BSEP-98-0159, Requests NRC Concurrence W/Plans to Remove Piping Welds Outboard of Second Containment Isolation Valve in RWC Sys of Plant,From Insp Extent & Frequency Outlined in GL 88-01, NRC Position on IGSCC in BWR Austenitic Stainless..

Requests NRC Concurrence W/Plans to Remove Piping Welds Outboard of Second Containment Isolation Valve in RWC Sys of Plant,From Insp Extent & Frequency Outlined in GL 88-01, NRC Position on IGSCC in BWR Austenitic Stainless..

ML20237C891
Person / Time
Site:	Brunswick
Issue date:	08/20/1998
From:	Jury K CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
BSEP-98-0159, BSEP-98-159, GL-88-01, GL-88-1, NUDOCS 9808240228
Download: ML20237C891 (8)

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CP&L.

Carolina Power & Light Company l , P.o. Box 10429

Southport, NC 28461 0429 l

! AUG 2 01998 i r i SERIAL: BSEP 98-0159 U. S. Nuclear Regulatory Commission  !

ATTN: Document Control Desk Washington, DC 20555-0001 l BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS.1 AND 2 DOCKET NOS. 50-325 AND 50-324/ LICENSE NOS. DPR-71 AND DPR-62 INTERGRANULAR STRESS CORROSION CRACKING INSPECTION PLAN FOR j F

' REACTOR WATER CLEANUP SYSTEM PIPING WELDS OUTBOARD OF TIIE SECOND CONTAINMENT ISOLATION VALVE  !

Gentlemen:

The purpose of this letter is to request NRC concurrence with Carolina Power & Light (CP&L)

Company's plans' to remove the piping welds outboard of the second containment isolation valve in the Reactor Weter Cleanup systems, of the Brunswick Steam Electric Plant (BSEP), Unit Nos. I and 2, from the inspection extent and frequency outlined in NRC Generic Letter 88-01, "NRC Position On IGSCC In BWR Austenitic Stainless Steel Piping." The removal of these l welds is based on criteria previously used by the NRC to review and approve a similar request l for the Limerick Generating Station.

l L ' Enclosure 1 provides the basis for this request. A list of regulatory commitments contained in this letter is provided in Enclosure 2.

l NRC approval of this request is needed by February 1,' 1999, in order to support planning l activities for the BSEP, Unit 2 Refueling Outage 13 (i.e., B214RI), which is scheduled to begin on April 17,1999.

Please refer any questions regarding this submittal to Mr. Warren J. Dorman, Supervisor -

Licensing, at (910) 457-2068.

l Sincerely, I

, D I Keith R. Jury

.. , Manager- Regulatory Affairs JJ Brunswick Steam Electric Plant 9808240228 980820 $

PDR ADOCK 05000324 b l l P PDR s  ;

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l Document Control Desk BSEP 98-0159'/ Page 2 WRM/wrm l

Enclosures:

l 1. Basis of Request l~

2. List of Regulatory Commitments cc (with enclosures):

U. S. Nuclear Regulatory Commission, Region II l ATTN: Mr. Luis A. Reyes, Regional Administrator Atlanta Federal Center 61 Forsyth Street, EVI, Suite 23T85 Atlanta, GA 30303 U. S. Nuclear Regulatory Commission ATTN: Mr. Charles A. Patterson, NRC Senior Resident Inspector 8470 River Road Southport, NC 28461-8869 t U. S. Nuclear Regulatory Commission i ATTN: Mr. David C. Trimble, Jr. (Mail Stop OWFN 14H22) 11555 Rockville Pike Rockville, MD 20852-2738 Ms. Jo A. Sanford Chair - North Carolina Utilities Commission P.O. Box 29510 Raleigh, NC 27626-0510 Division of Boiler and Pressure Vessel North Carolina Department of Labor ATTN: Mr. Jack Given, Assistant Director of Boiler & Pressure Vessels 4 West Edenton Street Raleigh, NC 27501-1092 l

