ML103060379

Response to Request for Additional Information, License Amendment Request, Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water Maintenance

ML103060379
Person / Time
Site:	Limerick
Issue date:	10/29/2010
From:	Cowan P Exelon Generation Co, Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME3551, TAC ME3552
Download: ML103060379 (58)

Text

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10 CFR 50.90 10 October 29,2010 29, 2010 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Limerick Generating Station, Units 1 1 and 2 Facility Operating License Nos. NPF-39 and NPF-85 NRC Docket Nos. 50-352 and 50-353

Subject:

Response to Request for Additional Information License Amendment Request Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water Maintenance

References:

1. Letter from Pamela B. Cowan (Exelon Generation Company, LLC) to U.S.

Commission, "License Nuclear Regulatory Commission, License Amendment Request, Proposed Specifications Sections 3.5.1,3.6.2.3,3.7.1.1, Changes to Technical Specifications 3.5.1, 3.6.2.3, 3.7.1.1, Times, dated March 19, 3.7.1.2 and 3.8.1.1 to Extend the Allowed Outage Times, II 19, 2010.

2. Letter from Peter Bamford, U.S. Nuclear Regulatory Commission Commission,, to Limerick Generating Station, Units 11 Michael J. Pacilio, Exelon Nuclear, "Limerick and 2 - Request for Additional Information Regarding Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water (RHRSW) Maintenance (TAC Nos. ME3551 And ME3552), dated September 21, 2010.

ME3552), II

3. Letter from Peter Bamford, U.S. Nuclear Regulatory Commission Commission,, to Limerick Generating Station, Units 11 Michael J. Pacilio, Exelon Nuclear, "Limerick and 2 - Request for Additional Information Regarding Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water (RHRSW) Maintenance (TAC Nos. ME3551 And ME3552), dated September 30, 2010.

ME3552), II In Reference 1, Exelon Generation Company, LLC (Exelon) requested changes to the Specifications (TS), Appendix A of Operating License Nos. NPF-39 and NPF-85 for Technical Specifications Limerick Generating Station (LGS), Units 1 1 and 2, respectively. The proposed changes would extend the TS allowed outage time (AOT)(ACT) for the Unit 11 and Unit 2 Suppression Pool Cooling (SPC) mode of the Residual Heat Removal (RHR) system, the Residual Heat Removal Service Water (RHRSW) system, the Emergency Service Water (ESW) system, and the A.C. Sources - -

Operating (Emergency Diesel Generators) from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to seven (7) days in order to allow for repairs of the RHRSW system piping.

Response to Request for Additional Information Docket Nos. 50-352 and 50-353 October 29, 29,2010 2010 Page 2 The NRC reviewed the license amendment request and identified the need for additional additional information in order to complete its evaluation of the amendment request. On On August 3, 3, 2010, 2010, draft questions were sent to Exelon to ensure that the questions were understandable, the the determine if the information was previously regulatory basis for the questions was clear, and to determine previously docketed The draft questions were discussed in a teleconference with the NRC docketed. NRC onon September September 9, 2010. In Reference 2, the NRC formally issued the request for additional information.

information. 1 to this letter provides a restatement of the questions along with Exelons Exelon's responses.

Upon further review of the license amendment request, the NRC again identified the need need for additional information in order to complete its evaluation of the amendment request. On September 28, 2010, draft questions were sent to Exelon to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine ifif the information was previously docketed. In Reference 3, the NRC formally issued the request for additional information. Attachment 2 to this letter provides a restatement of the questions along with Exelon's Exelons responses. to this letter provides revised proposed TS markups in response to the first request for additional information (Reference 2), which supersede in their entirety the proposed TS markups provided in the original submittal (Reference 1).

Exelon has concluded that the information provided in this response meets the intent of the original submittal (Reference 1) and does not impact the conclusions of the: 1) 1) Technical Analysis, 2) No Significant Hazards Consideration under the standards set forth in 10 CFR 50.92(c), or 3) Environmental Consideration as provided in the original submittal (Reference 1). 1).

This response to the requests for additional information contains revised regulatory commitments to implement the compensatory measures during the extended AOTs. The regulatory commitments were originally discussed in Section 4.2 of Attachment 11 of Reference regulatory revised based on the attached responses. These commitments are listed in 1, and are revised 1, and, where indicated, supersede the compensatory measures previously described in the original submittal (Reference 1).

IfIf you have any questions or require additional information, please contact Glenn Stewart at 610-765-5529.

II declare under penalty of perjury that the foregoing is true and correct. Executed on the 29th declare under day day of of October 2010.

2010.

Respectfully, Respectfully,

~ffi)arn-Pamela B.

Pamela owan B. eowan Licensing &

Director, Licensing Director, Regulatory Affairs

& Regulatory Company, Generation Company, LLC Exelon Generation Exelon LLC

Response to Request for Response for Additional Additional Information Information Nos. 50-352 Docket Nos. 50-352 and and 50-353 50-353 29,2010 October 29, 2010 Page 33 Page :1: Response toto Request Request for Additional Additional Information Information No.

NO.11 :2: Response to Request for Additional Information No.2 Information No. 2 3: Proposed Technical Specifications Revised Proposed Specifications Pages Pages : Summary of Regulatory Regulatory Commitments Commitments cc: Regional Administrator - NRC Region II

- wi attachments wI attachments NRC Senior Resident Inspector Inspector - Limerick Generating

- Generating Station Station I NRC Project Manager, NRR - Limerick Generating

- Generating Station Station Director, Bureau of Radiation Protection - Pennsylvania

- Pennsylvania Department Department of Environmental Protection

ATTACHMENT 1 1 License Amendment Request Limerick Generating Station, Units 1 1 and 22 Docket Nos. 50-352 and 50-353 Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water Maintenance No. 1 Response to Request for Additional Information No.1

Response to Request for Additional InformationInformation Attachment 11 Attachment Docket Nos. 50-352 and 50-353 Page 11 of Page of 21 21 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION INFORMATION NO. NO.11 PROPOSED TECHNICAL SPECIFICATION ALLOWED OUTAGE TIME TIME EXTENSIONS EXTENSIONS TO SUPPORT RESIDUAL HEAT REMOVAL SERVICE WATER MAINTENANCE MAINTENANCE In Reference 1, Exelon Generation Company, LLC (Exelon) requested changes to to the the Technical Technical Specifications (TS), Appendix A of Operating License Nos. NPF-39 and NPF-85 NPF-85 for Limerick Generating Station (LGS), Units 1 1 and 2, respectively. The proposed changes would extend extend the the TS allowed outage time (AOT) (ACT) for the Unit 1 1 and Unit 2 Suppression Pool Cooling (SPC) (SPC) mode mode of the Residual Heat Removal (RHR) system, the Residual Heat Removal Service Water (RHRSW) system, the Emergency Service Water (ESW) system, and the A.C. Sources Sources- -

Operating (Emergency Diesel Generators) from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to seven (7) days days in order to allow allow for repairs of the RHRSW system piping.

The NRC reviewed the license amendment request and identified the need for additional information in order to complete its evaluation of the amendment request. On August 3, 2010, draft questions were sent to Exelon to ensure that the questions were understandable, the regulatory basis for the questions was clear, and to determine if the information was previously docketed. The draft questions were discussed in a teleconference with the NRC on September 9, 2010. In Reference 2, the NRC formally issued the request for additional information.

9,2010. information. The questions are restated below along with Exelon's Exelons responses.

1. The NRC staff has identified the following issues with the format and content of the proposed TS changes contained in Attachment 2 of the LAR:

a. The footnotes extending the completion time (CT) are ambiguous in that each says the AOT ACT "may may be extended...for days...11 (added emphasis). This could extended.. .for up to a period of 7 days...

be interpreted as a 7-day extension of the 72-hour CT, for a 10-day total. The wording may be extended to 7 daysll IImay days is more explicit and the licensee is requested to revise the proposed TS changes accordingly.

Response

proposed TS markups have been revised to state IImay The proposed may be extended to 7 days days" as requested (see (see the revised TS markups provided in Attachment 3). Note that the revised TS markups provided in Attachment 3 supersede in their entirety the proposed TS markups provided in the original submittal (Reference 1).

b. The footnotes in each limiting condition for operation (LCO) action requirement identify b.

that the extended CT may be applied once per calendar year IIfor only, and for one unit only,1I also also specify the status of the opposite 1I unit.

"opposite unit. Since the TSs are unit-specific, the references to the references unit are vague. Since the actual frequency of use the other unit for each unit is once per once per 22 years, this should be be the stated frequency (Le., once every other calendar (i.e., 1I0nce ll ), and year),

year and the 1I0pposite unitll should refer to IlLimerick opposite unit Limerick Generating Station Unit X. X.II

Response to Request for Response for Additional lnformation Information Attachment 11 Attachment Docket Nos.

Docket Nos. 50-352 50-352 and and 50-353 50-353 Page 22 of Page of 21 21

Response

Response The proposed TS markup markup to TS TS LCO LCO 3.7.11, 3.7.1.1, Action Action a.3 a.3 has has been revised to been revised state once to state "once every other calendar year year" as requested.

requested. Note Note that that the proposed footnotes for the proposed the other for the other TS LCOs have been revised to reference the new new proposed proposed TS TS LCO 3.7.1.1 , Actions LCO 3.7.1.1, Actions a.3.a) or a.3.b). Therefore, this change is is no no longer necessary for longer necessary for the other proposed the other proposed TS LCO footnotes.

c. In the proposed TS changes, the reference to the compensatory measures refers to measures refers to the the NRC staffs safety evaluation authorizing this change. As this is As this is aa permanent change to permanent change to the TSs, it would be more appropriate to identify the compensatory measures measures in in the the TSs, and not in an external reference. The licensee is requested to delineate delineate in the TSs in the TSs the compensatory measures being credited, consistent with the risk evaluation, and evaluation, and include any appropriate surveillances for those measures. Further, several measures. Further, compensatory measures refer to the availability of TS equipment equipment covered by other LCOs (e.g., commitments 2b, 8a, and 8b). The TS change should specifically reference reference these LCOs being met without reliance upon any action requirement, rather than referring to non-TS commitments for availability of the same components already already covered by TS LCOs.

Response

Response The proposed footnote to TS LCO 3.7.1 .1 , Action a.3 has been converted to sub-3.7.1.1, Actions a) and b) under Action a.3, which include the compensatory measures credited in the risk evaluation for the proposed configuration for the planned RHRSW piping repairs. In particular, the compensatory measures credited in the risk evaluation, as specified in Section 4.2 of the original submittal (Reference 1), are the first part of compensatory measure 2 and compensatory measures 8a and 8b (see the revised proposed proposed TS markups provided in Attachment 3). Rather than creating new surveillances, these TS compensatory measures will be implemented through existing station procedures for protecting equipment and through a special procedure prepared to govern operations during the extended AOTs. ACTs.

As As described described in in the LAR, with one RHRSW return header disabled for piping replacement, the associated ESW loop will be aligned to the operable RHRSW return replacement, header such that header such ESW loops and one RHRSW loop would rely on the operable both ESW that both RHRSW RHRSW return header for aa flow path to the spray pond. The possibility of a single return header active active failure rendering the ESW failure rendering ESW System inoperable will be eliminated by de-energizing the the ESW ESW looploop return motor operated valves in their safe position. Although the isolation motor return isolation ESW system will ESW system will meet meet single active failure criteria in this alternate alignment, the ESW single active system system no no longer longer meets meets the of GDC intent of the intent GDC 44 for suitable redundancy and separation to impairment of prevent impairment prevent of safety function assuming a passive failure. For this reason, even safety function the ESW though the though ESW loop that is loop that not aligned to its normal RHRSW return header and the is not components cooled associated components associated cooled by by this ESW loop this ESW loop are covered by are covered by TS, they cannot be considered TS considered TS operable. Instead, they operable. Instead, will be they will administratively declared inoperable and be administratively action for TS action the TS the for aa single ESW loop single ESW would be inoperable would loop inoperable be entered. The ESW loop that is will, however, remain inoperable will, however, remain aligned for administratively inoperable administratively aligned automatic initiation and will for automatic capable of be capable be performing its of performing intended design its intended function.

design function.

Response to Request for Additional Information Information Attachment 11 Attachment Docket Nos. 50-352 and 50-353 Page 33 of Page of 21 21

d. The proposed change to add a fourth footnote to clarity clarify the applicability of of LCO LCO 3.5.1, 3.5.1, Emergency Core Cooling System, during hot shutdown conditions, conditions, isis worded differently differently than the other footnotes, in that: 1) made to the status

1) no reference is made status of of the the opposite opposite unit being shutdown with the reactor vessel head removed and the reactor cavity flooded; and 2) the compensatory measures are not identified. Although Although this footnote is is intended to clarify applicability (see request number 11.1 discussion regarding

.f for further discussion this footnote) and does not extend a CT, these two omissions could have have been included.

The licensee should submit a revised specification for this footnote or explain explain why these these two conditions should not specifically be applied to LCO 3.5.1. Alternatively, the licensee may provide a direct reference to LCO 3.7.1.1 for this and other supported system TS actions.

Response

The proposed footnote to TS LCO 3.5.1 is no longer considered necessary and is hereby withdrawn from this license amendment request (see the response to Item 11.1 .f below).

repairs of one RHRSW subsystem piping.

e. The footnotes specifically address "repairs piping. This II would preclude the applicability of the extended CT for ESW system piping repairs, even though the amendment request identifies ESW as a system that is experiencing piping corrosion. The licensee is requested to confirm its understanding of the scope of system piping repairs permitted by this proposed change.

