RA-16-0001, Response to Request for Additional Information Regarding Application to Revise Technical Specifications to Adopt TSTF-523, Revision 2, Generic Letter 2008-01, Managing Gas Accumulation.

Response to Request for Additional Information Regarding Application to Revise Technical Specifications to Adopt TSTF-523, Revision 2, Generic Letter 2008-01, Managing Gas Accumulation.

ML16018A001
Person / Time
Site:	Harris, Brunswick
Issue date:	01/18/2016
From:	Repko R Duke Energy Progress
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
GL-08-001, RA-16-0001, TAC MF6413, TAC MF6414, TAC MF6415, TAC MF6416, TAC MF6417, TAC MF6418, TAC MF6419, TAC MF6420, TAC MF6421, TAC MF6422
Download: ML16018A001 (7)

Text

Regis T. Repko 526 South Church Street Charlotte, NC 28202 Mailing Address:

Mail Code EC07H / P.O. Box 1006 Charlotte, NC 28201-1006 704-382-4126 704-382-6056 fax Serial: RA-16-0001 10 CFR 50.90 January 18, 2016 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS. 1 AND 2 DOCKET NOS. 50-325 AND 50-324 / RENEWED LICENSE NOS. DPR-71 AND DPR-62 SHEARON HARRIS NUCLEAR POWER PLANT, UNIT 1 DOCKET NO. 50-400 / RENEWED LICENSE NO. NPF-63

SUBJECT:

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING APPLICATION TO REVISE TECHNICAL SPECIFICATIONS TO ADOPT TSTF-523, REVISION 2, GENERIC LETTER 2008-01, MANAGING GAS ACCUMULATION

REFERENCES:

1. Duke Energy letter RA-15-0006, Brunswick Steam Electric Plant, Unit Nos. 1 and 2, Shearon Harris Nuclear Power Plant, Unit 1, Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3, Application to Revise Technical Specifications to Adopt TSTF-523, Revision 2, Generic Letter 2008-01, Managing Gas Accumulation, Using the Consolidated Line Item Improvement Process, dated June 24, 2015 (ADAMS Accession No. ML15175A438)

2. NRC letter, Brunswick Steam Electric Plant, Units 1 and 2; Shearon Harris Nuclear Power Plant, Unit 1; Catawba Nuclear Station, Units 1 and 2; McGuire Nuclear Station, Units 1 and 2; and Oconee Nuclear Station, Units 1, 2, and 3: Request for Additional Information Regarding Change to Quality Assurance Topical Report [sic](TAC Nos.

MF6413 through MF 6422), dated November 19, 2015 (ADAMS Accession No. ML15320A386)

By letter dated June 24, 2015 (Reference 1), Duke Energy Progress, Inc., and Duke Energy Carolinas, LLC, collectively referred to henceforth as Duke Energy, submitted a request for amendments to the Technical Specifications (TSs) for Brunswick Steam Electric Plant, Unit Nos. 1 and 2 (BSEP); Shearon Harris Nuclear Power Plant, Unit 1 (HNP); Catawba Nuclear Station, Units 1 and 2 (CNS); McGuire Nuclear Station, Units 1 and 2 (MNS); and Oconee Nuclear Station, Units 1, 2, and 3 (ONS). By letter dated November 19, 2015 (Reference 2), the NRC staff provided a Request for Additional Information (RAI) regarding the June 24, 2015, license amendment application, applicable to BSEP and HNP. The Attachment provides Duke Energys response to the November 19, 2015, RAI.

U.S. Nuclear Regulatory Commission RA-16-0001 Page2 The information provided in this letter does not affect the conclusions of the significant hazards consideration determination or the environmental evaluation included in the June 24, 2015, license amendment application.

This submittal contains no new regulatory commitments. In accordance with 10 CFR 50.91, Duke Energy is transmitting a copy of this letter and attachment to the designated State Officials. Should you have any questions concerning this letter, or require additional information, please contact Art Zaremba, Manager - Nuclear Fleet Licensing, at 980-373-2062.

