ML22240A098

Changes Related to AP1000 Gts Subsection 3.7.8, Main Steam Line Leakage

ML22240A098
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Issue date:	06/26/2015
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GTST AP1000- O48-3.7.8, Rev. 1

Advanced Passive 1000 (AP1000)

Generic Technical Specification Traveler (GTST)

Title:

Changes Related to LCO 3.7.8, Main Steam Line Leakage

I. Technical Specifications Task Force (TSTF) Travelers, Approved Since Revision 2 of STS NUREG-1431, and Used to Develop this GTST

TSTF Number and

Title:

None

STS NUREGs Affected:

Not Applicable

NRC Approval Date:

Not Applicable

TSTF Classification:

Not Applicable

Date report generated:

Friday, June 26, 2015 Page 1 GTST AP1000- O48-3.7.8, Rev. 1

II. Reference Combined License (RCOL) Standard Departures (Std. Dep.), RCOL COL Items, and RCOL Plant-Specific Technical Specifications (PTS) Changes Used to Develop this GTST

RCOL Std. Dep. Number and

Title:

There are no Vogtle departures applicable to Specification 3.7.8.

RCOL COL Item Number and

Title:

There are no Vogtle COL items applicable to Specification 3.7.8.

RCOL PTS Change Number and

Title:

VEGP LAR DOC A003: References to various Chapters and Sections of the Final Safety Analysis Report (FSAR) are revised to include FSAR.

VEGP LAR DOC A103: TS 3.7.8 editorial change

Date report generated:

Friday, June 26, 2015 Page 2 GTST AP1000- O48-3.7.8, Rev. 1

III. Comments on Relations Among TSTFs, RCOL Std. Dep., RCOL COL Items, and RCOL PTS Changes

This section discusses the considered changes that are: (1) applicable to operating reactor designs, but not to the AP1000 design; (2) already incorporated in the GTS; or (3) superseded by another change.

None

Date report generated:

Friday, June 26, 2015 Page 3 GTST AP1000- O48-3.7.8, Rev. 1

IV. Additional Changes Proposed as Part of this GTST (modifications proposed by NRC staff and/or clear editorial changes or deviations identified by preparer of GTST)

APOG Recommended Changes to Improve the Bases

Throughout the Bases, references to Sections and Chapters of the FSAR do not include the FSAR clarifier. Since these Section and Chapter references are to an external document, it is appropriate to include the FSAR modifier. (DOC A003)

Date report generated:

Friday, June 26, 2015 Page 4 GTST AP1000- O48-3.7.8, Rev. 1

V. Applicability

Affected Generic Technical Specifications and Bases:

Section 3.7.8, Main Steam Line Leakage

Changes to the Generic Technical Specifications and Bases:

The LCO Specification is revised by changing limited to to. This is consistent with TS Writer's Guide (Reference 4). (DOC A103)

GTS 3.7.8 Condition A is revised from exceeds operational limit to > 0.5 gpm. This is consistent with TS Writer's Guide (Reference 4) to state precise limit. (DOC A103)

The acronym FSAR is added to modify Section and Chapter in references to the FSAR throughout the Bases. (DOC A003) (APOG Comment)

Date report generated:

Friday, June 26, 2015 Page 5 GTST AP1000- O48-3.7.8, Rev. 1

VI. Traveler Information

Description of TSTF changes:

Not Applicable

Rationale for TSTF changes:

Not Applicable

Description of changes in RCOL Std. Dep., RCOL COL Item(s), and RCOL PTS Changes:

DOC A103 revises the GTS 3.7.8 LCO statement phrase limited to 0.5 gpm to 0.5 gpm.

The GTS 3.7.8 Condition A phrase exceeds operational limit is changed to > 0.5 gpm.

A more detailed description of each DOC can be found in Reference 2, VEGP TSU LAR, and the NRC staff safety evaluation can be found in Reference 3, VEGP LAR SER. The VEGP TSU LAR was modified in response to NRC staff RAIs in Reference 5 and the Southern Nuclear Operating Company RAI Response in Reference 6.

Rationale for changes in RCOL Std. Dep., RCOL COL Item(s), and RCOL PTS Changes:

DOC A103 is revised to use more precise language in accordance with the TS Writer's Guide (Reference 4).

Description of additional changes proposed by NRC staff/preparer of GTST:

The acronym FSAR is added to modify Section and Chapter in references to the FSAR throughout the Bases. (DOC A003) (APOG Comment)

Rationale for additional changes proposed by NRC staff/preparer of GTST :

Since Bases references to FSAR Sections and Chapters are to an external document, it is appropriate to include the FSAR modifier.