Response

The license amendment request only supports repairs to the RHRSW subsystem piping that is common to both units and is unisolable. ESW piping can be unitized and isolated from the non-outage unit for repairs. In this configuration, ESW piping repairs can be performed under existing TS requirements during outage conditions. Therefore, this LAR is limited to repairs to the RHRSW subsystem piping.

f. The marked up TS pages contained in Attachment 2 of the LAR, Insert A, states that one of the two remaining LPCI [low-pressure coolant injection] subsystems may be "one inoperable in that it is aligned in the shutdown cooling mode... Insert inoperable II Insert A does not direct any ACTIONS that any that may be derived from this note. Thus, as constructed, and under the conditions specified, the ACTIONS for the two remaining LPCI subsystems would have conditions to be applied with the one subsystem lined up for shutdown cooling declared inoperable (3 subsystems total inoperable). If the intent of the note is to not require taking the (3

subsystem inoperable, it must be re-worked. The required for the third sUbsystem ACTIONS required approach taken in NUREG-1433, Standard Technical Specifications [Boiling Water Reactor] BWR/4, may be helpful in determining a proper construction.

Reactor]

Response

The footnote The LCO 3.5.1 was intended to support a possible unplanned shutdown footnote to TS LCO of the operating unit, which would require the unit to be taken to the cold shutdown of

Response to to Request Request for Additional Additional Information Information Attachment 11 Attachment Docket Nos.

Docket Nos. 50-352 50-352 and and 50-353 50-353 Page 44 of Page of 21 21 performing the condition while performing the RHRSW RHRSW subsystem subsystem pipingpiping repairs.

repairs. UponUpon further further evaluation, it has has been been determined determined that that under under this this circumstance, circumstance, existing existing TS TS requirements would would be be followed as as required.

required. Therefore, Therefore, Exelon Exelon has determined that has determined that the the proposed footnote to TS TS LCO LCO 3.5.1 3.5.1 is is not not necessary necessary and and hereby hereby withdraws withdraws the the proposed change to TS LCO LCO 33.5.15 1 from this this license license amendment amendment requestrequest. As As aa result, result, the TS page showingshowing the the proposed proposed changechange to to TSTS LCO LCO 33.5.1 no longer is no 5 1 is included with longer included with the revised proposed TS markups markups (refer(refer to to Attachment Attachment 33 for for the the revised proposed TS revised proposed TS markups).

2. In the LAR, Table 4-1 of Attachment 3 identifies plant changes not incorporated into not incorporated into the the probabilistic risk assessment (PRA) model and provides disposition of provides a disposition of these these items items as as to to their impact on the application. Four changes are identified (LG2007-048, LG2007-049, LG2007-049, LG2008-009, and LG2009-001) as deferred and not yet implemented, implemented, and and the disposition is the disposition is "no no impact, impact, based on the changes not yet being implemented II implemented. The licensee does not licensee does not identify the risk impact on the TS change risk analyses once the plant changes are are implemented. The licensee is requested to provide its disposition disposition of the potential impact of each planned modification on the risk results supporting this proposed permanent permanent TS change.

Response

The status of each of the items is provided below.

LG2007-048 and LG2007-049: The proposed changes associated with these two modifications have been subsequently cancelled. Therefore, there is no impact on the risk assessment.

LG2008-009:

LG2008-009: These Engineering Change Requests (ECRs) were identified as contingencies that have subsequently been voided or completed without the change being contingencies installed installed as the contingencies were determined not to be needed. Therefore, there is no impact impact on the risk assessment.

LG2009-001:

LG2009-001: The impact impact of the modification of the Standby Liquid Control System (SLCS)

"C" C pump from automatic to manual start can be bounded by assuming that the "C" pump from C SLCS pump pump fails fails to to start.

start. A sensitivity case A sensitivity run indicates case run indicates that this has a very minimal impact (Le., (i.e.,

-2E-9 2E-9 onon the calculated CDF the calculated CDF values) and no impact (Le., (i.e., -0.0 0.0 delta CDF) on the risk assessment assessment results presented in results presented in Attachment 3 of the original LAR (Reference 1).

Therefore, Therefore, there there is is no impact on the risk assessment.

no impact

3. In the

3. In LAR, Table the LAR, Table 4-24-2 of Attachment identifies that supporting requirement SY-A12b from Attachment 33 identifies the PRA standard the PRA standard is is not met, and not met, identifies that a detailed investigation for flow diversion and identifies pathways pathways has has notnot been performed but been performed would have but would have a livery very limited impact. The licensee is limited impact."

requested requested to to provide provide its its basis basis asas to why this to why this technical technical issue has a very limited impact. In issue has addition, please addition, address how please address flow diversion how flow pathways were considered for the RHRSW and diversion pathways systems for ESW systems ESW for this application; ifif such this application; pathways exist such pathways exist and not modeled, are not and are modeled, then then a study or sensitivity study sensitivity or other disposition of other disposition of the the impact impact on on the risk analyses the risk analyses needsneeds to to be provided.

Response to Request for Additional Response Additional Information Information Attachment 11 Attachment Docket Nos.

Docket Nos. 50-352 50-352 and and 50-353 50-353 Page 55 of Page of 21 21

Response

Response The intent of the statement in Table 4-2 4-2 of of Attachment 33 was was that that the the supporting supporting requirement may not be met since aa detailed detailed analysis analysis for flowflow diversion diversion pathways for all pathways for all modeled systems was not not performed but but rather were incorporated into were incorporated into the system models the system models based on a generic assumption (i.e., (I.e., flow diversions diversions for lowlow pressure systems are pressure systems are not not modeled if the nominal pipe diameter of the flow diversion diversion line line is is less than or less than equal to or equal 1/3 of to 1/3 of the nominal diameter of the required flow path path line).

line). However, However, severalseveral flow flow diversion diversion pathways are included in the PRA model. For example, example, thethe RHRSW system logic modeling system logic modeling includes backflow through the alternate pump flow path in the same loop via aa failed check same loop check valve, and the ESW system logic modeling includes backflow through the service the water service water system via a failed boundary check valve.

In general, however, flow diversion pathways would represent a small impact impact on the overall system unreliability because they would require a failure to close of a boundary valve valve or valves, or a spurious operation of a normally closed valve. These failure modes would would typically be low contributors to the overall system unreliability and would potentially potentially be be candidates for exclusion from the PRA model via supporting requirement SY-A15 SY-A15 from the combined ASMEIANS ASME/ANS PRA Standard (Reference 3).

Since flow diversion pathways are included for ESW and RHRSW (and many other systems), and since these failure modes otherwise represent small contributions to system unreliability, the conclusion is that there is a very limited impact on the results for this application.

Additionally, as noted in response to RAI #4 below, the potential impact from inadvertent flow diversions in the form of pre-initiator misalignment errors is also minimized as compensatory compensatory measures are included to ensure proper alignment of the ESW and RHRSW systems prior to entering the AOT ACT configuration.

4.

4. In In the the LAR, LAR, Table 4-2 of Attachment 3 identifies that supporting requirement HR-A1 HR-Al is not met met since aa formal review of plant maintenance and testing procedures formal review and practices was not not done identify potential pre-initiator alignment errors. The impact is identified as "no done to identify no impact" impact since since the pre-initiator errors in the PRA model include those for specific systems the pre-initiator identified identified as as most relevant to this application. However, neither the RHRSW nor ESW most relevant systems systems are included in are included the scope of the pre-initiator events included in the PRA model. The in the licensee licensee isis requested requested to justify not pre-initiator alignment errors for these systems not including pre-initiator in the PRA in the PRA model, model, or or disposition impact of such errors.

disposition the impact

Response

Response An RHRSW An system pre-initiator RHRSW system is included pre-initiator is in the included in the model (and is model (and is referred RHR referred to as an "RHR pre-initiator in loop pre-initiator loop" 4-2 of Table 4-2 in Table Attachment 33 in of Attachment in the the LAR).

LAR). The risk assessment results identified this pre-initiator identified this pre-initiator (refer discussions associated with basic event JHUMNA(B)DMI to discussions (refer to in Appendix in Appendix BB of Attachment 33 in of Attachment in the LAR) as the LAR) as anan important important contributor to the overall results.

This pre-initiator This represents the pre-initiator represents potential that the potential the normally that the normally open 12-ll52A valve is RHRSW 12-1152A open RHRSW

Response to Request for Additional Information Attachment 11 Docket Nos. 50-352 and 50-353 Page 66 of 21 not left in its normally open position, goes undetected, and renders the loop failed when the RHRSW pumps are started.

Based on this insight, compensatory measure #2 in the LAR was identified to ensure that the available RHRSW loop valves are in proper position prior to entering the ACT AOT configuration.

configuration Additionally, compensatory measure #8 in an the LAR wall will ensure that the ESW valves are also in proper alignment prior to entering the ACTAOT configuration. The special procedure that will be created for entry into the ACTAOT configuration will ensure that both the RHRSW and ESW systems are in proper alignment. These compensatory measures will virtually eliminate potential pre-initiator failure modes from occurring for these systems, thereby minimizing the potential risk from pre-initiators.

5. In the LAR, Table 4-2 of Attachment 3 identifies that supporting requirements DA-C6 and DA-C7 are not met for the use of actual plant data and practices in compiling component demand data, but identifies a minimal impact in that the values used in the PRA are a "reasonable plant. II The data reasonable representation of the best estimate reliability response of the plant.

maintenance rule database,"

source is only identified as the "maintenance database, but there is no discussion of how this data is collected. The licensee needs to provide its basis for concluding that the data used to determine component demands and the number of surveillance tests and maintenance activities reasonably reflect the as-operated plant.

Response

The Maintenance Rule database contains the data collected to satisfy the requirements of 10 CFR 50.65(a)(2). The data is collected consistent with the scope of the maintenance rule functions and with the degree of rigor required to comply with the performance monitoring requirements of that program. The information in the database was used to provide a first order estimate of the demands and run-times for all of the plant-specific data utilized in the PRA model. These demand estimates reflect the actual plant practices and as such reasonably reflect the as-operated plant. The shortcoming with respect to the DA DA-C6 requirements is that the documentation for the demand estimate determination could be better, but this would not impact the PRA model results.

The DA-C7 requirement is to base the "number" number of tests, maintenance activities, and unplanned maintenance on actual plant performance. Maintenance Rule data collection efforts are utilized to determine the total unavailability values used in the PRA model for risk significant systems. This data is collected for actual accrued unavailability hours due to any reason, but is not based on "number" number of tests, maintenance activities, and unplanned maintenance as this is not necessary with the approach that is taken. Therefore, although not specifically tied to these parameters as may be required to meet the intent of the DA-C7 supporting requirement, this unavailability data reasonably reflects the as-operated plant.

6. In the LAR, Section A.3.1 of Attachment 3 discusses the technical aspects of the fire PRA model. The fire PRA is characterized as an update of the Individual Plant Examination of External Events and specifically identifies plant areas that are modeled (Main Control Room, Auxiliary Equipment Room, Turbine Building), unit-specific models, cable data for control

Response to Request for Additional Information Attachment 11 Docket Nos. 50-352 and 50-353 Page 77 of 21 rod drive system, and completion of specific tasks from NUREG/CR-6850, Fire "Fire PRA Facilities. The staff requests additional information to Methodology for Nuclear Power Facilities."

understand how the scope and technical adequacy of this model supports the requested TS change risk evaluation:

a. The Main Control Room, Auxiliary Equipment Room, and Turbine Building compartments are specifically identified as "refined refined analyses" "integrated into the analyses and integrated results.II It is not clear then how other plant areas are being treated in the fire fire PRA results.

PRA. If other areas are screened from consideration or conservatively modeled, do these areas include plant equipment (including required cables) that is relied upon during the RHRSW outage, such that the prior screening could be invalidated, or the conservative treatment could be masking the change in risk for the RHRSW outage configuration? The licensee is requested to better describe the scope of the fire PRA model for the plant areas modeled, and if appropriate, provide additional risk analysis for fire areas previously screened or conservatively modeled for this application.

Response

The fire PRA model utilized for the assessment includes a full scope representation from the risk of fire for over 100 fire compartments and the yard area. The selection of the global plant analysis boundary and the criteria for including/excluding plant areas are consistent with the current NUREG/CR-6850 guidance and methods. Additionally, no fire compartments (physical analysis units) were screened from final quantification in the fire PRA. Therefore, the scope of areas included is sufficient for this application.

b. Several areas of conservatism in the fire PRA model are identified. If a fire area is conservatively treated in the baseline model, then this may mask the change in risk for an application such as the RHRSW outage evaluation. For the delta-risk calculation, has an evaluation of the impact of the conservative treatments been made, and what are the conclusions of that evaluation? The licensee needs to demonstrate that model conservatism is not masking the fire risk impacts associated with the RHRSW outage evaluation. In addition, specifically address multiple spurious operations, instrumentation, iterations, and multi-compartment modeling assumptions for this specific application.

Response

For the delta risk evaluation, a specific analysis regarding the impact of potential conservatisms has not been performed. However, any potential masking from conservative treatments can be no larger than the calculated base fire CDF. Therefore, the maximum numerical impact on the delta risk assessment can be clearly bounded by assuming that conservative treatments would eliminate an amount equal to the base fire CDF in the delta risk evaluations. Revisions to portions of Table 3.3-1 from Attachment 3 of the LAR are shown to illustrate the potential bounding impact.

