05000423/LER-2008-006, For Millstone, Unit 3, Regarding Turbine-Driven Auxiliary Feedwater Pump Steam Trap Isolation Valves Found Closed
| ML090430397 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 01/28/2009 |
| From: | Jordan A Dominion, Dominion Nuclear Connecticut |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 08-0787 LER 08-006-00 | |
| Download: ML090430397 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown |
| 4232008006R00 - NRC Website | |
text
4Dominion Dominion Nuclear Connecticut, Inc.
Millstone Power Station Rope Ferry Road, Waterford, CT 06385
'JAN 2 8 2009 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Serial No.
MPS Lic/MLC Docket No.
License No.
08-0787 RO 50-423 NPF-49 DOMINION NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNIT 3 LICENSEE EVENT REPORT 2008-006-00, TURBINE-DRIVEN AUXILIARY FEEDWATER PUMP STEAM TRAP ISOLATION VALVES FOUND CLOSED This letter forwards Licensee Event Report (LER) 2008-006-00, documenting a condition identified at Millstone Power Station Unit 3, on November 24, 2008. This LER is being submitted pursuant to 10 CFR 50.73(a)(2)(i)(B), as a condition prohibited by technical specifications.
If you have any questions or require additional information, please contact Mr. William D. Bartron at (860) 444-4301.
Sincerely, sA.J.
Jlrdan Site Vii VePresident - Millstone
Serial No. 08-0787 Licensee Event Report 2008-006-00 Page 2 of 2
Attachment:
1 Commitments made in this letter: None.
cc:
U.S. Nuclear Regulatory Commission Region I 475 Allendale Road King of Prussia, PA 19406-1415 Ms. C. J. Sanders - Project Manager U.S. Nuclear Regulatory Commission, Mail Stop 08 B3 One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738 NRC Senior Resident Inspector Millstone Power Station
Serial No. 08-0787 Attachment I Licensee Event Report 2008-006-00 TURBINE-DRIVEN AUXILIARY FEEDWATER PUMP STEAM TRAP ISOLATION VALVES FOUND CLOSED MILLSTONE POWER STATION UNIT 3 DOMINION NUCLEAR CONNECTICUT, INC.
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 08/31/2010 (9-2007)
Eshmated, the RC may not conduct or sponsor, and a person is not required to respond to, the onormaton collection.
(See reverse for required number of digits/characters for each block)
- 3. PAGE Millstone Power Station - Unit 3 05000423 1 OF 3
- 4. TITLE Turbine-Driven Auxiliary Feedwater Pump Steam Trap Isolation Valves Found Closed
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED FACILITY NAME DOCKET NUMBER
- - MO DAY YEAR YEAR SEQUENTIAL REV MO DAY YEAR NUMBER NO.
FACILITY NAME DOCKET NUMBER 11 24 2008 2008-006-00 01 28 2009
- 9. O11.
THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply,)
20.2201(b) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 018 20.2201(d) 20.2203(a)(4) 50.73(a)(2)(iii) 50.73(a)(2)(x) 20.2203(a)(1) 50.36(c)(1)(i)(A) 50.73(a)(2)(iv)(A) 73.71 (a)(4) 120.2203(a)(2)(i) 50.36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71 (a)(5) 20.2203(a)(2)(ii) 50.36(c)(2) 50.73(a)(2)(v)(B)
OTHER 20.2203(a)(2)(iii) 50.46(a)(3)(ii) 50.73(a)(2)(v)(C)
Specify in Abstract below or 20.2203(a)(2)(iv) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D) in (If more space is required, use additional copies of NRC Form 366A) (17)
- 3.
Assessment of Safety Consequences
This condition is judged to be of low safety significance. Although it is possible the TDAFW pump would have tripped on turbine overspeed when called upon to start, procedures and training provide guidance to operators to manually start the pump in the event of a pump trip. During the time the valves were closed, both motor-driven AFW pumps [BA-P] were operable. When the plant is operating at low power levels (post refuel), there is low decay heat and increased SG water inventory. Hence, if auto-initiation of the TDAFW pump had resulted in a pump trip, the low decay heat and increased SG water inventory would have provided sufficient time to restart the pump if operation was required. Therefore, the potential impact of a loss of normal feedwater flow at low power levels is minimized because of available response time.
4. Corrective Actions
Upon discovery of this condition, MPS3 entered TSAS 3.7.1.2.c. The steam trap isolation valves were promptly re-opened, the steam traps blown down, and the TDAFW pump restored to operable status.
The operating procedure for main turbine shell and chest warming has been revised to specify the TDAFW pump steam trap isolation valves will remain open during future shell and chest warming evolutions.
Additional corrective actions to address this event will be evaluated in accordance with the station's Corrective Action Program.
5. Previous Occurrences
None Energy Industry Identification System (EIIS) codes are identified in the text as [XX].