ML18101A560
| ML18101A560 | |
| Person / Time | |
|---|---|
| Site: | Salem  |
| Issue date: | 02/15/1995 |
| From: | Summers J Public Service Enterprise Group |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| 95-01, 95-1, NUDOCS 9502240296 | |
| Download: ML18101A560 (3) | |
Text
- PS~G Public; Service Electric and Gas Company P.O. Box 236 Hancocks Bridge, New Jersey 08038-0236 Nuclear Business Unit U. s. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555
Dear Sir:
SALEM GENERATING STATION LICENSE NO. DPR-75 DOCKET NO. 50-311 UNIT NO. 2 SPECIAL REPORT 95-01 February 15, 1995 This Special Report addresses the actuation of the Salem Unit 2 Pressurizer Overpressure Protection System to mitigate a Reactor Coolant System pressure transient, which occurred while in Operational Mode 5.
This report is submitted pursuant to Technical Specification 6.9.2 and in accordance with Technical Specification 3.4.10.3, Action d.
SORC Mtg.95-021 MJPJ:pc Distribution 9502240296 950215 PDR ADOCK 05000311 S
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"'~ *J,;'... ; \\; l~ 0 Sincerely yours, J. c. Summers General Manager -
Salem Operations
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95-2168 REV. 6/94
' i SPECIAL REPORT 311/95-01 PLANT IDENTIFICATION:
Salem Generating Station - Unit 2 Public Service Electric & Gas Company Hancock's Bridge, New Jersey 08038 IDENTIFICATION OF OCCURRENCE:
Pressurizer Overpressure Protection System Channels I And II Actuation Date of Occurrence: 1/25/95 Report Date:
2/15/95 This report was initiated by Incident Report No.95-045 CONDITIONS PRIOR TO OCCURRENCE:
Mode 5 - Reactor Power Level % - Unit Load Mwe Unit 2 refueling/maintenance outage 2R8 was in progress and 21 reactor coolant pump (RCP) and 22 Residual Heat Removal (RHR) pump were in service.
Reactor Coolant System (RCS) temperature was approximately 185 degrees Fahrenheit (F)
DESCRIPTION OF OCCURRENCE:
At approximately 1043 hours0.0121 days <br />0.29 hours <br />0.00172 weeks <br />3.968615e-4 months <br /> on January 25, 1995, 21 RCP was turned off to remove it from service.
Shortly thereafter, a momentary RCS pressure transient occurred and pressure peaked at 365.5 psig.
Both pressurizer power operated relief valves, 2PR1 and 2PR2, automatically opened in response to a Pressurizer Overpressure Protection System (POPS) Channels I and II actuation signal.
APPARENT CAUSE OF OCCURRENCE:
This occurrence resulted from pressure equalization through the 21 RCS loop shortly after 21 RCP was turned off.
With only 21 RCP running, a pressure drop of approximately 16.5 psi is present in the RCS. loop hot leg which contains the RHR suction and the POPS pressure transmitters (PTs).
As
APPARENT CAUSE OF OCCURRENCE:
(cont'd) such, when the pump was turned off a corresponding pressure rise of 16.5 psi occurred, causing the POPS pressure transmitters, PT403 and PT405, to actuate.
ANALYSIS OF OCCURRENCE:
When 21 RCP was turned off, the pressure drop present in the 21 RCS loop was effectively recovered.
This pressure recovery resulted in a corresponding increase in the pressure sensed by the POPS' Channels I and II pressure transmitters causing them to actuate, in accordance with design.
Per Safety Parameter Display System data, the pressure at POPS PT403 increased from 350.5 to 360.8 psig and the pressure at POPS PT405 increased from 355.6 to 365.5 psig.
As such, the incurred 4.5 psi difference between the peak recorded pressure of 365.5 psig and the setpoint of 370 psig for POPs actuation was within the allowable actuation tolerance of the POPS PTs and the Technical Specification requirement of less than or equal to 375 psig for POPS actuation.
CORRECTIVE ACTION:
Appropriate procedure changes will be made to: 1) require reducing RCS pressure to approximately 340 psi prior to removing a sole running 21 RCP or 11 RCP (Unit 1) from service; and, 2) add a caution to expect an RCS pressure increase when removing a sole running 21 RCP or 11 RCP (Unit 1} from service.
This occurrence will be reviewed in training.
SORC Mtg.95-021 MJP:pc Genera Manager -
Salem Operations