ML17311B072

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LER 95-004-00:on 950706,identified Four Occassions Between 950407 & 0630 When Conditional Surveillance in TS LCO 3.8.4.1 Action a Not Performed Due to Inattention to Detail. CR Copy of Temporary Procedure 40TP-9ZZ04 Corrected
ML17311B072
Person / Time
Site: Palo Verde Arizona Public Service icon.png
Issue date: 07/20/1995
From: Grabo B
ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:
Shared Package
ML17311B071 List:
References
LER-95-004-01, LER-95-4-1, NUDOCS 9508010014
Download: ML17311B072 (14)


Text

LICENSEE EVENT REPORT (LER)

AGILITYNAME (I) DOCKET NUMBER (2) PAGE (3)

Palo Verde Unit 2 ~ 0 5 0 0 0 5 2 9 1OFO 7 ITLE (4)

Technical S ecification Violation Due to Missed Surveillance Re uirement EVENT DATE 5 LER NUMBER 6 REPORl'ATE OTHER FACIUTIES INVOLVED 6 MONTH YEAR SEOVENTIaL REVI8IOII MONTH DAY YEAR NUMBERS N/A 0 7 0 6 MODE (6) 9 5 9 5 - 0 0 4 - 0 0 0 7 2 0 9 5 N/A Is REPoRT Is BUBMITTEDPvRsvANT To THE REovIREMENTs oF 10 cFR C (cnecx one or more or tne 20.402(b) 2(L<<5(c) 50.73(s)(2)(rr)

~) (1 1) 73.71(b)

POWER 20.45(s)(1)(i) 50.35(c)(1) 50.73(a)(2)(v) 73.71(c)

LEVEL(to) 1 Q Q 20.45(s)(1)(rr) 50.35(c)(2) 50.73(s)(2)(vb) OTHER (Specify in Abstract 20.405(s) (t)(iii) 50.73(a)(2)Oi 50.73(a)(2)(v5i)(A) beiovv snd In Text, NRC Form 20.45(a)(1)(iv) 50.73(a)(2)(4) 50.73(s)(2)(via7(B) 365A) 20.405(a)(1}(v) 50.73(s)(2)(rii) 50.73(a)(2)(r)

LICENSEE CONTACT FOR THIS LER 1 AME EPHONE NVMBER Burton A. Grabo, Section Leader, Nuclear Regulatory Affairs 6 0 2 3 9 3 - 6 4 9 2 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE OESCRIBEO IN THIS REPOR T 13 MANVFAC. REPORTABLE, MANUFAC- REPORTABLE TVRER TO NPROS TURER TO NPRDS SUPPLEMENTAL REPORT EXPECTED 14 EXPECTED MONTH DAY YEAR SUBMISQON YES (N yes, complete EXPECTED SV BMISQON DATE) X DATE (1 5)

TRACT (Limn tO 1400 SPaCee, Le., SPPrOXimateIY Triteen Sin6Ie SPaoe tPPanrrisen Snea) (1 5)

On July 6, 1995, at approximately 1200 MST, Palo Verde Unit 2 was in Mode 1 (POWER OPERATION), operating at approximately 100 percent power when Control Room personnel i.dentified four occasions between April 7, 1995 and June 30, 1995 when the conditional surveillance in TS Limiting Condition for Operation (LCO) 3.8.4.1 ACTION a had not been performed. TS LCO 3.8.4.1 ACTION a requires veri,fication at least once per 7 days that inoperable electrical containment penetration circuit breakers remain open. On April 7, 1995 and June 16, 1995, the reactor cavity sump pump circuit breaker had not been verified. On April 7, 1995 and June 9, 1995, the normal access air filtration unit space heater circuit breaker had not been verified. A TS violation occurred when Unit 2 did not comply with the TS LCO 3.8.4.1 ACTION a.

An independent investigation of this event is being conducted in accordance

'with the APS Corrective Action Program. A preliminary investigation has determined that the cause of the event is attributed to inattention to detai,l by the Control Room personnel performing the conditional surveillance. A human performance evaluation will be performed as part of the investigation.

As correcti,ve action, a night order was issued to alert Control Room personnel of the event and to stress the importance of proper configuration control and attention to detail. If necessary, coaching will be administered followi.ng the outcome of the human performance evaluation.

There have been no previous similar events reported pursuant to 10CFR50.73.

