diesel generators following the tsunami
Reactor Core Isolation Cooling (RCIC) has failed
Hydrogen explosion from overheated fuel-water reaction damaged the reactor building
Secondary containmert: Cut hole to reduce likelihood of hydrogen gas bµildup *
Sea water injection restarted with core cooling reported as not stable * .
Primary containment is intact. '
High radiation levels reduced to 600 µSv/hour (60 mrem/hour) at 0200 EDT on March 15, 2011, at site gate. (Site gate is same for each unit.)
The spent fuel pool level is unknown.*Some water is available 'as evidenced by steam emanating from hole.
Unit3
Core damage due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami *
Sea water is being injected with reported stable cooling
Hydrogen explosion from overheated fuel-water reaction has damaged reactor building (secondary containment)
Primary containment described as "functional"
The spent fuel pool level is possibly drained -- some evidence of steam.
High radiation levels reduced to 600 µSv/hour (60 rrirem/hour) at 0200 EDT on March 15, 2011, at site gate. *(Site g~te is same for each unit.)

3 of 7

                                      @EFIChAtt'"OS_.:....E_O_N_LY

GFFICIAL USE: ONLY Earthquake/Tsunami Status Update March 16, 2011 1900 EDT Un.it4

First fire in the reactor building was a small generator lube oil fire. IAEA repprts that fire
was put out at 2200 EDT, March 14.
High radiation levels "reduced to 600 *µSv/hour (60 mrem/hour) at 0200 EDT on March t5, 2011, at site gate. (Site gate is same for each unit.) * * *
Second fire began at 1645 EDT, March 15, 2011 in reactor building. Reports indic~te that this fire is not yet contain_ed. Fuel reported to be uncovered.

Radiation level outside Unit 4 reported to be 30R/hour following second fire.
High radiation *dose rates measured between Units 3. and 4, source is suspected to be the partially uncovered Unit 4 spent fuel pool.
The spent fuel pool's ability to retain* water is in doubt, no steam - likely dry.

UnitS

The reactor is defueled.
Spent fuel pool is reported to be h~ating up.
NC power available from Unit 6 diesel generator.

Unit 6.

The reactor is defueled.
Spent fuel pool is reported. to be heating .up.
NC power available from diesel generator.

Fukushima Daini Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. As of.1510 EST, March 12, 2011, an estimated 30,000 people have been evacuated., Full evacuation is not complete. As of 1830 EDT *on March ~15, 2011, there have not been updates to this information. The Daini units have AC power, and were previously reported to have lost their ultimate heat sink .. Unit 1-4

All units have stable offsite power

    * . All units are reported to be in cold shutdown with stable water level

Latest TEPCO reports do not mention any problem with the ultimate heat sink otiagawa At'2145 CET, March 13, 2011, IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary ofthe Onagawa Nuclear Power Plant have _returned to normal background levels.

Unit 1-3

All units are shutdown and stable.. )
The fire in the turbine buil_ding has been extinguished 4of7 ~

QFFICIAL U~ENLY

OFFICIAL USE ONLY Earthquakeffsunami Status Update March 16, 2011 1900 EDT NRC Evaluation of Radiation Measurements from the USS Ronald Reagan and USS George Was~ington On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem/hour gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hour up wind at the site boundary measured - 20 hours earlier and press reports for the previous day of plant venting. Given the meteorological conditions, wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with low dose rates from the venting is credible at this location. NRC staff believes that US Naval readings are not inconsistent basec;I on reports and shine dose measurements received from Japanese officials during venting from Fukushima Daiichi Units 1, 2, and 3. The Navy sent the contamination samples to a base.in Japan to perform an isotopic analysis to determine the actual radionuqlides. The principle radionuclides identified were iodine, cesium, . and technetium, consistent with a release from a nuclear reactor. The US 7th Fleet has.repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area. The US Navy identified radiological data from the USS George Washington located at Yokosuka . Ba!?e at 0300 EDT on March* 15, 2011, that showed* an air sample of 7E-9 µCi/ml, from which the Navy estimated-a dose rate of 1.5 mrem/hour. *

Reactor Safety Team Worst Case Analysis Hypothetical Worst Case Daiichi Units 1, 2. and 3 Accident Sequence Based on our Knowledge of Current Plant Conditions In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the water continues to boil and recede toward the core bottom, the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt. With the continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering the
lower plenum will then cause the lower plenum liquid to boil. If cooling water is added to the drywall to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the drywell, the lower head will fail by creep rupture allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell could also result in a containment failure. With cooling water added to the drywell, however, a containment venting capability is also needed to preclude failure from over-pressurization. A containment failure will result in a large radioactive release to the environment.

5 of 7

~ y

9Ff;ICI.O.L use ONLY Earthquake/rsunami Status Update March 16, 2011 1900 EDT a Please note that failure to add water to the core and drywell is hypothetical worst case event that will result in containment failure and radioactive release to the environment. Protective Measures Team (PMT) Worst Case Anairsis A RASCAL run at 0654 EDT on March 16, 2011 for hypothetical combined core based on the following assumptions: Units 2 & 3 each, 33% core melt-& no containment; Unit 4, full core offlo~d 100% melt in the Spent Fuel Pool (SFP) with no roof; wind direction from West

Northwest blowing out to the ocean. Results: PAG exceded at 50 miles (80.5 km) with TEDE of 24.0 rem, and COE thyroid of 130 rem. *

           . l 6 of 7. 1 OFFl01AL 0SE 0NLY

Earthquake/Tsunami Status Update March 16, 2011 1900 EDT Reference

Units 1 rem (rem)= 1,000 millirem (mrem)

I -1 Sievert (Sv) = 1,000 milliSieverts (mSv) = 1,000,000 microsieverts (µSv) 1 rem= 0.01 Sv = 10 mSv 7of 7 QEEIGIAL USE Qf)IJLY

Earthquakefrsunami Status Update March 17, 2011 0600 EDT USNRC Emergency Operations Center Status Update March 17, 2011 Earthquake/ Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be dated and is subject to constant change. Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered.Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed. A total of 11 NRC experts supporting USAID response efforts from the NRC are in Japan and have engaged with the US Ambassador's staff. At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested US technical assistance with cooling_ the Fukushima Daiichi Units 1, 2, and 3. The effort is being coordinated by the US Ambassador. At 0900 EDT, March 15, 2011, the Japanese government accepted DOE's Radiological Assistance Program (RAP) team assistance, which includes Aerial Measuring System (AMS) fly-overs.

NRC provided the White House with information on protective measures for NRC staff in Japan and information to provide advice for other federal workers in Japan. The current protective action recommendation for U.S. citizens residing within 50 miles (80 km) of the Fukushima Daiichi site is to evacuate.
The US State Department has approved voluntary authorized departure for US Government employees at the Embassy in Japan.

NRC has issued numerous press releases related to the earthquake and tsunami. These press releases can be found onlihe at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/ Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects. The Institute of Nuclear Power Operations (INPO) issued a Level 1 Event Report (highest level) to its members on the afternoon of March 15, 2011. It identifies 4 actions, with due dates, and requires a written response. In general, the actic;>ns include walkdowns and verifications of asp~cts of facility capabilities to address B.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation of station blackout (SBO) conditions, mitigation of

~ y

                                        'SFFICIAL USE"ONLY Earthquake/Tsunami Status Update           March 17, 2011                               0600 EDT internal and external flooding, and fire and flooding events that could be impacted by a concurrent seismic event.

The Nuclear Energy Institute (NEI) issued two fact sheets on March 16, 2011: "Industry Taking Action to Ensure Continued Safety at U.. S. Nuclear Energy Plants" and "Used Nuclear Fuel Storage at the Fukushima*Daiichi Nuclear Power Plant." Status of Japanese Facilities (This information is compiled from available sources, including press. releases by the Tokyo . Electric Power Company (TEPCO) and information from the International Atomic Energy

Agency (IAEA)).

IAEA reports that at 1331 UTC on March 15, 2011 a 6.1 magnitude earthquake occurred in eastern Honshu, approximately 100 km from the Hamaoka nuclear power plant. Operational units at the plant remain in safe status after the earthquake.

Background:

There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (6 at Fukushima Daiichi, 4 at Fukushima Daini, 3 at Onagawa, and 1 at Tokai) Current Understanding of Japanese Reactor Sta~s . {This information is compiled from TEPCO press releases and IAEA information releases.)

  .Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km for residents who stayed behind. As of March 12, a 1O km complete radius evacuation has been ordered for the public. IAEA confirms a no-fly zone out to 30 km around the Fukushima Da_iichi plant f::..s of 1830 EDT on March 15, 2011, the.re h?lve been no updates to protective acUons.            *

Japanese authorities classified the event at a Level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES) based on radioactive dose

.

measurements at the site boundary exceeding limit values.
Federation of Electric Power Companies of Japan (FEPC) reported at 1015 EST, March 16, 2011: . .
Dose rate at main gate (monitoring station 6) ranged from 150 mr/hr to 1000 mr/hr:
10 Rem/hr west of Unit 3 and 4 (assuming on roadway nex_t to reactor buildings)
30 Rem/hr between Units 2 and 3 *
40 Rem/hr between Units 3 and 4 NHK media report on March 17, 0100 EDT stated that helicopter crews dumping water on Unit 3 reactor buildfng reported dose rates at 375 R/hr at 300 ft. above the building.

2 of 7 OFFIOIAL .USe Q[)JbY

OfEIGIAI I !SE QNI >>"' Earthquake/Tsunami Status Update March 17, 2011 0600 EDT

Offsite dose me~sured in Tokai on the coast 100 km NEof Tokyo on March 14 at 1845 EDT was 5 uSv/hr.
On March 14, NISA reported 160 people were exposed to radiation around the Fukushima nuclear power plant. 170,000 people have been evacuated. .
A no-fly zone was implemented 30 km from the site from zero to unlimited altitude.

Source from DOE NIT who talked with FAA.

On March 16, DTRA data is from 165 miles SSW from the site.

All available information indicates that the majority of releases from.the Fukushima site have been carried out to sea by the prevailing winds. Forecast meteorological data for the 24 hour period (until 1200 EDT on March 17, 2011) indicates wind headed offshore (from NW). Units 1, 2, and 3: shutdown due to earthquake

At approximately 1000 EDT, March 14, 2011, Unit 2 core was again uncovered.

Units 4, 5, and 6: shutdown due to outage, prior to earthquake

Operators and other personnel not directly involved in water injection have been evacuated. 40-50 persons have been left onsite to mitigate accident.

     !It   Unit 5 diesel generator is providing power to cool Unit 5 and Unit 6 spent fuel pool.

TEPCO is working to restore site power and anticipates restoration to Units 2,5, and 6 today. and Units 1, 3, and 4*tomorrow. Five portable pumps have arrived at the Daiichi site and additional equipment to connect the pumps is being coordinated.

DOE Aerial Measurement Teams have completed fly-over of the Daiichi site. Awaiting resu!ts.

Unit 1 ,

Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following th~ tsunami
As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injec~ed with reported stable cooling.
Containment described* as "functional"
Hydrogen explosion from overheated fuel-water reaction has damaged reactor .building (secondary containment) * *
The spent fuel pool level is unknown
Radiation levels 150-1000 mrem/hour at 1000 EDT on March 16, 2011, at site gate.

(Site gate is same for each unit.)

Core cooling is via the core spray header.

Unit 2

Core damage occurred due to insufficient cooling water caused by loss of offsite power
and onsite diesel generators following the tsunami
Reactor Core Isolation Cooling (RCIC) has failed

Hydrogen explosion from overheated fuel-water reaction damaged the reactor building
Secondary contai.nment: Cut hole in the side of the reactor building superstructure to reduce likelihood of hydrogen gas buildup
Sea water injection restarted with core cooling reported as not stable

OFFICIAL USE ONLY EarthquakefTsunami Status Update March 17, 2011

0600 EDT
Primary containment is intact.
Radiation levels 150-1000 mrem/hour at 1000 EDT on March 16, 2011, at site gate.

(Site gate is same for each unit.) *

  * . The spent fuel pool level is unknown. Some water is available as evidenced by steam emanating from hole.

Unit3

Core damage due to insufficient-cooling water caused by loss of offsite power and onsite .

diesel generators following the tsuriami

Sea water is being injected with reported stable cooling
Hydrogen explosion from overheated fuel*water reaction has damaged reactor building (secondary* containment)
Primary containment described as "functipnal"
The spent fuel pool level is possibly drained - some evidence of steam.
Radiation levels 150-1000 mrem/hour at 1000 EDT on March 16, 2011, at site gate.

(Site gate is same for each unit.)

Unit 3 is currently TEPCO's priority (unclear whether reactor or spent fuel poof}
Water cannon should be onsite soon (as of 0400 EDT)

Unit4

   *    .Unit was in a refueling outage at the time ofthe event and core was off loaded to the spent .fuel pool                                    *

First fire in the reactor building was a smail generator lube oil fire. IAEA repc;>rts that fire was put out at 2200 EDT, March 14.
Radiation levels 150-1000 mrem/hour at 1000 EDT on March'16; 2011, at site gate.

(Site gate is same *for each unit.) * *

Second fire began at 1645 EDT, March 15, 2011 in reactor building. Reports indicate that this fire is not yet contained. Fuel reported to be uncovered.

Radiation level outside L1nit 4 reported to be 30R/hour following second fire. *
High radiation dose rates measured between Units 3 and 4, source is suspected to be the Unit 4 spent fuel pool.
The spent fuel pool's ability to retain water is in doubt, no steam - likely dry.

UnitS

The reactor is defueled.
IAEA Reports Temperature of pool at 64.5 degrees C at 1500 EDT, March 16, 2011.
Unit 5 diesel generator is providing power to cool Units 5 and 6 spent fuel pools.

Unit 6

The reactor is defueled. .
IAEA Reports Temperature of pool at 61.0 degrees Cat 1300 EDT, March 16, 2011.
Power to cool the Unit 6 spent fuel pool is being provided by the Unit 5 diesel generator.

Fukushima Daini . . . Japanese national government instructed evacuation for local residents within a 20krri radius of the site boundary. As of 1510 EST, March 12, 2011, an estimated 30,000 people have been evacuated. Full evacuation is not complete. As of 1830 EDT on March 15, 2011, there have not been updates to this information. The Daini units have AC power, and were previously reported to have lost their ultimate heat sink. 4 of 7 _

~y

-1:

OFFICIAL USE ONLY Earthquake/Tsunami Status Update - March* 17, 2011 * - 0600 EDT. Unit 1-4

All units have stable offsite power
All units are reported to be in cold shutdown with stable water level
Latest:TEPCO reports do not.mention any problem with the ultimate heat sink Onagawa _ _

At 2145 GET, March 13, 2011, IAEA reported that Japanese authorities had informed it that

radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels.

Unit 1~3

All units are shutdown and stable
The fire in the turbine building has been extinguished Rokkasho *'

Earthquake cut off power supply, but diesel generators were immediately connected. Some water spilled from spent fuel pool - liquid was drained and appropri_ately recovered in liquid waste treatment system. Power supplies are restored to commercial electricity. All units operating. NRC Evaluation of Radiation Measurements from the USS Ronald Reagan and USS George Washington On the morning of March 13, 2011, Naval Reactors notified the NRG that dose .rates were being measured from the flight deck of the USS Reagan that was .... 130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were approximat~ly 0.6 mrem/hour gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hour ~P wind at the site boundary measured - 20 hours earlier and press reports for the previous day of plant venting. Given the meteorological conditions, wind speed of 3-5_ mph and the calm 'Class D and E' weather stability for the 20-24 hou*r time period, a plume with low dose rates from the venting is credible at this location. NRC staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from Japanese officials during venting -from Fukushima Daiichi . Units 1, 2, and 3.

The Navy sent the contamin-ation samples to a base in Japan to perform an isotopic analysis to determine the actual radionuclides. The principle radionuclides identified were iodine, ces_iuni, and technetium, consistent_ with a release from a nuclear reactor.
The US 7th Fleet has repositioned its ships out of the downwind .plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in th~ area.

5 of 7

                                      -Qi;;;:FIGIAL USl'i! 0~Y I

                                       -0FrlC11\L    a~ ONLY        .

Earthquake/Tsuna mi Status Update March 17, 2011 0600 EDT The US Navy identified radiological data from the USS George Washington located at Yokosuka Base at 0300 EDT on March 15, 2011, that showed an air sample of 7E-9 µCi/ml, from which the Navy estimated a dose rate of 1.5 mrem/hour. Reactor Safety Team Worst Case Analysis Hypothetical Worst Case Daiichi Units 1, 2 and 3 AccidentSequence Based on our Knowledge of Current Plant Conditions In this hypothetical event in which no cooling water is added to the core, the water level in the core will de.crease, exposing the top of the core* to a steam environment and a subsequent heat-up ofthe fuel rods. As the water continues to boil and recede toward the core bottom, the heat-up rate of the rods will increase rapidly resulting in *fuel cladding failure and melt. With the** continued lack of cooling water, the melting rods.will relocate toward the bottom of the core and eventually into the lower plenum of the reactor v~ssel. Molten fuel and core debris entering the

lower pl~num will then cause the lower plenum liquid to boil. If cooling water is added to the drywell to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the drywell, the lower head will fail by creep rupture allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell could also result in a containme11t failure; With cooling water added to the drywell, however, a containment venting capability is also needed to preclude failure from over-pressurization. A containment failure will result in a large radioactive release to the environment.

Please note that failure to add water to the core and drywell is a hypothetical worst case event that will result in containment failure and radioactive release to the environment.

Protective Measures Team (PMT) Worst Case Analysis A RASCAL run at 0654 EDT on March 16, 2011 for hypothetical combined core based on the following assumptions: ,Units 2 & 3 each, 33% core melt & no containment; Unit 4, fuil core offload 100% melt in the'Spent Fuel Pool (SFP) with no roof; wind direction from West
Northwest blowing out to the ocean. Results: PAG exceeded at 50 miles (80.5 km) with TEDE of 24.0 rem, and_CDE thyroid of 130 rem.

NRC PMT discussion with DOE NIT and NARAC requested expedited AMS flyover data of deposition near site to provide better characterization of source term. Information is expected by approximately 5am EDT.

Wind shift over land not expected until Sunday.

6 of 7 OFFICIAL I l::l~E O~Y

OFFICIAL USE uNLY Earthquakerrsunami Status Update March 17; 2011 0600 EDT Reference Units 1 rem (rem)= 1,000 millirem (mrem) . 1 Sievert (Sv) = 1,000 milliSieverts (mSv) = 1,000,000 microsieverts (µSv) 1 rem= 0.01 Sv = 10 IT)Sv. 7 of 7 OFFICIAL USE ONe'i'

Earthquake/Tsunami Status Update Mmch 17, 2011 0700 EDT USNRC Emergency Operations Center Status Update March 17, 2011 Earthquake I Tsunami Status Update Compiled by Executive Briefing Team Caution - This information may be dated and Is subject to constant change. Changes/Additions from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed. A total of 11 NRC experts. supporting* USAID response efforts from the NRC are in Japan and have.engaged with the US Ambassador's staff. At 0550 EDT, March 14, 2011, the NRC experts In Japan reported that the Japanese have requested US technical assistance with cooling the Fukushima Daiichi Units 1, 2, and 3. The effort is being coordinated by the US Ambassador. At 0900 EDT, March 15, 2011, the Japanese government accepted DOE's Radiological Assistance Program (RAP) team assistance, which includes Aerial Measuring System (AMS) fly-overs. NRC provided the White House with infom1atiol'"! on protective measures for NRC staff in Japan and information to provide advice for other federal workers. in Japan. The current protective action recommendation for U.S. citizens residing within 50 miles (80 km) of the Fukushima Daiichi site is to evacuate.

The US State Department has approved voluntary authorized departure of family members at the U.S. Embassy in Tokyo. the U.S. Consulate in Nagoya and the Foreign Service Institute in Yokohama.
NRC has issued numerous press releases related to the earthquake and tsunami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

Status of NRC Licensee and Agreement State Facilities At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting should any issues arise related to earthquake or tsunami effects. The Institute of Nuclear Power Operations (INPO) issued a Level 1 Event Report (highest level) to its members on the afternoon of March 15, 2011. It identifies 4 actions, with due dates, and requires a written response. In general, the actions include walkdowns and verifications of aspects of facility capabilities to address 8.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation of station blackout (SBO) conditions, mitigation of 1 of7 QFFIGll<L USE ONLY

0 ~ Earthquake/Tsunami Status Update March 17, 2011 . 0700 EDT internal and external flooding, and fire and flooding events that could be impacted by a concurrent seismic event. *

The Nuclear Energy Institute (NEI) issued two fact sheets on March 16, 2011: "Industry Taking Action to Ensure Continued Safety at U.S. Nuclear Energy Plants" and "Used Nuclear Fuel Storage at the Fukushima Daiichi Nuclear Power Plant."

Status of Japanese Facilities (This information is compiled-from available sources, including press releases by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)). . IAEA reports that at 1331 UTC on March. 15, 2011 a 6.1 magnitude earthquake occurred in

 *eastern Honshu, approximately-100 km from the Hamaoka nuclear power plant Operational units at the plant remain in safe status after the earthquake.

Background:

There are 14 operational Bolling Water Reactors (BWRs) proximal to the earthquake zone (6 at . Fukushima Daiichi, 4 at Fukushima Daini, 3 at Onagawa, and 1 at Takai) *

Current Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases and IAEA information releases.)

Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to*30 km for residents who stayed behind. As of March_ 12, a 10 km complete radius evacuation has been ordered for the. public. IAEA confirms

.a no-fly zone out to 30 km around the Fukushima Daiichi plant. As of 1830 EDT on March 15, 2011, there have been no updates to protective actions.

Japanese authorities classified the event at a Level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES) based on radioactive dose measurements at the site boundary exceeding limit.values.

Federation of Electric Power Companies of Japan (FEPC) reported at 1O15 EST, March 16, 2011: . .
Dose rate at main gate (monitoring station 6) ranged from 150 mr/hr to 1000 mr/hr.
1O Rem/hr west of Unit 3 and 4 (assuming on roadway next fo reactor buildings)
30 Rem/hr between Units 2 and 3
40 Rem/hr between Units 3 and 4 NHK media report on March 17, 0100 EDT stated that helicopter crews dumping water on Unit 3 reactor building reported dose rates at 375 R/hr at 300 ft. above the building.

2of7

OFFICIAL USE ONLY

9f~USEONL~ Earthquakefrsunami Status Update March 17, 2011 0700 EDT

   ** Offsite dose measured in Tokai on the coast 100 km NE of Tokyo on March 14 at 1845 EDT was 5 uSv/hr.

On March 14, NISA reported 160 people were exposed to radiation around the Fukushima nuclear power plant. 170,000 people have been evacuated.
A no-fly zone was implemented 30 l<m from the site from zero to unlimited altitude.

Source from DOE NIT who talked with FAA.

On March 16, DTRA data is from 165 miles SSW from the site.

All available information indicates that the majority of releases from the Fukushima site have been carried out to sea by the prevailing winds. Forecast meteorological data for the 24 hour period (until 1200 EDT on March 17, 2011) indicates wind headed offshore (from NW). Units 1, 2, and 3: shutdown due to earthquake

At approximately 1000 EDT, March t4, 2011, Unit 2 core was again uncovered.

Units 4, 5, and 6: shutdown due to outage, prior to earthquake

Operators and other personnel not directly involved in water injection have been evacuated. 40-50 persons have b~en left onsite to mitigate accident.
Unit 5 diesel ge.nerator is providing power to coor Unit 5 and Unit 6 spent fuel pool.

TEPCO is Working to restore site power and anticipates restoration to Units 2.5, and 6 today and Units 1. 3, and 4 tomorrow. Five portable pumps have arrived at the Daiichi site and additional equipment to connect the pumps is being coordinated. ** DOE Aerial Measurement Teams have completed fly-over of the Daiichi site. Awaiting results. Unitl.

