ML18153A591

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LER 96-001-00:on 951213,ESW Pump Was Inoperable Due to Loss of Missile Protection for Piping.Revised DCP 91-025.W/960215 Ltr
ML18153A591
Person / Time
Site: Surry Dominion icon.png
Issue date: 02/15/1996
From: Christian D
VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
96-069, 96-69, LER-96-001, LER-96-1, NUDOCS 9602210147
Download: ML18153A591 (6)
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Virginia Electric and Power Company :.._-

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P. 0. Box 315 Surry, Virginia 23883 February 15, 1996 U.S. Nuclear Regulatory Commission Serial No.: 96-069 Document Control Desk SPS: BCB Washington, D. C. 20555 Docket Nos.: 50-280 50-281 License Nos.: DPR-32 DPR-37

Dear Sirs:

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

REPORT NUMBER 50-280/96-001-00 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, D. A. Christian Station Manager Enclosure pc: Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 M. W. Branch NRC Senior Resident Inspector Surry Power Station 9602210147 960215 PDR ADOCK 05000280 S PDR 210072

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INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD *_. ..

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COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION '

LICENSEE EVENT REPORT (LER) AND RECORDS MANAGEMENT BRANCH (MNBB n14), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC2055!HJ001, AND TO -c' -.,,

THE PAPERWORK REDUCTION PROJECT (3150-0104), OFRCE OF -- -*,

(See reverse for required number of digits/characters for each block) MANAGEMENT AN'.) BUDGET. WASI-IINGTON, DC 2050~

FACILITY NAME (1) DOCKET NUMBER (2)  :: -*.* - _ :*.o _-*.'II P~E(3)  :*.c, ,__

Surry Power Station, Unit 1 05000 - 280 1 OF 5 **.

TITLE(4)

Emergency Service Water Pump Inoperable Due to Loss of Missile Protection for Pipina EVENT DATE 5) LER NUMBER C& REPORT DATE { n OTHER FACILmES INVOLVED (8)

MONTH DAY YEAR YEAR SEQUENTIAL REVISION MONTH DAY YEAR FACILITY NAME DOCKET NUMBER NUMBER NUMBER Surrv Unit 2 05000- 281 FACILITY NAME 12 13 95 96 -- 001 -- 00 02 15 96 DOCKET NUMBER 05000.

OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR:(Check one or more) (11)

MODE(9) N 20.402(b) 20.405(c) 50.73(a)(2)(iv) 73.71(c)

POWER 20.405(a)(1 )(i) 50.36(c)(1) 50. 73(a)(2)(v) 73.71(c)

LEVEL(10) 100% 20.405(a)(1 )(ii) 50.36(c)(2) 50.73(a)(2)(vii) OTHER 20.405(a)(1 )(iii) 50.73(a)(2)(i) 50.73(a)(2)(viii)(A) (Specify In Abstract below and X

20.405(a)(1 )(iv) 50.73(a)(2)(ii) 50. 73(a)(2)(viii)(B) In Text, NRC Fann 366A) 20.405(a)(1 )(v) 50.73(a)(2)(iii) 50.73(a)(2)(x)

NAME I(804) 357-3184 LICENSEE CONTACT FOR THIS LEA 12l TELEPHONE NUMBER (lncludlng Area Code)

D. A. Christian, Station Manager COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT t13\

CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE CAUSE SYSTEM COMPONENT MANUFACTURER REPORTABLE TONPRDS TONPRDS SUPPLEMENTAL REPORT EXPECTED l14\ I EXPECTED I MONTI-I I DAY I YEAR I~ ...unnl&te EXPECTED SUBMISSION DATE XINO I SUBMISSION DATE (15) I I I ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)

On December 13, 1995, with Units 1 and 2 operating at 100% power, a trench was excavated to facilitate the replacement of a section of Unit 1 Fish Screen {FS} system piping. On January 17, 1996, Engineering and Site Services personnel recognized that the trench was aligned with the discharge piping from Emergency Service Water Pump {ESWP} 1-SW-P-1 A and that the minimum depth of soil cover {i.e., ~ 5 feet} required for missile protection was not in place.

