ML22240A075
| ML22240A075 | |
| Person / Time | |
|---|---|
| Issue date: | 04/20/2015 |
| From: | NRC/NRR/DSS/STSB |
| To: | |
| Craig Harbuck NRR/DSS 301-415-3140 | |
| Shared Package | |
| ML22240A001 | List:
|
| References | |
| Download: ML22240A075 (24) | |
Text
GTST AP1000-P03-3.5.3, Rev. 1 Advanced Passive 1000 (AP1000)
Generic Technical Specification Traveler (GTST)
Title:
Changes Related to LCO 3.5.3, Core Makeup Tanks (CMTs) - 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-359-A, Rev. 9, Increase Flexibility in MODE Restraints 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-359-A, Rev. 9: NUREG-1430, 1431, 1432, 1433, 1434 TSTF-425, Rev. 3: NUREG-1430, 1431, 1432, 1433, 1434 TSTF-523, Rev. 2: NUREG-1430, 1431, 1432, 1433, 1434 NRC Approval Date:
TSTF-359-A, Rev. 9: 12-May-03 TSTF-425, Rev. 3: 06-Jul-09 TSTF-523, Rev. 2: 23-Dec-13 TSTF Classification:
TSTF-359-A, Rev. 9: Technical Change TSTF-425, Rev. 3: Technical Change TSTF-523, Rev. 2: Technical Change Date report generated:
Monday, April 20, 2015 Page 1
GTST AP1000-P03-3.5.3, 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 A069: TS 3.5.3 Condition C revision VEGP LAR DOC A070: TS 3.5.3 Required Action D.1 revision VEGP LAR DOC A071: TS 3.5.3 revision to Condition associated with water temperature and boron concentration VEGP LAR DOC A072: TS 3.5.3 Condition D entry statement revision VEGP LAR DOC L01: Added SR for valve actuation Date report generated:
Monday, April 20, 2015 Page 2
GTST AP1000-P03-3.5.3, 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(1) applicable to operating reactor designs, but not to the AP1000 design; (2) already incorporated in the GTS; or (3) superseded by another change.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-359-A is deferred for future consideration.
TSTF-425 is deferred for future consideration.
TSTF-523, Rev. 2 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-P03-3.5.3, 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 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)
An editorial change is made to the Actions section of the Bases, under heading A.1. The change clarifies and corrects the first use of the acronym ECCS by using the full phrase emergency core cooling system and deleting system after ECCS.
Date report generated:
Monday, April 20, 2015 Page 4
GTST AP1000-P03-3.5.3, Rev. 1 V. Applicability Affected Generic Technical Specifications and Bases:
Section 3.5.3, Core Makeup Tanks (CMTs) - Shutdown, Reactor Coolant System (RCS) Intact Changes to the Generic Technical Specifications and Bases:
Applicability statement is revised to correct punctuation.
Condition B of TS 3.5.3 is revised from Required CMT inoperable due to one or more parameters (water temperature, boron concentration) not within limits. to Required CMT inoperable due to water temperature or boron concentration not within limits. (DOC A071)
Required Action B.1 of TS 3.5.3 is revised from Restore water temperature or boron concentration to within limits. to Restore water temperature and boron concentration to within limits. (DOC A071)
Condition C of TS 3.5.3 is revised by adding the word Condition before ...A or B. (DOC A069)
Condition D and associated Bases of TS 3.5.3 is revised by deleting the second entry statement LCO not met for reasons other than A, B, or C. (DOC A072)
Required Action D.1 and associated Bases of TS 3.5.3 is revised from Initiate action to be in MODE 5 with RCS pressure boundary open and 20% pressurizer level. to Initiate action to be in MODE 5 with RCS pressure boundary open. (DOC A070)
In the Actions section of the Bases, under heading A.1 the last sentence is revised by changing ECCS system to emergency core cooling system (ECCS). (APOG Comment)
The Bases for SR 3.5.3.1 is revised by updating the reference SR 3.5.2.7 to SR 3.5.2.8.
(DOC L01)
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:
Monday, April 20, 2015 Page 5
GTST AP1000-P03-3.5.3, 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 A069 corrects Condition C of TS 3.5.3 by adding the word Condition before
...A or B.
VEGP LAR DOC A070 revises Required Action D.1 and associated Bases of TS 3.5.3 from Initiate action to be in MODE 5 with RCS pressure boundary open and 20% pressurizer level. to Initiate action to be in MODE 5 with RCS pressure boundary open.
