ML22326A244

FOIA-2023-000005 - Resp 1 - Final, Agency Records Subject to the Request Are Enclosed

ML22326A244
Person / Time
Issue date:	11/21/2022
From:	NRC/OCIO
To:
Shared Package
ML22326A242	List: ML22326A243 ML22326A244
References
FOIA-2023-000005
Download: ML22326A244 (1)

Text

10-13-2022 09:44:52 U.S. Nuclear Regulatory Commission Operations Center Report Event #: 53754 Event Type: Power Reactor Site: SEQUOYAH Notify Date/Time: 2018-11 -26 08:31 (EST)

Unit: 2 I Region: 2 I State: TN Event Date/Time: 2018-11 -26 08:16 (EST)

Facility: [1] W-4-LP,[2] W LP Modify Date/Time: 2018-11 -29 00:00 Containment Type: ICE COND ICE COND Notified by: STEPHEN FRIESE Notifications: STEVE ROSE R2DO HOO: BETHANY CECERE CATHY HANEY R2 RA Emergency Class: Unusual Event HO NIEH NRR 10 CFR Sections: BILL GOTT IRD MOC 50.72(a) (1 ) (i) Emergency Declared 50.72(b)(2)(xi) Offsite Notification Unit Scram Code Rx Crit lnit Power lnit RX Mode Curr Power Current RX Mode 2 N No 0 Cold Shutdown 0 Cold Shutdown UNUSUAL EVENT DECLARED FOR EXCESSIVE SMOKE IN CONTAINMENT At 0816 EST, a Notification of Unusual Event was declared for Unit 2 under Emergency Action Level H.U.4 for excessive smoke in the lower level of containment with a heat signal. Onsite fire brigade is responding to the event. A command post is established. Offsite support is requested by the fire brigade. No flames have been observed as of this report.

The NRC Resident Inspector and State and Local government agencies will be notified.

Notified OHS SWO, FEMA Operations Center, OHS NICC, FEMA NWC (email), OHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • UPDATE ON 11 /26/18 AT 1036 EST FROM BILL HARRIS TO JEFFREY WHITED***

At 1036 EST, Sequoyah Nuclear Station Unit 2 terminated the Notice of Unusual Event. The licensee determined that the source of the smoke in containment was oil on the pressurizer beneath the insulation, that heated up during plant heatup. The licensee did not see visible flame during the event. The licensee is still working to determine if there was any damage to the pressurizer.

The licensee will notify the NRC Resident Inspector.

Notified R2DO (Rose), R2RA (Haney), NRR (Nieh), IRD MOC (Gott), OHS SWO, FEMA Operations Center, OHS NICC, FEMA NWC (email), OHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• * *UPDATE ON 11 /26/18 AT 1337 EST FROM STEPHEN FRIESE TO KARL DIEDERICH***

Following declaration of the Notification of Unusual Event, TVA media relations communicated with the local media regarding the event.

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Rose).

• • • UPDATE ON 11 /26/18 AT 1551 EST FROM STEPHEN FRIESE TO DONG PARK***

"At 1036 EDT, Sequoyah Nuclear Plant (SON) terminated the Notification Of Unusual Event (NOUE) due to initial report of heat and smoke in Unit 2 Lower Containment.

"At 1000 EDT, it was determined that no fire had occurred. Due to difficulty of access to some of the areas being searched, the source could not be identified prior to 1000 EDT. No visible flame (heat or light) was observed.

10-13-2022 09 :44:52 U.S. Nuclear Regulatory Commission Operations Center Report Page 1 of 5 Page 1 of 29

10-13-2022 09:44:52 U.S. Nuclear Regulatory Commission Operations Center Report 2 "The source of the smoke was determined to be residual oil from a hydraulic tool oil in contact with pressurizer piping.

The pressurizer piping was being heated up to support Unit 2 start-up following U2R22 refueling outage. Once the residual oil dissipated, the smoke stopped. It has been concluded that no fire or emergency condition existed.

"Unit 2 is currently in Mode 5, maintaining reactor coolant temperature 160F-170F and pressure 325psig-350psig with 2A Residual Heat Removal (RHR) system in service in accordance with U2R22 refueling outage plan."

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Rose).

• * *RETRACTION ON 11/29/2018 AT 1358 EST FROM FRANCIS DECAMBRA TO ANDREW WAUGH* * *

"Sequoyah Nuclear Plant (SON) is retracting this notification based on the following additional information not available at the time of the notification:

"Following a full Reactor Building inspection, it was concluded that a fire did not exist. The source of the smoke originally reported was later determined to be residual oil from a hydraulic tool in contact with pressurizer piping. Once the residual oil dissipated, the smoke stopped. The source of heat originally reported was normal heated conditions associated with the pressurizer commensurate with plant conditions. SON reported initially based on the available information at the time and to ensure timeliness with emergency declaration and reporting notification requirements."

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Shaeffer) .

10-13-2022 09 :44:52 U.S. Nuclear Regulatory Commission Operations Center Report Page 2 of 5 Page 2 of 29

10-13-2022 09:44:52 U.S. Nuclear Regulatory Commission Operations Center Report 3 Event#: 54531 Event Type: Power Reactor Site: WATTS BAR Notify Date/Time: 2020-02-19 10:20 (EST)

Unit: 1 2 I Region: 2 / State: TN Event Date/Time: 2020-02-19 09:57 (EST)

Facility: [1] W-4-LP,[2] W-4-LP Modify Date/Time: 2020-02-20 00:00 Containment Type: ICE COND ICE COND Notified by: JUSTIN GALLAGHER Notifications: RANDY MUSSER R2DO HOO: DONALD NORWOOD LAURA DUDES R2RA Emergency Class: Unusual Event HO NIEH NRR 10 CFR Sections: CHRIS MILLER NRR EO 50.72(a) (1 ) (i) Emergency Declared SILAS KENNEDY IRD TOM STEPHEN BC Unit Scram Code Rx Crit lnit Power lnit RX Mode Curr Power Current RX Mode 1 N No 0 Hot Standby 0 Hot Standby 2 N Yes 100 Power Operation 100 Power Operation NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN CONTROL BUI LDING "At 0957 EST on February 19, 2020, a Notification of Unusual Event [NOUE] has been determined to be present at the Watts Bar plant Unit 1 under criteria HU4 for a fire potentially degrading the safety of the plant (fire for more than 15 minutes).

"The NRC Senior Resident Inspector has been notified for this event."

Notified OHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), OHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • UPDATE ON 02/19/2020 AT 1151 EST FROM ANDREW WALDMANN TO DONALD NORWOOD***

The fire was declared extinguished at 1033 EST. The NOUE was terminated at 1126 EST. The investigation into the cause of the fire is in progress.

Notified R2DO (Musser), NRR EO (Miller), and IRD MOC (Kennedy). Additionally, notified OHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), OHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • RETRACTION ON 2/20/2020 AT 1453 EST FROM MICHAEL BUTHEY TO RICHARD L. SMITH* **

"Watts Bar Nuclear Plant (WBN) is retracting Event Notice 54531 (NOUE notification) based on the following additional information.

"WBN reported a condition that was determined to meet the definition of a FIRE in the plant Emergency Preparedness Implementing Procedures (EPIP) based on indications available to the decision-maker at the time the declaration was made. A fire, without observation of flame, is considered present if large quantities of smoke and heat are observed.

"Moderate quantities of smoke were observed coming from an electrical cabinet not required to support safe plant operation. Once Fire Brigade personnel were able to access the affected room, no evidence of flame or significant heat was observed. Plant personnel ultimately determined that an overheated electrical component (transformer) resulted in the smoke. As such , the actual conditions did not meet the EPIP definition of a fire."

The NRC Resident Inspector has been notified of this retraction.

Notified R2DO (Musser), NRR EO (Miller), and IRD MOC (Kennedy).

10-13-2022 09 :44:52 U.S. Nuclear Regulatory Commission Operations Center Report Page 3 of 5 Page 3 of 29

10-13-2022 09:44:52 U.S. Nuclear Regulatory Commission Operations Center Report 4 Event #: 55866 Event Type: Power Reactor Site: Sequoyah Notify Date/Time: 2022-04-29 00: 19 (EDT)

Unit: 1 2 I Region: 2 / State: TN Event Date/Time: 2022-04-28 23:55 (EDT)

Facility: [1] W-4-LP,[2] W-4-LP Modify Date/Time: 2022-05-02 21 :51 Containment Type:

Notified by: Brian Klein Notifications: Miller, Mark R2DO HOO: Ossy Font Andrea Veil NRR Emergency Class: Unusual Event Laura Dudes R2RA 10 CFR Sections: Gott, William IR 50.72(a) (1 ) (i) Emergency Declared Unit Scram Code Rx Crit lnit Power lnit RX Mode Curr Power Current RX Mode 1 N Yes 100 Power Operation 100 Power Operation 2 N Yes 100 Power Operation 100 Power Operation NOTICE OF UNUSUAL EVENT The following is a summary of information provided by the licensee via telephone:

On 04/28/22, at 2355 EDT, with both Sequoyah Unit 1 and 2 in Mode-1, 100 percent, a Notice of Unusual Event was declared due to receiving two seismic alarms and security feeling ground movement. Additionally, security in a tower heard an explosion. Both units remain in Mode- 1, 100 percent and they are investigating the validity of the seismic alarms before proceeding with the Abnormal Operating Procedure required shutdown.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRG Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Notified OHS SWO, FEMA Operations Center, CISA Central , FEMA NWC (email) , OHS NRCC THO Desk(email), and OHS Nuclear SSA (email).

• • • UPDATE ON 04/29/2022 AT 0410 EDT FROM BRIAN KLEIN TO OSSY FONT***

The following is a summary of information provided by the licensee via telephone:

On 4/29/22, at 0406 EDT, Sequoyah Unit 1 and Unit 2 terminated the Notice of Unusual Event. The Civil Engineers determined that the alarms were due to a failed seismic indicator channel. Through interviews, only one security officer felt g round movement for a couple of seconds and heard a faint rumbling sound.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRG Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Notified R2DO (Miller) , NRR EO (Miller), and IR MOC (Gott) v ia email.

Additionally, notified OHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email) , OHS NRCC THO Desk(email), and OHS Nuclear SSA (email) .

• *

• RETRACTION ON 05/02/2022 AT 21 18 EDT FROM SCOTT SEAL TO LLOYD DESOTELL * *

• The following information was provided by the licensee via email:

10-13-2022 09 :44:52 U.S. Nuclear Regulatory Commission Operations Center Report Page 4 of 5 Page 4 of 29

10-13-2022 09:44:52 U.S. Nuclear Regulatory Commission Operations Center Report 5 "SON [Sequoyah Nuclear Plant] is retracting the previous NOUE [Notice of Unusual Event] declaration made on 4/28/22 at 2355 [EDT] based on Emergency Action Level HU2 for a seismic event greater than Operating Basis Earthquake levels. Following the declaration of the NOUE, the station reviewed all available indications and determined that a seismic event had not occurred. The instrumentation failure was documented under Event Notification #55867."

Notified R2DO (Miller), and IR MOC (Gott), NRA EO (Miller) via email.

10-13-2022 09 :44:52 U.S. Nuclear Regulatory Commission Operations Center Report Page 5 of 5 Page 5 of 29

10-13-2022 10:21 :50 U.S. Nuclear Regulatory Commission Operations Center Report Logbook Entry: 54321 HOO: BETHANY CECERE Emergency Class: NON EMERGENCY Report Type: POW Event Site: SEQUOYAH Log Entry Datetime: 2018-11 -26 08 :31 :00 Event #: 53754 Notify Datetime: 2018-11-26 08:31 Event Datetime: 2018-11-26 08:16 UNUSUAL EVENT DECLARED FOR EXCESSIVE SMOKE IN CONTAINMENT Logbook Entry: 54322 HOO: JEFFREY WHITED Emergency Class: UNUSUAL EVENT Report Type : 50.72 UPDATED Event Site: SEQUOYAH Log Entry Datetime : 2018-11 -26 00:00:00 Event#: 53754 Notify Datetime: 2018-11 -26 00:00 Event Datetime: 2018-11 -26 00:00

• • • EVENT #53754 UPDATED***

Logbook Entry: 54324 HOO: KARL DIEDERICH Emergency Class: UNUSUAL EVENT Report Type : 50.72 UPDATED Event Site: SEQUOYAH Log Entry Datetime: 2018-11 -26 00:00:00 Event#: 53754 Notify Datetime: 2018-11-26 00:00 Event Datetime: 2018-11-26 00:00

• • • EVENT #53754 UPDATED***

Added 50.72(b)(2)(xi), Offsite Notification.

Logbook Entry: 54326 HOO: DONG HWA PARK Emergency Class: UNUSUAL EVENT Report Type : 50.72 UPDATED Event Site: SEQUOYAH Log Entry Datetime : 2018-11-26 00:00:00 Event #: 53754 Notify Datetime: 2018-11-26 00:00 Event Datetime: 2018-11-26 00:00

• • • EVENT #53754 UPDATED ***

Logbook Entry: 54346 I HOO: ANDREW WAUGH Emergency Class: UNUSUAL EVENT 10-13-2022 10:21 :50 U.S. Nuclear Regulatory Commission Operations Center Report Page 1 of 2 Page 6 of 29

10-13-2022 10:21 :50 U.S. Nuclear Regulatory Commission Operations Center Report 2 Report Type: 50.72 REPORT Event Site: SEQUOYAH Log Entry Datetime : 2018-11-29 00:00:00 Event # : 53754 Notify Datetime : 2018-11-26 00:00 Event Datetime: 2018-11 -26 00:00 m EVENT #53754 RETRACTION ***

10-13-2022 10:21 :50 U.S. Nuclear Regulatory Commission Operations Center Report Page 2 of 2 Page 7 of 29

10-13-2022 10:20:31 U.S. Nuclear Regulatory Commission Operations Center Report Logbook Entry: 57351 HOO: DONALD NORWOOD Emergency Class: UNUSUAL EVENT Report Type: POW Event Site : WATTS BAR Log Entry Datetime : 2020-02-19 11 :30:00 Event#: 54531 Notify Datetime: 2020-02-19 10:20 Event Datetime: 2020-02-19 09:57 NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN CONTROL BUILDING Logbook Entry: 57355 HOO: DONALD NORWOOD Emergency Class: UNUSUAL EVENT Report Type : 50.72 UPDATED Event Site: WATTS BAR Log Entry Datetime : 2020-02-19 00:00:00 Event#: 54531 Notify Datetime: 2020-02-19 00:00 Event Datetime: 2020-02-19 00:00

• • • EVENT #54531 UPDATED***

Logbook Entry: 57363 HOO: RICHARD SMITH Emergency Class: UNUSUAL EVENT Report Type : 50.72 RETRACTED Event Site: WATTS BAR Log Entry Datetime : 2020-02-20 00:00:00 Event#: 54531 Notify Datetime: 2020-02-19 00:00 Event Datetime: 2020-02-19 00:00

• • • EVENT #54531 RETRACTED***

10-13-2022 10:20:31 U.S. Nuclear Regulatory Commission Operations Center Report Page 1 of 1 Page 8 of 29

10-13-2022 1 0 :22 :46 U.S. Nuclear Regulatory Commission Operations Center Report Logbook Entry: 62155 HOO: Ossy Font Emergency Class: UNU Report Type: POW Event Site: Sequoyah Log Entry Datetime : 2022-04-29 01 :51 :00 Event #: 55866 Notify Datetime: 2022-04-29 01 :50 Event Datetime: 2022-04-29 01 :50 NOTICE OF UNUSUAL EVENT Logbook Entry: 62171 HOO: Lloyd Desotel! Emergency Class: UNU Report Type : POW Event Site: Sequoyah Log Entry Datetime : 2022-05-02 21 :51 :00 Event #: 55866 Notify Datetime: 2022-05-02 21 :18 Event Datetime: 2022-04-28 23:55 Event has been retracted 10-13-2022 10:22:46 U.S. Nuclear Regulatory Commission Operations Center Report Page 1 of 1 Page 9 of 29

From: Hoc, HOO X Sent: Tue, 3 May 2022 01:34:15 +0000 To: Seal, Scott Bradley; Hoc, HOO X Cc: Urbanski, Robert James; McNeil, Andrew Clair Subject : RE: NOUE retraction for EN 55866 Received.

Headquarters Operations Officer U. S. Nuclear Regulatory Commission

' phone: 301-816-5100 7 fax: 301-816-5151

!S;l hoo.hoc@nrc.gov

!S;l secure: hool@nrc.sgov.gov l ,~ S ,

/n(<<l.l#f twp/, mu/mt F;..r1,....,.,,.,,

From: Seal, Scott Bradley <sbseal@tva.gov>

Sent : Monday, May 2, 2022 9:30 PM To : Hoc, HOO X <H001@nrc.gov>

Cc: Urbanski, Robert James <rjurbanski@tva.gov>; McNeil, Andrew Clair <acmcneil@tva.gov>

Subject:

[External_Sender] NOUE retraction for EN 55866 Email below follows up phone notification made.

SQN is retracting the previous NOUE declarat ion made on 4/28/22 at 2355 based on Emergency Act ion Level HU2 for a seismic event greater than Operating Basis Earthquake levels. Following the declaration of the NOUE, the station reviewed all available indications and determined that a seismic event had not occurred. The instrumentation failure was documented under Event Notification #55867.

Scott Seal Shift Manager 423-843-6211 (w) l(b)(6) l(m) llE NOTICE: This electronic message transmission contains information that may be TVA SENSITIVE, TVA RESTRICTED, or TVA CONFIDENTIAL. Any misuse or unauthorized disclosure can result in both civil and criminal penalties. If you are not the intended recipient, be aware that any disclosure, copying ,

distribution, or use of the content of this information is prohibited. If you have received this communication in error, please notify me immediately by email and delete the original message Page 10 of 29

From: RightFax E-mail Gateway Sent: Thu, 29 Nov 2018 19:09:11 +0000 To: Hoc, HOO X

Subject:

Received from ANI: '1001' Attachments: 00000664.PDF Received from ANI: '1001' Account: l 00l 11/29/2018 2:07:18 PM Transmission Record Received from remote ID:

Inbound user ID HOO I, routing code I 001 Result: (0/352;0/0) Success Page record: I - 2 Elapsed time: Ol: 14 on channel 3 Page 11 of 29

r-lOU-08-200'3 05: 05 SE0UO'lAH r-lUC PL T P.01 NRC FORM 361 U.S. NUCLEAR REGULATORY COMMISSION (12-2C00) OPERATIONS CENTER REACTOR PLANT EVENT NOTIFICATION WORKSHEET EN# 53754 NRC OPERATION TELEPHONE NUMBER: PRIMARY - 301-816-5100 or 800-532-3469*, BACKUPS -- 11 st) 301-951-0550 or 800-449-3694',

[2nd) 301-415-0550 and [3rd] 301-415-0553 'Licensees who maintain their own ETS are "rovlded these telenhone numbers.

