ML22240A077

Changes Related to AP1000 Gts Subsection 3.5.5, PRHR HX Shutdown, RCS Intact

ML22240A077
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Issue date:	04/20/2015
From:	NRC/NRR/DSS/STSB
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Craig Harbuck NRR/DSS 301-415-3140
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GTST AP1000-P05-3.5.5, Rev. 1 Advanced Passive 1000 (AP1000)

Generic Technical Specification Traveler (GTST)

Title:

Changes Related to LCO 3.5.5, Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Shutdown, Reactor Coolant System (RCS) Intact 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:

TSTF-425, Rev. 3, Relocate Surveillance Frequencies to Licensee Control - RITSTF Initiative 5b TSTF-523, Rev. 2, Generic Letter 2008-01, Managing Gas Accumulation STS NUREGs Affected:

TSTF-425, Rev. 3: NUREG-1430, 1431, 1432, 1433, 1434 TSTF-523, Rev. 2: NUREG-1430, 1431, 1432, 1433, 1434 NRC Approval Date:

TSTF-425, Rev. 3: 06-Jul-09 TSTF-523, Rev. 2: 23-Dec-13 TSTF Classification:

TSTF-425, Rev. 3: Technical Change TSTF-523, Rev. 2: Technical Change Date report generated:

Monday, April 20, 2015 Page 1

GTST AP1000-P05-3.5.5, 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:

None RCOL COL Item Number and

Title:

None RCOL PTS Change Number and

Title:

VEGP LAR DOC A073: Editorial revision to add system name PRHR HX to valve description VEGP LAR DOC A075: TS 3.5.5 Condition E deletion of second entry condition VEGP LAR DOC A076: TS 3.5.5 Required Action E.1 revision VEGP LAR DOC M10: PRHR HX LCO Note replaced with SR VEGP LAR DOC L17: Revisions to Actions and SRs associated with noncondensible gases Date report generated:

Monday, April 20, 2015 Page 2

GTST AP1000-P05-3.5.5, 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(1) applicable to operating reactor designs, but not to the AP1000 design; (2) already incorporated in the GTS; or (3) superseded by another change.

TSTF-425 is deferred for future consideration.

TSTF-523, Rev. 1 is not applicable to the GTS. The issues of gas accumulation have been addressed by GTS Rev.19.

Date report generated:

Monday, April 20, 2015 Page 3

GTST AP1000-P05-3.5.5, 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)

Applicability statement is revised to correct the punctuation after ...Removal System (RNS).

from a period to a comma.

APOG Recommended Changes to Improve the Bases An editorial change is made to the Actions section of the Bases under the heading C.1 by changing the word revise to remove.

Date report generated:

Monday, April 20, 2015 Page 4

GTST AP1000-P05-3.5.5, Rev. 1 V. Applicability Affected Generic Technical Specifications and Bases:

Subsection 3.5.5, Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Shutdown, Reactor Coolant System (RCS) Intact Changes to the Generic Technical Specifications and Bases:

LCO 3.5.5 Note is replaced with a SR (SR 3.5.4.4 referred to by SR 3.5.5.1) to verify PRHR HX OPERABILITY when one or more RCPs are in operation and the associated LCO section of the Bases is revised to reflect deletion of the Note. The associated SR section of the Bases is revised to reflect addition of the new SR. (DOC M10)

Applicability statement is revised to correct punctuation.

Condition A entry statement and Required Action A.1 of TS 3.5.5, the system name PRHR HX is added to identify the valves. (DOC A073)

Condition C entry statement of TS 3.5.5 is changed from Presence of non-condensible gases in the high point vent. to PRHR HX inlet line noncondensible gas volume not within limit.

Required Action C.1 of TS 3.5.5 is changed from Vent noncondensible gases. to Restore PRHR HX inlet line noncondensible gas volume to within limit. The associated LCO section of the Bases is also revised. (DOC L17)

Condition E second entry statement of TS 3.5.5 is deleted. The associated Actions section of the Bases is also revised. (DOC A075)

Required Action E.1 of TS 3.5.5 is revised by deleting the statement and > 20% pressurizer level. The associated Actions section of the Bases is also revised. (A076)

In the Actions section of the Bases under the heading C.1 an editorial correction is made by changing the word revise to remove. (APOG Comment)

Date report generated:

Monday, April 20, 2015 Page 5

GTST AP1000-P05-3.5.5, Rev. 1 VI. Traveler Information Description of TSTF changes:

None Rationale for TSTF changes:

None Description of changes in RCOL Std. Dep., RCOL COL Item(s), and RCOL PTS Changes:

VEGP LAR DOC A073 adds the system name PRHR HX to the valve description for TS 3.5.5 Condition A entry statement and Required Action A.1.

