05000482/LER-2005-005, Re Validation of Post Fire Safe Shutdown (PFSSD) Capabilities of Fire Area A-8
| ML053410148 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 11/28/2005 |
| From: | Hedges S Wolf Creek |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| FOIA/PA-2006-0095, WO 05-0033 LER 05-005-00 | |
| Download: ML053410148 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 4822005005R00 - NRC Website | |
text
W'&LF CREEK NUCLEAR OPERATING CORPORATION Stephen E. Hedges Vice President Operations and Plant Manager November 28, 2005
- - WO 05-0033 U. S. Nuclear Regulatory Commission I ATTN: Document Control Desk Washington, DC 20555
Subject:
Docket No. 50482: Licensee Event Report 2005-005-00 Gentlemen:
The enclosed Licensee Event Report (LER) 2005-005-00 is being submitted pursuant to 10 CFR 50.73(a)(2)(ii)(B) regarding an unanalyzed condition from a review of Post Fire Shutdown capabilities that could potentially affect post-fire safe shutdown equipment availability at Wolf Creek Generating Station.
Commitments made by Wolf Creek Nuclear Operating Corporation in the enclosed LER are identified in the Attachment to this letter.
If you have any questions concerning this matter, please contact me at (620) 3644190, or Mr.
Kevin Moles at (620) 3644126.
Very truly yours, E. Hedges SEH/rIg Attachment Enclosure cc:
J. N. Donohew (NRC), w/a, w/e W. B. Jones (NRC), w/a, w/e B. S. Mallett (NRC), w/a, w/e Senior Resident Inspector (NRC), w/a, w/e RPO. Box 411 / Burlington, KS 66839 / Phone: (620) 364-8831 An Equal Opportunity Employer M/F/HCNET
--T-
Attachment to WO 05-0033 Page 1 of 1 LIST OF COMMITMENTS The following table identifies those actions committed to by Wolf Creek Nuclear Operating Corporation in this document. Any other statements in this letter are provided for information purposes and are not considered regulatory commitments. Please direct questions regarding these commitments to Mr. Kevin Moles, Manager Regulatory Affairs at Wolf Creek Generating Station, (620) 364-4126.
REGULATORY COMMITMENT DUE DATE A detailed evaluation of fire area A-8 will be completed to 0112712006 identify any additional components that fail to meet the requirements of Appendix R.
Corrective measures resulting in a feasible post fire safe 07/21/2006 shutdown (PFSSD) methodology for a fire in fire area A-8 will be determined as needed.
For any corrective measures determined to be needed, a 05/30/2008 design change package will be developed and implemented.
a9 NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 06/30/2007 (6-2004)
, the NRC may (See reverse for required number of not conductor sponsor, and a person is not required to respond to, the digitslcharacters for each block) information collection.
- 3. PAGE WOLF CREEK GENERATING STATION 05000 482 1 OF 3
- 4. TITLE Validation of Post Fire Safe Shutdown (PFSSD) Capabilities of Fire Area A-8
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR ISEQUENTIAL REV MONTH DAY YEAR FACLiTYNAME 0
5 0
00 NUMBER NO.
I05000 FACILITY NAME DOCKET NUMBER 09 29 2005 2005 005 -
00 11 28 2005 05000
- 9. OPERATING MODE I1. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply) 1 5 20.2201(b) 5 20.2203(a)(3)(i) 5 50.73(a)(2)(i)(C)
[5] 50.73(a)(2)(vii) 5 20.2201(d) 5 20.2203(a)(3)(ii) 5 50.73(a)(2)(ii)(A) 5 50.73(a)(2)(viii)(A) 5 20.2203(a)(1) 5 20.2203(a)(4)
Ig1 50.73(a)(2)(ii)(B)
E] 50.73(a)(2)(viii)(B)
[_ 20.2203(a)(2)(i) 5J 50.36(c)(1)(i)(A) 5 50.73(a)(2)(iii) 5 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 5 20.2203(a)(2)(ii) 5 50.36(c)(1)(ii)(A) 5 50.73(a)(2)(iv)(A) 5 50.73(a)(2)(x) 10 20.2203(a)(2)(iii) 0 50.36(c)(2) 5 50.73(a)(2)(v)(A) 5 73.71 (a)(4) 100 E5 20.2203(a)(2)(iv) 5 50.46(a)(3)(Ii)
E5 50.73(a)(2)(v)(B)
E] 73.71 (a)(5) 5 20.2203(a)(2)(v) 5 50.73(a)(2)(i)(A) 5 50.73(a)(2)(v)(C) 5 OTHER a
20.2203(a)(2)(vi) 5 50.73(a)(2)(i)(B) 5 50.73(a)(2)(v)(D)
Specify In Abstract below
____or in (ff more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A)
Basis for Reportability:
A fire in Fire Area A-8 has the potential to damage the centrifugal charging pumps and cause a loss of the capability to borate the reactor. Based on this information, WCNOC made an eight hour Emergency Notification System call in accordance with 10 CFR 50.72(b)(3)(ii)(B).
This condition is also reportable pursuant to 10 CFR 50.73(a)(2)(ii)(B) for any event or condition that resulted in the nuclear power plant being in an unanalyzed condition that significantly degraded plant safety.
Root Cause:
This is a historical problem rooted in changes to the standards over time, and in non-validated assumptions made by the Architect-Engineer for their Electrical Fire Hazards Analysis at the time of construction and insufficiently documented at that time. Due to the historical nature of these facts, a specific root cause cannot be determined.
Corrective Actions
A detailed evaluation of fire area A-8 will be completed to identify any additional components that fail to meet WCGS commitments to Appendix R. Corrective measures will be determined as needed. Any necessary design change package(s) will be developed and implemented.
The current validation effort is currently being re-assessed to determine if any additional fire areas should be reviewed.
Safety Significance
This issue is of low safety significance due to the extreme conservative assumptions made for all of these failures to occur. There is a low loading of self-sustaining combustibles located in fire area A-8. A fire of the severity required to damage components and cables located over 80 feet apart is only postulated. The assumption that all of the spurious maloperations occur at time zero is also postulated since affected components and cables are located at various distances from one another. The reactor trip function will work correctly and the primary system can be isolated. The reported condition is outside Wolf Creek's licensing basis for protection of components required for safe shutdown following a fire since all mitigating actions may not be complete before damage occurs to the charging pumps.
Operating Experience/Previous Events:
LER 1999-009-00 determined an inadequate separation of cables for valves and level transmitters for the volume control tank. In the event of a fire, a potential existed for gas intrusion into the suction of the centrifugal charging pump. While corrective actions have been taken to address these conditions, an additional corrective action for LER 1999-009-00 was to validate the post fire safe shutdown analysis and to provide necessary correction to the Updated Safety Analysis Report (USAR). The validation consists of two phases: phase one reverified the design criteria and phase two completes the post-fire safe shutdown analysis review.
LERs 2002-004-00, 01, and 02 identified cable separation issues during the phase two portion of the validation process.