Core damage occurred due to insufficient cooling water caused by loss of offsite power and onslte diesel generators following the tsunami .
As of 2200 JST (0900 EDT) on March 14, it is reported that sea water is being injected with reported stable cooling *
Containment described as functional"
Hydrogen explosion from overheated fuel-water reaction has damaged reactor building (secondary containment)_
The spent fuel pool level is unknown
Radiation levels 150-1000 mrem/hour at 1000 EDT on March 16, 2011, at site gate.

(Site gate is same for each unit.} *

Core cooling is via the core spray header.

Unit2

Core damage occurred due to insufficient cooling water caused by loss of offsite power and onsite diesel generators following the tsunami *
Reactor Core Isolation Cooling (RC JC) has failed
Hydrogen explosion from overheated fuel-water reaction damaged _the reactor building

Secondary containment: Cut hole* in the side of the reactor building superstructure to reduce likelihood of hydrogen gas buildup *

    ** * *Sea water injection restarted with core cooling reported as not stable 3 of 7 OFFICI.OcL U8E ONtv-'

QliiJ;~SE ONLY Earthquakeffsunami Status Update March 17, 2011 0700 EDT

Primary containment is intact.
Radiation levels 150-1000 mrem/hour at 1000 EDT on March 16, 2011, at site gate.

(Site gate is same for each unit.) .

The spent fuel pool level is unknown. Some water is available as evidenced by steam emanating from hole. *
Unit3
Core dam.age d~e to insufficient cooling water caused by loss of offsite power and onsite .

diesel generators following the tsunami * *

Sea water is being injected with reported stable cooling
Hydrogen explosion from overheated fuel-water reaction has damaged reactor building

         . (secondary containment)                       .

Primary containment described as "functional"
The spent fuel pool level is p9ssibly drained-some evidence.of steam. .
Radiation levels 150-1 ooo mrem/hour at 1ODO EDT on March 16, 2011. at site gate.

{Site gate is same for each unit.}

Unit 3 is currently TEPCO's priority (unclear whether reactor or spent fuel pool)
Water cannon should be onsite soon {as of 0400 EDD
Unit4
Unit was in a refueling outage at the time of the event and core was off loaded to the
spent fuel pool
First fire in the reactor building was a small generator lube oil fire. IAEA reports that fire was put out at 2200 EDT, March 14. *.
Radiation levels 150-1000 *mrem/hour at 1000 EDT on March 16, 2011, at site gate.

(Site gate is same for each unit.) *

Second fire began at 1645 EDT, March 15, 2011 rn reactor building. Reports Indicate that this fire is not yet contained. Fuel reported to be uncovered.
_Radiation level outside Unit 4* reported to be 30R/hour following second fire. *
High radiation dose rates measured between Units 3 and 4, source is suspected to be the Unit 4 spent fuel pool.
The spent fuel pool's ability to retain water is in doubt, no steam - likely dry.

UnitS

The reactor is defueled. .
IAEA Reports Temperature of pool at 64.5 *degrees Cat *1500 EDT. March 16. 2011.
Unit 5 diesel generator is providing power to cool *Units 5 and 6 spent fuel pools.

Unit6

The reactor is defueled. . .

     *. IAEA Reports Temperature of pool at 61.0 degrees Cat 1300 EDT, March 16, 2011.

Power to cool the Unit 6 spent fuel pool is being provided by the Unit 5 diesel generator.
Fukushima Daini .

.Japanese national government instructed evacuation for local residents within* a 20km radius of the site boundary. As of 1510 EST, March 12, 2011, an estimated 30,000 people have been evacuated. Full evacuation is not complete. As of 1830 EDT on March 15, 201*1, there have not been updates to this infom,ation. The Daini units have AC power, and were previously

. reported to have lost their ultimate heat sink. 4of7 _OFFICIAi I !SE 0~16¥=-

Earthquake/Tsunami Status Update March 17, 2011 0700 EDT Unit 1-4 .

All units have stable offsite power
All uni~s are reported to be in cold shutdown with stable water level
Latest TEPCO reports do not mention any problem with the ultimate heat sink Onagawa At 2145 CET, March 13, 2011, IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels.

Unit 1-3

All units are shutdown and stable
The fire in th~ turbine building has been extinguished Rokk.asho Earthquake cut off power supply, but diesel generators were immediately connected. Some water spilled from spent fuel pool - liquid was drained and appropriately recovered in liquid waste treatment system. Power supplies are restored to commercial electricity. All units
operating.

NRC Evaluation of Radiation Measurements from the USS Ronald Reagan and USS George Washington On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured. from the flight deck o( the USS Reagan that was -130 nautical miles off the

Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem/hour gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hour up wind at the site boundary measured - 20 hours earlier and press reports for the previous day of plantventing. Given the meteorological conditions, wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with low dose rates from the venting is credible at this location.

NRC staff believes that US Naval readings are not inconsistent based on reports and shine . dose measur.ements received from Japanese officials during venting from Fukushima Daiichi Units 1, 2, and 3. The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to* determine the actual radionuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor.

The US 7th Fleet has repositioned its ships out of the downwind plume direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in the air and on its aircraft operating in the area.

5of7

,i

                                      .oF~Y Earthquakeffsunami Status Update          March 17, 2011                                  0700 EDT The US Navy identified radiological data from the.USS George Washington locat~ at Yokosuka Base at 0300 EDT .on March 15, 2011, that showed an air sample of 7E-9 µCi/ml, from which the Navy estimated a dose rate of 1.5 mrem/hour.

Reactor Safety Team Worst Case Analysis Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Based on our Knowledge of Current .Plant Conditions In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environment and a subsequent heat-up of the fuel rods. As the water continues to boil and recede toward the core bottom, the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt With the .

continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenurn of the reactor vessel. Molten fuel and core debris entering the. lower plenum will then cause the lower plenum liquid to boil. If cooling water.is added to the drywell to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the drywell, the lower head will fail by creep rupture allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell could also result in a containment failure; With cooling water added to the drywell, however, a containment venting capability is also needed to preclude *failure from c;,ver-pressurization. A containment failure will result in a large radioactive release to the environment. Please note that failure to add water to the core and drywell is a hypothetical worst case event that will result in containment failure and radioactive release to the environment. Protective Measures Team (PMT) Worst Case Analysis A RASCAL run at'0654 EDT on March 16, 2011 for hypothetical combined core based ori the

following assumptions: Units 2 & 3 each, 33% core melt & no containment; Unit 4, full core.

offload 100% melt in the Spent Fuel Pool (SFP) with no roof; wind direction from West Northwest blowing out to the ocean. Results: PAG exceeded at 50 miles (80.5 km) with TEDE of 24.0 rem, and COE thyroid of 130 rem.

NRC PMT discussion with DOE NIT and NARAC requested expedited AMS flyover data of*

deposition near site to provide better characterization of source term. Information is expected by approximately 5am EDT. Wind shift over land not expected until Sunday. 6of7 QpFIGIAL USE 8NLY

OfFICIAL US,f..0Nt.Y Ea"1hquake/Tsunami Status Update March 17, 2011 0700 EDT Reference Units 1 rem (rem) = 1,000 millirem (mrem)

1 Sievert (Sv) = 1,000 milliSieverts (mSv) = 1,000,000 microsieverts (µSv) 1 r'em = 0.01 Sv = 10 mSv I

7 of 7 OEEJCIAI USE ONLY

O_eEICIAb ld9E o~*tY

     . Earthquake!Tsunami Status Update                      March 17, 2011                     1700 EDT USNRC Emergency Operations Ceriter Status Update March 17, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team Caution - This Information may be dated and is subject to constant change.

Changes/Additions .from previous updates are underlined USNRC Status At 0946 EST, March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed.

A total of 11 NRC experts supporting USAID response efforts from the NRC are in Japan and have engaged with the US Ambassador's staff. At 0550 EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested U~ technical assistance with cooling the Fukushima Daiichi Units 1, 2, and 3. The effort is being coordinated by the US Ambassador. At 0900 EDT, March 15, 2011, the Japanese government accepted DOE's RaEfiological Assistance Program (RAP) team assistance, which includes Aerial Measuring System (AMS) fly-overs. NRC provided the White House with information on protective measures for NRC staff in Japan and information to provide advice for other federal workers in Japan. The current protective action recommendation for U.S. citizens residing within 50 miles (80 km} of the Fukushima Daiichi site is to evacuate. The US State Department has approved voluntary authorized departure of family members at the U.S. Embassy in Tokyo, the U.S. Consulate in Nagoya and the Foreign Service Institute in Yokohama . 1

       .   ,I,      *' *'.:   .  ,* , ... * :... ,   4, N~.C. ~Js;.is~ueq i:n,1rne.~qus pre~s *r~l~~~es related to the earthquake and ts~nami. These press releases can be found online at: http://www.nrc.gov/reading-rm/doc-collections/news/2011/

Status ofNRC Licensee and Agreement State Facilities . At this time, NRC is discontinuing reporting status of NRC licensee and Agreement State facilities .. NRC will resume this report,ng should any issues arise related to earthquake or tsunami effects. ' The Institute of Nuclear Power Operations (INPO} issued a Level 1*Event Report (highest level) '-- to its members on the afternoon of March 15, 2011. It identifies 4 actions, with due dates, and requires a written response; .. In general, the actions include walkdowns and verifications of 1 of 7 OJ;".FlelAL U8E 6NLY

OPf!IClAL USE ONLY Earthquakefrsunami Status Update fvlarch 17, 2011 1700 EDT aspects *of facility capabilities to address 8.5.b equipment and procedures, Severe Accident. Management Guidelines (SAMGs), mitigation of station blackout (SBO). conditions, mitigation of internal and external flooding, and fire and flooding events that could -be impacted by a

concurrent seismic event.

The Nt1clear Energy Institute {NEI) issued two fact sheets on March 16, 2011: "Industry Taking Action to Ensure Continued Safety at U.S. Nuclear Energy Plants" and "Used Nuclear Fuel Storage at the Fukushima Daiichi Nuclear Power Plant." Status of Japanese Facilities (This information is compiled from available sources, including press releases *by the Tokyo Electric Power Company (TEPCO) and information from the International Atomic Energy Agency (IAEA)). . /" IAEA reports that at 1331 UTC on March 15, 2011 a 6.1 magnitude earthquake occurred in eastern Honshu, approximately 100 km from the Hamaoka nuclear power plant. Operational units at the plant remain in safe status after the earthquake.

Background:

. There are 14 operational Boiling Water Reactors (BWRs) proximal to the earthquake zone (6 at Fukushima Daiichi, 4 at Fukushima Dainl, 3 at Onagawa, and 1 at Tokai) Current Understanding of Japanese Reactor Status (This information is compiled from TEPCO press releases and IAEA information releases.) Fukushima Daiichi Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km for residents who stayed behind. As of March 12, a 1Okm complete radius evacuation .has been ordered for the public. IAEA confirms a no-fly zone out to 30 km around the Fukushima Daiichi plant. As of 1830 EDT on March 15, to 2011, there have been ho updates protective. . actions. * . Japa*nese authorities classifif;!!d the event*at a Level 4 "Accident with Local Consequences" on the International Nuclear and Radiological Event Scale (INES) based on radioactive dose measurements at the site boun~ary exceeding limit values. Federation of Electric Power Companies of Japan (FEPC) reported at 1015 EST, March 16, 2011:

Dose rate at main gate (monitoring station 6) ranged from 15d mr/hr to .1000 mr/hr.
1o Rem/hr west of Unit 3 and 4 (assuming on roadway next to reactor buildings)
30 Rem/hr between Units 2 and 3
40 Rem/hr between Units 3 and 4 2 of7 OFFICIAL USE ONLY

GFFICIAL Us"E O""fiJLY EarthquakefTsunami Status Update March 17, 2011 1700 EDT NHK m~dia* report on March 17, 0100 EDT stated that helicopter crews dumping water on Unit 3 reactor building reported dose rates at 375 R/hr at 300 ft. above the building.

Offsite dose measured in Tokai on the coast 100 km NE of Tokyo on March 14 at 1845 EDT was 5 uSv/hr.

On March 14, NISA reported 160 people were exposed to radiation around the
Fukushima nuclear power plant. 170,000 people have been evacuated.

1

A no:-fly zone was implemented 30 km from the site from zero to unlimited altitude.

Source from DOE NIT who talked with FAA.

On March 16, DTRA data is from 165 miles SSW from-the site.

All available information indicates*that the majority of releases from the Fukushima site have been carried out to sea by the prevailing winds. Forecast meteorological data for the 24 hour period (until 1200 EDT on March 17, 2011) indicates wind headec;j offshore (from NW). Units 1, 2, and 3: shutdown due to earthquake

At approximately 1000 EDT, March 14, 2011, Unit 2 core was again uncovered.

Units 4, 5, and 6: shutdown due to outage, prior to earthquake

Operators and other personnel not directly invoived in water injection have been evacuated. 40-50 persons have been left onsite to mitigate accident.
Unit 5 diesel generator is providing power to cool Unit 5 and Unit 6 spent fuel pool.

TEPCO is working to restore site power and anticipates restoration to Units 2,5, and 6 today and Units 1, 3, and 4 tomorrow. *

Five portable pumps have arrived at the Daiichi site and additional equipment to connect the pumps is being coordinated .

 . DOE Aerial Measurement Teams have completed fly-over of the Daiichi site. bata was received and is being analyzed.

Pr.iorl.ty'** Unit' Core Status Damaged, fuel >1/2 covered, RCS depressurized (FEPC) Radiat.ion released. Sea water-injection sufficient to cool core. (WANO) Containment Primary Containment, some damage. ~econdary Containment 1 3 lost (visual). Spen.t Fuel Pool 514 Bundles in SFP (GEH) Low Level (JAIF), Dumping water with helicopter suspended (NRC staff in Japan 0420 EDT) Spent Fuel Pool ?Pool is dry? 1201 Bundles in SFP (GEH) Damage to fuel 2 4 rods suspected (JAIF) dumping water from helicopter suspended (Casto 0420 EDT) 3 2 Core Status damaged, fuel 2/3 covered, RCS depressurized (FEPC). Sea

OFFICIAL~LY Earthquake/Tsunami Status Update March 17, 2011 1700 EDT water inject enough to cool core (WANO) Containment. Primary Containment, some damage. Secondary Containment, Hole cut in side of Fuel Flo9r metal to reduce H2 buildup, steam coming from hole (visual}. Spent Fuel Pool 587 Bundles in SFP (GEH} No information on SFP status (JAIF}. J Core Status damaged, >1/2 fuel covered, RCS depressurized (FEPC} Sea water inject enough to cool core (WANO} 4 1 Containment Primary Containment functional (JAIF) Secondary Containment

                    *1ost (visual)

Spent Fuel Pool 292 Bundles in SFP (GEH) SFP Level unknown (JAIF). Shutdown since 1/3/11. Core in RPV. SFP 950 Bundles (GEH), Unit 6 EDG 5 5 providing power Shutdown since 8/14/10. Core in RPV. SFP 876 Bundles (GEH), Unit's 6 6 EDG available. Common Spent Fuel Pool: 6,000 spent fuel bundles (GEH) Located on land side of Unit 4 (visual) 7 N/A Electrical Power Restoration from*switchyard to Unit 2 480 v Pumps (first) in progress (Sources: FEPC :--- Federation of Electric Power Companies of Japan: GEH - General Electric

Hitachi; JAIF - Japan Atomic Industrial Forum: WANO - World Association of Nuclear Operators)

Fukushima Daini Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary. As of 1510 EST, March 12, 2011, an estimated 30,000 people have been evacuated. Full evacuation Is not complete. As of 1830 EDTon March 15, 2011, there have not been updates to this information. The Daini units have AC power, and were previously reported to have lost their ultimate heat sink. Unit 1-4 "*

All units have stable offsite* power
All units are reported to be in cold shutdown with stable water level
Latest TEPCO reports do not mention any problem with the ultimate heat sink Onagawa At 2145 CET, March 13, 2011, IAEA reported that Japanese authorities had informed it that radioactivity levels at the site boundary of the Onagawa Nuclear Power Plant have returned to normal background levels.
4 of 7 OFEICJAL. USE ONtv

                                                                              *.J Earthquake/Tsunami Status Update               March 17, 2011                             1700 EDT .

Unit 1-3

All units are shutdown and stable

          * . The fire in the t1.,1rbine building has been extinguished Rokkasho                                                       .

Earthquake cut off power supply, but diesel generators were immediately connected. Some water. spilled from spent fuel pool - liquid was drained and appropriately recovered in liquid waste treatment system. Power supplies are restored to commercial electricity. All units

operating.

NRC Evaluation of Radiation Measurements from the USS Ronald Reagan and USS Ge~rge Washington

On the morning of March 13, 2011, Naval Reactors notified the NRC that dose rates were being measured from the flight deck of the USS Reagan that was -130 nautical miles off the Japanese coast. Dose rates from the overhead "plume" were approximately 0.6 mrem/hour gamma with no measurable activity on the ship surfaces. The NRC had received an IAEA report showing dose rates of 100 mrem/hour up wind at the site boundary measured - 20 hours earlier and press reports for the previous day of plant venting. Given the meteorological conditions, wind speed of 3-5 mph and the calm 'Class D and E' weather stability for the 20-24 hour time period, a plume with low dose rates* from the venting is credible at this location.
NRG staff believes that US Naval readings are not inconsistent based on reports and shine dose measurements received from JapanEise officials during venting from Fukushima Daiichi Units 1, 2, and 3.

The Navy sent the contamination samples to a base in Japan to perform an isotopic analysis to determine the actual radionuclides. The principle radionuclides identified were iodine, cesium, and technetium, consistent with a release from a nuclear reactor. The US 7th Fleet has repositioned its ships *out of the downwind ph,1me direction from the Fukushima Daiichi Nuclear Power Plant after detecting low level contamination in th_e air and on its aircraft operating in the area. The US Navy identified radiological data from the USS George Washington located at Yokosuka Base at 0300 E;DT on March 15,. 2011, that showed an air sample of 7E-9 µCi/ml, from which the Navy estimated a-dose rr;ite .of 1.5 mrem/hour.

Reactor Safety Team Worst Case An~lysis Hypothetical Worst Case Daiichi Units 1, 2 and 3 Accident Sequence Based on our Knowledge of Current Plant Conditions 5 of7 OFFIGJAI I !SE QNI Y

                                          ~LY Earthquake rrsunami Status Update           March 17, 2011                                 1700 EDT In this hypothetical event in which no cooling water is added to the core, the water level in the core will decrease, exposing the top of the core to a steam environmen t and a subsequent heat-up of the.fuel rods. As the water continues to boil and recede toward the core bottom, the heat-up rate of the rods will increase rapidly resulting in fuel cladding failure and melt. With the continued lack of cooling water, the melting rods will relocate toward the bottom of the core and eventually into the lower plenum of the reactor vessel. Molten fuel and core debris entering the lower plenum will then cause the lower plenum liquid to boil. If cooling water is added to the drywell to a level above the top elevation of the lower plenum, lower head failure can be prevented. With no cooling water added to the drywell, the lower head will fail by creep rupture allowing molten fuel to enter the drywell. Moreover, the absence of cooling water to the drywell could also result in a containmen t failure. With cooling water added to the drywell, however, a containment venting capability.is also needed to preclude failure from over-pressurization. A containment failure will result in a large radioactive release to the environment.

Please note that failure to add water to the core and drywell is a hypothetical worst case event tnat will result in containmen t failure and radio.active release to the environment. Protective Measures Team (PMT) Worst Case Analysis A RASCAL run at 0654 EDT on March 16, 2011 for hypothetical combined core based on the following assumptions: Units 2 & 3 each, 33% core melt & no containment; Unit 4, full core offload 100% melt in the Spent Fuel Pool (SFP} with no roof; wind direction f(om West Northwest blowing out to the ocean. Results: PAG exceeded at 50 miles (80.5 km) with TEDE of 24.0 rem, and.COE thyroid of 130 rem. *

PMT has transmitted agreed source term to NARAC and is awaiting updated dose projections for along Japan and trans-Pacifi c for doses to US west coast. *First AMS run data received.

PMT working to correlate AMS' data with limited survey data from Japan. Wind shift over land not expected until Sunday. 6 of 7 OPFICI.A.l I ISF ~ ONLY L_

. ~ Q1!i=lciAL USE ONLY-EarthquakefTsunami Status Update March 17, 2011 1700 EDT Reference Units . 1 rem (rem) = 1,000 millirem (mrem) . 1 Sievert (Sv) = 1,000 milliSieverts (mSv) == 1,000,000 microsieverts (µSv)

         =           =

1 rem 0.01 Sv 1O mSv. 7 of7 OFFICIAL tJSE QN(Y

Earthquake/Ts unami Status Update March 18, 2011 0600 EDT

        .USN RC Emergenc y Operation s Center StatlJs -Update March 18, 2011 Earthquake / Tsunami Status Update Compiled by Executive Briefing Team This report was changed to include NRC's current understanding of the ongoing situation in Japan. Historical and background information can be found in past reports.

USN RC Status At 0946 ESi, .March 11, 2011, the NRC entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The Headquarters Operations Center is staffed @tt* A total of 11 NRC experts supporting USAID response efforts from the NRC are in.Japan and have engageq with the US Ambassador and his staff. At 0550 ,EDT, March 14, 2011, the NRC experts in Japan reported that the Japanese have requested lJS technical assistance wlth cooling the Fukushima Daiichi Units, ~~:Jn~ded. The effort ts being coordinated by the US Ambassador. At 0900 EDT, March 15, 2011, the Japanese government accepted DOE's Radiologic91Assistance Program (RAP) team assi$tance, which incluqes Aerial Measuring System (AMS) flyovers. §fi,)M,a"~ti:'.f6, NRC provided the White House with information on protective measures for NRC staff in Japan and information to*provide advice for otherfederal workers in Japan. The current protective action recommeridatio rf for U.S. *citizens residing within 50 miles (80 km) of the Fukushima Daiichi site is fo evacuate. The US Sfate Department has approved voluntary authorized departure of family members at the U.S. Erriba$sy in Tokyo, the U.S. Consulate in Nagoya and the Foreign Service Institute in Yokohama.

ITap~i;iesee:Minisjiybf:ti5~fense:ap@afs'.t,crl:;~fia~ing: on:i,~rge(role. ;,n?tt1.~fr~spgff~e ,effort:

NR.C ha$ is$ued numer9us press. releases related to the earthquake and tsunami. These .press* releases can be found online at: http://WW\v.nrc.gov/reading-nn/doc-collections/news/2011/ ifffl:ililit~1,~~i,tl1;krr:t~~~,,~~=i,t:i~ oftempbrarypump1ng::equ1p111erit,for/~m~rgencycool1ng. Bechtel'has complete(ifeng ineeritig\'deslgf r.work arid** is'working wittrventlqrs'tq ;prbcureittfe req'uit~;i:nai~ry~.1.\y~~[j p~~.,;n:~t:~~tf~~~p9*~¥,;~~YOJ~Dqa~;1h~~t:i:ai;tivlii~i>:f$~A~l1fochi'fu~y b~'tt:1¢{9rgan1zatr~n,.tfi;:it w1t1;rri~mlL1:1oa:p~~~~i~..the.:!:iqV!Pffi~nt 1 of 5 OFFICIAL USr! ONLY

OPF1CIAL USE 0"'1t f" EarthquakefTsunami Status Update

March 18, 2011 0600 EDT Status of NRC Licensee and Agreement State Facilities NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will resume this reporting.,.~,.t1~'<~~~~~~.~r.~~J!\.~t~d t? e~rthqu~k~.,.gr.:tsunami :~,~t~.:-.,#~~~$

    ~~gernei11_p,eGJmr:m1:1n,.!2~:!!gn:f.Q.~ <<tti]j._WJ~--Ji'mt~~£12.!i fl,E!e,t.                              *            *                              -       *       .