Date report generated:

Friday, June 26, 2015 Page 6 GTST AP1000- O48-3.7.8, Rev. 1

VII. GTST Safety Evaluation

Technical Analysis:

The changes are editorial, clarifying, grammatical, or otherwise considered administrative.

These changes do not affect the technical content, but improve the readability, implementation, and understanding of the requirements, and are therefore acceptable.

Having found that this GTSTs proposed changes to the GTS and Bases are acceptable, the NRC staff concludes that AP1000 STS Subsection 3.7.8 is an acceptable model Specification for the AP1000 standard reactor design.

References to Previous NRC Safety Evaluation Reports (SERs):

None

Date report generated:

Friday, June 26, 2015 Page 7 GTST AP1000- O48-3.7.8, Rev. 1

VIII. Review Information

Evaluator Comments:

None

Randy Belles Oak Ridge National Laboratory 865-574- 0388 bellesrj@ornl.gov

Review Information:

Availability for public review and comment on Revision 0 of this traveler approved by NRC staff on 5/19/2014.

APOG Comments (Ref. 7) and Resolutions:

1. (Internal # 3) Throughout the Bases, references to Sections and Chapters of the FSAR do not include the FSAR clarifier. Since these Section and Chapter references are to an external document, it is appropriate (DOC A003) to include the FSAR modifier. This is resolved by adding the FSAR modifier as appropriate.

2. (Internal # 7)Section VII, GTST Safety Evaluation, inconsistently completes the subsection References to Previous NRC Safety Evaluation Reports (SERs) by citing the associated SE for VEGP 3&4 COL Amendment 13. It is not clear whether there is a substantive intended difference when omitting the SE citation. This is resolved by removing the SE citation in Section VII of the GTST and ensuring that appropriate references to the consistent citation of this reference in Section X of the GTST are made.

NRC Final Approval Date: 6/26/2015

NRC

Contact:

T. R. Tjader United States Nuclear Regulatory Commission 301-415-1187 Theodore.Tjader@nrc.gov

Date report generated:

Friday, June 26, 2015 Page 8 GTST AP1000- O48-3.7.8, Rev. 1

IX. Evaluator Comments for Consideration in Finalizing Technical Specifications and Bases

None

Date report generated:

Friday, June 26, 2015 Page 9 GTST AP1000- O48-3.7.8, Rev. 1

X. References Used in GTST

1. AP1000 DCD, Revision 19, Section 16, Technical Specifications, June 2011 (ML11171A500).

2. Southern Nuclear Operating Company, Vogtle Electric Generating Plant, Units 3 and 4, Technical Specifications Upgrade License Amendment Request, February 24, 2011 (ML12065A057).

3. NRC Safety Evaluation (SE) for Amendment No. 13 to Combined License (COL) No. NPF-91 for Vogtle Electric Generating Plant (VEGP) Unit 3, and Amendment No. 13 to COL No.

NPF-92 for VEGP Unit 4, September 9, 2013, ADAMS Package Accession No.

ML13238A337, which contains:

ML13238A355 Cover Letter - Issuance of License Amendment No. 13 for Vogtle Units 3 and 4 (LAR 12- 002).

ML13238A359 Enclosure 1 - Amendment No. 13 to COL No. NPF-91 ML13239A256 Enclosure 2 - Amendment No. 13 to COL No. NPF-92 ML13239A284 Enclosure 3 - Revised plant-specific TS pages (Attachment to Amendment No. 13)

ML13239A287 Enclosure 4 - Safety Evaluation (SE), and Attachment 1 - Acronyms ML13239A288 SE Attachment 2 - Table A - Administrative Changes ML13239A319 SE Attachment 3 - Table M - More Restrictive Changes ML13239A333 SE Attachment 4 - Table R - Relocated Specifications ML13239A331 SE Attachment 5 - Table D - Detail Removed Changes ML13239A316 SE Attachment 6 - Table L - Less Restrictive Changes

The following documents were subsequently issued to correct an administrative error in Enclosure 3:

ML13277A616 Letter - Correction To The Attachment (Replacement Pages) - Vogtle Electric Generating Plant Units 3 and 4-Issuance of Amendment Re:

Technical Specifications Upgrade (LAR 12- 002) (TAC No. RP9402)

ML13277A637 Enclosure 3 - Revised plant-specific TS pages (Attachment to Amendment No. 13) (corrected)

4. TSTF-GG-05-01, Writer's Guide for Plant-Specific Improved Technical Specifications, June 2005.

5. RAI Letter No. 01 Related to License Amendment Request (LAR) 12- 002 for the Vogtle Electric Generating Plant Units 3 and 4 Combined Licenses, September 7, 2012 (ML12251A355).

