ML103400085

LER Palo Verde, Unit 3 - Submittal of Special Report 3-SR-2010-001-00, Fuel Building Ventilation System High Range Radioactive Gaseous Effluent Monitor Inoperable

ML103400085
Person / Time
Site:	Palo Verde
Issue date:	11/22/2010
From:	Mims D Arizona Public Service Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
102-06283-DCM/KAC 3-SR-2010-001-00
Download: ML103400085 (4)

Text

ODCM 2.1 A P--- A subsidiaryof Pinnacle West CapitalCorporation 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 102-06283-DCM/KAC November 22, 2010 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Unit 3 Docket No. STN 50-530 License No. NPF-51 Special Report 3-SR-2010-001-00 Attached please find Special Report 3-SR-2010-001 -00, which is prepared and submitted pursuant to PVNGS Offsite Dose Calculation Manual (ODCM) requirements. This report discusses the inoperability of a fuel building ventilation system high range radioactive gaseous effluent monitor for more than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

By copy of this letter and the attachment, this report is being provided to the NRC Region IV Administrator and the PVNGS Resident Inspector.

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

Should you need further information regarding this submittal, please contact Marianne Webb, Compliance Section Leader, at (623) 393-5730.

Sincerely, DCM/MNW/KC/gat Enclosure Special Report 3-SR-2010-001-00, Fuel Building Ventilation System High Range Radioactive Gaseous Effluent Monitor Inoperable cc: (with enclosure)

E. E. Collins Jr. NRC Region IV Regional Administrator J. R. Hall NRC NRR Senior Project Manager L. K. Gibson NRC NRR Project Manager J. H. Bashore NRC Senior Resident Inspector (acting) for PVNGS A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway - Comanche Peak

• Diablo Canyon

• Palo Verde

• San Onofre - South Texas

• Wolf Creek AJAC

11-;

Enclosure Special Report 3-SR-2010-001-00 Fuel Building Ventilation System High Range Radioactive Gaseous Effluent Monitor Inoperable

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Palo Verde Nuclear Generating Station Special Report 3-SR-2010-001 -00 Fuel Building Ventilation System High Range Radioactive Gaseous Effluent Monitor Inoperable Docket No. STN 50-530, Unit 3 Reporting Requirement:

The PVNGS Offsite Dose Calculation Manual (ODCM) contains operability requirements for radioactive gaseous effluent monitoring instrumentation in Section 2.1, "Requirements: Gaseous Monitors." Action 42 for Table 2-1, Item 5, "Fuel Building Ventilation System," specifies that when the number of OPERABLE High Range Monitors is less than required by the Minimum Channels OPERABLE requirement, and the required monitor is not restored to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, then the associated actions are to:

a) Initiate the Preplanned Alternate Sampling Program to monitor the appropriate parameter(s) when it is needed.

b) Prepare and submit a Special Report to the Commission within 30 days following the event outlining the action(s) taken, the cause of the inoperability, and the plans and schedule for restoring the system to OPERABLE status.

Initial Conditions:

At 1405 Mountain Standard Time (MST) on October 21, 2010, Unit 3 was in a refueling outage, with the core off-loaded to the spent fuel pool. The fuel building ventilation system high range radioactive gaseous effluent monitor (RU-146) was declared inoperable due to its 120 VAC Class 1E power supply (PNB-D26) being removed from service.

RU-146 was not restored to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

Actions Taken:

The Preplanned Alternate Sampling Program was initiated pursuant to the ODCM Requirement 2.1, ACTION 42(a) on October 24, 2010, at 1405 MST. On October 28, 2010, at 0845 MST, RU-146 was declared OPERABLE after restoration of power and completion of the channel check surveillance test. There were no radiation level anomalies recorded during the compensatory period that alternate sampling was in place.

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Palo Verde Nuclear Generating Station Special Report 3-SR-2010-001-00 Cause of the Inoperability:

There was no monitor malfunction associated with the inoperability of RU-146. The cause for exceeding the 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> allowed by ODCM 2.1, Action 42(b), was primarily due to the voluntary implementation of a modification to improve the reliability of inverter (PNB-N12) during a time that imposed minimum risk impact to the station.

The inverter, the associated Class IE 125vdc bus, and therefore monitor RU-146, were specifically removed from service at a time when the reactor was defueled. This modification was scheduled to work 24/7 during a refueling outage because the scope of this work cannot be performed when the unit is operating. The cumulative effect of the work resulted in RU-1 46 being out of service for 162 hours0.00188 days <br />0.045 hours <br />2.678571e-4 weeks <br />6.1641e-5 months <br /> and 40 minutes.

Plans and Schedule for Restoring the Channels to OPERABLE Status:

On October 28, 2010, at 0845 MST, RU-1 46 was declared OPERABLE after completion of the channel check surveillance test.

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