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ENCLOSURE 1 BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS.1 AND 2 DOCKET NOS. 50-325 AND 50-324/ LICENSE NOS. DPR-71 AND DPR-62

INTERGRANULAR STRESS CORROSION CRACKING INSPECTION PLAN FOR REACTOR WATER CLEANUP SYSTEM PIPING WELDS OUTBOARD OF THE SECOND l

CONTAINMENT ISOLATION VALVE i

BASIS OF REOUEST

SUMMARY

The purpose of this letter is to request NRC concurrence with Carolina Power & I.ight (CP&L)  ;

Company's plans to remove the piping welds outboard of the second containment isolation valve l l - in the Reactor Water Cleanup (RWCU) systems, of the Brunswick Steam Electric Plant (BSEP),

i Unit Nos. I and 2, from the inspection extent and frequency outlined in NRC Generic i Letter 88-01,"NRC Position On IGSCC In BWR Austenitic Stainless Steel Piping. The removal of these welds is based on criteria previously used by the NRC to review and approve a similar i request for the Limerick Generating Station.

DISCUSSION: i On January 25,1988, the NRC issued Generic Letter 88-01; the technical bases for the NRC positions in Generic letter 88-01 were published in Revision 2 of NUREG-0313, " Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping." The scope of both NRC Generic Letter 88-01 and NUREG-0313 applied to boiling water reactor piping made of austenitic stainless steel that is four inches or larger in nominal diameter and contains reactor coolant at a temperature above 200 F during power operation, regardless of piping Code classification.

By letter dated July 18,1988 (Serial: NLS-88-160), CP&L agreed to follow the NRC staff position regarding the extent and frequency ofinspection for various categories of welds.

Susceptible piping welds in RWCU system outboard of the second containment isolation valve were included in this inspection scope.

Since Generic Letter 88-01 was issued, the NRC staff has established criteria for the c av and j acceptance of altemative inspection schedules applicable to the portion of the RWCU system L outboard of the second containment isolation valve. By letter dated June 21,1995, as i

supplemented by letter dated January 5,1996, Philadelphia Electric Company (PECO) requested approval to eliminate intergranular stress corrosion cracking (IGSCC) inspection (i.e., ultrasonic El-1

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testing)'of RWCU system piping welds outboard of the primary containment isolation valves at

the Limerick Generating Station. The NRC approved the PECO request in a letter dated i

February 7,1996 (Reference 1). To qualify for eliminating any augmented IGSCC inspections in the subject piping, the following conditions were required to be met:

1) The piping outboard of the second containment isolation valve be made of resistant i material, 1

l 2) Absence ofIGSCC indications in RWCU system piping welds inboard of the second ,

l isolation valves (on-going NRC Generic Letter 88-01 inspection), and i E

3) Absence ofIGSCC indications in RWCU system piping welds outboard of the second isolation valves after inspecting a minimum of 10 percent of the susceptible piping welds.

CP&L is requMing approval to eliminate from the inspection extent and frequency outlined in NRC Generi. .etter 88-01 the piping welds in the BSEP, Unit Nos. .I and 2, RWCU systems outboard of the second containment isolation valve. The following bases for the removal of these welds demonstrates that the previously used NRC acceptance criteria for eliminating the l augmented IGSCC inspections specified in Generic Letter 88-01 have been met. l Criterion 1: Piping Outboard of the Second Isolation Valve Is Made of Resistant Material l.

CP&L Basis:

By letter dated January 27,1989 (Serial: NLS-89-017), for BSEP Unit 1, and by letter dated February 21,1990 (Serial: NLS-90-036), for BSEP Unit 2, CP&L notified the NRC that the susceptible portions of the RWCU systems (i.e., outboard of the second containment isolation valve) have been rephed with a low carbon wrought austenitic stainless steel material (i.e.,

IGSCC resistant) in accordance with the recommendations outlined in NUREG-0313, L Revision 2.