6. Southern Nuclear Operating Company, Vogtle Electric Generating Plant, Units 3 and 4, Response to Request for Additional Information Letter No. 01 Related to License Amendment Request LAR 002, ND 2015, October 04, 2012 (ML12286A363 and ML12286A360)

Date report generated:

Friday, June 26, 2015 Page 10 GTST AP1000- O48-3.7.8, Rev. 1

7. APOG-2014- 008, APOG (AP1000 Utilities) Comments on AP1000 Standardized Technical Specifications (STS) Generic Technical Specification Travelers (GTSTs), Docket ID NRC-2014- 0147, September 22, 2014 (ML14265A493).

Date report generated:

Friday, June 26, 2015 Page 11 GTST AP1000- O48-3.7.8, Rev. 1

XI. MARKUP of the Applicable GTS Subsection for Preparation of the STS NUREG

The entire section of the Specifications and the Bases associated with this GTST is presented next.

Changes to the Specifications and Bases are denoted as follows: Deleted portions are marked in strikethrough red font, and inserted portions in bold blue font.

Date report generated:

Friday, June 26, 2015 Page 12 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage 3.7.8

3.7 PLANT SYSTEMS

3.7.8 Main Steam Line Leakage

LCO 3.7.8 Main Steam Line leakage through the pipe walls inside containment shall be limedo 5 gpm.

ICABILIT MODES,, 3,.

AIO

NDITION QD AION COMPLETNE

MStm Li A.1 Be in MODE 3. 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> leak > 0.5 gpm exceeds operational AND limit.

A.2 Be in MODE 5. 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />

SURVEILLANCE REQUIREMENTS

SURVEILLANCE FREQUENCY

SR 3.7.8.1 Verify main steam line leakage into the containment merR sump 0.5 gpm.

AP1000 STS 3.7.8-1 Amendment 0Rev. 0 Revision 19 Date report generated:

Friday, June 26, 2015 Page 13 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage B 3.7.8

B 3.7 PLANT SYSTEMS

B 3.7.8 Main Steam Line Leakage

BASES

BACKGROUND A limit on leakage from the main steam line inside containment is required to limit system operation in the presence of excessive leakage.

Leakage is limited to an amount which would not compromise safety consistent with the Leak-Before-Break (LBB) analysis discussed in FSAR Chapter 3 (Ref. 1). This leakage limit ensures appropriate action can be taken before the integrity of the lines is impaired.

LBB is an argument which allows elimination of design for dynamic load effects of postulated pipe breaks. The fundamental premise of LBB is that the materials used in nuclear plant piping are strong enough that even a large through wall crack leaking well in excess of rates detectable by present leak detection systems would remain stable, and would not result in a double-ended guillotine break under maximum loading conditions. The benefit of LBB is the elimination of pipe whip restraints, jet impingement effects, subcompartment pressurization, and internal system blowdown loads.

As described in FSAR Section 3.6 (Ref. 1), LBB has been applied to the main steam line pipe runs inside containment. Hence, the potential safety significance of secondary side leaks inside containment requires detection and monitoring of leakage inside containment. This LCO protects the main steam lines inside containment against degradation, and helps assure that serious leaks will not develop. The consequences of violating this LCO include the possibility of further degradation of the main steam lines, which may lead to pipe break.

APPLICABLE The safety significance of plant leakage inside containment varies SAFETY depending on its source, rate, and duration. Therefore, detection and ANALYSES monitoring of plant leakage inside containment are necessary. This is accomplished via the instrumentation required by LCO 3.4.9, RCS Leakage Detection Instrumentation, and the Reactor Coolant System (RCS) water inventory balance (SR 3.4.7.1). Subtracting RCS leakage as well as any other identified non-RCS leakage into the containment area from the total plant leakage inside containment provides qualitative information to the operators regarding possible main steam line leakage.

This allows the operators to take corrective action should leakage occur which is detrimental to the safety of the facility and/or the public.

AP1000 STS B 3.7.8-1 Amendment 0Rev. 0 Revision 19 Date report generated:

Friday, June 26, 2015 Page 14 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage B 3.7.8

BASES

APPLICABLE SAFETY ANALYSES (continued)

Although the main steam line leakage limit is not required by the 10 CFR 50.36(c)(2)(ii) criteria, this specification has been included in Technical Specifications in accordance with NRC direction (Ref. 2).