VEGP LAR DOC A071 revises Condition B entry statement by specifying the parameters not within limits as water temperature or boron concentration. Required Action B.1 is revised to state that both water temperature and boron concentration need to be restored to within limits.
VEGP LAR DOC A072 revises Condition D and associated Bases by deleting the second entry statement.
VEGP LAR DOC L01 revises Bases for SR 3.5.3.1 by updating the referenced SR from SR 3.5.2.7 to SR 3.5.2.8.
Rationale for changes in RCOL Std. Dep., RCOL COL Item(s), and RCOL PTS Changes:
The VEGP LAR DOC A069 change to Condition C entry statement provides consistency with the writer's guide, TSTF-GG-05-01.
The VEGP LAR DOC A070 change to Required Action D.1 and associated Bases does not change the intent of the Required Action. Once the RCS pressure Boundary is open in MODE 5 the 20% pressurizer level is no longer applicable.
The VEGP LAR DOC A071 change to Condition B entry statement to specify the parameters of water temperature and boron concentration provides clarification. The change to Required Action B.1 to specify both water temperature and boron concentration need to be restored within limits also provides clarification.
VEGP LAR DOC A072 removes the second entry condition of Condition D since it is a duplicate entry condition to Condition C.
The VEGP LAR DOC L01 change to the referenced SRs in the Bases for SR 3.5.3.1 is an editorial change due to the addition of new SR 3.5.2.7 in STS 3.5.2.
Date report generated:
Monday, April 20, 2015 Page 6
GTST AP1000-P03-3.5.3, Rev. 1 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.
The phrase ECCS system is clarified and corrected to emergency core cooling system (ECCS) in the Actions section of the Bases, under heading A.1. (APOG Comment)
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:
The change to the Applicability statement is a correction to the punctuation.
The change from ECCS system to emergency core cooling system (ECCS) is an editorial clarification and the correction is in conformance with TSTF-GG-05-01, section 3.2.2.a. These non-technical changes provide improved clarity, consistency, and operator usability.
Since Bases references to FSAR Sections and Chapters are to an external document, it is appropriate to include the FSAR modifier.
Date report generated:
Monday, April 20, 2015 Page 7
GTST AP1000-P03-3.5.3, Rev. 1 VII. GTST Safety Evaluation Technical Analysis:
The changes to TS 3.5.3 and associated Bases 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 3.5.3 is an acceptable model Specification for the AP1000 standard reactor design.
References to Previous NRC Safety Evaluation Reports (SERs):
None Date report generated:
Monday, April 20, 2015 Page 8
GTST AP1000-P03-3.5.3, 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. 5) 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 #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.
- 3. (Internal #11) Remove TSTF-359-A from the GTST. Include TSTF-359-A in the reference disposition tables, as TSTF deferred for future consideration. The justification for TSTF-359 was based on vendor-specific evaluations. For Westinghouse plants, that evaluation was in MUHP-3015, Qualitative Risk Assessment Supporting Increased Flexibility in Mode Restraints, January 2002. This report evaluated the key plant changes that occur during the mode changes so it is possible to identify the initiating events that can occur and systems available for event detection, actuation, and mitigation. It also considered initiating events and equipment available to mitigate those events. Based on that evaluation, Notes were proposed for several systems to prohibit the use of LCO 3.0.4.b.
These Notes were applied to LTOP, ECCS-Shutdown, AFW, and AC Sources - Operating.
TSTF-359-A also removed existing Notes from the ISTS and revised SR 3.0.4. There is no technical basis for concluding that the analysis performed in support of TSTF-359-A and the high-risk configurations addressed by the Notes are applicable to AP1000 plants. This is resolved by revising the disposition of TSTF-359-A as TSTF-359-A is deferred for future consideration.
- 4. (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.
Date report generated:
Monday, April 20, 2015 Page 9
GTST AP1000-P03-3.5.3, Rev. 1 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.
- 5. (Internal #304) APOG recommends making the editorial changes in the Actions section of the Bases, under heading A.1. These non-technical changes provide improved clarity, consistency, and operator usability. This is resolved by making the suggested changes and adding a comma after (ECCS) as follows:
A Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is consistent with times normally applied to an emergency core cooling system (ECCS), system which is capable of performing its safety function without a single failure.
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 10
GTST AP1000-P03-3.5.3, Rev. 1 IX. Evaluator Comments for Consideration in Finalizing Technical Specifications and Bases None Date report generated:
Monday, April 20, 2015 Page 11
GTST AP1000-P03-3.5.3, 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 (ML070660229).