NOTIFICATION TIME FACILITY OR ORGANIZATION UNIT NAME OF CALLER CALL BACK#

1358 Sequoyah Nuclear Plant 2 Francis Decambra (423) 843-6401 EVENT TIME & ZONE EVENTOATE POWER/MODE BEFORE POWER/MODE AFTER 1358 ET 11/29/2018 0% I Mode 5 0% I Mode 5 1-,_ _,cEV.:c:E~NTe..,CcLAe,:ScS~l~Fl~C~A~T~IO°"'N~S----l--'1~-H~*"*~N~o~n~-E~m~*~*ca,**e~n~c*t..,.10,c::C~F~R~5~0".7c2ei:<"b"~*1~"'-I O M(AJ __ Sale s10 Capability __ AINA lJ GENCRAL EMERGENCY _G~~l~EC O TS Devialion ALJ~V _[J (v)(B) ~-~~-~~~~'~'~- _________ _ AINB

_Q ~TE ARFA 1-:MERGENCY SITIAAEC ,..;;*c*"s'o*cNaoan'--=**m****.-::****";*z...;*1a0cCaFcR:.:..:5c0c.7c2:,:"bel*'sl-4-)0. _!_V)(C_) Control of Rao Release AINC 0 ALERT ALEIAAEC O (i) TS Required SID ASHU O (v)(D) Accident M*tigation AINO UNUSUAL EVENT __________u_~-~I~~~- _C)_ (1v)(A) ECCS Discharge to ~CS IICCS O (xii) DHsite Medmal AMEO 0 (see nexteol1.1mn$) _Q \iv)(B) RPSActlH1.t1o._:,_(seram) = {,_m ) _ _<_o_,,_c_*o_m_m_<A_s_m_,_,_,, ,~~~~~A_C_O_M~

50.72 NON-EMERGENCY ARPS_s 0 0 0 0 PHYSICAi SECURITY (73 71) DODD O (xi) Offs,te No~fication APRE GO-Day Optional 10 CFR 60.73(a)(1)

~-T~_RIA.~~~~o~uRe __ __ __ _____ ~?~ f,,,~*o*He*e*aNaocn,-,E,m0e0,_.,**e,n,c,__,*1000C,F,_,,R,5000.7 02.,,*b,o, "3,_ '.µ.,J~l_~c"s**c*-c;s,0,0,0me;'c'o'='*c*::c."c'c"'c'c";"~...,cA;IN0v'--l lJ FITNE~~-_F~-~- ~~~------- _________________ _!:1~1:1:_ D {11J(AJ Ue1Jra?~ :~_nd~1on ADE"G Other Unspecified Requirement (Identify) 0 OTHER UNSr'ECIFIEO REQMT. (see last column) 0 (11)(0) l.!_nan~_yze~_~__:'~dili~_n ____ AUNA [Z] 11elraction of CN 53754 NONR t-~:,~,,~o~-~--MA~-~,o~N~O~N~<~*=*===*====N~l~N~,~ ~~,,~,)~{A~):::'.S~p~"~~"tdSystem Actuatiori AESF LJ .. -- ------- --- -- -- --- -- NONR Include: Systems affeeted, actua1ions Md their initiatin<;i signals, causes, effect of event on pla~t. ac1,ons taken or planned, etc (Continue on back)

Retraction to EN 53754 Sequoyah Nuclear Plant (SON) is retracting this notification based on the following additional information not available at the time of the notification:

Following a full Reactor Building inspection, it was concluded that a fire did not exist. The source of the smoke originally reported was later determined to be residual oil from a hydraulic tool in contact with pressurizer piping. Once the residual oil dissipated, the smoke stopped. The source of heat originally reported was normal heated conditions associated with the pressurizer commensurate with plant conditions. SQN reported initially based on the available information at the time and to ensure timeliness with emergency declaration and reporting notification requirements.

1-'NoOcTe1FclsCeAeTI*OaNoS,__ _ _J._VcEeS,w....eNeOw_w,,,,Le<a..e*"-1E ANYTHING UNUSUAL OR NRC RESIDENT ____ __ IZ] ____ 0 ______ 0 ____ NOT UNDERSTOOD?

D YES (Explain above} @NO

~T~!E(s) Q _____@__1----------- DID ALL SYSTEMS

@YES D NO (&plain above)

LOCAL .0 IZI__ D FUNCTION AS REQUIRED?

O 0 I

IZ] ESflMA, ED I0 OTHER GOV AGENCIES MOOE Of OPERATION ADDITIONAL INFO ON BACK UNT1L CORRECTED Mod S RESTART DATE 12/3/2018 YES 0 NO MEDIA/PRESS RELEASE 0 e (MM/DDfYYYYI NRC FORM 361 (12.2()001 PAGE 1 OF 2 Page 12 of 29

r-lOU-08-200'3 05: 06 SE0UO'lAH r-lUC PL T P.02 NRCFORMJ61 (12-2000) REACTOR PLANT EVENT NOTIFICATION WORKSHEET (CONTINUED)

ADDITIONAL INFORMATION

~ L RELEASES: CHECK OR FILL I APPLICABLE JTEM;:, ex ..lan

• ns should in event ,;

0 LIQUID RELEASE 10[ GASEOUS RELEASE UNPlANNED RELEASh_JI PLANNED RELEASE 10 ONGOING ID TERMINATED MONITORED 10 I UNMONITORED OFFSITE RELEASE OJ T S. EXCEEDED lo RM ALARMS ID AREAS EVACUATED

PERSONNEL EXPOSED OR CONTAMINATED OFFSITE PROTECTIVE ACTIONS RECOMMENDED *state release path in descnption Release Rate (Ci/sec)  % T. S. LIMIT HOO GUIDE Total Activity (Ci)  % T. S. LIMIT HOO GUIDE Noble Gas 0.1 Cl/sec 1000Ci Iodine 10 uCi/sec 0.01 Ci Particulate 1 uCl/sec 1 mCI Liquid (excluding tritium and 10 uCl/mln 0.1 Ci dinolved noble aase.sl Liquid (tritium) 0.2Ci/min SCI Total PLANT STACK CONDENSER/AIR EJECTOR MAIN STEAM LINE SG BLOWDOWN OTHER RAD MONITOR READINGS ALARM SETPOINTS

% T. S. LIMJT(ifapplicable}

RCS OR SG TUBE LEAKS: CHECK OR FJLL JN APPLICABLE ITEMS: (specific deta/lslexplanatlons should be covered in event description)

LOCA TIQN OF THE LEAK (e g, SG #. valve. p1pe, etc.)

LEAK RATE UNITS [!pm/gpd T. $. LIMITS SUDDEN OR LONG-TERM DEVELOPMENT LEAK START DATE TIME COOLANT ACTIVITY PRIMARY SECONDARY ANO UNITS:

UST OF SAFETY RELATED EQUIPMENT NOT OPERATIONAL EVENT DESCRIPTION (Continu"d from front)

NRC FORM ~6\ (12 2000) PAGE20F2 TOTAL P.02 Page 13 al 29

From: Seal, Scott Bradley Sent: Tue, 3 May 2022 01:29:42 +0000 To: Hoc, HOO X Cc: Urbanski, Robert James; McNeil, Andrew Clair Subject : [External_Sender] NOUE retraction for EN 55866 Email below follows up phone notification made.

SQN is retracting the previous NOUE declaration made on 4/28/22 at 2355 based on Emergency Action Level HU2 for a seismic event greater than Operating Basis Earthquake levels. Following the declaration of the NOUE, the station reviewed all available indications and determined that a seismic event had not occurred. The instrumentation failure was documented under Event Notification #55867.

Scott Seal Shift Manager 423-843-6211 (w) l(b)(6) l (m)

NOTICE: This electronic message transmission contains information that may be TVA SENSITIVE, TVA RESTRICTED, or TVA CONFIDENTIAL. Any misuse or unauthorized disclosure can result in both civil and criminal penalties. If you are not the intended recipient, be aware that any disclosure, copying, distribution, or use of the content of this information is prohibited. If you have received this communication in error, please notify me immediately by email and delete the original message Page 14 of 29

From: Friese, Stephen Se nt: Mon, 26 Nov 2018 18:42:26 +0000 To: Hoc, HOO X Cc: Harris, Walter W Jr

Subject:

[External_Sender] NRC Form 361 - SQN 11/26/2018 Attachments: NRC Form 361 - SQN 11-26-18 EN.pdf Please find attached form 361 for TVA media relations communicating with the local media regarding the NOUE {EN: 53754).

Will call to confirm receipt of attachment.

Thank you, Stephen Friese Unit 1 SRO Page 15 of 29

NRC FORM 361 U.S. NUCLEAR REGULATORY COMMISSION (12-2000) OPERATIONS CENTER REACTOR PLANT EVENT NOTIFICATION WORKSHEET EN#

NRG OPERATION TELEPHONE NUMBER: PRIMARY -- 301 -816-5100 o r 800-532-3469*, BACKUPS -- [1st] 301 -951 -0550 or 800-449-3694*,

[2nd] 301-4 15-0550 and [3rd] 301 -415-0553 *Licensees who maintain their own ETS are provided these telephone numbers.

NOTIFICATION TIME FACILITY OR ORGANIZATION UNIT NAME OF CALLER CALL BACK#

1337 Sequoyah 2 Stephen Friese (423) 843-6211 EVENT TIME & ZONE EVENT DATE POWER/MODE BEFORE POWER/MODE AFTER 1000 EDT 11/26/2018 0% I Mode 5 0% I Mode 5 EVENT CLASSIFICATIONS 1-Hr. Non-Emergency 10 CFR 50.72(b)(1) (v)(A) Safe SID Capability AINA GENERAL EMERGENCY GENIAAEC TS Deviation ADEV (v)(B) RHR Capability AINB SITE AREA EMERGENCY SIT/AAEC 4-Hr. Non-Emergency 10 CFR 50.72(b)(2) (v)(C) Control of Rad Release AINC ALERT ALE/AAEC (i) TS Required S/D ASHU (v)(D) Accident Mitigation AIND UNUSUAL EVENT UNU/AAEC (iv)(A) ECCS Discharge to RCS ACCS (xii) Offsite Medical AMED 50.72 NON-EMERGENCY (see next columns) (iv)(B) RPS Actuation (scram) ARPS (xiii) Loss Comm/Asmt/Resp ACOM PHYSICAL SECURITY (73 .71) DODD 0 (xi) Offsite Notification APRE 60-Day Optional 10 CFR 50.73(a)(1)

MATERIAUEXPOSURE B??? 8-Hr. Non-Emen:iencv 10 CFR 50.72(b)(3) Invalid Specified System Actuation AINV FITNESS FOR DUTY HFIT (ii)(A) Degraded Condition ADEG Other Unspecified Requirement (Identify)

OTHER UNSPECIFIED REQMT. (see last column)

(ii)(B) Unanalyzed Condition AUNA NONR INFORMATION ONLY NINF (iv)(A) Specified System Actuation AESF NONR DESCRIPTION Include: Systems affected, actuations and their initiating signals, causes, effect of event on plant, actions taken or planned, etc. (Continue on back) 10CFR50.72(b )(2)(xi)

Following declaration of a Notification of Unusual Event at Sequoyah Nuclear Plant (EN: 53754), TVA media relations communicated with the local media regarding the event.

NOTIFICATIONS YES NO WILL BE ANYTHING UNUSUAL OR NOT UNDERSTOOD?

D YES (Explain above) 0 NO NRC RESIDENT 0 STATE(s)

--~ 0 DID ALL SYSTEMS 0 YES D NO (Explain above)

LOCAL _o_ 0 FUNCTION AS REQUIRED?

OTHER GOV AGENCIES

~

0 MODE OF OPERATION UNTIL CORRECTED:

IESTIMATED RESTART DATE: 12/3/2018 I ADDITIONAL INFO ON BACK MEDIA/PRESS RELEASE 0

Mode 5 (MM/DD/YYYY) 0 YES 0 NO NRC FORM 361 (12-2000)

PAGE 1 OF 2 Page 16 of 29

NRC FORM 361 (12-2000) REACTOR PLANT EVENT NOTIFICATION WORKSHEET (CONTINUED)

ADDITIONAL INFORMATION RADIOLOGICAL RELEASES: CHECK OR FILL IN APPLICABLE ITEMS fsnecific d1>tailslexnlanations should be cover1>d in ev1>nt d<>ccrintinn l D LIQUID RELEASE IOI GASEOUS RELEASE D UNPLANNED RELEASE IOI PLANNED RELEASE ID ONGOING ID TERMINATED D MONITORED l I UNMONITORED D OFFSITE RELEASE lI T. S. EXCEEDED lo RM ALARMS ID AREAS EVACUATED D PERSONNEL EXPOSED OR CONTAMINATED D OFFSITE PROTECTIVE ACTIONS RECOMMENDED *state release path in description Release Rate {Ci/sec)  % T. S. LIMIT HOO GUIDE Total Activity (Ci)  % T. S. LIMIT HOO GUIDE Noble Gas 0 .1 Ci/sec 1000 Ci Iodine 10 uCi/sec 0.01 Ci Particulate 1 uCi/sec 1 mCi Liquid (excluding tritium and 10 uCilmin 0.1 Ci dissolved noble aases)

Liquid (tritium) 0.2 Ci/min 5 Ci Total PLANT STACK CONDENSER/AIR EJECTOR MAIN STEAM LINE SG SLOWDOWN OTHER RAD MONITOR READINGS ALARM SETPOINTS

% T. S. LIMIT(if applicable)

RCS OR SG TUBE L EAKS: CHECK OR FILL IN APPLICABLE ITEMS: (specific details/explanations should be covered in event description)

LOCATION OF THE LEAK (e.g., SG #, valve, pipe, etc.)

LEAK RATE UNITS: gpm/gpd T. S. LIM ITS SUDDEN OR LONG-TERM DEVELOPMENT LEAK START DATE TIME COOLANT ACTIVITY PRIMARY SECONDARY AND UNITS:

LIST OF SAFETY RELATED EQUIPMENT NOT OPERATIONAL EVENT DESCRIPTION (Continued from front)

NRC FORM 361 (12-2000) PAGE 2 OF 2 Page 17 of 29

From: Friese, Stephen Sent: Mon, 26 Nov 2018 20:52:29 +0000 To: Hoc, HOO X Cc: Harris, Walter W Jr

Subject:

[External_Sender] Update to NOUE EN: 53754 Attachments: NRC Form 361 - SQN 11-26-2018 update.pdf Please find attached form 361 for TVA update regarding the NOUE EN: 53754.

Will call to confirm receipt of attachment.

Thank you, Stephen Friese Unit 1 SRO Page 18 of 29

NRC FORM 361 U.S. NUCLEAR REGULATORY COMMISSION (12-2000) OPERATIONS CENTER REACTOR PLANT EVENT NOTIFICATION WORKSHEET EN# 53754 NRG OPERATION TELEPHONE NUMBER: PRIMARY -- 301 -816-5100 or 800-532-3469*, BACKUPS -- [1 st] 301-951-0550 or 800-449-3694*,

[2nd] 301-4 15-0550 and [3rd] 301 -415-0553 *Licensees who maintain their own ETS are provided these telephone numbers.

NOTIFICATION TIME FACILITY OR ORGANIZATION UNIT NAME OF CALLER CALL BACK#

1551 Sequoyah Nuclear Plant 2 Stephen Friese (423) 843-6211 EVENT TIME & ZONE EVENT DATE POWER/MODE BEFORE POWER/MODE AFTER 1530 EDT 11/26/2018 0% I Mode 5 0% I Mode 5 EVENT CLASSIFICATIONS 1-Hr. Non-Emergency 10 CFR 50.72(b)(1) (v)(A) Safe SID Capability AINA GENERAL EMERGENCY GENIAAEC TS Deviation ADEV (v)(B) RHR Capability AINB SITE AREA EMERGENCY SIT/AAEC 4-Hr. Non-Emergency 10 CFR 50.72(b)(2) (v)(C) Control of Rad Release AINC ALERT ALE/AAEC (i) TS Required S/D ASHU (v)(D) Accident Mitigation AIND UNUSUAL EVENT UNU/AAEC (iv)(A) ECCS Discharge to RCS ACCS (xii) Offsite Medical AMED 50.72 NON-EMERGENCY (see next columns) (iv)(B) RPS Actuation (scram) ARPS (xiii) Loss Comm/Asmt/Resp ACOM PHYSICAL SECURITY (73 .7 1) DODD (xi) Offsite Notification APRE 60-Day Optional 10 CFR 50.73(a)(1)

MATERIAUEXPOSURE B??? 8-Hr. Non-Emen:iencv 10 CFR 50.72(b)(3) Invalid Specified System Actuation AINV FITNESS FOR DUTY HFIT (ii)(A) Degraded Condition ADEG Other Unspecified Requirement (Identify)

OTHER UNSPECIFIED REQMT. (see last column)

(ii)(B) Unanalyzed Condition AUNA 0 Update to EN 53754 NONR INFORMATION ONLY NINF (iv)(A) Specified System Actuation AESF NONR DESCRIPTION Include: Systems affected, actuations and their initiating signals, causes, effect of event on plant, actions taken or planned, etc. (Continue on back)

Update to EN 53754 At 1036 EDT, Sequoyah Nuclear Plant (SON) terminated the Notification Of Unusual Event (NOUE) due to initial report of heat and smoke in Unit 2 Lower Containment.

At 1000 EDT, it was determined that no fire had occurred. Due to difficulty of access to some of the areas being searched, the source could not be identified prior to 1000 EDT. No visible flame (heat or light) was observed.

The source of the smoke was determined to be residual oil from a hydraulic tool oil in contact with pressurizer piping. The pressurizer piping was being heated up to support Unit 2 start-up following U2R22 refueling outage. Once the residual oil dissipated, the smoke stopped. It has been concluded that no fire or emergency condition existed.

Unit 2 is currently in Mode 5, maintaining reactor coolant temperature 160F-170F and pressure 325psig-350psig with 2A Residual Heat Removal (RHR) system in service in accordance with U2R22 refueling outage plan.

NOTIFICATIONS YES NO WILL BE ANYTHING UNUSUAL OR NOT UNDERSTOOD?

D YES (Explain above) 0 NO NRC RESIDENT 0 STATE(s)

--~ 0 DID ALL SYSTEMS 0 YES D NO (Explain above)

LOCAL _o_ 0 FUNCTION AS REQUIRED?

OTHER GOV AGENCIES

~

0 MODE OF OPERATION IESTIMATED I ADDITIONAL INFO ON BACK UNTIL CORRECTED: Mode 5 RESTART DATE:

12/3/2018 YES NO MEDIA/PRESS RELEASE 0 (MM/DD/YYYY) 0 NRC FORM 361 (12-2000)

PAGE 1 OF 2 Page 19 of 29

NRC FORM 361 (12-2000) REACTOR PLANT EVENT NOTIFICATION WORKSHEET (CONTINUED)

ADDITIONAL INFORMATION RADIOLOGICAL RELEASES: CHECK OR FILL IN APPLICABLE ITEMS fsnecific d1>tailslexnlanations should be cover1>d in ev1>nt d<>ccrintinn l D LIQUID RELEASE IOI GASEOUS RELEASE D UNPLANNED RELEASE IOI PLANNED RELEASE ID ONGOING ID TERMINATED D MONITORED l I UNMONITORED D OFFSITE RELEASE lI T. S. EXCEEDED lo RM ALARMS ID AREAS EVACUATED D PERSONNEL EXPOSED OR CONTAMINATED D OFFSITE PROTECTIVE ACTIONS RECOMMENDED *state release path in description Release Rate {Ci/sec)  % T. S. LIMIT HOO GUIDE Total Activity (Ci)  % T. S. LIMIT HOO GUIDE Noble Gas 0 .1 Ci/sec 1000 Ci Iodine 10 uCi/sec 0.01 Ci Particulate 1 uCi/sec 1 mCi Liquid (excluding tritium and 10 uCilmin 0.1 Ci dissolved noble aases)

Liquid (tritium) 0.2 Ci/min 5 Ci Total PLANT STACK CONDENSER/AIR EJECTOR MAIN STEAM LINE SG SLOWDOWN OTHER RAD MONITOR READINGS ALARM SETPOINTS

% T. S. LIMIT(if applicable)

RCS OR SG TUBE L EAKS: CHECK OR FILL IN APPLICABLE ITEMS: (specific details/explanations should be covered in event description)

LOCATION OF THE LEAK (e.g., SG #, valve, pipe, etc.)