VEGP LAR DOC A075 deletes the second entry statement of Condition E.

VEGP LAR DOC A076 deletes the requirement of a > 20% pressurizer level. Required Action E.1 is revised to Initiate action to be in MODE 5 with RCS pressure boundary open.

VEGP LAR DOC M10 replaces LCO 3.5.5 Note, which states When any reactor coolant pumps (RCPs) are operating, at least one RCP must be operating in the loop with the PRHR HX, Loop 1, with a SR to verify PRHR HX OPERABILITY when one or more RCPs are in operation.

VEGP LAR DOC L17 revises the TS 3.5.5 Condition C entry statement to change Presence of non-condensible gases in the high point vent. to PRHR HX inlet line noncondensible gas volume not within limit. Required Action C.1 is revised to reflect the change to the revised Condition C statement.

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

VEGP LAR DOC A073 changes to TS 3.5.5 Condition A entry statement and Required Action A.1 provide clarity in citing the full name of the valve, PRHR HX.

VEGP LAR DOC A075 removes the second entry condition of Condition E, which states LCO not met for reasons other than A, B, C, or D. Condition D is required to be entered if there are PRHR HX inoperabilities other than those described by Condition A, B, or C. If the PRHR HX is not restored to Operable status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of entering Condition D, Condition E is required to be entered.

VEGP LAR DOC A076 Change to Required Action E.1 and associated Bases does not change the intent of the Required Action. Once MODE 5 is entered with the RCS pressure boundary open the requirement for > 20% pressurizer level is no longer applicable.

VEGP LAR DOC M10 replacement of LCO 3.5.5 Note with a SR to verify PRHR HX OPERABILITY when one or more RCPs are in operation.

Date report generated:

Monday, April 20, 2015 Page 6

GTST AP1000-P05-3.5.5, Rev. 1 VEGP LAR DOC L17 changes TS 3.5.5 Condition C entry statement and LCO section of the Bases for consistency with LCO section of the Bases of TS 3.5.4. The changes to TS 3.5.5 Required Action C.1 are for consistency with changes made to Condition C entry statement.

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

The Applicability statement is revised by changing the period after ...Removal System (RNS).

to a comma.

In the Actions section of the Bases under the heading C.1 the last sentence is corrected from

...available to revise heat... to available to remove heat.... (APOG Comment)

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

The change to the Applicability statement is a correction to the punctuation.

changing the word revise to remove is an editorial correction.

Date report generated:

Monday, April 20, 2015 Page 7

GTST AP1000-P05-3.5.5, Rev. 1 VII. GTST Safety Evaluation Technical Analysis:

VEGP LAR DOC M10:

GTS 3.5.4, Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Operating, and GTS 3.5.5, Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Shutdown, Reactor Coolant System (RCS) Intact, are revised to delete the LCO Note.

GTS LCO 3.5.5 requires that the PRHR HX shall be Operable. The LCO has a Note which states, When any reactor coolant pumps (RCPs) are operating, at least one RCP must be operating in the loop with the PRHR HX, Loop 1. The Bases for LCO 3.5.5 state that the Note requires a reactor coolant pump (RCP) to be operating in the loop with the PRHR HX, Loop 1, if any RCPs are operating. If RCPs are only operating in Loop 2 and no RCPs are operating in Loop 1, there is a possibility there may be reverse flow in the PRHR HX. An operational condition such as this should be surveillance tested to ensure that it is met. Accordingly, the Note requirements are replaced by a new SR 3.5.4.4 to periodically verify one Loop 1 RCP is in operation, but which is only required to be met when one or more RCPs are in operation.

