05000530/LER-2006-001, Regarding Two Independent Trains of Auxiliary Feedwater Inoperable

Regarding Two Independent Trains of Auxiliary Feedwater Inoperable

ML061150353
Person / Time
Site:	Palo Verde
Issue date:	04/18/2006
From:	Eubanks C Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-05463-CE/SAB/JAP/DFH LER 06-001-00
Download: ML061150353 (6)

LER-2006-001, Regarding Two Independent Trains of Auxiliary Feedwater Inoperable

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 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)(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 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability
5302006001R00 - NRC Website

text

i 10 CFR 50.73 I

A subsidiary of Pinnacle West Capital Corporation Palo Verde Nuclear Generatilg Station Cliff Eubanks Vice President Nuclear Operations Tel (623) 393.6116 Fax (623) 393-6077 Mail Station 7602 PO Box 52034 Phoenix, Arizona 85072-2034 102-05463-CE/SAB/JAP/DFH April 18, 2006 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

Dear sirs:

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Unit 3 Docket No. STN 50-530 License No. NPF 74 Licensee Event Report 2006-001-00 Attached please find Licensee Event Report (LER) 50-530/2006-001-00 prepared and submitted pursuant to 10 CFR 50.73. The LER reports two trains of Auxiliary Feed Water rendered inoperable as a result of a single watertight fire door being left operl and uncompensated.

In accordance with 10 CFR 50.73(d), 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 James A. Proctor, Section Leader, Regulatory Affairs, at (623) 393-5730.

The corrective actions described in this LER are not necessary to maintain compliance with regulations. Arizona Public Service Company makes no commitments in this letter.

Sincerely, A'Y~v CE/SABi/JAP/DFH/ca Attachment cc:

B. S. Mallett M. B. Fields G. G. Warnick NRC Region IV Regional Administrator NRC NRR Project Manager - (send electronic and paper)

NRC Senior Resident Inspector for PVNGS

'a--C
A

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 06/30/2007 (6.2004)

Estimated burden per response to comply with this mardatory 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 FOIAlPdvacy Service Brand'. (T-5 F52), U.S.

LICENSEE EVENT REPORT (LER)

Nuclear Regulatory Commission, 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-1 0202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to Impose an information (See reverse for required number of 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 digitstcharacters for each block)

Information collection.

. PAGE Palo Verde Nuclear Generating Station Unit 3 05000530 1 OF 5

4. TITLE Two Independent Trains of Auxiliary Feedwater Inoperable

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED_

SEUNILRVFACILITY NAME DOCK(ET NUMBER MONTH DAY YEAR YEAR S

EQUENTAL REV MONTH DAY YEAR None (15000

__0_2_(b)FACILITY NAME DOC (ET NUMBER 02 17 2006 2006 - 001 - 00 04 18 2006 None (05000

9. OPERATING MODE

1. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Checrkal bat apply) 0 20.2201(b)

El 20.2203(a)(3)(i) 0l 50.73(a)(2)(i)(C)

ED 50.73(a)(2I(vii) 1 0 20.2201(d) 0 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(A) 0 50.73(a)(2l(viii)(A) 0 20.2203(a)(1) 0 20.2203(a)(4) 0 50.73(a)(2)(ii)(B) 0 50.73(a)(21(viii)(B) 0l 20.2203(a)(2)(i) 0 50.36(c)(1)(i)(A) 0l 50.73(a)(2)(iii) 0 50.73(a)(2)(ix)(A)

10. POWER LEVEL.

E 20.2203(a)(2)(ii) 0 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(iv)(A) 0 50.73(a)(21(x) o 20.2203(a)(2)(iii) 0 50.36(c)(2) 0 50.73(a)(2)(v)(A) 0 73.71(a)(41 00 20.2203(a)(2)(iv) 0 50.46(a)(3)(ii) 0 50.73(a)(2)(v)(B) 0 73.71(a)(51 100 0

20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A) 0 50.73(a)(2)(v)(C) 0l OTHER 0 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B) 0 50.73(a)(2)(v)(D)

Specify in Abstract below or In (II more space is required, use additional copies of NRC Forn 366A)

1.

REPORTING REQUIREMENT(S)

This LER (50-530/2006-001-00) is being submitted pursuant to 10 CFR 50.73(a)(2)(vii),

to report an event where a single condition caused two independent trains to become inoperable in a single system designed to remove residual heat and mitigate the consequences of an accident. Specifically, on February 17, 2006 a watertight fire door (EIIS: NM, DR) functioning as the train separation barrier between Auxiliary Feedwaler (AFW) (EIIS: BA) pump rooms "A" and "B" was left open and unattended for4 minutes.

As a result, AFW trains "A" and "B" were rendered inoperable.

2.

DESCRIPTION OF STRUCTURE(S), SYSTEM(S) AND COMPONENT(S):

The AFW system consists of one essential steam turbine driven pump (train "A") (EIIS:

BA, P, TRB), one essential motor driven AFW pump (train "B") (EIIS: BA, P, MO), and one non-essential motor driven AFW pump (train "N") configured into three trains. TIhe essential steam turbine-driven and motor-driven AFW pumps are located on the 80 ft level in the Main Steam Support Structure (EIIS: NM) in separate rooms designed to seismic category I requirements. Each essential pump provides 100 percent of AFW flow capacity to the steam generators (EIIS: AB, SG) as assumed in the accident analysis. The AFW system mitigates the consequences of any event with a loss of normal feedwater (EIIS: SJ). The design basis of the essential AFW trains is to supply water to the steam generator to remove decay heat and other residual heat, by delivering at least the minimum required flow rate to the steam generators at pressures corresponding to 1270 psia at the entrance to the steam generators. A watertight fire door (C-A06) functions as the train separation barrier between train 'A' and 'B' AF pump rooms.

3.

INITIAL PLANT CONDITIONS

On February 17, 2006 at approximately 13:03 MST Palo Verde Unit 3 was in Mode l (power operations), operating at approximately 100 percent power. There were no major structures, systems, or components inoperable at the start of the event that contributed to the event.

NRCu (II 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)

• A procedure stand-down will be conducted to elevate the awareness of plant workers regarding the requirements to keep doors closed.

• Appropriate procedures will be revised to incorporate planning and coordination of the test process and to enhance prejob briefings when doors are required to remain open.

• Requirements for leaving doors open will be enhanced in the Palo Verde Site Access Training.

• Local door alarms will be installed with flashing lights to alert personnel that door C-A06 is open.

• Other doors with similar applicability will be evaluated to determine if a similar alarm feature is needed.

8.

PREVIOUS SIMILAR EVENTS

In the past three years, one similar event was reported as noted above (LER 50-529/2005-003-00).