The Institute of Nuclear Power Operations (INPO) issued a Level 1 Event Report (highest level) to its members on the afternoon of March 15, 2011. It identifies 4 actions, with due dates, and requires a written response. In general, the actions include walkdowns and verifications of aspects of facility capabilities to address B.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation of station blackout (SBO) conditions, mitigation of internal and external flooding, and fire and flooding events that could be impacted by a concurrent seismic event.

The Nuclear Energy Institute (NEI) issued two fact sheets on March 16, 2011: "Industry Taking Action to Ensure Continued Safety at U.S. Nuclear Energy Plants". and "Used Nuclear Fuel Storage a_t the Fukushima Daiichi Nuclear Power Plant."

Current Understanding of Japanese Facilities

  ' (This Information is compiled from TEPCO press releases, IAEA information releases, Federalion of Electric Power Companies of Japan, Japan Atomic Industrial FQrum, World Association of Nuclear Operators, ltSffllf~Ji~u'ij'.tffltlaJt and others.)

I . . , *

Fukushima Daiichi . * .

Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km for res_idents who stayed behind. As of March 12, a 10 km complete radius evacuation has been ordered for the public. IAEA confirms a no-fly zone out to 30 km around the Fukushima Daiichi plant. As of 1830 EDT on March 15, '- 2011, there have been no updates to protective actions. .

GI .ssifica}I&l,Wf!ih~lilm@1[4UaR~

                                       ...;...:...... on the International Nuclear and Radiological Event Scale NHK media report on March 17, 0100 EDT stated that helicopter crews dumping water ori Unit 3 reactor building reported dose rates at 375 R/hr at 300 ft. above the building.

Gl<s~fojj~~,-~~ca:m5m"Gtit~~~rfdda*~%i~~r ()lii~l.~MQ---

DOE Aerial Measurement Teams have completed~ flyovers of the Daiichi site. Data f~fm~jfli~

m,'{Qird~llSJ] was received and is being analyzed. * . .

     -        : Hli!'l'f*' - ~ ~ u * ~ ..,...vt'~~~'m"l!!m'r>.'ti iJ:he~N~sa.L~ntwJ.~.!IDi~!!il.2.~eJ~..!*e.t:.a,i                   ,,,p~~~&s~~

2 of 5 OE.EICIAI I fSF PbllY

O~ONLY Earthquakerrs unami Status Update March 18, 2011 0600 EDT Nim

Fukushima Daiichi Priority STATUS as of 1500 EDT, March 17, 2011- (0400 Japan) Unit Core Status: damaged

Primary Containment: some damage Secondary Containment: lost (visual) 1 3 2 4 Core Cooling: RCS depressurized; sea water inject to cool core (Source: JAIF)

Primary Containment: pa'~titSTEl~to'?.~ Secondary Containment: hole cut in side offuel floor metal to reduce H2 buildup Spent Fuel Pool: 587_buridles in pool; ~'ir¢.@~~ J.mg 3 ~~iLViZ~mmte *-'-~~ * . 2 Core Status:~--*-'.!!.*. . -'* Core Cooling: RCS depressurized; sea water inject to cool core (Source: JAIF)

Primary Containment: functional Secondary Containment: lost (visual)

Spent Fuel Pool: 292 bundles in pool, water level unknown, fire

  .4     trucks are supplying seawater for cooling spray                  1 Shutdown since January 3, 2011 Core Status: core in RPV         (§.?:faR'~:e:of Spent Fuel Pool: 950 bundles; unit 6 emergency diesel generator s     available                                                        s Shutdown since August l4, 2010 Core Status: core in RPV (~D!li~G):

Spent Fuel Pool: 876 bundles; unit's emergency diesel generator 6 available 6 Common Spent Fuel Pool: 6,000 bundles located on land ~ide of Unit4 Electrical Power: Restoration from Switchyard to Unit 2 480v 7 pumps (first) in progress N/A

                                             ---*-**~~
                                             ~uNL            f.~.

Y

OFFICIAL. l:-JSE ONCY Earthquake/Tsunami Status Update March 18, 2011 0600 EDT Fukushima Daini

No changes to report Onagawa
No changes to report Rokkasho

  * . No changes to report Wind shift over land not expected until Sunday; March 20, 2011.

International Response 4 of5 OfMCIAL OSE Ol~EY

OFFICIAL USE ONLY Earthquake/Tsunami Status Update March 18, 2011 0600 EDT Reference Units 1 rem (rem) = 1,000 millirem (mrem) 1 Sievert (Sv) = 1,000 milliSieverts (mSv) = 1,000,000 microsieverts (µSv) 1 rem= 0.01 Sv = 10 mSv

5 of 5

                                        -..Q.EFICIAL USE ONLY

Ot="FteiAL blS5.* ONJ Y . ... Earthquakeffsunami Status Update March 18, 2011 1800 EDT USNRC Emergency Operations Center Sta.tu5, Update March 18, 2011 l:arthqualce / =Tsunami St~tus Upcfate Compiled by Executive Briefing Team This 'report was changed to include NRC's ~ur~nt understanding .of the ongoing situation iri Japan. Historical and background information can be found in past reports. NRC's Top Priorities

1) Continued assessment of radiological conditions, dose projections, and protective action recommendations.

2) Providing technical assistance to the Government ofJapan. *

3) Coordination with other U.S. D~p~rtm~nts and Agencies, the ln.stitute of Nucl.ear Power 0 erations INPO .B~tif'i~'eniraEElectnc~ffiitacliitGEfifs:;t;6 ."'ofElectric:;power::tom. ,'-if .

tt;~~q));,~~cfjt\'~~~,;p'(~(~zmf!itjf' ., ****--* **- ,,,.,.J.,...... ),,,, ..l'Y, -.,-.,., ..,,c- :. *.*., *- -~-Y Status At .0946 EST, March *11, 2011, the NRG entered Monitoring Mode and the agency continues to monitor the unfolding events in Japan. The H~adquarters Operations Center is staffed 24/1.

A total of H NRG expe~s supporting USAID response effort~ from the NRC are in Japan and have engaged. with the 'l,Js Ambassador and his staff.
NRG has Jssued numerous press releases relatep to th~ e~rthquake an~ tsunami. ThesEl press releases can be found online at: http://www.nrc.gov/reading-rm/doc-:-collectJons/news/201.1/

At 0550: EDT, March 14, 2011, the NRC experts in, Japan reported that the Japanese have requested US technical assistance with cooling th~ Fukushima Daiich.i \Jnits, as needed. The effort is being coordinated by the US Ambassador. At 0900 EDT, Ma*rch 15, 2011, the Japanese government accepted DOE's Radiological Assistance Program (RAP) team assistance, which includ,es Aeri.al Measuring System (AMS) flyovers, On Match 16, NRG provided the White House with infQrmation* on protective measures fot NRC staff in .Japan and 'information to provide acMce for otherfederal workers in Japan. The current protective action rElcommendation for l.l.S. citizens residing within 50 miles (80 km) ofthe

Fukushi_ma paiichi site is to evacuate. -

                                                     -1 of 6 Offi"CIAL USE GNL.Y

O~FICIAL USE ONLY Earthquake/Tsunami Status Update March 18, 2011 1800 EDT The US State Department has approved voluntary authorized departure of family members at the U.S. Embassy in Tokyo, the U.S. Consulate in Nagoya and the Foreign Service Institute in Yokohama. Japanese Ministry of Defense appears to be taking on a larger role in the response effort.

r,lj~;\llf~iiR!e~rt: ro~nl@:;12hefrQ~?~~9.Jtie.i1 .~:~:,*'l:nyiJc;>('i~,~".l~kl?J9!~iR":,~,,!JC,¥J,t.e:m~:f_e,~,er~J.

mri):unica1o'.rs'.ijtf{~:iuJsticios}~gijft!i~Q poss1btcfao~stic-;,in,1pacts'from'1tie;ev~nt~,in1Ja'pan:a ~6Ytt9m~~~ImQa~o~ijg:*' * -** * * * * ** * * * * -*** * * *.. * * * * -- *

Status of NRC Licensee and Agree111ent State Facilities NRC is discontinuing reporting status of NRC licensee and Agreement State facilities. NRC will

resurn~ this reportirig should any issues arise related to earthquake or tsunami effects. NRC is currently working on a generic communication for distribution_ to the U.S. nuclear power reactor fleet. The Institute of Nuclear Power Operations (INPO) issued a Level 1 Event Report (highest level) to its members on the afternocm of March 15, 2011. It identifies 4 actions, with due dates, and requires a written response. In general, the actions include walkdowns and verifications of aspects of facility capabilities to address 8.5.b equipment and procedures, Severe Accident Management Guidelines (SAMGs), mitigation of station blackout (SBO) conditions, mitigation of internal and external flooding, and fire and flooding ev(;lnts that could be impacted by a

concurrent seismic event.

~_t~~~l~f§?~'W::{i1~*~~:~<~~!Y~~g&~*~,~~~!~1,;f~~~f)~j~;J~~,l~t~!,B~'.:fy,1~~c,fi*,1l',?20,1.,1_:,

,e~rsp~ctiv~ ort8ad1t;1t1911 R~l~.asestand E.mergeqcyflanJi\!OQ-~.:U~$.'('Jycle~r:,p9w~r,Plants"

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Current Understanding of Japanese Facilities (This information is compiled from TEPCO press releases, IAEA information releases, Federation of Electric Power Companies of Japan, Japan Atomic Industrial Forum, World Association of Nuc:lear Operators, the NRG in-,country team and others.)

Fukushima Daiichi JapElnese national government instructed evacuation for local residents within a 20km radius of the. site boundary and sheltering in place out to 30 km for resid~nts who stayed pehinQ. IAEA confirms a no-fly zone out to 30 km around the Fukushima Daiichi plant. As of 1830 EDT on March 15, 2011, there have been no updates to protective actions. Japanese authorities have changed the cleissification.of the event from a Lev$14 tC> El Level 5 "Accidentwith Wider Consequences" on the International Nuclear and Radiological Event Scale {INES): NHK media report on March 17, 0100 EDT stated that helicopter crews dumping water on Unit 3 reactor building reported dose rates at 375 R/hr at 300 ft. above the building. 2 of 6 CiFFICIAL USE-ONLY

0Ft=ICIAL4:.1$e 0~Y ' Earthquake/Tsunami Status Update March 18, 2011

1800 EDT An array pffire trucks have been deployed at the site and appeared to be supplying / spraying water over Unit 3: *
All available information indicates th~t t.he majority of releases from the Fukushima site have be.en carried out to sea by the prevailing winds. *Foreca!:lt m1,:iteor:ological data f()r the 24 hour period untU 2000 EDT on March 18, 2011 indicates wind headed offshore (from NW/westerly).

DOE Aerial Measurement Tearns have completed ,twt;:> flyovers of the Daiichtsite. NRC has* received the data and the analyses from the first fly-over. Data Y.rqJnJiK~tii?§nif.mf.;py_ef was received by DOE and is being analyzed. * * ** * *

Fukushima Daiic4i STATUS'as of 1500 EDT,'M~1*ch

                                                ..        ,17, 20.11- (04:00. Japan)

Unit 1 - (NRC priority: 4) * * , Core Status: Damaged, extent undetermined C9r~ Cooling: RCS 9epressur1zed (Source: FEPC); sea water injected to cool core (Source: NISA)

Primary Containm~nt: functional (Source:JAIF)*

Secondary Containment: IQst (visuai) Spent Fuel Pool: 292 bundles in poof *(Source: GEH); water level unknown {Source: JAIF); fire trucks are supplying seawater for cooling spray *

Unit ~ - (NRC priority: 3)

Cote Status: damaged, extent undetermined

         *Core Coolitlg: RCS depressurized (Source: FEPC); sea water injected to cool core (Source: NISA)              .

Primary Containment: Possible Torus tjarnage Sec<>ndary Containment: Hole cut in side of fuel floor rnetal to reduce H2 l;)uildup.

         -i~~~mt9§mir5ifft~m1@1~t1l!1~.m:, :                        .
         *spent Fµel Po_ol: 587 bundles in p00J (Source: GEH}; fire, truc,ks are supplying seawc:iter fo.r cooling spray .

Unit ~ .;.. (NRC priority: 1)

Core Status: Damaged, extE!nt undetermined. .

Core Cooling: RCS depressurized '(Source: FEPC): radiation released; sea water injecte<J to cool. c:ore (Source: NISAf. * *

Primary Containment: stafusfuokown Secondary Containment: losi{vlsua])

Spent Fuel Pool: $14 blihdl.esJn pool (~ource: GEH); Pool Dry'(Soutce:*NRC Team); helicopters flew to drop water and water cannon truck sprc;1yed water on Marc_h 17 (Source: METI); fire trucks are supplying seawater for cooling spray *

                                                .* 3 of 6 OF.-RC~NLY

                                      'bFFICIAL
                                        .. '-. .~* . .

USE ONh.¥

                                                 \     -

Earthquake/Tsunami Statu:s Upd~te March 18, 2011 1800EQT Unit.4-,-(NRC priority:2) Cote Status: offloaded core :Cooling: N_/A Primary C.011tainmfi'!nt: NIA

        *secondary Containment:* lost (visual). . _ _             . _        .
        $pent Fuel Pool: 1201 bundles 1li pool (Source: GEH); poOI may be dry; damage to fuel rods suspected (Source: JAIF); wat~r was dumped on site with water cannons; fire trucks are supplying seaw13ter for cooling spray Unit 5..,. Shutdown since January 3, io11 (NRC priority: 5)

Core Status: Core in RPV'(Source: INPd) *

Spent fuel Pool: 950 bunc(les (Source: GEH); Unit 6 emergency. diesel.generator is available Unit 6. - Shutdown since August 14,. 201.0 {NRG priQrity; 6)

Core Status: Core in RPV (Source: INPO) Spent Fuel Pool: 876 bundles (Source: GEH); Uriit'.s ~mergency diesel generator is available. CommorfSpentFuel Pool (NRC priority: 7): 6,000 b'undles (Source: GEH} located on iarid side of Ur,it 4 (yisual} . . Electric:al Power (N~C priority: 7): Restoration from switchyard to Unit 2 48C>V ln pr99ress Other Plants Fukushima Daini

No changes to report Onagawa

No changes to report RQkkasho
No changes to report Protective M_easures Team (PMT)

                    ~~~:::;,w~*;1ai~

ltf1,r,,i1tt&}t-~i!t!~il~~ttJ1lt~[~:;~~tt1i~,~~t1~1:r~:1.ti\lt*~~~:'(3} 4of.8 0 ~ r

Earthquake/Tsunami Status Update

                -.\
                                      *-     March 18, 2011                               1800 EDT Wind shift over land not expected until Sunday, March 20, 2011.

International Response

IAEA sent a two person team to conduct GOordination activities and to take measurements. NRC c:ommunicated with IAEA to discuss the status and c:oncerns.
France has shared technical data with the NRC and publicly posted its assessment of .

projected doses in Tokyo on the IRSN website.

Spain Parliament is still reviewing and deciding on support levels.
Italy is interested in discussing what the USG is doing, atid mjght be interested in helping in some way.
China has offered to help.
Russia has sent a team to Tokyo. The U.S; team has met with the Russians.

     * $~~6rr.cXtri~*w.1n.fiohb'e,*,a~sistfng;.

5 of 6

~LY

r

EarthqUc!kelTs.1.,mami Status ~p9ate March, 18, 2011 1800 EDT Reference Un.its. ,

1 rem (rem}= 1,000 millirem *cmrem) 1 ~iievert (Sv) =1,000 milliSieverts (mSv) =1,000,dOO microsieverts {µSv) 1 rem= 0.01 $v = 10 mSv 6 of6 OFF.ICIAL USE ON~Y

   ..   ~

NRC FORM 464 Part I U.S. NUCLEAR REGULATORY COMMISSION FOIA/PA RESPONSE NUMBER (4-2011) 2011-0135 *2 RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA} / PRIVACY RESPONSE o* FINAL f7l PARTIAL ACT (PA) REQUEST TYPE L!J REQUESTER DATE Diane Curran JUL 2 0 2D11 PART I*.- INFORMATION RELEASED D No additional agency records subject to the request have been located. D Requested records are available through another public distribution program. See,Comments section. D APPENDICES I public Agency records subject to the request that are identified in the listed appendices are already available for inspection and copying at t_he NRC Public Document Room. D IAPPENDicEs* I Agency records subject to the request that are identified in the listed appendices are being made available for

          '                   public inspection and copying at the NRC Public Document Room.

is information on how you may obtain access to and the charges for copying records located at the NRC Public D EnclosedDocument Room, 11555 Rockville Pike, Rockville, MD 20852-2738.

D I~ - - - ~I Agency records subject to the request are enclosed.

APPENDICES D referredRecords subject to the request that contain information originated by or of interest to another Federal agency have been to that agency (see comments section) for a disclosure determination and direct response to you. . 0 We are continuing to process your request. 0 See Comments. PART I.A - FEES AMOUNT' D You will be billed. by NRC for the amount listed.. D None. Minimum fee threshold not met. D You will receive a refund for the amount listed. D Fees waived.

See comments .

for details PART I.B - INFORMATION NOT LOCATED OR WITHHELD FROM DISCLOSURE D No agency records subject to the request have been located. D Certain information in the requested records is being withheld from disclosure pursuant to the exemptions described in and for the reasons stated in Part II. D This determination may be appealed within 30 days by writing to the FOINPA Officer, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001. Clearly state on the envelope and in the letter that it is a '.'FOIA/PA Appeal." PART I.C COMMENTS (Use atta_ched Comments continuation page If required) Group H records relating to your request are being made publicly available in the "NRC's Library" at http://www.nrc. gov/reading-rm/foia/japan-foia-info;html. *

As the NRC makes records publicly available, you will be notified in writing.
FREEDOM(~F I F Y.,AJION ACT M11J PRIVACY ACT OFFICER

          /t?f ,,#Oj           'ff_//'P~MO.                        "

rL': 'SOOm, - - \ "/ . .NRC FORM 464 Part 1 (4-2011)

NRC FORM 464 Part I U.S. NUCLEAR REGULATORY COMMISSION FOIA/PA RESPONSE NUMBER (4-2011) 2011-0118/119/120 8 RESPONSE TO FREEDOM OF INFORMATION ACT (FOIA) / PRIVACY ACT (PA) REQUEST

RESPONSE

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Safety Evaluation Report Mark I Containment Long-Terrri Program Resolution of Generic Technical Activity A-7

Manuscript Completed: March 1980 *ir Date Published: July 1980 Office of Nuclear Reactor Regulation

. *.a U.S. Nuclear Regulatory Commission

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                      .I . REPRODUCED BY U.S. DEPARTMENT OF COMMERCE I,_____
                                  ,     NATIONAL TECHNICAL
                                      'INFORMATION SERVICE SPRINGFIELD, VA 22161 J
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NRC FORM 335 1. REPORT NUMBER fA11i-dbv DDCJ U.S. NUCLEAR REGULATORY COMMISSION 17-77) NUREG-0661 BIBLIOGRAPHIC DATA SHEE!

4. TITLE AND SUBTITLE (Add Voluma No., if 111propri*,e/ 2. (Lelllfe bl1J1Jlt.J MARK* I CONTAINMENT LONG TERM PROGRAM SAFETY EVALUATION REPORT. Resolution of Generic Technical Activity A-7 3: RECIPIENT'S ACCESSION NO_.

7. AUTHORISI 5. DATE REPORT COMPLETED MOl\!TM I VEAR .

C. I. Grimes, USNRC (Task Manager) March * ** *1980

9. PERFORMING ORGANIZATION NAME ANO MAILING ADDRESS (lnclutl/1 Zip Coria/ DATE REPORT ISSUED Office of Nuclear Reactor Regulation MONTI+ j 'VEAR '

U.5. N*uclear Regulatory Commission* July * *** 1980 Washington, D.C. 20555 6. /LHre bl*nlt)

8. (Le.-11 blanlt.J :.** .:

12. SPONSORING ORGANIZATION NAME ANO MAI LING ADDRESS (Include Zip_ Code/

10. PROJECT/TASK/WORK UNIT NO. * *.

A~7 . Same as 9. 1 J. CONTRACT NO.

13. TYPE OF REPORT NUREG - Generic Safety Evaluation Report

\ 15, ~PPLEMENTARY NOTES 14. (Le- blanlt.J '* . ~::~*...

 \~r;.' f'BSTRACT (100 wonli or 1111}                                          _           ,.       .         .                      ~: :**

1

 *-~puring .testing for an advanced Boiling Water Reactor (BWR) c.ontainment system design
 * (Mark Ill}, suppression pool hydrodynam}c loads were identified which .had ,:iot b_een ,.,.

considered in the original design of the Mark I contafoment*systetn. To address this;;. issue, a Mark I CMners Group was formed and the assessment was di.vided into a short-term and long-term program. The results of the NRC sta'ff's revi.ew of..the Mark I Contai!'llllent Short Term Program are described in NUREG-0408.

This report describes the results of the NRC staff's review of the generic Mark I Containment Long Term Program (LTP). The LTP was conducted to provide a generic basis to define suppression pool hydrodynamic loads and the related structural acceptance* criteria~ such that a comprehensive reassessnient of each Mark I containment system would be performed. A series of experimental and*analytical programs were conducted by the Mark I Owners* Group to provide the necessary bases for the generic load defi.nition and structural assessment techniques. The generic methods proposed by the Mark I <Mners Group,_as modified by the NRC staff's requirements, will be used to perform plant-unique analyses, which-will identify the plant modifications, if any, that will be needed to restore the originally intended margin of safety in the Mark I contaf nment designs. )~ .. .. '

17a. DESCRIPTORS

17. KEV WORDS ANO DOCUMENT ArqALVSIS

        .   . .                       \

17b. IOENTIFrERS/OPEN*ENDED TERMS

18. AVAILABILITY STATEMENT 19. SECURITY CLASS (Thi1 f'llponJ 21. NO. OF PAGES Unclassified UNLIMITED 22,PRICE i s

                                                                                     *v,s. oovDIH!IEIIT' Pl!Jfll'D'G   omcE , 19eo ,0.620-l69/ZIIB

ABSTRACT This Safety Evaluation Report' prepared by the staff of the Office of Nuclear Reactor Regulation discusses.suppression pool hydrodynamic loads in boiling water reactor (BWR) facilities with the Mark I pressure-suppression containment design. The report finishes the NRC-'s Generic Technical Acti'vity A-7 (Mark I Containment Long-Term Program), which has been designated an 11 Unresolved Safety Issue 11 pursuant to Section 210 of the Energy Reorganhation Act of 1974. The report describes the g~neric techniques for the definition of suppression pool hydrodynamic loads in a Mark I system and the related structural acceptance criteria. On the basis of a review of the experime'ntal and analytical programs conducted by .the Mark I owners Group. the staff has* concluded that, with one exception*, the proposed suppression pool hyd.rodynamic load definition procedures (as .,. modified by the staff's requirements in Appendix A of this report) will provide conservative estimates of these loading conditions. The exception is t.he lack of* an acceptable specification for the downcomer ncondensation oscillation" loads. In addition .* requirements for confirmatory analyses and testing have been identified. The resolution of these issues will be described in a supp 1ement to this report. The staff also has concluded that the proposed structural acceptance criteria are consistent with the requirements of the applicable codes*and standards.