Criterion 2: Absence ofIGSCC Indications In RWCU System Piping Welds Inboard of the Second Isolation Valves (On-going NRC Generic Letter 88-01 Inspection)

! CP&L Basis:

l The inspection extent and frequency of the susceptible RWCU system piping welds inboard of L the second containment isolation valve, as outlined in NRC Generic Letter 88-01, are being met.

- The inspection methods recommended in NUREG-0313, for detecting and evaluating IGSCC, are also being implemented for these welds. To date,6 of the 21 (i.e., approximately 28.6 percent) BSEP, Unit 1 RWCU system piping welds inboard of the containment isolation valves have been inspected in accordance with these requirements; no IGSCC indications have been observed. Also, to date,7 of the 20 (i.e., approximately 35 percent) BSEP, Unit 2 RWCU El-2

I system p' iping welds inboard of the containment isolation valves have been inspected in accordance with these requirements; no IGSCC indications have been observed.  ;

Criterion 3

Absence ofIGSCC Indications In RWCU Piping Welds Outboard of the Second

! Isolation Valve 1

l CP&L Basis:

Since replacement of the RWCU system piping, inspections performed in accordance with the ,

recommendations outlined in NRC Generic Letter 88-01 and NUREG-0313 have been i performed. To date,13 of the 82 (i.e., approximately 16 percent) susceptible BSEP, Unit 1, I RWCU system welds have been inspected in accordance with these requirements. Also, to date, 14 welds of the 83 (i.e., approximately 17 percent) susceptible BSEP, Unit 2, RWCU system piping welds have been inspected in accordance with the above requirements. No IGSCC indications have been detected in either RWCU system during these inspections.  :

Additional Criterion: Completion 0: 9RC Generic Letter 89-10," Safety-Related Motor- l l Operated Valve Testing And Surveillance"  !

CP&L Basis:

I While considering the PECO application, the NRC staff also reviewed PECO's actions and commitments regarding completion of all required actions for the RWCU system isolation valves i associated with NRC Generic Letter 89-10, " Safety-Related Motor-Operated Valve Testing And Surveillance." i For BSEP, the RWCU system containment isolation valves (i.e.,1-G31-F001,1-G31-F004, 2-G31-F001, and 2-G31-F004) are part of the NRC Generic Letter 89-10 MOV program. By letters dated June 21,1995, and April 12,1996, CP&L notified the NRC that implementation of the MOV program, in accordance with NRC Generic Letter 89-10, had been completed for BSEP, Units 1 and 2, respectively. However, during subsequent inspections, the NRC determined that implementation of Generic Letter 89-10 had not been satisfactorily completed for the RWCU system containment isolation valves. Specifically, the NRC identified concerns with valve factors used for double-disk gate valves; the RWCU system G31-F001 and F004 valves are double-disk gate valves. The results of these inspections for BSEP, Units 1 and 2, are i documented in Inspection Report Nos. 50-325,324/97-11 (Reference 2).

As result of these findings, CP&L subsequently upgraded valves 1-G31-F001 and 1-G31-F004 for uSEP, Unit I by installing larger capacity motors. The motor for valve 1-G31-F001 was L upgraded from 15 foot-pounds to 25 foot-pounds and the motor for valve 1-G31 F004 was upgraded from 10 foot-pounds to 25 foot-pounds. This motor upgrade provides an overall design margin for these valves of 12.7 percent and 13.6 percent, respectively. These design margins j include utilization of the Electric Power Research Institute (EPRI) Performance Prediction Program methodology for determining required thrust. The EPRI Performance Prediction Program methodology was accepted by the NRC (Reference 3), validated by EPRI, and l El-3 l

demonstrated t'o conservatively predict thrust requirements for motor-operated valves. The BSEP, Unit I upgrades were completed during Refueling Outage 11 (i.e., Spring 1998). To support NRC approval for elimination of the piping welds outboard of the second containment isolation valve in the RWCU systems from the inspection extent and frequency outlined in NRC Generic Letter 88-01, CP&L will complete similar upgrades of the 2-G31-F001 and 2-G31-F004 valves for BSEP, Unit 2. The upgrades will be completed prior to start-up from Refueling Outage 13 (i.e., B214RI), which is scheduled to begin on April 24,1999. These upgrades will complete implementation of Generic Letter 89-10 for these valves.

