05000529/LER-2007-003, Manual Reactor Trip Due to Increased Steam Generator Sodium Levels from Failed Heat Exchanger Plug

Manual Reactor Trip Due to Increased Steam Generator Sodium Levels from Failed Heat Exchanger Plug

ML073480125
Person / Time
Site:	Palo Verde  (NPF-051)
Issue date:	12/05/2007
From:	Mims D Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-05777-DCM/REB LER 07-003-00
Download: ML073480125 (6)

LER-2007-003, Manual Reactor Trip Due to Increased Steam Generator Sodium Levels from Failed Heat Exchanger Plug

Event date:
Report date:
Reporting criterion:	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)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications
5292007003R00 - NRC Website

text

10 CFR 50.73 A subsidiary of Pinnacle West Capital Corporation Dwight C. Mims Mail Station 7605 Palo Verde Nuclear Vice President Tel. 623-393-5403 P.O. Box 52034 Generating Station Regulatory Affairs and Plant Improvement Fax 623-393-6077 Phoenix, Arizona 85072-2034 102-05777-DCM/REB December 05, 2007 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Dear Sirs:

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Unit 2 Docket No. STN 50-529 License No. NPF 51 Licensee Event Report 2007-003-00 Attached, please find Licensee Event Report (LER) 50-529/2007-003-00 which reports a manually initiated reactor trip from approximately 100 percent power due to elevated Steam Generator sodium levels.

In accordance with 10 CFR 50.4, copies of this LER are being forwarded to the NRC Regional Office, NRC Region IV and the Senior Resident Inspector. If you have questions regarding this submittal, please contact Ray E. Buzard, Section Leader, Regulatory Affairs, at (623) 393-5317.

Arizona Public Service Company makes no commitments in this letter..

Sincerely, DCM/REB/gat Attachment cc:

E. E. Collins Jr.

NRC Region IV Regional Administrator M. T. Markley NRC NRR Project Manager - (send electronic and paper)

G. G. Warnick NRC Senior Resident Inspector for PVNGS A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway

• Comanche Peak

• Diablo Canyon 9 Palo Verde South Texas Project

• Wolf Creek

I. 4"ý NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 06/30/2007 (6-2004)

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

I3 PAGE Palo Verde Nuclear Generating Station (PVNGS) Unit 2 05000529 1 OF 5

4. TITLE Manual Reactor Trip due to Increased Steam Generator Sodium Levels from Failed Heat Exchanger Plug

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

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

MONTH DAY YEAR None FACILITY NAME DOCKET NUMBER 10 06 2007 2007

- 003 -

00 12 05 2007 None

9. OPERATING MODE

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply)

[1 20.2201(b)

[I 20.2203(a)(3)(i)

[I 50.73(a)(2)(i)(C)

[I 50.73(a)(2)(vii)

E] 20.2201(d)

E] 20.2203(a)(3)(ii)

[1 50.73(a)(2)(ii)(A)

El 50.73(a)(2)(viii)(A)

El 20.2203(a)(1)

El 20.2203(a)(4)

El 50.73(a)(2)(ii)(B)

El 50.73(a)(2)(viii)(B)

El 20.2203(a)(2)(i)

El 50.36(c)(1)(i)(A)

El 50.73(a)(2)(iii)

[I 50.73(a)(2)(ix)(A)

10. POWER LEVEL EJ 20.2203(a)(2)(ii)

El 50.36(c)(1)(ii)(A)

Z 50.73(a)(2)(iv)(A)

El 50.73(a)(2)(x)

[I 20.2203(a)(2)(iii)

El 50.36(c)(2)

El 50.73(a)(2)(v)(A)

[1 73.71(a)(4)

[I 20.2203(a)(2)(iv)

El 50.46(a)(3)(ii)

El 50.73(a)(2)(v)(B)

El 73.71(a)(5) 100 El 20.2203(a)(2)(v)

[I 50.73(a)(2)(i)(A)

El 50.73(a)(2)(v)(C)

El OTHER El 20.2203(a)(2)(vi)

[E 50.73(a)(2)(i)(B)

E] 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 (If more space is required, use additional copies of NRC Form 366A)

8.

PREVIOUS SIMILAR EVENTS

LER 50-528/2003-002-01 reported a manually initiated reactor trip from approximately 97 percent power due to elevated Steam Generator sodium levels due to a failed tube plug in the main condenser. The failure mechanism for that plug was determined to be a manufacturing defect which was further aggravated during installation of the plug. Because the failure mechanism and type of plug was different, the corrective actions associated with that event would not have prevented this event.