LEAK RATE UNITS: gpm/gpd T. S. LIM ITS SUDDEN OR LONG-TERM DEVELOPMENT LEAK START DATE TIME COOLANT ACTIVITY PRIMARY SECONDARY AND UNITS:

LIST OF SAFETY RELATED EQUIPMENT NOT OPERATIONAL EVENT DESCRIPTION (Continued from front)

NRC FORM 361 (12-2000) PAGE 2 OF 2 Page 20 of 29

From: Waldmann, Andrew Scott Se nt: Wed, 19 Feb 2020 17:29:26 +0000 To: Hoc, HOO X

Subject:

[External_Sender] WBN NOUE Attachments: WBN NOUE 2-19-20.pdf Please see attached for WBN NOUE ENS 54531 Andrew Waldmann Crew 1 Sh ift Manager Watts Bar Nuclear Plant 423.365.8213 (w) aswaldmann@tva.gov Im NOTICE: This electronic message transmission contains information that may be TVA SENSITIVE, TVA RESTRICTED, or TVA CONFIDENTIAL. Any misuse or unauthorized disclosure can result in both civil and criminal penalties. If you are not the intended recipient, be aware that any disclosure, copying, distribution , or use of the content of this information is prohibited. If you have received this communication in error, please notify me immediately by email and delete the original message.

Page 21 of 29

NRC FORM 361 U.S. NUCLEAR REGULATORY COMMISSION (12-2000)

OPERATIONS CENTER REACTOR PLANT EVENT NOTIFICATION WORKSHEET EN # 54531 NRC OPERATION TELEPHONE NUMBER: PRIMARY -- 301-816-5100 or 800-532-3469', BACKUPS - [1st] 301-951-0550 or 800-449-3694",

[2nd] 301-415-0550 and [3rd] 301-415-0553 ' Licensees who maintain their own ETS are provided these telephone numbers.

NOTIFICATION TIME FACILITY OR ORGANIZATION UNIT NAME OF CALLER CALL BACK#

1020 (EST) Watts Bar Nuclear Plant Justin Gallagher (423) 365-8213 EVENT TIME & ZONE EVENT DATE POWER/MODE BEFORE POWER/MODE AFTER 0957 (EST) 02/19/2020 0/3 0/3

...,,~__E_V_E_N_T_C_LA_S_S_IF_IC_A_T_I_O_N_S_ _---ll-=1_-_H_ r._N _ 5_0_.7_2J.._b...,ll(,._1_)""--1 0

_o_n_-_E_m_e_rg._e_n_c.,.:y_1_0_C_FR (v)(A) Sale Si~_Capability AINA 0 GENERAL EMERGENCY GEN/AAEC O TS Deviation ADEV O (v)(B) RHR Capability AIN~

0 SITE AREA EMERGENCY SIT/AAEC 4-Hr. Non-Emergency 10 CFR 50.72(b)J2} 0 (v)(C) Control of Rad Release AINC 0- ALERT -- ALE/AAEC O (i) TS Required SID ASHU O (v)(D) Accident Mitigation AIND

[Z) UNUSUAL EVENT UNU/AAEC O (iv)(A) ECCS Discharge lo RCS ACCS O (xii) Offsite Medical AMED 0 50.72 NON-EMERGENCY (see next columns) 0 (iv)(B) RPS Actuation (scram) ARPS O (xiii) Loss Comm/AsmVResp ACOM O PHYSICAL SECURITY (73.71) DODD O (xi) Offsite Notification APRE 60-Day Optional 10 CFR 50.73(a)(1) 0 MATERIAUEXPOSURE B??? 8-Hr. Non-Emergency 10 CFR 50.72(b)(3) 0 Invalid Specified System Actuation AINV 1

0 FITNESS FOR DUTY HFIT O (ii)(A) Degraded Condition ADEG Other Unspecified Requirement (Identify)

[) OTHER UNSPECIFIED REQMT. (see last column) O (ii)(B) Unanalyzed Condition AUNA O NONR 0 INFORMATION ONLY ~ 0 (iv)(A) Specified System Actuation AESF O NONR DESCRIPTION Include: Systems affected, actuations and their initiating signals, causes, effect of event on plant, actions taken or planned, etc. (Continue on back)

NOTIFICATION OF UNUSUAL EVENT- PLANT FIRE At 0957 EST on February 19, 2020, a Notification of Unusual Event has been determined to be present at the Watts Bar plant Unit 1 under criteria HU4 for a fire potentially degrading the safety of the plant (fire for more than 15 minutes).

The NRC Senior Resident Inspector has been notified for this event.

X.XXXXXXXXXXXXXXXXXXXXXX.XXUPDATE at 1033 EST X.XXXXXXXXXXXXXXX.XXXXXXXXXXXXXXXXX Fire has been verified to have been put out.

NOTIFICATIONS YES NO WILL BE ANYTHING UNUSUAL OR D YES (Explain above) (Z] NO NRC RESIDENT 0 NOT UNDERSTOOD?

STATE(s) 0 - DID ALL SYSTEMS (Z] YES D NO (Explain above)

LOCAL 0. FUNCTION AS REQUIRED?

OTHER GOV AGENCIES 0 MODE OF OPERATION rSTIMATED ADDITIONAL INFO ON BACK MEDIA/PR ESS RELEASE NRC FORM 361 (12-2000) 0 UNTIL CORRECTED: 3 RESTART DATE:

(MMIDDIYYYY) 02/20/2020 I

YES 0 NO PAGE 1 OF 2 Page 22 of 29

NRC FORM 361 (12*2000) REACTOR PLANT EVENT NOTIFICATION WORKSHEET (CONTINUED)

ADDITIONAL INFORMATION RADIOLOGICAL RELEASES: CHECK OR FILL IN APPLICABLE ITEMS 1~n°, Ifie d 0 *"i'~1°xn/a""tion,: hould be COVMAd in ev* nt d 0 ~crintionl LIQUID RELEASE IOI GASEOUS RELEASE DI UNPLANNED RELEASE PLANNED RELEASE ONGOING ID TERMINATED MONITORED lol UNMONITORED OFFSITE RELEASE I T. S. EXCEEDED RM ALARMS ID AREAS EVACUATED PERSONNEL EXPOSED OR CONTAMINATED OFFSITE PROTECTIVE ACTIONS RECOMMENDED ' State release path in description Release Rate (Ci/sec)  % T. S. LIMIT HOO GUIDE Total Activity (Ci)  % T. S. LIMIT HOO GUIDE Noble Gas 0.1 Ci/sec 1000 Ci Iodine 10 uCi/sec 0.01 Ci Particulate 1 uCi/sec 1 mCi Liquid (excluding tritium and 10 uCi/min 0.1 Ci dissolved noble aases)

Liquid (tritium) 0.2 Ci/min 5 Ci Total PLANT STACK CONDENSER/AIR EJECTOR MAIN STEAM LINE SGBLOWDOWN OTHER RAD MONITOR READINGS ALARM SETPOINTS

% T. S. LIMIT(if applicable)

RCS OR SG TUBE LEAKS: CHECK OR FILL IN APPLICABLE ITEMS: (specific details/explanations should be covered in event description)

LOCATION OF THE LEAK (e.g., SG II, valve. pipe, etc.}

LEAK RATE UNITS: gpm/gpd T . S. LIMITS SUDDEN OR LONG-TERM DEVELOPMENT LEAK START DATE TIME COOLANT ACTIVITY PRIMARY SECONDARY AND UNITS:

LIST OF SAFETY RELATED EQUIPMENT NOT OPERATIONAL EVENT DESCRIPTION (Continued from front)

NRC FORM 361 (12-2000) PAGE 20F2 Page 23 of 29

From: Bruchey, Michael William Se nt: Thu, 20 Feb 2020 19:53:41 +0000 To: Hoc, HOO X

Subject:

[External_Sender] WBN NOUE Retraction EN# 54531 Attachments: 2020-02-19 Ul NOUE Retraction.pdf

Regards, Mike Bruchey Crew 5 Shift Manager WBN Operations NOTICE: This electronic message transmission contains information which may be TVA SENSITIVE, TVA RESTRICTED or TVA CONFIDENTIAL. Any misuse or unauthorized disclosure can result in both civil and criminal penalties. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the content of this information is prohibited. If you have received this communication in error, please notify me immediately by email and delete the original message.

Page 24 of 29

NRC FORM 361 U.S. NUCLEAR REGULATORY COMMISSION (12-2000) OPERATIONS CENTER REACTOR PLANT EVENT NOTIFICATION WORKSHEET EN# 54531 NRG OPERATION TELEPHONE NUMBER: PRIMARY -- 301 -816-5100 or 800-532-3469*, BACKUPS -- [1st] 301-951 -0550 or 800-449-3694*,

[2nd] 301-4 15-0550 and [3rd] 301 -415-0553 *Licensees who maintain their own ETS are provided these telephone numbers.

NOTIFICATION TIME FACILITY OR ORGANIZATION UNIT NAME OF CALLER CALL BACK#

1020 (EST) Watts Bar Nuclear Plant 1 Justin Gallagher (423) 365-8213 EVENT TIME & ZONE EVENT DATE POWER/MODE BEFORE POWER/MODE AFTER 0957 (EST) 02/19/2020 0/3 0/3 EVENT CLASSIFICATIONS 1-Hr. Non-Emergency 10 CFR 50.72(b)(1) (v)(A) Safe SID Capability AINA GENERAL EMERGENCY GENIAAEC TS Deviation ADEV (v)(B) RHR Capability AINB SITE AREA EMERGENCY SIT/AAEC 4-Hr. Non-Emergency 10 CFR 50.72(b)(2) (v)(C) Control of Rad Release AINC ALERT ALE/AAEC (i) TS Required S/D ASHU (v)(D) Accident Mitigation AIND 0 UNUSUAL EVENT UNU/AAEC (iv)(A) ECCS Discharge to RCS ACCS (xii) Offsite Medical AMED 50.72 NON-EMERGENCY (see next columns) (iv)(B) RPS Actuation (scram) ARPS (xiii) Loss Comm/Asmt/Resp ACOM PHYSICAL SECURITY (73 .71) DODD (xi) Offsite Notification APRE 60-Day Optional 10 CFR 50.73(a)(1)

MATERIAUEXPOSURE B??? 8-Hr. Non-Emen:iencv 10 CFR 50.72(b)(3) Invalid Specified System Actuation AINV FITNESS FOR DUTY HFIT (ii)(A) Degraded Condition ADEG Other Unspecified Requirement (Identify)

OTHER UNSPECIFIED REQMT. (see last column)

(ii)(B) Unanalyzed Condition AUNA NONR INFORMATION ONLY NINF (iv)(A) Specified System Actuation AESF NONR DESCRIPTION Include: Systems affected, actuations and their initiating signals, causes, effect of event on plant, actions taken or planned, etc. (Continue on back)

NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN CONTROL BUILDING At 0957 EST on February 19, 2020, a Notification of Unusual Event [NOUE] has been determined to be present at the Watts Bar plant Unit 1 under criteria HU4 for a fire potentially degrading the safety of the plant (fire for more than 15 minutes).

The NRC Senior Resident Inspector has been notified for this event.

Notified OHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), OHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • UPDATE ON 02/19/2020 AT 1151 EST FROM ANDREW WALDMANN TO DONALD NORWOOD* *

• The fire was declared extinguished at 1033 EST. The NOUE was terminated at 1126 EST. The investigation into the cause of the fire is in progress.

Notified R20O (Musser), NRR EO (Miller), and IRD MOC (Kennedy). Additionally, notified OHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), OHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • RETRACTION OF UNUSUAL EVENT NOTIFICATION***********************

Watts Bar Nuclear Plant (WBN) is retracting Event Notice 54531 (NOUE notification) based on the following additional information.

WBN reported a condition that was determined to meet the definition of a FIRE in the plant Emergency Preparedness Implementing Procedures (EPIP) based on indications available to the decision-maker at the time the declaration was made. A fire, without observation of flame, is considered present if large quantities of smoke and heat are observed. Moderate quantities of smoke were observed coming from an electrical cabinet not required to support safe plant operation. Once Fire Brigade personnel were able to access the affected room, no evidence of flame or significant heat was observed. Plant personnel ultimately determined that an overheated electrical component (transformer) resulted in the smoke. As such, the actual conditions did not meet the EPIP definition of a fire.

NOTIFICATIONS YES NO WILL BE ANYTHING UNUSUAL OR NOT UNDERSTOOD?

D YES (Ex plain above) 0 NO NRC RESIDENT 0 STATE(s)

--~ 0 DID ALL SYSTEMS 0 YES D NO (Explain above)

LOCAL _o_ 0 FUNCTION AS REQUIRED?

OTHER GOV AGENCIES

~

0 MODE OF OPERATION IESTIMATED I ADDITIONAL INFO ON BACK UNT IL CORRECTED: 3 RESTART DATE:

02/20/2020 YES NO MEDIA/PRESS RELEASE 0 (MM/DD/YYYY) 0 NRC FORM 361 (12-2000)

PAGE 1 OF 2 Page 25 of 29

NRC FORM 361 (12-2000) REACTOR PLANT EVENT NOTIFICATION WORKSHEET (CONTINUED)

ADDITIONAL INFORMATION RADIOLOGICAL RELEASES: CHECK OR FILL IN APPLICABLE ITEMS fsnecific d1>tailslexnlanations should be cover1>d in ev1>nt d<>ccrintinn l D LIQUID RELEASE IOI GASEOUS RELEASE D UNPLANNED RELEASE IOI PLANNED RELEASE ID ONGOING ID TERMINATED D MONITORED l I UNMONITORED D OFFSITE RELEASE lI T. S. EXCEEDED lo RM ALARMS ID AREAS EVACUATED D PERSONNEL EXPOSED OR CONTAMINATED D OFFSITE PROTECTIVE ACTIONS RECOMMENDED *state release path in description Release Rate {Ci/sec)  % T. S. LIMIT HOO GUIDE Total Activity (Ci)  % T. S. LIMIT HOO GUIDE Noble Gas 0 .1 Ci/sec 1000 Ci Iodine 10 uCi/sec 0.01 Ci Particulate 1 uCi/sec 1 mCi Liquid (excluding tritium and 10 uCilmin 0.1 Ci dissolved noble aases)

Liquid (tritium) 0.2 Ci/min 5 Ci Total PLANT STACK CONDENSER/AIR EJECTOR MAIN STEAM LINE SG SLOWDOWN OTHER RAD MONITOR READINGS ALARM SETPOINTS

% T. S. LIMIT(if applicable)

RCS OR SG TUBE L EAKS: CHECK OR FILL IN APPLICABLE ITEMS: (specific details/explanations should be covered in event description)

LOCATION OF THE LEAK (e.g., SG #, valve, pipe, etc.)

LEAK RATE UNITS: gpm/gpd T. S. LIM ITS SUDDEN OR LONG-TERM DEVELOPMENT LEAK START DATE TIME COOLANT ACTIVITY PRIMARY SECONDARY AND UNITS:

LIST OF SAFETY RELATED EQUIPMENT NOT OPERATIONAL EVENT DESCRIPTION (Continued from front)

NRC FORM 361 (12-2000) PAGE 2 OF 2 Page 26 of 29

From: RightFax E-mail Gateway Se nt: Fri, 29 Apr 2022 11:31:11 +0000 To: Hoc, HOO X

Subject:

A fax has arrived from remote ID".

Attachments: 00000689.PDF A fax has arrived from remote ID ".

4/29/2022 7:28: 11 AM Transmission Record Received from remote ID:

Inbound user JD HOO, routing code I 00 I Result: (0/352;0/0) Success Page record: I - 2 Elapsed time: 0 l :59 on channel 5 Page 27 of 29

MAR-28-2010 01:15 SE0UO'lAH r-lUC PL T P.01 j

Page 1 oti 1

-:i:,'

U.S. NUCLEAR REGULATORY COMMISSION APPROVEO 6Y 0MB: NO. 3150-(1238 EXPIRES 0/3112022 OPERATIONS CENTER Es~mated bu,den per ,esponse to comply with this volunlary colect10, ,equest: 30 minutes.

pr<>,-~ed w;11 be use:I for evaluat1D1 ol locoosee event 0<>=1pt1an, faallty status snd lo< input lo lh~

Sen:I oorarnents r,,gard1<*g bu,der eslornMe to !he lnf"""a~or se,.,,;ees Brn1ch (T-£ A 1OM), U.S.

REACTOR PLANT EVENT Gonw111ssIon, Washington, DC 2{]055*0~01. m t,y e-mail :o ln!ocollecis Besoorce@nn; """* and Office of 1nforrnaMn and RegLlato,;, A'fairs. NEOB-10202, (3150-0238). Offibo o!

NOTIFICATION WORKSHEET *.-,~ss,nglos, DC 20503 If~ me~ns usod 1o 1~ose ar 1nfovna!1on rolleci1on doa~llot display valid 0MB w**ul """'t,e,, \tie NRG ,n~y nul cooeucl u* sponso,. a*1d a parson ,snot 1equ(i"ed to ,aspond Womiat,oo collacimn.

EN# 55867 NRC OPERATIONS TELEPHONE NUMBERS* PRIMARY - 301-816-5100 or800-532-3469*, BACKUPS - [1st J 301-951-0550 o~B00-449-36~!

[2nd] 301-415-0550 and [3rd) 301-415--0553. 'Flicensees who maintain their own ETS are provided these lelephone numbers i, Ji ;

FAX- 301-816-5151, EMAIL* hoo.hoc@nrc.gov i  :-fil!

Notification Time FaclHty or Organization Unit Name of Callerfritle Call ljSack # :j!;

0704 4/29/2022 Sequoyah 1&2 Alton Crenshaw SRO/STA f423) 843~11 ,

Event Time & zone Event Date Power/Mode (At Time of Event) Power/Mode (At Time ~f Notification~;!

2338 Eastern 412812022 Both Units 100'% I Mode 1 Both Units 1100% . I Moij ,.., 1 l------*-v_e_NT_c_LA_s_s_,_.,_c_*_r_10_*_____+'-*"-"-*-"_o_*_-e_M_e_*_o_*_*_c_v_1_o_c_,_*_so_.,_20(b_Jc(1cJ-1-=='---c'*-1'--s-*_"_'_'°_"'_*c*_'_i1i1y'----'--" , AINA GENERAL EMERGENCY GE:NIAAEC TS Deviation ADEY (v)(B) RHR Capat,IJty  :~J :-*

SITE AREA EMERGENCY SITIAAEC 4-HR. NON-EMERGENCY 10 CFR 50.72(b)(2) M{C) Control of Rad Rnlease J\INC ALERT J\LEIAAEC (1) TS Kequired SIU ASHU D (v)(O) Accident M1l~at1on AIND UNUSUAL EVENT UNUIAAEC (1v)(A) ECCS 01setiarge to RCS ACCS (XII) Offsite Med1+,1 AMEO 0 50.72 NON-EMERGENCY {see next columns) D (iv){B) RPS Ac.ualion {scram) ARPS [Z] (xiii) Loss comm?Asmt/Respons~/i ACOM D PHYSICAL SE CUR In' (73.71) 0000 D (xi) Offsite Notification Ai'>RE 60-DAY OPTION410 CFR soj '~C.,):(:..C1J_-J D MATERIAUEXPOSURE 8??'/? 8-HR. NON-EMERGENCY 10 CFR 50.72(b)(3) 0 Invalid Spec;fied,$ystem Actuat~ij ; AINV FITNESS FOR DUn' <>IT (11)(A) Oegraded Condition AOEG OTHER UNSPECIFIED ~QUIREM~

1

&NTIFYW OTHER UNSPECIFIED REQMT. (see last column)

(ii}(B) Unanalyzed Condition AUNA  : i!J !: NOl'TI=

INFORMATION ONLY NNe

{IV)(A) Specified System Actuation AESe :1 NOOR Event Description (lriclude: Systems affected, actuat,ons "nd their imtiating signals causes, effect of event on pl,.nt, actions t"ken or planned, etc.}t(COfllinua on 2J On 4/28/2022 at 23:38 EST, Sequoyah received an unexpected alarm for seismological recording initiat8d At 23:41 EST, unexpected alarm 1/2 Safe Shutdown Earthquake response spectra exceeded wa!heceived~*T ,e National Earthquake Information Center was contacted to confirm there was no seismic activit)/, and this:V s also confirmed on the U.S. Geological Survey website. The alarms were determined to be invalid, a~d they o~'~ rred due to a failure in the seismic monitoring system. This failure results in loss of ability to assess~he Erner(:, ,., cy Action Leve! for Initiating Condition HU2 "Seismic event greater than Operating Basis Earthquake (OBEt 1 per procedure EPIP-1 "Emergency Plan Classification Matrix".  :.

