ML20084T925

LER BFRO-50-259/7614:on 760823,seismic Setpoints for SMA Accelerometers & Alarm Triggers Found Incorrect.Caused by Inadvertently Reversed Seismic Setpoints in Surveillance Instructions.Instructions Corrected

ML20084T925
Person / Time
Site:	Browns Ferry
Issue date:	09/21/1976
From:	Fox H TENNESSEE VALLEY AUTHORITY
To:	Moseley N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
LER-BFRO-50-259-761, NUDOCS 8306240277
Download: ML20084T925 (3)

Text

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CONTAOL BLOCK:l l l l l l l 1 6 (PLIASE PRINT ALL REQUIRED INFORMATION]

NA g LCENSE NUMBER PE TYPE Q l Al Ll Bl Rl Fl 1l l0 l0 l-l 0 l 0l 0] 0l 0l-l0 l0 l l4l1 l1 l1l1l 7 89 l0 I 3_j 14 15 25 26 30 31 32 CATEGORY T E DOCKET NUMSER EVENT DATE hCON'T 7 8 57

[ l58l [59LJ 60lL l l0l5l0l-l0l2lSI9l68 61 l690l 8l 2l 3l 7l 6l l l REPORT DATE l l l l l 74 75 80 EVENT DESCAIPTION g l Units 1 and 2 in REFUEL mode; unit 3 in STARTUP mode at 50 psig. The seismic setnointsl 7 89 CO t

g l for: (1) SMA accelerometers were found at 0.lg and not 0.01g as recuired: and (2) Alarm l 7 69 80 g j triggers were found at 0.Olg and not 0.lg as required. Capability of SMA accelero- l 7 89 SE l graphs to monitor possible operatine basis earthcuakes (>0.1c) van preserved. l 7 89

,gl BFRO-50-259/7614 80 7 80 _l PPatE 60 E COOE COMPONENT CODE R MANUF VOLAW BE ] Il Fj [D_] lZ lZ lZ lZl Zl Zl [J.J lZl919l9l47 (_y_j 7 89 10 11 12 _ 17

• 43 44 48 CAUSE DESCAIPTION gg l Seismic setpoints inadvertently reversed in surveillance instructions for 3 SMA 7 89 J 80

@ l accelerometers and 3 alarm triggers. Equipment: kinemetrics SMA-2 (accelerometers) 7 89 l DE l and MS-3 (triggers). Surveillance instructions corrected. l 7 89 C' " 80

's'YATUS  % POWER OTHER STATUS DISC VERY DISCOVERY DESCR@fCN 7 8 W

9 l 0l 0l 0l l 10 12 13 NA l 44 d45 l Review of technical specifications l 46 60 ES AMOUNT OF ACTnnTY 12 7 8 9

(_Zj OS j NAGE l NA l l LOCATON OF RELEASE NA l 10 11 44 45 PERSONNEL EXPOSURES 80 NoveE R tvPe cESCwf0N gg l0 l 0 l 0l _

[Zj l NA 7 89 11 12_ 13 {

EO PERSONNEL INJUATES NUM BE R CESCMTON 3 l0l0l0l11 12l 7 89 NA l

80 OFFSITE CONSEGUENCES HI m 1 7 89 '

LOSS OA OAMAGE TO FACillTY 80 TYPC

@ y lDE3CRIPTON NA 7 89 10 l t a lC Tv 8306240277 760921 80 DRADOCK05000g 7 89 80 ADO!TIONAL FACTOAS 1 e l Investigation shows that instrument maintenance instruction (IMI) 3004, " Seismic }'

7 89 60 g l Instrumentation," issued on 6/4/73, contained the required setpoints. These values 7 89 j (Continued next, sheet) 80 NAME:

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LICENSE EVENT REPORT (Continued)

I BFRO-50-259/7614 ADDITIONAL FACTORS (Continued) 20 were inadvertently transposed when the initial surveillance instructions 21 (SI 4.2.J-1 and -2) were prepared on 5/11/76, in anticipation of expected 22 plant technical specifications.

23 These reversed setpoints were confirmed on 8/23/76 when the units 1 and 2 24 !technical specifications were fully reviewed.

With the setpoints reversed, 25 the SMA was capable of monitoring and documenting on a seismograph tape any 26 tremor 50% below the design basis earthquake (DBE) of 0.2g, which 27 corresponds to the operating basis earthquake (OBE). If an earthquake had 28 occurred while the setpoints were reversed, the only unavailable post-29 earthquake information would involve tremors below the OBE (>0.01 but <0.lg).

30 Consequently, this deficiency did not prevent plant seismic instruments from 31 performing their intended function.

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[ C TENNESSEE VALLEY AUTHORITY a

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e CHATTANOOGA. TENNESSEE 37401 2p#2

/6 19 Septer.ber 21, 1976 ,

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, Mr. Norman C. Moseley, Director f4 N Jbt [sj ht.

U.S. Iluclear Reculator/ Com:ission - ~Gf Offico of Inspection and D1 force:aent .

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g,, RcJion II .

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., 230 reachtree Stecct,174., 8th Floor . assiseen v3 Atlanta, Georgia 3v303 g //

Dear 1/.r. Hoscley:

TI2HE3SEE VAI2Ef AUTIIORITY - ERO.'Ii3 FERRY HUCIS\R FIAITf UllIT 1 -

DOCKET NO. 50-259 - FACTr.T'n otEFATIITG LICE:0E DFR REPORTABIS OCCUd1EUCE RE:0RT B310@-25)/761)

The enclosed report la to provide details concerning the sciauic 2ctpointa for GMA accolcro;.cters and alana triggers that ucre not act J n accorutnce with technical require 2cnta. This report is sube.dtted in accordance with Bro;na Ferr/ ~ Technical Syccifications 3cctic11 6. ~d.s u c.eut occurred ca ru. onus b r,y I;ue lua c ' ila ni, unit 1.

Very trt0y yours, TEIEMSHS VALIrf AUTHORITY H. S. Fox 3

Director of Itwer IToduction k

Enclosure (3)

CC (Enclosuro):

Director (3)

, Cffico of Zhnaccaent Inforcation and Irogram Control i U.G. Ilucicar Regulatory Cocaission )

Vechington, D.C. 20555 1

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4 _Directar RO) i Offico of Inspection and Enforce. tent i

U.S. Ifuclear Regulatory Cocmission f Washington, D.C. 20555 l

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l 8811 -

l COPY SENT REGL- .

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An Eriual Opportunity fimployer

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