- 5. 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 12
GTST AP1000-P03-3.5.3, 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 13
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact 3.5.3 3.5 PASSIVE CORE COOLING SYSTEM (PXS) 3.5.3 Core Makeup Tanks (CMTs) - Shutdown, Reactor Coolant System (RCS) Intact LCO 3.5.3 One CMT 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.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. Required CMT A.1 Restore required isolation 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> inoperable due to one valve to OPERABLE status.
outlet isolation valve inoperable.
B. Required CMT B.1 Restore water temperature 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> inoperable due to one or orand boron concentration more parameters (water to within limits.
temperature, or boron concentration) not within limits.
C. Required CMT C.1 Restore required CMT to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> inoperable for reasons OPERABLE status.
other than Condition A or B.
AP1000 STS 3.5.3-1 Amendment 0Rev. 0 Revision 19 Date report generated:
Monday, April 20, 2015 Page 14
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact 3.5.3 ACTIONS (continued)
CONDITION REQUIRED ACTION COMPLETION TIME D. Required Action and D.1 Initiate action to be in Immediately associated Completion MODE 5 with RCS Time not met. pressure boundary open and 20% pressurizer OR level.
LCO not met for reasons other than A, B, or C.
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 For the CMT required to be OPERABLE, the SRs of In accordance Specification 3.5.2, Core Makeup Tanks (CMTs) - with applicable Operating are applicable. SRs AP1000 STS 3.5.3-2 Amendment 0Rev. 0 Revision 19 Date report generated:
Monday, April 20, 2015 Page 15
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact B 3.5.3 B 3.5 PASSIVE CORE COOLING SYSTEM (PXS)
B 3.5.3 Core Makeup Tanks (CMTs) - Shutdown, Reactor Coolant System (RCS) Intact BASES BACKGROUND A description of the CMTs is provided in the Bases for LCO 3.5.2, Core Makeup Tanks - Operating.
APPLICABLE When the plant is shutdown with the Reactor Coolant System (RCS)
SAFETY pressure boundary intact, the CMT and Passive Residual Heat ANALYSES Removal (PRHR) are the preferred methods for mitigation of postulated events such as loss of normal decay heat removal capability (either loss of Startup Feedwater or loss of normal residual heat removal system).
The CMT and PRHR are preferred because the RCS pressure boundary can remain intact, thus preserving one of the barriers to fission product release. For these events, the PRHR provides the safety related heat removal path. And the CMT maintains RCS inventory control. These events can also be mitigated by In-containment Refueling Water Storage Tank (IRWST) injection; however, the RCS must be depressurized (vented) in order to facilitate IRWST injection.
Since no loss of coolant accidents (LOCAs) are postulated during MODES 5 and 6, the possibility of a break in the direct vessel injection line is not considered. As a result, only one CMT is required to be available to provide core cooling in response to postulated events. The two parallel CMT outlet isolation valves ensure that injection from one CMT occurs in the event of a single active failure.
CMTs satisfy Criterion 3 of 10 CFR 50.36(c)(2)(ii).
LCO This LCO establishes the minimum conditions necessary to ensure that one CMT will be available for RCS inventory control in the event of the loss of normal decay heat removal capability. The two CMT outlet isolation valves must be OPERABLE to ensure that at least one valve will operate, assuming that the other valve is disabled by a single active failure.
APPLICABILITY In MODE 4 without steam generator heat removal and in MODE 5 with the RCS pressure boundary intact, one CMT is required to provide borated water to the RCS in the event the nonsafety related chemical and volume control system makeup pumps are not available to provide RCS inventory control.
AP1000 STS B 3.5.3-1 Amendment 0Rev. 0 Revision 19 Date report generated:
Monday, April 20, 2015 Page 16
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact B 3.5.3 BASES APPLICABILITY (continued)
The CMT requirements in MODES 1, 2, 3, and 4 are specified in LCO 3.5.2, Core Makeup Tanks (CMTs) - Operating.
The CMTs are not required to be OPERABLE while in MODE 5 with the RCS open or in MODE 6 because the RCS is depressurized and borated water can be supplied from the IRWST, if needed.
ACTIONS A.1 With one outlet isolation valve inoperable action must be taken to restore the valve. In this Condition the CMT is capable of performing its safety function, provided a single failure of the remaining parallel isolation valve does not occur. A Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is consistent with times normally applied to an emergency core cooling system (ECCS),
system which is capable of performing its safety function without a single failure.