I declare under penalty of perjury that the foregoing is true and correct. Executed on January 18, 2016.

Sincerely,

~*

Regis T. Repko Sr. Vice President - Governance, Projects, and Engineering MKL

Attachment:

Response to NRC Request for Additional Information cc: (all with Attachment)

L. D. Wert, USNRC Region II - Regional Administrator (acting)

M. P. Catts, USNRC Resident Inspector - BSEP J. D. Austin, USNRC Resident Inspector - HNP A. Hon, NRR Project Manager - BSEP M. C. Barillas, NRR Project Manager - HNP J. A. Whited, NRR Project Manager W. L. Cox, Ill, Chief, Division of Health Service Regulation, RP Section (NC)

Chair - North Carolina Utilities Commission

Attachment RA-16-0001 Page 1 of 5 RESPONSE TO NRC REQUEST FOR ADDITIONAL INFORMATION NRC Comment: By letter dated June 24, 2015,1 Duke Energy Progress, Inc., and Duke Energy Carolinas, LLC (Duke Energy) submitted a license amendment request (LAR) for U.S. Nuclear Regulatory Commission (NRC) approval for several of its reactor sites. The proposed change would revise or add Technical Specification (TS) Surveillance Requirements (SRs) to verify that the system locations susceptible to gas accumulation are sufficiently filled with water and to provide allowances which permit performance of the verification. These changes are requested to address concerns discussed in NRC Generic Letter 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems.2 Duke Energy stated in its LAR that the proposal was consistent with Technical Specifications Task Force (TSTF) Traveler - 523, Revision 2, Generic Letter 2008-01, Managing Gas Accumulation.3 Contrary to the above statement, in its LAR, Duke Energy proposed a 92-day surveillance frequency for Brunswick SRs 3.5.1.1, 3.5.3.1, and 3.6.2.3.3 and Shearon Harris SR 4.6.2.1.e.

This differs from the 31-day surveillance frequency for the SRs requested for the other referenced sites. The NRC Model Safety Evaluation,4 specifies a 31-day surveillance frequency for the SRs. The NRC staff has reviewed the licensees submittal and determined that responses to the following Request for Additional Information (RAI) questions are needed to clarify the proposed 92-day frequency, and to complete its review.

1. Please provide the Brunswick surveillance history regarding gas accumulation, starting in 2008, that includes the surveillance date; the location; the measured, allowable, and as-left void volumes; the number of days since the last surveillance; the TS surveillance frequency; and clarification comments. Please do not include surveillance detail that determined existence of a water-solid condition. Please include the total number of Brunswick surveillances.

Duke Energy Response:

Table 1 provides the requested surveillance history data for the time period from October 2008 (site submittal of the nine-month response to NRC GL 2008-01) through November 2015 for the BSEP Emergency Core Cooling System Surveillance Requirement (SR) 3.5.1.1, Reactor Core Isolation Cooling (RCIC) System (proposed new SR 3.5.3.1),

and Residual Heat Removal (RHR) Suppression Pool Cooling System (proposed new SR 3.6.2.3.3). The total number of surveillances performed in this time period is provided in Table 2.

2. The proposed Technical Specification Bases for Brunswick SR 3.4.7.2, as submitted with the LAR, state, in part, that:

Gas accumulation in the RHR shutdown cooling (SDC) suction flow path is satisfactorily addressed by procedures which fill the system prior to placing SDC in service.

1 Agencywide Documents Access and Management System (ADAMS) Accession No. ML15175A438.

2 ADAMS Accession No. ML072910759.

3 ADAMS Accession No. ML13053A075.

4 ADAMS Accession No. ML13255A169.

Attachment RA-16-0001 Page 2 of 5 Is a follow-up measurement of high point voids conducted to assess the acceptability of the filling process?