LCO Main steam line leakage is defined as leakage inside containment in any portion of the two (2) main steam line pipe walls. Up to 0.5 gpm of leakage is allowable because it is below the leak rate for LBB analyzed cases of a main steam line crack twice as long as a crack leaking at ten (10) times the detectable leak rate under normal operating load conditions. Violation of this LCO could result in continued degradation of the main steam line.

APPLICABILITY Because of elevated main steam system temperatures and pressures, the potential for main steam line leakage is greatest in MODES 1, 2, 3, and 4.

In MODES 5 and 6, a main steam line leakage limit is not provided because the main steam system pressure is far lower, resulting in lower stresses and a reduced potential for leakage. In addition, the steam generators are not the primary method of RCS heat removal in MODES 5 and 6.

ACTIONS A.1 and A.2

With main steam line leakage in excess of the LCO limit, the unit must be brought to lower pressure conditions to reduce the severity of the leakage and its potential consequences. The reactor must be placed in MODE 3 with 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. This action reduces the main steam line pressure and leakage, and also reduces the factors which tend to degrade the main steam lines. The Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to reach MODE 3 from full power without challenging plant systems is reasonable based on operating experience. Similarly, the Completion Time of 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> to reach MODE 5 without challenging plant systems is also reasonable based on operating experience. In MODE 5, the pressure stresses acting on the main steam line are much lower, and further deterioration of the main steam line is less likely.

AP1000 STS B 3.7.8-2 Amendment 0Rev. 0 Revision 19 Date report generated:

Friday, June 26, 2015 Page 15 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage B 3.7.8

BASES

SURVEILLANCE SR 3.7.8.1 REQUIREMENTS Verifying that main steam line leakage is within the LCO limit assures the integrity of those lines inside containment is maintained. An early warning of main steam line leakage is provided by the automatic system which monitors the containment sump level. Main steam line leakage would appear as unidentified leakage inside containment via this system, and can only be positively identified by inspection. However, by performance of an RCS water inventory balance (SR 3.4.7.1) and evaluation of the cooling and chilled water systems inside containment, determination of whether the main steam line is a potential source of unidentified leakage inside containment is possible.

REFERENCES 1. FSAR Section 3.6, Protection Against the Dynamic Effects Associated with the Postulated Rupture of Piping.

2. NRC letter, Diane T. Jackson to Westinghouse (Nicholas J.

Liparulo), dated September 5, 1996, Staff Update to Draft Safety Evaluation Report (DSER) Open Items (OIs) Regarding the Westinghouse AP600 Advanced Reactor Design, Open Item #365.

AP1000 STS B 3.7.8-3 Amendment 0Rev. 0 Revision 19 Date report generated:

Friday, June 26, 2015 Page 16 GTST AP1000- O48-3.7.8, Rev. 1

XII. Applicable STS Subsection After Incorporation of this GTSTs Modifications

The entire subsection of the Specifications and the Bases associated with this GTST, following incorporation of the modifications, is presented next.

Date report generated:

Friday, June 26, 2015 Page 17 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage 3.7.8

3.7 PLANT SYSTEMS

3.7.8 Main Steam Line Leakage

LCO 3.7.8 Main Steam Line leakage through the pipe walls inside containment shall be 0.5 g.

ICABILIT MODEp,, 3,.

AIO

NDITION QD AION COMmLETNE

Mptm Li 1 Be inO. s leak > 0.5 gpm.

A

2 Be inO. 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />

pURsEILLANCE REQMEp

pURsEILLANCE FQNCY

pR 3 sify mn steamieakage itontnment merR sump 0.5 gpm.

AP1000 STS 3.7.8-1 Rev. 0

Date report generated:

Friday, June 26, 2015 Page 18 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage B 3.7.8

B 3.7 PLANT SYSTEMS

B 3.7.8 Main Steam Line Leakage

BASES

BACKGROUND A limit on leakage from the main steam line inside containment is required to limit system operation in the presence of excessive leakage.

Leakage is limited to an amount which would not compromise safety consistent with the Leak-Before-Break (LBB) analysis discussed in FSAR Chapter 3 (Ref. 1). This leakage limit ensures appropriate action can be taken before the integrity of the lines is impaired.