A corresponding SR is not explicitly stated in Specification 3.5.5 because SR 3.5.5.1 states that the SRs of Specification 3.5.4 are applicable. Thus, the new SR added to Specification 3.5.4 will also be applicable to Specification 3.5.5.

VEGP LAR DOC L17: As stated in the associated Bases for the GTS 3.5.5 Actions, the presence of some noncondensible gases does not mean that the CMT is immediately inoperable, but that gases are collecting and should be vented. TS 3.5.5, Condition C is revised for consistency.

GTS 3.5.5, Required Action C.1 is revised to replace a specific method of restoration with a more general action to restore the parameter, in this case noncondensible gas volume, to within its limit. This change is made for consistency with the revised entry conditions associated with the Required Action. Only the specific method is deleted from the action. The associated Bases, both GTS and revised, describe an appropriate method for restoration. The revised Action continue to provide assurance that operation with a noncondensible gas volume that can affect the associated flow path is allowed for only a limited period of time. These changes are designated as less restrictive because the specific method of restoration is deleted and replaced with a more general requirement to restore within the limit.

Other Changes: The remaining 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 3.5.5 is an acceptable model Specification for the AP1000 standard reactor design.

Date report generated:

Monday, April 20, 2015 Page 8

GTST AP1000-P05-3.5.5, Rev. 1 References to Previous NRC Safety Evaluation Reports (SERs):

None Date report generated:

Monday, April 20, 2015 Page 9

GTST AP1000-P05-3.5.5, Rev. 1 VIII. Review Information Evaluator Comments:

None Steve Short Pacific Northwest National Laboratory 509-375-2868 steve.short@pnnl.gov Review Information:

Availability for public review and comment on Revision 0 of this traveler approved by NRC staff on 5/23/2014.

APOG Comments (Ref. 7) and Resolutions:

1. (Internal #2) Approved TSTF-523 is not dispositioned in the material provided to support the GTSTs. Include TSTF-523 in the reference disposition tables, as TSTF deferred for future consideration. This is resolved by dispositioningTSTF-523, Rev. 1 as not applicable to the GTS and stating that the concerns of the TSTF have been addressed by GTS Rev.19.

2. (Internal #6) The GTST sections often repeat VEGP LAR DOCs, which reference existing and current requirements. The inclusion in the GTST of references to existing and current, are not always valid in the context of the GTS. Each occurrence of existing and current should be revised to be clear and specific to GTS, MTS, or VEGP COL TS (or other), as appropriate. This is resolved by making the APOG recommended changes to the GTST.

3. (Internal #13) The NRC approval of TSTF-425, and model safety evaluation provided in the CLIIP for TSTF-425, are generically applicable to any designs Technical Specifications. As such, the replacement of certain Frequencies with a Surveillance Frequency Control Program should be included in the GTST for AP1000 STS NUREG.

However, implementation in the AP1000 STS should not reflect optional (i.e., bracketed) material showing retention of fixed Surveillance Frequencies where relocation to a Surveillance Frequency Control Program is acceptable. Since each represented AP1000 Utility is committed to maintaining standardization, there is no rationale for an AP1000 STS that includes bracketed options.

Consistent with TSTF-425 criteria, replace applicable Surveillance Frequencies with In accordance with the Surveillance Frequency control Program and add that Program as new AP1000 STS Specification 5.5.15. NRC Staff disagrees with implementing TSTF-425. The TSTF is deferred for future consideration.

4. (Internal #306) Fifth item under Changes to the Generic Technical Specifications and Bases describing changes to Condition E second entry statement as attributed to DOC A076. However, this change is actually discussed in DOC A075. Replace the reference to Date report generated:

Monday, April 20, 2015 Page 10

GTST AP1000-P05-3.5.5, Rev. 1 DOC A076 with DOC A075. This is resolved by making the recommended correction to the GTST.

5. (Internal #307) Sixth item under Changes to the Generic Technical Specifications and Bases describing changes to Required Action E.1 as attributed to DOC A075. However, this change is actually discussed in DOC A076. Replace the reference to DOC A075 with DOC A076. This is resolved by making the recommended correction to the GTST.

6. (Internal #308) Editorial change for clarity - These changes are made for consistency with the TS requirement(s) being discussed in the TS Bases. Make the following changes to LCO Bases:

A reactor coolant pump (RCP) is required to be operating in the loop with the PRHR HX, Loop...

