ML24176A113

American Society of Mechanical Engineers,Section XI, Fourth 10 Year Inspection Interval, Inservice Inspection, System Pressure Test, Containment Inspection, and Repair and Replacement Programs, Owner’S Activity Report Cycle 21 Oper

ML24176A113
Person / Time
Site:	Browns Ferry
Issue date:	06/23/2024
From:	Sivaraman M Tennessee Valley Authority
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
Download: ML24176A113 (1)

Text

VALLEY TENNESSEE 1\\14 AUTHORITY

Post Office Box 2000, Decatur, Alabama 35609-2000

June 23, 2024 10 CFR 50.55a

ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001

Browns Ferry Nuclear Plant, Unit 3 Renewed Facility Operating License No. DPR-68 NRC Docket No. 50-296

Subject:

American Society of Mechanical Engineers,Section XI, Fourth 10 Year Inspection Interval, Inservice Inspection, System Pressure Test, Containment Inspection, and Repair and Replacement Programs, Owners Activity Report for Browns Ferry Nuclear Plant, Unit 3, Cycle 21 Operation

The Tennessee Valley Authority is submitting the Browns Ferry Nuclear Plant (BFN), American Society of Mechanical Engineers (ASME),Section XI, Owners Activity Report for BFN, Unit 3, Cycle 21 Operation. The report is contained in the enclosure to this letter and is in accordance with the requirements of ASME Code Case N-532-5, Repair/Replacement Documentation Requirements and Inservice Summary Report Preparation and Submission,Section XI, Division 1.

The report is an overview of the inservice examination results that were performed on components within the ASME Section XI boundary, up to and including the BFN, Unit 3, Cycle 21 refueling outage, during the third inspection period of the Fourth 10 Year Inspection Interval. The applicable provisions of the ASME Code Case N-532-5 require that this report be submitted within 90 calendar days of the completion of each refueling outage. The BFN, Unit 3, Cycle 21 refueling outage ended on March 24, 2024. Accordingly, this submittal is due by June 22, 2024.

U.S. Nuclear Regulatory Commission Page 2 June 23, 2024

There are no new regulatory commitments contained in this letter. Should you have any questions concerning this submittal, please contact David Renn, Site Licensing Manager, at (256) 729-2636.

Respectfully,

Manu Sivaraman Site Vice President

Enclosure:

American Society of Mechanical Engineers,Section XI, Fourth 10 Year Inspection Interval, Inservice Inspection, System Pressure Test, Containment Inspection, and Repair and Replacement Programs, Owners Activity Report for Browns Ferry Nuclear Plant, Unit 3, Cycle 21 Operation

cc (Enclosure): NRC Regional Administrator - Region II NRC Senior Resident Inspector - Browns Ferry Nuclear Plant NRC Project Manager - Browns Ferry Nuclear Plant Enclosure

Tennessee Valley Authority

Browns Ferry Nuclear Plant Unit 3

American Society of Mechanical Engineers,Section XI, Fourth 10 Year Inspection Interval, Inservice Inspection, System Pressure Test, Containment Inspection, and Repair and Replacement Programs, Owners Activity Report for Browns Ferry Nuclear Plant, Unit 3, Cycle 21 Operation

See Enclosed

FORM OAR-1 OWNER'S ACTIVITY REPORT

Report Number _,B""F'--'N'--'----'U"--'3"-'R--"2=-1.,__ ___________________________________ _

Plant Browns Ferry Nuclear Plant P 0. Box 2000 Decatur . AL 35609

Unit No . --~3~- date March 1 1977 Refueling Outage no . Refueling Outage 21

{if applicable) Commercial service

Current Inspe c tion Interval FO L![(h Ten Y ear lnspectio~n~ ln=t~e~rv~a~I __________ _______________ _

(1st, 2nd, 3rd, other)

Current Inspection Period ~T~h=ir~d~P_e=r~io~d~---------------------------------

(1st. 2nd. 3rd)

2007 Edition , 2008 Addenda ( ISi)

Edition and Addenda of Section X I applicable to the inspection plans ~2=0-'-1=3_,E=-d=i=ti=o~n__,_(=C~IS"'-'-'1)----------------- ~

0 -T PP -E NG -376. Re vision 0006, 02/07/2024 0-Tl-364 , Revision 0026, 11 /28/2023 Date and Revision of inspection plan 0-TPP-ENG-467 Revision 0002 02/05/2024

Edition and Addenda of Section X I applicable to repairs and replacemen ts, if different than the inspection plan ~N~/A~--

Code Cases used for inspection and evaluation N-508 -4 N-532 -- 5 N -6 13-2 N-648- 1 N-702 and N- 7 16-1 N-747 N-864.

(if applicable , including cases modified by Case N-532 and later revisions)

CERTIFICATE OF CONFORMANCE

I certify tl1at (a) the statempn tq m a de in this report are corre ct; (b) the exam inations and tests meet the In spection Plan as required by the ASME' Code , Section XI; and (c) the repai,/replacement act ivities and evaluations supporting the comp letion of --~U~ 3~R~2~1 __ _

conform to 11,e requireme *' -,ec tion XI. (refueling outage number)

Signed ______________________ Date _______________ _

Owner or Owner s Designee , Title

CERTIFICATE OF INSERVICE INSPECTION

I, the undersigned, holding a valid commission issued by the Na tiona l Board of Boiler and Pressure Vessel Inspectors and employed by The Hartford Steam Boiler Inspection and In surance Company of Hartford Connecticu t have inspected the items described in this Owner's Activity Report and state tha t, to the best of my knowledge and be lief, the Owner has performed all activities represented by this report in accordance w ith the requirements of Section XI.