LBB is an argument which allows elimination of design for dynamic load effects of postulated pipe breaks. The fundamental premise of LBB is that the materials used in nuclear plant piping are strong enough that even a large through wall crack leaking well in excess of rates detectable by present leak detection systems would remain stable, and would not result in a double-ended guillotine break under maximum loading conditions. The benefit of LBB is the elimination of pipe whip restraints, jet impingement effects, subcompartment pressurization, and internal system blowdown loads.

As described in FSAR Section 3.6 (Ref. 1), LBB has been applied to the main steam line pipe runs inside containment. Hence, the potential safety significance of secondary side leaks inside containment requires detection and monitoring of leakage inside containment. This LCO protects the main steam lines inside containment against degradation, and helps assure that serious leaks will not develop. The consequences of violating this LCO include the possibility of further degradation of the main steam lines, which may lead to pipe break.

APPLICABLE The safety significance of plant leakage inside containment varies SAFETY depending on its source, rate, and duration. Therefore, detection and ANALYSES monitoring of plant leakage inside containment are necessary. This is accomplished via the instrumentation required by LCO 3.4.9, RCS Leakage Detection Instrumentation, and the Reactor Coolant System (RCS) water inventory balance (SR 3.4.7.1). Subtracting RCS leakage as well as any other identified non-RCS leakage into the containment area from the total plant leakage inside containment provides qualitative information to the operators regarding possible main steam line leakage.

This allows the operators to take corrective action should leakage occur which is detrimental to the safety of the facility and/or the public.

AP1000 STS B 3.7.8-1 Rev. 0

Date report generated:

Friday, June 26, 2015 Page 19 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage B 3.7.8

BASES

APPLICABLE SAFETY ANALYSES (continued)

Although the main steam line leakage limit is not required by the 10 CFR 50.36(c)(2)(ii) criteria, this specification has been included in Technical Specifications in accordance with NRC direction (Ref. 2).

LCO Main steam line leakage is defined as leakage inside containment in any portion of the two (2) main steam line pipe walls. Up to 0.5 gpm of leakage is allowable because it is below the leak rate for LBB analyzed cases of a main steam line crack twice as long as a crack leaking at ten (10) times the detectable leak rate under normal operating load conditions. Violation of this LCO could result in continued degradation of the main steam line.

APPLICABILITY Because of elevated main steam system temperatures and pressures, the potential for main steam line leakage is greatest in MODES 1, 2, 3, and 4.

In MODES 5 and 6, a main steam line leakage limit is not provided because the main steam system pressure is far lower, resulting in lower stresses and a reduced potential for leakage. In addition, the steam generators are not the primary method of RCS heat removal in MODES 5 and 6.

ACTIONS A.1 and A.2

With main steam line leakage in excess of the LCO limit, the unit must be brought to lower pressure conditions to reduce the severity of the leakage and its potential consequences. The reactor must be placed in MODE 3 with 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. This action reduces the main steam line pressure and leakage, and also reduces the factors which tend to degrade the main steam lines. The Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> to reach MODE 3 from full power without challenging plant systems is reasonable based on operating experience. Similarly, the Completion Time of 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> to reach MODE 5 without challenging plant systems is also reasonable based on operating experience. In MODE 5, the pressure stresses acting on the main steam line are much lower, and further deterioration of the main steam line is less likely.

AP1000 STS B 3.7.8-2 Rev. 0

Date report generated:

Friday, June 26, 2015 Page 20 GTST AP1000- O48-3.7.8, Rev. 1

Main Steam Line Leakage B 3.7.8

BASES

SURVEILLANCE SR 3.7.8.1 REQUIREMENTS Verifying that main steam line leakage is within the LCO limit assures the integrity of those lines inside containment is maintained. An early warning of main steam line leakage is provided by the automatic system which monitors the containment sump level. Main steam line leakage would appear as unidentified leakage inside containment via this system, and can only be positively identified by inspection. However, by performance of an RCS water inventory balance (SR 3.4.7.1) and evaluation of the cooling and chilled water systems inside containment, determination of whether the main steam line is a potential source of unidentified leakage inside containment is possible.

REFERENCES 1. FSAR Section 3.6, Protection Against the Dynamic Effects Associated with the Postulated Rupture of Piping.

2. NRC letter, Diane T. Jackson to Westinghouse (Nicholas J.

Liparulo), dated September 5, 1996, Staff Update to Draft Safety Evaluation Report (DSER) Open Items (OIs) Regarding the Westinghouse AP600 Advanced Reactor Design, Open Item #365.

AP1000 STS B 3.7.8-3 Rev. 0

Date report generated:

Friday, June 26, 2015 Page 21