I71508010014 '7150720 PDR ADC)CK 0500052'7I 5 PDR

t LICENSEE EVENT REPORT (LER) TEXT CONTINUATION AQLITYNAME DOCKET NUMBER LER NUMBER PAGE TEAR SEQUENTIAL 'EIIISO NUMBER NUMBER Palo Verde Unit 2 0 5 0 0 0 5 2 9 9 5 - 0 0 4 - 0 0 0 2 of 0 7

1. REPORTING REQUIREMENT:

This LER 529/95-004-00 is being written to report a condition prohibited by the plant's Technical Specifications (TS) as specified in 10 CFR 50.73(a) (2) (i) (B) .

Specifically, at approximately 1200 MST on July 6, 1995, Palo Verde Unit 2 was in Mode 1 (POWER OPERATION), operating at approximately 100 percent power when Control Room personnel (utility, licensed) identified four occasions between April 7, 1995 and June 30, 1995 when the conditional surveillance in TS Limiting Condition for Operation (LCO) 3.8.4.1 ACTION a had not been performed. TS LCO 3.8.4.1 ACTION a requires verification at least once per 7 days that inoperable electrical containment (NH) penetration circuit breakers remain open. On April 7, 1995 and June 16, 1995, the reactor (AC) cavity sump pump circuit breaker had not been verified. On April 7, 1995 and June 9, 1995, the normal access air filtration unit space heater circuit breaker had not been verified. A TS violation occurred when Unit 2 did not comply with the TS LCO 3.8 4.1 ~

ACTION a.

2. EVENT DESCRIPTION:

Prior to the event, on March 29, 1995, APS Engineering personnel (utility, non-licensed) determined that redundant overcurrent protection was not provided on thirty-four (34) electrical containment penetration circuits in each of Palo Verde Units 1, 2, and 3. This event was reported in LER 528/529/530/95-004-00 dated April 27, 1995. Control Room personnel in each unit declared the 34 affected containment penetration conductor overcurrent protective devices inoperable and entered the 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> ACTION statement of TS LCO 3,8.4.1 to (1) restore the protective devices to OPERABLE status, or (2) deenergize the circuits by tripping the associated backup circuit'reaker or by racking out or removing the inoperable device.

At that time, Unit 1 was preparing to shut down on April 1, 1995 for its "fifth refueling outage. APS requested, and was granted, a notice of enforcement discretion to extend the allowed outage time for TS LCO 3.8.4,1 to April 4, 1995 in order to allow the performance of steam generator (AB) high temperature chemical cleaning prior to cooling down to Mode 5 (COLD SHUTDOWN). Unit 1 entered Mode 5 at approximately 1008 on April 3, 1995 and exited TS LCO 3.8.F 1. The 34 protective devices were returned to OPERABLE status prior to the Mode 4 (HOT SHUTDOWN) entry on May 18, 1995.

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION AQUlYNAME DOCKET NUMBER LER NUMBER PAGE

'fEAR SECWENTIAL Palo Verde Unit 2 0 5 0 0 0 5 2 9 9 5 - 0 0 4 0 0 0 3 Cf 0 7 In Units 2 and 3, required modifications had been completed on nine (9) of the 34 containment penetration circuits required to be energized for safe plant operation within the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed by TS LCO 3.8.4.1. On March 31, 1995, the remaining 25 circuits were deenergized and the affected systems or components were declared inoperable. An approved clearance document was generated to track tag placement and tag removal for the circuits and affected systems and components. A TS Component Condition Repozt (TSCCR) was generated to track the inoperable TS components. The TSCCR was to include a hardcopy list of inoperable circuit breakers and affected TS equipment.

On April 6, 1995, APS Engineering personnel determined that three (3) of the 25 circuits had adequate existing protection for the associated containment penetrations and removed the 3 circuits from the list of electrical penetrations with deficient ovezcurrent protection. On April 7, 1995, appropriate tags were removed from the equipment and the TSCCR and clearance was reconciled with the remaining 22 deficient cizcui.ts.

A temporary procedure (40TP-9ZZ04) was approved on April 6, 1995 to satisfy the conditional surveillance in TS LCO 3.8.4.1 ACTION a by verifying at least once per 7 days that the 22 affe'cted circuits remain deenezgized until appropriate plant modifications were performed to allow energizing the affected circuits. 40TP-9ZZ04 requires (Step 8.1.1) a check of the TSCCR to determine the status of the modifications to the electrical penetrations, (Step 8.1.2) a placement of "N/A" in the initial block for any penetrations which have the required modifications completed, and (Step 8.1.3) verification of the remaining ci,rcuits which do not have the required modifications completed. The first performance of 40TP-9ZZ04 was scheduled for April 7, 1995 and subsequent performances every 7 days thereafter.

