ML18153A124

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LER 97-002-01:on 970116,one Train of Auxiliary Ventilation Sys Was Inoperable Outside of Ts.Caused by Personnel Error. Submitted Deviation Rept Re Reverse Rotation of Fan & Work Request to Adjust linkage.W/970408 Ltr
ML18153A124
Person / Time
Site: Surry Dominion icon.png
Issue date: 04/08/1997
From: Christian D
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
97-106A, LER-97-002, LER-97-2, NUDOCS 9704150060
Download: ML18153A124 (5)
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10CFR50.73 Virginia Electric and Power Company Surry Power Station 5570 Hog Island Road Surry, Virginia 23883 April 8, 1997 U. S. Nuclear Regulatory Commission Serial No.: 97-106A Document Control Desk SPS:VLA

Dear Sirs:

Pursuant *to Surry Power Station Technical Specifications, Virginia Electric and Power Company hereby submits the following updated Licensee Event Report applicable to Surry Power Station Units 1 and 2.

REPORT NUMBER 50-280/50-281 /97-002-01 This report has been reviewed by the Station Nuclear Safety and Operating Committee and will be forwarded to the Management Safety Review Committee for its review.

Very truly yours, 1~~

D. A Christian Station Manager Enclosure Commitments contained in this letter: None copy: Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 R. A. Musser NRG Senior Resident Inspector Surry Power Station 150006 9704150060 970408 \\\\II\ \\Ill \}II\\}\\\ \\Ill \\I~\}\\\ \\I\\ \I\\\~\\\\\I PDR ADOCK 05000280 S PDR

'<1 NRC FORM366 U.S. UCLEAR REGULATORY COMMISSION (4-95) APPROVED BY 0MB NO. 3160-0104 EXPIRES 4/30/98

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ESTIMATED BURDEN PER RESPONSE TO COMPLY WllH lHIS MANDATORY INFORMATION COLLECTION REQUEST: 50.0 HRS.

LICENSEE EVENT REPORT (LER) REPORTED LESSONS LEARNED ARE INCORPORATED INTO lHE LICENSING PROCESS AND FED BACK TO INDUSTRY. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO lHE INFORMATION AND RECORDS MANAGEMENT BRANCH (Nl F33),

(See reverse for required .number of digits/characters for each block) U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO lHE PAPERWORK REDUCT10N PROJECT (3150-0104), OFFICE OF t.WlAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (1) DOCKET NUMBER (2) PAGE(3)

SURRY POWER STATION, Unit 1 05000-280 I 1 OF4 TITLE (4)

One Train of Auxiliary Ventilation System Inoperable Outside of TS EVENT DATE (5) LER .... -* " REPORT DATE (7) OTHER FACILITIES INVOLVED 8)

SEQUENTIAL REVISION FACILITY NAME DOCUMENT NUMBER MONTH DAY YEAR YEAR MONTH DAY YEAR NUMBER NUMBER Surry Unit 2 05000-281 FACILITY NAME DOCUMENT NUMBER 01 . 16 97 97 -002- 1 04 08 97 05000-OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check one or more) (11)

MODE (9) N 20.2201(b) 20.2203(a)(2)(v) X 50. 73(a)(2)(i) 50. 73(a)(2)(viii)

POWER 20.2203(a)(1) 20.2203(a)(3)(i) 50. 73(a)(2)(ii) 50.73(a)(2)(x)

LEVEL (10) 100% 20.2203(a)(2)(i) 20.2203(a)(3)(ii) 50. 73(a)(2)(lil) 73.71 20.2203(a)(2)(iQ 20.2203(a)(4) 50. 73(a)(2)(iv) OTHER 20.2203(a)(2)(iii) 50.36(c)(1)

  • 50.73(a)(2)(v) Specify in Abstract below 20.2203(a)(2)(1v) 50.36(c)(2) 50. 73(a)(2)(vli) or in NRC Form 366A NAME LICENSEE CONTACT FOR THIS LER 12 I TELEPHONE NUMBER Qnclude Area Code)

D. A. Christian, Station Manager (757) 365-2000 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)

CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE I

TONPRDS TONPRDS SUPPLEMENTAL REPORT EXPECTED (14) EXPECTED MONTH DAY YEAR I YES (If yes, complete EXPECTED SUBMISSION DATE).

I.XI NO SUBMISSION DATE ABSTRACT (Limit to 1400 spaces, I.e., approximately 15 single-spaced typewritten lines) (18)

On January 9, 1997, with Unit 1 and Unit 2 at .100% power, a 7 day Limiting Condition of Operation (LCO) was entered at 0508 hours0.00588 days <br />0.141 hours <br />8.399471e-4 weeks <br />1.93294e-4 months <br /> for auxiliary ventilation system filter exhaust fan 01-VS-F-588 maintenance. On January 10, 1997, the actuator for 1-VS-MOD-588 was replaced with a rebuilt actuator and the linkage was adjusted. Following completion of the specified testing, the fan was declared operable on January 15, 1997. On January 16, 1997 reverse rotation of 1-VS-F-588 was observed. The fan was declared inoperable and 1-VS-MOD-588 was adjusted, eliminating the reverse rotation of the 588 fan. The fan was declared operable at 1257 hours0.0145 days <br />0.349 hours <br />0.00208 weeks <br />4.782885e-4 months <br /> on January 16, 1997.