Response to Request for Additional Information Attachment 11 Attachment Docket Nos. 50-352 50*352 and 50-353 50*353 Page 88 of Page of 21 21 FIRE PRA INPUT PARAMETERS FOR BOUNDING CASE CASE ASSESSMENT OF POTENTIAL IMPACT OF MASKING MASKING FROM CONSERVATISMS ON ON THE CALCULATED DELTA-RISK ORIGINAL VALUES FROM LAR SHOWN (ORIGINAL SHOWN IN PARENTHESIS)

PARENTHESIS Input Parameter Unit 11 Value Unit Unit 22 Value Value FCDF FCDFBASE sASE 1.30E-OS/yr 1 .30E-O5Iyr (1(1.30E-S/yr)

.30E-5/yr) .43E-05/yr (1 11.43E-OS/yr .43E-05/yr)

(1.43E*OS/yr)

FCDF FCDFAA 5.29E-05/yr (3.99E-O5Iyr)

S.29E-OS/yr (3.99E-OS/yr) 5.96E-O5Iyr S.96E-OS/yr (4.53E-05/yr)

(4.S3E-OS/yr)

FCDF FCDFBs E-05/yr (8.11 E-05/yr) 9.41 E-OS/yr E-OS/yr) 8.82E-05/yr 8.82E-OS/yr (7.39E-05/yr)

(7.39E-OS/yr)

As can be seen, this bounding case leads to only about a 30% 300/0 increase increase in the the calculated calculated fire CDFs for the A loop cases and to less than a 20% 20% increase in the calculated fire CDF5 for the B loop cases. When this bounding assumption is taken further to compare CDFs to the acceptance guidelines, there is a similar small impact as shown in the revisions to portions of Tables 3.4-1 and 3.4-2 from Attachment 3 of the LAR. That is, the net results indicate that the proposed configuration is still at or near that region of the acceptance guidelines such that compensatory measures are warranted. Appropriate compensatory measures have already been identified to minimize the overall risk associated with the configuration such the conclusions from the risk assessment would not be altered by the potential impact from making this bounding assumption.

COMPARISON OF RESULTS TO ACCEPTANCE GUIDELINES FOR BOUNDING CASE ASSESSMENT OF POTENTIAL IMPACT OF MASKING FROM CONSERVATISMS (ORIGINAL VALUES FROM LAR SHOWN IN PARENTHESIS)

Figure of Value Acceptance Guideline Below Acceptance Merit Merit Guideline Total Unit 11 Values iCDF ilCDF (1 .03E-O6Iyr) 1 .29E-06/yr (1.03E-06/yr) 1.29E-06/yr <1 .OE-06/yr for

<1.0E-06/yr Region III, Ill, Barely above Region

<1 .OE-O5Iyr for

<1.0E-OS/yr Region II Ill in Region II III (Barely above Region Ill in Region II)

III ICCDP ICCDPAA (5.92E-07) 8.41 E-07 (S.92E-07) <1 .OE-06, or <1.0E-S(1)

<1.0E-06, <1 .0E-5 Yes (Yes)

ICCDP ICCDPBs 1.64E-06 (1 .39E-06) 1 .64E-06 (1.39E-06) <1.0E-06, <1 .OE-&

<1 .OE-06, or <1.0E-S(1) 1 Yes (Yes)

Total Unit Total Unit 2 Values ACDF ilCDF 1 .27E-06/yr (9.88E-07/yr) 1.27E-06/yr (9.88E-O7Iyr) <1.0E-06/yr for Region III,

<1 .OE-06/yr for Ill, Barely above Region

<1 .OE-O5Iyr for Region II

<1.0E-OS/yr Ill in Region II III (Just Below Region II in Region III)

Ill)

Response to Request for Additional Information Attachment 11 Attachment Docket Nos. 50-352 and 50-353 Page of 21 Page 99 of 21 COMPARISON OF RESULTS TO ACCEPTANCE GUIDELINES FOR FOR BOUNDING BOUNDING CASE ASSESSMENT OF POTENTIAL IMPACT OF OF MASKING FROM CONSERVATISMS CONSERVATISMS (ORIGINAL VALUES FROM LAR SHOWN IN IN PARENTHESIS)

PARENTHESIS)

Figure of Value Acceptance Guideline Below Acceptance Below Acceptance Merit Guideline Guideline tCCOPA ICCDPA 9,46E-07 9.46E-07 (6.72E-07) <1.0E-06, <1.0E-S(1)

<1.OE-06, or <1.OE-& Yes (Yes)

(Yes)

ICCOP ICCDPBB 1.S0E-06 (1 .22E-06) 1 .50E-06 (1.22E-06) <1.0E-06,

<1 <1.0E-S(1)

.OE-06, or <1 .0E-5 Yes (Yes)

(1) Per NUMARC 93-01 as endorsed by RG 1.182, 1.182, a value between 1E-06, but less 1E-06, but less 1 E-05 may be deemed acceptable with effective compensatory measures than 1E-05 measures implemented to reduce the sources of increased risk.

Consistent with the LAR evaluation, even with considering the potential bounding impact that masking conservatisms may have on the delta risk assessment, it is demonstrated demonstrated with reasonable assurance that the proposed TS change is within the current risk acceptance guidelines (Le., Ill or barely in Region II) in RG 1.174 (i.e., in Region III 1.174 and not substantially above the acceptance guidelines in RG 1.177 1.177 for permanent changes.

This combined with effective compensatory measures to maintain lower risk ensures that the TS change meets the intent of the ICCDP and ICLERP acceptance guidelines of 1.0E-05 1 .OE-06 established for compatibility with the ICDP and ILERP limits of 1 .OE-05 and 1.0E-06 Section 11 in NUMARC 93-01, which is applicable for voluntary maintenance activities requiring risk management actions.

As for the additional items to address (multiple spurious operations, instrumentation, iterations, and multi-compartment modeling assumptions), these were noted in the submittal as items not yet incorporated into the current fire PRA model. There are some conservative elements identified and some non-conservative elements identified. In general, these items should not detract from the insights obtained from the use of the existing fire PRA model. As such, the compensatory measures that have been identified will help to minimize the overall risk associated with the configuration such that the conclusions from the risk assessment would not be altered by the potential impact that maymay arise from these other assessments. In addition, each of the elements is discussed more fully below.

discussed spurious operations: Limerick is addressing multiple spurious operations in Multiple spurious Multiple accordance with the NEI 00-01 (Reference 4). As part of this process, an expert panel accordance conducted in 2009 to disposition the generic BWR MSO scenarios and identify was conducted additional site specific MSOs. MSOs of concern have been entered into the corrective additional program and will be evaluated to determine their impact on fire safe shutdown.

action program action issues will be handled with the development of hardware changes or the Open issues Open establishment of additional viable operator manual actions such that all of the fire safe establishment requirements will be maintained. This approach combined with the low shutdown requirements shutdown likelihood of likelihood MSOs ensures that the lack of current detailed modeling of MSOs will have of MSOs

Response to Request for Additional Information Attachment 11 Attachment Docket Nos. 50-352 and 50-353 Page 10 Page of 21 10 of 21 a negligible impact on the fire PRA model, and especially on the delta delta risk risk assessment assessment provided in the LAR.

Instrumentation: The instrumentation available to the operators at at Limerick isis highly highly redundant, diverse, and reliable. The fire safe shutdown program program at Limerick ensures at Limerick ensures that there is at least one train of instrumentation free of fire damage damage for any area to any fire area to support fire safe shutdown. Additionally, procedures (i.e., (Le., Fire Safe Shutdown Guides) Guides) exist that indicate what instruments can be trusted for fires in a given area. Therefore, Therefore, the lack of detailed modeling of all required instrumentation will have aa negligible impact impact on the fire PRA model, and especially on the delta risk assessment provided in in the LAR.

LAR.

Iterations: This was noted as a potential conservatism since the current Limerick fire PRA model has undergone limited iterations for scenario refinement. As such, such, the potential impact of this conservatism is bounded by the analysis described described above.

Multi-compartment analysis: The design and plant layout of Limerick makes fire propagation to multiple compartments unlikely compared to the tire fire risk in individual compartments. Additionally, the identification of the important fire areas from the delta risk assessment in the LAR would not be altered by the incorporation of a detailed multi- multi-compartment analysis into the fire PRA model. This, combined with the general high high reliability of existing barriers (e.g., penetration seals and tirefire doors), ensures that the lack of current detailed multi-compartment analysis will have a negligible impact on the fire PRA model, and especially on the delta risk assessment provided in the LAR.

7. The calculated incremental conditional core damage probability (ICCDP) for internal tires fires for train A and train B differ for each unit by more than a factor of two, with train B being more significant in each unit. This effect is present in the internal events core damage frequency, but to a lesser degree. In addition, the unit-specific risk calculations are not identical for but internal events for a train A outage, but are the same for train B, and the fire ICCDPs are different for each unit. Internal events large early release frequency values are also different between the two units. No explanation is provided for these asymmetries. The licensee is requested to explain the unit and train differences in the risk metrics in terms of actual plant requested differences or PRA modeling assumptions, and identify any insights obtained from these differences.

Response

Response associated with the A train and B train are different based on the different fire ICCDPs associated The ICCDPs CDF contributions delineated in Tables A-6 through A-9 of Attachment 3 of the LAR CDF contributions submittal.

submittal. ForFor both units, a fire in the Division 11 switchgear area (Le., IEFR-01 3-B/C for Unit (i.e., IEFR-013-B/C IEFR-01 Table A-7 and IEFR-019-B/C 11 in Table 9-B/C for Unit 2 in Table A-9) results in failures of Division 11 and Division equipment due to cable routing. Similar scenarios exist for fires in the Division 2 Division 33 equipment switchgear (i.e., IEFR-015-B/C areas (Le.,

switchgear areas IEFR-01 7-B/C for Unit 2 in IEFR-01 5-B/C for Unit 11 in Table A-6 and IEFR-017-B/C A-8) which Table A-B)

Table which result inin failures of Division 2 and Division 4 equipment due to cable However, the impact from the Division 11 and Division 3 failures has more of an routing. However, routing.

impact on impact the CDF on the CDF inin the BB loop loop cases since the SRVs require DC power from Division 11 or in both Division 33 in Division units. With no AC power available from these divisions to provide power both units.

Response to Request for Additional Information Attachment 11 Docket Nos. 50-352 and 50-353 Page 1111 of Page of 21 21 to the chargers (based on the postulated fire scenario failures), RPV depressurization depressurization capabilities are not available from the SRVs following battery depletion depletion. As such, there are fewer overall success paths available when the RHRSW B B loop is out of service given given failures of both the Division 11 and Division 3 equipment compared to the RHRSW A loop loop case which still has RPV depressurization capabilities available via the SRVs in the corresponding postulated fire scenario that fails the Division 2 and Division 4 equipment.

The asymmetry described above is the major reason that the B B loop case results in a higher CDF value than the A loop case. However, there is one additional asymmetry associated with the fire PRA that also leads to higher results when the B loop is out of service compared to the A loop. This asymmetry is described in Section A.3.2 of Attachment 3 of the LAR submittal and relates to the treatment of the fires initiating in the Remote Shutdown Room Because of this asymmetrical treatment, a Remote Shutdown Room severe fire Room.

contributes a larger amount in the B loop case compared to the A loop case for both units. units.

This can be noted via the inclusion of scenario IEFR-26-C as a significant contributor in the B loop cases, but not in the A loop cases in Tables A-6 through A-9 of Attachment 3 of the LAR submittal.

Similarly, the asymmetries related to Division 1 1 and 3 failures compared to Division 2 and 4 failures are also responsible for the higher internal events CDF values calculated for the B B loop cases as compared to the A loop cases (as reported in Table 3.2-1 of Attachment 3 of the LAR submittal), but as noted the impact is to a lesser degree in the internal events model results than in the fire model results. Additionally, Section A.1 of Attachment 3 of the LAR submittal also provided a description of the internal events results for the A and B loop Bloop cases based on the risk contribution by functional sequence for both units. The most notable asymmetry described there is related to the fact that alternate injection from RHRSW goes through the RHR B loop in Unit 1, but through the RHR A loop in Unit 2. This does not have much of an impact on the overall CDF results, but does have an impact on the LOCA initiated sequences and more importantly the containment bypass sequences due to ISLOCA scenarios. This difference in the contribution from the ISLOCA scenarios results in the difference in the LERF results as reported in Tables 3.2-1 and 3.2-2 of Attachment 3 of the LAR submittal.

The results of both the internal events model results and the fire PRA model results were fully utilized to provide insights into the identification of the proposed compensatory measures that were included in the LAR submittal. From the internal events model, this included a detailed assessment as described in Appendix B of Attachment 3 of the LAR submittal. From the fire PRA model results, this included the identification of the important fire areas that specifically account for the asymmetries described above. Namely, the appropriate switchgear areas with elevated risks for the different configurations are clearly identified and the Remote Shutdown Room area is identified as a fire area of potential elevated risk when the B loop is out of service. This insight was also extended to the identified compensatory action number 6 where it was recommended that during the A loop outage, a briefing be performed highlighting the fact that some of the normally operated equipment from the remote shutdown panel will not be available (and remote operation of the B loop equipment may be required).

Response to Request for Additional Information Information Attachment 11 Attachment Docket Nos. 50-352 and 50-353 Page 12 Page of 21 12 of 21

8. The compensatory measures, which are referenced as the tier 22 evaluation for for key principle principle 4 of RG 1.177, identified in Section 4.2 of the LAR, Attachment 1, 1, are vague and and require clarification as to exactly what the commitment involves:

a. Commitment #1 identifies that adequate staffing ll will be maintained lIadequate staffing maintained onsite to respond respond to lIunexpected unexpected conditions.

conditions.II The staff does notnot understand understand the scope and and meaning meaning of of these terms. For example, it [is] unclear how adequate staffing ll will be lIadequate staffing be determined determined and and validated and what this commitment means in terms of numbers and disciplines disciplines of of personnel.

Response

Staffing is governed by the normal work control process for outage conditions under under which the RHRSW piping repairs would be performed and also for any unexpected emergent conditions. Therefore, ensuring adequate staffing in response to unexpected conditions is no longer considered a regulatory commitment and has been deleted. deleted.

electivell maintenance and discretionary

b. Commitment #2 identifies lIelective IIdiscretionaryll maintenance, as well as IItesting. 1I testing. The staff does not understand the scope of the two terms, and is is unclear as to whether the commitment refers to all testing, or only elective lIelective ll or IIdiscretionaryll discretionary testing.