The markup error is corrected by removing the strikethrough from the added A.

7. Editorial change is recommended. These non-technical changes provide improved clarity, consistency, and operator usability. Make the following changes in the C.1 Actions Bases discussion:

A Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is acceptable, considering that passive feed and bleed cooling is available to reviseremove heat from the RCS.

This is resolved by making the recommended correction.

NRC Final Approval Date: 4/20/2015 NRC

Contact:

Derek Scully United States Nuclear Regulatory Commission 301-415-6972 Derek.Scully@nrc.gov Date report generated:

Monday, April 20, 2015 Page 11

GTST AP1000-P05-3.5.5, Rev. 1 IX. Evaluator Comments for Consideration in Finalizing Technical Specifications and Bases None Date report generated:

Monday, April 20, 2015 Page 12

GTST AP1000-P05-3.5.5, 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. 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-12-002, ND-12-2015, October 04, 2012 (ML12286A363 and ML12286A360).

4. TSTF-GG-05-01, Writer's Guide for Plant-Specific Improved Technical Specifications, June 2005 (ML070660229).

5. 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)

6. 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).

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:

Monday, April 20, 2015 Page 13

GTST AP1000-P05-3.5.5, Rev. 1 Date report generated:

Monday, April 20, 2015 Page 14

GTST AP1000-P05-3.5.5, 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:

Monday, April 20, 2015 Page 15

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact 3.5.5 3.5 PASSIVE CORE COOLING SYSTEM (PXS) 3.5.5 Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Shutdown, Reactor Coolant System (RCS) Intact LCO 3.5.5 The PRHR HX shall be OPERABLE.

---

NOTE---------------------------------------------

When any reactor coolant pumps (RCPs) are operating, at least one RCP must be operating in the loop with the PRHR HX, Loop 1.

APPLICABILITY: MODE 4 with the RCS cooling provided by the Normal Residual Heat Removal System (RNS).,

MODE 5 with the RCS pressure boundary intact and pressurizer level 20%.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One air operated PRHR A.1 Restore air operated PRHR 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> HX outlet isolation valve HX outlet valve to inoperable. OPERABLE status.

B. One air operated In- B.1 Restore air operated 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Containment Refueling IRWST gutter isolation Water Storage Tank valve to OPERABLE status.

(IRWST) gutter isolation valve inoperable.

C. Presence of non- C.1 Vent noncondensible 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> condensible gases in the gasesRestore PRHR HX high point ventPRHR HX inlet line noncondensible inlet line gas volume to within noncondensible gas limit.

volume not within limit.

AP1000 STS 3.5.5-1 Amendment 0Rev. 0 Revision 19 Date report generated:

Monday, April 20, 2015 Page 16

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact 3.5.5 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME D. PRHR HX inoperable for D.1 Restore PRHR HX to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> reasons other than OPERABLE status.

Condition A, B, or C.

E. Required Action and E.1 Initiate action to be in Immediately associated Completion MODE 5 with the RCS Time not met. pressure boundary open and > 20% pressurizer OR level.

LCO not met for reasons other than A, B, C, or D.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.5.1 The SRs of Specification 3.5.4, Passive Residual In accordance Heat Removal Heat Exchanger (PRHR HX) - with applicable Operating - are applicable. SRs AP1000 STS 3.5.5-2 Amendment 0Rev. 0 Revision 19 Date report generated:

Monday, April 20, 2015 Page 17

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact B 3.5.5 B 3.5 PASSIVE CORE COOLING SYSTEM (PXS)

B 3.5.5 Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Shutdown, Reactor Coolant System (RCS) Intact BASES BACKGROUND A description of the PRHR HX is provided in the Bases for LCO 3.5.4, Passive Residual Heat Removal Heat Exchanger (PRHR HX) -

Operating.

APPLICABLE In the event of a loss of normal decay heat removal capability during SAFETY shutdown with the Reactor Coolant System (RCS) pressure boundary ANALYSES intact, the PRHR HX provides the preferred safety related heat removal path. When required, the PRHR HX is manually actuated and can maintain the RCS < 420°F. Alternatively, the heat removal function can be provided by depressurizing the RCS with the Automatic Depressurization System (ADS) and injection of the In-containment Refueling Water Storage Tank (IRWST) with containment closure capability provided. The PRHR HX is preferred because the RCS pressure boundary remains intact, thus preserving a barrier to fission product release.

