05000354/LER-1997-008-01, :on 970520, C Swp Was Removed from Svc While a Pump Was Running in Manual.C Pump Automatically Restarted.Caused by Silt Accumulation Combining W/Hydraulic Perturbation.Sensing Lines Were back-flushed

:on 970520, C Swp Was Removed from Svc While a Pump Was Running in Manual.C Pump Automatically Restarted.Caused by Silt Accumulation Combining W/Hydraulic Perturbation.Sensing Lines Were back-flushed

ML20141C414
Person / Time
Site:	Hope Creek
Issue date:	06/19/1997
From:	Ritzman R Public Service Enterprise Group
To:
Shared Package
ML20141C418	List: 05000354/LER-1997-008, Forwards LER 97-008-00 Entitled, ESF Actuation: C Svc Water Pump Auto-Start. Commitments,Encl 05000354/LER-1997-008-01, :on 970520, C Swp Was Removed from Svc While a Pump Was Running in Manual.C Pump Automatically Restarted.Caused by Silt Accumulation Combining W/Hydraulic Perturbation.Sensing Lines Were back-flushed
References
LER-97-008-01, LER-97-8-1, NUDOCS 9706250169
Download: ML20141C414 (5)

LER-1997-008, on 970520, C Swp Was Removed from Svc While a Pump Was Running in Manual.C Pump Automatically Restarted.Caused by Silt Accumulation Combining W/Hydraulic Perturbation.Sensing Lines Were back-flushed

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(viii) 10 CFR 50.73(a)(2)(ii) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(iv), System Actuation 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
3541997008R01 - NRC Website

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NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 (4-93)

EXPIRES 04/30/98 EA (Y I RMAlON CCLL ON RE 5 0 HRS LICENSEE EVENT REPORT (LER)

UCYNS 8A K 7 I UZY

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(See reverse for required number of gju g g CMMgig GAS 0 5 00 N

Dg digits / characters for each block)

MANAGEMENT AND BUDGET, WASHINGTON, De 20503 FOCILITY NAME (1)

DOCKET NUMBER (2)

PAGE (3)

HOPE CREEK GENERATING STATION 05000354 1 OF 3 TITLE g4)

Engineered Safety Feature Actuation: "C' Service Water Pump Auto-Start EVENT DATE (5)

LER NUMBER (6)

REPORT DATE (7)

OTHER FACILITIES INVOLVED (8)

MONTH DAY YEAR YEAR SEQU N AL REVIS N MONTH DAY YEAR

' ' * ' ' " " ^ * '

j 05 20 97 97 -

008 00 06 19 97 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR $: (Check one or more) (11)

MODE (9) 1

' 20.2201(b) 20.2203(a)(2)(v) 50.73(a)(2)(i)(B) 50.73(a)(2)(viii)

POWER 20.2203(a)(1) 20.2203(a)(3)(1) 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)(iii) 73.71 20.2203(a)(2)(ii) 20.2203(a)(4)

)(

50.73(a)(2)(iv)

OTHER 20.2203(a)(2)(iii) 50.36(c)(1) 50.73(a)(2)(v) sp cgigb,strglow i

20.2203(a)(2)(iv) 50.36(c)(2) 50.73(a)(2)(vii)

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LICENSEE CONTACT FOR THIS LER (12)

NZE TELEPHONE NUMBER (include Area Code)

Robin Ritzman, Lead Engineer-Operational Licensing (609)339-1445

+

COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13) l COUSE SYSTEM COMPONENT MANUFACTURER RE AB E

CAUSE

SYSTEM COMPONENT MANUFACTURER R

RTABLE i

5 l

SUPPLEMENTAL REPORT EXPECTED (14)

EXPECTED MONTH DAY YEAR YES NO SUBMISSION (If yes, complete EXPECTED SUBMISSION DATE).

DATE (15)

XX XX XX i

ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16)

On May 20, 1997, at 1700, a Nuclear Controls Operator (NCO - licensed reactor operator) removed the "C"

Service Water Pump from service in I

accordance with the system operating procedure while the "A"

Service Water j

Pump was running in manual.

Three seconds after the "C"

Service Water Pump i

was stopped, the pump automatically restarted.

The auto start signal originated from a low flow signal on the "A"

Service Water Pump.

At 1707, the "C" Service Water Pump was placed in manual and successfully removed 1

from service.

All other plant equipment responded as expected.

On May 20, 1997, at 2052, a four hour notification was made in accordance with

}

10CFR50. 72 (b) (2) (ii).

The apparent cause of this event was silt accumulation combined with a hydraulic perturbation that caused the transmitter to sense a low differential pressure across the "A"

strainer, i

and provide an auto-start signal to the "C"

Service Water Pump.

The safety consequences associated with this event were minimal.