Response

Elective maintenance and discretionary maintenance are general terms that are defined WC-AA-106 in more detail in procedure WC-AA-1 06 as elective maintenance non-degraded and elective maintenance degraded, respectively. In general, elective maintenance involves enhancements to equipment that is fully capable of meeting its intended design function or performance criteria. Discretionary maintenance is maintenance on degraded but operable equipment, which involves engineering judgment as to the effect of the degradation, the scope of repairs necessary and the timing for the repairs. Testing refers to surveillance testing required by Technical Specifications, the Technical Inspection/Testing, etc., to verify that equipment is Requirements Manual, Inservice InspectionlTesting, capable of performing its intended design function. These maintenance and testing activities will be prohibited by considering the affected systems as protected as defined in procedure OP-AA-1 08-117. The list of protected equipment will be controlled as part of the special procedure developed specifically to govern plant operation while in the ACTs.

extended AOTs.

c. Subpart (a) Commitment #2 states that the proper standby alignment of RHRSW will be ensured. The staff does not understand how this will be accomplished (e.g., by lIensured.1I alignment verification, by performance of surveillance test, by flow testing).

Response

The RHRSW The RHRSW and ESW System alignments required to minimize the impact to plant safety during the extended AOTs safety ACTs will be established prior to entry into the work window periodically verified during the work window in accordance with a check-off list and periodically and

Response to Request for Additional Information Attachment 11 Attachment Docket Nos. 50-352 and 50-353 Page 13 Page of 21 13 of 21 contained in the special procedure developed specifically to govern plant operation while govern plant in the extended ACTs.

AOTs.

Additionally, flow balance verification testing will be performed in in advance advance of of the the extended AOT for each RHRSW subsystem to demonstrate demonstrate acceptable cooling cooling water flow rates are maintained for all ESW system cooled equipment when the the flow from both both ESW loops is returned through one RHRSW return header. This flow test is is aa one-time one-time test for each RHRSW subsystem, and is separate from the system alignment verification described above, but will be performed initially and once per 10 10 years thereafter, if required, to support future RHRSW piping repairs beyond the current plan of two refueling outages per unit. Completion of this flow balance verification testing will be a pre-requisite of the special procedure.

d. The staff also notes that Commitment #2 is poorly structured in that it puts some commitments in the opening paragraph, and others as detailed subparts (a) and (b).

The licensee is requested to revise the structure of this commitment.

Response

The first part of compensatory measure #2 has been incorporated into the revised proposed TS markup for TS LCO LCC 3.7.1.1, Action a.3 (see Attachment 3), and therefore, is no longer considered a regulatory commitment but a required action while in the TS LCO 3.7.1.1. The remaining portions of compensatory measure #2 have been revised as shown below and will be incorporated into the special procedure developed AOTs. The second action specifically to govern plant operation while in the extended ACTs.

has also been modified in content for consistency with the new proposed TS LCO 3.7.1.1, Actions a.3.a) and a.3.b).

1. The following action will be taken prior to entry into the proposed configuration:

• Proper standby alignment of the operable RHRSW subsystem will be ACT to reduce the contribution from potential ensured prior to entry into the AOT pre-initiator errors.

2. Also, the following actions will be taken prior to entry into the proposed configuration:

• • When the RHRSW subsystem A is inoperable to allow for repairs of the RHRSW A subsystem piping with Limerick Generating Station Unit 2 RHRSW shutdown, reactor vessel head removed and reactor cavity flooded, the shutdown, following equipment will be verified as available and protected as defined in OP-AA-1 08-117:

procedure OP-AA-108-117:

o ESW loop A o Unit 11 LPCI subsystems A and C Unit o D11, Di 3, and D23 4kV buses and emergency diesel generators Dli, D13, o Unit 11 Division 11 and Division 3 Safeguard DC Unit

Request for Additional Information Response to Request Information Attachment 11 Attachment Docket Nos.

Docket Nos. 50-352 50*352 andand 50-353 50*353 Page 14 Page 14 of of 21 21

• When the the RHRSW subsystemsubsystem A A is inoperable to is inoperable allow for to allow repairs of for repairs of the the RHRSW A A subsystem sUbsystem piping piping with with Limerick Generating Station Limerick Generating Unit 11 Station Unit shutdown, reactor vessel shutdown, vessel headhead removed removed and and reactor reactor cavity cavity flooded, flooded, thethe following equipment equipment will be be verified verified as as available available and and protected protected as defined in as defined in OP*AA-108*117:

procedure OP-AA-1 08-117:

oo ESW looploop A A o Unit Unit 2 LPCI subsystems A subsystems A and and C C

o 011, D21, Dli, 021, and D23 023 4kV buses buses and and emergency diesel generators emergency diesel generators o Unit 2 Division 11 and Division 33 Safeguard Safeguard DC DC

• When the RHRSW subsystem B is inoperable to allow for repairs of of the the RHRSW B subsystem piping with Limerick Generating Station Station Unit 2 Unit 2 shutdown, reactor vessel head removed and and reactor cavity flooded, the the following equipment will be verified as available and protected as defined defined in in procedure OP-AA-108-117:

OP-AA-108-l 17:

o ESW loop B o Unit 11 LPCI subsystems Band B and D 0 o 012, D12, 014, D14, and 024 D24 4kV buses and emergency diesel generators o Unit 11 Division 2 and Division 4 Safeguard DC

• When the RHRSW subsystem B is inoperable to allow for repairs of the RHRSW B subsystem piping with Limerick Generating Station Unit 1 1 shutdown, reactor vessel head removed and reactor cavity flooded, the following equipment will be verified as available and protected as defined in OP-AA-i 08-117:

procedure OP-AA-108-117:

o ESW loop B o Unit 2 LPCI subsystems Band B and 0D o D12, 022, 012, D22, and 024 D24 4kV buses and emergency diesel generators o Unit 2 Division 2 and Division 4 Safeguard DC e.

e. Commitment Commitment #3 states that switchyard activities that "adversely exposure are adversely affect risk exposure" to be be prohibited.

prohibited. The staff does not understand the scope of activities that are intended to to be be prohibited.

prohibited.

Response

Response Compensatory measure #3 Compensatory measure #3 has been redefined as shown below.

has been

3. in the Activities in

3. Activities the switchyard switchyard that that adversely affect risk exposure are those that have the potential the potential toto cause cause aa total loss power. Therefore, the at*power loss of offsite power. at-power unit will be switchyard will switchyard protected in be protected its entirety in its equipment in entirety and equipment in the the outage unit switchyard supporting switchyard operability of supporting operability of its its offsite source will be protected during the offsite source subsystem piping RHRSW subsystem RHRSW piping repairs. equipment will be repairs. This equipment be protected as defined in in procedure OP-AA-108-117 procedure Op*AA-1 and in accordance 08-117 and in accordance with station procedure OP-LG-108-station procedure OP*LG-108-

Request for Additional Response to Request Additional Information Information Attachment 11 Attachment Nos. 50-352 Docket Nos. 50-352 andand 50-353 50-353 Page 15 Page 15 of of 21 21 1117.

17. This will bebe controlled controlled viavia the special special procedure procedure developed specifically to developed specifically to govern plant plant operation while while in in the the extended extended AOTs.

AOTs.

f. "0perational Risk Activities Commitment #4 identifies Operational Activities" are are to to be "restricted." The be restricted. The staff staff does not understand the use use ofof the term term restricted, II restricted, nor II nor does understand the does itit understand the scope scope "0perational Risk Activities.

of Operational Activities."

Response

Response Operational Risk Activities (ORAs), as defined defined in procedure WC-AA-104, involve procedure WC-AA-104, involve activities on risk significant systems that have the potential potential to derate plant, i.e.,

derate the plant, Le.,

cause a loss of planned generation. Typical ORAs involve: an activity activity that could cause cause equipment actuations that could cause loss of planned generation; instrument, instrument, fuse,fuse, or or circuit board removal/installation; an activity that will cause aa 1/2 V2 scram or V2 trip; or 1/2 trip; pressurization of common instrument sensing lines; placing of jumpers jumpers or lifting lifting energized leads; an activity that could cause vibration or impact near operational operational risk sensitive equipment, etc. Such activities will be prohibited on the online unit during the unit during the RHRSW piping repairs. Exceptions to this must be approved by the senior plant management. This will be controlled as part of the special procedure developed specifically to govern plant operation while in the extended AOTs.

g. Commitment #7 identifies shift briefs and walkdowns to reduce manage" transient "reduce and manage combustibles. The staff does not understand how the treatment of transient combustibles will be different than normal operations.

Response

Unattended transient combustibles and hot work will be prohibited in the areas listed below below during the extended AOT. This will be controlled as part of the special procedure developed specifically to govern plant operation while in the extended AOTs.

developed For an IA For AI RHRSW subsystem outage window:

• • Fire 15, Fire Area 15, Unit (D12) safeguard 4kV switchgear room Unit 11 Division 2 (012)

• • 17, Fire Area 17, Fire Unit (D22) safeguard 4kV switchgear room Unit 2 Division 2 (022)

• • Fire 24, Fire Area 24, Main Control Room (ECCS B panel 10-C601 (Bay A, B))

Main

• • Fire Area Fire 24, Area 24, Main Control Room (ECCS B panel 20-C601 (Bay A, B))

Main Control

• • Fire Fire Area 25, Auxiliary Equipment Room For an IB For an BI RHRSW subsystem outage RHRSW subsystem outage window:

• • FireFire Area 13, Unit Area 13, (Dli) safeguard 4kV switchgear room Division 11 (011)

Unit 11 Division

• • FireFire Area 19, Unit Area 19, Division 11 (021)

Unit 22 Division (D21) safeguard 4kV switchgear room

• • Fire Main Control 24, Main Area 24, Fire Area Room Control Room (ECCS panel 10-C601 (Bay C, 0, (ECCS A pane110-C601 D, E, F))

• • Fire 24, Main Area 24, Fire Area Control Room Main Control panel 20-C601 (Bay C, 0, (ECCS A panel Room (ECCS D, E, F))

• • FireFire Area 25, Auxiliary Area 25, Equipment Room Auxiliary Equipment Room

• • FireFire Area 26, Remote Area 26, Panel Shutdown Panel Remote Shutdown

Response to Request for Additional Information Attachment 11 Docket Nos. 50-352 and 50-353 Page 16 of 21 16 of 21

9. The following compensatory measures have been historically used to help ensure continued safe operation of plants during extended EDG outages outages. Please provide a discussion measures for LGS:

regarding your consideration of the following potential compensatory measures

a. Avoiding scheduling of this planned maintenance during seasons when the probability of of grid stress conditions are high or forecasted to be high.

Response

The proposed LAR is intended to support repair of one RHRSW subsystem only with one reactor unit shutdown, the reactor vessel head removed and reactor cavity flooded.

Rarely, if ever, will these conditions exist outside of the scheduled refuel outage at the end of each fuel cycle. Limerick refuel outages are purposely scheduled to occur in the later winter, early spring time frame to align with low grid stress conditions. In the unlikely event that an unplanned reactor shutdown would necessitate fuel movement, use of the extended AOT ACT would not likely be possible due to the significant amount amqunt of pre-outage planning and mobilization effort that would be required to execute an RHRSW piping work window.

b. Contacting the system load dispatcher prior to starting this maintenance to ensure no significant grid perturbations are expected during the extended ACT.AOT.

Response

Contacting the system load dispatcher prior to starting the maintenance window and during the early stages of the window allows for the forecast of grid instability to be considered in the decision to either continue into the maintenance window or to halt the Cnce the maintenance window extends beyond work prior to the start of pipe removal. Once the start of pipe removal, maintaining contact with the system load dispatcher serves to heighten the awareness of the operators to the potential for a loss of off-site power due to grid instability. This will be controlled by the special procedure.

c. Verifying that the required systems, subsystems, trains, components, and devices that depend on the remaining EDG(s) are operable and positive measures will be provided to preclude subsequent testing or maintenance activities on these systems, subsystems, trains, components, and devices.

Response

The new proposed TS LCO LCC 3.7.1.1, Actions a.3.a) and a.3.b), and the compensatory measures described in the LAR and in the responses to these RAI questions identified the equipment that is required to be protected. Therefore, no additional equipment need be maintained operable or protected.

10. The LAR, Attachment 1, states that planned RHRSW maintenance will begin with the 2012, 10.

LGS Unit 11 refueling outage. Please provide more detail regarding the planned work schedule for the currently-identified RHRSW system repairs. How will the use of the

Response to Request for Additional Information Information Attachment 11 Attachment Oocket Nos.

Docket Nos. 50-352 50-352 and and 50-353 50-353 Page 17 Page of 21 17 of 21 extended ACT AOT (including (including the EDG EOG ACT)

AOT) bebe managed managed beyond beyond the period of the period of the the currently currently contemplated repairs?

Response

Response The proposed LAR is is intended only only to support replacement of of the the non-isolable portions of non-isolable portions of the common unit RHRSW return headers. headers. Tentative Tentative station station planning funding will and funding planning and will allow allow for replacement of 100 piping that is accessible over the next 100 percent of this piping next twotwo refuel outages for each reactor unit starting after the Unit outage in refueling outage Unit 22 refueling 2011, i.e.,

in 2011, Le., A

'A' RHRSW return loop in the 2012 and 2014 Unit 11 refueling outages, outages, and IB RHRSW the B and the I RHRSW return loop in the 2013 and 2015 Unit 22 refueling outages. The maintenance maintenance window scope scope for each refuel outage has been defined based on the amount of common RHRSW amount of common RHRSW return return piping that could be replaced in approximately five days allowing the remaining two days allowing days of two days of the extended ACT AOT to be reserved for unexpected delays. The controls and and limitations limitations necessary to support the extended ACTs, AOTs, as discussed in the original LAR and in this RAI response, would be implemented for each of the targeted refueling outages in in the same manner. Any repairs conducted after these dates requiring the use of the extended ACT AOT would be managed identically to these repairs, requiring the same compensatory actions, entry conditions and use of the same special procedure to govern line-up and operations of the RHRSW and ESW systems.