By signing this certificate neither the In spector n or his emp loyer makes any war ranty, expressed or im plied , concerning the repair/replacement activities and evaluation described in this report. Furthermore, n e ither the Inspector nor his employer shall be liable in any manner for any persona l injury or property damage *r lo s of an r connected with this In spection.

'w; ~ /'1*1"11

--;--f,-'-"---,.,-:-':-::&c~+/---:._,,...,.--=--+------ --'--""'Na'-ti-on-al~B.,_oa~,d=-N-u-'-m-be-r a-n~d ~En-do-rs_e_m-en-, --'-'--'---J/'---Comm issions N ;3 i '19 '7 1 -r , IV R..

Date __ l;)'--lif----+,-"=--------/,/ lo/ 1 vt FORM OAR-1 OWNER'S ACTIVITY REPORT

TABLES Report Number BFN U3R21 ------ - ----- -------------- --- - -

PI ant Browns Ferry Unit No . 3 Commercial service date 03/01/1977 Refueling outage no . 21 - ---

Current inspection interval 4th Current inspection period 3rd ----- ----- --

TABLE 1 ITEMS WITH FLAWS OR RELEVANT CONDITIONS THAT REQUIRE EVALUATIONS FOR CONTINUED SERVICE Exam ination Category and Item Number Item Description Evaluation Description CR 1911989, NOi U3R21-001

During VT-3 examination of Mechanical Snubber Support, 3-47B400-75 , examiners identified the pin was displaced, not fully engaged with the suppo rt bracket, resulting in examination failure.

Civil Engineering evaluated the condition and F-A / F1.10D Main Steam System Snubber, concluded that the snubber in the "as found "

3-4 7B40 0- 75 condition would still be able to perform its intended design function and sustain the imposed design seismic loads. The design loads would have been transferred from the main steam piping to the EL 584 ' floor steel features. The snubber pin was reinstalled and a new cotter pin was installed topside of the support bracket. The support was then re examined with no recordable indication.

CR 1914074, WO 124338851 , NOi U3R21-003

During Owner Elected VT-3 examination of 3-47B455-628 the variable spring support was observed at an as found setting of 1650 lbs. The High Pressure Coolant Injection affected support nominal range setting is 1663 -

F-A / F1 .20C System Support , 3-47B455 -628 1738 lbs. The as found setting was roughly 1 %

outside of the acceptable nominal range, constituting a relevant condition as defined in IWF-3410(a)(4) , "Improper hot or cold settings of spring supports" . The spring can was reset to 1700 lbs.

and an a s left examination was performed with no relevant indications identified.

FORM OAR-1 OWNER'S ACTIVITY REPORT

TABLES Report Number BFN U3R21 -------------------------------

PI ant Browns Ferry Unit No . 3 Commercial service date 03/01/1977 Refueling outage no . 21 ----

Current inspection interval 4th ----- Current inspection period 3rd -------

TABLE 2 AB STRACT OF REPAIR/REPLACEMENT ACTIVITIES REQUIRED FO R CONTINUED SERVICE Code Item Description Description of Work Date Repair/Replacement Class Completed Plan Number During a pre-shutdown walk down a defect was revealed when a 1/2" drain pipe sheared at the heat affected zone at the Tee-to-Pipe interface due to cyclic fatigue cracking . (The valve at the end of the pipe was not supported and created a catalever at the pipe-to-tee joint.)

The defect was removed and 21 ,

Replace reducing Pipe Engineering Change (BFN Tee upstream of valve 010 (AWA-TVA-2024-04 38)) t~

2 BFN-3-VTV-074-0683A was performed to replace a c- o- 03/25/2024 124312449 with a 90-degree elbow degree elbow joint removing the and reducing insert catalever design issue with the drain valve.

The cause of the unacceptab ility is being documented in the BFN corrective action program CR 1911200 with an engineering evaluation shown in the Prompt Determination of Operability (PDQ) 1911200. An ECP was created to address the issue to prevent reoccurance .

FORM OAR-1 OWNER'S ACTIVITY REPORT

TABLES Report Number BFN U3R21 --------- - ---------- - ------

PI ant Browns Ferry Unit No. 3 Commercial service date 03/01/1977 Refueling outage no . 21 ----

Current inspection interval 4th ---- Current inspection period 3rd ------

REPORTING REQUIRED BY 10 CFR 50.55a(b)(2)(ix)(A)

ASME Section XI, Subsection IWE Steel Containment Vessel Inspection program

10 CFR 50.55a(b )(2)(ix)(A) requires reporting of the degradation assessment for inaccessible areas when conditions are identified in accessible areas during the perform a nce of the ASME Section XI, Subsection IWE Steel Containment Vessel (SCV)

Inspection Program that could indicate the presence of or result in degradation to such inaccessible areas.

During BFN U3R21, isolat ed locations of the Moisture Seal Barrier (MSB) of the SCV was identified to have disbonding conditions requiring excavations and examination of in acc e ssi le areas beneath the barrier. The inaccessible areas of the SCV Le neath the MSB we rP-. determined to be acceptable by General Visual examinat ion . Th e P. Xam ination irlGntifa:. d

• 1:J evidence of complete separation from the drywell liner that wou; ~1 ailow moistu 1 *~: to enter the area below the seal. Conditions were corrected by clea n ing and replacing damaged areas of the MSB with no Repair/ Replacement Activity required.