The PRHR HX satisfies Criterion 3 of 10 CFR 50.36(c)(2)(ii).

LCO This LCO requires the PRHR HX to be OPERABLE so that it can be placed in service in the event normal decay heat removal capability is lost. Since this a passive component, it does not require the actuation of active components such as pumps for its OPERABILITY and will be OPERABLE if the inlet valves are in their normally open position, and the normally closed, fail open outlet valves open on receipt of an actuation signal.

In addition to the appropriate valve configuration, OPERABILITY may be impaired by flow blockage caused by noncondensible gases collecting in the system. Thus the absence of non-condensible gases in the high point is necessary for system OPERABILITY.OPERABILITY is not expected to be challenged due to small gas accumulations in the high point, and rapid gas accumulations are not expected during plant operation. However, a relatively small gas volume was incorporated into the design for alerting operators to provide sufficient time to initiate venting operations before the gas volume would be expected to increase to a sufficient volume that might AP1000 STS B 3.5.5-1 Amendment 0Rev. 0 Revision 19 Date report generated:

Monday, April 20, 2015 Page 18

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact B 3.5.5 BASES LCO (continued) potentially challenge the OPERABILITY of passive safety injection flow. Therefore, noncondensible gas accumulation in the injection line high point that causes the water level to drop below the sensor will require operator action to investigate the cause of the gas accumulation and to vent the associated high point(s).

The note requires aA reactor coolant pump (RCP) is required to be operating in the loop with the PRHR HX, Loop 1, if any RCPs are operating. If RCPs are only operating in loop 2 and no RCPs are operating in loop 1, there is a possibility there may be reverse flow in the PRHR HX.

APPLICABILITY The PRHR HX must be OPERABLE in MODE 4 with RCS cooling provided by the Normal Residual Heat Removal System (RNS) and in MODE 5 with the RCS pressure boundary intact and pressurizer level 20% to provide decay heat removal in the event the normal residual heat removal system is not available.

The PRHR HX requirements in MODES 1, 2, 3, and 4 with RCS cooling not provided by the RNS are specified in LCO 3.5.4, Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Operating.

The PRHR HX is not capable of natural circulation cooling of the RCS in MODE 5 with either the RCS pressure boundary open or with the RCS intact when pressurizer level 20%, or in MODE 6.

ACTIONS A.1 The outlet line from the PRHR HX is isolated by a pair of normally closed, fail open, air operated valves, arranged in parallel. They are redundant, and if either valve is OPERABLE the system can function at 100%

capacity, assuming other OPERABILITY conditions are met.

Since these valves are redundant, if one valve is inoperable, a Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> has been allowed to restore the inoperable valve to OPERABLE status. This Completion Time is consistent with the Completion Times specified for other parallel redundant safety related systems.

AP1000 STS B 3.5.5-2 Amendment 0Rev. 0 Revision 19 Date report generated:

Monday, April 20, 2015 Page 19

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact B 3.5.5 BASES ACTIONS (continued)

B.1 With one air operated IRWST gutter isolation valve inoperable, the remaining isolation valve can function to drain the gutter to the IRWST.

Action must be taken to restore the inoperable gutter isolation valve to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time is acceptable based on the capability of the remaining valve to perform 100% of the required safety function assumed in the safety analyses.

C.1 At the inlet piping high point there is a vertical chamber which serves as a collection point for noncondensible gases. This collection point is provided with detectors which alarm to indicate when gases have collected in this area. The presence of an alarm does not mean that PRHR HX is immediately inoperable, but that gases are collecting and should be vented. A Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is acceptable, considering that passive feed and bleed cooling is available to reviseremove heat from the RCS.

D.1 With the LCO not met for reasons other than Condition A, B, or C, the PRHR HX must be restored within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time is acceptable based on the availability of passive feed and bleed cooling to provide RCS heat removal. The effectiveness of feed and bleed cooling is discussed in the bases for LCO 3.5.4, Action E.1.