At approximately 1000 MST on June 30, 1995, during a review of 40TP-9ZZ04 previously performed at approximately 0145 MST on June 30, 1995, Control Room personnel discovered that reactor cavity sump pump circuit breaker (NHN-M1014) had not been verified open and determined that the verification was required as indicated in the TSCCR. When the Control Room personnel retrieved the Control Room copy of 40TP-9ZZ04 to perform the verification for NHN-M1014, they discovered that the procedure copy contained handwritten N/A's in four initial blocks, including the block for NHN-M1014. The procedure copy was reviewed against the TSCCR and two blocks were found to be pre-N/A'd in which the required modifications to the electrical penetrations were not performed. One block corresponded to NHN-M1014 and the other to the normal access air filtration unit space heater circuit breaker (NHN-D15-06). Control Room personnel removed the N/A', verified NHN-M1014 was open prior to exceeding the 7 days allowed

Ij LICENSEE EVENT REPORT (LER) TEXT CONTINuATION DOCKET NUMBER LER NUMBER PAGE yEAR BEQUENTlAL RENSO NUMBER NUMBER Palo Verde Unit 2 0 5 0 0 0 5 2 9 9 5 - 0 0 4 - 0 0 04of07.

by TS LCO 3.8.4.1, and notified Control Room supervision of the procedural problem (i.e., pze-N/A'd initial blocks) .

An investigation was initiated, and included a review of the previous .

performances of 40TP-9ZZ04 in both Units 2 and 3 since April 7, 1995.

Several performances of 40TP-9ZZ04, in Uni.t 2 only, included blocks with N/As that were questionable. At approximately 1200 MST on July 6, 1995, as part of the investigation, Control Room personnel identified four occasions in Unit 2 between April 7, 1995 and June 30, 1995 when the condi.tional surveillance in TS LCO 3.8.4.1 ACTZON a had not been performed in that the initial blocks in 40TP-9ZZ04 were inappropriately N/A'd. A summary of the performances of 40TP-9ZZ04 for Unit 2 is provided below.

04/07/95* NHN-M1014 and NHN-D15-06 were inappropriately N/A'd.

04/14/95 All deficient circuit breakers were appropriately verified, 04/21/95 NHN-M1014, NHN-D15-06, and the steam generator wet layup pump motor space heater (NHN-D10-20) were inappropriately N/A'd by the reactor operator '(utility, licensed). However, .the auxiliary operator (utility, non-licensed) performing 40TP-9ZZ04 stated that he had checked all the circuits in the TSCCR.

04/28/95 All deficient circuit breakers were appropriately verified.

05/05/95 All deficient circuit breakers were appropriately verified.

05/12/95 All deficient circuit breakers were appropriately verified.

05/19/95 All deficient circuit breakers were appropriately verified.

05/26/95 All deficient circuit breakers were appropriately verified.

06/02/95 All deficient circuit breakers were appropriately verified.

This was the first appearance of the pre-N/A'd version of 40TP-9ZZ04. The blocks for NHN-M1014 and NHN-D15-06 were initialed as verified.

06/09/95* 40TP-9ZZ04 was pre-N/A'd. NHN-D15-06 remained inappropriately N/A'd. NHN-M1014 was initialed as verified.

06/16/95* This was not a pre'N/A'd version of 40TP-9ZZ04. However, NHN M1014 was inappropriately N/A'd.

06/23/95 All deficient circuit breakers were appropriately verified.

40TP-9ZZ04 was pre-N/A'd. However, the N/A's for NHN-M1014 and NHN-D15-06 were appropriately crossed out and the block initialed as verified.

06/30/95 All deficient circuit breakers were appropriately verified.

40TP-9ZZ04 was pre-N/A'd. The N/A for NHN-D15-06 was appropriately crossed out and the block initialed as verified.

NHN-M1014 was inappropriately N/A'd. However, the error was detected prior to the expiration of the 7 days.

  • Denotes the surveillances that were inappropriately performed.

t I

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION AQUTY NAME DOCKET NUMBER LER NUMBER PAGE YEAR SEQUENRAL REIASIO NUMBER NUMBER Palo Verde Unit 2 0 5 0 0 0 5 2 9 9 5 - 0 0 4 - 0 0 05of 0 7 TS LCO 3.8.4.1 ACTION a requizes verification at least once per 7 days that inoperable electrical containment penetration circuits breakers remain open. On April 7, 1995 and June 16, 1995, the reactor cavity sump pump circuit breaker had not been verified. On April 7, 1995 and June 9, 1995, the normal access aiz filtration unit space heater circuit breaker had not been verifi.ed. A TS violation occurred when Unit 2 did not comply with the TS LCO 3.8.4.1 ACTION a and the 7 days were exceeded for each circuit.