~r

• ml *

~els"

• If an actual seismic event had occurred, HU2 could not be assessed. However, compensatoryr,easure~;, 've been implemented and include assessing OBE criteria based on alternative criteria contained ih procedJ" ,AOP~

N.05 "Earthquake" which provides conservative guidance when seismic instruments are unava:llable. /ii This is an eight hour, non-emergency notification for an event resulting in a major loss of Emerbency Assii:~:-l sment Capability. This event is reportable in accordance with 10 CFR 50.72{b)(3)(xiii). There is no impact on th:*.' :earth and safety of the public or plant personnel. The NRG Resident Inspector has been notified. 'j

!'i,,

1" NOTIFICATIONS v,s NO WJLL f--------+-ccc----+--c=-f-c"-iAnything Unusual " or not understood? D Yes (Explain abo..,e) (Zl No 0

NRC RESll)'l:NT STATE(s)

- + - + - - -

- < D i d all systems function as required? [ZJ Yes tJ No (Expl~ :above) 0 LOCAL ';'.,1 OTHER GOV AGENCIES 0 Mode of operntions until corrected (if applicable)

MEOIA/PRESS RELEASE 0

=::::::-'-=-...i...:aa:.....-=....._ Additional __ Information continued on next page?

_ _ _ _..;...;..___:;=----F-:-:-~ D Yes tzJ No NRC !=ORM 361 {02-2020) Continuooi next paga

• • c,_1 Page 28 of 29

MAR-28-20 10 01:15 SEQIJO"(AH r-llJC PL T P.02

...-- ----- ----- ----- ----- ----- ----- ---= ~*',)

NRC FORM 361 P!illge u.s. NUCLUR RE:GULATORY ~ ',- WISSION (02-2020)

OPERATIONS CENT~ilt:<

REACTOR PLANT EVENT NOTIFICATION WORKSHEET (Continued) ','

EN#

RADIOLOGICAL RELEASES: CHECK OR FILL IN APPLICABLE ITEMS (specific details/explanations should be covered in eventdescriptioll\l1 i 0 Liquid Release O Gaseous Release D Unplanned Release O Planned Release O Ongoing , 0 Temj1:, ":..,-,---!

D Monitored D Unmonilornd D Offsile Release O T.S. Exceeded D RM Alarms (; D Area1: ", ~eualtd D Per,;onnel Exposed or Contamirniled D Off,;ite Protection Aetions Recommended *state release paq) in descripti:

Release Rate (Ci/sec)  % T.S. Limit HOO Guide Total Activity (Ci) H uide Noble Gas 0.1 Cifsec Iodine 10 1,1Ci/sec Particulate 1 1,1Cifscc Liquid (excluding tritium and dissolved 10 1,1Ci/min ~ ,Ci

~"c'c'c1'~9c'c'l'-- --f---- -----+- ------- +------ --+---- ----f-- ---~--f ----;1-'

Liquid (tritium) 0.2 Cifmin '

TOTAL Plant Stack Condenser/Air Ejector Main Steam Line SG Slowdown t*

RAD Monitor Readings Alarm Setpoints

%~SL~tt(lf

~i applicable) l""';;;;;*ccc"s-o-.-.-.-T*u-.-.-,-EA-.-,-C_H_E_C_K_O,__R

\* !fl!'

. _F_I_L_L_IN_A_PcPcL-,-c-.-.-,-.-,T-E_M.....-,-(,-,p-,-,-,,.-,-.-,.-,-,,,-.-,-p-t,-n-,-tt-,*,,-,,-,-,-,-d-b-,-,-,-,-.,-,-,-,*,e,-,-.*"-,,-.-~-rl;;,, -J--i:1 Location of the Leak (e.g., SG #, valve, pipe, etc.)

Leak Rate Units: gpm/gpd T.S.Limits Sudden or Long-Term Development  ;, *1 I

~i

~Le:-,c,c::5:taCrtC::oC,:,.:---j~TCtm,:-,-------+-------,Pa,O;m:::,:,y:,1-------------;Se,::,::,:,c,:,y::--r,::----J:~' ei~-<1,f Coolant Activity 0 i*

and Units: \',

I List of Safety Relatefl Equipment not Operational NRC FORM 361 (02-2020)

TOTHL P.02 Page 29 of 29

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: "tholden@tnema.org": Lea. Edwin

Subject:

One EMERGENCY EVENT REPORT & another NON-EMERGENCY EVENT REPORT Date: Wednesday, March 09, 2016 7:19:00 AM Attachments: image00l.png

(

UnitcJ

/ U.S.NRC

\ta1 , udt' , R~ Jl,uo1y <omm,uion Proucti11K Peopl~ and 11,e E1wiro11mm1 Good morning Debra -

• At 0342 EST (0242 CST) this morning, Watts Bar Unit 2 declared an Notice of Unusual Event as the result of a fire greater than 15 minutes in duration. Plant personnel discovered smoke coming out of the 2B hotwell pump which is part of the system that condenses steam back to liquid water after it has passed through the generator turbine. The fire was extinguished at 0401 EST (0301 CST). The cause of the problem is under investigation. The plant was in Mode 5 (Shutdown). The plant has now exited the NOUE classification. There were no injuries nor were there any requests for offsite assistance. We are not aware of any media attention yet, but it is early.

• Late last week, NRC was notified that NFS received a package from Westinghouse in South Carolina with removable contamination in excess of DOT limits. The alpha (and beta/gamma) contamination measured 4278 dpm/100 sq. cm. and 6345 dpm/100 sq. cm ., respectively. The package was part of an exclusive use shipment. The package was successfully decontaminated, Westinghouse was notified, and NFS filed the required non-emergency event report with NRC. We learned of this yesterday.

As we learn more, or if we become aware of increased media attention, Edwin or I will be in touch.

Take care ...

John John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Office Cell#: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov Page 1 of 31

~ Please consider the environment before printing this e-mail. Thank you.

Power Reactor Event Number: 51780 Facility: WATTS BAR Notification Date: 03/09/2016 Region: 2 State: TN Notification Time: 04:01 [ET]

Unit: [] [2] [ ] Event Date: 03/09/2016 RX Type: [1] W-4-LP,[2] W-4-LP Event Time: 03:42 [EST]

NRC Notified By: BRIAN MCILNAY Last Update Date: 03/09/2016 HQ OPS Officer: VINCE KLCO Emergency Class: UNUSUAL EVENT Person (Organization):

10 CFR Section: LADONNA SUGGS (R2DO )

50.72(a) (1) (i) - EMERGENCY DECLARED CATHY HANEY (R2 )

JOHN LUBINSKI (NRR)

JEFFERY GRANT (IRD )

SCOTT MORRIS (NRR)

SCRAM RX Initial Current Unit Code CRIT PWR Initial RX Mode PWR Current RX Mode 2 N N 0 Cold Shutdown 0 Cold Shutdown Event Text UNUSUAL EVENT DECLARED DUE TO A FIRE GREATER THAN 15 MINUTES Watts Bar Unit 2 declared an Unusual Event at 0342 EST based on a fire greater than 15 minutes in the turbine building - 2B Hotwell pump motor. The fire was extinguished by 0401 EST, at the time of notification. Unit 2 is currently shutdown in Mode 5 making preparations for startup. No offsite assistance was requested. All personnel are accounted for and there are no personnel injuries reported.

The licensee notified the NRC Resident Inspector.

Notified DHS SWO, DOE, FEMA OPS, FEMA National Watch (email), DHS NICC, and Nuclear SSA (email).

• • • UPDATE AT 0512 ON 03/09/16 FROM BRIAN McILNAY TO S. SANDIN***

The licensee terminated the Unusual Event at 0508 EST based on verification that the fire was out and that the fire response team had been secured.

The licensee notified the State and local agencies and the NRC Resident Inspector.

Notified R2DO (Suggs), NRR EO (Morris) and IRD (Grant).

Notified DHS SWO, DOE, FEMA OPS, FEMA National Watch (email), DHS NICC, and Nuclear SSA (email).

Fuel Cycle Facility Event Number: 51767 Facility: NUCLEAR FUEL SERVICES INC. Notification Date: 03/04/2016 Page 2 of 31

RX Type: URANIUM FUEL FABRICATION Notification Time: 10:26 [ET]

Comments: HEU CONVERSION & SCRAP Event Date: 03/03/2016 RECOVERY Event Time: 21 :23 [EST]

NAVAL REACTOR FUEL CYCLE Last Update Date: 03/04/2016 LEU SCRAP RECOVERY Region: 2 City: ERWIN State: TN County: UNICOI License #: SNM-124 Agreement: Y Docket: 07000143 NRC Notified By: MICHAEL C. TESTER

. HQ OPS Officer: STEVE SANDIN Emergency Class: NON EMERGENCY Person (Organization):

10 CFR Section: MARVIN SYKES (R2DO) 20.1906(d)(l)- SURFACE CONTAM LEVELS > NMSS- EVENTS- NOTIFIC LIMITS (EMAI)

Event Text CONTAMINATED RADIOACTIVE MATERIAL SHIPMENT "On March 3, 2016, at approximately 1745 [EST], a radioactive material shipment was received at NFS from the Westinghouse Electric Company in Hopkins, South Carolina.

Receipt contamination and radiation sw-veys were completed at approximately 1905.

Results indicated removable sw-face contamination on two of the nine radioactive material packages that exceeded the criteria of the cited regulations.

"The radioactive material shipment left the Westinghouse Electric Company facility at 1300 [EST] on March 3, 2016. It was received at the NFS receiving facility at approximately 1745 on March 3, 2016. Surface contamination and radiation surveys were initiated immediately upon receipt. Removable surface contamination in excess of 10 CFR 20.1906(d) limits was verified to be present on the external surface of two of the nine shipping containers in the shipment at 1905. Contamination was controlled at the receiving facility and successfully decontaminated below criteria of 10 CFR 20.1906(d) by approximately 2030 on March 3, 2016."

This was an exclusive shipment. The alpha contamination measured 4278 dpm/ 100 sq. cm.

and 6345 dpm/100 sq. cm., respectively. The licensee informed Westinghouse who is conducting an investigation into this incident.

The licensee notified the NRC Resident Inspector.

Page 3 of 31

From: Pelchat. John To: Debra Shults [Debra Shults@tn gov}

Cc: Patrick Sheehan@tn gov: Lea Edwin

Subject:

NON-EMERGENCY EVENT REPORT

• Watts Bar Unit 1 Date: Thursday, December 21, 2017 12:00:00 PM Attachments: imaaeoo1 ooa

/ U.S.NRC l.:nntd \u1n ~udc.u Regub*ol) (*omrn~

Prouainx_ Ptopk 1111d ti~ E11viromn""'

Good morning Debra -

Yesterday TVA reported to N RC that at 1040 EST, an electrical board at Watts Bar Unit 1 experienced a fault. The design of the board interpreted the fault as a loss off site power, resulting in the startup of a number of auxiliary feedwater pumps to provide water to the steam generators, and the start of all four Emergency Diesel Generators (EDGs).

There was in fact, no loss of offsite power and Unit 1 continued to operate normally at full power.

Following troubleshooting, the plant's normal electrical configuration was restored by 1654 EST.

There were no injuries and there was no release of radioactive materials and the TVA continues to plant. This event had no impact on Unit 2 which was shutdown.

If you or anyone on your staff has any questions, please call Edwin or me.

Thanks and take care . . .

John John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission , Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Office Cell#: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov J.J Please consider the environment before printing this e-mail. Thank you.

SYSTEM ACTUATIONS DUE TO OPENING OF FEEDER BREAKER TO SHUTDOWN BOARD "On December 20, 2017, at 1040 Eastern Standard Time (EST), the Watts Bar Nuclear Plant (WBN) 1B-B 6.9kV Shutdown Board (SDBD) normal feeder breaker opened. The loss of voltage to the 1 B-8 SDBD resulted in the start of the 1B-B Motor Driven Auxiliary Feedwater (MDAFW) pump, the Unit 1 Turbine Driven Auxiliary Feedwater (TDAFW) pump, and the start of all four Emergency Diesel Generators (EDGs). Power was restored to the 1B-B 6.9 kV SDBD when it loaded on to its associated EDG.

"Following initial investigation , the 1B-B 6.9 kV SDBD was transferred to its alternate offsite power Page 4 of 31

source, Common Station Service Transformer (CSST) Cat 1217 EST. At 1230 EST, the 18-B 6.9 kV SDBD alternate feeder breaker opened. The loss of voltage to the 1B-B SDBD did not result in the restart of the 1B MDAFW pump, the Unit 1 TDAFW pump, or EDGs; this equipment remained running from the earlier event. Power was restored to the 18-8 6.9 kV SDBD when it loaded on to its associated EDG.

"Restoration of normal offsite power to the 1B-B SDBD was completed at 1654.

"Other than several common Unit Technical Specifications having not been met, Unit 2 was not operationally impacted by the transfer of the 1B-B Shutdown Board to onsite power and remains in Mode 1 at 100% power.

"This report is made per 10 CFR 50.72(b)(3)(iv)(A).

"NRG Resident Inspector has been notified."

The licensee investigation continues for the cause of the event.

Page 5 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: Patrjck.Sheehan@tn.gov: "anthony.hogan@tn.gov": "Andrew.Holcomb@tn.gov": tjm.holden@tn.gov: Lea. Edwin

Subject:

NON-EMERGENCY EVENT REPORT: Watts Bar Unit 2 Date: Monday, December 11, 2017 4:02:00 PM Good afternoon Debra -

TVA notified NRC at 0857 EST this morning (11 December 2017) that the Watts Bar Unit 2 reactor was manually tripped due to multiple dropped control rods. After the manual reactor trip, all control rods fully inserted. All safety systems functioned as designed including start-up of the three auxiliary feedwater pumps restore steam generator level.

Plant decay heat is being removed using the main condenser steam dumps.

The cause of the trip is being investigated. Since this event involved the actuation of the Reactor Protection System, it was reportable to NRC. There was no emergency declaration, no injuries, and no releases of radioactive materials.

If you have any question, please call Edwin or me.

Thanks and take care ...

John John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Office Cell#: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov

~ Please consider the environment before printing this e-mail. Thank you.

Page 6 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: "Andrew.Holcomb@tn.gov": Patrick Sheehan; Lea. Edwin

Subject:

NON EMERGENCY EVENT REPORT - Sequoyah Unit 1 Date: Monday, April 15, 2019 8:00:00 AM Attachments: image00l.png

(

UnitcJ

/ U.S.NRC

\ta1 , udt' , R~ Jl,uo1y <omm,uion Proucti11K Peopl~ and 11,e E1wiro11mm1 Good morning Debra At 3:14 Sunday morning, Sequoyah Unit 1 automatically tripped following the loss of a pump that feeds water into a steam generator. Plant systems continue to keep the core cool and safety systems operated as required. Details of the event are below.

Sequoyah Unit 2 was not impacted by this event.

Please call Edwin or me if you have any questions.

Take care ...

John John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Cell phone: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov

~ Please consider the environment before printing this e-mail. Thank you.

AUTOMATIC REACTOR TRIP DUE TO MAIN FEEDWATER PUMP TRIP At 0320 EDT, April 14, 2019, Sequoyah Unit 1 experienced an automatic reactor trip. The event was initiated by the trip of the 1A main feedwater pump. During the automatic unit run back, an automatic reactor trip was initiated due to low-low level in Steam Generator number 3.

"The Auxiliary Feedwater System (AFWS) automatically actuated as required when the expected post-trip feedwater isolation actuated. Reactor Coolant System temperature is being maintained by the AFWS and the steam dump system.

During this operational cycle, one control Rod Position Indicator (RPI) for core position E-5 in shutdown bank 'A' has been inoperable, and the appropriate Condition and Required Actions of [Technical Specification Limiting Condition of Operation] 3.1. 7 were complied with. Due to this inoperable RPI, the associated shutdown rod is conservatively assumed to be full out and untrippable. Consequently, boration was required to establish adequate shutdown margin. All other Control and Shutdown rods fully inserted. All safety systems responded as designed. No primary or secondary safety valves actuated during or after the Page 7 of 31

reactor trip. The unit is currently stable in Mode 3. Unit 1 is in a normal shutdown electrical alignment.

"There was no impact on Unit 2.

"Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system.

"There was no impact on the health and safety of the public or plant personnel.

"The NRC Senior Resident Inspector has been notified."

Page 8 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov): Brian Hastings Cc: Patrick Sheehan: "Pavid.Turberville@adph.state.al.us": kevin.hjcks@adph.state.al.us: nm Holden; Lea. Edwin:

Hecht. Randall; Ackermann. John <John.Ackermann@fema.dhs.gov); "Andrew Holcomb"

Subject:

NON-EMERGENCY EVENT REPORT

• Sequoyah, Browns Ferry and Watts Bar Date: Wednesday, November 13, 2019 7:49:00 AM Good morning -

EMERGENCY OPERATIONS FACILITY OUT OF SERVICE On November 12, 2019, the Central Emergency Control Center (CECC) was removed from service for a planned facility upgrade project. The CECC is a common Emergency Operations Facility (EOF) for the TVA Nuclear sites (Browns Ferry / Sequoyah / Watts Bar). The duration of the upgrade project is approximately 75 days.

If an emergency is declared requiring CECC activation during this period, an alternate CECC will be used. During this period, the alternate CECC will be staffed and activated using existing emergency procedures.

This is an eight-hour, non-emergency notification for a Loss of Emergency Assessment Capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii) because the CECC will be unavailable for more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

The Emergency Response Organization has been notified that the CECC will be unavailable during the upgrade project and to report to the alternate CECC in the event of an emergency. There is no impact on the health and safety of the public or plant employees.

The NRC Resident Inspector has been notified.

If you have any questions, please call us. Take care .. .

John John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Cell Phone: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov

~ Please consider the environment before printing this e-mail. Thank you.

Page 9 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: Lea. Edwin: Patrick Sheehan; "Andrew Holcomb": Tim Holden

Subject:

NON-EMERGENCY EVENT REPORT - Sequoyah Unit 1 Date: Wednesday, May 13, 2020 7:07:00 AM Good morning Debra -

AUTOMATIC REACTOR TRIP At 0208 EDT on 05/13/2020, Sequoyah Unit 1 was at 100% power when an automatic reactor trip signal was received concurrent with a low steam line pressure safety injection signal.

