ML031110190
| ML031110190 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 04/15/2003 |
| From: | Beckner W NRC/NRR/DRIP/RORP |
| To: | Joseph Holonich NRC/NSIR/DIRO |
| References | |
| FOIA/PA-2003-0094 | |
| Download: ML031110190 (5) | |
Text
'r I
f- -i6t MEMORANDUM TO:
Joseph J. Holonich, Deputy Director Division of Incident Response Operations Office of Nuclear Security and Incident Response FROM:
William D. Beckner, Program Director Operating Reactor Improvements Program Division of Regulatory Improvement Programs Office of Nuclear Reactor Regulation INES Level Point Beach Event
SUBJECT:
This memorandum transmits the Event Rating Form (ERF) for an event which occurred at the Point Beach Nuclear Facility. The event was rated as an International Nuclear Event Scale (INES) Level 2.
Attachment:
Event Review Form (ERF) cc w/attachment:
T. Reis -
W. Beckner D. Matthews R. Borchardt J. Holonich CONTACT:
J. Dozier NRR/DRIP/RORP/OES 301-415-1014 Information in this record was deleted in accordance withthe Freedom of Informatfon Act. exenptio8 D
FOIA )
B 1
]
- See previous concurrence DOCUMENT NAME: G:\\RORP\\OES\\StaffFolders\\Dozier\\lnespointbeachdraft.wpd OFFICE RSE:OES:RORP SC:OES:RORP RA:RIII PD:RORP D:DRIP AD:ADIP NAME JDozier TReis JDyer WDBeckner DBMatthews RWBorchardt DATE 07/
/2002 07/11/2002 07/
/2002 07/11/2002 07/
/2002 07/
/2002
EVENT RATING FORM (ERF)
THE INTERNATIONAL NUCLEAR EVENT SCALE (INES)
EVENT TITLE EVENT DATE Potential Common Cause Failure of Auxiliary Feedwater 2001.11.29 RATING RATING OUT OF DEVIATION INCIDENT ACCIDENT FACILITY TYPE PROVISIONAL DATE SCALE 0
1 2 3
4 5
6 7 Power Reactor Research D FINAL D 2002.07.1 0
0 0 O 0 0 Radwaste Facility 0 Radiation Source a 0
COUNTRY FACILITY NAME Irradiation D Transportation Q
United States of America Point Beach, Nuclear Management Fuel Fabrication 0 Fuel 0
Co., United States of America Reprocessing LOCATION Research Facility Q Mining/Milling Dj Two Rivers, Wisconsin Enrichment D Other 0
Facility OFF-SITE IMPACT YES NO RELEASE BEYOND AUTHORIZED LIMITS 1
OVEREXPOSURE OF MEMBERS OF PUBLIC a
ON-SITE IMPACT CONTAMINATION SPREAD 0
N WORKER OVEREXPOSURE DAMAGE TO RADIOLOGICAL BARRIERS O
DEGRADATION OF DEFENCE IN-DEPTH PERSON INJURED PHYSICALLY OR CASUALTY IS THERE A CONTINUING PROBLEM PRESS RELEASE ISSUED (IF YES, PLEASE ATTACH)
EVENT DESCRIPTION On November 29, 2001, the licensee identified a potential common mode failure of the auxiliary feedwater (AFW) system upon a loss of instrument air. Specifically, a loss of instrument air woulc cause the AFW minimum flow recirculation valves to fail closed. At the time, there were no backup air or nitrogen accumulators associated with these specific valves. If the discharge or flow contro valves for the AFW pumps had been throttled or closed while the minimum flow recirculation valves were also closed, the AFW pumps would have been placed in a condition of insufficient flow. This could have resulted in pump damage in a short interval of time. The licensee also identified thai early in the post reactor trip emergency operating procedures, the operators were directed to control the AFW system flow without specific written guidance to maintain minimum AFW flow. The plant operators were directed to control flow to the steam generators to maintain desired level and to prevent overcooling of the reactor coolant system. The AFW minimum flow recirculation valves are air-operated valves. Without the short-term recovery of instrument air (within less than 10 minutes),
the AFW minimum flow recirculation valves would fail closed potentially damaging the AFW pumps and causing the loss of secondary heat removal capability. Heat removal capability through primary
system feed and bleed would also be adversely affected since instrument air is required to operate the pressurizer power-operated relief valves and nitrogen backup was not available. A loss of instrument air would cause a loss of normal feedwater and would initiate a dual-unit reactor trip.