In conjunction with the general structural analysis techniques, these criteria will provide an acceptable basis for establishing the margins of safety in t_he Mark I containment design. iii

           ~eceding page bla~hl

t r*

CQNTENTS ABSTRACT. iii ACKNOWLEDGMENTS xi NOMENCLATURE . . . *x; ii

1. INTRODUCTION .. . . 1 1.1 Problem Definition . . . 1 1.2 -Short~Term Program Summary . . . . * ** 5.

1.3 Long-Term Program Description * . . . . 5

2. BACKGROUND . . . . . . . . . . . . . . . 8 2.1 Mark I Containment System Description . * . 8 2.2 LOCA-Related Hydrodynamic Phenomena* .. 11 2.2.1 Poe~ Swell Phenomena * . . . * . 11 2.2.2 LOCA Steam Condensation Phenomena 14 2.3 Safety-Relief Valve Discharge Phenomena .. 16 2.4 Long-Term Program Task Descriptions . . . 17

3. HYDRODYNAMIC LOAD EVALUATION .. . . . . ... . . . . 23

     . 3.1 Introduction . . . . . . .                                          23 3.2 Containment Response Models                                         23 .

3.2.1 Postulated Pipe Breaks . . . 24 3.2.2 Event Combinations and Timing . . . 26 3.2.3 Containment Mass an~ Energy Release 28 3.3 Vent System Pressurization and Thrust Loads 29 3.4 Torus Pool Swell Pressure Loads . *. . . 31

3. 4.1

Net Torus Vertical Pressure Load . .34 3.4.2 Torus Pressure Load Distribution. 40

3. 5 Pool Swell Impact and Drag Load~. . . * . . . 41 3.5.1 Vent System Impact and Drag. . . . . . 42

3. 5. 2 Vent Header Deflector Impact and Drag. . . . , 45 3.5.3 Impact and Drag on Other Internal Structures. 50

3. 6 Poo 1 Swe 11 Froth. Impingement Loads. 67 3.7 Pool Fallback Loads . . . . . ¥ ***** 74 3.8 Condensation Oscillation Loads. 76 f Preceding page bl~

V I L

\*

CONTENTS { co*nt i nued) 3.8.1 Condensation Oscillation Torus Shell Pressure Loads . . . * . . . . . .

82 3.8.2 Condensation Osci*ll at i ori Downcomer Loads
85 3.8.3 Condensation Oscillation Vent System Pressure Loads . . ..
88 3.9 Chugging ~oads . . 89 3.9.1 Chugging Loads on the Torus Shell. . .*. 89

3. 9. 2 Chugging Downcomer Loads . . . . * * . . 93 3.9.3 Chugging Vent.System Pressure Loads. 97 3.10 Safety-.Rel i~f Valve Discharge Loads ***. 97 3.10. l SRV Di~cha.rge Line Pressure Transient . 99 3.10.2 SRV Air-Clearing Torus Pressure Loads. 100 3.10. 3 SRV Reflood Transient' * . . . 119 3.10.4 SRV Quencher Thrust Loads . * . * .. * .. 121 3.10.5 SRV Temperature Transients . * * * . . . . 122 3.10. 6 SRV Discharge Event Cases . , * ,. . . : ; 123 3.10.7 Suppression Pool Temperature Limit. 124 3.11 Submerged Structu~e Drag Loads. '. .. ~

127 3.11.l LOCA Water~Jet Loads . * . . * * . 128 3.11.2 ~OCA Pool Swell Bubble-Drag Loads . . .
129 3.11.3 LOCA Condensation Osc;11ation Drag Loads. 133 3.11.4 LOCA Chugging Drag Loads . . * . . 135 3.11.5 SRV Water-Jet Loads . * . * * . . . * *
136 3.11.6 SRV Bubble-Drag Loads . . . * * . . . . . 136 3.12 Secondary Loads and.Other Considerations. 137 3.12.1 Seismic Slosh . . . . * * . . * . . .138 3.12.2 Post-Pool Swell Waves . . . * * . 139 3.12. 3 Asymmetric Vent System Flow *** 139 3.12.4 Downcomer Air-Clearing Loads . . . .*' *. 141 3.12. 5 Sonic and Compression Wave Loads. 141 3.12. 6 Downcomer Submergence and P.ool Thermal Stratification . * . . . . . . . . . . 142 3.12.7 Differential Pressure Control . . . ; . 143 3.12.8 *sRV Steam Discharge Loads . *-: . . . . . 146

                                  '            I

4. STRUCTURAL AND MECHANICAL.ANALYSES AND AC~EPTANCE CRITERIA. 147 4.1 Introductfon. . . * * . * . *
147 4.2 Classif;cation of Structures. 149 vi

                                                              '. . ~

CONTENTS (Continue~) Page 4.2.1 Pressure Suppression System ** 149 4.2.2 Attached Piping System .*..* 149 4.2.3 Internal Structures . . . . . . 150

4. 3 Service Limits and Associated Load Combinations* ,'. . 150 4.3.1 Service Limits . . . . . * . . . . . . . . 151 4.3.2 Applicable Code Sections . . * . . . . . . 156 4.3.3 Service Level Assignments . . * . . . . . * . 157

          ,4.3.4 Operability and Functionality Requirements.               163 4.4 Analysis Techniques . . . .                                 ..   ,166 I

4.4.1 General *Guidelines . . . . ... 166

4. 4. 2 Damping. . . .* *. . . . . . . . . .

167 4.4.3 Combination of Structural Responses. 167

5. . CONCLUSIONS. . * . . . . . . . . . . . . . . . . 169

6. REFERENCES . * * * . . . . . . * . . . . . . . * .

172 APPENDIX A - NRC ACCEPTANCE CRITERIA FOR THE MARK I CONTAINMENT LONG~TERM PROGRAM. . . . . . . . . . . . . . . . A~l APPENDIX B - LETTER TO THE CHAIRMAN, USNRC, FROM THE ADVISORY COMMITTEE ON REACTOR SAFEGUARDS. . B~l vii i

LIST OF *FIGURES Page 2.1-1 Mark I Containment System .. 9 2.1~2 Mark I Suppressi~n Chamber 10 2.2-1 tOCA Sequence of Primary Events . 12 2.. 3-1. . Marie I T-Quencher Discharge Device ..* .

18 3.2-1 Typical Mark I DB~ Pressure Response. 25 3.Z:*2 Hark I Event Combinations * . ** . . . * . . . :* 27 3,4.:1 Mark I Torus Vertical Pressure Transient ..... .* 35 3:5-1 Mark I Vent-Header Deflector Designs . ~ . . 46 3.5-2
Typi'cal Cylindrical Target .Impact Pressure Transient. . *.. 53 3.5*3 Cylindrical Target Impact.Transient Approximation . . 55 3.5*4 Cyl i ndri ca 1 Target Drag Coefficient Following. Impact . 57 3.5*5 Typical Flat Target Impact Pressure Transient 60 3;6-1 . Froth Impingement Zone -*Region I .. 68 3.6*2 Froth Impingement Zone - Region II . . . 69 3.6-3 * .Vent*Header Impact .Wave Formation . : 71 3.7-1 'Pool Fallback Load Directional Range. 77 3.8-1 Mark I Full-Scale Test Facility * . .. . . . . . *... 79 3.8-2 Condensation Oscillation Torus Shell Pressure Transient .. 80 3.8-3 Condensation Osei l lation Amplitude - Frequency Spectr.uni .* 84 3.8*4 Downcomer Condensation Oscillatio'n Load Histogram . . . . . 87

3. 9*1 Chugging Torus Shell Pressure Transient * . * . . . . . . . 90 3.9-2 Chugging Asymmetric Torus Shell Pressure . . . * . . . . . 92.

3.9-3 Multiple Downcomer Chugging Load Probability Distribution, 95 3.10-1 Mark I T*Quehcher Discharge Device . . . . . . . . . . . : . 98 3.10-2 Typical T-Quencher Shell Pressure Transient . . . . 113 3.11-1 Comparison of Drag Forces in Accelerating Flows . 131 3..11-2 Comparison of.Drag Forces in Oscillating Flows .. 132 4.3*1 Event Combinations and Service Levels for Class MC Components and Internal Structures . . . . . . . *. . . . 152 4.3-2 Event Combinations and Service Levels for Class 2 and 3

        . - Piping . . . . . . . . . . . . . . . . . . . .* .                  153 4.3-3         Event Combinations and Load Facto*rs for Concrete Structures. . . . . . . .                 . ...                 154 viii

I LIST OF TABLES Page* 1.1-1 Domestic BWR/Mark I Facilities. 2 2.4-1 Mark I Long-Term.Program Task . 19 3.4-1 Mark I Pool Swel 1 Test Programs ..* 34 3.8-1 FSTF Test Matrix . . . . . . . . . . . . . . . . 81 3.10-1 Comparison of Mark I SRV Parameters . . . . ; . . . . 103 3.10-2

C.ompari son of Quencher Geometries and Test Conditions 105 3.10-3 Comparison of Mark I T-Quencher Load .Trends . ~ * *~ *. 107 4.3-1 . Structural Criteria Symbol*Definit1on 158"

                                                                                ,.I
                                                                                ~

f ix

I.. l__J

ACKNOWLEDGMENTS A-7 REVtEW TEAM The following individuals participated in the Mark I Containment Long-Term Program Safety Evaluation and contributed substantially

                                               .          .to tMs Report:

C. I. Grimes, USNRC, Division of Operating Reactors (A-7 Task Manager) J. R. fair, USNRC, Division of Operating Reactors K.- R. Wichman, USNRC, Division of Operating Reactors

T. M. Su, USNRC, Division of Systems Safety (A-39 Task Manager)

J. D. Ranlet, Brookhaven. National Laboratory G. Maise, Brookhaven National Laboratory R. L. Kosson, Brookhaven National Laboratory (Gruniman Aerospace Corporation) C. Economos, Brookhaven National Laboratory C-. Brennen, California Institute 01'. Technology A. A. Sonin, Massachusetts Institute of Technology G.-Bienkowski, Princeton University IPreceding page blank I xi

'-~ J

NOMENCLATURE ADS automatic depressurization system ASME American Society of Mech.anical Engineers BWR boiling water reactor CDF cumulative distribution function OBA design-basis accident DLF dynamic load factor ECCS emergency core-cooling system EPRI Electric Power Research Institute FSAR Final Safety Analysis Report FSI.. fluid-structure interaction FSTF Full-Scale Test Facility GE General E"lectric Company HEM homogeneous equilibrium model HPCI high-pressure coolant injection IBA intermediate-break accident KWU Kraftwerk Union AG, West Germany LCO limiting conditions for operation LDR Load Definition Report LLL Lawrence Livermore Laboratory LOCA loss-of~coolant accident LTP

long-term program MVA multiple-valve actuation NRC Nuclear Regulatory Commission PAP Program Action Plan PSTF Pressure-Suppression Test Facility PUA plant-unique analysis PUAAG plant-unique analysis-applications guide QSTF Quarter-Scale Te.st Fadlity RHR residual-heat-removal system RSEL resultant-static-evaluation load SBA small break accident SER Safety Evaluation Repor.t SRSS square root of the sum of the squares SRV safety-relief valve SRVDL safety-relief valve discharge line STP short-term program SVA single-valve actuation TAP Task Action Plan

     / Preceding page bl~

xiii

MARK I CONTAINMENT LONG-TERM PROGRAM SAFETY EVALUATION REPORT

1. INTRODUCTION Pursuant to Section 210 of the Energy Reorganization Act*of 197.4, the capability of the boiling water reactor (BWR) Mark I containment suppression chamber to withstancf suppression pool hydrodynamic: load~ which were not considered.in the original design of the structures was designated an "Unresolved Safety Issue11 (Task Action Plan A-7), This report describes the gene,.ic suppression pool hydrodynamic load definition and_ structural_ assessment techniques that are to be* used to design plant modifications *necessary to restore the margins of safety in the containment structures of the BWR/Mark I facilities. The staff has reviewed the experimental and analytical programs, *and has concluded- that the assessment procedures, as ~odified by the requirements set forth in Appendix A

( NRC Acceptance Criteria for the Mark I Containment Long-Term Program ) ~ wi.11 11 11

provide a cons*ervat_ive evaluation of the structural response to suppression pool _hydrodynamic loadfog events.

The designation of the requirements in Appendix A constitutes the_ resolution of TAP A-7. Ll Problem Defini.tion The first generations of General Electric (GE) BWR nuclear,$team supply systems are housed in a containment.structure designated as the Mark I containment system. A total of 25 BWR facilities with the Mark I containment system have be.en or are being built in the United States; of these, 22 are licensed for power operation.

A listing of the domestic BWR/Mark I facilfiies fs provided in Table 1.1-1.

The original design_of the Mark.I containment system considered postulated accident loads previously associated with containment design. These included pressure and temperature loads associated with a loss-of-coolant accident "(LOCA), seismic loads, dead loads, jet-impingement loads, hydrostatic__ loads due. to water in the suppression chamber, overload pressure test loads, and construction loads. 1

Table 1.1.1 Listing of Domestic BWR Facilitie*s with the Mark I Containment System Plants Licensed for Power Operation Licensee Browns Ferry Units 1, 2, and 3

Tennessee Valley Authority Brunswick Units land 2 Carolina Power and Light Cooper Station Nebraska Public Power District Dresden Units 2 and 3 Commonwealth Edison Company Duane Arnold Iowa Electric Light *and Power FitzPatrick Power Authnrity State of New York Hatch Units land 2 Georgia Power Company Millstone Unit l Northeast Nuclear Energy Company Monticello Northern States Power Company Nine Mile Point Unit 1 Niaga*ra Mohawk Power Corporation
oyster Creek Jersey Ce~tral Power and Light Peach Bottom Units 2 and 3 Philadelphia Electric Company Pilgrim Unit 1 Boston Edison Company Quad Cities Units land 2 Commonwealth Edison Company Vermont Yankee Yankee Atomic Electric Company Plants

 . Under Construction
                      .                       Applicant Fermi Unit 2                                  Detroit Edison Company Hope Creek Units 1 and 2                      Public Service Electric and Gas 2

However, since the establishment of the original design criteria, additional loading conditions which arise in the functioning of the pressure-suppression concept utilized in the Mark I containment system design have been identified. In the course of performing l~rge-scale testing of an advanced design pressure~ suppression containmeht (Mark III), ~nd during in-~lant testing of Mark I contain-

ments, new suppression pool hydrodynamic loads which had not explicitly been included in the original Mark I containment design.basis were identified. These additional loads result from dynamic effects of drywell air and steam being rapidly forced into the suppression pool (torus) during a postulated LOCA and from suppression pool response to safety-relief valve_(SRV) operation generally associated with plant transient operating conditions. Because these*hydrodynamic loads had not been considered in the original design of the Mark I containment, the staff determined that a detailed reevaluation of the Mark I containment

  . system was required.

To better u~derstand the reasons for reevaluating the Mark I containment.design, the historical *development of the original Mark I containment design basis must be reviewed. The Mark I containment design was based on experimental information obtained from testing performed on a pressure-suppression concept for the Humboldt _Bay Power Pl ant and from testing performed for the Bodega Bay Pl ant concept. The purpos~ of these initial tests, performed from 1958 through 1962, was to demonstrate the viability of the pressure-suppression concept, for reactor contain-ment design. The tests were designed to simulate LOCAs with breaks in piping sized up to approximately twice the cross-sectional break area of the design-~asis LOCA. The tests wer.e instrumented to obtain quantitative information for.establishing containment design pressures. The data from these tests were the pri.mary experi-mental bases for. the design and the initial staff appr~val of.the Mark. l containment system. During the large~scale testing of the Mark III containment system design, in the period 1972 through 1974,, new suppression pool hydrodynamic loads were identified for the postulated LOCAs. GE tested the Mark III containment concept 3

 , in its Pressure Suppression    ' .     .

Test Facility*(PSTF)

(Ref. 1). These tests were i nit i.a~ed f o,r the Mark I II. concept because of confi gurat iona l differences between

  . the previous containment concepts and the Mark III deslgn. More sophisticated inst~umentation was available for the Mark III tests, as were computerized *
 . methods for data reduction. It *was fr~m the PSTF te~ting that the short-term.

dynamic effects of drywell air being forced into the pool in the initial stage of the postulated LOCA were first identified. This air injection into the suppression pool water results in a pool swell event of short duration. In this event, a slug of water rises and impacts the unders;de of structural components withfo the suppression chamber . In addition .to the .information obtained from the PSTF data, other LOCA~related dyna~ic . . load information . was. obtajned from foreign testing programs (Ref. 2) f~r similar pressure-suppressfon cont~inments. It was from these fore_ign tests that oscillatory condensation loads.during the later stages of a postulated LOCA were identified. Als.9,; experience at operating plants indicated that SRV discharges to th~ supp,:~~sion pool "!O~ld cause oscillatory hydrodynamic loads on the suppression chamber. Both. the LOC~. and SRV discharge are characterized by an i nit i a1 short-period injection of air into the suppression pool, followed by a longer period of steam discharg~ into the suppression pool. .:*1

1*
Consequently, in F~br~ary and April 1975, the NRC t~ansmitted letters to all utilities owning pwR fa.cilities with.the'Mark I containment system des.ign, requesting \~at the owners quantify the hydrodynamic loads and assess the effect of these . lo.ads .on .the containment . . structure.

                                                     .          The February 1975 .letters reflected N~C concerns about the dyna~ic loads from SRV discharges, while th~ April 1975

~ letters indi~ated the ~eed to evaluate the containment respo~se to the newly identified dynamic loads associated with a postulated design-basis LOCA .. As a result of t~ese letters from the NRC. and recognizing that. the apditional ._ evaluation effort would be very similar for all Mark I BWR plants, the affected utilities f~rrned an "ad hoc 11 Mark I Owners Group, and GE was designated as the 4

Group's lead technical organization. The objectives of the Group,were to deter~ mine the magni~ude and significance of these dynamic loads as quickly as possible and to identify courses of action needed to _resolve any outstanding'safety. co~cerns. The Mark I Owners Gro_up proposed to. dfvide this task into two programs: a short-term program (STP).*to be completed in early 1977 and a fong.:tenn program* (LTP) to be completed in 1979. 1.2 Short-Term Program Summary. The objectives of the STP were to verify that each Mark I containment system wou.ld maintain its integrity and functional capability when subjected to the most probable loads induced by a postulated design-basis LOCA, and to* verify that licensed Mark I BWR facilities could continue to operate safely, without_ endangering the heal;h and safety of the public, while a method1cal 1 compreh*en.:. sive LTP was being conducted. The STP structural acceptance criteria used to evaluate the design of the torus

and re 1ated structures were b.ased on providing. adequate margins of safety. i*. e .
a safety-to-failure

           .          factor of 2, to justify continued operation of the plant before the more detailed results of the LTP were available.

The bash for the staff's conclusions relative to the STP are described in the "Mark I- C~ntainment Short-Term Program Safety Evalu~tion Report. 11 NUREG_-0408, dated December 1977. The staff concluded that a *~ufficient margin of safety had been demonstrated to assure the functional performance of the containment system and. therefore. any und.ue risk to the hea1th and safety of the* public was precluded. Subsequently, the staff granted the* operating M~*rk I _facilities

                                                                      . of exemptions. relating to the structural. factor of sa-fety requirements 10 CFR 50.SS(a). These exemptions were granted ~or an interim period of approximately *2 years, while the more comprehensive LTP was being conducted.

1.3 Lon~-Tenn Program. Description The objectives of the LTP were to.establish design-basis (conservative) Joads that are appropriate for the anticipated life of each Mark I BWR facility (40 _years)., and to restore the originally inte_nded design-safety ma~gins for each Mark I containment system. 5

During July and August 1976, the Mark I Owners Group made several p_resentations to the NRC staff regarding the proposed content and schedule for completion of the LTP. Much of this information was subsequently documented in the ~*Mark I Containment Program, Program Action Plan 11 submitted to the NRC staff on October 29, 1976 (Ref. 3). As a result of_-NRC staff comments and ' questions on this document, the Mark I Owners Group revised severai of the proposed LTP tasks and objectives. These revisions were discussed with the NRC staff 'in meetings held ~n February 1977 and are documented

         . 11        in *Revision 1 to the 11 Mark I Containment Program, Program.

Action .Plan which was submitted on February 11, 1977 (Ref. 4). During. the.

                   .                           I    .                  .

course of the LTP, addit~onal rev_isions were made to the Program Action Plan (Refs. 5, 6) to reflect task scope and schedule changes wh;ch evolved from the initial results of specific tasks. The principal thrust of the LTP has been the development of generic methods for the definition of suppression p_ool hydrodynamic loading' events and the associated st~uctural assessment-techniques for the Mark I ~onfiguration. The generic.analysis t~chniques are intended to-be used to perform a plant-unique* analys.is (PUA) for each Mark I facility: This* analysis wou*ld demonstrate 'that the proposed configuration of the plant has restored the original design-safety margin. The generic.aspects of the Mark I Owners Group LTP were completed with the sub-mittal of the 11 Mark I Containment Program Load Definition Report 11 (Ref. 7) hereafter1'eferred to as the LOR, and the 11 Mark I Containment Program Structural Acceptance Guide" (Ref. 8), hereafter referred to *as the PUAAG; as.well as supporting reports on the LTP experim~ntal and analytical tasks~ The purpose of this report is to present the staff 1 s ev~luation of the generic load definition and structural assessment techniques that.have been proposed

by the Mark I Owners Group in the reports mentioned above.* The requirements which have resulted from the staff evaluation (Appendix A) will be used by each BWR/Mark I licensee to perform plant-unique analyses. T~ese analyses will se~ve to identify those plant modifications that are needed to restore the margins of safety in the containment design.

6

Section 2 of this report presents a general description of the Mark I contain-ment system and the phenomena associated*with suppression pool*hYdfOdynamic ~oading events. A more detailed descri.ption of the hydrodynamic phenomena is presented in Section 3, along with the staff's evaluation of the load definition techniques proposed in the LDR. Section 4 presents the staff's evaluation of the general structural analysis techniques and acceptance criteria that are to be used for the plant-unique analyses. 7

2. BACKGROUND

2.1 Mark I Containment System Description*

The Mark I containment system is_designed to ~ondense the steam released during a postulated LOCA, to limit the release of the fission products associated with the accident, and tp serve as a source of ~ater for the emergency core.cooling sys tern ( ECCS) .. The Mark I contai~ment system (Figures 2.1~1 and 2.1-2) consists of (1) a drywell whi:ch en_closes the reactor vessel, the reactor coolant recirculation system, and other branch conrections of. t*he reactor coolant system; (2) a torodial

shaped pressure-suppression*chamber (torus) containing a large volume of water; (3) a vent system connecting the drywel.l to the water space of the torus; (4) contain-ment isolation valves; (5) containment cooling systems; and (6).other service equipment.

The drywell is a steel pressure vessel, . supported . in concrete, with a spherical lower section and a cylindrical *upper section. For all.but one of th~ Mark I facility designs, the suppression chamber is a ~teel pressure vessel in the* shape o! a torus, l~cated below the.drywell and*encircling it. The steel sup-pression chamber is mounted on supports which transmit operational, accident, and seismic loads to the concrete foundation of the reactor building. The reinaining Mar~ I design -utilizes a *steel-lined, reinforced concrete suppression ;:*

chal!lber;*~-l~o 'in the shape of a torus ..

. The drywell and suppress~on chamber volumes are interconnected by a vent* system. Main vents connect the drywell to a vent header, which is located in the airspace of the suppression c:hamber.

A bellows in each main vent allows for pos*sible m*ov..ement of *the suppression chamber .relative to the dr.ywell (e.g., the.rinal expansi*on).

Pr~jecting downward *from the. vent t)eader are. do\lo'.ncomer pipes, .w~ich are nominally 24 inches in diameter and terminate 3 to 4 feet below the surface of the pool. Typically there .are 8 ~o 10 main vents and 48 to 120 downcomers. 8

SUPPRESSION VE NT HE AD ER CH AM BE R (TORUS) & OO W NC OM ER S Fig~re 2.1-1 Mark 1 containment system 9

TOP VIEW TORUS SHELL NOMINAL POOL WATER LEVEL. RING GIRDER SUPPORT Figure 2.1-2 Mark I suppression chamber.