E.1 If any of the above Required Actions have not been accomplished in the required Completion Time, or the LCO is not met for reasons other than Conditions A, B, C, or D, action must be initiated, immediately, to be in MODE 5 with the RCS pressure boundary open and pressurizer level 20%. The time to RCS boiling is maximized in the event of loss of normal decay heat removal capability, by maintaining a visible level in the pressurizer. Additionally, inIn this MODE with the RCS must be opened, such that safety related decay heat removal can be immediately initiated by actuation of the IRWST injection valve(s).

AP1000 STS B 3.5.5-3 Amendment 0Rev. 0 Revision 19 Date report generated:

Monday, April 20, 2015 Page 20

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact B 3.5.5 BASES SURVEILLANCE SR 3.5.5.1 REQUIREMENTS The LCO 3.5.4 Surveillance Requirements are applicable to the PRHR HX required to be OPERABLE. The Frequencies associated with each specified SR are applicable. Refer to the corresponding Bases for LCO 3.5.4 for a discussion of each SR.

REFERENCES None.

AP1000 STS B 3.5.5-4 Amendment 0Rev. 0 Revision 19 Date report generated:

Monday, April 20, 2015 Page 21

GTST AP1000-P05-3.5.5, 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:

Monday, April 20, 2015 Page 22

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact 3.5.5 3.5 PASSIVE CORE COOLING SYSTEM (PXS) 3.5.5 Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Shutdown, Reactor Coolant System (RCS) Intact LCO 3.5.5 The PRHR HX shall be OPERABLE.

APPLICABILITY: MODE 4 with the RCS cooling provided by the Normal Residual Heat Removal System (RNS),

MODE 5 with the RCS pressure boundary intact and pressurizer level 20%.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. One air operated PRHR A.1 Restore air operated PRHR 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> HX outlet isolation valve HX outlet valve to inoperable. OPERABLE status.

B. One air operated In- B.1 Restore air operated 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Containment Refueling IRWST gutter isolation Water Storage Tank valve to OPERABLE status.

(IRWST) gutter isolation valve inoperable.

C. PRHR HX inlet line C.1 Restore PRHR HX inlet line 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> noncondensible gas noncondensible gas volume volume not within limit. to within limit.

D. PRHR HX inoperable for D.1 Restore PRHR HX to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> reasons other than OPERABLE status.

Condition A, B, or C.

AP1000 STS 3.5.5-1 Rev. 0 Date report generated:

Monday, April 20, 2015 Page 23

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact 3.5.5 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME E. Required Action and E.1 Initiate action to be in Immediately associated Completion MODE 5 with the RCS Time not met. pressure boundary open.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.5.1 The SRs of Specification 3.5.4, Passive Residual In accordance Heat Removal Heat Exchanger (PRHR HX) - with applicable Operating - are applicable. SRs AP1000 STS 3.5.5-2 Rev. 0 Date report generated:

Monday, April 20, 2015 Page 24

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact B 3.5.5 B 3.5 PASSIVE CORE COOLING SYSTEM (PXS)

B 3.5.5 Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Shutdown, Reactor Coolant System (RCS) Intact BASES BACKGROUND A description of the PRHR HX is provided in the Bases for LCO 3.5.4, Passive Residual Heat Removal Heat Exchanger (PRHR HX) -

Operating.

APPLICABLE In the event of a loss of normal decay heat removal capability during SAFETY shutdown with the Reactor Coolant System (RCS) pressure boundary ANALYSES intact, the PRHR HX provides the preferred safety related heat removal path. When required, the PRHR HX is manually actuated and can maintain the RCS < 420°F. Alternatively, the heat removal function can be provided by depressurizing the RCS with the Automatic Depressurization System (ADS) and injection of the In-containment Refueling Water Storage Tank (IRWST) with containment closure capability provided. The PRHR HX is preferred because the RCS pressure boundary remains intact, thus preserving a barrier to fission product release.

The PRHR HX satisfies Criterion 3 of 10 CFR 50.36(c)(2)(ii).

LCO This LCO requires the PRHR HX to be OPERABLE so that it can be placed in service in the event normal decay heat removal capability is lost. Since this a passive component, it does not require the actuation of active components such as pumps for its OPERABILITY and will be OPERABLE if the inlet valves are in their normally open position, and the normally closed, fail open outlet valves open on receipt of an actuation signal.