11. In the LAR, Attachment 1, Section 4.2, Compensatory Measure Item 2b, the licensee states that the availability of EOG Dli, D21, and 023 EDG 011,021, D23 will be verified when RHRSW subsystem A will be unavailable. Explain the basis for not requiring verification of the availability of EDG EOG 013 D13 when RHRSW system A will be unavailable.

Response

This compensatory measure was based on providing power to all ESW and RHRSW pumps in in operable or available flow loops. From a review of UFSAR Table 8.3-3, it can be seen that ESW ESW pumps are powered by the 011, D12, 023 Dii, 012, D23 and 024 D24 diesels. RHRSW pumps are powered powered by by the Dli, 011, Dl 012,2, D2i 021 and D22 022 diesels. The Di 013 3 diesel does not power either an ESW ESW or or RHRSW RHRSW pump. pump. Therefore, during a Unit 11 outage, 013 D13 is not needed to meet TS requirements for Unit 22 or to maximize cooling system flows. Similarly, during a Unit 2 requirements outage, outage, with with the the 'B I B RHRSW RHRSW loop out D22 diesel is not needed to meet TS out of service, the 022 requirements requirements for for Unit because itit does not power an ESW pump and the RHRSW pump it Unit 11 because powers powers is in the is in BI loop, the IB loop, which would be out of service.

12.

12. Specifically regarding the Specifically regarding the EOGs, please describe how EDGs, please how defense-in-depth will be maintained.

For For example, example, are are there there any contingency backup any contingency backup provisions that can be staged for cooling the the EOGs EDGs made inoperable by made inoperable ESW alignment by the ESW alternatively, is a supplemental AC alignment or, alternatively, source, with the source, with capability of the capability of handling station blackout handling station blackout and loss-of-offsite power loads, and loss-of-offsite available available toto supplement supplement the the existing EDGs during existing EOGs the proposed extended 7-day AOT?

during the ACT?

Request for Additional Response to Request Additional Information Information Attachment 11 Attachment Docket Nos.Nos. 50-352 50-352 andand 50-353 50-353 Page 18 Page 18 of of 21 21

Response

Response With one RHRSW return header header disabled disabled for piping piping replacement, replacement, the the associated associated ESW ESW looploop will be aligned to the operable RHRSW return return header header such such that that both both ESW ESW loops and one loops and one RHRSW loop would rely on the operable RHRSW RHRSW return header header for flow path for aa flow to the path to the spray spray pond. The possibility of a single active failure rendering the pond the ESWESW System inoperable will System inoperable will be be de-energizing the ESW loop eliminated by de-energizing loop return isolation isolation motor motor operated valves in operated valves in their their safe position. Although the ESW System will meet meet single active criteria in active failure criteria in this this alternate alignment, the ESW System System no longer meets intent of meets the intent GDC 44 of GDC 44 for for suitable suitable redundancy and separation to prevent impairment of safety assuming aa passive safety function assuming passive failure. For this reason that ESW loop loop that is not aligned to its RHRSW return normal RHRSW its normal return header will be administratively declared inoperable and the TS single ESW TS action for aa single ESW loop loop inoperable would be entered. Associated components cooled by inoperable ESW by the inoperable ESW looploop would also be administratively declared inoperable.

As discussed in the LAR, Section 4.1, 4.1 , the ESW loop components cooled by loop and associated components by the ESW loop would be considered administratively inoperable but would remain aligned for automatic initiation. Flow balance testing performed prior to the first use of of the extended extended ACT for each RHRSW subsystem will demonstrate that the ESW loop not aligned to its AOT normal RHRSW return header would be capable of providing the minimum required cooling water flow rates to all components required for safe shutdown. As such, the administratively inoperable ESW loop and associated components would be considered capable of performing their intended design function, Le., i.e., they would be expected to operate on demand and provide the required cooling and power. Given this degree of redundancy that is maintained relative to the permanently installed standby AC power sources, use of supplemental AC sources, that must be considered to be less reliable than the installed installed equipment, is not warranted.

13. For the compensatory measures identified in question 1(c) that are included in the TS

13. For and/or controlled by other mechanisms, how will operations personnel confirm that the required compensatory actions are established and in effect? Will a completed, controlled checklist checklist of compensatory actions be made available in the Control Room? Will a special procedure procedure be be used?

used?

Response

Response Compensatory Compensatory measures specifically included in TS, required system alignments and measures specifically alignment verifications and other actions credited to minimize the impact to plant safety alignment verifications during the during the extended extended AOTs will be ACTs will contained in be contained in a special procedure. The special procedure will such activities control such will control as:

activities as:

- new proposed Actions a.3.a) and new proposed required by revised TS LCO 3.7.1.1, and a.3.b) required

- identifying the equipment identifying the protect per equipment to protect procedure OP-AA-1 08-117 during the work per procedure activity RHRSW piping (i.e., RHRSW activity (Le., piping repairs),

repairs),

the ESW that the verifying that

- verifying ESW flowflow balance verification testing has been performed prior to balance verification work activity, the work the activity, Contacting the Contacting load dispatcher the load dispatcher prior prior to to and during early and during early stages stages of of the work activity to determine grid determine stability, grid stability,

Response to Request for Additional Information Information Attachment 11 Attachment Docket Nos. 50-352 and 50-353 Page 19 Page of 21 19 of 21 guidance to alert operators of the need to remote manually align the sprayspray network network isolation valves from the winter bypass flow path to the spray spray networks, networks, andand revised compensatory measures described in Attachment 4 to this letter. letter.

This special procedure will be used in conjunction with existing plant procedures to provide provide control room operators with the necessary guidance to safely manage manage the units during the units during the extended ACTs.AOTs.

14. Please identify any changes to procedures or any new procedures that will be required to support the proposed LAR.

Response

As discussed above, a special procedure will be developed to implement the compensatory measures specifically included in TS, required system alignments and alignment verifications and other actions credited to minimize the impact to plant safety during the extended AOTs.ACTs. In addition, a routine test will be developed to perform the ESW flow balance verification testing that will be a pre-requisite of the special procedure (see response to RAI B.c). 8.c). Changes to ESW and RHRSW system operating procedures that interface with this special procedure are also anticipated.

15. In the LAR, Section 5.1 of Attachment 1 1 indicates that the emergency operating procedures (EOPs) will remain viable under the 7-day AOT ACT configuration. How was/will the EOP sufficiency be validated?

Response

The ESW loop not aligned to its normal RHRSW return header and the supported EDGs will remain capable of performing their design function although considered administratively inoperable per TS. Therefore, plant equipment that relies on ESW and the EDGs for either inoperable cooling and/or standby AC power to support emergency core cooling system operation will remain capable of performing their intended design function as directed by the emergency operating procedures. During repairs to the RHRSW subsystem piping, the EOPs ECPs will be impacted impacted in in that only one residual heat removal (RHR) heat exchanger will be available for decay heat removal; however, this configuration remains within the design basis of the decay heat plant.

plant. Additionally, the planned configuration for repairs ensures that both ESW loops and their associated EDGs will be available to perform their intended design function, and their therefore, therefore, successfully mitigate any accidents or transients.

In the LAR, Section 4.1 of Attachment 11 describes manual alignment of the spray pond

16. In 16.

sprays. How sprays. manual alignment of spray pond sprays be addressed? This is not a How will manual compensatory measure compensatory measure and is not included in that listing. What cue tells the operator that this action this action is required? Is there any time constraint? How will the operator know whether the is required?

realignment was realignment success? What is was aa success? is the recovery action? How long does the operator have to recover?

to recover?

Response to Request for for Additional Additional Information Information Attachment 11 Attachment Nos. 50-352 Docket Nos. 50-352 and and 50-353 50-353 Page 20 Page of 21 20 of 21

Response

Response For the ESW loop that is is not aligned to its its normal RHRSW return return header, start of header, start of an an ESW ESW pump will not result in automatic alignment of of the associated associated spray spray network isolation valves network isolation valves from the winter bypass flow path to the the spray spray networks.

networks. Operator action will Operator action will be required to be required to align these spray network network isolation isolation valves to thethe spray "spray" position position when required. Alignment when required. Alignment accomplished from hand of the spray network isolation valves is accomplished switches in hand switches the main in the main control room. Position indication for all motor motor operated operated spray network isolation spray network and winter isolation and winter bypass valves is provided in the main control room to aid operators in in verifying verifying proper proper system alignment and control. The special procedure that will govern system alignments govern system alignments and actions necessary to support use of the extended extended AOTs will include guidance to include guidance to alert alert operators of the need to remote manually align the spray network isolation valves of network isolation of the the cross connected ESW loop upon start of an associated ESW pump. pump.

The spray pond thermal performance analysis for the limiting design basis event event (dual unitunit shutdown from 1000/0100% power) demonstrates that the peak spray pond temperature does does not not occur until at least 18 hours2.083333e-4 days <br />0.005 hours <br />2.97619e-5 weeks <br />6.849e-6 months <br /> following the start of the event. Initial spray pond conditions for the analysis include an initial water temperature of 88°F. As discussed previously, the proposed LAR is intended to support repair of one RHRSW subsystem only with one reactor unit shutdown. In addition, the LGS refuel outages are purposely scheduled to occur in the late winter/early spring time frame when the spray pond is expected to be much cooler (spray pond water temperatures during this period are significantly below 88°F) and total spray pond heat load would be much lower. Thus, the period of time available to the operators to realign the spray network isolation valves of the cross connected ESW loop upon start of an associated ESW pump is several days. In the event that spray valves are not properly aligned, the ESW flow will still return to the spray pond through the winter bypass line. This will ensure that the ESW pumps do not operate in a dead headed condition and ESW cooling flows will be delivered.

17.

17. The LAR, LAR, Attachment 1, Sections 4.1 4.1,, 4.2, as well as, Attachment 3, Section 5.4, describes station station provisions provisions for "Alternate Shutdown. Are there any design-basis accidents Alternate Remote Shutdown."

that that would would make make "Alternate Shutdown impossible due to radiation or other extreme Remote Shutdown" Alternate Remote environmental environmental conditions in in the equipment areas or in the ingress or egress pathways?

Response

Response The The ESW ESW andand RHRSW Systems are designed for operation from alternate locations RHRSW Systems (remote panel and shutdown panel (remote shutdown auxiliary switchgear and auxiliary switchgear room) to support plant shutdown in the event that the event that main control the main becomes uninhabitable room becomes control room uninhabitable due to fire or toxic gas release.

Such Such plant plant events events that that necessitate necessitate control control room room evacuation are not postulated to occur evacuation the design with the coincident with coincident basis accidents design basis plant must be designed to mitigate.

accidents that the plant Therefore, the Therefore, the general areas that plant areas general plant must be that must remotely operate ESW, accessed to remotely be accessed RHRSW, RHRSW, and RHR pumps and RHR pumps and valves will be and valves be accessible.

accessible.

Information Response to Request for Additional Information Attachment 11 Attachment Docket Nos.

Docket Nos. 50-352 50-352 and 50-353 50-353 Page 21 Page of 21 21 of 21 REFERENCES REFERENCES 1.

1. Letter from Pamela B. Cowan (Exelon (Exelon Generation Company, Company, LLC) LLC) to U.S. Nuclear to U.S. Nuclear "License Amendment Request, Regulatory Commission, License Request, Proposed Changes to Proposed Changes to Technical Technical 3.5.1,3.6.2.3,3.7.1.1,3.7.1.2 Specifications Sections 3.5.1, 3.8.1.1 to and 3.8.1.1 3.6.2.3, 3.7.1.1, 3.7.1.2 and to Extend the Allowed Extend the Allowed Times," dated March 19, Outage Times, 19, 2010.

2. Letter from Peter Bamford, U.S.

U.S. Nuclear Regulatory Commission, to to Michael J. Pacilio, Michael J. Pacilio, Exelon Nuclear, Limerick Units 11 and "Limerick Generating Station, Units - Request for and 22 - Request for Additional Additional Information Regarding Proposed Technical Specification Allowed Outage Outage Time Extensions Extensions to Support Residual Heat Removal Service Water (RHRSW) Maintenance (TAC Nos.

Maintenance (TAC Nos.

ME3552), dated September 21, ME3551 And ME3552)," 21,2010.

2010.

3. ASMEIANS Addenda to RA-S-2008, Standard for Level 1/Large ASME/ANS RA-Sa-2009, "Addenda 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications, Applications,"

February 2009.

Analysis," Revision 2, May 2009 Guidance for Post Fire Safe Shutdown Circuit Analysis,

4. NEI 00-01, "Guidance

ATTACHMENT ATTACHME NT 22 License Amendment Request 1 and 22 Limerick Generating Station, Units 1 Docket Nos. 50-352 and 50-353 Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water Maintenance No. 2 Response to Request for Additional Information No.2

Response to Response to Request Request for for Additional Additional Information Information Attachment 22 Attachment Docket Nos.

Docket Nos. 50-35250-352 and and 50-353 50-353 Page 11 of Page of 44 RESPONSE TO RESPONSE TO REQUEST REQUEST FOR FOR ADDITIONA ADDITIONAL L INFORMAT INFORMATION ION NO.

NO.2 2 PROPOSED TECHNICAL PROPOSED TECHNICAL SPECIFICA SPECIFICATION TION ALLOWED ALLOWED OUTAGE OUTAGE TIME TIME EXTENSION EXTENSIONS S TO SUPPORT TO SUPPORT RESIDUALRESIDUAL HEAT HEAT REMOVAL REMOVAL SERVICE SERVICE WATER WATER MAINTENA MAINTENANCE NCE In Reference 1, In 1, Exelon Exelon Generation Generation Company, Company, LLC LLC (Exelon)

(Exelon) requested changes to requested changes the Technical to the Technical Specificationss (TS), Appendix A of Specification of Operating License License Nos.