B.1 If the water temperature or boron concentration in the CMT is not within limits, it must be returned to within limits within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. With the temperature above the limit the makeup capability assumed in the safety analysis may not be available. With the boron concentration not within limits, the ability to maintain subcriticality may be degraded.
Because the mechanisms for significantly altering these parameters in the CMT are limited, it is probable that more than the required amount of boron and cooling capacity will be available to meet the conditions assumed in the safety analysis. Therefore, 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.
C.1 With the required CMT inoperable for reasons other than Condition A or B operation of the CMT may not be available. Action must be taken to restore the inoperable CMT to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. LOCAs are not postulated during the MODEs when this LCO is applicable. The only safety function is to provide LEAKAGE makeup in case normal RCS makeup is unavailable. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time is based on the availability of injection from the IRWST to provide RCS makeup. The ability of the IRWST to provide RCS injection is demonstrated by analysis AP1000 STS B 3.5.3-2 Amendment 0Rev. 0 Revision 19 Date report generated:
Monday, April 20, 2015 Page 17
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact B 3.5.3 BASES ACTIONS (continued) performed to show that IRWST injection together with ADS venting provides adequate core cooling. Such analysis was performed for the loss of RNS cooling during midloop operations. The analysis was performed in support of the AP1000 PRA (Ref. 2).
D.1 If the Required Action or associated Completion Time of Conditions A, B, or C are not met or the LCO is not met for reasons other than Conditions A through C, action must be initiated, immediately, to place the plant in a MODE where this LCO does not apply. Action must be initiated, immediately, to place the plant in MODE 5 with RCS pressure boundary open and 20% pressurizer level. In this condition, core cooling and RCS makeup are provided by IRWST injection and sump recirculation.
Opening of the ADS valves ensures that IRWST injection can occur.
SURVEILLANCE SR 3.5.3.1 REQUIREMENTS The LCO 3.5.2 Surveillance Requirements (SR 3.5.2.1 through 3.5.2.78) are applicable to the CMT required to be OPERABLE. The Frequencies associated with each specified SR are applicable. Refer to the corresponding Bases for LCO 3.5.2 for a discussion of each SR.
REFERENCES 1. FSAR Section 6.3, Passive Core Cooling System.
- 2. AP1000 PRA.
AP1000 STS B 3.5.3-3 Amendment 0Rev. 0 Revision 19 Date report generated:
Monday, April 20, 2015 Page 18
GTST AP1000-P03-3.5.3, 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 19
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact 3.5.3 3.5 PASSIVE CORE COOLING SYSTEM (PXS) 3.5.3 Core Makeup Tanks (CMTs) - Shutdown, Reactor Coolant System (RCS) Intact LCO 3.5.3 One CMT 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.
ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. Required CMT A.1 Restore required isolation 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> inoperable due to one valve to OPERABLE status.
outlet isolation valve inoperable.
B. Required CMT B.1 Restore water temperature 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> inoperable due to water and boron concentration to temperature or boron within limits.
concentration not within limits.
C. Required CMT C.1 Restore required CMT to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> inoperable for reasons OPERABLE status.
other than Condition A or B.
D. Required Action and D.1 Initiate action to be in Immediately associated Completion MODE 5 with RCS Time not met. pressure boundary open.
AP1000 STS 3.5.3-1 Rev. 0 Date report generated:
Monday, April 20, 2015 Page 20
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact 3.5.3 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.3.1 For the CMT required to be OPERABLE, the SRs of In accordance Specification 3.5.2, Core Makeup Tanks (CMTs) - with applicable Operating are applicable. SRs AP1000 STS 3.5.3-2 Rev. 0 Date report generated:
Monday, April 20, 2015 Page 21
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact B 3.5.3 B 3.5 PASSIVE CORE COOLING SYSTEM (PXS)
B 3.5.3 Core Makeup Tanks (CMTs) - Shutdown, Reactor Coolant System (RCS) Intact BASES BACKGROUND A description of the CMTs is provided in the Bases for LCO 3.5.2, Core Makeup Tanks - Operating.
APPLICABLE When the plant is shutdown with the Reactor Coolant System (RCS)
SAFETY pressure boundary intact, the CMT and Passive Residual Heat ANALYSES Removal (PRHR) are the preferred methods for mitigation of postulated events such as loss of normal decay heat removal capability (either loss of Startup Feedwater or loss of normal residual heat removal system).