The low steam line pressure safety injection signal was actuated from the steam pressure rate of decrease feature. Main steam isolation valves (MSIVs) automatically closed as designed and steam generator pressures stabilized following the isolation. All other safety-related equipment operated as designed, with the exception of 1-FCV-61-122 Glycol inboard containment isolation valve which failed to automatically isolate on a Phase A containment isolation signal. The corresponding outboard containment isolation valve, 1-FCV-61-110, automatically isolated as designed which isolated penetration X-114.

Safety injection was terminated at 0221 EDT 5/13/20, and Unit 1 is currently being maintained in Mode 3 at normal operating temperature and pressure with auxiliary feedwater supplying the steam generators and decay heat removal via steam generator atmospheric relief valves.

There is no indication of any primary to secondary leakage. The electrical alignment is normal with shutdown power supplied from off-site power. There is no current operational impact to Unit 2.

There is no impact on public health or safety. Post safety injection actuation investigation is in progress.

If you have any questions, please call Edwin or me. Thanks and take care ...

John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Cell Phone: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov Web: www.nrc.gov Page 10 of 31

~ Please consider the environment before printing this e-mail. Thank you.

Page 11 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: Patrick Sheehan: "Andrew Holcomb": Kevin penney: Kevin petty: Lea. Edwin

Subject:

NON-EMERGENCY EVENT REPORT - Watts Bar Units 1 & 2 Date: Tuesday, June 23, 2020 7:05:00 AM Good morning Debra -

OFFSITE NOTIFICATION - GROUNDWATER INITIATIVE At 1304 EDT on June 22, 2020, Watts Bar Nuclear Plant (WBN) Units 1 and 2 initiated voluntary communication to the State of Tennessee and local officials as part of the Nuclear Energy Institute (NEI) Groundwater Protection Initiative (GPI), after receiving analysis results for one on-site monitoring well that indicated tritium activity above the GPI voluntary communication threshold. WBN identified and corrected the cause.

This condition did not exceed any NRC regulations or reporting criteria. This notification is being made solely as a four-hour, nonemergency notification for a Notification of Other Government Agency. This event is reportable in accordance with 10 CFR 50.72(b)(2)(xi).

There was no impact on the health and safety of the public or plant personnel.

Please call Edwin or me if you or your staff have questions. Thanks and take care ...

John John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Cell Phone: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc,goy Web: www.nrc.gov

~ Please consider the environment before printing this e-mail. Thank you .

Page 12 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: Patrjck.Sheehan@tn.gov: Andrew Holcomb - Tennessee Department Of Environment And Conseryatjon (andrew.holcomb@tn.gov): Tim.Holden@tn.gov; Kevin Penney; Kevin Petty: Lea. Edwin

Subject:

NON-EMERGENCY EVENT REPORT: Sequoyah Date: Monday, November 02, 2020 6:12:00 AM Attachments: imaaeO0l.ooa Good morning Debra -

LOSS OF SEISMIC ASSESSMENT INSTRUMENTATION At 0556 EST on 11/01/2020, Sequoyah received unexpected alarms for seismological recording initiated and [Units] 1/2 Safe Shutdown Earthquake response spectra exceeded. No seismic event was felt on site, the National Earthquake Information Center was contacted to confirm there was no seismic activity, and this was also confirmed on the U.S. Geological Survey website. The alarms were determined to be invalid, and they occurred due to a failure in the seismic monitoring system. This failure results in loss of ability to assess the Emergency Action Level for Initiating Condition HU2 'Seismic event greater than Operating Basis Earthquake (OBE) levels' per procedure EPIP-1 .

If an actual seismic event occurred, HU2 could not be assessed. However, compensatory measures have been implemented and include assessing OBE criteria based on alternative criteria contained in procedure AOP-N.05 Earthquake' which provides conservative guidance when seismic instruments are unavailable.

This is an eight hour, non-emergency notification for an event resulting in a major loss of Emergency Assessment Capability. This event is reportable in accordance with 10 CFR 50.72(b)(3)(xiii). There is no impact on the health and safety of the public or plant personnel.

As always, please call Edwin or myself if you have any questions. Take care ...

John John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Cell Phone: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov Web: www.nrc.gov "Anyone can stay the same. It takes courage to change." - John Assaraf Page 13 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: BiUy.Freeman@tn.gov: Patrick Sheehan: Jim.Holden@tn.gov: Kevin petty: Kevin Penney

Subject:

NON-EMERGENCY EVENT REPORT - Sequoyah Unit 1 Date: Tuesday, May 25, 2021 7:35:00 AM Attachments: image001.png Good morning Debra, On 5/24/21 at 0916 EDT, an Automatic Reactor Trip on Sequoyah Unit 1 occurred. All safety systems responded normally, and the plant is currently stable in Mode 3 (Hot Standby) at normal operating temperature and pressure. Preliminary indications are that the unit trip was caused by a High Neutron Flux Rate detected by the Power Range Nuclear Instruments. No relief valves opened. All Rods fully inserted. Decay heat is being removed by Auxiliary Feedwater via the steam dumps. The plant is in a normal post-trip electrical line-up.

Troubleshooting and investigation are ongoing to determine the initiating cause.

Unit 2 was not impacted and remains stable in Mode 1 at 100 percent power.

Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B) and in accordance with 10 CFR 50.72 (b){3)(iv)(A) as an event that results in a valid actuation of the AFW system.

There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspectors are following the licensee's investigation.

If you have any questions, please call Edwin or me. Thanks and take care . . .

jp John M. Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Cell Phone: 404-819-6455 FAX: 404-997-4901 E-mail: john.pelchat@nrc.gov Web: www.nrc.gov "Anyone can stay the same. It takes courage to change." - John Assaraf

1. courageforchange Page 14 of 31

From: Pelchat John To: Debra Shults !Debra.Shults@tn.gov)

Cc: Patrick Sheehan: beth.sheJton@tn.gov: Iim,Holden@tn.gov: "Andrew.Holcomb@tn.gov"; Kevin Penney: Kevin eettv; Tim.Holden@tn.gov; Wells. Kevin; Ackermann. John

Subject:

NON-EMERGENCY EVENT REPORT . Sequoyah Date: Thursday, February 17, 2022 7:36:00 AM Attachments: imaae002.ona Good morning (again)

LOSS OF OFFSITE COMMUNICATION CAPABILITY The following information was provided by the licensee:

At 1128 EST on 2/16/2022, the SON [Sequoyah Nuclear) Shift Manager was notified that TVA [Tennessee Valley Authority] attempted to notify Tennessee Emergency Management Agency (TEMA) regarding routine siren testing at 0750. TVA was unable to reach TEMA via telephone land line or the Emergency Communication and Notification System (ECNS). TEMA Watch Point staff were located at their back-up facility. TVA subsequently notified TEMA via cell phone that there were communication issues with the primary and backup notification methods. It was determined that the TEMA back-up facility was not able to receive incoming calls. At 0820, TEMA positioned personnel at their primary facility in order to respond to notifications. This restored primary and backup means of notifying the state because the primary facility was not affected by the communication issues.

This event is reportable in accordance with 10 CFR 50. 72(b )(3)(xiii) as a Major Loss of Offsite Communications Capability because it affected TVA's ability to notify the State of TN .

Please call me if you have any questions. Take care ...

john John M . Pelchat Senior Regional Government Liaison Officer U.S. Nuclear Regulatory Commission, Region II 245 Peachtree Center Avenue, NE, Suite 1200 Atlanta, Georgia 30303-1257 Telephone: 404-997-4427 Cell Phone: 404-819-6455 FAX: 404-997-4901 E-mail: john,pelchat@nrc.gov Web: www.nrc.gov "Anyone can stay the same. It takes courage to change." - John Assaraf

1. courageforchange Page 15 of 31

From: Bjshop. Brad To: Carman. Paul Cc: Smith. Steven

Subject:

Bullets about the NOEDs Date: Friday, July 22, 2022 9 :07:24 AM Hey Paul, These are our concise notes for the 2 emergent issues we had this week. I have more details if you'd like but Laura said she didn't want too much detail. I'll update you if anything changes.

Surry U1 #1 EOG emergency repairs:

• During the monthly run of the #1 EOG on 7/ 18, the generator experienced an unexpected loss of load.

• The EOG was removed from service and troubleshooting discovered a ground in the generator rotor field.

• 7 day TS LCO to return the #1 EOG to service expires Monday 7/25 at 0956.

Installation of a new generator is in progress. PMT will follow installation.

• The timeline for return to service is projected to be Sunday at noon.

Sequoyah U1 18 Charging pump emergent repairs:

• On 07/18 TVA Sequoyah Unit 1 declared the 1B Charging pump inoperable, entering a 72-hour shutdown LCO.

• Maintenance is currently in progress with return to service expected on 7/24.

• TVA has requested an ASME Code alternative request under 10 CFR 50.55a(z)

(2), Hardship, from the required post maintenance testing as well as a request for a Notice of Enforcement Discretion (NOED) to provide additional time to affect the necessary corrective maintenance.

• The NRC has provided verbal approval of the alternative request as well as enforcement discretion for Sequoyah Unit 1 from TS 3.5.2 Action A for an additional 69 hours7.986111e-4 days <br />0.0192 hours <br />1.140873e-4 weeks <br />2.62545e-5 months <br /> beyond 7/21 at 2230.

Brad Page 16 of 31

From: Masters Anthony To: Haney. Catherine: Munday. Joel: Franke. Mark Cc: Cook. Christopher; Pelchat. John; Hannah. Roger: Seat. Jamin

Subject:

FYI - SQN plans to retract NOUE Date: Monday, November 26, 2018 10:59:00 AM Importance: High Just a very quick FYI to inform you that SQN has confirmed the source of the smoke from some hydraulic fluid that leaked onto insulation in the PZR enclosure. They are reporting that no actual alarms signaled in the control room and the smoke was identified by someone in the field observing the smoke and reporting it to the control room. They plan to retract the NOUE as it no longer meets their criteria. The news media and fire departments have left the site.

More details in an email from the Senior Resident Inspector will be forthcoming shortly, but I just wanted to get this out to calm any concerns of this while we are awaiting the more detailed summary.

Anthony D. Masters, PE Chief, Reactor Projects Branch 5 Division Reactor Projects (DRP)

U.S. Nuclear Regulatory Commission Region 11- Atlanta 404 997 - 4465 (office phone) b)(6) (cell phone)

(404) 997 - 4905 (fax)

Anthony Masters@nrc.gov Page 17 of 31

Table 1: Decision Documentation for Reactive Inspection (Deterministic and Risk Criteria Analyzed)

MD 8.3 20-002 PLANT: Watts Bar U1 I EVENT DATE: 02/19/2020 I EVALUATION DATE:02/25/2020 Brief Description of the Significant Operational Event or Degraded Condition:

On February 19, 2020 at 0935, while operating at 100% power, the Watts Bar Unit 1 reactor experienced a manual reactor trip in response to the #3 Main Feedwater regulating valve (MFRV) to steam generator #3 being in manual with 100% output and level in #3 S/G lowering uncontrolled.

Based on the results of their troubleshooting plan and internal operating experience, the licensee determined that the failure of the #3 MFRV was caused by a stuck pushbutton on the Loop 3 controller which was driving the valve in the closed direction.

This failure caused the main feedwater regulating valve to not maintain steam generator level requiring Operators to initiate a manual Reactor Trip with follow on Turbine Trip.

All control and shutdown bank rods inserted properly in response to the reactor trip. All safety systems including the Auxiliary Feedwater (AFW) System actuated in response to the trip, as expected. All systems actuated as required and there were no complications with the trip.

However, following the trip at 0938 there was a report of heavy smoke in the 250-volt battery board room causing the licensee to enter a Notification of Unusual Event at 0957.

Residents responded to the control room and fire brigade assembly area to follow both the trip response and the potential fire response.

At 0959 the Incident Commander declared that no visible flame was present.

Unit 1 was stabilized in Mode 3, and Unit 2 was unaffected and remained at 100% rated thermal power throughout the event.

The NOUE was exited at 1126 and then was retracted on 2/20/2020@ 1453. This retraction was made because no flame was observed upon entry into the room which is one of the criteria required to meet the definition of a FIRE in the plant Emergency Preparedness Implementing Procedures (EPIP). The licensee also determined that the amount of smoke present was consistent with an overheated transformer.

The room that the overheated transformer was in is a room that houses non-safety I non-risk significant loads.

The licensee theorizes that an electrical transient happened as a result of the plant swapping non-safety loads from the output of the generator to the offsite power supply and this caused the transformer to overheat.

The initial findings from the licensee suggested that the contacts "stuck or froze". This was not the case, the licensee sent the controller off to their central lab for failure analysis and the central lab determined the contacts were working properly, so the most likely cause was the plastic on plastic parts of the push button stuck and the operators didn't realize it.

Enclosure Page 18 of 31

Y/N DETERMINISTIC CRITERIA N a. Involved operations that exceeded, or were not included in, the design bases of the facility Remarks: This event was not a design basis issue.

N b. Involved a major deficiency in design, construction, or operation having potential generic safety implications Remarks: Did not involve a major deficiency.

N c. Led to a significant loss of integrity of the fuel, primary coolant pressure boundary, or primary containment boundary of a nuclear reactor Remarks: No boundaries impacted.

N d. Led to the loss of a safety function or multiple failures in systems used to mitigate an actual event Remarks: All safety systems performed as designed.

N e. Involved possible adverse generic implications Remarks: The licensee initially thought this could have been a generic issue with the controller. Follow up analysis by their central labs determined that the issue was most likely a stuck pushbutton that was unrecognized by the operator. The controller and associated 12arts are non-safety related.

N f . Involved significant unexpected system interactions Remarks: Did not involve a significant unexpected system interaction. All systems responded as expected.

N g. Involved repetitive failures or events involving safety-related equipment or deficiencies in operations Remarks: This event did not involve repetitive failures or events involving safety-related equipment or deficiencies in operations.

N h. Involved questions or concerns pertaining to licensee operational performance Remarks: Did not involve concerns pertaining to licensee operational performance.

Enclosure Page 19 of 31

I CONDITIONAL RISK ASSESSMENT I RISK ANALYSIS BY: Not needed because DATE:

deterministic criteria not met.

Brief Description of the Basis for the Assessment (may include assumptions, calculations, references, peer review, or comparison with licensee=s results):

The licensee did a PRA assessment for the Unit 1 Trip. They determined the following as part of their assessment:

• The change in Core Damage Frequency (CDF) was (9.078E 9.0?SE-06) =3.2E-09.

• The change in LERF was (1.1194E 1.1193E-06) =1.0E-10.

• These values represent the incremental conditional core damage probability and large early release probability associated with the trip and they are considered very small.

The estimated conditional core damage probability (CCDP) is and places the risk in the range of a and inspection.

I RESPONSE DECISION I USING THE ABOVE INFORMATION AND OTHER KEY ELEMENTS OF CONSIDERATION AS APPROPRIATE, DOCUMENT THE RESPONSE DECISION TO THE EVENT OR CONDITION,

~ND THE BASIS FOR THAT DECISION DECISION AND DETAILS OF THE BASIS FOR THE DECISION:

!This was an uncomplicated reactor trip and involved a potential non-safety related MFRG controller defect. Therefore, it does not meet the MD 8.3 deterministic criteria. The generic implication for MD 8.3 only applies if there is an effect on nuclear safety related equipment

!Which performs safety function, not for a non-safety related component. Recommend a routine resident baseline inspection to follow up the issue.

BRANCH CH IEF REVIEW: DAT E:

Thomas A. Stephen, Chief RPBS DRP February 26, 2020 Page 20 of 31

DIVISION DIRECTOR REV~ W k ar S* M*11 Oigitallysig ned byMark S. Miller DATE:

I er Date, 2020.02 .26 135 4'42

• 0S'OO' ADAMS ACCESSION NUMBER:

EVENT NOTIFICATION REPORT NUMBER (as applicable):

E-mail to NRR ReactivelnsoectionNRC.GOV Page 21 of 31

From: Childs Natasha To: Masters. Anthony Cc: seat. Jamin: Deschaine. Wesley: Hardage. David

Subject:

NOUE at Sequoyah Date: Monday, November 26, 2018 12:02:00 PM Attachments: image002.png At 08:03 this morning (with Unit 2 in Mode 5 and pressurizer bubble established, no RCPs running), the Unit 2 Control Room received a report from the field of visible smoke in the Unit 2 raceway. The source was not known at that time (could not verify whether source was from inside or outside polar crane wall) . Unit 2 entered AOP-N.01 , Plant Fires (for a reported fire reported OR other valid indications of fire). At 08:07, offsite fire assistance (Soddy Daisy Fire Dept) was requested; offsite fire assistance arrived onsite (outside of the PA) and were available to support. When offsite fire assistance was requested, the news media was notified through radio traffic. The shift manager declared a NOUE based on EAL HU4 (text from HU4 pasted below). Channel 9 news was present onsite (outside of PA) shortly after the NOUE was declared.

Some of the immediate actions included securing all ventilation and running equipment inside containment (except lighting) to refute those items as potential sources of smoke.

Smoke was reported in lower and upper containment. At 09:27 fire brigade personnel confirmed the source of the smoke to be from the pressurizer enclosure. The operations director was informed that a hydraulic line had previously been blown off during installation and torqueing of the pressurizer manway in the days prior (estimated 4 ounces of spilled oil). The hydraulic oil had apparently leaked down in between the metal and mirror insulation of the pressurizer. With a flash point of 410 deg F, it is postulated that the hydraulic oil started to smoke once temperatures rose above 410 deg F. The pressurizer temperature was estimated to be around 428 deg Fat the time of the report of smoke.

Once the licensee was able to cool the pressurizer down below 410 deg F, they were able to remove the manway enclosure and access the interior of the enclosure. Personnel confirmed that there was no visible fire inside of the enclosure and that the source of smoke was spilled hydraulic oil that had not been adequately cleaned up previously. At 10:29 reports from the field were that smoke was no longer present in lower or upper containment. The shift manager terminated the NOUE at 10:36. The Acting Senior Resident continues to monitor the licensee's actions surrounding this event.

Other Notes

• The licensee plans to retract the NOUE based on the fact that there was no "alarm" of the fire and that there was not an actual "fire" condition. There had been some initial miscommunication that there was a fire alarm.

• The licensee plans to make an 8-hour notification to the NRC based on the media interest in this event

• Requesting offsite fire assistance is normal practice for Sequoyah so that the onsite fire brigade can focus on the ongoing fire and offsite fire assistance would be staged and ready for any other fires that might occur anywhere else onsite.

• Licensee continues to investigate the reported oil spill amount and whether the use of hydraulic tools is appropriate for the application Natasha Childs Page 22 of 31

USNRC Senior Resident Inspector (Acting)

Sequoyah Nuclear Plant (423) 842-8001 Page 23 of 31

HU4 ECL: Unusual Event Initiating Condition: FIRE potentially degrading the level of safety of the plant.

Operating Mode Applicability: All Emergency Action Levels: (1 or 2 or 3 or 4)

Note: The SEO should declare the Unusual Event promptly upon determining that the applicable time has been exceeded. or will likely be exceeded.

(1) a. A FIRE is NOT extinguished within 15-minutes of ANY of the following FIRE detection indications:

• Report from the field (that is, visual observation)

• Receipt of multiple (more than 1) fire alarms or indications

• Field verification of a single fire alarm AND

b. The FIRE is located within ANY of the Table H2 plant rooms or areas.

OR (2) a. Receipt of a single fire alarm (that is, no other indications of a FIRE).