OPERABILITY is not expected to be challenged due to small gas accumulations in the high point, and rapid gas accumulations are not expected during plant operation. However, a relatively small gas volume was incorporated into the design for alerting operators to provide sufficient time to initiate venting operations before the gas volume would be expected to increase to a sufficient volume that might potentially challenge the OPERABILITY of passive safety injection flow. Therefore, noncondensible gas accumulation in the injection line high point that causes the water level to drop below the sensor will require operator action to investigate the cause of the gas accumulation and to vent the associated high point(s).

AP1000 STS B 3.5.5-1 Rev. 0 Date report generated:

Monday, April 20, 2015 Page 25

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact B 3.5.5 BASES LCO (continued)

A reactor coolant pump (RCP) is required to be operating in the loop with the PRHR HX, Loop 1, if any RCPs are operating. If RCPs are only operating in loop 2 and no RCPs are operating in loop 1, there is a possibility there may be reverse flow in the PRHR HX.

APPLICABILITY The PRHR HX must be OPERABLE in MODE 4 with RCS cooling provided by the Normal Residual Heat Removal System (RNS) and in MODE 5 with the RCS pressure boundary intact and pressurizer level 20% to provide decay heat removal in the event the normal residual heat removal system is not available.

The PRHR HX requirements in MODES 1, 2, 3, and 4 with RCS cooling not provided by the RNS are specified in LCO 3.5.4, Passive Residual Heat Removal Heat Exchanger (PRHR HX) - Operating.

The PRHR HX is not capable of natural circulation cooling of the RCS in MODE 5 with either the RCS pressure boundary open or with the RCS intact when pressurizer level 20%, or in MODE 6.

ACTIONS A.1 The outlet line from the PRHR HX is isolated by a pair of normally closed, fail open, air operated valves, arranged in parallel. They are redundant, and if either valve is OPERABLE the system can function at 100%

capacity, assuming other OPERABILITY conditions are met.

Since these valves are redundant, if one valve is inoperable, a Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> has been allowed to restore the inoperable valve to OPERABLE status. This Completion Time is consistent with the Completion Times specified for other parallel redundant safety related systems.

B.1 With one air operated IRWST gutter isolation valve inoperable, the remaining isolation valve can function to drain the gutter to the IRWST.

Action must be taken to restore the inoperable gutter isolation valve to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Completion Time is acceptable based on the capability of the remaining valve to perform 100% of the required safety function assumed in the safety analyses.

AP1000 STS B 3.5.5-2 Rev. 0 Date report generated:

Monday, April 20, 2015 Page 26

GTST AP1000-P05-3.5.5, Rev. 1 PRHR HX - Shutdown, RCS Intact B 3.5.5 BASES ACTIONS (continued)

C.1 At the inlet piping high point there is a vertical chamber which serves as a collection point for noncondensible gases. This collection point is provided with detectors which alarm to indicate when gases have collected in this area. The presence of an alarm does not mean that PRHR HX is immediately inoperable, but that gases are collecting and should be vented. A Completion Time of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is acceptable, considering that passive feed and bleed cooling is available to remove heat from the RCS.

D.1 With the LCO not met for reasons other than Condition A, B, or C, the PRHR HX must be restored within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time is acceptable based on the availability of passive feed and bleed cooling to provide RCS heat removal. The effectiveness of feed and bleed cooling is discussed in the bases for LCO 3.5.4, Action E.1.

E.1 If any of the above Required Actions have not been accomplished in the required Completion Time, action must be initiated, immediately, to be in MODE 5 with the RCS pressure boundary open. In this MODE with the RCS opened, safety related decay heat removal can be immediately initiated by actuation of the IRWST injection valve(s).

SURVEILLANCE SR 3.5.5.1 REQUIREMENTS The LCO 3.5.4 Surveillance Requirements are applicable to the PRHR HX required to be OPERABLE. The Frequencies associated with each specified SR are applicable. Refer to the corresponding Bases for LCO 3.5.4 for a discussion of each SR.

REFERENCES None.

AP1000 STS B 3.5.5-3 Rev. 0 Date report generated:

Monday, April 20, 2015 Page 27