Duke Energy Response:

The proposed Technical Specification Bases is consistent with the BSEP response to NRC Generic Letter 2008-01, submitted to the NRC by letter dated October 10, 2008 (ADAMS Accession No. ML082950466). Page 4 of the Enclosure to this letter included the following:

Gas accumulation in the RHR shutdown cooling (SDC) suction flow path is satisfactorily addressed by procedures which fill the system prior to placing SDC in service. Since the non-safety shutdown cooling mode of RHR is manually initiated at a low reactor pressure, sufficient time is available to ensure fill and warm-up of the flow path have been performed prior to RHR pump start to avoid any unacceptable pressure transients on the system.

By NRC letter dated June 24, 2011 (ADAMS Accession No. ML100890025), the NRC closed out their review of the BSEP response to NRC GL 2008-01.

Confirmatory ultrasonic testing (UT) inspections of the SDC suction flow path are performed after the SDC system is initially filled and vented following a drain down of the system in support of maintenance.

Plant operating procedures do not require that UT inspections be performed following fill and vent evolutions for initial system startup in the SDC mode of RHR. Since the SDC mode of RHR is manually initiated, there is sufficient time to ensure fill and warmup of the flow path prior to RHR pump start, thereby avoiding any unacceptable pressure transients on the system.

3. Please provide justification for selection of a 92-day frequency in Shearon Harris SR 4.6.2.1.e. Please include the RAI 1 and 2 information categories in the response when applicable.

Duke Energy Response:

Table 3 provides the requested surveillance history data for the time period from October 2008 (site submittal of the nine-month response to NRC GL 2008-01) through November 2015 for the HNP Containment Spray System (proposed new SR 4.6.2.1.e). The total number of surveillances performed in this time period was 90.

As described in the June 24, 2015 Duke Energy license amendment application, there is a small permanent void near valve 1CT-12 that was first identified in February 2008. The volume of the void was originally estimated as 257 in3 (0.15 ft3), but was subsequently reduced to approximately 10 in3 (0.005 ft3) with the installation of a local vent valve in 2010.

A void of approximately this size still exists. This permanent void is not reflected in Table 3.

The allowable void size at this location is 0.34 ft3.

RAI 2 is not applicable to HNP in that the proposed Technical Specification Bases for HNP does not include a statement similar to that quoted for BSEP.

Attachment RA-16-0001 Page 3 of 5 Table 1 Brunswick Surveillance History Measured Allowable As-Left Number of Surv. Void Void Void Days Surv. Freq.

Location Comments Date Volume Volume Volume Since Last (days)

(ft3) (ft3) (ft3) Surv.

9/24/10 Core Spray unknown 3 0 28 31 Entrained air was indicated when the vent Loop 1B at valve was opened. An assessment judged Vent Valve that the volume of entrained air was small 1-E21-V5005 (i.e., less than the Allowable Void Volume) and did not challenge system operability.

The Allowable Void Volume is the acceptance criteria at the time the void was discovered.

Attachment RA-16-0001 Page 4 of 5 Table 2 Brunswick Surveillance Count Total Surveillances System Unit/Loop Performed*

Residual Heat Removal 1A 87 Residual Heat Removal 1B 89 Residual Heat Removal 2A 89 Residual Heat Removal 2B 90 Core Spray 1A 90 Core Spray 1B 90 Core Spray 2A 90 Core Spray 2B 88 High Pressure Coolant Injection Unit 1 86 High Pressure Coolant Injection Unit 2 87 Reactor Core Isolation Cooling Unit 1 88 Reactor Core Isolation Cooling Unit 2 87

• October 2008 through November 2015

Attachment RA-16-0001 Page 5 of 5 Table 3 Shearon Harris Surveillance History Measured Allowable As-Left Number of Surv. Void Void Void Days Surv. Freq.

Location Comments Date Volume Volume Volume Since Last (days)

(ft3) (ft3) (ft3) Surv.