AND

b. The FIRE is located within ANY of the Table H2 plant rooms or areas.

AND

c. The existence of a FIRE is not verified within 30-minutes of alarm receipt.

OR (3) A Fl RE within the plant PROTECTED AREA not extinguished within 60-minutes of the initial report, alarm or indication.

OR (4) A FIRE within the plant PROTECTED AREA that requires firefighting support by an offsite fire response agency to extinguish.

Table H2-Flre Areas Reactor Building ERCVvPump House Auxiliary Buildina Control Buildinq Turbine Building Diesel Generator Bldgs.

Page 24 of 31

From: Childs Natasha To: Suggs. LaDonna Cc: Miller. Mark: Hardage. Dayjd: Stephen. Tom; McKown. Lou;s: Taylor. Ryan: Ninh. Son

Subject:

RE: [Response Requested] Draft Email Comm for SEQ NOUE Date: Friday, April 29, 2022 4:46:44 AM Attachments: image00l.png Update ...

The licensee has terminated the NOUE at 04:06 based on their conclusion that the event was caused by instrumentation failure and not an actual event. They will most likely retract the NOUE. The licensee is also evaluating whether 50.72 reporting, related to loss of assessment capability is applicable due to the failed instrument channel.

I'm headed home for the morning. Dave should be onsite in a couple of hours and can follow any other activities related to the NOUE.

From: Childs, Natasha Sent: Friday, April 29, 2022 4:29 AM To: Suggs, LaDonna <LaDonna.Suggs@nrc.gov>

Cc: M iller, Mark <M ark.Mil ler@nrc.gov>; Ha rdage, David <David .Hardage@nrc.gov>

Subject:

RE: [Response Requested] Draft Email Comm for SEQ NOUE

LaDonna, My revision is below. Sorry it took so long. The licensee has concluded that the event was caused by an instrument failure and not an actual earthquake (see below). They plan to exit the NOUE. Feel free to revise as needed.

All-Please see below for a brief description of the Sequoyah Unit 1 and 2 Notification of Unusual Event declared at 23:55 EST on Thursday, April 28, 2022.

Event Facts and Summary On April 28, 2022, at 23:38, the Unit 1 main control room received an unexpected annunciator on panel 1-XA-55-15B, window D-1 (Seismological Recording Initiated). At 23:41 , a second unexpected annunciator was received on window E-2 of panel 1-XA-55-15B (1/2 SSE Response Spectra Exceeded). Ground motion was not felt in the main control room; however, one security officer on-site did report feeling movement in their BRE and mentioned hearing a sound similar to thunder or a rock quarry detonation in the distance. The licensee referenced the US Geological Survey Website and contacted the Earthquake Information Center with no reported indications of earthquake activity. No other plant systems or areas were noted as being affected or damaged. Both units were and remain at 100% power.

Licensee Response At 23:55 EST, April 28, 2022, Sequoyah declared a Notification of Unusual Event Page 25 of 31

(NOUE) due to a seismic event as indicated by seismic annunciators in the Unit 1 main control room and ground motion sensed by security personnel (emergency action level (EAL) HU2, Seismic event greater than OBE levels). At 23:56, both units entered AOP-N.05, Earthquake, which contains steps to perform damage assessment and check the validity of seismic indications. On April 29, 2022, the licensee made notifications to the state of Tennessee at 00:05 and the NRC Headquarters Operations Officer (HOO) at 00:19 EST. The monitoring instruments that feed into the 0-1 and E-2 annunciators are located in the Unit 1 Containment Building, so the licensee also proceeded with a containment entry at approximately 04:00 to inspect the seismic instrumentation and the surrounding areas. In accordance with Step 22 of AOP-N.05, the licensee evaluated the need to shutdown

/ cooldown the units to mode 5. Troubleshooting activities and engineering review of the response spectra analysis revealed that channel 2 on the XT-52-75B accelerometer was failed ; channel 2 was the only channel out of three that indicated movement on the seismic report. Civil engineering reported that the graphs from the seismic report were not indicative of an actual earthquake. The licensee concluded that the event was caused by instrumentation failure and not an actual event and plans to take steps to exit the NOUE based on this updated information.

Additionally, the licensee will conduct a fatigue assessment of the individual who reported feeling ground motion and hearing an explosion in the distance.

NRC Response The Resident Inspector (Natasha Childs) responded to the plant. She reported to the control room and verified the licensee's emergency declaration and the licensee's initial response actions. The NRC remained in Normal Response Mode throughout the event.

From: Suggs, LaDonna <LaDonna.Suggs@nrc.gov>

Sent: Frid ay, April 29, 2022 1 :42 AM To: Childs, Natasha <Natasha .Ch ilds@nrc.gov>

Cc: Ha rdage, David <David Hardage@nrc gov>; Miller, M ark

Subject:

[Response Req uested] Draft Ema il Comm for SEQ NOUE Natasha -

Thanks so much for your responsiveness to the site. As we await your assessment and update, I started a draft summary communication from the info provided during the blast dial w/ the HOO to get us started ... please review and modify as appropriate with the latest information ... Once I have your update, we'll send a communication forward to ORA and the principles, including OEOO for their morning meetings.

All-Please see below for a brief description of the Sequoyah Unit 1 and 2Notice of Unusual Event declared at 0019 Friday April 29th.

Page 26 of 31

Event Facts and Summary At 12:19am EST, April 29, 2022, Sequoyah Units 1 and 2 declared a Notice of Unusual Event (NOUE) due to earthquake detected by seismic instruments (panel alarm) and ground motion sensed by plant personnel (Emergency Action Level (EAL) H.U.2). A seismic alarm was received in the control room and plant security indicated feeling ground motion. Additionally, a security guard noted possibly hearing an explosion in the distance.

No motion was felt inside the control room. No other plant systems or areas were noted as being affected. Both units were and remain at 100% power.

Licensee Response At 12:19am EST, Sequoyah declared a Notice of Unusual Event due to earthquake detected by seismic instruments (panel alarm) and ground motion sensed by plant personnel (Emergency Action Level (EAL) H.U.2). The licensee made notifications to the state. At 12:19am EST, the licensee notified the NRC Headquarters Operations Officer (HOO). Licensee operators entered abnormal operating procedures which require plant shutdown. Prior to commencing any shutdown activities the licensee conducted an analysis to determine if there was an actual seismic event. The licensee noted a single accelerometer inside containment as the sole indication with no other accelerometers alarming.

NRC Response The Senior Resident Inspector (Natasha Childs) responded to the plant. She verified the licensee's emergency declaration and the licensee's initial response actions. Currently the NRG remains in Normal Response Mode and will continue to monitor plant conditions.

llfan11es117..egardr, LaDonna B. Suggs I Deputy Director, Division of Reactor Projects - RII / DRP U.S. Nuclear Regulatory Commission - RII I 245 Peachtree Center Ave. NE ISuite 1200 I Atlanta, GA 30303 lirD: 404.997.4501 1!J,f: 404.997.45151 21: LaDonna.Suggs@nrc.gov I www.nrc.gov Page 27 of 31

From: Suggs, LaQonna To: Dudes. Laura; Pelton, Dayjd; Veil, Andrea: King, Mike: Pelchat. John: Screnci, Diane: Gaspersoo, Dave; Orlikowski. Robert Cc: Suggs, LaDonna: Franke. Mark; Pearson, Laura: Stephen, Tom; Childs, Natasha: Hardage. David; Taylor, Ryan:

Ninh Son; McKown Louis: Eatmon, Gwynne

Subject:

Sequoyah Unit 1 and 2 Notice of Unusual Event Date: Friday, April 29, 2022 5:54:53 AM Attachments: iooaaeoo1.ona Good Morning All -

Please see below for a brief description of the Sequoyah Unit 1 and 2 Notice of Unusual Event declared t his morning (Friday) April 29t h.

Event Facts and Summary On Apri l 28, 2022, at 23:38, the Unit 1 main control room received an unexpected annunciator on pa nel 1-XA-55-lSB, w indow D-1 (Seismological Recording Initiat ed). At 23:41, a second unexpect ed annu nciator was received on window E-2 of panel 1-XA-55-15B (1/2 SSE Response Spectra Exceeded). Ground motion was not felt in the main control room; however, one secu rity officer on-site did report feel ing movement in their guard station (BRE) and mentioned hearing a sound similar t o thunder or a rock quarry detonation in t he dist ance. The licensee referenced t he US Geological Survey Website and contacted the Earthquake Information Center with no reported ind ications of earthquake activity. No other plant systems or areas were noted as being affected or damaged.

Both units were and rema in at 100% power.

Licensee Response At 23:55 EST, Apri l 28, 2022, Sequoyah declared a Notification of Unusual Event (NOUE) due to a seismic event as indicated by seismic an nunciators in the Unit 1 main cont rol room and ground motion sensed by security personnel (emergency action level (EAL) HU2, Seismic event greater than Operating Basis Earthq uake (OBE) leve ls). At 23:56, both units entered AOP-N.05, Earthquake, which contains steps to perform damage assessments and check the validity of seismic indications. On April 29, 2022, the licensee made not ificat ions t o the state of Tennessee at 00:05 and the NRC Headq uarters Operations Officer (HOO) at 00:19 EST. The monitoring instruments for t he annunciators are located in the Unit 1 Contai nment Buildi ng, so the licensee entered containment at approximately 04:00 to inspect the seismic instrumentation and the surround ing areas. In accordance wit h response procedures, t he licensee evaluated the need to shutdown/ cooldown t he units to Mode 5. Troubleshooting activities and engineering review of the response spect ra analysis revealed that channel 2 on the XT-52-75B accelerometer was fai led; channel 2 was the only channel out of three that indicated movement on t he seismic report. Civil engineering reported that the graphs from t he seismic report were not indicative of an act ual eart hq uake. The licensee terminated the NOUE at 04:06 based on their concl usion t hat t he event was caused by instrumentation fail ure and not an actual event. They are also considering retracting the NOUE based on the concl usion.

Additionally, t he licensee is evaluating whether 50.72 reporting, related to loss of assessment capabilit y is applicable due to the fa iled inst rument channel. The licensee wi ll also conduct a fa tigue assessment of t he individual who reported feeli ng ground motion and hearing an explosion in t he Page 28 of 31

distance.

NRC Response Seq uoyah Resident Inspector (Natasha Chi lds) responded to the plant. She reported to the control room and verified plant stabi lity, t he licensee's emergency declaration and the licensee's initial response actions. The NRC rema ined in Norma l Response Mode t hroughout t he event and both Seq uoyah Resident Inspectors wil l cont inue to monit or the licensee's activit ies related to t he event .

ff:7ar111est Regards,

~. ' _;

LaDonna B. Suggs I Deputy Director, Division of Reactor Projects - RII / DRP U.S. Nuclear Regulatory Commission - Rll j 245 Peachtree Center Ave. NE !Suite 1200 I Atlanta, GA 30303

~ D: 404.997.4501 J ~ F: 404.997.45151 21: LaDonna.Suggs@nrc.gov I www.nrc .gov Page 29 of 31

From: Hoc, HOO X To: Hoc HOO X

Subject:

HOO Highlight: SEQUOYAH - NOUE Date: Friday, April 29, 2022 1: 16:44 AM Information contained in this email is pre-decisional and for internal use only . If you have any questions, please contact the NRC Operations Center.

On 04/28/22, at 2355 EDT, w ith both Sequoyah Unit 1 and 2 in Mode-1, 100 percent, a Notice of Unusual Event was declared due to receiving two seismic alarms and security feeling ground movement. Additionally, security in a tower heard an explosion. Both units remain in Mode-1, 100 percent and they are investigating the validity of the seismic alarms before proceeding with the Abnormal Operating Procedure required shutdown.

The NRC remains in the Normal mode of operations.

Headq uarters Operations Officer U.S. Nuclear Regu latory Commiss ion Phone: 301-816-5100 Fax : 301-816-5151 email: hoo.hoc@nrc.gov secure email: hool@nrc sgov,gov Page 30 of 31

From: Hoc, HOO X To: Hoc HOO X

Subject:

HOO Highlight: SEQUOYAH - Termination of NOUE Date: Friday, April 29, 2022 4:59:17 AM Information contained in this email is pre-decisional and for internal use only . If you have any questions, please contact the NRC Operations Center.

On 4-29-22, at 0406 EDT, Sequoyah Unit 1 and Unit 2 terminated the Notice of Unusual Event. The Civil Engineers determined that the alarms were due to a failed seismic indicator channel. Through interviews, only one security officer felt ground movement for a couple of seconds and heard a faint rumbling sound. A fatigue assessment is being performed on the security officer.

The NRC remains in the Normal mode of operations.

Headquarters Operations Officer U.S. Nuclear Regu latory Commission Phone: 301-816-5100 Fax: 301-816-5151 email: hoo. hoc@nrc.gov secure email: hool@nrc.sgov gov

/ U.S. RC

\ tJ\ *'- ~

• o-t l-*

'F,,,,,.,.-,1#1 r,.p1, """ ,& p.,.,.,,.,..,.,,,;

Page 31 of 31

From: Childs Natasha To: Masters. Anthony Cc: seat. Jamin: Hardage. David

Subject:

Keeping Current - Teams Respond to Reports of Smoke Inside Unit 2 Containment Building.pdf Date: Monday, November 26, 2018 1:31:00 PM Attachments: Keeping Current - Teams Respond to Reports of Smoke Inside Unit 2 Containment Buildinq.pdf FYI ... see attached. Also, the licensee is about to make their 4-hour notification to NRC regarding the media interest in the event. They will send me a copy of the notification shortly.

Page 1 of 2

SEQUOYAH Keeping Current [i!lJ November 26, 2018 Teams Respond to Reports of Smoke Inside Unit 2 Containment Building Earlier this morning, SON Fire Operations responded to a report of smoke in the Unit 2 Containment Building. At 0816, Sequoyah's Shift Manager declared a notification of unusual event (NOUE) for Unit 2. An NOUE is the lowest of four emergency classification levels.

No flames were ever visible at any point prior to, or during the NOUE. At 1000 this morning, the Fire Operations team was stood down.

At 1036, Sequoyah exited the NOUE. After investigation, the smoke was determined to be caused by oil that had leaked from a hydraulic tool onto the Unit 2 Pressurizer, inside Unit 2 Containment. The hot surface of the Pressurizer heated the oil ,

causing it to smoke.

At no time was there any risk to plant personnel, equipment or the public, and there have been no reports of damage to any equipment. TVA Fire Service and SQN Fire Ops personnel responding to the NOUE at SQN today, after light Radiation Protection has reported no abnormal conditions inside smoke was reported inside the Unit 2 Containment. The Unit 2 reactor is unaffected and the reactor Containment Building. Plant personnel are safe, remains in a safe configuration. Work inside Containment was with no reports of damage to any equipment.

stopped during the NOUE, and will resume shortly.

Unit 2 continues safely in its planned refueling outage, with Unit 1 unaffected and running at 100% power.

"Today's event is an example of why we place focus on emergency preparedness," said Plant Manager Matt Rasmussen. "Our Fire Operations personnel and Operations team responded exactly how we needed them to do so-quickly, by procedure and with control. Reports were made in a timely manner, and the plant was maintained in a safe, stable condition. We're thankful that this wasn't an actual event, and are proud of the way our teams responded."

We are now in the process of retracting the NOUE declaration, after validation that there was no fire.

Questions? Speak with your supervisor.

Please refer any media inquiries on this event to our TVA media team at 865-632-6000 or tvainfo@tva.gov.

NOTICE: This electronic message transmission contains information which may be TVA SENSITIVE, TVA RESTRICTED or TVA CONFIDENTIAL. Any misuse or unauthorized disclosure can result in both civil and criminal penalties. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the content of this information is prohibited. If you have received this communication in error, please notify me immediately by email and delete the original message.

Page 2 of 2

Information from RPS-Oversight Issue ID 20123 Issue Details EDIT ISSUE UNUSUAL EVENT DECLARED FOR EXCESSIVE SMOKE IN CONTAINMENT Issue ID 20123 Created 11/27/2018 Screened 11/27/2018 Last Updated 11/27/2018 Sources EN Region Region 2 Dockets Sequoyah 2 PN #

None IRS Report None Components None Systems None Comm Groups None TRGs EP, FIRE PROTECTION, CONTAINMENT INPO Doc None Other Document None Final Disposition Sent to TRG, INES Level 0 EN Info Event Date 11/26/2018 Submitted Date Page 1 of 3 Page 1 of 34

Information from RPS-Oversight Issue ID 20123 11/26/2018 EN Number 53754 Event Description Power Reactor Notes None Description UNUSUAL EVENT DECLARED FOR EXCESSIVE SMOKE IN CONTAINMENT At 0816 EST, a Notification of Unusual Event was declared for Unit 2 under Emergency Action Level H.U.4 for excessive smoke in the lower level of containment with a heat signal. Onsite fire brigade is responding to the event. A command post is established. Offsite support is requested by the fire brigade. No flames have been observed as of this report.

The NRC Resident Inspector and State and Local government agencies will be notified.

Notified DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• UPDATE ON 11/26/18 AT 1036 EST FROM BILL HARRIS TO JEFFREY WHITED***

At 1036 EST, Sequoyah Nuclear Station Unit 2 terminated the Notice of Unusual Event. The licensee determined that the source of the smoke in containment was oil on the pressurizer beneath the insulation, that heated up during plant heatup. The licensee did not see visible flame during the event. The licensee is still working to determine if there was any damage to the pressurizer.

The licensee will notify the NRC Resident Inspector.

Notified R2DO (Rose), R2RA (Haney), NRR (Nieh), IRD MOC (Gott), DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • UPDATE ON 11/26/18 AT 1337 EST FROM STEPHEN FRIESE TO KARL DIEDERICH***

Page 2 of 3 Page 2 of 34

Information from RPS-Oversight Issue ID 20123 Following declaration of the Notification of Unusual Event, TVA media relations communicated with the local media regarding the event.

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Rose).

• • • UPDATE ON 11/26/18 AT 1551 EST FROM STEPHEN FRIESE TO DONG PARK * **

"At 1036 EDT, Sequoyah Nuclear Plant (SQN) terminated the Notification Of Unusual Event (NOUE) due to initial report of heat and smoke in Unit 2 Lower Containment.

"At 1000 EDT, it was determined that no fire had occurred. Due to difficulty of access to some of the areas being searched, the source could not be identified prior to 1000 EDT. No visible flame (heat or light) was observed.

"The source of the smoke was determined to be residual oil from a hydraulic tool oil in contact with pressurizer piping. The pressurizer piping was being heated up to support Unit 2 start-up following U2R22 refueling outage. Once the residual oil dissipated, the smoke stopped. It has been concluded that no fire or emergency condition existed.

"Unit 2 is currently in Mode 5, maintaining reactor coolant temperature 160F-170F and pressure 325psig-350psig with 2A Residual Heat Removal (RHR) system in service in accordance with U2R22 refueling outage plan."

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Rose).

Page 3 of 3 Page 3 of 34

Information from RPS-Oversight Issue ID 20155 Issue Details EDIT ISSUE Retraction - UNUSUAL EVENT DECLARED FOR EXCESSIVE SMOKE IN CONTAINMENT Issue ID 20155 Created 11/30/2018 Screened 12/03/2018 Last Updated 12/03/2018 Sources EN Region Region 2 Dockets Sequoyah 2 PN #

None IRS Report None Components None Systems None Comm Groups None TRGs EP, FIRE PROTECTION, CONTAINMENT INPO Doc None Other Document None Final Disposition Sent to TRG EN Info Event Date 11/26/2018 Page 1 of 4 Page 4 of 34

Information from RPS-Oversight Issue ID 20155 Submitted Date 11/26/2018 EN Number 53754 Event Description Power Reactor Notes None Description Date screened: 11/27/2018 EN Revision Imported Date: 11/30/2018 EN Revision Text: UNUSUAL EVENT DECLARED FOR EXCESSIVE SMOKE IN CONTAINMENT At 0816 EST, a Notification of Unusual Event was declared for Unit 2 under Emergency Action Level H.U.4 for excessive smoke in the lower level of containment with a heat signal. Onsite fire brigade is responding to the event. A command post is established. Offsite support is requested by the fire brigade. No flames have been observed as of this report.