In the event of a postul~ted' LOCA, reactor water and steam would expand into the drywell atinosphere .. As a result of the increasing dl"ywell pressure, a mixture of drywell atmosphere, steam, ahd water .would be forced through the vent system into the pool of water which is stored in the suppression chamber. The stea~ vapor would condense in the suppression pool, thereby reducing the . drywell pressure. Noncondensible gases and fission products would be collected and contained in the. suppression chamber. Initiany, the drywell atmosphere is transferred to the suppression chamber and pressurizes the chamber. At the end of the blowdown, when ECCS water spills out of the break and rapidly reduces_ the drywell pressure, the suppression chamber is-vented to the drywell through installed vacuum breakers to equalize the pressure between the'two vessels. The ECCS cools the.reactor:- core and transports the heat-to the water in the suppressio.n chamber. Cooling systems are *provided to remove heat from* the- water

in,the suppression chamber, thus providing a continuous path for the removal of decay heat from the primary system..

2.2 LOCA-Related Hydrodynamic Phenomena The following sections contain a *qualitative description of the various phenomena* that could occur curing the course of a postula.ted design basis LOCA in a BWR with the Mark I containment .system, as well as ii description of the hydrodynamic loads which .these phenomena could impose upon the suppression .chamber and related structure._ Figure 2.2-1 shows the sequence of eyents after a postulated LOCA and the potential loading conditi*ons associated with these events. 2.2.1 Poor Swell Phenomena With* the instantaneous rupture of a steam or recirculation line, a shock wave ' exits the broken *p~imary system pipe and expands into the drywell at~osphere: At the break exit point, the* wave amplitude theoretically is equal to reactor operating

       . pressure (1000 psia); however,   . there would.be rapid attenuation.as the wave front expands spheri ca*l ly outward into the drywe 11. Further attenua-tion would occur as the wave enters the drywell vent system*and p_rogreues .i"nto the suppression pool.

11

PHENOMENON POTENTIAL DYNAMIC LOADING CONDITION

                     ,, ...,. : t                                ::'

PIPE BREAK - LOCA e COMPRESSION WAVE

..-

INCREASE IN VENT SYS'.l,'EM STATIC PRESSURE e START OF VENT SYSTEM THERMAL TRANSIENT DOWNCOMERS CLEARED OF WATER '

e WATER-JET LOADS ON TORUS AND AIR FLOW BEGINS SUBMERGED STRUCTURES

                                                 --    e VENT SYSTEM REACTI9N LOADS eBUBBLE.LOAD ON TORUS - DOWNLOAD     ,

BULK POOL SWELL

                                                      *noWNCOMER AIR-CLEARING LOAD
                                                ... e IMPACT LOADS e TORUS COMPRESSION - UPLOAD e DRAG LOADS ON SUBMERGED STRUCTURES POOL BREAKTHROUGH I
                                                ~    I* FROTH IMPINGEMENT LOADS               I FROTH POOL SWELL                  I I

-I

FALLBACK LOADS I POOL FALLBACK CONTINUED AIR/STEAM FLOW I

e TORUS PRESSURIZATION

                                               ..-    e POST-.SWELL WAVE LOADS e FLOW REACTION LOADS ON VENT CONTINUED STEAM FLOW SYSTEM
                                       ' !    .-      e PRESSURE OSCILLATIONS e DOWNCOMER LOADS BLOWDOWN OVER ECCS REFLOOD
                  -                 .,        ......

NEqATIVE PRESSURE ON VENT LONG-TERM HEATUP SYSTEM . .

                                              ..-     e THERMAL LOADS e SECOND PRESSURE PEAK +/-N TORUS Fig~re 2.2-1 LOCA sequence of primary events.

12

Because there would be a very rapid drywe 11 pressure increase _associated with the postulated LOCA, a compression wave would propagate into the water initially standing. in the downcomers.- Before this wat'er is cleared. from the downcomers, this compression wave would propagate. through the suppression pool a~d result in a dynami_c loading on the suppression *chamber (torus). The compression wave could also result in a dyna(llic loading c.o_ndition on any structures w.ithin the suppression pool. Immediately following the postulated LOCA, the pressure and temperature of the drywell atmosphere would increase. These increases also wou.ld occur in the .* vent system and woul'd lead to mechanical and thermal load*ings on the vents, vent header, and downcomers. With the drywell pressure increase, the water 'initially standing in.the down-

  *comers accelerates into the pool, and the downcomers clear of water. During this w~ter-clearing process, a water jet forms in the suppression pool°, ari'll" causes a potential water-jet-impingement load on the structures wi_thin .the-~.

suppression pool and on the torus section beneath the downcomers. .,. Imme~iat~Jy following downcomer clearing, a bubble of.air starts to form*at the exit of the downcomers. As the bubble forms, its* pressure is nearly equa*1 to the drywell pressure at the time of downcomer clearing. The bubble pressure is transmitted through _the suppression pool water and results in a downward load on the torus. When the air/steam flow from the drywell becomes established in the .vent system, the-initial bubble expands and subsequent1y decompresses as a.result of over-expansion. Duririg the early stages of this -process; the pool will swell in. bulk mode (i.e., a l_igament of solid water is *being *accelerated upward by the air bubble). During this phase of pool swell, structures close to the pool I

   ~urface experience impact loads as the rising pool surface strikes t~e lower surfaces of the structures. This is followed by drag loads as* the pool s~rface continues to rise past the structures. In addition to these impact and drag loads above the pool, there will.. also be drag loads as *the bubble formation causes water flow past submerged structures and equipment.

13

As the ~ater slug continues to rise (pool swell), the bubble pressure falls below the torus airspace*pressure. However, the momentum of the water slug causes it to continue to rise, this compresses the air volume above the pool and results* in a net upward pressure loading on the torus. The thickness of.

the water slug will decrease as it rises. Aided by impact of the vent header, it wi 11 begin to break up and evolve into a two-phase **u froth" of air and water. The froth will continue to rise as a result of i_ts own momentum, and it will impinge on structures above the pool breakthrough elevation. When the drywell air flow rate through the vent system decreases and the air/ water mixture in the suppression pool experiences gravity-induced *phase separa-tion, the pool liquid*upward movement stops, and the 11 fallback 11 process starts. During this process, structures in the torus may experience a *downward loading, and the *submerged portion of the torus could be subjected to a pressure increase. Following *11 fallback/' waves may develop on the suppression pool surface, thereby presen~ing a potential source of dynamic loads on the downcomers, torus, and any o.iher structures close to the water surface. The poQl swell transient.typically lasts on the order of 3 to 5 seconds.* Because of th.e configuration *of the drywell and the volume *of the vent system, this period is dominated by the flow of the drywell atmosphere* through the vent system. Steam flow will follow, beginning near the end of the pool swell transient, with a relativ.ely high concentration of noncondensible g*as. Through-out' these periods, there* is a significant pressure differential between the drywel l and the torus. TMs, together with flow-induced reaction forces, leads to structural loads on the vent system. 2.2.2 LOCA Steam Condensation Phenomena* As the flow of steam through the vent system continues, pressure oscillati'ons will occur in the event system and th~ suppression pool. Experimental data suggest that the amplitude and frequency of these pressure oscillations are

 *The dr~ell atmosphere for most operating BWR facilities is inerted      (~.e .*

nitrogen rich). However, pool swell experimental studies conducted for this program used air as the flowing medium, because of its availability and the thermohydraulic similarities of air and nitrogen. In addition, the terms. drywell atmosphere and drywell air are often used interchangeably. 14

primarily functions of the mass flow rate through the vent system,. the concen-tration of noncondensibles in the mass flow, the downcomef'. submergence, and the suppression pool te~perature. The pressure oscillations. will 'cause loadings on the vent system, the torus shell, and the structures submerged in the pool. Early i.n the transient, when* t~e. mass flow rate is relatively high,* the pressure* oscillations appear*as a sinusoida~ *function whose ~mplitude varies with time. These oscillations are referred to as "condensation oscillations." When the mass fl ow rate through the vent system decreases, the poo 1 wi l, 1 begin to reenter the downcomers intermittently. This period, termed 11 chuggfog, 11 is characteriz.ed _by fairly irregular pressure pulses. The ECCS is designed so that shortly after a.postolated LOCA, the ECCS will automatically start to pump condensate water and/or suppression pool *water into

. the reactor pressure    vessel. This   water floods the reactor core
,"                .                  .                                . and subsequently cascades into the drywell through the postulated break. The, time at which this will occur depends upon break size *and location. Because the drywell will be full of steam when the vessel floods, the sudden introduction      of water causes*;

steam condensation and dr.ywell depressurization. As the (1rywe]1 pressure falls below the torus pressure, the vacuum rel f ef systen:i allows. air from the torus

 ,to enter the drywell. Eventually, enough air*wi11 return to equalize the drywell

~net torus pressures; however, during this drywell depressurization transient, there will be a period of negative pressure on the vent system within.. the torus volume. When the mass flow from the break is small, the pressure oscillations will essentially be term.inated. ,*

Following vessel flooding, suppression pool water is continuously recirculated through the core by the ECCS pumps. The energy associated with the core decay' heat will result in a slow heatup of the suppression pool. To.control suppres- . sion pool temperature, operators will activate the suppression pool cooling mode of, the residual-heat-removal (RHR) system. 'After several hours~ the RHR heat exchangers will termfoate the increase in the suppression pool temperature. An increase in the pressure in the drywell and torus is associated with this post-LOCA suppression pool temperature increase_;. however, th~ resultant maximums wi lJ not exceed the pressures that occur during the~ short-term blowdown phase of the accident. 15

2.3 Safety-R_elief Valve Discharge Phenomena BWR plants are equipped with safety-relief valves (SRVs) to control primary *

.system pressure transients: The SRVs are mounted on the main steam lines inside the drywell, with discharge pipes routed down the main vents into the suppression pool. When an SRV is actuated, steam released from the primary system will be discharged into the suppression pool where it will condense.

Small. variations

                      .in primary system pressure. can be controlled by changing*the system power level. However, more rapid pressµre transients (e.g., turbine trip)*require*a positive- acting relief system. For_these transients, the SRVs actuate.to divert part or all of the generated steam to the suppression pool.

The numo~r of SRVs in any particular plant is dependent upon the configuration and rated pow~r of ihe primary system. The SRVs will either self-actuate at a preset pressure (nominally 1100 psia)_or actuate by an external signal (e.g., nianual actuation). A specified number 'of t_he SRVs is used for the automatic depressurization system {ADS), which is designed to reduce the reactor system

pressure to permit the l~w-pressure emergency core spray and/or the low-pressure coo~ant

      . . injection systems. to .function. .The ADS performs this function by*

aut.ol)latically _actuating*the specified SRVs, following the receipt of specific sig~als from the r~actor protection system. Upon actuatio.n of an SRV, the air column within the partially *submerged discharge 1 i~e is c*ompressed by t~e high-pressure steam and *accelerates the water leg

. i_nto the sup_p,ression pool. The water je,ts thus formed create pressure and

. velocity transients which c~us~ drag or jet impingement loads on submerged structures: Following water clear~ng, the ~ompressed air is accelerated into the suppres-

sion pool and forms a high-pressure air bubble. This bubble expands and contracts a number of times before it rises to ,the suppression pool surface. The associated transients again create drag loads on submerged structures, as well as pressure loads on the submerged boundaries. These loads are referred to as SRV air-clear.ing loads. 16

Following the air-clearing phase, essentially pure .steam is injected into the pool. Exper1ments indicate that the steam jet/water interface which exists at the discharge li'ne exit js relatively stationary, as long as* the*local pool temperature is low. T_h_us, condensation proceeds in *a stable manner, *and' no ' . significant loads are experienced. Continued steam blowdown into' the pool will'. increase the local pool temperature. The condensation.rates at the 'turbulent* steam/water interface are event~ally .reduced to levels below* those' needed* to** readily condense the discharge steam. At this."threshold 11 level, the condensa-tion process becomes. u11stablei i.e.*,* ~team bubbles* are formed and shed- from* the pipe exit, and the bubbles osci-llate and coHapse. 'This results in s*evere pressure oscil'lations, which are imposed on the pool- boundaries. To preclude

unstable condensation, _l_imits are established for the allowable suppres'sion pool temperature and are .restricted to those values fn the plant Technica*1 Specifications. These restrktions are referr.ed to as the pool temperature*

1 imits. .... ~~-The magnitude of the SRV: discharge-related loads is. a function of the type* of 1C

..*discharge device used. In the past, straight~pipe, elbows, and 11 ramshead 11 * ,., n,*.
;. discharge devices have been used. Current practice calls for the* instanation'. *

of 11 quencher11 SRV discharge devi'ces, which are perforater p:ipe -s*ections.

The11 ** *

*, quencher* device has been found to reduce substantially the *hydrodynamfc discharg~

loads in comparison to those observed for the other discharge devices. The rT-quencher dfscharge device developed specifically _for the *i-tar'k I *torus

 ;,*conff guration* is shown in Figure 2. 3-1.

2. 4 Long--Term Program Task Des*cri pt ions In orde_r to assure the timely completion *of the LiP and provide an adequate basis for the evaluation of suppression pool* hydrodynamic* loads,* the.Mark r*

Owners Group divided the program _into a series of subtasks.' The task descrip-tions and or.ganization were presented to the staff in the 11 Marlc l Containment Program, Program Action Plan" (Refs.* 3, 4, 5, 6), as discussed in Section 1.3. A 1ist of. the LTP tasks *is presented in Table 2. 4-1. ,: The individual P,rogram tasks provided not only experimental and analytical bases for the development of suppression pool hydrodynamic loads, but also provided 17

10 In. DISCHARGE Pll'E MID-ARM SUPPORT

~::

14 In. PIPE SUl'POAT TORUS SHELL MITERED JOINT RING GIRDER Ffgure 2.3-i *Mark IT-quencher discharge device.

Table 2. 4-1 . Mark I Long-Term Program Tasks Task Numb@r . Task Oescriptio~ l.O Program Action Plan 2.0 Pre 1i mi nary "Load Eva 1uat ion 3.0 Structural Acceptance Criteria 4.0 Generic Structural Evaluation 5.0 Hydr.odynamic Load Evaluation_ I 5.1 Monticello In-Plant SRV Tests-5.1.1 SRV Ramshead Tests* 5.1.2 SRV T-Quencher Tests 5 .. 2 4T Condensation Tests 5.3 flexible Cylinder Tests 5.3.l Hydrodynamic Impact Tests 5.3.2 Cylinder Drop Tests ( 5.3.3 Pool Swell Impact Tests 5.4 Seismic Slosh Tests 5.5 1/4-Scale 2-0 Pool Swell Tests 1,:

5: 5.1 ..::'* Scaling Law Verification

5. 5.2

Download Oscillation Evaluation 5:s.3 .

LOR Plant-Unique Tests "I

                    'o~ I 5.6              !=             3-D Pool Swell Tests
                ** : i

5.6.l 1/12-Scale 3-D Tests 5.6.2 1/30-Scale 3~0 Tests 5.7 Initially Deleted 5.8 1/12-Scale 2-D Tests 5.9 Pool Swell Model Development 5.10 Miscellaneous Monitoring

s*.11 Full-Scale Test Facility . 5.12 '.Multivent Chugging Tests (Cancelled) 5.13 Chugging Analytical Evaluation 5.14 Submerged Structures Evaluation 19

Table. 2.4-1 (Continueij) Task Number Task Description

5.15 Structural Hydrodynamic. Interaction 5-.15.1 Interaction. *Analytical Evaluation 5.15.2 Interaction Test Support 5.16 Mark I Submergence Tests S.'16.1 Chuggi~g Submergence Tests 5.16.2 Chugging Mitigation Tests 5.17 Condensation Oscillation Evaluation 5.18 Multivent Interaction Test (.Cancelled) 6.0 Load Mitigation Development .

6.1 Chugging Mitigation 6.1.1 Chugging Parametric Sensitivity 6.1.2* Chugging Mitigation Tests (Cancelled) 6.2 SRV Mitigation 6.2.1 T-Quencher Development 6.2.2 Discharge Line Mitigation (Cancelled) 6.3 Pool Swell Mitigation 6.3.1 Pool Swell Screening Tests 6.3.2 1/4-Scale Mitigation Tests (Cancelled) 6.3.3 Vent Header Impact Mitigat-ion (Cancelled) 6.4

           "    Mitigation Requirement.s Assessment.

6.5 LOCA Mitigator Application Criteria (Cancelled) I-6.6 AP and Reduced Submergence FunctionaJ Assessment 7.0 Generic Load Definition Report 7.. 1 SRV Loads.Analytical Models

  *1.1.1        SRV Discharge Load Models 7.1.2      . SRV Di scharg~ Pipe Load Models

7.1.3 Multiple/Consecutive SRV Actuation Evaluation

   -7. 2        SRV Loads Applications Guide 7.3          LOCA Loads .

7.3.1 Drywell Pressurizati~n Model 7.3.2 LOCA Load Calculational Techniques

  .7.4          Load Combination Criteria and Methods 20

Table 2.4-1 (Continued) Task Number ,Task Description 7.4.1 Timing Bar Cha~ts 7.4.2 SRSS Load *combinations 7.5 SRV Discharge Steam Mixing Model 7.6 Load* Definition RepQrt - Preparation 21

scoping studies which were *used by the Mark I Owners Group to direct the course of the program. Consequently, *throughout the course of the LTP, task scopes were modified or tasks were cancelled on the basis of the results of . the Mark I Owners Group's "decision points. These decision points principally involved 11 1 . selecting options relative to structural modifications or load miti~ation. Periodic-meetings were held between the staff and the *Mark I Owners Group 'to* discuss preliminary task results and decision point conclu~ions. Most of the LTP tasks were directed toward the development of experimental and analytical information which could be used to develop generic suppression pooJ hydrodynamic load definition and assessment procedures. Other tasks provided. information concerning potential structural modifications and hydrodynamic load mitigation techniques which could be used to implement the program in the plant-. unique analyses. Through th~ decis~on points, four load mitigation techniques were dev~loped generically for application to the Mark I plants: (1) differential pressure control for LOCA loads., which is described in Section 3.12. 7; (2) reduced submergence for LOCA loads, described in Section 3.12.6; (3) the vent-header deflectors for the LOCA vent header impact loads, described in Section 3.5.2; a.nd {4) the T-quencher discharge device for SRV loads,' described in Section 3.10. When each Mark I licensee performs the LTP plant-unique analysis, the licensee's engineering group will select the optimum combination of structural modifications and/or load mitigation techniques by which.the originally intended design-safety margin for the containment structure will be restored.* The applicable results of the LTP tasks were s*ubmitted to the staff in a series of reports and are summarized in the LOR and the PUAAG. Specific rep9rts are referenced in the text of this evaluation. 22

3. HYDRODYNAMIC LOAD EVALUATION 3.1 Introduction The sections below present the staff 1 s eval~ation of the definition *proce*dures for suppression *pool hydrodynamic .loads *which were proposed by the Mark I Owners.

Group for use. in the LTP plant-unique analyses. In certain cases, the staff has concluded that the load*definitfon proce4ures as proposed. are unac~eptable .

 . For these cases, modifications and/or clarifications to the load definition techniques have been specified to ensure that a method acceptable to the NRC will be used in the plant*unique analyses. These requirements are presented in Appendix A and were originally transmitted. to each Mark I licensee ;n_
   *october 1979 to. begin implementation of this program. Jhe bases for these requirements are also presented in the followfog evaluation.

This evaluatfon and th~ plant*unique assessments are intended to address only . ... :-those events or event combinations wMch involve suppression pool hydrodynamic, _.loads. This evaluation includes certail'! loads in the e~ent combinations which***

   *Were reviewed and approved by the staff in. the Hnal Safety Analysis Report :*:.* .

I * . *

   .(FSAR) for each plant: However, these loads are discussed in this evaluation,:*

'because improved analysis techniques have evolved since the time the FSAR was.,*

* *reviewed. Unless otherwise specified, any loading condition or structural
  ,analysis technique not addressed by this evaluat'ion will be,in accordance with.
   .the p1ant's approved FSAR.

3. 2 Containment. *Response Models i i The drywell and suppression chamber transient-pressure-and-iemper~ture response to a LOCA are calculated by the GE Pressure-Suppression-Containment Analytical Model (Ref. 9). This ana lyt i_ca l. ~odel ca 1cul ates the thermodynamic response of the *drywell, vent system, and suppression chamber volumes to the mass and energy released from the prim~ry system following a.postulated LOCA.

For the design-basis accident (OBA) analysis, *the drywell is assumed to be at a.maximum operating temperature of 135°F and a relative humidity of 20 percent, 23

thie suppression cl')amber is assumed to be at the arithmetic mean of the m'aximum and minimum operating pool temperatures, with a relative humi'dity of 100 percent, and the pool level is assumed to be at. the maximum submergence of the downcomers * (minimum torus airspace volume). Condensation in the drywell is conservatively neglected, *and the vent system flow loss characteristics are maximized. The . mass and energy release into the containment from the primary system is calculated independently, as described in Section 3.2.3. A typical calculated DBA containment pressure response is shown in Figu_re 3:2-1. The assumed in_itial conditio~s will result in a conservative estimate of the. drywell pressure and pressurization rate following. a pqstul.ated LOCA. Because the analysis assumes. an average torus temperature which i.s conservative for vent system loads (see Section 3.3), the torus pres_sure*is stepped-up 1.0 psi before ~O seconds and 2.0 psi after 30 seconds to estimate the torus pressure respon~e for maximum pool temperat~re. These.analysis techni'ques have provided conservative estimates of the containment response to a LOCA, in comparison

                             .                                    - . CONTEMPT-LT with the results of . the staff's computer code. On this basis, the staff has concluded that the containment pressure and temperature analysis techniques are acceptable.

3. 2.1 Postulated Pipe* Breaks

The DBA for the Mark-I containment design is the instantaneous guillotine rupture of the largest pipe in the primary system (the recirculating line). This LOCA leads to a specific combination of dynamic,. quasi-static, and static loads in time. Howeve*r, the OBA does not represent the 1imiting case for all structural elements. Consequently, a spectrum of postulated pipe breaks must be investigated to determine the worst loading condition for each structura.l element. For the LTP, an intermed.iate *break accident (IBA) and a small break accident (SBA) have been specified, in addition to th~ DBA.

The IBA. is a 0.1 square foot instantaneous liquid-line break in the primary system. This break size will. not result in rapid reactor depressurization and, cons*equently; will not result in significant pool swell loads. However, this break size is large enough that the high pressure coolant injection (HPCI) cannot

                                     . 24

  &0----------------------

VENT ,CLEARING INVENTORY DEPI.E TION

        , ~ .eco_oLED FL UID DEPLETJ~N I                                 '"EAA UNCOVERV MESSUR.E EOUALlt ATION OAYWELL 20
                                                                                       'I,.

o------------------------ 0 10 TIME Al"TER tlllE AIC: INITIATION 20 la d Figure J.2-1* Typi cal Mark I OBA pr es su re response. 25

maintain the reactor vessel water level. Therefore, this LOCA will result in a combination of condensation loads and multiple SRV discharge loads. The SBA is a 0.01 square:..foot instant~neous ~team*line break if! the primary system.

The fluid loss rate for' this break size is large enough to depressurize the reactor vessel and small enough so that HPCI operation can maintain the reactor vessel water level.. Therefore, 'this LOCA will result 'in a long*duration comtiination (relative to the.OBA and IBA') of chuggin$J and multiple SRV discharge loads.