Nos. NPF-39 NPF-85 for and NPF-85 NPF-39 and Limerick for Limerick Generating Station (LGS), Units Units 11 and and 2,2, respectively. The The proposed changes would proposed changes extend the would extend the TS allowed outage time (ACT) (AOT) for the Unit Unit 11 and and Unit Suppression Pool Unit 22 Suppression Pool Cooling (SPC) mode Cooling (SPC) mode of the Residual Heat Removal (RHR) system, Residual Heat system, the Residual Service Water Heat Removal Service Water (RHRSW) system, the Emergency Service Water (ESW) (ESW) system, the A.C.

and the system, and Sources A.C. Sources - -

Operating (Emergency Diesel Generators) from 72 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> seven (7) hours to seven (7) days order to in order days in allow for to allow for repairs of the RHRSW system piping.

The NRC reviewed the license amendment request and identified the need need for additional additional information in order to complete its evaluation of the amendment request. On September 28, 28, 2010, draft questions were sent to Exelon to ensure that the questions were understandab understandable, le, the the regulatory basis for the questions was clear, and to determine if the information was previously previously docketed. In Reference 2, the NRC formally issued the request for additional information information (RAI).

The questions are restated below along with Exelon's Exelons responses.

1. The LAR, Attachment 1, compensatory compensatory measure 4.2.2.b provides a listing of the various equipment whose availability is to be verified during the extended ACT. AOT.

Please Please define availability in the above context and state whether this equipment will be define "availability" immediately immediately available for use if called upon.

Response

Response Compensatory Compensatory Measure 4.2.2.b in Measure 4.2.2.b in Attachment 11 of the original submittal (Reference 1) identifies identifies the the subsystems subsystems and components that would be considered to be available to perform perform their their design design function although considered function although administratively inoperable. In the considered administratively context context of of the the statement statement in in question question the term "available" the term available implies that the subsystem or component component would would remain for automatic aligned for remain aligned automatic initiation considered to be initiation and would be considered capable of performing capable of performing their their design design function.

function. Flow Flow balance balance testing would be performed prior to to the the first first use use ofof the extended AOT the extended ACT forfor each subsystem RHRSW subsystem each RHRSW to demonstrate that the ESW ESW looploop notnot aligned aligned to its normal to its RHRSW return normal RHRSW would be header would return header capable of be capable providing of providing the the minimum minimum required required cooling flow rates water flow cooling water rates toto all components required for safe all components shutdown.

shutdown.

2.

2. In In the LAR, Attachment the LAR, Attachment 1, 1, Section Section 4.3.2, Defense in 4.3.2, "Defense in Depth Depth Philosophy,"

Philosophy, under the subtopic under the subtopic for for 'system redundancy the system redundancy' describes the submittal describes the submittal the capability of the capability of operable train the operable and the train and the compensatory measures compensatory measures to to assure the availability of the operable train. But the assure the availability of the operable train. But the section section does does notnot discuss discuss the of the matter of subject matter the subject subtopic, Le.

the subtopic, i.e. system system redundancy, independence redundancy, independence and and diversity.

diversity.

Response to Request for Additional Information Information Attachment 22 Attachment Docket Nos. 50-352 and 50-353 Page 22 of Page of 44 Discuss the available systems that may not be operable but do some measure of do provide some of redundancy, independence and diversity and discuss their capability capability during an extended extended AOT. Discuss any other systems, safety related or non safety related, which ACT. also can which also can provide some measure of redundancy, independence and diversity diversity for an extended ACT.

an extended AOT.

Response

Resoonse With the exception of the non-outage RHR heat exchanger and the two RHRSW pumps associated with the RHRSW subsystem that is disabled for pipe replacement, equipment and subsystems required to comply with plant TS for the expected plant conditions (one unit unit defined in the in refuel) will either be operable as defined by TS or will be available as defined response to RAI Question #1 above to perform its design function as described in in the the UFSAR. As discussed in the license amendment request (LAR), the heat heat removal capability of one operable RHRSW subsystem with two RHRSW pumps and one RHR heat exchanger is sufficient to mitigate all design basis events.

3. The LAR, Attachment 1, Section 3.0, states that the ESW system is designed to supply cooling water to the following safety related equipment:

a. RHR motor oil coolers

b. RHR pump compartment unit coolers

c. Core spray pump compartment unit coolers

d. Control room chillers

e. Standby diesel generator heat exchangers

f. Reactor Core Isolation Cooling (RCIC) pump compartment unit coolers

g. High-Pressure Coolant Injection (HPCI) pump compartment unit coolers

h. Spent fuel pools (makeup water)

The LAR also states that when the 'A' A RHRSW loop is inoperable, the 'A' A ESW loop will be declared inoperable and associated components cooled by the 'A' A ESW loop will be declared inoperable, as required by LGS TS 3/4.7.1.2, Action a.3. A similar statement can be be made for the '8' B ESW loop and associated components cooled by the B RHRSW loop, '8' B ESW loop. Therefore, the above listed components that are cooled by their respective

'8' ESW inoperable when the associated ESW loop is inoperable.

ESW loop are inoperable The LAR accounts The LAR accounts for the inoperability of the RHR motor oil coolers and pump compartment unit core spray pump compartment unit coolers and diesel generator heat unit coolers, core exchangers. However, the LAR does not discuss the effect of inoperability of the ESW loops exchangers.

upon control room chillers, RCIC and HPCI pump compartment unit coolers and spent fuel upon makeup water. Discuss the effect of inoperability of each ESW loop upon the above pool makeup pool listed components and whether the associated TSs are, or are not, affected.

listed components

Response

Inoperabilityof ESW does lnoperability of ESW does not affect operability of either the HPCI or RCIC systems. While ESW supplies ESW cooling water to the room coolers in the HPCI and RCIC pump rooms, the supplies cooling

Response to Request for Additional Information Attachment 22 Attachment Docket Nos. 50-352 and 50-353 Page 33 of Page of 44 room coolers are not required for either HPCI or RCIC to perform its its design design basis function.

Equipment required for functioning of the HPCI and RCIC systems have have been been qualified qualified to to temperatures exceeding the maximum temperatures expected for operation operation of of the the HPCI HPCI and RCIC systems without cooling provided by the room coolers coolers. Even Even though though the the room coolers are not required for HPCI/RCIC operability operability determination, determination, since since either either loop loop being being declared inoperable will be available and protected, the affected affected loop loop would be be expected expected toto supply cooling water to its associated room coolers as required.

Inoperability of an ESW loop does not affect operability of the Main Control Room Room Chillers.

Chillers.

While Limerick has two Main Control Room Chillers (one supplied from each ESW loop), loop),

the chillers are not governed by any TS TS. Therefore, a chiller would not be declared declared inoperable as a result of the associated ESW loop being administratively declared declared inoperable. Since either loop being declared inoperable will be available and protected, the affected loop would be expected to supply cooling water to its associated chiller as required.

Similarly, the operability of the spent fuel makeup function of ESW will not be affected by administratively declaring a loop of ESW inoperable, since spent fuel pool makeup is not governed by any TS. As described above, the loop of ESW being administratively declared declared inoperable will be available and will be a protected system during the extended LCO.

Therefore, the affected loop of ESW will still be capable of providing make-up water as required.

4. With IAAI RHRSW subsystem inoperable and drained for maintenance (Unit 2 operating and Unit 11 shutdown), the LAR states in Attachment 1, paragraph 4.1 .b, Even 4.1.b, "Even though the ESW system meets single active failure criteria in this alignment, it will not be single passive failure proof. As a result, the ESW system will not meet the requirements of [General Design Criteria] GDC 44..." 44. .

Discuss the single passive failures under consideration that cause the failure to meet GDC 44 requirements.

Response

The only passive failures that would result in failure to meet GDC 44 criteria are described below.

With the "A" A loop of RHRSW out of service and drained, a disc separation in the 012-01208 01 2-01 20B valve that blocked flow would result in a failure to meet GDC 44 criteria. Likewise, a failure B loop RHRSW return piping that resulted in flow blockage (Le..

of the "8" (i.e..,, crimping of the line) would result in line) in a failure to meet GDC 44 criteria.

the "B" With the B loop of RHRSW out of service and drained, a disc separation in the 012-0120A 01 2-01 20A valve that valve that blocked blocked flow would result in a failure to meet GDC 44 criteria. Likewise, a failure of the of the "A" A loop RHRSW RHRSW return piping that resulted in flow blockage (Le., (i.e., crimping of the line) would result in a failure to meet GDC 44 criteria.

result in

Response to Request for Additional Information Information Attachment 22 Attachment Docket Nos. 50-352 50*352 and 50-353 50*353 Page 44 of Page of 44 Both disc separation of the 01 012*120A(B) 2-1 20A(B) valve and failure of the RHRSW RHRSW return loop piping return loop piping are considered extremely unlikely events. The 012-0120A(B) 012*0120A(B) valves are stainless steel steel butterfly valves. The most likely cause of disc separation in raw water systems is valve stem is valve stem or stem nut corrosion, which is mitigated by the stainless steel material. Likewise, failure of of the RHRSW return piping is considered an extremely unlikely event. This piping is either is either contained in a missile proof, seismic II structure, or is buried. Therefore, tornado missiles or tornado missiles or seismic events would not result in failure. Since the line is carbon steel, steel, itit is is subject subject toto leakage due to corrosion. However, leakage will not result in complete flow blockage.

Additionally, since this is the return loop, system leakage would not not impair flows to components cooled by ESW or RHRSW, or the ability to transfer heat from those components Leakage from the return piping could affect long term spray pond inventory components. inventory.

However, there are multiple systems and flow paths available to provide make-up make*up to the the Spray Pond, not dependant on the RHRSW system return piping.

REFERENCES

1. Letter from Pamela B. Cowan (Exelon Generation Company, LLC) to U.S. Nuclear Nuclear License Amendment Request, Proposed Changes to Technical Regulatory Commission, "License 3.5.1, 3.6.2.3, 3.7.1.1, 3.7.1.2 and 3.8.1.1 to Extend the Allowed Specifications Sections 3.5.1,3.6.2.3,3.7.1.1,3.7.1.2 Outage Times," 19, 2010.

Times, dated March 19,2010.

2. Letter from Peter Bamford, U.S. Nuclear Regulatory Commission, to Michael J. Pacilio, Exelon Nuclear, "Limerick Limerick Generating Station, Units 1 1 and 2

• Request for Additional Information Regarding Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water (RHRSW) Maintenance (TAG (TAC Nos.

ME3552),

ME3551 And ME3552)," dated 30, 2010 September 30,2010.

ATTACHMENT 3 License Amendment Request Limerick Generating Station, Units 11 and 22 Docket Nos. 50-352 and 50-353 Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water Maintenance Revised Proposed Technical Specifications Pages 1 TS Pages Unit 1 3/4 6-16 3/46-16 3/47-1 3/4 7-1 3/4 7-3 3/48-1 3/4 8-2 Unit 2 TS Pages 3/4 6-16 3/46-16 3/47-1 3/4 7-1 3/4 7-3 3/4 8-1 3/4 8-2

CQNfAINMENf CIIftIMNMENI SYSrEMS SYSIEMS SUPPRESSION 5UPPRESSION POOLPOOL COOLING COOLING 3.6.2.3 3.6.2.3 rhe uppression pool fhe suppression pool cool Inq mode cooling mode of of the the residual residual heat heat removal removal (RHR)

(RHR) system y tern shall hall be be OPERABLE OPERABLE withwith two two independent independent loops,loops, eacheach loop loop consisting consisting of: of:

a.a. One One OPERABLE OPERABLE RHR RHR pump, pump, and and b.b. An An OPERABLE OPERABLE flow flow path path capable capable of of recirculating recirculating water water from from the the suppression suppression chamber through chamber through an an RHR RHR heat heat exchanger.

exchanger.

APPLICABILITY APPLICABILITY: OPERATIONAL OPERATIONAL CONDITIONS CONDITIONS 1, 1, 2, 2, and and 3.

3.

ACIION:

a.

a. With one With one suppression suppression poolpool cooling cooling loop inoperable, restore restore the the inoperable inoperable loop to loop to OPERABLE OPERABLE status status within 72 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> hour or be in at at least least HOT HOT SHUTDOWN SHUTDOWN within the within the next next 12 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> andand in COLD SHUTDOWN within the the following following 24 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

hours.

b. With both suppression pool cooling loops inoperable, be be in in at at least least HOT HOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN* SHUTDOWN* within within the next 24 the next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

hours.

iLLANCLREQUiJEMENIS 4.6.2.3 4.6.2.3 The suppression The suppression pool cooling mode of the RHR system shall be be demonstrated demonstrated OPERABLE OPERABLE::

a. In accordance with the Surveillance Frequency Control Program Program by by verifying verifying that each valve (manual, power-opera power-operated,ted, oror automatic) automatic) in in the the flow path that is not locked, sealed, or otherwise otherwise secured secured in in positio position, n, is is inin its correct position.

b.

b. By By verifying verifying that each each of of the required required RHR RHR pumps pumps develops develops aa flowflow ofof atat least least 10,000 10,000 gpm gpm onon recircu recirculation through the lation flow through the flow flow path path including including the RHR the RHR heat exchanger exchanger and and itsits associated associated closed closed bypass bypass valve, valve, the the suppression suppression pooipool andand the the full full flow flow test test line line when when tested tested pursuant pursuant to to Specification Specification 4.0.5.4.0.5.

kWhenever both RHR subsystems k Whenever both RHR subsystems are are inoperable, inoperable, if if unable unable to to attain attain COLD SHUTDOWN SHUTDOWN COLD as as required required by by this this ACTION, ACTION, maintain maintain reactor reactor coolant coolant temperature temperature as low as low as as practic al by practical by use use ofof alterna alternatete heat heat removal removal methods.

methods.

