05000354/LER-2009-006, Regarding Post-fire Safe Shutdown Analysis Error
| ML100490750 | |
| Person / Time | |
|---|---|
| Site: | Hope Creek  |
| Issue date: | 01/29/2010 |
| From: | Wagner L Public Service Enterprise Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| LR-N10-0024 LER 09-006-00 | |
| Download: ML100490750 (6) | |
| 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 |
| 3542009006R00 - NRC Website | |
text
PSEG Nuclear LLC P.O. Box 236, Hancocks Bridge, New Jersey 08038-0236 0 PSEG Nuclear LLC JAN 2 9 2010 LR-N10-0024 10CFR50.73 United States Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-001 Hope Creek Generating Station Unit 1 Facility Operating License No. NPF-57 Docket No. 50-354
Subject:
Licensee Event Report 2009-006 In accordance with 50.73(a)(2)(ii)(B), PSEG Nuclear LLC is submitting Licensee Event Report (LER) Number 2009-006.
Should you have any questions concerning this letter, please contact Mr. Timothy R. Devik at (856) 339-3108.
No regulatory commitments are contained in the LER.
Sincerely, Lawrence M. Wagner Plant Manager Hope Creek Generating Station Attachment: Licensee Event Report 2009-006 95-2168 REV. 7/99
.Page 2 LR-N 10-0024 Document Control Desk cc:
Mr. S. Collins, Administrator - Region 1 U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 Mr. R. Ennis, Project Manager Salemand Hope Creek U.S. Nuclear Regulatory Commission One White Flint North Mail Stop 08 BlA 11555 Rockville Pike-Rockville, MD 20852 USNRC Senior Resident Inspector - Hope Creek (X24)
P. Mulligan, Manager IV Bureau of Nuclear Engineering PO Box 415 Trenton, NJ 08625 Hope Creek Commitment Tracking Coordinator
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 8/31/2010 (9-2007)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the digits/characters for each block) information collection.
- 3. PAGE Hope Creek Generating Station 05000354 1 OF4
- 4. TITLE Post-fire Safe Shutdown Analysis Error
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED i
EUNILRVFACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR SUE R
MONTH DAY YEAR N/A NUMBER NO.N/
FACILITY NAME DOCKET NUMBER 12 02 2009 2009 - 006 - 000 01 29 2010 N/A
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply)
El 20.2201(b),
El 20.2203(a)(3)(i)
-] 50.73(a)(2)(i)(C)
El 50.73(a)(2)(vii) 1 El 20:2201(d)
'20.2203(a)(3)(ii)
El 50.73(a)(2)(ii)(A)
[I 50.73(a)(2)(viii)(A)
El 20.2203(a)(1)
[
20.2203(a)(4) 0 50.73(a)(2)(ii)(B)
-] 50.73(a)(2)(viii)(B)
-] 20.2203(a)(2)(i)
E. l 50.36(c)(1)(i)(A)
El 50.73(a)(2)(iii)
[I 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL
-] 20.2203(a),(2)(ii)
El 50.36(c)(1)(ii)(A)
[I 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x)
El 20.2203(a)(2)(iii)
El 50.36(c)(2)
El 50.73(a)(2)(v)(A)
El 73.71(a)(4)
El 20.2203(a)(2)(iv)
[I 50.46(a)(3)(ii) 0l 50.73(a)(2)(v)(B)
El 73.71(a)(5) 100 El 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A)
.[I 50.73(a)(2)(v)(C)
El OTHER El 20.2203(a)(2)(vi)
El 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in
SAFETY CONSEQUENCES AND IMPLICATIONS
The post-fire safe shutdown analysis (as described in UFSAR Section 9A and Tables 9A-8 and 9A-9) was incorrect in that the redundant HVAC fan would not be available to provide cooling to the non-fire area.
This is because the analysis did not recognize that the loss of the HVAC fans in the affected area would also prevent both of the chilled water pumps from operating, which in turn would cause the loss of the associated fans in several HVAC systems.