3*.2.2 Event Combinations and Timing Not all of the* suppression pool hydrodyn~mic loads discussed in this evaluation can occur at the same time. In addition, the load magnitudes and timing will vary, depending on the a~cident scenario under consideration. Theref~re, i.t is nec.essary to construct a series of event combinations which can be used to describe the circumstances under. which individual loads might combine *

.The event combinations proposed for the LTP are shown in Figure 3.2-:2: The combinations of lo~ding conditi.ons have been determined from typical plant primary

. system and contain~ent*response analyses, with considerations for autom~tic actuation, manual actuation, and single active failures of the various syste~s in eaah event. The magnitude and timing for each.loading condition,are discussed in the individual load evaluation.s in the following sections*. In gen~ral, the timing and duration of the Joads are determined as follows: (1) Containment response .<pressure, temperatur~,. anq reactiol")) is determined from the containment response analysis. (2) Poo 1 swe 11-re 1ated *1 oads are determined fro~ the sma 11-scale tests described. in Sectio'ns 3.4 through 3.7. (3) LOCA condensation loads are bounded on the basi*s of a typical plant containment response analysis, based on vent system flow. 26

SRV SBA SBA+ EQ SBA+SRV SBA+SRV+EQ

                           +                                                 DBA        DBA + EQ    DBA+SRV   DBA+SRV+EQ

. l SRV EQ IBA IBA+ EQ IBA+SRV IBA+SRV+EQ Ea,_rthquake Type 0 s 0 s 0 s 0 5 0 5 0 s 0 s 0 s 0 s 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 i7 18 19 20 21 22 23 24 25 26 27 LO.ADS Normal X X X X x- X X X X X X X X X X X X X X X X X X X X X X Earthquake X X X X X X X X X X X X X X X X x* X SRV Discharge X X X X X X X X X X X .x X X X LOCA Thermal X X X X X X X X .x X X X X X X X X X X X *x X X X LOCA Reactions X X X X X X X- X X X X X X X X X X X X *X X X X X LOCA Quasi-Static X X X X Pressure X X X X X X X X X X X X X X X X X X X X LOCA Pool Swell X X X X X X LOCA Condensation X X X X X X X X X X X X Oscillations LOCA Chugging X X X X X X X *X X X X X EQ = Earthquake Event SBA= Small*Break Accident 0 ~Operating-Basis.Earthquake IBA = Intermediate-Break Accident

s = s~fe-Shutdown Earthquake DBA = Design-Basis Accidf!nt SRV = Safety-Relief., Valve Discharge Efent "Figure 3.2-i Mark I event i;ombinations.

( 4) SRV discharge loads are based on a plant-unique primary system analysis. However, the duration of the SBA condensation loads proposed by the Mark I Owners Group is assumed to be .terminated by manual actuation of the "ADS 10 minutes

after the postulated pipe break. Each licensee or applicant m~st assure the limited duration of the SBA condensation loads by specifying procedures and primary system parameters that the operator will use to tern{inate the event (Appendix A, Section 2.1). Long *durations may be assumed for the SBA condensa-tion loads where specif;c plant procedures dictate such a change.
However, the staff assessment of the effects of pool thermal stratification (Section 3.12.6) and asymmetric. v*ent system flow (Section 3.12.3) was predicated on a 10-minute duration for the se*A condensation perfod.
Those licensees or applicants that select a longer period must assure that their procedures are adequate to preclude adverse consequences from the"Se effects.

The staff review of the proposed event combinations for the Mark* I LTP indicates that*the. load combinations, in conjunction with the* postulated accident scenarios and the proposed load definition techniques and, as modified by the acceptance

~riteri~ in Appen~ix A, will provide a conservative assessment of the acciden~

and normal transient loading conditions which could be impo~ed on the suppression chamber str~ctures. On- this basis, the pro.posed ev~nt combi nat f ons

are acceptab 1e.*

An additional evaluation concerning the application of the event combinations to determine the design service levels is presented in Section 4.3. 3.2.3 Containment Mass and Energy Release* The primary-system-break flpw rates are a principal input to the containment respons*e analysis." For th*e design-basis accident (OBA), the proposed mass* and

energy releas~ rates*from the primary system are to be calculated with the
homogeneous equilibrium model (HEM) (Ref. 10) applied in a nonmechanistic reactor system, which does not take ~redit for pressure reduction in the piping during the early portion of blowdown, and with*conservatively assumed liquid flow during most of the remainder of*the blowdown (Refs. 9, 11). The staff has compared the mass and energy release rate predictions of the GE model to those of a con~

servative RELAP-4 analysis, and has concluded that the GE model will provide a** 28

conservative estimate of the maximum mass and energy release rates for a postulated do.uble-ended recirculation line break in BWRs with a Mark I contain-ment system .. On this basis, th.e staff has further con.eluded' that application of the' HEM model for the .DBA containment response analys.is is acceptable .. A detailed evaluation of the HEM.model has been issued by the staff (Ref. 12) and is con~ained in a revision to the GE topical report (Ref .. 13). Thi]! staff has determined that the application of HEM to calculate the mass and energy release. rates from the primary system wi 11 not. necessarily provide con-servatively _high release rates for the IBA an~ the SBA due to the potential. break configurations. However, the purpose of the IBA and SBA is to provide a spe~trum of event combinations whe~e the primary loading conditions are steam condensation and SRV discharge loads. The primary loading condition affected by the HEM model is the CQntainment pressure and temperature response. For the IBA and SBA, the containment response is of secondary importance to the ... loading condition, and the primary loading conditions ar.e calculated inde- ~;;

. pendently of the results* of the containment response analysis., On thfs basis.r,*

application of the HEM model for the IBA and SBA event combinations is ~~ 1 acceptable. 3.3 Vent System Pressurization and Thrust Loads Reaction loads 9ccur on the vent system (main vent, vent header, and downcomers) following

       .       a LOCA because
                      .       of pressure imbalances between the increasing pressure

_in the event system and in the surrounding torus airspace and because of forces resulting from changes in flow direction. The load definition procedures pro-posed in Section 4.2.of the LOR are derived from the pressure' and flow. ~ransients

calculated by the GE containment response analysis. These l.oads are calculated only for the DBA, which provides a *more rapid pressurization rat:e and higher mass flow rate than either the ~BA or SBA. Horizontal and vertical force com-ponents are -calculated. at each location of a change -in flow direction.

Two different _sets of *equations to .calculate* the vent system loads are *provid~d ii:i the LOR. The fi.rst set, intended for use up to and_ including the time of downcomer clearing, assumes the*entire vent system (excluding the portion of the downcomers containing water) is at drywell pressure. 29

In order to determine the downcomer clearing time, the GE containment response mode 1 incorporates *a* *conservative vi rtua 1 mass, equi va 1ent to an extended down-comer *1ength of 2.25 feet for a 2-foot diameter downcomer. This was based on the Bodega Bay test facility (Ref. 9) which has a relatively small .ratio of pool area to vent area. Hydrodynamic theory indicates the virtual mass should decrease with an increasing pool area to vent area ratio. *A large virtual mass is conservative, since it leads to a later clearing time, with a correspondingly larger instantaneous difference between drywel) and torus pressures. Comparisons of the predicted d~wncomer clearing_ time with measured values for the Humboldt Bay test facility show that .the predicted clearing times are conservative (i.e., later), although the differences are. *smal 1. The second set of equations is applied starting at 200 milliseconds after downcomer. clearing, the set accounts for unbalanced pressure area terms and forces arising from changes in the dfrection of the flow momentum vector. The instantaneous vent system flow rate is calculated by the GE containment response analysis assuming homogeneous fl ow from the drywe l L The instantaneous pressures in the main vent, ring header, and downcomers are calculated assuming a con_serva-tive distribution of the flow resistance in the vent system*. The 200-millisecond

int:erval after downcomer clearing is intended-to be a relatively early estimate of the time of bubble breakthrough. While the LDR considers this conservative,

the method of anal_ysis does not include any water inertia effects after vent clearing, so that the assumed bubble breakthrough time ser.ves only as an initial time for applying the* steady-flow equations. Between downcomer clearing arid bubble breakthrough; the LOR proposed method of calculation assumes a linear variation in vent system thrust loads. Based on a review of the scaled pool swell data (Ref. 14), this procedure appears adequate for cases with zero initial drywell-torus pressure differential, since measured downcomer internal pressures.drop rapidly after downcomer clearing. This method for coupling the two sets of equations does not appear adequate, however, for plants with a large initial drywell-torus pressure differential. For these cases, downcomer clearing occurs at earlier times and at lower .dr~ell pressure values than for plants with zero pressure differential, and the difference between vent system internal pressure and torus airspace*pressure ca~ jncrease after I J 30,

vent clearing. This effect has been observed. in several ~f the scaled pool swell tests (Ref. 14.). Also, it should be noted that when the drop in internal press~re* after downcomer c.learing occurs, it starts at the downcomer end of the vent system: We would expect the vent header and main vent to approach* steady- state values at even later times.

The delayed drop in vent system internal pressures can result in peak thrust loads on*the.vent system which.

exceed th~se at the time of "downcomer clearing and subsequent bubble breakthrough . 0

         .Conseq_uently ,* the* sta ff has ~eq~i~ed (.Appendi)( A, Section 2. 2) that the down-comer clearing transition time for plants that use an initial drywell*torus pressure diffeJ'ential be calculated assuming iero pressure* differential *. For those plants.with an initial pressure differential, the. ~rit~ri~ discussed 'above
         . regard.ing the time of downcomer clearing wn 1 assure a conservative transition *
        . to .the steady-flow regime.

Based on the.assessment.above,, the staff h~s concluded* that_the proposed method, ... 1., as modified by the acceptance criteria in Appendix A, will prov*ide a conserva-tive estimate of the vent system pressuri.zation and thrust loads and is, ;.! therefore, a~ceptable. : 3.4

Torus Pool Swell Pressur.e Loads

   *.      In the event of a postulated design-basis accident (OBA), as described in*

Section 2.2.1, the drywell and vent system would be pressurized, causing the I . * -. water leg ini:tially in the downcomers to be accelerated downward into the suppression pool. Immediately following downcomer clearing,_ air bubbles form at the exit of the downcomers. As these bubbles form, their presence. is felt

          .                                                    .                 )

on the submerged portion of the torus walls as an increase i-n pressure~ Con-sequently, the torus will experience a dynamic . net. .downward load as *the bubble, pressure (which at the time of the downcomer clearing is approximately equal to drywell pressure) is transmitted through the suppressiQn pooL At that time, the torus airspace has not yet sensed the effects of the transient. The ~ir. bubbles continue to expand and decompress,'* causing a ligament .of solid water above the bubbles* to be accelerated upward. As the water slug continues to ri.se, the wetwe 11 airspace vo 1unie above the water in the torus is compressed. resul~ing in* a ,dynamic ,net upward load on the torus. The pool swell' continues until there is'a breakup of the water ligament, and direct communication between the bubble and airspace is achieved. 31

From the testing.done during the STP, the phenomena described above have been shown to be sensitive to various plant parameters, such as downcomer submergence and drywell-to-torus differential pressure .CSection*3.12.7). Consequently, the Mark I Owners Group devised a testing program for the LTP whereby the pool s~ell loads could be assessed on a plant-specific basis. The Quarter-Scale Test Faci 1i ty (QSTF) *was used for this task. The QSTF was designed so that _the torus sector width, grywell volume, downcomer system configuration, vent system resistance, vent header deflector, and other test conditions could be varied on a plant-specific basis (Ref. 14). The data obtained from the QSTF plant-unique tests serve as the principal source for the pool swell load specifi-cations *for the LTP. Although the QSTF. is nominally one-quarter scale, the plant-specific scaling factor wi*ll vary slightly based on a fixed torus diameter, with all other geometr.ical P.arameters scaled accordingly. The scaling relationships for the pool Sl,(lel l tests were developed during the STP based on the method of similitude. This technique involved the formulation of the governing conservation equation~, boundary conditions*, and foiti al con-ditions for each of three regions, i.e., an air bubble in a pool, the pool water, and a trapped air spac~ above the pool. The equations and boundary conditions are then nondimensionalized, which results in similarity parameters appearing as coefficients. The significant scaling parameters, selected* on the basis of their relative order of-magnitude, are retained from the analysis. The.following scaling relationships evolved for typical Mark I conditions: Pf = p 5 C'Lt1L 5 ) tf = ts (Lt'Ls)~

r (mh)f = (mh)s (Lf/Ls)7/2 where t~e subscripts f ands refer to the full-scale and small-scale systems, respectively,* and p = pressure t = time m=mass flow rate into the bubble h = enthalpy of the mass flow L = characteristic dim~nsion {e.g., torus diameter).

32

These general scaling relationships for pool swell were confirmed by comparisons' of the.1/12-scale test results from the. STP and QSTF test results for matched

   . test conditions (Ref. 15) within the uncertainty Hmits of the test data. In add;.tion, is:idependent research st.udies performed for the NRC by the Massachusetts.

Institut~ of Technology (Ref. 16), the Lawrence Livermore Laboratory (Ref. 17),

   . and the University of Californfa at Los Angeles (Ref. 18) have also confirmed, these general poo.l swell scaling relationsMps. However, during our review of the poo 1* swell data., base, we found that errors can be introduced by the met~od ..

used tp establish the enthalpy flow into the bubble (mh). The enthalpy flow scaling is an approximation, because exact scaling of the flow into the bubble cannot be pr~ctically achieved in the small-scale models. The method commonly used to scale the e'nthalpy flow involves the use of orifices to increas_e the flow* resistance. Through comparisons of data from the various pool swell tests (Table 3.4-1), the relative locaticm of the orifices *and the;!

.. te,ehniques used to establish the 3-D downcomer orifice she distributi'on .were found to haye a significant effec.t on the net torus vertfoal pressure -load~*

This effect has -been considered in the QSTF plant-unique tests, and the -=*. uncertainties associated with enthalpy fl OW* sea 1ing have been inc 1uded in ou*r review of tho~e tests* (de~cribed in Section 3.4.1).. . Another uncertainty associated with flow sea-ling concerns the effects of compres-sibil~ty of the flowing medium.:* Acoust-ic waves tr~vel back. and for.th through*. the vent system during the downcomer clearing process. These waves cannot be accurately scaled, and their presence is further masked in the scaled pool swell tests by the flow oriffces. The effect of these waves is*to cat.is~ an increase

    *or decrease in the.pressure at the down~omer exit at the time of downcomer clearing.

Based on preliminary calculations performed by EPRI and GE; th~ staff has deter-mined that these e"ffects are sma,11 in comparison to other. uncertainties_ -identified in Sec~ion 3.4.l~ On this basis, the staff has conclu~~d that implementation* .. of the. LTP should.continue wtt'ile the Mark I Owners Group continues its assessment of compressibility effects. As described in Appendix A, Section. 2.5, the staff* has required that the Mark I Owners Group complete this assessment and justify the adequacy of the affected load specifications. The staff will report the results of *its evaluatio~ in a supplement to this report . . 33

Table 3.4-1 Mark I Pool Swell Test Programs Nu!llber Facility Scale Sector of Tests GE (STP) 1/12 2-D 110 GE (LTP) 1/4* 2-0 324 EPRI/SRI 1/11. 7 3-D 68 Livermore 1/5 2-D/3-D 27

Scale varies slightly for plant-unique tests.

3.4.l Net Torus Vertical Pressure.Load The net torus vertical pressure load is equal in magnitude to the net dynamic force acting on*the torus divided by the pro3ected torus cross-sectional area. A typical vertical load pressure transient is shown in Figure S.4-1. As previously discussed, the net torus v~rt i ca 1 load spec.ifications

proposed by the Mark I Owners Group for the LTP are derived from a series of QSTF plant-specific tests (Ref. 14) (with a minimum of four test runs per plant design).

The Mark I Own~rs Group furth~r proposed that the mean (average) loads from these tests should be used for the LTP structural assessment. 0 The testing procedures. adopted iR the plant-unique test program incorporated. methods to ensure that a conservative loading condition was obtained. The more significant items include: (1) Th~ calculated.drywell pressure history was used as a lower bound for the test drywell pressurization history. (2) QSTF tests were performed at the minimum plant operating ~P and maximum downcomer submergence for the plant. 34

B PEAIC Ul"LOAD 4

   .J Ill Ill 0

ZERO a: A, UPLOAD ,r-

         .                                                                                              /'

PEAK DOWNLOAD

        .,2 ................................................................................................................ 1&CIO
                                                                                                                            ~

0 200 . 400 IOO IOO 1IXIII 1200 1400 TIME A"ER BREAIC INITIATION l,_I f;gure 3.4-l Mark I torus vertical pressure transient. r 35

( 3) The vent fl ow resistance was decreased to account for the fact that the initial air temperature in the drywell for the QSTF tests was 70° F, whereas the maxfmum. plant drywell operating temperature is

135° F. .

A margin Qf conservatism which will vary on a plant-specific basis is inherent

in *the above ite~s. especially in the test drywell pressurization history.,

Ori the basis of the staff review, the proposed load definition methods presented

.-in Section 4. 3.1* of the LOR a~e unacceptable in their present form. The areas in which the staff finds the.procedures deficient concern the use of the mean ..

values fo~ the load specification and .the data base used to ass~ss the potential for three-dimensional pool .swell effects. Based on a number of conservati~m.s inherent in the load Qefinition, the direct use: of the mean va*lues determined in the QSTF has been deemed appropriate in the* lDR~ .Although*that ther~ are conservatisms in the load definition, the use of the.mean loading function without taking into account the stati~tical variance of the measuremeijts is not acceptable. This conclusion was reached because the conservatisms are plant-specit:_ic and thei.have not been.quantified. Therefore, the* acceptance criteria (Appendix A, Section 2.3) includes margins to be applied*to the *net vertical pressure loads, which are.expressed in terms

Of p~unds*force at the scaled test condition. These margins were. derived from a statistica.l analysf.s o.f the**QSTF data base (Ref.* 19), and .they: represent an estimate of the standard devi.atfon in the pea~ loads. For the downward pressure loads, the variance was found to be a function of the lo*ad magnitude and has been expressed as a quadratic function of the peak downward load (i.e.,

Q., 00002 times the square of the QSTF m_ean peak downward load). For the upward .pressure lo.ads, the variance was found to be approximately linear with load magnitude; therefore, a. constant percentage margin has been. specified (i.e., 6.5 p~rcent). An additional margin on the upward load has been specified for the reasons described below. The.QSTF is a two-dimensional (2-D) test*.facility; i.e., it consists of a single pair of downcomers with a cell .width equal to the average downcomer spacing. 36

However." in the actual plant t~e downco~ers are irregu*larly spaced a.long the axis of the torus. In order to asses~ three-dimensi~n~l _(3-0) pool swel~ effects, the* Mark I Owners Group sponsored a separate testing.program, which was conducted

 . by the Electric Power Res~arch Institute (EPRI). The EPRI, tes.t facility was a 1/12-scale, straight cylinder e~uivalent of a 90° torus sector, containing 2.

main vents and 12 downcomer pairs prototypi_cally spaced {Ref. 20). The Mark I Owners Group assessed 3-0 effects by directly comparing .QSTF data and EPRI data for similar test conditions (Ref. 21). The . QSTF test series and the EPRl faciJity both modelled the Browns Ferry plant geometry, and the compariso~s were made. at conditions of full ap and 3-foot, *4-inch submergence. On the basis of its review, the staff has concluded the QSTF/EPRI data comparison does not adequately assess the potential for 3-D effects. This conclusion was based prindpa.lly

on the fo 11 owing observations: '

(1) The EPRI test.s used in the comparison were conducted at higher values of *

r flow. resistance than we*re the QSTF tests. As a result; the ,EPRI uploads.' ..

are lower than would have been obtained if .the flow resistances were. properly matched. :*. (2) The Browns Ferry geometry is not pro~otypical of the majority of Mark 1*. plants. In fact, the 45° downcomer configuration has been .found to cause early breakthrough, .thereby reducing .*m~ximum torus airspace compress-ion. ' (3) . The data used for the coii1parisor;i were obtained using orifices located* in

                                . its studies~

the downcomers *.. F.rom . the staff has concluded that an exaggerated pool surface c~rvature resulted from the use of downcomer orifices in these tests .

. (4) rhe-use of. full Ap and reduced submergen~e as test conditions for the QSTF/EPRI comparison te~ds to minimize poo 1 swe 11 *effects*; .Tilus; .~he staff would not* e~pect to bound a 3-D effect at these conditions~

To establish bounds .on the potential for the 3-D pool swell effects, the staff turned to a confirmatory* data b.ase provided by the Lawrence Livermore *Laboratory (LLL) C Ref. 17). The LLL test program ~as*conducted .for the NRC_to proviqe 37

confirmatory pool swell test data. The test facility consisted of 1/5-scale 90~ (3-D) and- 7._5° ,(2-0) torus sectors I modeled after the Peach Bottom plant geo111etry. The test data from this facility have gel)erally confirmed t_he basic hydrodynamic phenomena-~bserved in the testing programs conducted by the Mark I Owners Group; however, the peak upward pressure loads in the 3-0 sector .were consistently higher than those in the 2-D sector. Based on its review of the LLL test data, the staff has found . . that a part of.. the difference is the result of a mismatch in the modeling of the. 3-D and 2-D sectors. The mi~match resulted from differences in the sizing and location of the fl,ow-:scaling orifices in the two LLL sectors .. .The ~taff concluded that the location of the flow scaling orifices in the main vents, coupled with the effects*of the tested geometry and initial conditions, provided a conservative assessment of the potential 3-D pool swell effects. However, the .st.a ff has performed an analysis of the LLL. facility geometry in ord_er to extract. the differences that result from the mismatch in flow scaling. A one-dimensional transient pool swell analysis was performed for both the Livermore 2-D and 3-D _sectors. The system as modeled con$isted of drywell volume, ven~ line volumes *upstream and downstream of the orifice, header volume, 'downcomer vo 1ume, 1i quid s 1ug I an!i torus_ airs pace vo 1ume. Maxi mum va 1ues of up 1oad pres sure . were determined.by co"}puter analysis for both the 3-D and 2*0 sectors.for initial drywell pressurizatio~: rates ranging from 40 to BO psi per second. The results of these calculations have demonstr~ted-that . th~ LLL sectors were mismatched as a result of differences* ,in vent system capacitance (volume) and flow resistance. I o * ' The effect on peak UP,} oad pressures varied from 3 percent to 9 percent over the range o*f pressurization rates considered in the study. After adjusting the LLL .experimentally observed upload ratios to accourt for these findings, the staff was able to estimate*a margin to bound the uncer~ainties arising o *

I o from t~e comparison of all the two-dimensional and three-dimensional upload test data. For completene~s, it should be stated here that similar download comparisons were made and were found to exhibit excellent agreement. There-fore, no addit_ional margin is neces~ary to account for the possibi.lity of a 3-D/2-D effett on the torus downloads obtained in the QSTF *.

38

Based on this assessment, the staff has concluded that a margin of is percent applied to upward ve~tical pressure loads derived from a 2-D testing program will provide* a conservative estimate of the upward loads resulting from a* design-basis LOCA. This margin. coupled with the*margins for ~ncertainty previously described, forms the requirements presented in Appendix A, Section 2.3. As previously discussed, the QSTF tests were conservatively performed; the degree of conservatism could be established on *a plant-specific basis~ To avoid penalizing specific plants whose tests were overly conservathe, the* staff requirements permit the margins specified above to be reduced or omitted where offsetting conservatisms in the tested conditions can* be quantHied. These conservatisms are to be established using sensitivity parameters f~om

 . the generic series of QSTF tests (Ref. 22). Conservatisms will be retained in the load specification by using minimum parameter deviations from the nomi~al ,.

plant conditions. For those plants that propose Ap operation for the LTP, an additional stru~tural analysis is required assum.ing a loss of *the Ap, as desc.ribeci in Sections 3:*12. 7 and 4.3.3. For this analysis,* the staff has concluded that a single *plant-specific QSTF test run is sufficient for the purpose of_ the analysis, provided

I
that the downward and upward loads are increased by the margins established for the base-case analysis at the normal piant operating conditions.

                              '      .             .            ~
 .During the STP, an issue relating to .the net torus vertical pressure loads was identified which con.cerned an anomaly in the downward load observed ii"! the

) 1/12-scale test results. The peak downward load~ from the.january 1976

1/12-scale test series were approxima.tely 33 percent higher than those from the December 1975 test series for similar test conditions.' To ascertain the cause of this anomaly, the Hark I Owners Group conducted an additional.