4rA LIMERICK LIMERICK - UNIT UNIT 11 3/4 3/4 6-16 6-16 Amendment No.

Amendment No. 9+, ,~, , 186

+J+, 186 g&, 4-4,

INSERT [Al INSERT fA] (SPC (SPC 3.62.3.a) 3.6.2.3.a)

• • During the extended 7-day 7-day Allowed Allowed Outage Outage Time Time (ACT)

(AOT) specified specified by by TS TS LCO LeO 3.7.1.1, 3.7.1.1, a.3.a) or Action a.3.a) or a.3.b) a.3.b) to to allow allow for for RHRSW RHRSW subsystem SUbsystem piping piping repairs, repairs, the the 72-hour 72-hour ACT AOT for for inoperable suppression pool one inoperable pool cooling loop loop may may also also be be extended extended toto 77 days days for for the the same same 7-day period.

LGS LGS Unit Unit 11

3/4.7 3/4.7 PLANTPlANT SYSTEMS SYSTEMS 3/4.7.1 3/4 7 1 SERVICE SERVICE WATER WATER SYSTEMS SYSTEMS

) RESIDUAL RESIDUAL HEATHEAT REMOVAL REMOVAL SERVICE SERVICE WATER WATER SYSTEM SYSTEM - COMMON

- COMMON SYSTEM SYSTEM

~lN§ CONDITION FOB LIMITING CON~LlLoN FOR Oe~~

OPERATION 3.7.1.1 3.7.1.1 At At least least the the following following independent independent residual residual heat removal service service water water (RHRSW)

(RHRSW) system system subsystems, subsystems, withwith each each subsystem subsystem comprised comprised of:

a.

a. Two Two OPERABLE OPERABLE RHRSW RHRSW pu.ps, pumps, and and b.

b. An An OPERABLE OPERA8LE flow flow path capable of taking suction fro. from the the RHR RHR service service water pumps water pumps wet pits which which areare supplied fra. from the spray spray pond pond or or the the cooling cooling tower basin and transferring the water through one one Unit Unit 1I RHR RHR heat heat exchanger, exchanger, shall shall be be OPERABLE:

OPERABLE:

a. In OPERABLE CONDITIONS CONDITIONS I, 1, 2, and 3. 3, two subsyst..s.

subsystems.

b. In OPERABLE CONDITIONS CONDITIONS 4 4 and 5.5, the subsystem(s) associated with with systems and components required OPERABLE by Specification 3.4.9.2, 3 4 9 2, 3.9.11.1, and 3.9.11.2.

APPLICABILITY:

APPLICABILITY OPERATIONAL OPERATIONAL CONDITIONS CONDITIONS I, 1, 2, 3, 4, and S. 5.

ACTION; ACTION:

a. In OPERATIONAL OPERATIONAL CONDITION I, 1, 2, or 3:

1. With WIth one RHRSW pump inoperable. inoperable pump inoperable, restore the inoperable pump to to OPERABLE status within 30 days, or be in at least HOT HOT SHUTDOWN SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in 1n COLD SHUTDOWN within within the the following following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

2. With one RHRSW pump in each subsystem subsyst.. inoperable, restorerestore at at 1least east one of the inoperable RHRSW pumps pumps to OPERABLE OPERABLE status status within 77 days or be in at least HOT SHUTDOWN SHUTDOWN within the the nextnext 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

hours.

3. subsystem otherwise With one RHRSW subsystem otherwise inoperable, inoperable, restore restore the the inoperable subsystem subsyst.. to OPERABLE status status with with at at least least oneone OPERABLE RHRSW pump within 72 72 hourjVor hour or be be in in at at least least HOTHOT SHUTDOWN within the next SHUTDOWN next 12 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />sjnd hou nd in in COLD COLD SHUTDOWN S WN within within

~t---_...,<

-:= B the following following 24 24 *hours. )ul?le.s.$ eNq,.ses~ i,.. 4:\.">.'-

. . . ,v~ ) bc..lt>w)

• 4. With both WIth both RHRSW RHRSW subsystems subsystems otne0 noperable, restore noperable, restore at at least one least one subsystem subsyst.. toto OPERABLE OPERABLE status status within within 88 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br /> hours or or bebe inin at at least least HOT HOT SHUTDOWN SHUTDOWN within within thethe next next 12 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> hours and and in in COLD COLD SHUTDOWN SHUTDOWN** within within the the following following 24 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

hours.

• Whenever both RHRSW

• Whenever both RHRSW subsystems subsystems areare inoperable, inoperable, if if unable unable to to attain attain COLD COLD SHUTDOWN as required SHUTDOWN as required by the ACTION, maintain reactor coolant by the ACTION, maintain reactor coolant temperature temperature as as low as practical low as practical by by use use ofof alternate alternate heat heat removal removal methods.

methods.

LIMERICK - UNIT LIMERICK -

UNIT 11 3/4 7-1 3/4 7-1 Amendment Amendment No. 58, es, No. 58, 86, 131 131 NOV 11 56 18 NOV lQQ8

raj (RHRSW INSERT [Bi (AHASW 3.7.1.1 3.7.1.1.a.3)

.a.3 a) When the A a> 'A' RHRSW AHRSW subsystem is inoperable to allow allow for repairs repairs of of the the A

'A' RHRSW AHASW subsystem piping, with Limerick Generating Station Station Unit Unit 22 shutdown, shutdown, reactor reactor vessel vessel head head removed and reactor cavity flooded, the 72 72-hour Allowed Outage hour Allowed Outage Time Time maymay be extended to be extended to 77 days once every other calendar year with the following compensatory measures measures established:

established:

1)

1) The following systems and subsystems will be protected protected in accordance with in accordance with applicable applicable station procedures:

I

• B RHRSW subsystem

'B RHASW I

• 'B B ESW loop I 1

• B 'B and D '0 RHR AHA subsystems

• 012, D14, D22, 022, and D24 4kV buses and emergency diesel diesel generators generators

• Division 2 and Division 4 Safeguard DC, and

2) The IA AI and 'BI B loop of ESW return flow shall be aligned to the operable B 'BI RHRSW AHASW return header only. The ESW return valves to the B 'BI RHRSW AHASW return headerheader (i.e.,

(Le., HVHV-11-015A 11-01 5A and HV-11-015B)

HV-1 1-01 5B) will be administratively controlled in the open position and de-energized prior to entering the extended AOT. The ESW return valves to the A 'A' AHASW RHRSW return header (Le., HV-1 1-011 A and HV-i (i.e., HV-11-011 1-011 B) will be administratively HV-11-011 controlled in the closed position and de-energized as part of the work boundary.

b) When the 'B' RHRSW subsystem is inoperable to allow for repairs of the B B AHRSW 'BI RHRSW AHASW subsystem piping, with Limerick Generating Station Unit 2 shutdown, reactor vessel head removed and reactor cavity flooded, the 72-hour Allowed Outage Time may be extended to 7 days once every other calendar year with the following compensatory measures established:

1) The following systems and subsystems will be protected in accordance with applicable station procedures:

• 'AI A RHASW RHRSW subsystem I

A ESW loop

• IA

• 'AI A and 'CI RHR subsystems C AHA

• • D11,Dli, D13,Dl 3, 021, and 023 D23 4kV buses and emergency diesel generators

• • Division 11 and Division 3 Safeguard DC, and

2) The IAI A and 'B BI loop of ESW return flow shall be aligned to the operable 'A' A RHRSW AHASW return header only. The ESW return valves to the 'AI A AHASW RHRSW return header (Le., (i.e., HV-HV 11-01 1A 11-011 HV-1 1-011 B) will be administratively controlled in the open position and A and HV-11-011 de-energized prior de-energized prior to entering the extended AOT. The ESW return valves to the 'B BI RHRSW return RHASW return header (Le.,(i.e., HV-11-015A HV-1 1-01 5B) will be administratively HV-i 1-01 5A and HV-11-015B) controlled in controlled in the closed position and de-energized as part of the work boundary.

Unit 11 LGS Unit LGS

PLANT SYSTEMS EMERGENCY SERVICE KATER WATER SYSTEM - COMMON SYSTEM JJ.!1WN§ CQ~.:a9lf _

LIMITING CONDITION FOR OPERATION 3.7.1.2 At least least the following foflowing independent Independent emergency service water systemsyst.. loops, with lach each loop comprised of:

a. Two OPERABLE emergency service water pumps, and

b. An OPERABLE flow path capable capabl. of taking suction fromfro. the emergency service water pumps wet pits which are supplied from fro. the spray pond or the cooling tower basin and transferring the water to the associated Unit 11 and common comeon safety-related equipment, shall be OPERABLE:

a. In OPERATIONAL CONDITIONS 1, I, 2, and 3, two loops.

b. In OPERATIONAL CONDITIONS 4, 5, and *, ,

on. loop.

one APPLICABILIUj APPLICABILITY OPERATIONAL CONDITIONS I, 1, 2, 3, 4, 5, and *. *.

ACTION; ACTION

a. In OPERATION CONDITION I, 1, 2, or 3:

1. With WIth one emergency service water pump Inoperabi inoperable,e, restore the inoperable pump to OPERABLE status within 45 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

2. With one emergency service water pump in each loop inoperable,inoperab1 **

restore at least one inoperable pump to OPERABLE status within 30 days or be in In at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and 1nin COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3. With one emergency service water syste. system loop otherwise inoperable, declare all equipment aligned to the inoperable inoperable.

inoperable**, restore the inoperable loop to OPERABLE loop inoperable",

status with at status with at least one OPERABLE least one OPERABLE pump within 72 pump within hour~.

72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> ~e or in be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. ~

• When handling irradiated fuel in the secondary containment.

• When "The The diesel generators **y be aligned to the OPERABLE emergency service water may b.

syst..

system loop prOVided confinaltory flow testing hiS provided confirmatory has been performed.

perforMd. Those diesel generators no aligned to the OPERABLE emergency service s1st..

water system loop shall bt be declared inoperable and the actions of 3.8.1.1 taken.

@~i:) I LIMERICK - UNIT 11 3/4 7-3 73 Amendment No.

Amendment a, *,

No. 2, 4, Be, 88, 131 NOVI1 61998 NOV 6 1998

eel INSERT [Cl (ESW 3.7.1.2.a.3)

During the extended 7-day Allowed Outage Time (ACT)

(AOT) specified LeO 3.7.1.1, specified by TS LCO 3.7.1.1, Action a.3.a) or a.3.b) to allow for RHASW the 72-hour RHRSW subsystem piping repairs, the 72-hour ACT AOT for for one inoperable emergency service water system loop loop may also be be extended extended to to 77 days days for the same 7-day period.

Unit 11 LGS Unit LGS

3/4.8 314.8 ELECTRICAL POWER SYSTEMS 3/4.8.1 314.8.1 A.C. SOURCES

) A.C.

A.C. SOURCES*

SOURCES OPERATING lIMITING LIMITING CONDITION CONDIT1ONF0R FOR OPERATION 3.8.1.1 3.8.1.1 As a a minimum, the following A.C. electrical power sources shall be OPERABLE:

OPERA8LE:

a. Two physically independent circuits between the offsite transmission network and the onsite Class 1E distribution system, and

b. Four separate and independent diesel generators, each with:

1.

1. A A separate day tank containing aa minimum of 250 gallons of fuel,

2. A 33,500 A separate fuel storage system containing aa minimum of 33,500 gallons of fuel, and

3. A A separate fuel transfer pump.

APPLICABILITY: OPERATIONAL CONDITIONS 1, 2, and 3.

ACTION:

a. With one diesel generator of the above required A.C. electrical power sources inoperable, demonstrate the OPERABILITY of the remaining A.C.

sources by performing Surveillance Requirement 4.8.1.1.1.a 4.8.1.1.I.a within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and at least once per 77 days thereafter. If the diesel generator became inoperable due to any cause other than an inoperable support system, an independently testable component,'

component, or preplanned preventive maintenance or testing, demonstrate the OPERABILITY of the remaining operable diesel generators by performing Surveillance Requirement 4.8.1.1.2.a.4 4.8.1.1,2.a.4 for one diesel generator at aa time, within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, unless the absence of any potential common-mode failure for the remaining diesel generators is determined. Restore the inoperable diesel generator to OPERABLE status within 30 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLDCOLO SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. See also ACTION e.

b. With two diesel generators of the above required A.C. electrical power sources inoperable, demonstrate the OPERABILITY of the remaining A.C.

sources by performing Surveillance Requirement 4.8.1.1.1.a 4.8.1.1.I.a within 11 hour1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter. If either of the diesel generators became inoperable due to any cause other than an inoperable support system, an independently testable component, or preplanned preventive maintenance or testing, demonstrate the OPERABILITY of the remaining diesel generators by performing Surveillance Requirement 4.8.1.1.2.a.4 4.8.1.1.2.a..4 for one diesel generator at aa time, within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, unless the absence of any potential common-mode failure for the remaining diesel generators is determined. Restore at least lea~st one of the inoperable diesel generators to OPERABLE status within 72 hou or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COL SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. See also ACTION e.

o CiL~ 4, 4,193 LIMERICK - UNIT 11

- 3/4 8-1 Amendment No. ~,

, 40, ~,193

[OJ (EDGs INSERT [Dl (EDGs 3.8.1.1.b) 3.8.1.1.b) extended 7-day During the extended 7-day Allowed Allowed Outage Outage Time Time (ACT)

(AOT) specified specified byby TS TS LCO LeO 3.7.1 3.7.1.1,

.1, Action aa.3.a) 3 a) or aa.3.b) to allow 3 b) to allow for RHRSW subsystem subsystem piping piping repairs, repairs, the the 72 72-hour AOT for hour ACT for two inoperable diesel generators may may also also be be extended extended to days for to 77 days for the the same same 7-day 7-day period.

