05000457/LER-1993-004
| ML20056D455 | |
| Person / Time | |
|---|---|
| Site: | Braidwood  |
| Issue date: | 08/11/1993 |
| From: | Kofron K, Jesus Sanchez COMMONWEALTH EDISON CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| BW-93-0228, BW-93-228, LER-93-004-08, LER-93-4-8, NUDOCS 9308160233 | |
| Download: ML20056D455 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| 4572093004R00 - NRC Website | |
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" Braidwood Nuclear Power Station Route #1, Box B4 V' Braceville, Ittinois 60407
. Telephone 815/458-2801 3
August 11, 1993 Bii/ 93-022 8 U. S. Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555
Dear Sir:
The enclosed Licensee Event Report from Braidwood Generating Station is being transmitted to you with the rea,uirement of 10CFR50.72 (a) (2) (i) (B) , which requires a 30-day written report.
This report i s n u:ri; e r 93-004-00, Docket No. 50-457. l
/.b c K. L. K' . ron Station Manager Braidwood Nuclear Station ,
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-i Encl: Licensee Event Report No. 50-457/93-004-00 cc: NRC Region III Administrator :
NRC Resident Inspector INPO Record Center )
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i PDR ADOCK 05000457 S PDH g.
~NRC FORM 366 U.S. NUCLEAd REWLATORY COMMISSION APPROVED BY OMB NO. 3250-0104
'(5-92) EXPIRES 5/37/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH I CTI0N R '
LICENBEE EVENT REPORT (LER) Mago"l"Nu"C0((,[aowcguRDEN g hSf! TE D THE INFORMATION AND RECORDS MANAGEMENT BRANCH (MNBB 7714), U.S. NUCLEAR REGULATORY COMMIS$10N, (See reverse for required ruber of digits / characters for each block) WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.
FACILITY hAME (1) DOCKET NLMBER (2) PAGE (3)
Braidwood 2 05000457 1 OF 5 TITtE (4)
Core reactivity normalization surveillance not performed in required time frame due to personnet error EVE NT DATE (5) LER WUMBER (6) REPORT DATE (7) OTHER F ACitITIES INVOLVED (8)
MONTH DAY YEAR YEAR MONTH DAY YEAR 0 0 07 12 93 93 -- 004 -- 00 08 11 93 O O OPERATING THIS REPORT IS SURMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR 1: (Check one or more) (11)
C~ DOE (9) 20.402(b) 20.405(c) ' 50.73(a)(2)(iv) 73.71(b)
POWER '""
099 20.405(a)(1)(fi)
LEVEL (10) 50.36(c)(2) 50.73(a)(2)(vii) OTHER 20.405(a)(1)(iii) X 50.73(a)(2)(i) 50.73(a)(2)(viii)(A) (Specify in 20.405(a)(1)(iv) 50.73(a)(2)(ii) ac w 50.73(a)(2)(viii)(B) 20.405(a)(1)(v) 50.73(a)(2)(iii) 50.73(a)(2)(x) NRC Form 366A) llCENSEE CONTACT FOR THIS LER (12)
NAME TELEPHONE NUMBER (include Area Code)
J. Sanchez, Systems Engineering (815)458-2801 x2490 COMPLETE ONE LINE FOR EACH COMPOWENT FAltuRE DESCRIBED IN THIS REPORT (13)
CAUSE SYSTEM COMPONENT MANUFACTURER CAUSE SYSTEM COMPONENT MANUFACTURER No SLPPLEMENTAL REPORT EXPECTED (14) EXPECTED MONTH DAY YEAR TES SUBMISSION (If yes, complete EXPECTED SUBMIS$10N DATE). DATE (15)
ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)
F Technical Specification Surveillance Requirement 4.1.1.1.2 requires normal-ization of predicted reactivity values to actual core conditions prior to exceeding a fuel burnup of 60 Effective Full Power Days (EFPD) after each fuel loading. The surveillance that satisfies this requirement (BWVS 1.1.1.2-2) was not performed until approximately 62.67 EFPD after the third refueling outage on Unit 2. No impact on core monitoring occurred because no comparison of the overall core reactivity balance to predicted values (per BWVS 1.1.1.2-1) was performed or due in the period during which normalization was past due. The causes of this event were cognitive personnel error and programmatic deficiency. Methods to better track this type of surveillance, Technical Specification applicability, and surveil-lance frequency update methods will continue to be investigated. There
, have been previous occurrences in which Technical Specification surveil- ,
lances have not been performed within the specified frequency, although the l events were seen as unrelated to this event. l l
l 1
MCFed366 (5 92)
NRC FORM 366A U.S. NUCLEAR REGULATORY CONISSION APPROVED BY OMB NO. 3150-0104 (5-92) , -
EXPIRES 5/31/95 ,
ESilMATED BURDEN PER RESPONSE TO COMPLY WITH THl$ INFORMATION COLLECTION REQUEST: 50.0 HRS.
FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO LICENSEE EVENT REPORT (LER) THE INFORMATION AND RECORDS MANAGEMENT BRANCH TEXT CONTINUATION (MNss 7714), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.
FACILITY KAME (1) DOCKET NLMBER (2) LER NUMBER (61 PAGE (3)
Braidwood 2 YEAR SEQUENTIAL REVISION 05000457 93 --
004 -- 0 TEXT (If more space is reavired, use e&fitional copies of NRC Form 366A) (17)
A. PLANT CONDITIONS PRIOR TO EVENT:
1 Unit: Braidwood 2; Event Date: July 12, 1993; Event Time: 1045; Mode: 1 - Power Operation; Rx Power: 099%; i RCS [AB] Temperature / Pressure: NOT/NOP B. DESCRIPTION OF EVENT:
There was no equipment or systems inoperable at the beginning of the event that contributed to the severity of the event.
Technical Specification Surveillance Requirement 4.1.1.1.2 requires that the predicted reactivity values be adjusted (normalized) to correspond to the actual core conditions prior to exceeding a fuel burnup of 60 Effective Full Power Days (EFPD) after each fuel loading. When core burnup was checked to establish the time frame during whien the surveillance that satisfies this requirement could be scheduled, it was discovered that core burnup was in excess of the required 60 EFPD. The surveillance was immediately begun. Concurrently, the individual in Regulatory Assurance responsible for compliance with Technical Specifications was notified of the discrepancy. This individual then immediately informed the Operating Engineer responsible for Unit 2 operations. Technical Specification Action -
Requirements were immediately checked to ensure that all required actions ;
were taken. Following completion of the surveillance, the unit's burnup history was reviewed to determine the date and time at which the Surveillance Requirement was exceeded. This occurred at 1900 on July 9, i 1993 (a Friday).
C. CAUSE OF THE EVENT:
The primary cause of this event was cognitive personnel error, in that the i System Engineer responsible for tracking and scheduling this surveillance j (BWVS 1.1.1.2-2) did not correctly identify the need to complete the !
surveillance until after the required maximum fuel burnup for the present :
fuel reload had been exceeded. i Several contributing programmatic causes contributed to this error. At the ,
time of occurrence of this event, the responsibility for tracking and !
scheduling surveillances under the System Engineering's Nuclear Group control had recently been reassigned. The person assuming responsibility had not adequately reviewed the unit's status regarding BWVS 1.1.1.2-2. .
KRCFCIM'366(5-92)
MRC FORM 366A U.S. NUCLEAR REGULATORY COMISSION APPROVED BY OMB No. 3150-0104 (5-92) EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS.
LICENSEE EVENT REPORT (LER) [^1wr0 AN ECIDS MANAGE BYAN$
TEXT CONTINUATION (MNB8 7714), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.
FACILITY KAME (1) DOCKET WUMBER (2) LER NLMBER (6? PAGE (3)
Braidwood 2 YEAR SEQUENTIAL REVISION 05000457 93 0 3 OF 5
- 004 -
iEXT (If more space is recuired use additional copies of NRC f orm 366A) (17)
At the time of this event's occurrence, the person assuming responsibility was also responsible for tracking and trending the elevated iodine activity level in both Unit 1 and Unit 2. This represented a significant workload, leading to distraction from adequate tracking of the status of BwVS 1.1.1.2-2.
The required time for performance of surveillances whose surveillance frequency is specified in terms of fuel burnup is difficult to track with existing tracking mechanisms. This is also true for surveillances performed on an infrequent basis. The surveillance tracking mechanism currently in use, GSRV (a computerized data base), tracks surveillance requirements by date. The date calculated by GSRV for the normalization surveillance was based on an 18 month periodicity, since Braidwood operates on a nominal 18 month fuel cycle. No correction to the due date had been accomplished to reflect the actual beginning of cycle date. For this reason, GSRV identified a date in August for the required BwVS 1.1.1.2-2 completion time. Notification is provided for surveillances due within 3 weeks, therefore GSRV did not identify the requirement for performance of BwVS 1.1.1.2-2.
Additionally, no system currently exists to automatically track fuel burnup at Braidwood Station. The System Engineering Nuclear Group manually tracks Effective Full Power Hours, but this number is not also expressed in EFPD.
Since the conversion from EFPH to EFPD is not one readily made mentally, this is another factor that contributed to this event.
Do BAFETY ANALYSIS:
There were no safety consequences arising from this event. The reason for !
performing the normalization specified by Technical Specification Requirement 4.1.1.1.2 is not explained in the " Bases For Sections 3.0 and 4.0 Limiting Conditions For Operation and Surveillance Requirements" section of Technical Specifications. The reason for this normalization is to correct the predicted reactivity balance of the reactor core to the measured reactivity balance. This makes identification of an adverse trend of the measured reactivity balance with respect to the predicted reactivity balance easier. Comparison of the predicted to measured core rcactivity was not performed, nor was performance due, during the time frame in which the normalization was past due.