8/26/13 Just 0.05 See See 76 91 There was no numerical criterion for upstream of comments comments allowable void volume at this location at Containment the time of discovery. The as-found void Isolation was evaluated as acceptable using the site Valve operability determination process. The void 1CT-50 on A was subsequently vented, resulting in a Containment small residual void which dissipated over Spray Pump time. No void was found on the subsequent Discharge quarterly check.

Text

Regis T. Repko 526 South Church Street Charlotte, NC 28202 Mailing Address:

Mail Code EC07H / P.O. Box 1006 Charlotte, NC 28201-1006 704-382-4126 704-382-6056 fax Serial: RA-16-0001 10 CFR 50.90 January 18, 2016 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS. 1 AND 2 DOCKET NOS. 50-325 AND 50-324 / RENEWED LICENSE NOS. DPR-71 AND DPR-62 SHEARON HARRIS NUCLEAR POWER PLANT, UNIT 1 DOCKET NO. 50-400 / RENEWED LICENSE NO. NPF-63

SUBJECT:

RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION REGARDING APPLICATION TO REVISE TECHNICAL SPECIFICATIONS TO ADOPT TSTF-523, REVISION 2, GENERIC LETTER 2008-01, MANAGING GAS ACCUMULATION

REFERENCES:

1. Duke Energy letter RA-15-0006, Brunswick Steam Electric Plant, Unit Nos. 1 and 2, Shearon Harris Nuclear Power Plant, Unit 1, Catawba Nuclear Station, Units 1 and 2, McGuire Nuclear Station, Units 1 and 2, and Oconee Nuclear Station, Units 1, 2, and 3, Application to Revise Technical Specifications to Adopt TSTF-523, Revision 2, Generic Letter 2008-01, Managing Gas Accumulation, Using the Consolidated Line Item Improvement Process, dated June 24, 2015 (ADAMS Accession No. ML15175A438)

2. NRC letter, Brunswick Steam Electric Plant, Units 1 and 2; Shearon Harris Nuclear Power Plant, Unit 1; Catawba Nuclear Station, Units 1 and 2; McGuire Nuclear Station, Units 1 and 2; and Oconee Nuclear Station, Units 1, 2, and 3: Request for Additional Information Regarding Change to Quality Assurance Topical Report [sic](TAC Nos.

MF6413 through MF 6422), dated November 19, 2015 (ADAMS Accession No. ML15320A386)

By letter dated June 24, 2015 (Reference 1), Duke Energy Progress, Inc., and Duke Energy Carolinas, LLC, collectively referred to henceforth as Duke Energy, submitted a request for amendments to the Technical Specifications (TSs) for Brunswick Steam Electric Plant, Unit Nos. 1 and 2 (BSEP); Shearon Harris Nuclear Power Plant, Unit 1 (HNP); Catawba Nuclear Station, Units 1 and 2 (CNS); McGuire Nuclear Station, Units 1 and 2 (MNS); and Oconee Nuclear Station, Units 1, 2, and 3 (ONS). By letter dated November 19, 2015 (Reference 2), the NRC staff provided a Request for Additional Information (RAI) regarding the June 24, 2015, license amendment application, applicable to BSEP and HNP. The Attachment provides Duke Energys response to the November 19, 2015, RAI.

U.S. Nuclear Regulatory Commission RA-16-0001 Page2 The information provided in this letter does not affect the conclusions of the significant hazards consideration determination or the environmental evaluation included in the June 24, 2015, license amendment application.

This submittal contains no new regulatory commitments. In accordance with 10 CFR 50.91, Duke Energy is transmitting a copy of this letter and attachment to the designated State Officials. Should you have any questions concerning this letter, or require additional information, please contact Art Zaremba, Manager - Nuclear Fleet Licensing, at 980-373-2062.

I declare under penalty of perjury that the foregoing is true and correct. Executed on January 18, 2016.