The NRC Resident Inspector and State and Local government agencies will be notified.

Notified DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • UPDATE ON 11/26/18 AT 1036 EST FROM BILL HARRIS TO JEFFREY WHITED***

At 1036 EST, Sequoyah Nuclear Station Unit 2 terminated the Notice of Unusual Event. The licensee determined that the source of the smoke in containment was oil on the pressurizer beneath the insulation, that heated up during plant heatup. The licensee did not see visible flame during the event. The licensee is still working to determine if there was any damage to the pressurizer.

The licensee will notify the NRC Resident Inspector.

Page 2 of 4 Page 5 of 34

Information from RPS-Oversight Issue ID 20155 Notified R2DO (Rose), R2RA (Haney), NRR (Nieh), IRD MOC (Gott), DHS SWO, FEMA Operations Center, DHS NICC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • UPDATE ON 11/26/18 AT 1337 EST FROM STEPHEN FRIESE TO KARL DIEDERICH***

Following declaration of the Notification of Unusual Event, TVA media relations communicated with the local media regarding the event.

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Rose).

• • • UPDATE ON 11/26/18 AT 1551 EST FROM STEPHEN FRIESE TO DONG PARK***

"At 1036 EDT, Sequoyah Nuclear Plant (SQN) terminated the Notification Of Unusual Event (NOUE) due to initial report of heat and smoke in Unit 2 Lower Containment.

"At 1000 EDT, it was determined that no fire had occurred. Due to difficulty of access to some of the areas being searched, the source could not be identified prior to 1000 EDT. No visible flame (heat or light) was observed.

"The source of the smoke was determined to be residual oil from a hydraulic tool oil in contact with pressurizer piping. The pressurizer piping was being heated up to support Unit 2 start-up following U2R22 refueling outage. Once the residual oil dissipated, the smoke stopped. It has been concluded that no fire or emergency condition existed.

"Unit 2 is currently in Mode 5, maintaining reactor coolant temperature 160F-170F and pressure 32Spsig-350psig with 2A Residual Heat Removal (RHR) system in service in accordance w ith U2R22 refueling outage plan."

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Rose).

Page 3 of 4 Page 6 of 34

Information from RPS-Oversight Issue ID 20155

• *

• RETRACTION ON 11/29/2018 AT 1358 EST FROM FRANCIS DECAMBRA TO ANDREW WAUGH *

"Sequoyah Nuclear Plant (SQN) is retracting this notification based on the following additional information not available at the time of the notification:

"Following a full Reactor Building inspection, it was concluded that a fire did not exist. The source of the smoke originally reported was later determined to be residual oil from a hydraulic tool in contact with pressurizer piping. Once the residual oil dissipated, the smoke stopped. The source of heat originally reported was normal heated conditions associated with the pressurizer commensurate with plant conditions. SQN reported initially based on the available information at the time and to ensure timeliness with emergency declaration and reporting notification requirements."

The licensee has notified the NRC Resident Inspector.

Notified R2DO (Shaeffer).

Page 4 of 4 Page 7 of 34

Information from RPS-Oversight Issue ID 24329 Issue Details EDIT ISSUE Retraction - NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN CONTROL BUILDING Issue ID 24329 Created 02/21/2020 Screened 02/24/2020 Last Updated 02/24/2020 Sources EN Region Region 2, Region 2 Dockets Watts Bar 1, Watts Bar 2 PN #

None IRS Report None Components None Systems None Comm Groups None TRGs l&C, FIRE PROTECTION, Electrical Power, EP INPO Doc None Other Document None Final Disposition Sent to TRG, INES Level 0 EN Info Event Date 2/19/2020 Page 1 of 3 Page 8 of 34

Information from RPS-Oversight Issue ID 24329 Submitted Date 2/19/2020 EN Number 54531 Event Description Power Reactor Notes None Description Date screened: 2/20/2020 EN Revision Imported Date: 2/21/2020 EN Revision Text: NOTIFICATION OF UNUSUAL EVENT DUE TO FIRE IN CONTROL BUILDING "At 0957 EST on February 19, 2020, a Notification of Unusual Event [NOUE] has been determined to be present at the Watts Bar plant Unit 1 under criteria HU4 for a fire potentially degrading the safety of the plant (fire for more than 15 minutes).

"The NRC Senior Resident Inspector has been notified for this event."

Notified DHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

• • • UPDATE ON 02/19/2020 AT 1151 EST FROM ANDREW WALDMANN TO DONALD NORWOOD*

The fire was declared extinguished at 1033 EST. The NOUE was terminated at 1126 EST. The investigation into the cause of the fire is in progress.

Notified R2DO (Musser), NRR EO (Miller), and IRD MOC (Kennedy). Additionally, notified DHS SWO, FEMA Operations Center, CISA IOCC, FEMA NWC (email), DHS Nuclear SSA (email), and FEMA NRCC SASC (email).

Page 2 of 3 Page 9 of 34

Information from RPS-Oversight Issue ID 24329

• • • RETRACTION ON 2/20/2020 AT 1453 EST FROM MICHAEL BUTHEY TO RICHARD L. SMITH***

"Watts Bar Nuclear Plant (WBN) is retracting Event Notice 54531 (NOUE notification) based on the following additional information.

"WBN reported a condition that was determined to meet the definition of a FIRE in the plant Emergency Preparedness Implementing Procedures (EPIP) based on indications available to the decision-maker at the time the declaration was made. A fire, without observation of flame, is considered present if large quantities of smoke and heat are observed.

"Moderate quantities of smoke were observed coming from an electrical cabinet not required to support safe plant operation. Once Fire Brigade personnel were able to access the affected room, no evidence of flame or significant heat was observed. Plant personnel ultimately determined that an overheated electrical component (transformer) resulted in the smoke. As such, the actual conditions did not meet the EPIP definition of a fire."

The NRC Resident Inspector has been notified of this retraction.

Notified R2D0 (Musser), NRR EO (Miller), and IRD MOC (Kennedy).

Page 3 of 3 Page 10 of 34

From: Hoc. HOO X To: Hoc. HOO X

Subject:

HOO Highlight: SEQUOYAH - NOUE Date: Friday, April 29, 2022 1: 16:44 AM Information contained in this email is pre-decisional and for internal use only. If you have any questions, please contact the NRC Operations Center.

On 04/28/22, at 2355 EDT, with both Sequoyah Unit 1 and 2 in Mode-1, 100 percent, a Notice of Unusual Event was declared due to receiving two seismic alarms and security feeling ground movement. Additionally, security in a tower heard an explosion. Both units remain in Mode-1, 100 percent and they are investigating the validity of the seismic alarms before proceeding with the Abnormal Operating Procedure required shutdown.

The NRC remains in the Normal mode of operations.

Headquarters Operations Officer U.S. Nuclear Regulatory Commission Phone: 301-816-5100 Fax: 301-816-5151 email: hoo.hoc@ nrc.gov secure email: hoo1@nrc.sgov.gov

"'U.S. RC t ""' ' . ..,c "'

Pr,uai111 rt.pk "'"' ,h, ,:,,,.,...,.,,.,,,

Page 11 of 34

From: Hoc. HOO X To: Hoc. HOO X

Subject:

HOO Highlight: SEQUOYAH - Termination of NOUE Date: Friday, April 29, 2022 4:59: 17 AM Information contained in this email is pre-decisional and for internal use only. If you have any questions, please contact the NRC Operations Center.

On 4-29-22, at 0406 EDT, Sequoyah Unit 1 and Unit 2 terminated the Notice of Unusual Event. The Civil Engineers determined that the alarms were due to a failed seismic indicator channel. Through interviews, only one security officer felt ground movement for a couple of seconds and heard a faint rumbling sound. A fatigue assessment is being performed on the security officer.

The NRC remains in the Normal mode of operations.

Headquarters Operations Officer U.S. Nuclear Regulatory Commission Phone: 301-816-5100 Fax: 301-816-5151 email: hoo.hoc@ nrc.gov secure email : hool@nrc.sgov gov t ,J\. ' .. ...,u...

l'rotl'UJl'f. l.,.p/, 111<1/ ,/;, F.,,ri,.IM'ffl Page 12 of 34

Information from RPS-Oversight Issue ID 29405 Issue Details EDIT ISSUE Retraction - NOTICE OF UNUSUAL EVENT Issue ID 29405 Created 04/29/2022 Screened 05/03/2022 Last Updated 05/03/2022 Sources EN Region Region 2, Region 2 Dockets Sequoyah 1, Sequoyah 2 PN #

None IRS Report None Components None Systems None Comm Groups None TRGs OTHER, l&C, EP Emails: Kevin.Quinlan@nrc.gov, David.Heeszel@nrc.gov INPO Doc None Other Document None Final Disposition Sent to TRG, INES Level 0 EN Info Event Date 4/28/2022 Page 1 of 4 Page 13 of 34

Information from RPS-Oversight Issue ID 29405 Submitted Date 4/30/2022 EN Number 55866 Event Description Power Reactor Notes From RII NITA on 4/29/2022:

At 23:55 EST, April 28, 2022, Sequoyah declared a Notification of Unusual Event (NOUE) due to a seismic event as indicated by seismic annunciators in the Unit 1 main control room and ground motion sensed by security personnel (emergency action level (EAL) HU2, Seismic event greater than Operating Basis Earthquake (OBE) levels). At 23:56, both units entered AOP-N.05, Earthquake, which contains steps to perform damage assessments and check the validity of seismic indications. Troubleshooting activities and engineering review of the response spectra analysis revealed that channel 2 on the XT-52-75B accelerometer was failed; channel 2 was the only channel out of three that indicated movement on the seismic report. Civil engineering reported that the graphs from the seismic report were not indicative of an actual earthquake. The licensee terminated the NOUE at 04:06 based on their conclusion that the event was caused by instrumentation failure and not an actual event. The licensee conducted a fatigue assessment of the individual who reported feeling ground motion (no impairment noted).

Description Date Originally Screened: 5/2/2022 EN Revision Imported Date: 5/3/2022 EN Revision Text: NOTICE OF UNUSUAL EVENT The following is a summary of information provided by the licensee via telephone:

On 04/28/22, at 2355 EDT, with both Sequoyah Unit 1 and 2 in Mode- 1, 100 percent, a Notice of Unusual Event was declared due to receiving two seismic alarms and security feeling ground movement. Additionally, security in a tower heard an explosion. Both units remain in Mode- 1, 100 percent and they are investigating the validity of the seismic alarms before proceeding with the Abnormal Operating Procedure required shutdown.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRC Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Page 2 of 4 Page 14 of 34

Information from RPS-Oversight Issue ID 29405 Notified DHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), OHS NRCC THO Desk(email), and DHS Nuclear SSA (email).

• • • UPDATE ON 04/29/2022 AT 0410 EDT FROM BRIAN KLEIN TO OSSY FONT***

The following is a summary of information provided by the licensee via telephone:

On 4/29/22, at 0406 EDT, Sequoyah Unit 1 and Unit 2 terminated the Notice of Unusual Event. The Civil Engineers determined that the alarms were due to a failed seismic indicator channel. Through interviews, only one security officer felt ground movement for a couple of seconds and heard a faint rumbling sound.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRC Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Notified R2DO (Miller), NRR EO (Miller), and IR MOC (Gott) via email.

Additionally, notified OHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), OHS NRCC THO Desk(email), and DHS Nuclear SSA (email).

• • • RETRACTION ON 05/02/2022 AT 2118 EDT FROM SCOTT SEAL TO LLOYD DESOTELL * *

• The following information was provided by the licensee via email:

"SQN [Sequoyah Nuclear Plant] is retracting the previous NOUE [Notice of Unusual Event]

declaration made on 4/28/22 at 2355 [EDT] based on Emergency Action Level HU2 for a seismic event greater than Operating Basis Earthquake levels. Following the declaration of the NOUE, the station reviewed all available indications and determined that a seismic event had not occurred. The instrumentation failure was documented under Event Notification #55867."

Page 3 of 4 Page 15 of 34

Information from RPS-Oversight Issue ID 29405 Notified R2D0 (Mi ller), and IR MOC (Gott), NRR EO (Miller) via email.

Page 4 of 4 Page 16 of 34

From: nita@nrc gov To: Winslow. Julie

Subject:

NITA - R2-DRP BC report archived - automated email Date: Sunday, May 1, 2022 8:52:45 PM Attachments: 13il..odf To: Winslow, Julie From: NITA Application RE: Branch Chief Report created A Branch Chief report has been archived in organizational unit R2-DRP. If you would like to view this report online it can be accessed here.

Note: This mailbox is not monitored.

Page 17 of 34

RA Report United States NUCLEAR REGULATORY COMMISSION Region II 245 Peachtree Center Avenue N.E., Suite 1200 Atlanta, GA 30303-1257 April 29, 2022 MEMORANDUM TO: Laura A. Dudes, Regional Administrator FROM: Mark Miller Director, Division of Reactor Projects

SUBJECT:

R2-DRP WEEKLY ACTIVITY REPORT Significant activities completed by R2-DRP during the week ending April 29, 2022, and those planned for the next week are summarized below. Additional details regarding significant activities and operational issues can be obtained through the NRC Issues Tracking Application (NITA).

1. Significant accomplishments/activities this week

• Senior Project Engineer (SPE) Matthew Toth supported a biennial graded exercise for Framatome in Richland, WA.

• Joe Austin , Catawba Senior Resident Inspector (SRI), responded to the site following a manual reactor trip of Unit 2 that occurred on Saturday, April 23. The licensee tripped the reactor following two dropped rods that occurred during rod movement testing. The failure of an auxiliary steam supply valve resulted in a loss of condenser vacuum following the reactor trip . The auxiliary feedwater system (AFW) actuated and steam generator (S/G) power operated relief valves (PORVs) were used to provide decay heat removal. An MD 8.3 evaluation was completed and no additional inspection was recommended.

• David Rivard, Catawba resident inspector (RI), monitored the licensee's restart of Unit 2 on Tuesday, April 26.

• Chris Safouri, Vogtle Unit 1&2 SRI hosted Robert Feitel, Inspector General; Edward O'Connell, Chief of Staff; Michael Clark, General Counsel; Malion Bartley, Assistant Inspector General for Investigations; Chris Arroyo, Communications Officer; Terri Spicher, Team Leader - Assistant; for a site familiarization visit on April 28, 2022.

• Andy Hutto and Christian Scott, McGuire residents, will monitor the licensee's startup activities this weekend, following the Unit 1 refueling outage.

• Jared Nadel, Adam Ruh, and Nick Smalley, Oconee residents, will monitor the licensee's shutdown activities over the weekend, as Unit 3 enters its refueling outage .

• SRI Mac Read attended Leadership training at PDC

• SRI Matt Endress was selected as Acting Branch Chief (BC) for RPB4 and started on Monday April 25th.

• SPE Jeff Hamman performed/led the prep week for next week's Problem Identification and Resolution (PIR) inspection at the St Lucie plant.

• Emergency Preparedness Inspector Jacqwan Walker completed a 5 month rotation at the Robinson plant. Jacqwan was a significant help to the branch and SRI.

• On April 27th, RPB4 conducted the annual assessment meeting for Brunswick and Harris.

• Larry Jones, Senior Reactor Inspector, provided resident inspector on-site support at North Anna.

• A design basis assurance inspection (DBAI) team led by Theo Fanelli, Senior Reactor Inspector, completed their 2nd week of on-site inspection at Harris .

• A DBAI team led by Chase Franklin, Reactor Inspector, completed their 1st week of on-site inspection at Brunswick.

• At 23:55 EST, April 28, 2022, Sequoyah declared a Notification of Unusual Event (NOUE) due to a Page 1 of 2 Page 18 of 34

RA Report seismic event as indicated by seismic annunciators in the Unit 1 main control room and ground motion sensed by security personnel (emergency action level (EAL) HU2, Seismic event greater than Operating Basis Earthquake (OBE) levels). At 23:56, both units entered AOP-N.05, Earthquake, which contains steps to perform damage assessments and check the validity of seismic indications.

Troubleshooting activities and engineering review of the response spectra analysis revealed that channel 2 on the XT-52-75B accelerometer was failed; channel 2 was the only channel out of three that indicated movement on the seismic report. Civil engineering reported that the graphs from the seismic report were not indicative of an actual earthquake. The licensee terminated the NOUE at 04:06 based on their conclusion that the event was caused by instrumentation failure and not an actual event. The licensee conducted a fatigue assessment of the individual who reported feeling ground motion (no impairment noted). Sequoyah RI Natasha Childs responded to the plant and verified the licensee's initial response actions.

2. Significant activities planned for next week

• On May 3rd, the resident inspectors and RPB3 regional staff will present the Annual Assessment meeting for the Next Era / FPL plants

• On May 5th SRI Mac Read and the RPB3 regional staff will present a hybrid in-person and virtual Annual Assessment meeting for the VC Summer plant

• On May 2nd, the resident inspectors at Harris plant will support a visit from Commissioner Wright.

3. Inspection program implementation issues, site coverage, qualifications/training

• Zack Hollcraft, Senior Reactor Operations Engineer, Division of Reactor Oversight, provided resident backfill at Vogtle Unit 1&2.

• Lundy Pressley (NRR) provided Oconee resident backfill support the week of 4/25.

• Frank Young, Branch 1 project engineer/resident inspector development program (RIDP), is participating in the Westinghouse R-624P simulator course at the TTC the weeks of 4/25 and 5/2.

• Christian Scott, McGuire RI, completed Westinghouse refresher training at the TTC the week of 4/25.

• RIDP Derrick Jung starts a site rotation for development at the VC Summer plant with SRI Mac Read

• Kevin Pfeil, Branch 4 RIDP, spent the week on-site at North Anna for training.

cc: L. Dudes D. Pelton M. Franke L. Suggs R2-DRP Page 2 of 2 Page 19 of 34

From: NRR PRO IOEB Resource@nrc goy To: Winslow. Julie

Subject:

IOEB Clearinghouse Screening Summary for Monday, May 2, 2022 Date: Monday, May 2, 2022 1:47:54 PM Total Issues: 6 NOTE: THIS

SUMMARY

IS FOR OFFICIAL USE ONLY

• • MAY CONTAIN SENSITIVE/PROPRIETARY OR NRC INTERNAL USE ONLY INFORMATION**

DO NOT FORWARD ANY PORTIONS OUTSIDE OF NRC WITHOUT FIRST OBTAINING PERMISSION FROM ORIGINATOR (Note - The infonnation in this part of the Summary is often preliminary in nature and is provided to help IOEB staff communicate and track noteworthy items being followed up by either the Regions or HQ staff.]

