05000298/LER-2007-005, Inadequate Post Fire Procedure Could Have Prevented Achieving Safe Shutdown
| ML072270071 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 08/08/2007 |
| From: | Michael Colomb Nebraska Public Power District (NPPD) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NLS2007057 LER 07-005-00 | |
| Download: ML072270071 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| 2982007005R00 - NRC Website | |
text
N Nebraska Public Power District Always there when you need us NLS2007057 August 8, 2007 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001
Subject:
Licensee Event Report No. 2007-005-00 Cooper Nuclear Station, Docket No. 50-298, DPR-46
Dear Sir or Madam:
The purpose of this correspondence is to forward Licensee Event Report 2007-005-00.
Sincerely, Michael J. Co nib General Manager of Plant Operations
/dm Enclosure cc:
Regional Administrator w/enclosure USNRC - Region IV Cooper Project Manager w/enclosure USN RC - NRR Project Directorate IV-I Senior Resident Inspector wv/enclosure USNRC - CNS SRAB Administrator wv/enclosure N PG Distribution w/enclosure INPO Records Center w/enclosure SORC Administrator wv/enclosure CNS Records w/enclosure COOPER NUCLEAR STATION P.O. Box 98 / Brownville, NE 68321-0098 Telephone: (402) 825-3811 / Fax: (402) 825-5211 www.nppd.com TV,-,
W10--
Abstract
On June 14, 2007, during validation of plant procedures associated with achieving safe shutdown during and after an Appendix R fire, Cooper Nuclear Station (CNS) determined there was no readily available success path to secure High Pressure Coolant Injection (HPCI) when required. Based on a conservative analysis and assumptions the postulated scenario involves a fire-induced spurious HPCI initiation that must be terminated within 10 minutes to prevent flooding main steam lines and disabling both Reactor Core Isolation Cooling and Automatic Depressurization System, each representing available strategies for achieving hot shutdown. As written, the post-fire procedure steps would not have been sufficient to isolate steam to the HPCI turbine.
CNS took immediate actions to revise procedures to provide adequate and effective validated instructions to isolate HPCI when required after a spurious initiation. This event was reported June 14, 2007 under 10 CFR 50.72(b)(3)(v)(A) by Emergency Notification Number 43421 as a condition that could have prevented the plant from achieving safe shutdown.
NRC FORM 366 (6-2004)
(If more space is required, use additional copies of (if more space is required, use additional copies of (If more space is required, use additional copies of Form 366A)
CAUSE
The process associated with preparation of Appendix R items within the Safe Shutdown Analysis Report (SSAR) lacked formal review.
Validations of the post-fire procedure were not fully effective because station practices concerning "don't open" type electrical enclosures prevented applicable procedure steps from being field verified as specified in the procedure change process.
CORRECTIVE ACTION
Immediate actions consisted of revising the procedures to provide adequate and effective validated instructions to isolate HPCI when required after a spurious initiation.
The following corrective actions are being tracked in the CNS corrective action program:
- 1)
Appendix R inputs to the SSAR shall be classified as Engineering Evaluations, and shall be subject to the same processes as Engineering Evaluations.
- 2)
Revise the procedure governing generation or revision of procedures to provide explicit, step-by-step guidance with respect to addressing validation of procedure steps that involve components inside "don't open" or otherwise inaccessible closures or cabinets.
PREVIOUS EVENTS There have been no reportable events identified in the past three years related to safe shutdown procedural deficiencies.
ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS©K)
ATTACHMENT 3 LIST OF REGULATORY COMMITMENTS© Correspondence Number: NLS2007057 The following table identifies those actions committed to by Nebraska Public Power District (NPPD) in this document. Any other actions discussed in the submittal represent intended or planned actions by NPPD. They are described for information only and are not regulatory
commitments
Please notify the Licensing Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments.
COMMITMENT
COMMITTED DATE
COMMITMENT
NUMBER OR OUTAGE None N/A N/A PROCEDURE 0.42 REVISION 22 PAGE 18 OF 25