ESWP 1-SW-P-1 A was declared inoperable at 1450 hours0.0168 days <br />0.403 hours <br />0.0024 weeks <br />5.51725e-4 months <br />. Compensatory measures were established and ESWP 1-SW-P-1A was returned to an operable status on January 17, 1996, at 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br />.

A Root Cause Evaluation {RCE} was performed. The RCE concluded that this event was caused by a personnel error during a revision of the associated Design Change Package

{DCP}. To prevent recurrence, coaching will be provided to engineering personnel involved in the design change process to reinforce the requirements related to the DCP revision process.

In addition, the procedures used to conduct excavation activities will be revised to verify that required missile protection is maintained. This event resulted in no safety consequences since no severe weather conditions occurred and the probability *of a tornado generated missile striking the subject ESWP piping was negligible. This report is being submitted pursuant to 10 CFR 50.73{a}{2)(i}{B}.

NRC FORM 388 (S-92)

NRCFORM366 U.S. NUCLEAR REGULATORY COMMISSION .APPROVED BY 0MB NO. 3150-0104

  • .. _ -* EXPIRES 5/31/95 *..*, ** ..

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ESTIMATED BURDEN PER RESPONSET0°COMPLYWITH~IS ". '

INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION LICENSEE EVENT REPORT (LER) AND RECORDS MA"IAGEMENT BRANCH (MNBB n14), U.S. NUCLEAR' REGULATORY COMMISSION, WASHINGTON, DC 20555-0001, AND TO THE PAPE"'WORK REDUCTION PROJECT (3150-0104), OFFICE OF (See reverse ir *~uired number of digits/characters for each block) W,NAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME (11 DOCKET NUMBER 121 LER NUMBER 181 PAGE 131 YEAR SEQUENTIAL NUMBER REVISION NUMBER Surry Power Station, Unit 1 05000 - 280 96 - 001 - 00 2oF5 TEXT (II more space Is required, use addlttonal copies of NRC Form 366A) (17}

1.0 DESCRIPTION

OF THE EVENT On December 13, 1995, with Units 1 and 2 operating at 100% power, a trench was excavated to facilitate the replacement of a section of Unit 1 Fish Screen (FS) system piping [EIIS-KE,PSP]. The existing carbon steel FS piping had become degraded and was being replaced with fiberglass piping, as specified by Design Change Package 91-025.

The nonsafety-related FS system supplies brackish river water to clean the screens and to flush the flumes at the circulating/service water intake structure [EIIS-NN,MK]. The system also supplies cooling water to the circulating water pump lube oil coolers.

The excavation was performed in accordance with the requirements of General Maintenance Procedure GMP-C-102, Excavation, Backfill, and Subgrade Preparation. The trench was approximately 6 feet wide, 40 feet long, and 46 inches deep, with steel plate covering about 12 linear feet to permit the passage of vehicle traffic. These dimensions remained constant until January 8, 1996 when approximately six inches of sand was added to provide bedding material for the new FS piping.

On January 10, 1996 an Installation Problem Report (IPR) was submitted which identified an electrical conduit that crossed the trench and interfered with the FS piping installation.

Engineering reviewed the IPR and concluded that the FS piping would need to be routed below the electrical conduit. As a result, an approximately 20 foot portion of the trench was excavated further to a depth of about 65 inches on January 16, 1996.

On January 17, 1996, Engineering and Site Services personnel were inspecting the area and recognized that the trench was aligned with the discharge piping from Emergency Service Water Pump 1-SW-P-1 A [EIIS-81,PSP]. Upon further investigation, it was determined that the ESWP discharge piping in the deeper portion of the trench (about 20 feet in length) had approximately eight to ten inches of soil cover. The balance of the ESWP piping in the trench had approximately 34 inches of soil cover. A Deviation Report was submitted since the minimum depth of soil cover (i.e., ~ 5 feet) required for missile protection was not in place. ESWP 1-SW-P-1A was declared inoperable at 1450 hours0.0168 days <br />0.403 hours <br />0.0024 weeks <br />5.51725e-4 months <br />.