On February 7, 1997, it was determined that the misalignment of 1-VS-MOD-588, which had existed on January 15,1997, rendered the fan inoperable and that the 7 day LCO that was entered on January 9, 1997 for maintenance should not have been exited until full damper closure was properly verified. This occurred 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> 49 minutes after the expiration of the 7 day LCO, exceeding the 6 hour6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> requirement of TS 3.22 requiring the units to be in Hot Shutdown. The auxiliary ventilation system was capable of performing its safety function during this event. Therefore, the health and safety of the public were not affected. This event is being reported in accordance with 10 CFR l50.73(a)(2)(i)(B) for operating in a condition prohibited by TS.

NRC FORM 366 (4-95)

'- r . = = = = = = = = = = = = = = ;

NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (4-95)

. LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) DOCKET LER NUMBER (6) PAGE (3)

Surry Power Station, Unit 1 YEAR I SEQUENTIAL NUMBER l REVISION NUMBER 05000-280

  • 97 --002-- 1 2 OF 4 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

1.0 DESCRIPTION

OF THE EVENT Technical Specifications (TS) 3.22.A requires that whenever either unit's Reactor Coolant System {EIIS-A8} is greater than 350 degrees Fahrenheit and 450 psig, two auxiliary.

ventilation exhaust filter trains {EIIS-VF} shall be operable. TS 3.22.8 requires that with one train of the exhaust filter system inoperable for any reason, the inoperable train must be returned to an operable status within 7 days or the unit placed in Hot Shutdown within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

On January 9, 1997, with Unit 1 and Unit 2 at 100% power, a 7 day Limiting Condition of Operation (LCO) was entered at 0508 hours0.00588 days <br />0.141 hours <br />8.399471e-4 weeks <br />1.93294e-4 months <br /> for auxiliary ventilation system filter exhaust fan I 01-VS-F-588 planned maintenance. On January 10, 1997, the actuator for 1-VS-MOD-588 was replaced with a rebuilt actuator and the linkage was adjusted. At 0509 hours0.00589 days <br />0.141 hours <br />8.416005e-4 weeks <br />1.936745e-4 months <br /> on January 13, 1997, it was noted that the 588 fan was rotating* in the reverse direction at 13 rpm prior to aligning dampers for the fuel building suction path. After the dampers were aligned, the fan stopped rotating in the reverse direction. Engineering was contacted and it was determined that the fan could be started as long as reverse rotation was less than 125 rpm. A Deviation Report on the* reverse rotation of the fan and a Work Request to adjust the linkage were submitted. Upon completion of previously scheduled fan maintenance and successful completion of Operations Periodic Tests O-OPT-VS-002, Auxiliary Ventilation Filter Train Test, and O-OPT-VS-007, Auxiliary Ventilation Filter Flow Test, the 7 day LCO was exited at 0752 hours0.0087 days <br />0.209 hours <br />0.00124 weeks <br />2.86136e-4 months <br /> on January 15, 1997. No reverse rotation had been noted during the return to service testing which in part verified there had been no rotation 60 minutes after stopping the fan.

However, the return to service testing did not have the ventilation system in an alignment that would create a back pressure sufficient to cause backward rotation of the 588 fan.

On January 16, 1997 at 0100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br />, 1-VS-F-588 was again discovered to be rotating in the reverse direction at 23 rpm with the SBA fan not operating. The 588 fan was declared inoperable at 0716 hours0.00829 days <br />0.199 hours <br />0.00118 weeks <br />2.72438e-4 months <br /> and a 7 day LCO was entered in accordance with TS 3.22. Further evaluation completed on February 7, 1997, concluded that if an automatic demand had occurred and the 58A fan was operating, the reverse rotation of the 588 fan could have increased to a speed where the 588 fan may not have started or continued to operate, thereby rendering the 588 fan inoperable. It was subsequently determined that this reverse rotatioi, was due to leakage through damper 1-VS-MOD-588. The damper actuator linkage* was adjusted so that the damper would close fully. The 7 day LCO was exited at 1257 hours0.0145 days <br />0.349 hours <br />0.00208 weeks <br />4.782885e-4 months <br /> on January 16, 1997 following return to service testing. There was no reverse rotation noted on I the 58A or 588 fans with the opposite fan operating at that time.

The maintenance performed on 1-VS-MOD-588 on January 10, 1997 resulted in the damper not fully closing allowing reverse rotation of the fan. An evaluation completed on February 7, I 1997 determined that this condition rendered the 588 fan inoperable. The 7 day LCO that was entered on January 9, 1997 when the 588 fan was removed from service for maintenance should not have been exited until full damper closure was properly verified. The damper was NRC FORM 366A (4-95)

~ r.==============;

NRC FORM 366A .S. NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER) .