1/12-scale test program as part of the LTP (Ref. 23).' From these tests, they determined that the 1oad i nc"rease was caused by a flexing of the test *faci 1i ty sidewalls.

A-similar testing program was conduc;:ted *with the QSTF (Ref. 24),

from which a method of reinforcing the sidewalls of the-test facility was devised.

                                       * . 39

This reinforcing w,s used in all of the QSTF plant-unique tests for the LTP. The staff concurs with*the Mark I Owners Group assessment and corrective action and concludes that this issue has been adequately resolved.* In summary, the staff has concluded that the application of the QSTF plant-specific tests, as described in Section 4.3.1 of the LOR and as modified by the margins set forth in Appendix A, Section 2.3, will provide conservative estimates of the net torus vertical P!essure loads resultin~ from a_design-basis LOCA.

3.4.2 Torus Pressur.e Load Distribution The spatial distributiQn of the pressu.re on the torus shell during pool swell, as proposed in Section 4.3.2 of the LDR, consists of the following

                                                                     . elements:

(i) An average submerged-pressure history on the torus shell derived from the QSTF plant-specific tests. (2)* A table.of multipliers which account for the variation of the average sub-

       !"erged transhnt pressure at different positions on the shell, derived from the EP~I l/12;scale 3-dimensional tests for axial .variation and QSTF tests for circumferential variation.

(3) A pressure transient in the.torus airspace region; derived from the QSTF plant-specific tests. The aver.age submerged-pressure _transi-ent is defined as .the net force applied to the submerge_d portion of the torus divided by the toru*s horizontal cross-sectional area. The average submerged-pressure history and torus airspace-pressure h.htory are derived from the torus shell pressure transients measured .., . fo the QSTF plant-:specif.ic test *series .. In al 1 of t.he transients, the initi~l conditions have. been extracted sb that only the dynamic partier of the tran-sients is presented. Therefore, care must.be taken to assure that the appro-I priat_~ P,lant-specific value_s of initial torus airspace pressure and hydrostatic I head are incorporated into the pressure definition. The transients which cor-respond to normal plant operating conditions represent means (averages) of the multiple QSTF test~ performed at this condition .

                     .                  40

                                      . . variation of the average submerged pressure, In order to account for the spatial multipliers "are specified at pertinent times'. throughout the pooi ..s~ell transi~nt at various longitudinal and azimuthal locations on the torus. The multipliers prese~ted in Table 4.3.2-1 o_f the LDR are given as a function. of time and a nondimensional position on the torus shell. Since the downcomer spacing is approxi~ately the same in all Mark l plants, it has been assumed in the LOR that the multipliers are applicable to all plants. The variations in the torus circumferential or aximuthal direction is based on an arithmetic mean of 44 tests performed in QSTF. The multipliers are.specified at 11 angular positions around the torus circumference*, ranging from 1bottom dead center to 90° ab9ve bottom dead.center, with symmetry being assumed. The longitudinal pressure multipliers we*re obtained in a similar manner from the pressure measurements in a u_nit cell

'-- of the EPRI 1/12-scale model (Ref .. 20). * *The uriit cell extends from the main vent* centerline plane to the adjacent nonvent bay midplane. The arithmetic mean of 24 EPRI tests was u*sed to obtain the multipliers for each locatio11, at

~*. the times of interest during the pool swell~ At points on t,he torus sh.ell; between those where the multipliers are.defined, linear interpolation has been proposed.

     ~s a result of its review of the applicable pool swell test data, the staff has found ttiat the proposed methods should .provide a reasonable def.inition of the distribution. However, to incorporate a margin for uncertainty, the staff requirements (Appendix A, Section 2.4) specify that the ....local pressure distribu-ti~n fs to be increased by the pressure-equivalent margins specified for the net torus vertical pressure load, so that the margin on the downward load is applied to the average submerged pressure transient and the ~argin on the upward 1oad is applied to the torus airspace tran~ i ent. The s.taff' has. cone 1uded that this technique wil~ provide a reasonably conservative ~orus local pressure definition, especially since the torus structural respons~ i~ more sensitive to the total applied load, rather than the load distribution.

3.5 Pool Swell impact and Drag Loads Impact load~ are a consequence of pool swel 1. As .the suppression pool surf~ce rises, any structures or components located above the pool {but lower than the 41

maximum elevation of the pool surface achieve~ during pool swell) will be sub-jected to water impact loads followed by a drag load until the upward motion of the pool stops. The principal structures which experience impact and drag loads during pool swell in a Mark I containment system are the vent system, the vent header deflector (if installed), and miscellaneous structural elements (e.g., pipes, beams, and gratings). In general, the load definition techniques proposed in the LOR.are based on.data from the QSTF plant-specific test *series. The specific load definition techniques for each of the principal structural gro1:1ps described above are presented in the evaluations belo'.". The impact and drag ~oading tra*nsient consists of an initial impact spike, which is caused by:water striking and wetting the lower surface of the structure, followed by a transition to a drag force, which is composed of a "steady-flow dr:ag 11 component ~nd an 11 unsteady*flow drag 11 component. (The latter is a result of the acceleration or deceleration of the flow field around the structure,) The specific loading transient is*a function of the geometry of "the ~ffected structure and the velocity and curvature of the pool surface at the t*im~ of impact.* 3.5.l Vent System Impact and Drag 3.5.1.1 Vent Header The LDR spec:i fication of_ the vent header impact load is based directly on QSTF data. The load definition consists of:* (1) the experimental data of local vent .header p.ressure in each of the Marl( I plants obtained from t~e QSTF plant-unique tests; (2) the specification: for each Mark I plant. of the pressure inside the vent header relative to that in the torus airspace at the time'of water impact on .the vent header, determined from the QSTF plant-unique tests; and (3) the pl_ant*unique header impact timing, i.e., longitudinal and circumferen-tial time delays, based on t~e EPRI three-dimensional pooJ swell tests and the QSTF generic test series, respectively .. 42

The load specificatio.n is presented in terms of the differential. pressure* acting on the shell of the vent header,.as measured in the QSTF plant-unique tests.

I
The staff has concluded that the QSTF tests will provide a reasonably conservative

. estimate of this loading function and are, therefore, acceptable., However, the longitudinal impact."timing defined in the LDR may not be sufficiently conservative. The longitudinal variation in the vent header impact load proposed in the LOR

 *is bas~d on an average of the header impact timil'!Q observed in the EPRI main-vent~

orifice and downcomer-orifice three-dimensjonal pool_ swel 1 tests. The orifices were introduced to provide the proper flow scaling (as described in Section 3 ..4). The longitudinal header impa_ct timing observed in the main-vent-orifice and downcomer-orifice tests were substantially different. In addition; the downcomer orifices in .the EPRI tests were varied in. s.i ze from <1owncomer tc, d9wncomer to match the full-scale . flow distribution which would . re~uit from steady-flow. .. condi-tions with a uniform backpressure. Additional EPRI tests were conducted with.split orificiesi i.e .. , with ha.lf J.he . resistance in the main vent and half in the downcomers. A similar downcomer* orifice size distribution was used. The header impact* ti.ming observed in these tests was very close to that observed in the_ downcomer-orifice tests. From these data, the Mark l Owners Group concluded that. the average of the impact

timing from the main-vent-orifice and downcomer-orifice tests will provide a conservative assessment of the loading ~ondition, because the main v~nt orifices allowed the fl~w through the downcomers to equalize, causing an atypically flat pool surface.

Based on its review of the te.st data, the staff has determined that the assumptions used to establish the downcomer orifice size distribution may not have resulted in a sufficiently prototypical flow distribution during the transient flow con-ditions that actually.prevailed. From analyses of the flow resistance distribution in the* dowricom*er**orifice-and_ split-orifice tests (a~ compared to the resist- * ~ ance distri~ution. in' a full-scale plant), .the staff has concluded that the flow di.stribution achieved in the main-vent-orifice tests may have been closer to

the prototypical conditions. Nevertheless, the *main-vent-orifice tests were resP.ect to the longitudinal header impact ttming

 -certainly conservative with  .                                            .       '

43

(i.e., longitudinal variation of the pool surface velocity as compared. to the average). Consequen~~y, the staff_ has required that the longitudinal variation in the impact. loads be derived from the EPRI 11 main vent orifice" tests, as described in Appendix A, Section 2. i:" !~e use _of _these* test data. in a manner consistent with that proposed by t-he Mark I Owners Group will provide sufficiently conservative loads to offset.

*any uncertainty associated with flow distribution effects on the pool swell longitudinal v~r~ation.

3.5.1.2 Oowncomers The LOR specifies th,e impact load on the projected surface. of the downcomers as 8 psid to be applied uniformly over the bottom 50° of the angled portion of the downco_me_r. starting when the rising pool *reaches the lower _end of the angled portion and ending at the time of maximum pool swell height~ The pressure is to be appli°ed perpendicular to the . local downcomer surface. This specification is based on plant-specific measurements in the QSTF facility and bounds the loads observed for all plants. The stafr':finds ~he proposed load specification acceptable, with the proviso that the s~ructural analysis.of the downcomer shall be dynamic, accounting for the approximate virtual mass of the water ne~r the submerged parts of the downco.mer, or a dynamic load factor of 2 sha 11 be app 1ied.

3. s. i. 3 Main**vent The impac~ load specification for the main vent proposed _in the LOR is based on the impact and drag load specification for general cylindrical structures.

as described in.Section 3.5.3. In.general, this approach is acceptable. However, the staff has developed spe~ific requ*irements for the main vent impact loads (Appendix A, Section 2.6.3) which will-ensure a sufficient level of detail in th_e loading transient and will provide consistency with the impact loads for other cylindrica~ structures. The.staff has*concluded.that the proposed pro-cedures, as modified by the criteria is Appendix A, will provide a conservative estimate of the transient impact load on the main vent. 44

.3.5.2 Vent Header Deflector Impact and.Drag In some Mark .I containment systems, deflectors will be installed below the vent header to shield the h~ader from the rising pool -s~rfac~ and reduce the impact load. on the header itself. Four deflector designs are under ~onsideration; they are identified as Types 1 to 4 in Figure 3.5-1.. Two methods to define the impact arid drag loads on the deflector were .proposed in*.the

                                                                . LOR and. are evaluated separately below. -When a vent header deflector i~ used, there is still an impact and drag*loading condition on the vent header. The header.

impact and .drag loads for . either of the deflector load definition techniques described below are defined by the methods described in Section 3.5.1.

3.5.2.1 Alternative A The LOR has proposed that specific Mark I plants *may choose to use scaled-up deflector impact and drag force hi stories from* the QSTF plant-unique tests.

This technique is applicable only where deflector force transients. were measured in the QSTF*plant-specific tests.

                                                                               "'*i*
*On the basis of its review of the ~caling relationships (discussed in Sectio'n 3.4)-

and the QSTF plant-unique test s_eries, the staff has concluded that this approach will provide a conservative* estimate of the deflector force ~ransients, with the fo 11 owing correct ions and c 1ari-ficat ions:

(1)

The QSTF deflector load measurement does not alway~ respond fast enough to resolve the initial impact pressure spike for the deflector Types 1-3.

Consequently, the loading tr~nsient must be adjusted to include the empirical vertical forte history of the spike shown in . Figure 2.10-1 of Appendb A. This empirical force hi.story has been derived from impact tests of cylinders conducted by EPRI (Ref. 35). Based on our review of

impact forces on wedges~ we conclude that this adjustment is not necessary for the Type 4 deflector.

(2) *The QSTF plant-unique loads must be adjusted to account for the effects* of impact time delays and pool swell velocity and accelera~ion differences 45

Vent Header Oowncomer' 0 Type 1 - Pipe 0 Type 2 ~ Pipe w1th angles Type 3 - Pipe with tees V

Type 4 - Wedge Figure 3.5-1 Mark I vent-header deflector designs.

46

which r.esult ifrom 'the uneven s_pacing *of the downcomer' pairs. The longi-

tudinal variatio~ iQ the deflector* force transient {i.e., sweep time)

      *must                                                           ,

be ba~ed on the EPRI main-vent-orifi.ce tests, for the reasons described in Section 3.5.1. (3) In applyfog the load to the deflector *. the inerti_a due to the ad~ed mass of wate_r. impacting the* deflector must be accounted for in the structura.l assessment of the deflector and its supports. These corrections and c:lari-ficatons are set forth as. requirements in Section, 2, 10. l of Appendix A. 3.5.2.2 Alternative B . . For those Mark I plants for which the vent header deflector has not*been tested via plant-specific QSTF simulations. the LOR specifies that a semi~empirical . appr:oach can be taken. where the. load is a superposition of (1)_ an impact transient; (2) a 11 steady 11 drag, and (3) an acceleration drag (Ref. 26). The LOR specifies certain empirical expressions for each of the three contributions. Both the .local, instantaneous . . pool velocity and pool acceleration are needed to evaluate the empirical expressions for the load and:are* to be inferred from I plant-specific QSTF tests. The staff finds the proposed semi-empirical load definition,.technique . . unaccept* able_because the 11 ste~dy 11 _dr~g contribution for the cylindrical (Type 1) deflector is not conser*vative with respect to the applkable test data and because an appropriate force ~ransient for the wedge-shaped parts of deflector Types 2-4 . has n~t _been specified. The Mark I Owners.Group has concluded that the propose~ specification_is validated by the fact that it conservatively predicts the vent header deflector loads for those cases that have been tested in the QSTF. The staff does not accept this claim because (1) comparisons have been done only. for some cases, (2) the degree or the conservat hm fo the coinpari sons varies from case to case,

                .        and (3) the source' of the conservatism is not clear. Because all of the essential ingredients in the proposed analysis technique have* not 47

been established to be correct or conservative, ttie staff is not confident that the model wi)l yield acceptable results in alJ cases. Cpns~quently~ t~e staff has specified requirements (Appendix A, Section 2.10-.2) that modify the proposed load definition technique to assure that a conservative estimate.of the deflector force transient will be achieved in all cases. These requirements principally involve a redefi'nition of th~ drag coefficient expressed as a_dimensionless force-time history (as shown in Figures 2.10-2 through 2.10-s in Appendix A). These fjgures ha~e been modified _from those originally trans-mitted_ to ~he Mark I Owners Gr.oup, based on a clarification of the geometri.es of the deflector designs and a reinterpretation of the data base for the drag coefficient following impact for cyHndrical s~ructures. For deflector designs that do not exactly match those shown in Figures 2.10-3 through *2.10-s in Appendii A, but which differ slightly in either the ~edge angle or the ratio w/d, the impact and_ steady drag correlation should be based on Wagner 1 s force hi.story for a wedge (Ref. 27) ana on th.e final steady-state drag, following tKe basic method described above.

 ~he initial impact transient for the cy~indrical portions of deflec~or Types 1-3 (as s.hown ~h Figures 2.10-2 through 2.10-4 of Appendix A) has been derived from*

EPRl impact data (Re~. 25). -The steady drag component for a *cylinder (Appendix A, Figure*2:10-20)

            *. I is based ort the estimated  values at which the EPRI impact load measurements leveled out. In Appendix A, Figure 2.10-2b, only the l~rge-cylinder

=EPRI tJata have been used, because the.small-cylinder data w*ere less complete .. Also; the assumption *;s made that the drag is largely independent of Reynolds number (at supercritical _Reynolds numbers); hence, the dimensionless drag depends _only on FrQude n~mber. This correlatian further recognizes that. in the limit of large Froude number, the drag for this case, with an open wake at torus air- . space pressure, must.* approach th.e value it would h.ave in a cavitating flow with a cavitation number of* zero, c = O. s* (Re*f. 28) .. 0 Figure 2.10-5 of Appendi><; A shows the impact transient for the Type 4 deflector, which is a simple wedge with a. 45° deadrise angle. The. impact transients of wedges have been studie"d extensively in order to understand the loads on seaplane 48

floats during landing. The first analysis w~s presented by Von Karman in 1929 {Ref. 29). Von Karman used a simple es~imate for the virtuaJ mass of ~he wa~er during impact and obtained a relation which, for the case of constant-velocity vertical penetration, may be expressed as ;. ( F = np V2 (cot p) x where F = instantaneous vertically_ upward force (lbf)

p. =water.density (slug/ft3)

V = water velocity (ft/sec) p = angle of wedge s~rfaces with respect to horizontal (deadrise an~le)

        . and x =::Vt cot p
 *js the instantaneous elevatio,n of the water surface, far from    .

the wedge,. relati:ve .;r.i*~ to the wedge tip, wit-ht the tim~ from the instant of first impact on the wedge

 . tip. .
                                                                      ,'i                         *ll :

H':

    ~oon thereafter; Wagner (Ref. 30) dev~loped his first _rough ,approxi!"atio~ for J*.

f, which differed from the equation for . F above only in that,,: it was higher

                                                                                  ..          by. ...
   *a factor of (n/2) 2

By 1932, however, Wagner had published° a much more careful...

                                    ,                         '        I    *        ;    ."*  ,,        *
  =and elaborate analysis (Ref. 27), and-on this basis he sugg~s~ed the formula ..
                                                                    . :i*         ,1 F= f pV2 ,~~ ~ .1]2 .* (2    t!n @)2 .{cot p)x*

1 where x is given as above and p is in radians. This relatioh*, wh*ich is *not-ah analytic solution for :F, was merely sug*gested by *wagner as a**correlation equation which accurately predicted botti his analytical solutio~s for:'p *.. O*and p .:. n/2,

as well as h:is numerical solution for one point in between, at p = 18°~
Note *
that at p = 45°, the case of interest in our present context; both Von Karman~s~*

and Wagn~r's relations for F yield exactly the same results. Wagner's expression has *rece;vei:f confirmation in the almost five* d_ec~des *since its publication, both from experiments (provided p is* not: too** c*lose* "to**o), as 49

well as from other theoretical studies (Refs. 31,32,33,34,35). Consequently, the force-time histor.ies shown in Figures 2. i0-3 through 2.10-5 of. Appendix A are based.on the assumption that Wagner's expression applies to the 45° deadrise angle wedges, with x measured ~rom the point of the w~d~e ~ip (projecte~ or actual) up to the time the undisturbed water surface would reach the top of the wedge. In Figures 2.10-3 and 2.10-4 in Appendix A, which apply to deflectors with a circular leading edge, the cylinder impact transient of Figure 2.10-1, based on the EPRI data-previously described, _has been added. Furthermore, it has been assumed that after the water level passes the elevation of the top of the wedge, the force drops, in a time corresponding to ha.lf the time it takes .the water to envelop the wedge, to 'a steady-drag value which corresponds to the case of a 45° half-angle wedge in a flow with cavi-tation number equ~l to zero (Ref. 30). The latter flow field is the same, at least at.large Froude numbers, as when there is an open wake cavity. The force transients shown in I

Figures 2.10-3 through 2.10-5 should be accurate (in the absence of pool acceleration) at the ear1ier times, but*they are-merely conservativ~ estimates near the times when t~e water level approaches and*passes the level of the top of the wedge shape. The total impulse of the impact transient is expected to be conservative, since it exceeds, somewhat, the impulse assodated with an impact on a flat beam of the same_wid\h as the wedge.

For deflector designs that do not exactly match those shown in Figures 2.10-3 1* *. through 2.10-5 in Appe,,:tdix A but differ slightly in either the wedge an~le or the ratio.w/d, the imRact and steady drag *correlation should be based on Wagner's force history for a wedge (Ref.. 27) and on the final steady-state drag, following the basic method des.cribed above. The staff has concluded that the force-time histories specified in Section 2.'10 1 of Appendix A, coupled ~ith the proposed method for defining the pool velocity from the QSTF tests, will assure *a conservative estimate of the deflector impact and drag load transients. 3.5.3 Impact and Drag on Other Internal Structures 11 0ther struct~res,li ~~ the present context, are defined as all structures above the initia1 suppression pool water level, exclusive of the vent system. Typically, 50

these structures are cylindrical pipes or structural beams with a flat surface toward the pool. In addition, gratings may be located above the pool. The LOR presents impact load deffnition techniques for (1) cyHndrical pipes, (2)

*elongated structures whose cross-section is not circular (e.g., I-beams), and*

{3) gratings~ The water impact loads on these commonly encountered structural shapes are discussed separately in the following sections.

3. 5. 3_. i Cylindrical *structures The LOR specifies the impact loading on cylinders in the following manner:

(1) the impact velocity at the ~levation in question is obtained from 9STF tests (Ref. ~41 with adjustment for 'longitudinal position* along the torus derived from the EPRI 3-D test results (Ref.* 20); (2) the impulse of impac*t is calculated from . where I is the impact impulse (lbf-sec), Mh is the hydrodynamic mass of the cylinder under fully submerged conditions (lbm), V0 is the impact"velocity {ft/sec), and gc is the gravitational constant {lbm*f.t/lbf-sec 2 ~; (3) the duration of* impact is taken equal to _the time requ,iretl for the pool to. submerge a 50° inclu.ded angle. of the cylinder; (4) the impact load transient* is assumed to be parabolic in time; and (5) the.drag following impact is based on a standard dra~*coefficient. _As a result of its review of the proposed analysis techn;ques, the staff has concluded' that, although the approach is generally reasonable, the specific assumptions made are not consistent**with applicable test. data. The deficiencies that have been identified are the following: (1) .the parabolic pulse shape is not realistic for cylinders, as ~videnced by more recent impact data (~ef. 25); (2) the empirical factor of 0.2 in the impulse equation is based on limited data {Ref.* 36) and does not bound* the data from other cylinder impact tests {Ref~. 25,37); and {3) the 11 s~andard 11 fully submerged drag coefficient is not appropriate for cylinder drag immediately after impact. 51

The staff's acceptance criteria, as defined in Section 2.7.1 of Appendix A, make extensive use of the recently generated data for rigid cylinder impact (Ref. 35). We believe that this data base is the best available for cylinder impact under Mark I LOCA conditions. This judgment i-s based on the detailed nature of the measurements and on the range of test condi~ions used: impact velocities from 7.6 to 24.2 ft/sec and diameters of 8.25 and 17 inches. Test data developed by ~PRI (Ref-. 25) generally exhibit an impact pressure transient like that shown in Figu~e 3.5-2. With the shape of the impact pulse so defined, there are three parameters that characterize the impact pressure transient: (1) maximum pressure, (2) pulse duration, and (3) impulse. In reality, only two of these are independent; the.third is readily calculated from the other two. In reviewing the available data for cylinders, it was concluded that the maximum pr-essure and the impulse are the more reliably known parameters. This leaves the pulse duration as the derived quantity. In developing the staff's *criteria for impact loads on cylinders, we made use of an assessment of the rigid cylinder impact data, wMch found that the maximum pressure, over the ~~ole range of test condition~. correlates well with the dynamic pressure as* pmax -- 7* 0 [ ;p y2 144gc J where Pmax is the maximum pressure averaged over the projec~ed area (psi) 1 pis the density of water (lbm/ft3 ), Vis the impact velocity (ft/sec), and gc is the gravitational constant (lbm-ft/lbf*sec 2 ). To specify the impulse of impact, one can make use of the correlations for the , hydrodynamic mass of impaht., This was, in fact, done in the LOR where the product 0.2 Mh is the hydrodynamic mass of impact (Mh, by itself, is the hydro-dynamic mass associated-with acceleration of a fully submerged cylinder).

