05000338/LER-2007-001, Re Reactor Trip Due to Steam Generator Low Level Coincident with a Steam Flow Feed Flow Mismatch
| ML070650344 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 02/27/2007 |
| From: | Stoddard D Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, NRC/NRR/ADRO |
| References | |
| 07-0014 LER 07-001-00 | |
| Download: ML070650344 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 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 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(viii)(A) |
| 3382007001R00 - NRC Website | |
text
1 OCFR50.73 Virginia Electric and Power Company North Anna Power Station P. 0. Box 402 Mineral, Virginia 23117 February 27, 2007 U. S. Nuclear Regulatory Commission Serial No.:
07-0014 Attention: Document Control Desk NAPS:
MPW Washington, D. C. 20555-0001 Docket No.: 50-338 License No.: NPF-4
Dear Sirs:
Pursuant to 10CFR50.73, Virginia Electric and Power Company hereby submits the following Licensee Event Report applicable to North Anna Power Station Unit 1.
Report No. 50-338/2007-001-00 This report has been reviewed by the Station Nuclear Safety and Operating Committee and will be forwarded to the Management Safety Review Committee for its review.
Sincerely, Daniel G. Stoddard Site Vice President North Anna Power Station Enclosure Commitments contained in this letter: None cc:
United States Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, Georgia 30303-8931 Mr. J. T. Reece NRC Senior Resident Inspector North Anna Power Station
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 6-30-2007 (6-2004)
Estimated burden per response to comply with this mandatory collection request: 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />. Reported lessons learned are incorporated into the licensing process and fed back to industry. Send comments regarding burden estimate to the Records and FOIA/Privacy Service Branch (T-5 F52), U.S. Nuclear Regulatory Commission, LICENSEE EVENT REPORT (LER)
Washington, DC 20555-0001, or by internet e-mail to infocollects@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202 (3150-(See reverse for required number of digits/characters for each block) 0066), Office of Management and Budget, Washington, DC 20503. If a means used to impose information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE NORTH ANNA POWER STATION, UNIT 1 05000 338 1 OF 4
- 4. TITLE Reactor Trio Due To Steam Generator Low Level Coincident With A Steam Flow Feed Flow Mismatch
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL REVISION MONTH DAY YEAR FACILITY NAME DOCUMENT NUMBER M IAY Y
NUMBER NO MONT_
_AYR 05000 01 03 2007 2007
--001--
00 02 27 2007 FACILITY NAME DOCUMENT NUMBER 1
05000
- 9.
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
OPERATING MODE 1
20.2201(b) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)
- 10. POWER.
20.2201(d) 20.2203(a)(4) 50.73(a)(2)(iii) 50.73(a)(2)(x)
LEVEL 100%/
20.2203(a)(1) 50.36(c)(1)(i)(A)
X 50.73(a)(2)(iv)(A) 73.71(a)(4) 20.2203(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) 20.2203(a)(2)(iv) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D)
J 20.2203(a)(2)(v) 50.73(a)(2)(i)(B)
I 50.73(a)(2)(vii)
Specify in Abstract below or 20.2203(a)(2)(vi) 50.73(a)(2)(i)(C) 50.73(a)(2)(viii)(A) in (If more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A) (17)
7.0 SIMILAR EVENTS
LER N2-06-001 -00 dated 11/16/06, documents an automatic reactor trip from "B" steam generator low level coincident with a steam flow greater than feed flow mismatch caused by closure of the "B" MFRV. Closure of the "B" MFRV was the result of a failed isolator card in the SG water level control system for "B" SG. The isolator card failure was a result of one or more transistors in the power supply circuit of the card. The root cause of the transistor failure is age-related degradation.
LER N2-03-001-00 dated 03/31/03, documents an automatic reactor trip from "C" steam generator low level coincident with a steam flow greater than feed flow mismatch caused by closure of the "C" MFRV. Closure of the "C" MFRV was the result of a failed driver card in the SG water level control system for "C" SG. The driver card failed as a result of a blown fuse. The corrective actions from this event focused solely on the driver cards.
Fuses were inspected on both units with repairs made to several cards.
8.0 ADDITIONAL INFORMATION
At the time of this event Unit 2 was in Mode 1 operating at 100 percent power and was not affected by this event.
Component information:
Description
Process Control Type NCB Manufacturer:
Westinghouse Model No.:
2838A30G01 Serial No.:
918378