TEXT CONTINUATION FACILITY NAME (1) DOCKET LER NUMBER (6)

  • PAGE (3)
  • Surry Power Station, Unit 1 YEAR I SEQUENTIAL NUMBER I REVISION NUMBER 05000-280 97 --002-- 1 3 OF. 4 TEXT (If more space is required, use additional copies of NRC Form 366A) (17) properly adjusted* and the 588 fan was declared operable at 1257 hours0.0145 days <br />0.349 hours <br />0.00208 weeks <br />4.782885e-4 months <br /> on January 16, 1997..

This was 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br /> 49 minutes after the expiration of the 7 day LCO, exceeding the six hour requirement of TS 3.22 requiring the units to be in Hot Shutdown.

  • I This event is being reported in accordance with 10 CFR 50.73(a)(2)(i)(8) for operating in a condition prohibited by TS.

2.0 SAFETY CONSEQUENCES AND IMPLICATIONS Each of the auxiliary ventilation filtered exhaust trains, 3A and 38, consists of an exhaust fan, prefilters, a high efficiency particulate absolute filter, and a charcoal adsorber assembly. The purpose of the filtered exhaust trains is to provide standby capability for removal of particulate and iodine contaminants. The filter trains a*re capable of filtering the exhaust from the charging pump cubicles of the auxiliary building, the fuel building, the decontamination building, the safeguards building, and the containment (during shutdown).

IThe safety analysis for Loss of Coolant Accident dose considerations assumes that any Emergency Core Cooling System (ECCS) leakage will be filtered. During the period when the 588 fan was inoperable, the capability to filter any ECCS leakage and other exhaust was maintained by the 58A fan. The auxiliary ventilation filtered exhaust trains also provide cooling to the aligned ventilated areas. It has been determined that there would have been adequate flow from the SBA fan to provide cooling to the required components. Therefore, the SBA fan was capable of performing its specified function; and the health and safety of the public were not affected.

In addition, there was no accident condition present during this event, . and the auxiliary ventilation system was not required to fulfill its intended function'.

3.0 CAUSE'1 The cause of this event was personnel error in that the Post Maintenance Testing did not identify specific system test alignments to assure proper damper closure.

A contributing cause of the event was that the effect of the misaligned damper on the operability of the 588 fan was not recognized. The misaligned damper caused the 588 fan to be inoperable due to reverse rotation.

NRC FORM 366A (4-95)

  • - r.==============4 NRC FORM 366A U.S. NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1) DOCKET LER NUMBER (6) PAGE (3)

Surry Power Station, Unit 1 YEAR I SEQUENTIAL NUMBER I REVISION NUMBER 05000-280 97 --002-- 1 . 4 OF 4 TEXT (If more space is required, use additional copies of NRC Form 366A) (17) 4.0 IMMEDIATE CORRECTIVE ACTION(S)

After discussions with Engineering on January 13, 1997, a Deviation Report regarding the reverse rotation of the fan and a Work Request to adjust the linkage were submitted.

On January 16, 1997 at 0716 hours0.00829 days <br />0.199 hours <br />0.00118 weeks <br />2.72438e-4 months <br />, a 7 day LCO was entered when it was determined that the 588 fan was inoperable due to rotation in the reverse direction at 23 rpm with the 58A fan not I operating. A Deviation Report was submitted. This reverse rotation was subsequently determined to be due to improper adjustment of damper 1-VS-MOD-588. The damper was properly adjusted and the 7 day LCO was exited at 1257 hours0.0145 days <br />0.349 hours <br />0.00208 weeks <br />4.782885e-4 months <br /> on January 16, 1997 following return to service testing.

5.0 ADDITIONAL CORRECTIVE ACTION(S)

On January 17, 1997 at 1347 hours0.0156 days <br />0.374 hours <br />0.00223 weeks <br />5.125335e-4 months <br />, the fuel building was placed on filtered exhaust using the 58A fan. The auxiliary building _operator physically verified that the 588 fan was not rotating in the reverse direction when back pressure was introduced by operating the 58A fan while it was I aligned to the fuel building.

  • 1 The operating logs were revised to reflect that if any reverse rotation of either of the 58 fans is observed the Shift Supervisor will be notified to evaluate operability.

6.0 ACTIONS TO PREVENT RECURRENCE Return to service tests for the auxiliary ventilation system were reviewed to ensure that testing methods are appropriate. Post Maintenance Testing (PMT) was revised to identify specific test alignments in order to specifically address reverse rotation considerations on fan operability.

Following damper adjustment, the PMT verifies the damper is properly sealing by checking for reverse rotation with the opposite fan running while aligned to create back pressur~.

7.0 SIMILAR EVENTS

.None 8.0 MANUFACTURER Not Applicable NRC FORM 366A (4-95)

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