l Therefore, based on completion of upgrades to the valves 1-G31-F001 and 1-G31-F004 for i

BSEP, Unit 1, as well as the committed upgrades to valves 2-G31-F001 and 2-G31-F004 for l BSEP, Unit 2, CP&L will have completed implementation of the MOV program, in accordance with NRC Generic Letter 89-10, for these valves.

Additional Considerations:

An additional consideration is the significant accumulation of personnel radiation exposure

- associated with the augmented inspection of these welds. The personnel radiation exposure associated with these augmented inspections are dependent on the time needed to remove and l reinstall insulation, supports, and/or other interferences; prepare the weld for examination; and l perform the examinations. Based on the current augmented inspection schedule and the l remaining period of operation authorized by the BSEP operating licenses, approximately 65 person-rem of personnel radiation exposure savings could result from the approval of this l

request. ,

I CONCLUSION:

Based on the above, CP&L has committed to satisfy the NRC staff criteria previously used for i eliminating performance of augmented inspections on the subject welds and requests approval to

remove these welds from the inspection extent and frequency identified in NRC Generic l Letter 88-01 and NUREG-0313, Revision 2.

- The continued imposition of the augmented inspection recommendations specified in NRC Generic Letter 88-01 for this portion of the RWCU system constitutes a hardship to CP&L, particularly with regard to personnel radiation exposure, without a compensating increase in quality and safety. Approval of this request by February 1,1999,is necessary to support planning activities for BSEP, Unit 2, Refueling Outage 13 (i.e., B214RI). This refueling outage is scheduled to begin on April 17,1999.

REFERENCES:

} 1. Letter from Frank Rinaldi (NRC) to George A. Hunger (PECO Energy Company), "IGSCC Inspection Plan of RWCU System Piping Welds Outboard of the Primary Containment r

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l Isol'ation V'alves; Limerick Generating Station, Units 1 and 2 (TAC Nos. M92754 and M92755)," dated February 7,1996.

2. Letter from Milton B. Shymlock (NRC) to C. S. Ilinnant (CP&L), "'NRC Integrated

Inspection Report Nos. 50-325/97-1150-324/97-11 Notice of Violation," dated October 27, l

1997.

3. Letter from Ashok C. Thadani (NRC) to Thomas E. Tipton (NEI), " Electric Power Research Institute (EPRI) Topical Report TR-103237,'EPRI MOV Performance Prediction Program,'

Revision 1," dated March 15,1996.

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ENCLOSURE 2 BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS.1 AND 2 DOCKET NOS. 50-325 AND 50-324/ LICENSE NOS. DPR-71 AND DPR-62 INTERGRANULAR STRESS CORROSION CRACKING INSPECTION PLAN FOR REACTOR WATER CLEANUP SYSTEM PIPING WELDS OU fBOARD OF THE SECOND CONTAINMENT ISOLATION VALVE LIST OF REGULATORY COMMITMENTS The following table identifies those actions committed to by Carolina Power & Light (CP&L)

Company in this document. Any other actions discussed in the submittal represent intended or planned actions by CP&L. They are described for the NRC's information and are not regulatory commitments. Please notify the Manager - Regulatory Affairs at the Brunswick Steam Electric Plant of any questions regarding this document or any associated regulatory commitments.

Committed Commitment date or outage

1. Upgrade the motor-operators for valves 2-G31-F001 and Prior to 2-G31-F004 to address NRC Generic Letter 89-10 issues start-up from regarding double-disk gate valves. BSEP, Unit 2 Refueling Outage 13.

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