Sincerely,

~*

Regis T. Repko Sr. Vice President - Governance, Projects, and Engineering MKL

Attachment:

Response to NRC Request for Additional Information cc: (all with Attachment)

L. D. Wert, USNRC Region II - Regional Administrator (acting)

M. P. Catts, USNRC Resident Inspector - BSEP J. D. Austin, USNRC Resident Inspector - HNP A. Hon, NRR Project Manager - BSEP M. C. Barillas, NRR Project Manager - HNP J. A. Whited, NRR Project Manager W. L. Cox, Ill, Chief, Division of Health Service Regulation, RP Section (NC)

Chair - North Carolina Utilities Commission

Attachment RA-16-0001 Page 1 of 5 RESPONSE TO NRC REQUEST FOR ADDITIONAL INFORMATION NRC Comment: By letter dated June 24, 2015,1 Duke Energy Progress, Inc., and Duke Energy Carolinas, LLC (Duke Energy) submitted a license amendment request (LAR) for U.S. Nuclear Regulatory Commission (NRC) approval for several of its reactor sites. The proposed change would revise or add Technical Specification (TS) Surveillance Requirements (SRs) to verify that the system locations susceptible to gas accumulation are sufficiently filled with water and to provide allowances which permit performance of the verification. These changes are requested to address concerns discussed in NRC Generic Letter 2008-01, Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems.2 Duke Energy stated in its LAR that the proposal was consistent with Technical Specifications Task Force (TSTF) Traveler - 523, Revision 2, Generic Letter 2008-01, Managing Gas Accumulation.3 Contrary to the above statement, in its LAR, Duke Energy proposed a 92-day surveillance frequency for Brunswick SRs 3.5.1.1, 3.5.3.1, and 3.6.2.3.3 and Shearon Harris SR 4.6.2.1.e.

This differs from the 31-day surveillance frequency for the SRs requested for the other referenced sites. The NRC Model Safety Evaluation,4 specifies a 31-day surveillance frequency for the SRs. The NRC staff has reviewed the licensees submittal and determined that responses to the following Request for Additional Information (RAI) questions are needed to clarify the proposed 92-day frequency, and to complete its review.

1. Please provide the Brunswick surveillance history regarding gas accumulation, starting in 2008, that includes the surveillance date; the location; the measured, allowable, and as-left void volumes; the number of days since the last surveillance; the TS surveillance frequency; and clarification comments. Please do not include surveillance detail that determined existence of a water-solid condition. Please include the total number of Brunswick surveillances.

Duke Energy Response:

Table 1 provides the requested surveillance history data for the time period from October 2008 (site submittal of the nine-month response to NRC GL 2008-01) through November 2015 for the BSEP Emergency Core Cooling System Surveillance Requirement (SR) 3.5.1.1, Reactor Core Isolation Cooling (RCIC) System (proposed new SR 3.5.3.1),

and Residual Heat Removal (RHR) Suppression Pool Cooling System (proposed new SR 3.6.2.3.3). The total number of surveillances performed in this time period is provided in Table 2.

2. The proposed Technical Specification Bases for Brunswick SR 3.4.7.2, as submitted with the LAR, state, in part, that:

Gas accumulation in the RHR shutdown cooling (SDC) suction flow path is satisfactorily addressed by procedures which fill the system prior to placing SDC in service.

1 Agencywide Documents Access and Management System (ADAMS) Accession No. ML15175A438.

2 ADAMS Accession No. ML072910759.

3 ADAMS Accession No. ML13053A075.

4 ADAMS Accession No. ML13255A169.

Attachment RA-16-0001 Page 2 of 5 Is a follow-up measurement of high point voids conducted to assess the acceptability of the filling process?

Duke Energy Response:

The proposed Technical Specification Bases is consistent with the BSEP response to NRC Generic Letter 2008-01, submitted to the NRC by letter dated October 10, 2008 (ADAMS Accession No. ML082950466). Page 4 of the Enclosure to this letter included the following:

Gas accumulation in the RHR shutdown cooling (SDC) suction flow path is satisfactorily addressed by procedures which fill the system prior to placing SDC in service. Since the non-safety shutdown cooling mode of RHR is manually initiated at a low reactor pressure, sufficient time is available to ensure fill and warm-up of the flow path have been performed prior to RHR pump start to avoid any unacceptable pressure transients on the system.