3. ASSESSMENT OF THE SAFETY CONSEQUENCES AND THE IMPLICATIONS OF THIS EVENT:

The OPERABILITY of the containment penetration conductor overcurzent protective devices ensures that the fault current through a containment penetration feedthrough is less than its damage curve. This design feature prevents the circuits from delivering short-circui,t currents of a magnitude and duration which could cause thermal damage to the penetrations.

The primary protective devices installed on the 31 affected circuits were OPERABLE and capable of performing their safety function. Only the added assurance of the redundant containment protective devices was in question.

Nine (9) of the circuits had required modifications completed within the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed by TS LCO 3.8.4.1. The remaining 22 circuits were deenergized and the affected systems or components were declared inoperable on March 31, 1995. Although a total of 4 circuits were not procedurally verified to be deenergized at least once per 7 days on 3 occasions, an administrative control (clearance) that was in place indicated that the circuits remained deenezgized throughout the event.

There were no adverse safety consequences or implications as a result of this event. The event did not result in any challenges to the fission product barriers or result in any releases of radioactive materials. This event did not adversely affect the safe operation of the plant oz the health and safety of the public.

CAUSE OF THE EVENT:

An independent investigation of this event is being conducted in accordance with the APS Corrective Action Program. A preliminary investigation has determined that the cause of the event is attributed to inattention to detail by the Control Room personnel performing the conditional surveillance in that they i.nappropriately N/A'd inoperable circuit breakers during the TSCCR reviews (SALP Cause Code A: Personnel Error). No common cause could be found amongst the three occurrences.

LICENSEE EVENT REPORT (LER) TEXT CONTINUATION ACIUlYNAME DOCKET NUMBER LER NUMBER PAGE YEAR SEOVENllAL RPAQO NUMBER NUMBER Palo Verde Unit.2 0 5 0 0 0 5 2 9 9 5 - 0 0 4 - 0 0 06cf07 The preliminary investigation identified several contributing factors listed below:

l. Administrative barriers such as closure reviews by Control Room supervision and surveillance reviews by the Shift Technical Advisor were not effective in identi.fying these occurrences.
2. The Control Room copy of 40TP-9ZZ04 was not corrected when the handwritten N/A's were initially discovered in the procedure on June 2, 1995 'he weeks.

Control Room copy remained inappropriately marked foz 4 more

3. When discrepancies were thought to exist between the TSCCR and the its supporting documentation regarding circuits which may or may not have the required modification, the discrepancies were not brought to resolution. Although the list of affected circuits in the TSCCR package correctly denoted the circuits which had the zequi.red modifications completed, the TSCCR list was not reconciled into a new list following each update, but marked out and annotated as to the intent of the markings.

A human performance evaluation wi,ll be performed as part of the investigation. If information is developed that would significantly affect the reader's understanding or perception of this event, a supplement will be submitted.

No unusual characteristics of the work. location (e.g., noise, heat , poor lighting) directly contributed to this event. There were no procedural errors involved.

5. STRUCTUREI SYSTEMS OR COMPONENT INFORMATION Although the containment penetration conductor overcurrent protective devices were inoperable, they did not contribute to this event. There were no component or system failures involved in this event. No failures of components with multiple functions were involved. No failures that rendered.a train of safety system inoperable were involved.

There were no safety system responses and none were necessary.

6. CORRECTIVE ACTIONS TO PREVENT RECURRENCE:

The Control Room copy of 40TP-9ZZ04 was corrected (i.e., the handwritten N/A's were removed). In addition, subsequent performances of 40TP-9ZZ04 will be controlled under the surveillance testing program. Therefore, a

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LICENSEE EVENT REPORT (LER) TEXT CONTINUATION ACIUTY NAME DOCKET NUMBER LER NUMBER PAGE

'TEAR SEQUENllAL REDO NUMBER NUMBER Paio Verde Unit 2 0 5 0 0 0 5 2 9 9 5 - 0 0 4 - 0 0 07of 0 7 controlled copy will be delivered to the Control Room by the surveillance procedure control group each time 40TP-9ZZ04 is to be performed.

A night order was issued to alert Control Room personnel of the event'nd to stress the importance of proper configuration control and attention to detail.

If necessary, coaching will be administered following the outcome of the human performance evaluation.

Other actions to prevent recurrence identified during the investigation will be tracked under the Corrective Action Tracking System.

7. PREVIOUS SIMILAR EVENTS:

Although previous events attributed to Control Room personnel error have been reported in the past three years, no events have been reported pursuant to 10CFR50.73 which involve the same cause (i.e., inappropriately N/A'ing the initial block).