ML18024A709

LER 79-003/03L-0 on 790202:linear Heat Generation Rate Out of Tech Spec Limits.Caused by Operation Close to Limiting Values & Increase in Reactivity Due to Gadolina Burnup. Greater Margin to Limiting Value Will Be Maintained

ML18024A709
Person / Time
Site:	Browns Ferry
Issue date:	03/01/1979
From:	TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML18024A708	List: ML18024A707 ML18024A709
References
LER-79-003-03L, LER-79-3-3L, NUDOCS 7903070315
Download: ML18024A709 (2)

Text

NRC FORINI 366 U. UCLEAR REGULATORY COMMISSION I7:77 I LICENSEE EVENT REPORT CONTROL BLOCK: IPLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) 6 7 8 9 A L B LICENSEE CODE R F 3 Q2 14 15 0 0 0 0 0 LICENSE NUMBER 0 0 0 0 25 Q3 26 4 1 1 LICENSE TYPE 1 1 30 Qe~ 57 CAT 58 Qe CON'T

~O ~L LQB 0 5 0 0 2 9 6 7 0 2 0 2 7 9 B 0 3 0 1 7 9 QQB 7 8 60 61 DOCKET NUMBER 68 69 EVENT DATE 74 75 REPORT DATE 80 EVENT OESCRIPTION ANO PROBABLE CONSEQUENCES QIO

~oz During normal dail limits checks b the nuclear en ineer it was observed that the

~o 3 core maximum LHGR was out of limits per T AS. 3.5.J/3.5.L. No hazard existed to the

~o 4 plant or public health. No previous occurrences on unit 3'owever LER I

~os BFRO-50-260 770 unit 2 on Januar 19 1977.

~OB

~07

~OB 80 7 8 9 SYSTEM CAUSE CAUSE COMP. VALVE CODE CODE SUBCOOE COMPONENT CODE SVBCODE SUBCODE 7 8 z

10 Qll UAQle 11 UO3 12 13 18 8 UO>>

19 Uz 20 0'

REVISION SEOVENTIAL OCCURRENCE REPORT 6 "'""'U~ U LER(AO EVENT YEAR REPORT NO. CODE TYPE NO.

21 22 23 ELLE 24 28 U>

27 LLU 28 29 U"

30 LJ 31 Uo 32 ACTION FUTURE EFFECT SHUTDOWN ATTACHMEIeT NPROA PAIME COMP. COMPONENT TAKEN ACTION 33 QIB ~QIB 34 ON PLANT

~020 35 CAUSE OESCRIPTION AND CORRECTIVE ACTIONS 027 METHOD LlZ02 36 37 0 0 HOURS Q22 1 2 40 SUBMITTED

~N 41 023 FORM SUB.

~N02 42

~

SUPPLIER 43 Qzs 44 MANUFACTURER 47 026 o The unit performance with re ard to LHGR was found to be out of imi s Flow was dro e and rod ad ustments issued. Condition occurred values and increase in reactivity due to gadolina burnup. During future o eration a 3

greater margin to the limiting valve wi1 1 be maintained 7

~is 8 9 F AC I LITY STATUS E Qe ~O330

% POWER 9 9 OTHER STATUS NA 0 METHOD OF 0 I S COY E R Y

~A Q31 DISCOVERY DESCRIPTION Q32 Periddic monitoring of core performance 1 8 9 10 12 13 44 45 46 80 ACTIVITY CONTENT 6

RELEASED OF RELEASE

~Z ~Z NA AMOUNT OF ACTIVITY036 NA I.OCATION OF AELEASE Q Q33 034 7 8 9 10 44 45 80 PERSONNEL EXPOSURES NVMBEA TYPE DESCRIPTION Q39

~00 0 Qel Z Q33 NA 1 8 9 11 12 13 80 PERSONNEL INJURIES NUMBER OESCRIPTIONQi

~OO O Qee N4 7 8 9 11 12 LOSS OF OR DAMAGE To FACILITY TYPE DESCRIPTION Q43 LiJ042 NA 7 8 9 10 80 P V 8 I. I C I T Y NRC USF ONLY ISSUED OESCAIPTION Q46 o @@044 NA ee 7 8 9 10 68 69 80 "

I 0

NAME OF PREPARER PHONE: 0 7903070 3(S

Form BF-17 BF 15.2 S/09/78 LER SUPPLEi>IENTAL INFORMATION BFRO 296 / 793 Technical S pecification Involved 3. S. J/3. 5. L Reported Under Technical Specification 6. 7. 2.b. 2 Date of Occurrence 2-2-79 Time of Occurrence 0700 Unit 3 Identification and Descri tion of Occurrence:

normal that the core daily limits checks by the nuclear engineer maximum LHGR was out of limits.

'uring it was determined Conditions Prior to Occurrence:

Steady state 99K power.

Action specified in the Technical Specification Surveillance Requirements met due to inoperable e ui ment. Describe.

A arent Cause of Occurrence:

Running unit to close to core limits.

Anal sis of Occurrence:

More consideration to gadolina burnup should have been exercised which would have placed unit operation further from core limits.

Corrective Action:

Future core maneuvers will maintain sufficient margin to core limits to compensate for gadolina effects.

Failure Data:

Tennessee Valley Authority - Browns Ferry Nuclear Plant