1) EN (55866) - Sequoyah 1, Sequoyah 2 - NOTICE OF UNUSUAL EVENT Open in RPS-Oversight Screening Level: Level 1 Notes:

From RII NITA on 4/29/2022:

At 23:55 EST, April 28, 2022, Sequoyah declared a Notification of Unusual Event (NOUE) due to a seismic event as indicated by seismic annunciators in the Unit 1 main control room and ground motion sensed by security personnel (emergency action leve l (EAL) HU2, Seismic event greater than Operating Basis Earthquake (OBE) levels). At 23:56, both units entered AOP-N.05, Earthquake, which contains steps to perfonn damage assessments and check the validity of seismic indications. Troubleshooting activities and engineering review of the response spectra analysis revealed that channel 2 on the XT-52-75B accelerometer was failed; channel 2 was the only channel out of three that indicated movement on the seismic report. Civil engineering reported that the graphs from the seismic report were not indicative of an actual earthquake. The licensee terminated the NOUE at 04:06 based on their conclusion that the event was caused by instrumentation failure and not an actual event. The licensee conducted a fatigue assessment of the individual who reported feeling ground motion (no impairment noted).

==

Description:==

NOTICE OF UNUSUAL EVENT The following is a summary of information provided by the licensee via telephone:

Page 20 of 34

On 04/28/22, at 2355 EDT, with both Sequoyah Unit land 2 in Mode-1, 100 percent, a Notice of Unusual Event was declared due to receiving two seismic alarms and security feeling ground movement. Additionally, security in a tower heard an explosion. Both units remain in Mode-1, 100 percent and they are investigating the validity of the seismic alarms before proceeding with the Abnormal Operating Procedure required shutdown.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRC Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Notified DHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), OHS NRCC THD Desk(email), and OHS Nuclear SSA (email).

• • • UPDATE ON 04/29/2022 AT 0410 EDT FROM BRIAN KLEIN TO OSSY FONT***

The following is a summary of information provided by the licensee via telephone:

On 4/29/22, at 0406 EDT, Sequoyah Unit 1 and Unit 2 terminated the Notice of Unusual Event. The Civil Engineers determined that the alarms were due to a failed seismic indicator channel. Through interviews, only one security officer felt ground movement for a couple of seconds and heard a faint rumbling sound.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRC Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Notified R2DO (Miller), NRR EO (Miller), and IR MOC (Gott) via email.

Page 21 of 34

Additionally, notified DHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), DHS NRCC THD Desk(email), and DHS Nuclear SSA (email).

ML Number:

Sent to:

OTHER - Kevin.Quinlan@nrc.gov, David.Heeszel@nrc.gov I&C- DXK4@nrc.gov EP - Jonathan.Fiske@nrc.gov

2) EN (55857) - Byron 2 - EN Revision Imported Date:

5/2/2022 EN Revision Text: ULTRASONIC EXAMINATION RESULTS - REACTOR VESSEL HEAD PENETRATION Open in RPS-Oversight Screening Level: Level 1 Notes:

==

Description:==

EN Revision Imported Date: 5/2/2022 EN Revision Text: ULTRASONIC EXAMINATION RESULTS - REACTOR VESSEL HEAD PENETRATION The following information was provided by the licensee via email:

"At 0854 [CDT] on April 23, 2022, while performing volumetric inspections required by ASME Code Case N-729-6, a rejectable indication on Reactor Vessel Head Penetration 75 Core Exit Thermocouple (CETC) was identified. The indication is located inboard of the J-groove weld and is OD-initiated [outer diameter - initiated]. This event is being repo1ied as an eight-hour, non-emergency notification per 10 CFR 50.72(b)(3)(ii)(A).

"There was no impact on the health and safety of the public or plant personnel. The NRC Page 22 of 34

Resident Inspector has been notified."

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The repair is scheduled during the refueling outage.

• * *UPDATE ON 04/29/22 AT 1112 EDT FROM BRYAN L YKKEBAK TO OSSY FONT The following information was provided by the licensee via telephone and email:

"The rejectable indication on Reactor Vessel Head Penetration 75 Core Exit Thermocouple (CETC) initiated on the outside diameter (OD) of the nozzle in an area that was not smface stress mitigated (peened). The indication was found to be acceptable for continued operation under CFR and ASME requirements and will not be repaired during this outage.

"The licensee notified the NRC Resident Inspector."

Notified R3DO (Ziolkowski).

ML Number:

Sent to:

PRI MATLNSL/WELD - john.tsao@nrc.gov NRO - Michael.Webb@nrc.gov

3) EN (55867) - Sequoyah 1, Sequoyah 2 - LOSS OF ASSESSMENT CAPABILITY Open in RPS-Oversight Screening Level: Level 1 Page 23 of 34

Notes:

==

Description:==

LOSS OF ASSESSMENT CAPABILITY The following information was provided by the licensee via fax:

"On 4/28/2022, at 2338 EDT, Sequoyah received an unexpected alarm for seismological recording initiated. At 2341 EDT, unexpected alarm 1/2 Safe Shutdown Earthquake response spectra exceeded was received. The National Earthquake Information Center was contacted to confinn there was no seismic activity, and this was also confim1ed on the U.S. Geological Survey website. The alarms were determined to be invalid, and they occurred due to a failure in the seismic monitoring system. This failure results in loss of ability to assess the Emergency Action Level for Initiating Condition HU2 'Seismic event greater than Operating Basis Earthquake (OBE) levels' per procedure EPIP-1, 'Emergency Plan Classification Matrix.'

"If an actual seismic event had occurred, HU2 could not be assessed. However, compensatory measures have been implemented and include assessing OBE criteria based on alternative criteria contained in procedure AOP-N.05, 'Earthquake,' which provides conservative guidance when seismic instruments are unavailable.

"This is an eight-hour, non-emergency notification for an event resulting in a major loss of Emergency Assessment Capability. This event is reportable in accordance with 10 CFR

50. 72(b)(3)(xiii). There is no impact on the health and safety of the public or plant personnel.

The NRC Resident Inspector has been notified."

The following additional infonnation was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The faulty detector was removed from service, so the remaining detector provides conservative detection as the only source to make-up the logic for a seismological alarm.

ML Number:

Sent to:

OTHER- Kevin.Quinlan@nrc.gov, David.Heeszel@nrc.gov EP - Jonathan.Fiske@nrc.gov I&C- DXK4@nrc.gov Page 24 of 34

4) EN (55868) - Harris 1 - MANUAL REACTOR TRIP AND AUXILIARY FEEDWATER SYSTEM ACTUATION Open in RPS-Oversight Screening Level: Level 1 Notes:

UPDATE From RII NITA on 5/2/2022:

Harris restarted over the weekend from the 4/29 manual reactor trip on degraded condenser vacuum due to the B condenser vacuum pump (CVP) suction valve (lAE-16) failure to auto close when the pump was secured while swapping to the A CVP. No major equipment problems or operator performance issues occurred during the restart activities.

?The licensee was unable to identify the reason why the B CVP suction valve failed to auto close that created the degrading vacuum condition. Troubleshooting confirmed there was no mechanical issue with the valve, it was stroked multiple times over the weekend with no issues. Also, no issues were identified with the logic and electrical circuitry, and the failure was not repeatable. Currently, the A CVP is in service and will remain in service through the current month's equipment rotation period. Troubleshooting testing verified that the auto-open function of the suction valve when the B CVP gets a low vacuum start signal was still reliable (in a situation where the running A CVP could suddenly fail). Going forward, the licensee still plans to conduct the monthly swaps due to vendor concerns of pump impeller corrosion issues if the pump is allowed to sit idle greater than that period. The operating procedure was revised so that during future CVP swaps, the manual suction isolation valve for the CVP being swapped from will be closed prior to securing the operating CVP, so that there will be not be a potential for a similar event occurring should as suction isolation valve not auto close.

From RII NITA on 4/29/2022:

At -4:00 am on April 29, 2022, the licensee was swapping main condenser vacuum pumps as part of the nonnal monthly plant secondary equipment rotation swap. The 'A' condenser vacuum pump (CVP) was started and verified to be operating properly, and the 'B' CVP was being secured. When secured, the 'B' CVP suction valve failed to go shut as designed, allowing an open pathway from the condenser to atmosphere. While an operator was stationed locally to close the upstream suction isolation valve for the 'B' CVP, over the next several minutes, condenser vacuum degraded from 2.0 "HG (normal) to 8.5"HG prior to the isolation valve being shut. At 4:05, in anticipation ofreaching the turbine trip condenser vacuum Page 25 of 34

setpoint of 8.86"HG due to degrading condenser vacuum conditions, the Shift Manager directed a manual reactor trip to be inserted.

The operators entered their emergency operating procedures and successfully stabilized the plant in Mode 3 without any complications. All plant safety equipment operated as expected during and fo llowing the reactor trip. Both motor driven and turbine driven auxiliary feedwater initially started automatically (not unexpected) due to reaching their steam generator water level actuation setpoints, but were subsequently secured as part of the normal plant recovery actions. Shortly after the reactor trip, the local operator completed isolation of the 'B' CVP suction isolation valve and condenser vacuum was restored using the 'A' CVP. There have been no additional problems with maintaining adequate condenser vacuum. The licensee is developing troubleshooting plans to investigate the cause of the 'B' CVP suction valve failure to close.

==

Description:==

MANUAL REACTOR TRIP AND AUXILIARY FEEDWATER SYSTEM ACTUATION The following information was provided by the licensee via email:

"At 0405 Eastern Daylight Time (EDT), with Unit 1 in Mode 1 at 100 percent power, the reactor was manually tripped due to degrading condenser vacuum. The trip was not complex, with all systems responding normally post-trip. The Auxiliary Feedwater System started automatically as expected.

"Operations responded and stabilized the plant. Decay heat is being removed by the Main Steam System to the main condenser using the turbine bypass valves.

"Due to the Reactor Protection System actuation while critical, this event is being reported as a four-hour, non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B). This event is also being reported per 10 CFR 50.72(b)(3)(iv)(A) as an event that resulted in a valid actuation of the Auxiliary Feedwater System.

"There was no impact on the health and safety of the public or plant personnel. The NRC Resident Inspector bas been notified.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

Page 26 of 34

No Tech Spec limits were exceeded. Offsite power is available. The suspected cause for the loss of condenser vacuum is when perfonning the scheduled monthly swap of condenser vacuum pumps, a suction valve failed to shut.

ML Number:

Sent to:

Scram Trending* - Rebecca.Sigmon@nrc.gov PUMP & VALVE - Thomas.Scarbrough@nrc.gov

5) EN (55871) - FitzPatrick - HIGH PRESSURE COOLANT INJECTION (HPCI) INOPERABLE Open in RPS-Oversight Screening Level: Level 1 Notes:

4/29/22 - HPCI gland seal condenser high level relay failed resulting in excess condensate build up in the gland seal condenser and making its way into the HPCI turbine. HPCI declared inoperable, but available at 12:51 on 4/29/22.

==

Description:==

HIGH PRESSURE COOLANT INJECTION (HPCI) INOPERABLE The following information was provided by the licensee via email:

"At 1251 EDT on April 29, 2022, while h*oubleshooting the failure of the High Pressure Coolant Injection (HPCI) Exhaust Drain Pot High Level Alarm to clear, it was discovered that the High Pressure Coolant Injection exhaust line condensate drain system was not functioning as designed to support removal of condensate from the turbine exhaust. This resulted in some water accumulation in the turbine casing. Subsequently, the High Pressure Coolant Injection System was declared inoperable. As a result, this condition is being reported under 10 CFR 50.72(b)(3)(v)(D) as a condition that could have prevented fulfillment of the safety function at the time of discovery. "

ML Number:

Page 27 of 34

Sent to:

ECCS - Christopher.Jackson@nrc.gov I&C - DXK4@mc.gov

6) Regional Call/NITA - Wolf Creek 1, Cooper - Severe Weather Impacts Due to High Winds/Tornados Open in RPS-Oversight Screening Level: Level 1 Notes:

==

Description:==

On 4/30/2022, severe weather moved through Kansas and Nebraska. Wolf Creek commenced a downpower to approximately 58% due to the loss of the 345 KV Rose Hill line (one of 3 offsite power lines to plant). Their off normal procedure requires them to lower unit load to less than 745 MW electric as directed by load dispatcher. The loss of the line was due to tornado activity in Andover, KS (approximately 100 mi from site) which caused major damage to the line. The Rose Hill line was restored on 5/ 1/2022.

At Cooper, the storms knocked down a power line from of the the 5 offsite power lines. One of the site output breakers tripped open when the line was lost. Both the output breaker and the offsite power line have been restored.

ML Number:

Sent to:

ELECTRICAL PWR - Jorge.Cintron@nrc.gov Page 28 of 34

From: NRR PRO IOEB Resource@nrc goy To: Winslow. Julie

Subject:

IOEB Clearinghouse Screening Summary for Tuesday, May 3, 2022 Date: Tuesday, May 3, 2022 1:44: 17 PM Total Issues: 3 NOTE: THIS

SUMMARY

IS FOR OFFICIAL USE ONLY

• • MAY CONTAIN SENSITIVE/PROPRIETARY OR NRC INTERNAL USE ONLY INFORMATION**

DO NOT FORWARD ANY PORTIONS OUTSIDE OF NRC WITHOUT FIRST OBTAINING PERMISSION FROM ORIGINATOR (Note - The infonnation in this part of the Summary is often preliminary in nature and is provided to help IOEB staff communicate and track noteworthy items being followed up by either the Regions or HQ staff.]

1) EN (55866)- Sequoyah 1, Sequoyah 2 - Retraction -

NOTICE OF UNUSUAL EVENT Open in RPS-Oversight Screening Level: Level 1 Notes:

From RII NITA on 4/29/2022:

At 23:55 EST, April 28, 2022, Sequoyah declared a Notification of Unusual Event (NOUE) due to a seismic event as indicated by seismic annunciators in the Unit 1 main control room and ground motion sensed by security personnel (emergency action leve l (EAL) HU2, Seismic event greater than Operating Basis Earthquake (OBE) levels). At 23:56, both units entered AOP-N.05, Earthquake, which contains steps to perfonn damage assessments and check the validity of seismic indications. Troubleshooting activities and engineering review of the response spectra analysis revealed that channel 2 on the XT-52-75B accelerometer was failed; channel 2 was the only channel out of three that indicated movement on the seismic report. Civil engineering reported that the graphs from the seismic report were not indicative of an actual earthquake. The licensee terminated the NOUE at 04:06 based on their conclusion that the event was caused by instrumentation failure and not an actual event. The licensee conducted a fatigue assessment of the individual who reported feeling ground motion (no impairment noted).

==

Description:==

Date Originally Screened: 5/2/2022 EN Revision Imported Date: 5/3/2022 EN Revision Text: NOTICE OF UNUSUAL EVENT Page 29 of 34

The following is a summary of information provided by the licensee via telephone:

On 04/28/22, at 2355 EDT, with both Sequoyah Unit 1 and 2 in Mode-1 , 100 percent, a Notice of Unusual Event was declared due to receiving two seismic alarms and security feeling ground movement. Additionally, security in a tower heard an explosion. Both units remain in Mode-1, 100 percent and they are investigating the validity of the seismic alarms before proceeding with the Abn01mal Operating Procedure required shutdown.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRC Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Notified DHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), DHS NRCC THD Desk(email), and DHS Nuclear SSA (email).

• • • UPDATE ON 04/29/2022 AT 0410 EDT FROM BRIAN KLEIN TO OSSY FONT***

The following is a summary of information provided by the licensee via telephone:

On 4/29/22, at 0406 EDT, Sequoyah Unit 1 and Unit 2 terminated the Notice of Unusual Event. The Civil Engineers determined that the alarms were due to a failed seismic indicator channel. Through interviews, only one security officer felt ground movement for a couple of seconds and heard a faint rumbling sound.

The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:

The licensee will notify the NRC Resident Inspector. The state of Tennessee and the Tennessee Valley Authority were notified.

Page 30 of 34

Notified R2DO (Miller), NRR EO (Miller), and IR MOC (Gott) via email.

Additionally, notified DHS SWO, FEMA Operations Center, CISA Central, FEMA NWC (email), DHS NRCC THD Desk(email), and DHS Nuclear SSA (email).

• **RETRACTION ON 05/02/2022 AT 2118 EDT FROM SCOTT SEAL TO LLOYD DESOTELL * *

• The following information was provided by the licensee via email:

"SQN [Sequoyah Nuclear Plant] is retracting the previous NOUE [Notice of Unusual Event]

declaration made on 4/28/22 at 2355 [EDT] based on Emergency Action Level HU2 for a seismic event greater than Operating Basis Earthquake levels. Following the declaration of the NOUE, the station reviewed all available indications and determined that a seismic event had not occurred. The instmmentation failure was documented under Event Notification #55867."

Notified R2DO (Miller), and IR MOC (Gott), NRR EO (Miller) via email.

ML Number:

Sent to:

OTHER- Kevin.Quinlan@nrc.gov, David.Heeszel@nrc.gov I&C- DXK4@nrc.gov EP - Jonathan.Fiske@nrc.gov

2) Regional Call/NITA - Clinton - Non-Conservative Modeling used in Cycle Thermal Limits Open io RPS-Oversight Screening Level: Level 1 Notes:

==

Description:==

Page 31 of 34

The licensee identified a non-conservativism in their transient analysis for the current cycle when following up on an inquiry from another utility. Specifically, the vendor (GNF) assumes in the transient analysis that the Level 8 turbine trip and Level 8 scram occur simultaneously.

The licensee identified that these trips are handled by two different sets of instrumentation with the same nominal trip setpoint and that the different sets of instrumentation may drift from the setpoint separately. The preliminary review of the worst case scenario for the instrumentation drift could be up to a 2.5 inch difference on when the trip is sensed. Actions are being developed and the vendor indicated a 0.03 operating limit maximum critical power ratio (OLMCPR) penalty would be conservative.

ML Number:

Sent to:

FUELS - Paul.Clifford@nrc.gov QANENDOR - Aaron.Armstrong@nrc.gov, Dong.Park@nrc.gov

3) EN (55814) - - EN Revision Imported Date: 5/3/2022 EN Revision Text: AGREEMENT STATE REPORT - LOST GD-153 SOURCE Open in RPS-Oversight Screening Level: Level 1 Notes:

EN not screened in Clearinghouse for INES level.

==

Description:==

EN Revision Impo1ied Date: 5/3/2022 EN Revision Text AGREEMENT STATE REPORT- LOST GD-153 SOURCE The following was received from the Washington State Department of Health, Office of Radiation Protection, via email:

"The Washington Agreement State program was notified on 3/31/2022, about a lost source.

Kaiser Permanente Bellevue lost a 10 mCi Gd-153 source. The source was in its leaded container in a shipping box and had not been processed in yet to the facility when housekeeping picked it up and threw it away. It then went to their own [trash] compactor and Page 32 of 34

tmfortunately was picked up by the garbage company. This event was only discovered a few hours ago.

"Washington State arrived onsite at Kaiser Bellevue at 1300 PDT and spoke with the Director oflmaging. Surveys of the garbage compactor [indicate that] the source is likely intact, as no contamination was found. The source is still lost, but is likely in the company garbage or landfill."

WA incident no.: WA-022-006

• **UPDATE ON 05/02/2022 AT 1526 EDT FROM TRISTAN HAY TO LLOYD DESOTELL * *

• The following update was received from the state of Washington via email:

"Based on their [licensee] corrective actions we [the state of Washington] have closed the incident. The lost source will most likely not be findable due to it making it into the landfill already and still being in its shielded container. "

Notified R4DO (Warnick) and ILTAB, NMSS Events Notification and CNSC via email.

THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL Sources that are "Less than IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a ve1y small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as moisture density gauges or thickness gauges that are Catego1y 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to http://www-pub.iaea.org/MTCD/publications/PDF/Pub 1227_web.pd[

ML Number:

Page 33 of 34

Sent to:

NMSS - Gretchen.Rivera-Capella@nrc.gov, Jennifer.Fisher@nrc.gov Page 34 of 34