NRC FORM 386A (S-92)

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NRC FORM366 U.S. NUCLEAR REGULATORY COMMISSION

    • APPROVED BY 0MB NO. 3150-0104 (5:92) _.- _- _, .*._ --*: *:EXPIRES 5/31/~

ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD .-

COMMENTS REGARDING DURDEN ESTIMATE TO THE INFORMATION *,

LICENSEE EVENT REPORT (LER) AND RECORDS MANAGEMENT BRANCH (MNBB nt4), U.S. NUCLEAR REGULATORY COMMISSION. WASHINGTON, DC ~ 1 . AND TO TW PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF (Sae reverse for required number of di11tts,*,:haracters for each biock) MANAGEMENT AND _BUDGET, WASHINGTON, DC 20503.

FACILITY NA11E 111 DOCKET NUMBER 121 LER NUUBER (11'1 PAGE 131 YEAR SEQUENTIAL NUMBER REVISION NUMBER Surry Power Station, Unit 1 05000 - 280 96 - 001 - 00 3oF5 TEXT (If more space Is required, use additional copies of NRC Form 388A) (17)

1.0 DESCRIPTION

OF THE EVENT (Continued)

DCP 91-025 was promptly revised to incorporate compensatory measures that would be required in the event that a tornado watch was posted for the area. Personnel and equipment were staged to implement the compensatory measures and ESWP 1-SW-P-1 A was returned to an operable status on January 17, 1996, at 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br />.

A Root Cause Evaluation (RCE) team was established on January 18, 1996 to determine the cause of this event and to develop recommendations to prevent recurrence. The RCE team determined that the missile protection for the ESWP 1-SW-P-1 A discharge piping had been degraded from December 13, 1995 to January 17, 1996. This condition exposed the ESWP piping to potential missile hazards which could have damaged the line, resulting in ESWP 1-SW-P-1 A being unable to perform its design function. The RCE team also reviewed the operating history of ESWPs 1-SW-P-1 B and 1-SW-P-1 C for the subject period. The team noted that ESWP 1-SW-P-1C had been removed from service on two occasions during the period to perform maintenance.

Technical Specifications 3.14.8 permits one ESWP to remain inoperable for a period not to exceed seven days. During this event, ESWP 1-SW-P-1 A was effectively rendered inoperable for 36 days and ESWP 1-SW-P-1 C was inoperable concurrently for approximately 33 hours3.819444e-4 days <br />0.00917 hours <br />5.456349e-5 weeks <br />1.25565e-5 months <br />. Therefore, this report is being submitted pursuant to 10 CFR

50. 73(a)(2)(i)(B) as a condition prohibited by Technical Specifications.

2.0 SIGNIFICANT SAFETY CONSEQUENCES AND IMPLICATIONS This event resulted in no safety consequences or significant implications. During the period of concern, the meteorological conditions that require entry into Abnormal Procedure O-AP-37.01, Abnormal Environmental Conditions, (including tornado watches or warnings) were not experienced. In addition, the steel plate that covered a 12 foot portion of the trench provided adequate missile protection for the ESWP 1-SW-P-1 A discharge piping below it. Furthermore, partial missile protection was maintained for the balance of the ESWP piping throughout the period.

NRC FORM 368A (5-92)

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NRCFORM366 (5-92)

    • U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB NO. 3150-0104
  • , -EXPIRES-5/31/95 - - _*:* .' *,

ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS INFORMATION COLLECTION REQUEST: 50.0 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION __

LICENSEE EVENT REPORT (LER) AND RECORDS MANAGEMENT BRANCH (MNBB n14), U.S. NUCLEAR REGULATORY COMMISSION, WASHINGTON, DC 20555.()001, AND TO mr PAPERWORK REDUCTION PROJECT (3150-0104), OFFICE OF (Se a reverse for required number of digits/characters for each block) MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME 111 DOCKET NUIIBER 121 LER NUIIBER (6) PAGE (3)

YEAR SEQUENTIAL NUMBER REVISION NUMBER Surry Power Station, Unit 1 05000 - 280 96 - 001 - 00 40F5 TEXT (If more space Is required, use additional copies of NRC Form 366A) (17) 2.0 SIGNIFICANT SAFETY CONSEQUENCES AND IMPLICATIONS (Continued)

The likelihood of a tornado generated missile striking the subject ESWP piping was negligible. The Surry UFSAR estimates that the probability of a tornado striking any point at the plant site is 1. 73 E-5 per year. An engineering evaluation concluded that the probability of such an event would be significantly less (< 2.8 E-7) during the period of concern, since it did not correspond to the tornado season in this area. Therefore, the health and safety of the public were not affected at any time during this event.

