05000366/LER-2008-001, Regarding Leak in Vent Pipe to Process Pipe Sockolet in RHRSW System

Regarding Leak in Vent Pipe to Process Pipe Sockolet in RHRSW System

ML081120106
Person / Time
Site:	Hatch
Issue date:	04/18/2008
From:	Madison D Southern Nuclear Operating Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
NL-08-0622 LER 08-001-00
Download: ML081120106 (6)

LER-2008-001, Regarding Leak in Vent Pipe to Process Pipe Sockolet in RHRSW System

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(v), Loss of Safety Function 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)(ii)(B), Unanalyzed Condition 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)(i)(B), Prohibited by Technical Specifications
3662008001R00 - NRC Website

text

D. R......... (D....is)

VICe President* Hatch SoIdIIIID Nllc:lur 0...... e-pny, hlc.

Plant Edwin I. Hatch 11028 Hatch Parkway, North Baxley, Georgia 31513 1eI912.537.5859 Fax 912.366.20n SOUTHERN'\\'

COMPANY Erie,." to Se",e rollrWorld" April 18, 2008 Docket No.:

50-366 NL-08-0622 U. S. Nuclear Regulatory Commission ATIN: Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant - Unit 2 Licensee Event Report 2-2008-001 Leak in Vent Pipe to Process Pipe Sockolet in RHRSW System Ladies and Gentlemen:

In accordance with the requirements of 10 CFR 50.73 (a)(2)(v), Southern Nuclear Operating Company (SNC) is submitting the enclosed Licensee Event Report concerning a leak in a vent pipe sockolet attached to the Residual Heat Removal Service Water (RHRSW) system. A Supplemental Report will be submitted by May 16, 2008 regarding this event.

This letter contains no NRC commitments. If you have any questions, please advise.

Sincerely,

""~ ~~~.

D. R. Madison Vice President - Hatch DRMlRDBldaj Enclosure: LER 2-2008-001 cc: Southern Nuclear Operating Company Mr. J. T. Gasser, Executive Vice President Mr. D. R. Madison, Vice President - Hatch Mr. D. H. Jones, Vice President - Engineering RTYPE: CHA02.004 U. S. Nuclear RegUlatory Commissjon Mr. V. M. McCree, Acting Regional Administrator Mr. R. E. Martin, NRR Project Manager - Hatch Mr. J. A. Hickey, Senior Resident Inspector - Hatch

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (9-2007)

LICENSEE EVENT REPORT (LER)

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2010

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

1. FACILITY NAME Edwin I. Hatch Nuclear Plant-Unit 2

2. DOCKET NUMBER 05000 366

3. PAGE 1 OF 5

4. TITLE Leak in Vent Pipe to Process Pipe Sockolet in RHRSW System

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL NUMBER REV NO.

MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 05000 02 18 2008 2008 - 001 - 00 04 18 2008 FACILITY NAME DOCKET NUMBER 05000

9. OPERATING MODE 1

10. POWER LEVEL 100

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply) 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(i)(C) 50.73(a)(2)(vii) 20.2201(d) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2203(a)(1) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A) 20.2203(a)(2)(ii) 50.36(c)(1)(ii)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x) 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 50.73(a)(2)(v)(B) 73.71(a)(5) 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(C)

OTHER 20.2203(a)(2)(vi) 50.73(a)(2)(i)(B) 50.73(a)(2)(v)(D)

Specify in Abstract below or in (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 NRC Form 366A) PRINTED ON RECYCLED PAPER)

Previous Similar Events

LER 2-1999-006 included the complete failure of a 3/4 inch vent line near the weld where it joined the RHRSW system process piping. This vent line contained vent valve 2E11-FV003 which is the RHR A heat exchanger outlet vent valve.

The cause for the line failure was determined to be high cycle fatigue that was exacerbated by pipe geometry. Corrective actions included visual inspections of RHR, RHRSW and HPCI socket welds on both units with no crack like indications identified in December 2000. Vibration screening was performed for socket welds on RHR and RHRSW on both units with no problems identified with welds on the Unit 2 RHRSW system. Broadness actions taken for small bore piping on certain safety systems susceptible to similar high cycle fatigue were incomplete and too narrow. The root cause analyses were insufficient in determining the actual causes of the high cycle fatigue failures. Corrective actions for these issues are being addressed in the corrective action program.