The loss of the chilled water pumps would have prevented the Control Room Emergency Filtration Systems from operating,.the plant would be in a TS required shutdown condition (TS 3.0.3) if one of the systems could not be returned to service.
The plant response would have been a loss of multiple HVAC systems, causing the operators to enter the Loss of HVAC abnormal procedure. The actions taken would be to open area doors and provide supplemental cooling fans. If the actions taken were not successful in maintaining temperatures, or if the control room crew determined that the conditions existed that necessitated evacuation of the control room (due to temperature or equipment mal-operation), the plant would have been shutdown from the remote shutdown panel (RSP). The remote shutdown procedure would have directed that the Division 11 chilled water pump be controlled from the RSP. Upon taking control of the chilled water pump at the RSP, the logic circuit (lowflow.interlock) preventing the chilled water pump operation would be bypassed and the chilled water pump could be started and the Division II HVAC systems could be reestablished for the affected areas. The use of the abnormal procedures is not credited in the post-fire safe shutdown analysis.
If the fire was located in the Division II area, the same actions would have been performed. The exception would be that once the Division II chilled water pump was started from the RSP, the Division I SACS room (in RB1) would not receive cooling because the Division I chilled water pump would still be prevented from operation due to the logic interrelationship with its affected fan in RB2. The effect would be that the Division II areas outside of RB2 would have HVAC supplies and the associated post-fire safe shutdown systems would be cooled, however the SACS Division I room would not have HVAC cooling. Division II is the only division that has RSP controls available, thus the Division I chilled water pump cannot be started from the RSP.
The fire would have been detected by the control room, due to multiple alarms and indications, and the loss of the chilled water pumps and associated HVAC systems would also be indicated in the control room.
A review of this event determined that a Safety System Functional Failure (SSFF) did not occur as defined in Nuclear Energy Institute (NEI) 99-02.
CAUSE OF OCCURRENCE The system interrelationships of the logic interlocks for the HVAC fans and the chilled water pumps was not properly understood in the initial post-fire safe shutdown analysis. The original analysis was based on commitments to GDC 3 of Appendix A to 10 CFR 50 and Branch Technical Position (BTP) Chemical Engineering Branch (CMEB) 9.5-1.
The post-fire safe shutdown analysis for fire areas RB1 and RB2 in the Hope Creek UFSAR, Table 9A-8 and Table 9A-9, states that the redundant HVAC fan located in the non-fire affected area will provide redundant cooling to that area. However, through the logic interlocks associated with the fans, the chilled water pumps will trip, and be prevented from running, removing HVAC systems from the SACS room, Control Equipment Room, Switchgear Room and Control Room. Loss of the chilled water pumps will prevent the associated HVAC fans from operating.
PREVIOUS OCCURRENCES
A review of Licensee Event Reports for the three prior years at Hope Creek was performed to determine if a similar event had occurred. No similar eventswere noted.
CORRECTIVE ACTIONS
The following corrective actions have been either taken or identified for this event:
(1) A fire watch was established until permanent corrective actions could be implemented.
(2) The fire response procedures for RB1 and RB2 have been revised to have an operator open the power supply (breaker) for the non-affected Division's fan located in the fire area to. de-energize the interlock and start the redundant chilled water pump.
(3) The post-fire safe shutdown analysis described in the UFSAR Tables T9A-8 and T9A-9 will be revised to take credit for the manual actions described in the procedures.
(4) An extent of condition review was performed. Other areas that have similar logic relationships have an analyzed post fire safe shutdown analysis that assumes operation at the remote shutdown panel (RSP). Operation of the systems at the RSP will bypass any interlock preventing system operation and allow a manual start of the affected systems. No revisions to the post-fire safe shutdown analysis were necessary for these areas.
(5) HC is reconstituting the post-fire safe shutdown analysis for the remaining fire areas.
COMMITMENTS
This LER contains no commitments.PRINTED ON RECYCLED PAPER