The CMT and PRHR are preferred because the RCS pressure boundary can remain intact, thus preserving one of the barriers to fission product release. For these events, the PRHR provides the safety related heat removal path. And the CMT maintains RCS inventory control. These events can also be mitigated by In-containment Refueling Water Storage Tank (IRWST) injection; however, the RCS must be depressurized (vented) in order to facilitate IRWST injection.
Since no loss of coolant accidents (LOCAs) are postulated during MODES 5 and 6, the possibility of a break in the direct vessel injection line is not considered. As a result, only one CMT is required to be available to provide core cooling in response to postulated events. The two parallel CMT outlet isolation valves ensure that injection from one CMT occurs in the event of a single active failure.
CMTs satisfy Criterion 3 of 10 CFR 50.36(c)(2)(ii).
LCO This LCO establishes the minimum conditions necessary to ensure that one CMT will be available for RCS inventory control in the event of the loss of normal decay heat removal capability. The two CMT outlet isolation valves must be OPERABLE to ensure that at least one valve will operate, assuming that the other valve is disabled by a single active failure.
APPLICABILITY In MODE 4 without steam generator heat removal and in MODE 5 with the RCS pressure boundary intact, one CMT is required to provide borated water to the RCS in the event the nonsafety related chemical and volume control system makeup pumps are not available to provide RCS inventory control.
AP1000 STS B 3.5.3-1 Rev. 0 Date report generated:
Monday, April 20, 2015 Page 22
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact B 3.5.3 BASES APPLICABILITY (continued)
The CMT requirements in MODES 1, 2, 3, and 4 are specified in LCO 3.5.2, Core Makeup Tanks (CMTs) - Operating.
The CMTs are not required to be OPERABLE while in MODE 5 with the RCS open or in MODE 6 because the RCS is depressurized and borated water can be supplied from the IRWST, if needed.
ACTIONS A.1 With one outlet isolation valve inoperable action must be taken to restore the valve. In this Condition the CMT is capable of performing its safety function, provided a single failure of the remaining parallel isolation valve does not occur. A Completion Time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is consistent with times normally applied to an emergency core cooling system (ECCS), which is capable of performing its safety function without a single failure.
B.1 If the water temperature or boron concentration in the CMT is not within limits, it must be returned to within limits within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. With the temperature above the limit the makeup capability assumed in the safety analysis may not be available. With the boron concentration not within limits, the ability to maintain subcriticality may be degraded.
Because the mechanisms for significantly altering these parameters in the CMT are limited, it is probable that more than the required amount of boron and cooling capacity will be available to meet the conditions assumed in the safety analysis. Therefore, 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.
C.1 With the required CMT inoperable for reasons other than Condition A or B operation of the CMT may not be available. Action must be taken to restore the inoperable CMT to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. LOCAs are not postulated during the MODEs when this LCO is applicable. The only safety function is to provide LEAKAGE makeup in case normal RCS makeup is unavailable. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time is based on the availability of injection from the IRWST to provide RCS makeup. The ability of the IRWST to provide RCS injection is demonstrated by analysis performed to show that IRWST injection together with ADS venting AP1000 STS B 3.5.3-2 Rev. 0 Date report generated:
Monday, April 20, 2015 Page 23
GTST AP1000-P03-3.5.3, Rev. 1 CMTs - Shutdown, RCS Intact B 3.5.3 BASES ACTIONS (continued) provides adequate core cooling. Such analysis was performed for the loss of RNS cooling during midloop operations. The analysis was performed in support of the AP1000 PRA (Ref. 2).
D.1 If the Required Action or associated Completion Time of Conditions A, B, or C are not met action must be initiated, immediately, to place the plant in a MODE where this LCO does not apply. Action must be initiated, immediately, to place the plant in MODE 5 with RCS pressure boundary open. In this condition, core cooling and RCS makeup are provided by IRWST injection and sump recirculation. Opening of the ADS valves ensures that IRWST injection can occur.
SURVEILLANCE SR 3.5.3.1 REQUIREMENTS The LCO 3.5.2 Surveillance Requirements (SR 3.5.2.1 through 3.5.2.8) are applicable to the CMT required to be OPERABLE. The Frequencies associated with each specified SR are applicable. Refer to the corresponding Bases for LCO 3.5.2 for a discussion of each SR.
REFERENCES 1. FSAR Section 6.3, Passive Core Cooling System.
- 2. AP1000 PRA.
AP1000 STS B 3.5.3-3 Rev. 0 Date report generated:
Monday, April 20, 2015 Page 24