ML053040064

Special Report 2-SR-2005-003-00

ML053040064
Person / Time
Site:	Palo Verde
Issue date:	10/19/2005
From:	Eubanks C Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-05362-CE/DGM/DJS, 2-SR-2005-003-00
Download: ML053040064 (3)

Text

-

TS 3.3.10 (b)

LAPS A subsidiaryof Pinnacle Woest CapitolCorporation Cliff Eubanks Mail Station 7602 Palo Verde Nuclear Vice President Tel (623) 393-6116 PO Box 52034 Generating Station Nuclear Operations Fax (623) 393-6077 Phoenix. Arizona 85072-2034 102-05362-CE/DGM/DJS October 19, 2005 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, D.C. 20555-0001

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Unit 2 Docket No. STN 50-529 Special Report 2-SR-2005-003-00 Attached please find Special Report 2-SR-2005-003 prepared and submitted pursuant to the PVNGS Technical Specifications, section 3.3.10 (b), Required Action 6.1. This report discusses the inoperability of the Post Accident Sampling Instrumentation.

No commitments are being made to the NRC by this letter.

If you have questions regarding this request, please contact Daniel G. Marks, Section Leader, Regulatory Affairs, Compliance, at (623) 393-6492.

Sincerely, CE/DGM/DJS/ca

• cc: B. S. Mallet NRC Region IV Administrator (all w/attachment)

M. B. Fields NRC NRR Project Manager for PVNGS G. G. Warnick NRC Senior Resident Inspector for PVNGS c~ptal

Special Report No. 2-SR-2005-003-00 Palo Verde Nuclear Generating Station Unit 2 Post Accident Monitoring Instrumentation Inoperable Docket No. STN 50-529 Reporting Requirement:

The Palo Verde Nuclear Generating Station (PVNGS) Technical Specification (TS) section 3.3.10, Condition B, and 5.6.6 requires a report be submitted to the Nuclear Regulatory Commission if the Post Accident Monitoring (PAM) is inoperable for greater than thirty days. When a report is required by Condition B or G of LCO 3.3.10, "Post Accident Monitoring (PAM) Instrumentation," the report shall be submitted within the following 14 days. The report shall outline the preplanned alternate method of monitoring, the cause of the inoperability, and the plans and schedule for restoring the instrumentation channels of the Function to OPERABLE status.

Reactor Coolant System Activity Monitor 2JSQBRU01 51 (RU-1 51 radiation monitor) was declared inoperable by Operations on 9/10/2005 at 04:04.

Preplanned Alternate Method of Monitoring:

The Preplanned Alternate Method of Monitoring is addressed in Appendix A of site procedure "74RM-9EF43, Actions for Inoperable Radiation Monitors: Preplanned Alternate Sampling Program." Appendix A directs the station to use Emergency Plan Implementing Procedure (EPIP) -99 Appendix L - Accident Sampling as the alternate method of monitoring.

Appendix L includes the following alternate methods:

• Depressurized Liquid Sampling (RCS Hot Leg and Safety Injection/Shutdown Cooling)

• Containment Air Sampling

• RU-144 / RU-146 High Range sampling

Apparent Cause of the Inoperabilitv:

Reactor Coolant System Activity Monitor 2JSQBRU0151 (RU-151 radiation monitor)

Troubleshooting to date has isolated the failure of the RU-1 51 radiation monitor to the ion chamber detector. The detector was replaced under CMWO 2831862 on 10/14/05.

The apparent cause of this failure (to 2JSQBRU0151) is a failure of the Ion Chamber Detector to produce the proper amount of signal current commensurate with the radiation field. The detector is the lowest serviceable component within the radiation monitor. There were no environmental factors or other contributing causal factors determined to be evident.

(Note: The BASES section of TS says that the results of the root cause evaluation of inoperability is to be discussed. If the above apparent cause would alter a reviewer's perception of the event once the investigation has been completed, a supplement to this Special Report will be generated.)

Background:

At the time of the failure, Unit 2 was operating in Mode 1. The detector is physically located in the reactor coolant pump bay, in close proximity to the reactor coolant loops; it can not be worked on during power operation. The existing radiation levels are approximately 20 Rads per hour. Additionally, the work is to be performed adjacent to the RC piping and the high temperature environment dictates that the work be performed in Mode 5.

Plans and Schedule for restoring the system to OPERABLE status:

Schedule:

An unplanned outage commenced on October 11, 2005 where the plant was shut down and cooled down allowing conditions that facilitated the required repairs. The ion chamber was replaced on October 14, 2005 and the monitor was restored to operation at that time.