The factor of 0.2 was obtajned from QSTF vent header impact data (Ref. 36). The staff has examined additional*data bases for cylinder impact (Refs; 25,37) and finds that the factor, 0.2, is *too low. To yield a realistically conservative 52

Pmax UJ a:

   . II)

II)

  . La.I a:

0.. TIME Figure 3.5-2 Typical cylindrical target impact pre*ssure .transient. 53

impulse value, t~e acceptance criteria specify that the ~ydrodynamic mass be obtained from a correlation derived for the Mark III containment design {Ref. 37), with a margin of 35 percent added to account for data scatter and

. to encomp_ass other cylindrical impact data. Because the phenomena of pool

. swell impact are basically the same in the Mark I, Mark II, and Mark III containment designs, the PSTF (Mark. III)' impact data are also applicable to . the Mark I design. Once the hydrodynamic mass has been specified, the impulse of impact per unit area is readily determined by _H _V_ 1 M ( ] P A 144 gc where Ip is the impulse per unit area (psi-sec), MH /A is the hydrodynamic mass of impact per unit area *(lbm/ft~},' and V is the i_!llpact velocity {ft/sec). The impulse, as defined here, -does not include the drag contribution to the total force which is assumed to buJld up linearly from zero at the point of initial water contact *to the steady"state value at the end of impact. Sche"!atically,' the value of impulse of impact {excluding drag} is. equal to the area indicated in Fjgure 3.5-2. To specify the pressure. history fully, it is necessary to determine the duration of impact from the values of maximum pressure and impulse. Although it is. possible to fit the shapes of the pulses by exponential curves and to calculate the corresponding pu~se durations, a much s.impler approach was used for the staff 1 s acceptance*criteria. The actual pulse was approximated by a tri.angular pulse of equal peak pressure and impulse. (This approximation will introduce a slight conservatism into the specification.) Figure 3.5~3 shows this step schematically. For a triangular shape the pulse duration is simp~y~ 54

. LLI APPROXIMATE FORCE HISTORY cc:

en V') LLI . cc: CL. T TIME Figure 3.5-3 Cylindrical target impact transient approximation . 55

For the drag which follows the impact, it is not appropriate to use the standard drag coefficients as suggest'ed in the LOR. After impact, an air cavity forms behind the cylinder, causing a departure from standard drag, which .is based on fully submerged flow. The available data base for drag under these 11 open wake 11 conditions is relatively sketchy. This problem is similar to flow with acavi-* tating wake~ and Hoerner (Ref. 28) presents some drag measurements on circula~. cylinders under these conditions. His Figure 15a presents -the drag coefficients as a function of the cavitation number and Reynolds number. Although the data are not quantitatively applicable for the present purposes (the effective cavita-tion number is not known), the curves provide some information on-trends. They show that, if the fl ow is 1ami nar, vent i1 at ion of *the wake can be expected to produce a reduction in the drag coefficient. If the flow is turbulent, however, ventilation of the wake can cause a substantial increase in the drag coefficient. In the case of fully c*avitating flow (base pressure= ambient pressure), both laminar and turbulent c~ses indicate a drag coefficient o~ 0.5, independent of the Reynolds number. In light of the above observations, the appropriate .course of action is to. rely on dra~ data obtain~d und~r conditions approximating~the actual Mark I pool swell phenomena. !he data base that be'st satisfies this requirement is the rigid cylind~r impact data (Ref. 25). The staff estqblished the drag coefficients based on the pressure histories presented for each test run. The pressures at which the pulses seemed to 11 level off 11 were taken to be the drag pressures following impact (shown schematically as PD in Figure 3.5-2). The,calculated drag* coefficients corresponding to these are plotted. in Figure . 3.5:-4 as a fi.unc:tion of Froude number. Froude number was .selected as the correlating parameter because the nature of the open wake behind the body depends primarily on inertia and gravity. (Only data with the larger, 17-inch cylinder are pre-

o I '

sented in Figure 3.5-4, since the smaller, 8.25-inch cylinder lacked sufficient instrumentation around the cylinder to provide accurate force measurements at later times.) The acceptance criteria for drag following impact contain separate specifications for laminar and for turbulent flow. *When the flow is laminar, a standard drag coefficient is used. With a ventilated wake, some reduction in c0 may be realized; however, since the rigid cylinder impact measurements were not in the laminar 56

                                                       . ~* .~              -* ~

e EPRI R;gfd Cylinder Data ...,u,

o. L...L-L.LJ..LJU,.L.LJ.J.J.J..UJlililillllUlW.WllijlUJJ.!J.U!J,

1. 10. , 100.

2 FROUDE NUMBER [ v / Dg) f figure 3. S-4 *cyl:jndrical target drag coefficient fol lowing impact.

regime, it is not possible to quantify this reduction. Thus, a value of 1.2 will be used whl!n Reyno 1ds' number is 1ess than 6 x 105

When the fl ow is turbu-.

lent, a curve'drawn through the measurements, as shown in Figure 3.5-4, has b~en specified for the drag coefficient. At Froude numbers greater than 85, a constant value has been specified, corresponding to the limiting case of a fully cavitating wake .. It should also be noted that the velocity in. the drag*computation is the maximum pool velocity rather than the velocity at the particular elevation of the struc-ture in question. This specification*is consistent with the L~R specification that the maximum pool velocity be used for viscous drag to compensate for neglecting the acceleration component in the total drag calculations. The staff has concluded that the specifications outlined above and presented in Section 2. 7.1 of Appendix Awil 1 provide conservative estimates of the* impact and drag loads on circular*structures. 1*

3. 5. 3. 2 Elongated Nanci rcular Structures The LDR treat.s all noncircular e.longated structures al,ike. A circumscribing

circle is drawn around tht cross-section, and *the structure is then treated as if it were circular.

This method is clearly an approximation. The staff has concluded that the method is *unacceptable because it*is not necessarily a conservative approximatfon,

 .and it can lead. to uny;oeaHstic results. A case in point is a structure .i.in the form. of a flat horizontal strip. The staff estimated that the LOR method for th.is case could underp-~edict the impulse by a factor of 3 and overpredict the*.

pulse duration by a factor of 6.

Because of the difficulty in formulating criteria which are applicable -to all noncircular shapes,* the staff 1 s acceptance criteria include a*specification for flat structures on*ly. As this configuration results in the most severe impact loadfog, all other noncircular structures (e.g., wedges) may be tre.ated 58

as flat structures with the same proj~cted*width, or they must be evaluated on. an ind.ividual basis. The impact specification for flat structures *is. more complex than for cylinders.- First, .there is the potential for trapping air between the target and the pool. Secon~ly,. although some experimental data are available, the detailed force * . histories over a wide *range of velocities are not readily available for flat targets (as they were for*cylinders). Consequently, the type of c~rrelation for maxi.mum pressure that was used for cylinders does not exist for flat targets.

       *For this reason, the impulse and pulse duration have been.used as the principal. i parameters to* define the force history for flat structures. Maximum press~re .*~

1

then becomes the 'deriv~d parameter!.:

The pulse shape i.s taken to be triangular.(as *shown in Figure 3.5-5}. This shape is predicted from theoretical considerations (Refs. *27 ,29). The pressure

imeulse for flat targets is available from the correlations derived for the Mark III containment design (Ref. 37). A 35-percent margfo was found to be necessary to account for scatter evident. fo those data.

The pulse durations for flat targets were deri.ved from the studies of Chuang for the *u.s. Navy (Ref. 35).. His experimental investigation indicates that ff the flat target is perfectly horizontai, a cushion of air is -trapped between the target and pool, and the pu.lse duration is spread out in time. ~h_uang presents an approximaie analytical method for calculating the pulse duration in the presence of this air cushion. In addition,* he tested soine wedges with small deadrise angles (1°, 3°, 6°~ 10°, and 15°) and noted that even a slight inci.ination in f'the target surface, .with respect t~ the pool, was suffident for the air to be

     *pushed out of the way. Specit;cally, he noted that at 1° some air was still present, but.

at 3° the air had' been pushed aside. Since the shortest puls~.

      .durations lead to the largest stresses, the staff has concluded that it would be prudent to .identify the shortest reasonable pulse duration for the .

load speci* fication .. To do this, the pulse duration~ were- determined for two different situations: perfectly horizontal targets with' air cushions and targets i-nclined 59

Pmax t:.... AREA = l"p

VI Cl) I.I.I a:: Q. i

                 .*/
               /                                        PD
             /

1/ T TIME

Figure 3.5-5 Typical .. flat target impact pressure transient. 60

at 1° without air_cushions. Si.nee the a1r cushion disappears at an inclina-tion *somewhere between l O and 3°. the more conservative approach is to ass~me the lower inclination. Further, *based on the range of*Mark I configurations and the typical ~ool surface* profile os*erved in experimental pool swell studies, we conclude that a 1° inclination of the target structure is reasonable.* The pulse durations with the air cushion were calculaied by the analytical

method suggested by Chuang (Ref. 35). For the 1°* incl foation, the pulse durations were determined in the following manner: From examination of the pressure traces for the i ndi_vi dua 1 transduc~rs on wedge surfaces (Figure 8 of Chuang 1 s report) it is apparent that during impact .a high-pressure wave traverses the wedge from the keel to the edge. From these same pressure traces, one can calculate the (approximately constant) speed at .which thh wave travels, or, conver~el~. the time required to traverse a target of a certain width. This traverse time is essenti~lly the pulse duration_ of impact. It was o~served that, for small wedge angles-, the traverse time was directly proportiona-1* to the wedge angle. Thus, one';*could readily establish the pulse dur~tions for a 1° incHnation _at the particular velocity of impact (5.7 ft/sec) tested by Chuang.

To generalize the pulse duration for higher velocities. it is noted from the , theoretkal ,treatment of this problem (Ref. 38) that the pulse travel times* are inve~se]y proportional to the pool velocity. Thus, we obtained the relation t = 0.011 W/V where the factor of 0.011 was established from Chuang*s experiments, Wis the width of the structure, and V ;s the impact velocity (with consistent units). When, using the above equation, the pulse durations were compared .to corresponding pulse durations for a.horizontal target wi~h an air cushion, it was foi,md that, for pool .velocities greater than 7 ft/sec,.* th_e pulse durations for the 1° inclined target were shorter. Therefore, the equation showri above was specifiedror impact velocities greater than 7 ft/sec. At *impact velocities less than 7 ft/sec, I . . the analysis for the air cushion .leads to pulse durations approximated by the equation t =:: 0. 0016 W 61

where t is in seconds** and wis in feet .. With the impulse data from the Hark III impact tests, the triangular shape for the pulse, and the. pulse durations as specified. in the precedfog paragraph, the impact specification is complete. The remaining item, maximum. amplitude of ~he pulse Pmax t~en autoniaticall.Y follows. t Ip =J p(t) 0 dt =31 Pmax *t or Pmax = 21 p/t The drag force on flat targets following impact is based on a drag coefficient equal to 2.0. This vaJue corresponds to the standard drag coefficient for a flat strip, and it' bounds the Mark III drag data for flat geometries. As in* the case of cy1inders, an air wake will exist behind the flat structures immediately after impact. This will probably resul~_in-some reduction in the drag coefficie~t; however, in the absence of reliab'le data, a c of 2.0 has 0 been sp~cified as a conservative limit. The staff has concluded that the specifications which are outlined above and* pres_ented in Section 2. 7. 2 of Appendb A wi 11 provide a conservative estimate o~ the impact and drag loads on flat-surfaced structures. Other noncircular structures may b~ conservatively assessed as equival~nt flat-surfaced structures by selecting the appropriate projected cross-sectional area. In those*cases where the equivalent flat-surface impact is overly conservative, the impact and drag loads will . . have to be defined from applicable test data, using.the methods outlined above. As previously discussed, this spe~ificati~n may result in impact and drag loads that are too conservative for certain structures. Such structures will have to be evaluated- on a case-by-case basis.

3. 5. 3. 3 Grat.ings The LDR does not identify an impact load for gratings. This position is proposed on ~he grounds that none were detected during Mark III tests on a prototypical 62

grating target (Ref. 37).* Thus. the only load identified for gratings during

 ' pool swell is a steady-state drag load.

The staff considers the proposed specification -incomplete. However, the staff

     ,does ~oncur that .for gratings which are *similar_ (in terms of percentage of solid area, bar thickness-to-length ratio, etc.) to that tested for the Mark III_plants, the loads induced by impact are small. Nevertheless, for gratings o! differen~

design. impact loadings may be significant. In addition, even if only a constant. drag is applied, a sudden appli~ation of this load will intr~duce a *dynamic component whicti doubles the corresponding steady-state stresses. To account for both the dynamic nature of the i ni't i a1 loading and fo'r impact loads which may be significant for gratings different from.those tested for Mark In. the staff will require that the drag load be increased by a multiplier given by for Wf < 2000 in/sec where FSE is the load to *be applied to the grating (i.e., the static equivalent load), Wis the width of the bars in the grating (inches), .f is the natural frequency of the lowest mode (Hz).: and D is the static dra~ load. -ln the struc-

  . tural assessment, it must be verified that the higher modes of response do not
    .significantly contribute to the load~ The detailed derivation of this multiplier *
      ;s presented. in Appendix C.4 of*the staff's report on the Mark II Lead Plant
    *Program' {Ref. 39).

This multiplier is to be applied to the steady-state force on the* grating derived from the correlation shown in Section 2.7.3 of Appendix A.

The "st~ff -has conclu.ded that th'is specification* will provide a conservative estmate of the forces on gratings during pool swell. I 3.5.3.4 Fluid-Structure Int.eracti_on During Impact In performing the structural dynamic analysis, one is faced with the question

  . of fluid-structure interaction during imp~ct. The pressure pulses, defined by 63"
                                                .\.
                                               .. \,

., j the load acceptance criteria,. correspond to impact on rigid structures. This is due to the fact that the experimental data.which were used as the basis for characterizing pulse durations (Refs. 25,35,37) were obtained with very rigid models. The real structures above the Mark I pools may be more flexible, with the result that the pressure puls~. during impact, will be modified by the motion of the target. . The motion of a slender uniformly loaded beam is given by the following_ equation (Ref. 40) d' . m Y + E I = ~ = p(t) where m = mass of beam per unit length y '? deflection from unloaded positfon p = force per unit length of beam (p has been ~sed for press~re elsewhere in this report) Consider the total force pa~ composed of the rigid body impact force, Pr and a perturbation, p , due to the fact that the body is deformable. Thus 1 p = Pr + P*1 If one neglects the . damping and

                                   . compressibility of water, the interaction force is simply equal to pi = *mJ where mH = hydrodynam1c mass of impact The minus sign comes from the fact that as the interface moves in the positive direction (away from the water), the total force is reduced.

64

Combining the last three equations~ the retult is

    *my+ E I ~       =p.r *ct) ..- m..v tf" dx 4 or 4

(m + mH).y + El d~ 4Y = Pr (t) It is seen that th~ moti~n (and stresses) ~fa flexibli beam can be talculated by driving it with a rigid beam forcing function. The mass of the beam, ho~ever, must be increased by the hydrodynamic mass *Of impact. Consequently, the staff's criteria (Appendix A, Section 2.7.4) require that the mass *of the impacted. structure be increased by the_ hydrodynamic mass of impact,. a~ derived from the Mark III impact tests (Ref. 37) in the structural analysis. This adjust~ent is not necessary for gratings, because its effect is negligible for these structures. 3.5,3.4 Purely Impulsive Impact When the *1oading .is purel_y impulsive; the ~hape of the pressure history is unimportant; what matters is the area under the curve, i.e., the impulse.* Thus, under these conditions, if the stress calculations have already been performed using the method proposed in the LDR, the calculated stresses may be used with some adjustments

     . r to provide acceptable loads with a minimum of additional effort .

The Mark I Owners Group h_as indicated it would like to use this approa.ch for structures*with natural frequencies less than 30 Hz. to permit the use of existing analyses. The parameter that. determines whether the load is purely impulsive is the ratio of pulse durat;on to the natural per;od of the structure. Theoreti-cally, the loading is purely impulsive only when this ratio i-s zero. For practical purposes, however, the loading may be'.considered approximately impulsive when the ratio is less than 0.2. For a structure with a natural frequ~ncy of less than *30 Hz, this stipulates that the pulse duration, tis t < 0.2/f = 0.0066 sec 65

Using the proposed LOR method for pulse duration. t = 0.0468 0/V = 0.0066 sec gives D/V ~ 0.141 sec as the.condition when the loading can be considered impulsive.* This criterion is shown in Figure 2.7-5 of Appendix A. Although the pulse duration may be short enough for the load to be impulsive, that in itself is not sufficient. The equation proposed in the LOR for calcu~ lating the impulse contained an empirical constant of 0.2, which is too small. This must be increased by 35 precent to encompass a broader data base for cylinder impact (Refs. 25,37).

Since, under impulsive loading, the stresses are propor-

. tional to impulse, the calculated stresses may-simply be-increas~d by a factor of 1. 35. The other correction (as indicated in Appendi~ A, Section 2.7.4) comes from the fact that. drag,. which follows impact, wi.11 contribute

                 .                                        . . to. the stresses under dynamic conditions. The amount of this. co~rection can be obtained from ~he
*dynamic load factor (DLF) curves shown in Figure 2.7-6 of Appendix A. These corrections depend on the ratio ~f pulse duratio~ to the natural period and the ratio of drag pressure to the peak impact pressure for a parabolic pulse.

The DLF curves in Figure 2.7-6 of Appendix A were generated by calculating the 1 response of a single-degree-of-freedom* sy stem to a parabolic force history with-out drag an*d, then, with drag forces of various magnitudes. The staff has concluded that the adjustments to the proposed LOR impact and drag load specification for structures with a natural freque.ncy less than 30 Hz will provide.a reasonably conservative*estimate. of the purely impulsi-ve impact loads. 66

3.6 Pool Swell Froth Impingement Loads

Froth is.an air-water mixture which rises above the pool surface* and may impinge on the torus walls and structures within th~ torus airspace. Subsequently, when the *troth falls back, it creates froth fallback loads. There are two mechanisms by which.froth may be generated:

(1) As the rising pool - strikes the bottom. of the .vent header and/or the vent header deflector, a fro~h spray is formed, which travels upward and to both sides of the vent header. For load definition purposes. this froth is assumed to be* bounded by Region I, as shown in Figure 3.6-1.-' (2) A portion of the water above the expanding air bubble becomes detached from the bulk pool; this water is influenced by only its own inertia and gravi'ty. The "bubble breakthrough 11 creates a _fro~h which rises into the_ airspace beyond the *maximum bulk pool swell height .. This froth is assumed to-be*bounded by Region II, as shown in Figure 3.6-2. The load specification proposed in Section 4.3.5 of the LDR is based on the transfer of all -of the momentum of the froth to the impinged structure. The froth impingement pressure is then given as i,

      *.* Pf = (pf    v2 )/144gc where p = froth impingement pressure (psi) p  =: frot.h density (ibm/ft 3 )

v*= froth impingement velocity (ft/sec) gc = gravitational constant (lbm-ft/1bf-sec2) The froth .density and velocity are established from high-speed* mov.ies of the QSTF tests for Region I. Region II, and froth fallback. While the staff agrees with this approach in general, c~rtafo specific assumptions ar~ not acceptable. These are described below. 67

FROTH REGION I NQte: Region is symmetric.~n both sides of vent header. Figure 3.6-1 Froth impingement.zone - region l. 68

                                        .-'-1 '*
                                                            ~ ....

MAXIMUM POOL

SWELL PROFILE I*.

Figure*3.6-2 Froth impingement zon, - region II. .' 69

For Region I, the proposed load specification assumes that the froth density is 10-percent water density ~nd the froth velocity is equal to the pool surface velocity-just prior to vent header impact. The load duration is 0.08Q seconds, appHed in a direction defined. by the 45° tangent at the bottom of the vent header with no allowance for gravity deceleration. Based on a review of selected QSTF movie frames and analytical results, the staff has concluded that the proposed specification does not adequately describe the loading condition. The froth in Region I is a water spray formed by the displacement and acceleration of the pool surface by the ve~t header. Estimates of the initial' departure velocity of the froth spray were made from the results of analyses performed by the L~s Alamos ,_Scientific ~ab~ratory using the SOLA-SURF computer code (Ref. 41). These calculations provided fluid velocities within the wave formed during impact, as shown in Fi~ure 3.6-3, but .did not extend into the froth regime itself. The analyses indicated that the peak water velocity was more than twice the header impact velocity just. prior to the formation of the. froth. This estimate of the froth source velocity was confirmed by examination of the movie frames. The staff has concluded that. a froth impingement velocity equal to 2.5 times the header impact velocity, corrected for gravitational deceleration to the. point of impingement, is reasonably representative for the range of Mark I configurations. Further, the variation in header impact velocity and gravita-tion.al deceleration will tend to change the direction of the applied load. Consequently, the acceptance criteria also require {Appendix A, Section 2.8) that the load b~ applied in a direction most critical to the-structure within the 90° sector which wfl 1 bound the observed froth vectors. To determine a conservative estimate of the froth density, conservation of momentum and energy were evaluated. Treating the froth as a fluid with uniform initial velodty, Vft _directed at an angle, e, with the horizontal, and having* a mass of froth, mf*,* on eit_her side of the vent header, the vertical momentum equation may .be written (mh + mhf + 2mf) Vi= IP+ 2 mf Vf sine where 70

VENT HEADER

                               '           /        POOL
          ........................... ,;,,, .............   .. ,... ,..... .,  *******,:********11u,,,,,111u1,*,,,111111111111111111111u

_ * * *

l l l l l l l ! ' l l l f l f l l llllt 111111111111111I1111111111111111

                                                                                                                                       ~*
                    ~                                                           .. ...................                     ,.,................................ ..
         , . , 111 uu111 u 111u1no,,11,, u111111111111 uui 11111111
         ..........................................................            ....................................... i ................ ..
                                                                                                                                                        ~
          ,., .. 11ui1'111111u11111u11111111111ttuu1,, .. ,11,1111,1            ~    ...........,...............................,........... .

IIIIHIIIIIIIIUIHIIUIIHlllll*11111111111illHIIIIH IU 111u111,u1,1111111111,,1111111111,111uuun,,u11n111 Ill I U HI II IIIIIHllflllll Uflf U 11111II111111111 IIIUl 111 111111 . . I II ltll'I lllltlU tHtlfl 11111 II II IIIU 111111 fl I* I II

1. 2.

.. ~*.,

        ~ ***~********'"'""""          .....................    '*'"   ** ********* ******* ,,,,.,,., "' "'" u .... ,, .... ., 111                       t.'"
        ,uu*u*'****""'"I 111uu111uu,u111111r1 *,
        ................. ,.,,.,,,.,,,., u ........................ ,
        "" ,11e*1uu11f1u1111U1tUII u UI u111 H 1111111111111 II
                                                                               *...........,,.""~'""'""''"",,,,.,,,II
                                                                               .. , ** , .. , .. ,.,,,.,,.,.,,.,,.,,,,,,1111,~11,u1*11iiu11111
                                                                                                                                                 ...............,1.

ti 1111, i

        ............................ ., ....................... , ** i ..

u******u11111111111tUt1ru1,u1n1u11111a.1u*11111111 ...........................................................

                                                                               *** 11111e11 IIIIIIIIUHI,. Ulll.,lltUll 11111 I II 111 IIU tll
        ..................... 1.. , ... ,, ........................ , ***

I 11,1111111 UUI I II IIHIIIUIU 11 IU 11 hlU 1110111 Ull 111 .......................................................... 11tu11tu~nu111111,~tu111*11,,11uuu11u111u1111111 11t1u*111111*1*1***f11*flllfllll 11111 U I tllll 1111 u111 I 11 lllllflllllllUHIIIIUU.UII II I lflUIIIIIHHIUUIIIII IU I II Ill 111 II HI 11111~1 lflt I ltlll It I fl 1111 f I~ ti I.~ 1 U I fl If I I I

       , 11111u11i11u11u II nn 11111 u11 ~111 ttu, 111111 uu 11111 11111u.111UHHIIUttl1n11111111111:11,111u1u ... , . . . . . .

I 11,etCUrlUlflllltlUIU~ lllllllll llllltlllllllll Utt Ill 11111Ull111U1l1HIIUl11IIUI 1111111111 I 1111111111111 u 1

3. 4.

Figure ~.6-3

Vent-Header impact wave. formation.

71}}

ML19224C325

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