3.0 CAUSE The RCE team concluded that this event was caused by an error on the part of utility engineering personnel during a revision of DCP 91-025, which included the replacement of the subject FS system piping. Specifically, the requirements of General Nuclear Standard STD-GN-0001, Instructions for DCP Preparation, were not fully implemented in that the loss of missile protection for the subject ESWP piping was not considered. The individuals involved were focused on the FS system modifications and did not recognize that the associated excavation activities would degrade the missile protection for the ESWP 1-SW-P-1 A discharge piping.

The RCE also identified that the procedures used to conduct the excavation activities did not address the potential for a loss of missile protection. This procedural omission is considered a weakness that contributed to this event.

4.0 IMMEDIATE CORRECTIVE ACTION(S)

ESWP 1-SW-P-1A was declared inoperable on January 17, 1996 at 1450 hours0.0168 days <br />0.403 hours <br />0.0024 weeks <br />5.51725e-4 months <br /> and a Limiting Condition for Operation was entered in accordance with Technical Specifications 3.14.B.

DCP 91-025 was promptly revised to incorporate the compensatory measures that would be required in the event that a tornado watch was posted for the area. Personnel and equipment were staged to implement the compensatory measures and ESWP 1-SW-P-1 A was returned to an operable status on January 17, 1996, at 2000 hours0.0231 days <br />0.556 hours <br />0.00331 weeks <br />7.61e-4 months <br />.

NRC FORM 366A (5-92)

  • U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB NO. 315CM>104 * - * *

- * - EXPIRES 5/31/95 : >

ESTIMATED BURDEN PER RESPONSE TO COMPLY WITH THIS

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INFORMATION COUECTION REQUEST: 50.0 HRS. FORWARD COMMENTS REGARDING BURDEN ESTIMATE TO THE INFORMATION :,,*:

LICENSEE EVENT REPORT (LER) AND RECORDS MANAGEMENT BRANCH (MNBB 7714), U.S. NUCLEAR-. -

REGULATORY COMMISSION, WASHINGTON, DC 2CJ555.0001, AND TO THE PJ PERWORK REDUCTION PROJECT (3150-0104), OFFICE OF (See reverse for required number of dlgi1s/characters for each block) MANAGEMENT AND BUDGET, WASHINGTON, DC 20503.

FACILITY NAME ft) DOCKET NUMBER 121 LER NUUBER rm PAGE 131 YEAR SEQUENTIAL NUMBER REVISION NUMBER Surry Power Station, Unit 1 05000 - 280 96 - 001- 00 50F5 TEXT (If mora space Is required, use additional copies ol NRC Fenn 368A) (17) 5.0 ADDITIONAL CORRECTIVE ACTIONS An RCE team was established on January 18, 1996 to determine the cause of this event and to develop recommendations to prevent recurrence. The team presented the results of its investigation to the Station Nuclear Safety and Operating Committee on February 8, 1996. The resulting corrective actions are discussed in Section 6.

Missile protection for the ESWP 1-SW-P-1 A discharge piping was restored on February 1, 1996.

6.0 ACTIONS TO PREVENT RECURRENCE Procedures used to conduct excavation activities will be revised to include a requirement to verify that the potential for a loss of missile protection is considered prior to the start of such activities.

Coaching will be provided to engineering personnel involved in the design change process to reinforce the requirements of General Nuclear Standard STD-GN-0001, regarding the DCP revision process.

7.0 SIMILAR EVENTS A portion of the Unit 2 Auxiliary Feedwater System full flow recirculation line was uncovered during an excavation activity on June 15, 1992. The removal of the soil cover degraded the missile protection for the subject line. This condition placed the line outside of the system's design basis. The cause of this event was identified as a failure to follow procedures by the individuals involved with the excavation activity. Licensee Event Report (LER) 50-281/92-007-00 reported this event pursuant to 10 CFR 50.73(a)(2)(i)(B).

8.0 MANUFACTURER/MODEL NUMBER NIA NRC FORM 366A (5-92)

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