Corrective actions

include back-flushing the sensing lines, changing recurring task frequencies and evaluating potential design improvements or procedure enhancements.

This event is being reported pursuant to 10CFR50.73 (a) (2) (iv) as an event or condition that resulted in an Engineered Safety Feature actuation.

9706250169 970619 PDR ADOCK 05000354 S

PDR,

,.U.S. NUCLEAR REGULATORY COMMISSION (4-95)

LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1)

DOCKET NUMBER (2)

LER NUMBER (6)

PAGE (3)

YEAR SEQU AL R

HOPE CREEK GENERATING STATION 05000354 97 - 008 - 00 2

OF 3 TEXT (if more space is required, use additional copies of NRC Form 366A) (17)

PLANT AND SYSTEM IDENTIFICATION

General Electric - Boiling Water Reactor (BWR/4)

Station Service Water, EIIS Identifier:

BI IDENTIFICATION OF OCCURRENCE Event Date:

May 20, 1997 Problem Report:

970520334 CONDITIONS PRIOR TO OCCURRENCE The plant was in OPERATIONAL CONDITION 1 (POWER OPERATION) at 100% of rated thermal power at the time of the event.

No other structures, systems, or components were inoperable at the time of the event that contributed to the event.

DESCRIPTION OF OCCURRENCE On May 20, 1997, at 1700, a Nuclear Controls Operator (NCO - licensed reactor operator) removed the "C"

Service Water Pump from service in accordance with the system operating procedure while the "A"

Service Water Pump was running in manual.

Three seconds after the "C"

Service Water Pump was stopped, the pump automatically restarted.

The auto start signal originated from a low flow signal on the "A"

Service Water Pump.

At 1707, the "C" Service Water Pump was placed in manual and successfully removed from service.

All other plant equipment responded as expected.

On May 20, 1997, at 2052, a four hour notification was made in accordance with 10CFR50.72 (b) (2) (ii).

This event is being reported pursuant to 10CFR50. 73 (a) (2) (iv) as an event or condition that resulted in an actuation of an Engineered Safety Feature (ESP).

This ESF actuation is considered to be invalid because the actuation was in response to a spurious signal, not to an actual low flow condition.

Invalid actuation signals are reportable in accordance with 10CFR50.73 unless the signal involved only the following systems:

Reactor Water Cleanup, Control Room Emergency Ventilation, Reactor Building Ventilation, Fuel Building Ventilation, or Auxiliary Building Ventilation.

l i

r NHC FORM 366A (4-95)

,,U.S. NUCLEAR REGULATORY COMMISSION s

(4-05) i LICENSEE EVENT REPORT (LER)

TEXT CONTINUATION FACILITY NAME (1)

DOCKET NUMBER (2) l LER NUMBER (6)

PAGE (3) lvsAn as "EsT' "E**"

su l 97 - 008 -

HOPE CREEK GENERATING STATION 05000354 00 3

OF 3 TEXT (If more space is required, use additional copies of NRC Form 366A) (17)

APPARENT CAUSE OF OCCURRENCE l

The apparent cause of this event was a spurious actuation of the "C" l

Service Water Differential Pressure Transmitter caused by a normal hydraulic perturbation that occurred when the "C" Service Water Pump was secured.

Silt accumulated in the sensing lines of the pressure transmitter, which measures differential pressure across the "A" Service l

Water Strainer and provides an auto-start signal to the "C" pump on a loss-of-flow signal.

The silt accumulation and hydraulic perturbation caused the transmitter to sense a low differential pressure across the "A" strainer, and provide an auto-start signal to the "C"

Service Water Pump.

ASSESSMEN" OF SAFETY CONSEOUENCES The "C" Service Water Pump auto-started per design on a loss-of-flow signal caused by sensed low differential pressure across the "A" Service Water Strainer.

All four Service Water Pumps remained operable throughout the event.

Therefore, the safety consequences associated with this event were minimal and are limited to an unnecessary activation of an ESF component as a result of an invalid actuation signal.

PREVIOUS OCCURRENCES

LER 96-001 was submitted to discuss a Service Water Strainer failure that allowed Safety and Turbine Auxiliaries Feat Exchangers to be partially fouled with river detritus.

One of the corrective actions to this LER was to initiate recurring tasks to clean the Service Water Strainer pressure transmitter sensing lines.

These recurring tasks were scheduled at six month intervals, the recurring task for the subject transmitter was due to be performed by June 28, 1997.

As a result of this event, these recurring tasks will be performed more frequently.

CORRECTIVE ACTIONS

The transmitter sensing lines were back-flushed to remove the silt.

In addition, by August 14, 1997, the recurring tasks for performing back-flushing will be revised to be performed more frequently.

By July 31, 1997, Operations and Engineering will evaluate potential opportunities for design improvement or procedure enhancement to resolve l

the issue.