By NRC letter dated June 24, 2011 (ADAMS Accession No. ML100890025), the NRC closed out their review of the BSEP response to NRC GL 2008-01.

Confirmatory ultrasonic testing (UT) inspections of the SDC suction flow path are performed after the SDC system is initially filled and vented following a drain down of the system in support of maintenance.

Plant operating procedures do not require that UT inspections be performed following fill and vent evolutions for initial system startup in the SDC mode of RHR. Since the SDC mode of RHR is manually initiated, there is sufficient time to ensure fill and warmup of the flow path prior to RHR pump start, thereby avoiding any unacceptable pressure transients on the system.

3. Please provide justification for selection of a 92-day frequency in Shearon Harris SR 4.6.2.1.e. Please include the RAI 1 and 2 information categories in the response when applicable.

Duke Energy Response:

Table 3 provides the requested surveillance history data for the time period from October 2008 (site submittal of the nine-month response to NRC GL 2008-01) through November 2015 for the HNP Containment Spray System (proposed new SR 4.6.2.1.e). The total number of surveillances performed in this time period was 90.

As described in the June 24, 2015 Duke Energy license amendment application, there is a small permanent void near valve 1CT-12 that was first identified in February 2008. The volume of the void was originally estimated as 257 in3 (0.15 ft3), but was subsequently reduced to approximately 10 in3 (0.005 ft3) with the installation of a local vent valve in 2010.

A void of approximately this size still exists. This permanent void is not reflected in Table 3.

The allowable void size at this location is 0.34 ft3.

RAI 2 is not applicable to HNP in that the proposed Technical Specification Bases for HNP does not include a statement similar to that quoted for BSEP.

Attachment RA-16-0001 Page 3 of 5 Table 1 Brunswick Surveillance History Measured Allowable As-Left Number of Surv. Void Void Void Days Surv. Freq.

Location Comments Date Volume Volume Volume Since Last (days)

(ft3) (ft3) (ft3) Surv.

9/24/10 Core Spray unknown 3 0 28 31 Entrained air was indicated when the vent Loop 1B at valve was opened. An assessment judged Vent Valve that the volume of entrained air was small 1-E21-V5005 (i.e., less than the Allowable Void Volume) and did not challenge system operability.

The Allowable Void Volume is the acceptance criteria at the time the void was discovered.

Attachment RA-16-0001 Page 4 of 5 Table 2 Brunswick Surveillance Count Total Surveillances System Unit/Loop Performed*

Residual Heat Removal 1A 87 Residual Heat Removal 1B 89 Residual Heat Removal 2A 89 Residual Heat Removal 2B 90 Core Spray 1A 90 Core Spray 1B 90 Core Spray 2A 90 Core Spray 2B 88 High Pressure Coolant Injection Unit 1 86 High Pressure Coolant Injection Unit 2 87 Reactor Core Isolation Cooling Unit 1 88 Reactor Core Isolation Cooling Unit 2 87

• October 2008 through November 2015

Attachment RA-16-0001 Page 5 of 5 Table 3 Shearon Harris Surveillance History Measured Allowable As-Left Number of Surv. Void Void Void Days Surv. Freq.

Location Comments Date Volume Volume Volume Since Last (days)

(ft3) (ft3) (ft3) Surv.

8/26/13 Just 0.05 See See 76 91 There was no numerical criterion for upstream of comments comments allowable void volume at this location at Containment the time of discovery. The as-found void Isolation was evaluated as acceptable using the site Valve operability determination process. The void 1CT-50 on A was subsequently vented, resulting in a Containment small residual void which dissipated over Spray Pump time. No void was found on the subsequent Discharge quarterly check.