ML18009A936
| ML18009A936 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 06/14/1991 |
| From: | Richey R CAROLINA POWER & LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| H-910079-(O), H0-910079-(O), NUDOCS 9106190174 | |
| Download: ML18009A936 (3) | |
Text
ACCELERATED DISTRIBUTION DEMONSTRION SYSTEM REGULATORY XNFORMATION DXSTRIBUTION SYSTEM (RIDS)
ACCESSION NBR:9106190174 DOC.DATE: 91/06/14 NOTARXZED: NO FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina AUTH.NAME AUTHOR AFFILIATION RICHEY,R.B.
Carolina Power 6 Light Co.
RECIP.NAME RECIPIENT AFFILXATION Document Control Branch (Document Control Desk)
DOCKET g
05000400
SUBJECT:
Special rept:on 910516,plant experienced LTOP event while RCS operated under solid water conditions. Actuation of LTOP sys resulted from pressure induced by start of reactor coolant pump.
DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE:
TITLE: 50.73/50.9 Licensee Event Report (LER), Incident Rpt, etc.
NOTES:Application for permit renewal filed.
D
/
05000400 RECIPIENT ID CODE/NAME PD2-1 LA MOZAFARX,B.
INTERNAL: ACNW AEOD/DOA AEOD/ROAB/DSP NRR/DET/EMEB 7E NRR/DLPQ/LPEB10 NRR/DREP/PRPB11 NRR/DST/SICB8H3 NRR/DST/SRXB 8E RES/DSIR/EIB EXTERNAL: EG&G BRYCE,J.H NRC PDR NSIC POORE,W.
COPIES LTTR ENCL 1
1 1
1 2
2 1
1 2
2 1
1 1
1 2
2 1
1 1
1 1
1 3
3 1
1 1
1 RECXPIENT ID CODE/NAME PD2-1 PD ACRS AEOD/DSP/TPAB NRR/DET/ECMB 9H NRR/DLPQ/LHFB10 NRR/DOEA/OEAB NRR/DST/SELB 8D NRR/DST SPLB8D1 E
02 FILE 01 L ST LOBBY WARD NSIC MURPHYiG A NUDOCS FULL TXT COPIES LTTR ENCL 1
1 2
2 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 1
1 D
D D
NOTE TO ALL"RIDS" RECIPIENTS:
D D
PLEASE HELP US TO REDUCE WASTEl CONTACT THE DOCUMENT CONTROL DESK, ROOM P 1-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEEDI TOTAL NUMBER OF COPIES REQUIRED:
LTTR 33 ENCL 33
Carolina Power 5 Light Company P.O. Box 165 ~ New Hill,N.C. 27562 R. B. RICHEY Vice President Harris Nuctear Project HARRIS NUCLEAR PROJECT P.O.
Box 165 New Hill, NC 27562 JUN f 4 199I Letter Number:
HO-910079 (0)
United States Nuclear Regulatory Commission Document Control Desk Washington, D.C. 20555 SHEARON HARRIS NUCLEAR POWER PLANT Docket No. 50-400, License NPF-63 NRC 30 DAY SPECIAL REPORT In accordance with Technical Specifications 3.4.9.4 and 6.9.2 for the Shearon Harris Nuclear Plant, Carolina Power
& Light Company herewith submits this Special Report.
This Special Report contains information on the activation of the Low-Temperature, Over"Pressure Protection System on May 16, 1991.
Very Truly yours, R. B. Richey Vice President Harris Nuclear Project MGW:dmw Enclosure cc'Mr. S.
D. Ebneter Ms. B. L. Mozafari Mr. J.
E. Tedrow 9106190174 910614 PDR ADOCK 05000400 PDR WEM/HO-9100790/1/OS1
<4 V '
g
PORV ACTUATION SPECIAL REPORT Descri tion of Circumstances Initiatin the Transient:
On May 16, 1991, at 1310, the plant experienced a low temperature, over-pressure (LTOP) event while the Reactor Coolant System was being operated under solid water conditions.
The actuation of the LTOP system resulted from a
pressure transient induced by the start of a Reactor Coolant Pump (RCP).
The plant was in Mode 5 on May 16, 1991, to repair a steam leak on IRC-117, the block valve for the pressurizer power operated relief valve (PRZ PORV)
PCV-445A.
Procedure GP-007, Plant
- Cooldown, was used to place the plant'n Mode 5.
Degas of the Reactor Coolant System (RCS) was commenced to accommodate maintenance on 1RC" 117.
- However, degassing had not progressed as expected when Mode 5
was reached.
- Thus, degassing continued while Operations management considered alternate degas methods.
The operations shift was directed to (a) minimize letdown and charging such that the volume control tank (VCT) could be degassed to a concentration (4X) at which'ydrogen peroxide could be introduced, and (b) start a
RCP to aid the time for degassing.
The shift discussed the starting of a
RCP while in solid plant conditions and reviewed applicable procedures to ensure all prerequisites were met.
The RCS was pressurized for an attempt to start the A loop RCP.
Letdown flow was increased while pressure control valve, PCV-145, was controlling pressure and letdown.
RCS temperature was approximately 130'F.
Approximately 30 seconds after RCP A was
- started, RCS pressure increased rapidly, and the LTOP system actuated appropriately to relieve the transient pressure.
The operator recognized the event and verified proper operation of PCV-445A and PCV-145.
The operator then took manual control of PCV-145 in order to dampen the transient.
Effect of PORV's on the Transient:
The LTOP System actuated automatically as required.
RCS Pressure reached the 390 psig setpoint for PCV-445A and the pressure transient was relieved sufficiently such that the backup PORV with a setpoint of 400 psig did not have to actuate.
h Corrective Action to Prevent Recurrence:
Discussions were held with the shift crew involved to ensure that sufficient briefings are performed prior to task performance, and that every available precaution is exercised to prevent an LTOP actuation when similar RCS conditions exist in the future.
The observed energy transient will be evaluated and operating procedures will be strengthened based on the results of the evaluation.
MEM/HO-9100790/2/OS1