The desired fuel burnup at the time of normalization is near, but not in
- excess of, 60 EFPD. The characteristic response of the reactivity balance l st the beginning of core life is such that at zero burnup the difference between predicted and measured values is relatively large, but becomes less as burnup increases. This makes performance of the normalization at a very low burnup undesirable.
ERCFC[M'366(5-92)
NRC FORM 366A U.S. NUCLEAR RE(13LATORY COMISSION APPROVED BY OMB No. 3150-0106 (5-92) EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS.
LICENBEE EVENT REPORT (LER) $"g"^tr0RN$ AN ^ REC OS NAGEWN ERAN TEXT CONTINUATION (MNss m4), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE Of MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.
FACit1TY KAME (1) DOCKET NUMBER (2) LER NLMBER (63 PAGE (3)
Braidwood 2 ygAR SEQUENTIAL REVISION 05000457 93 4 of 5 004 -- 0 TEXT (If more sosee is reovired, use additionet confes of NRC Form 366A) (17)
The worst case situation for this event would be an occurrence in which a predicted to measured core reactivity balance comparison had been performed while the normalization was past due. There would have been no safety significance to this situation either, since an adverse trend could still have been identified.
E. CORRECTIVE ACTIONS:
The immediate corrective actions taken were to commence performance of the required surveillance. Concurrently the Regulatory Assurance person in charge of ensuring conformance to Technical Specifications and the Unit Operating Engineer were contacted to assure that required actions had been performed. ;
The System Engineering individual directly involved with this missed surveillance was put in charge of the investigation of the event to help determine the causes and corrective actions. Additionally, he gave a Lessons Learned presentation to the entire System Engineering Department on July 29, 1993, outlining the circumstances that caused the missed surveillance.
i An In-House Operating Experience Report was generated and distributed to j all departments within Braidwood Station that identified factors that have caused missed surveillances in the past. This report identified this event, and a later missed surveillance event, and emphasized the need to ensure that a proper focus is maintained on completing required ;
surveillances. l Braidwood's governing startup test procedure (BwVS 500-3) will be revised to require that surveillance due dates whose frequencies are specified in l terms of fuel burnup will be changed to conservatively reflect the actual date for the start of the fuel cycle. This action will be tracked to !
completion by Action Item 457-180-93-00401. l l
The surveillance procedure governing performance of the reactivity balance l (BWVS 1.1.1.2-1) will be revised to require the following action. If the reactivity balance normalization surveillance (BwVS 1.1.1.2-2) has not yet been performed for the current cycle, the reactivity balance normalization surveillance due date will be changed to reflect the actual fuel burnup at the time that BwVS 1.1.1.2-1 is performed. This action will be tracked to completion by Action Item 457-180-93-00402.
r I
. . s 4RC FORM 366A U.S. C% CLEAR REGULATIDT COMMISSIlO APPROVED BY OMB NO. 3950-0104 (5-92) EXPIRES 5/31/95 ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS.
FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO LICENSEE EVENT REPORT (LER) THE INFORMATION AND RECORDS MANAGEMENT BRANCH TEXT CONTINUATION (MNas m 4), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF
_ MANAGEMENT AND BUDGET, WASHINCTON, DC 20503. !
FACillTY NAME (1) DOCKET NUMBER (2) LER NLMBER (6? PAGE (3)
Braidwood 2 YEAR SEQUENTIAL REVISION 05000457 93 0 5 OF 5
-- 0 0 4 --
TEXT (if more space is recuired, uc.e e&fitionet ecoies of hRC Form 366A) (IT)
An investigation will be conducted to determine the most effective way of automatically tracking fuel burnup for each cycle, and using this information to identify required performance dates for surveillances whose frequencies are specified in terms of fuel burnup. The identified tracking mechanism will then be implemented. This action will be tracked to completion by Action Item 457-180-93-00403.
The applicability of the circumstances surrounding this event to other infrequently performed procedures will be investigated. If the situation is found to be applicable, appropriate actions to prevent similar events will be implemented. This will be tracked by Action Item 457-180-93-00404.
Other corrective actions taken were to investigate the corrective actions taken in response to previous missed surveillance occurrences. None of the corrective actions identified directly applied to this event, although two identified events involved due dates based on fuel burnup. These events occurred more than three years previous to this event, and are therefore not addressed further in this document.
F. PREVIOUS OCCURRENCES:
There have been previous occurrences in which Technical Specification surveillances have not been performed within the specified frequency.
Although in some cases the cause of these events is personnel error, the corrective actions taken for these occurrences are not applicable to this event.
G. COMPONENT FAILURE DATA:
l This event was not the result of component failure, nor did any components fail as a result of this event.
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