BSEP 09-0022, Special Report - Technical Requirements Manual Section 3.4, Accident Monitoring Instrumentation

Special Report - Technical Requirements Manual Section 3.4, Accident Monitoring Instrumentation

ML090690688
Person / Time
Site:	Brunswick
Issue date:	02/23/2009
From:	Mentel P Progress Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
BSEP 09-0022
Download: ML090690688 (3)

Text

Progress Energy February 23, 2009 SERIAL: BSEP 09-0022 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

Subject:

Brunswick Steam Electric Plant, Unit No. 2 Docket No. 50-324/License No. DPR-62 Special Report - Technical Requirements Manual Section 3.4, Accident Monitoring Instrumentation Ladies and Gentlemen:

In accordance with Technical Requirements Manual Section 3.4, "Accident Monitoring Instrumentation," for the Brunswick Steam Electric Plant (BSEP), Unit No. 2, Carolina Power & Light Company, now doing business as Progress Energy Carolinas, Inc., is submitting the enclosed Special Report associated with the Unit 2 Safety/Relief Valve Position Indication.

No regulatory commitments are contained in this letter. Please refer any questions regarding this submittal to Mr. Gene Atkinson, Supervisor - Licensing/Regulatory Programs, at (910) 457-2056.

Sincerely, Phyllis N. Mentel Manager - Support Services Brunswick Steam Electric Plant MAT/mat

Enclosure:

Special Report - Unit 2 Safety/Relief Valve Position Indication Progress Energy Carolinas, Inc.

Brunswick Nuclear Plant PO Box 10429 Southport, NC 28461

Document Control Desk BSEP 09-0022 / Page 2 cc (with enclosure):

U. S. Nuclear Regulatory Commission, Region II ATTN: Mr. Luis A. Reyes, Regional Administrator Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW, Suite 23T85 Atlanta, GA 30303-8931 U. S. Nuclear Regulatory Commission ATTN: Mr. Philip B. O'Bryan, NRC Senior Resident Inspector 8470 River Road Southport, NC 28461-8869 U. S. Nuclear Regulatory Commission (Electronic Copy Only)

ATTN: Mrs. Farideh E. Saba (Mail Stop OWFN 8G9A) 11555 Rockville Pike Rockville, MD 20852-2738 Chair -North Carolina Utilities Commission P.O. Box 29510 Raleigh, NC 27626-0510

BSEP 09-0022 Enclosure Page 1 of I Special Report - Unit 2 Safety/Relief Valve Position Indication

Background

On January 10, 2009, one channel of the Brunswick Steam Electric Plant (BSEP), Unit No. 2 Safety/Relief Valve Position Indication, Secondary-Temperature (i.e., Function 3.b. of Technical Requirements Manual (TRM) Table 3.4-1, "Accident Monitoring Instrumentation") was declared inoperable due to cycling of the tailpipe temperature indication (i.e., temperature element 2-B21-TE-NO04L) for Safety/Relief Valve (SRV) 2-B2 I-FO13L. As a result, Condition A of TRM Section 3.4, "Accident Monitoring Instrumentation," was entered, which required the position indication to be restored to operable status within 31 days. Repair of temperature element 2-B21-TE-NO04L cannot be completed with the unit online and, as a result, Condition C of TRM Section 3.4 was entered on February 10, 2009. This Special Report is submitted in accordance with Condition C of TRM Section 3.4.

Cause of Inoperability On January 10, 2009, temperature element 2-B21-TE-NO04L appeared to be failing and was declared inoperable when indicated Safety/Relief Valve tailpipe temperature was observed to be cycling between 185 degrees F and 195 degrees F. Between January 10, 2009, and January 23, 2009, a reduction in nominal indicated temperature was also observed which did not correspond to power reductions or drywell temperature changes. Since January 23, 2009, the cycling has dampened and the temperature element indicated nominal value has returned to its pre-January 10, 2009, level.

The temperature element is located inside the Unit 2 drywell. Further troubleshooting of the element is scheduled for the Unit 2 refueling outage (i.e., B219R1), currently scheduled to begin on February 28, 2009. The cause of the erratic temperature element cannot be conclusively determined until the troubleshooting activities are completed. However, based on investigation efforts completed to date, the degraded condition is most likely a result of a degraded connection within the cabling inside primary containment or a degraded component internal to the temperature element. As such, the repair of temperature element 2-B21-TE-NO04L cannot be completed with Unit 2 online. Required repairs will be completed during the upcoming B219R1 refueling outage.

Preplanned Alternate Monitoring Method During the time period that the 2-B21-TE-NO04L is inoperable, the redundant Primary-Sonic Safety/Relief Valve Position Indication (i.e., Function 3.a. of TRM Table 3.4-1) instrumentation provides monitoring capability. Additionally, although inoperable, SRV L tailpipe temperature indication remains available using 2-B2 1-TE-NO04L.

Plans for Restoring the Instrumentation Any required repairs of temperature element 2-B2 1 -TE-NO04L will be completed during the B219R1 refueling outage.