In addition, other initiating events, e.g., fire, loss of off-site power, may have a similar vulnerability.
The licensee's corrective actions included prompt operator training, procedural changes to the emergencyoperating procedures, and the addition of back-up pneumaticsupplies fortheAFW pump minimum flow recirculation valves.
RATING JUSTIFICATION AND DIFFICULTIES ENCOUNTERED This event was rated in accordance with the INES User's Manual (2001) Edition. There were no off-site or on-site releases or consequences in this event. Also, no actual initiating events occurred. To obtain the INES rating, section IV-3.2.1.3 (b) "Events without a real initiator" of the INES Users Manual was used. The initiating event was assumed to be a loss of instrument air (LOIA). LOIA causes a loss of secondary cooling capability if all afw pumps are damaged due to insufficient flow.
Using Table IV of the INES User's manual, the operability of the degraded safety function (core cooling) was considered Adequate (C) because there are diverse means for reactor core cooling.
The generic frequency of the initiating event (LOIA) for the industry is 1 E-2, thus it has an "expected" frequency. Therefore, the event rating for impact on defense in depth without an actual initiator is INES Level 2.
CONTACT PERSON FOR FURTHER INFORMATION NAME
[erry Dozier IAFFILIATION lUS Nuclear Regulatory Commission ADDRESS PHONE I (301) 415-1014 FAX l
(301) 415-1032 E-MAIL [jxd@nrc.gov TO BE SENT TO THE IAEA INES COORDINATOR
- FAX: + 43 1 2600 29723 IAEA.WAGRAMERSTRASSE 5, P.O. BOX, 100 A-1400 VIENNA, AUSTRIA
- E-MAIL: D. Delatre@IAEA ORG Or D.RUAlTI@IAEA.ORG
. PHONE: + 43 1 2600 26068 or 26079 In addition, the following should be added to the Related Documents area for the event:
Full Text of Document:
A COPY OF THIS LETTER AND ITS ENCLOSURES IS AVAILABLE ELECTRONICALLY FOR PUBLIC INSPECTION IN THE NRC PUBLIC DOCUMENT ROOM OR FROM THE PUBLICLY AVAILABLE RECORDS (PARS) COMPONENT OF THE NRC'S DOCUMENT SYSTEM (ADAMS). ADAMS IS ACCESSIBLE FROM THE NRC WEB SITE AT http://www.nrc.aov/readinq-rm/adams.html (THE PUBLIC ELECTRONIC READING ROOM).
THE ADAMS ACCESSION NUMBER FOR THIS REPORT IS
DATE:
Division of Regulatory Improvement Programs COVER PAGE December 23, 2002
- ee ROUTING LIST ee*
NAME DATE
- 1. J. Dozier 07/
/02
- 2.
T. Reis 07/
/02
- 3.
W. Beckner 07/
/02
- 4.
J. Dyer 07/
/02
- 5.
D. Matthews 07/
/02
- 6.
R. Borchardt 07/
/02
- 7.
W. Beckner (Signature) 07/
/02
- 8.
J. Dozier/E-mail to Holonich 07/
/02
-. 1-
-t t
DOCUMENT NAME: G:\\RORP\\OES\\StaffFolders\\Dozier\\PointBeachl NES rpd ADAMS ACCESSION NUMBER: ML DATE ENTERED:
/
/02 FORM 665 ATTACHED and filled out:
YES NO