05000528/LER-2004-008, Regarding Improper Contact Configuration on Containment Isolation Valve

Regarding Improper Contact Configuration on Containment Isolation Valve

ML042660125
Person / Time
Site:	Palo Verde
Issue date:	09/15/2004
From:	Danni Smith Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
192-01153-DMS/SAB/DGM/DFH LER 04-008-00
Download: ML042660125 (6)

LER-2004-008, Regarding Improper Contact Configuration on Containment Isolation Valve

Event date:
Report date:
5282004008R00 - NRC Website

text

LAS

.4A sbhsidiary ofPinnacle lIst Capital Corporation Palo Verde Nuclear Generating Station David M. Smith Tel.

623-393-6116 Mail Station 7602 Plant Manager Fax.

623-393-6077 P.O. Box 52034 Nuclear Production e-mail: DSMITH10@apsc.com Phoenix. AZ 85072-2034 10 CFR 50.73 192-01153-DMS/SAB/DGM/DFH September 15, 2004 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

Dear Sirs:

Subject:

Palo Verde Nuclear Generating Station (PVNGS) Unit 1 Docket No. STN 50-528 License No. NPF-41 Licensee Event Report 2004-008-00 Attached, please find Licensee Event Report (LER) 50-528/2004-008-00 that has been prepared and submitted pursuant to 1 OCFR50.73. The LER reports a condition prohibited by Technical Specification (TS) 3.6.3, that resulted in the loss of the automatic closure function of a single containment isolation valve in a penetration flow path with two containment isolation valves.

In accordance with 10CFR50.4, a copy of this LER is being forwarded to the NRC Regional Office, NRC Region IV and the Resident Inspector. If you have questions regarding this submittal, please contact Daniel G. Marks, Section Leader, Regulatory Affairs, at (623) 393-6492.

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

Sincerely, DMS/SAB/DGM/DFH/kg Attachment cc:

B. S. Mallett NRC Region IV Administrator N. L. Salgado NRC Senior Resident Inspector for PVNGS M. B. Fields NRC NRR Project Manager

APPROVED BY OMB NO. 3150-0104 EXPIRES 7-31-2004

Abstract

On July 19, 2004, at approximately 16:18 Mountain Standard Time (MST), Unit 1 was in Mode 1 at 100 percent power, when troubleshooting identified a rotor cam, which actuates a bank of limit switches, on a containment isolation valve (IJHPBUVO004) out of position due to personnel error.

The rotor cam was oriented such that the limit switch in this bank would actuate opposite of the desired control logic for the Safety Equipment Actuation Status (SEAS) and Containment Isolation Actuation Signal (CIAS). With valve 1JHPBUVO04 in the open position, the valve's CIAS closing circuit was interrupted which would prevent the valve from closing upon a CIAS. The valve was declared inoperable and Unit 1 entered Limited Condition for Operation (LCO) 3.6.3 Condition A, (Containment Isolation) and LCO 3.6.7 Condition A (Hydrogen Recombiner B) and LCO 3.3.10 Condition A (Hydrogen Analyzer B). Valve 1JHPBUVO04 was returned to service and declared operable on July 23, 2004 (11:36 MST).

A similar event occurred after Unit 3's seventh refueling outage where the CIAS function of 3JHPAUV0001 was disabled due to an incorrect control wire configuration. The event is documented on LER 99-001-00.

NRC FORM 366 (7-2001)

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7.

CORRECTIVE ACTIONS

Contact configuration was corrected on July 23, 2004 (11:36 MST), and valve 1JHPBUVO004 was declared operable. Based on the preliminary results from the investigation the following corrective actions have been taken or are planned to prevent recurrence:

• PM Task will be changed to specify retest as required by 39DP-9ZZ04, uValve Service Maintenance - Motor Operated Valves", which requires the verification of the contact configuration and light indication with the valve stroke test.

• Training will include this event during the quarterly Industry Events for Maintenance Personnel.

• Operator Requalification Training will include this event during simulator cycle 5 training.

• Engineering will evaluate moving the contact function for SEAS and CIAS from rotor 1AS3 to 1AS6 to reduce the potential for configuration errors.

Any additional corrective actions taken as a result of the investigation of this event will be implemented in accordance with the APS corrective action program. If information is subsequently developed that would significantly affect a reader's understanding or perception of this event, a supplement to this LER will be submitted.

8. PREVIOUS SIMILAR EVENTS

A similar event occurred after Unit 3's seventh refueling outage where the CIAS function of 3JHPAUVO001 was disabled due to an incorrect control wire configuration. This event is documented on LER 99-001-00.

9. ADDITIONAL INFORMATION

None.