Unit 11 LGS Unit LGS

WC(T!J;&.PObER fLEC7UCAL eM! SYST $VS r1M

) LIMiTING CONDmOfl FOR LIMtTtN!i CONDITION O'PATJOI1 (Continued)

FOI OPERATION (Contin....)

ACTtON:

ACTION: (Conti......)

(Continued)

• . In additio in aMI t10n n tO ACTIONS above:

tftlI ACTIONS to the above:

1.

1. 'Of' For o tile the tMt train above

~ . with t...1. systs, required A.

A.C. C.

one or wita one eledr1a1 electric al pr d1_1 generators tIP more diesel ourcu sources 1 u .. of inoperable, af 1**

vertty within verify wlta1. I2 hours and at least and at 1H1t onci per 32 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereaf Vlerutte. ter tbat at that It least

, .......

• t the one of PICIUi.... WI train tile required tra1** ys,- saystam syst qsu..,

trat.. cuppenents, train, ~ . and dwtCIII is and devices t. OPUAIII DPlUlLi and Its uHC1.tacI 1t1 associated dte..'

diesel generator ur 11 is GPDAlLE.

OPERASLI. Otherwise, OtIIIrwf restore

'18.. either 11tMr the VIe 1

inoperable ,. diesel

<<11_1 generator

........... tIII~1 or the I .,sa. sabsystes

. ,* syst able luIaIyIU.

tAt * *flAlLl toanOP ItatuI wtta1.

IUILI statu.w 2 itJsin77J ." orbeln at, , . .NOT lie 1natleast . lIlT SIII'IDCMI within "" nat vitftf. the nut. 12 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />

..... In SIII'rDCMt within COLI S1#JTDO

f. COLD wttl'd.

SI*JTD t." ....... 24 tile following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

the ~. -Jt-

2. , ** the For above witllf. I within LPCJ-,

tile LPCI systaes, with required A.C.

2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> and at

.1edr1ca1 d 1.an WI or wita tve Ate. electric al pr sources least once per ,.. 12 1..,..,*.

......un of d1...1 generators tIP more diesel

...-eM inoperable, verify u.nafter 11 hears thereaf 01 the the vrtfy ter that tad at at, 1

least tw of the tile ...... 1... LPCI required LPCJ .,....

syst sabsystamo, u.. trains, t.rat...

cconent ....u....

a, and dlriCli devices are GPIUIU and Iti IN OPERABLE 1t1 associatad ulOC1l'&1M1 dieseldi...,

.._rater genera tor is fl GPIIMLL OPERABLE . OUIIrwt M. be Otherwise, lie 1.

in at leat. HOT d least SIIII1'DIMIl lIlT SIIJTX within tile witllf. next 12 ..........

the ned hours and 1. COLI SI*flDOdI In COLD SIIITDCIII within wttftf. U. the

'.".-1.24.........

followIng 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. .

This AC11DN 11111 ACTION . . . .-t does not . " fop apply ~ covered those. .syst for tho. CO".... In t. Specif ications Spec1f1cat1OD1 3.7.1.1.

3.7.1.1. and 3.7.1.2.

3.7.1.2.

LIMERICE *- LCT UJlDlCI EMIT 11 3/4 3/4 ..2 12 Amennt No. II.4G

.......... U. 40 I$

.a **

MAT 3 0 190

INSERT [El (EDGs 3.8.1.1.e.1)

• • During the extended 7-day Allowed Outage Time (ACT)

(AOT) specified by by TS TS LCO LeO 3.7.1 .1, 3.7.1.1, Action a.3.a) or a.3.b) to allow for RHRSW subsystem piping piping repairs, the 72-hour 72-hour ACT AOT may may also be extended to 7 days for the same 7-day period.

Unit 11 LGS Unit LGS

(:QNrAINMENI ST EMS SijffjS5jj)N_POOLQ)jJjL I.

3.6.2.3 rhe 3.6.2.3 Fhe suppression suppression pool poe1 cooling cooling mode mode of of the the residual residual heatheat removal removal CRHR)

(RHR) system shall be OPERABLE system shal I be OPERABLE with two with two independent independent loops, loops, each each loop loop consisting consisting of: of:

a,

d. One OPERABLE One OPERABLE RHR RHR pump, pump, andand b.b. An OPERABLE An OPERABLE flowflow path path capable capable of of recirculating recirculating water water from from thethe suppression suppression chamber through chamber through an an RHR RHR heat heat exchanger.

exchanger.

APPLICABILITY:

APPLICABILITY: OPERATIONAL CONDITIONS OPERATIONAL CONDITIONS 1, 1, 2, 2, andand 3.

3.

ACTION:

ACTION:

a.

a. With one With one suppression suppression pool pool cooling cooling loop loop inoperable, restore restore the the inoperable inoperable loop to OPERABLE loop to OPERABLE status status within within 72 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> hour or or be inin at at least least HOTHOT SHUTDOWN SHUTDOWN within the within the next next 1212 hours0.014 days <br />0.337 hours <br />0.002 weeks <br />4.61166e-4 months <br /> hours and and in in COLD COLD SHUTDOWN SHUTDOWN within within thethe following following 24 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

hours.

b. With both With both suppression suppression pool coolingcooling loops inoperable, inoperable, be be inin at

b. at least least HOTHOT SHUTDOWN within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN*

SHUTDOWN SHUTDOWN* within within the the next 24 next 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

hours.

4.6.2.3 The 4.6.2.3 The suppression suppression pool cooling cooling mode of the RHR system shall be be demon demonstrated OPERABLE: strated OPERABLE:

a.

a. In In accord ance with the Survei accordance Surveillance Frequency llance Freque Controll Progra ncy Contro Programm by by verifyi verifying ng that each valve valve (manu (manual, power-operated, al, power- operated, or or autom automatic) in the the atic) in flow path flow path that is is not locked locked,, sealed, sealed, or or otherw otherwise secured ise secure d inin positio position,n, is in is in its its correct correct positio position. n.

b.

b. By verifyi By verifyingng that that each each ofof the the require required RHR pumps d RHR pumps develo develops ps aa flow flow of of at at least least 10,000 10,000 gpm gpm onon recircu recirculation lation flow flow throug through the flow h the flow path path includ includinging the the RHR RHR heat heat exchan ger and exchanger and its its associa associated closed bypass ted closed bypass valve, valve, the the suppre ssion pool suppression pool and and the the full full flowflow test test line line when when tested tested pursua pursuant to nt to Specif ication 4.0.5.

Specification 4.0.5.

• Whenever both RHR subsystems are inoperable, if

• Whenever both RHR subsystems are inoperable, if unable unable toto attain attain COLD COLD SHUTDOWN SHUTDOWN as as require d by required by this this ACTION, ACTION, mainta maintainin reactor reactor coolan coolant temperature t temper ature as as low low asas practic practicalal byby use use ofof alterna alternatete heat heat remov al method removal methods. s.

LIMERICK LIMERICK - UNIT UNIT 2 2 3/4 3/4 6-16 6-16 Amendment Amend ment No. No. 3.0, JG, Z.0, ~,147

+Q, p.2,147

INSERT FA1 INSERT rAJ (SPC 3.6.2.3.aI 3.6.2.3.a)

• • During the extended 7-day 7-day Allowed Allowed Outage Outage Time Time (ACT)

(AOT) specified by TS specified by LCO 3.7.1.1, TS LCO 3.7.1.1, Action aa.3.a) 3 a) or aa.3.b) allow for RHRSW 3 b) to allow RHRSW subsystem subsystem piping piping repairs, repairs, the the 72 72-hour AOT for hour AOT for one inoperable suppression suppression pool pool cooling cooling loop loop may may also also be extended to be extended to 77 days the same for the days for same 7-day period.

LGSUnit2 LGS Unit 2

PLANT SYSTEMS 3/4.1 PlANT 3/4.7 It!i6ulc ij~i,VAlBQ~~lE!Ei~j~~HiATER 3/4 7 1 SERVICE WATER SYSTEMS RESIDUAL HEAT REMOVAL SERVICE WATER SSTEM SYSTEM - COMMON

- COMMON SYSTEM SYSTEM

~~J!NG CONDITION LIMITING fOR OPERATION CONDIJIQ! FOR QPERATIOH 3.7.1.1 3.7.1.1 At least least the following independent residual heat heat removal removal service service water water (RHRSW) system (RHRSW) system subsystems, subsystems, with each subsystem comprised of: of:

a.

a. Two OPERABLE RHRSW pumps, and b.

b. capable of taking An OPERABLE flow path capable taking suction suction from thethe RHR RHR service service water pumps wet pits which are supplied from the spray spray pond pond oror the the cooling tower basin and transferring the water throughthrough oneone Unit Unit 22 RHR heat exchanger, shall be OPERABLE:

a. In OPERATIONAL CONDITIONS 1, 1, 2, 3, two subsystems.

2. and 3,

b. In OPERATIONAL CONDITIONS 44 and 5, the subsystem(s) associated with with systems and components required OPERABLE by SpecIfication Specification 33.4.9.2, 4 9.2, 3.9.11.1, and 3.9.11.2.

ApPLICABILITy; APPLICABILITY OPERATIONAL CONDITIONS 1, 2, 3, 4, and 5. s.

ACTION:

a. In OPERATIONAL CONDITION 1, 2, or 3:

1. With one RHRSW pump inoperable, restore the inoperable pump to OPERABLE status within 30 days, or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the follOWing following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

2. With one RHRSW pump in each subsystem inoperable, restore at least 1 east one of the inoperable RHRSW pumps to OPERABLE status within 77 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the follOWing following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3. With one RHRSW subsystem otherwise inoperable, restore the inoperable subsystem to OPERABLE sta us with at least one status OPERABLE RHRSW pump within 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> ours and in COLD SHUTDOWN p;;r~?J----trtttt.~.

j)--. following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. )%)~~~/S"" $I"-.i;  ;,. "'-) .....

~~~:---

sD::te 4

f::ws

4. With both RHRSW subsyste nopera e, es restore t

t e a least one subsystem to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN* within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

• Whenever

• Whenever both RHRSW subsystems are inoperable, if unable to attain COLD SHUTDOWN

. as required by this ACTION, maintain reactor coolant temperature as low as practical by use of alternate heat removal methods.

NOV11 661998

_NOV 1998 3/4 7-1 Amendment No. H, G, 92 3e, 16, LIMERICK LIMERICK - UNIT

- UNIT 22

INSERT [SI INSERT raj (RHRSW (RHRSW 3.7.1.1 3.7.1.1.a.3)

.a.3) a) When a) When thethe A

'A' RHRSW subsystem isis inoperable RHRSW subsystem inoperable to to allow allow for repairs of for repairs of the 'A' RHRSW the A RHRSW subsystem subsystem piping, piping, with with Limerick Limerick Generating Generating Station Station Unit Unit 1 1 shutdown, shutdown, reactor reactor vessel head vessel head removed and reactor cavity removed and reactor cavity flooded, flooded, the the 72-hour 72-hour Allowed Allowed Outage Outage Time Time may may be be extended extended to 77 to days once days once every every other other calendar calendar year year with with the following compensator the following y measures compensatory measures established: established:

1)

1) The following systems The systems and and subsystems subsystems will will be protected in be protected accordance with in accordance with applicable applicable station procedures:

• B IB' RHRSW RHRSW subsystem subsystem

• B 'B' ESW loop

• 8 'B' and D '0' RHR subsystems subsystems

• D12,012, D22,022, andand D24 024 4kV4kV buses buses and emergency diesel and emergency diesel generators generators

• Division 2 and Division Division 4 Safeguard DC, and and

2) The 'A'A and B 'B' loop of ESW return flow shall be aligned to the the operable B 'B' RHRSW RHRSW return header only. The ESW return valves to the B 'B' RHRSW return header (Le., HV header (i.e., HV-11-015A 11-01 5A and HV-11-015B)

HV-1 1-0158) will be ely administratively administrativ controlled in the open open position position and and de-energized prior to entering the extended ACT. AOT. The ESW return valves to the A 'A' RHRSW return header (Le., HV-11-011 (i.e., HV-1 A and HV-1 1-011 A 1-011 B) will be HV-11-011 be administrativ administrativelyely controlled in the closed position and de-energized as part of the work boundary.

b) When the 'B' B RHRSW subsystem is inoperable to allow for repairs of the 8 'B' RHRSW subsystem piping, with Limerick Generating Station Unit 1 1 shutdown, reactor vessel head removed and reactor cavity flooded, the 72-hour Allowed Outage Time may be extended to 7 days once every other calendar year with the follOWing compensatory measures established:

following compensatory 1)

1) The following systems and subsystems will be protected in accordance with applicable station procedures:

• • 'A' A RHRSW subsystem

• • 'A' A ESW loop

• • 'A' A and 'C'C RHR subsystems

• • 011,Dli, 021,D21, and and 023D23 4kV buses and emergency diesel generators Division 11 and

• • Division Division 3 Safeguard DC, and and Division 2)

2) The The 'A' A and and 'B'B loop of ESW loop of return flow shall be aligned to the operable 'A' ESW return A RHRSW return return header header only. The ESW only. The return valves to the 'A' ESW return A RHRSW return header (Le., (i.e., HV-HV 11-011 11-01 1A HV-1 1-0118) and HV-11-011 A and will be B) will administratively controlled be administratively controlled in the open position and de-energized de-energized prior prior to entering the to entering the extended ACT. The extended AOT. The ESW returnreturn valves to the 'B' B RHRSW RHRSW return return header header (i.e.,

(Le., HV-1 1-01 HV-11-015A 5A and and HV-1 1-01 HV-11-015B) 5B) will be be administrativ administrativelyely controlled in controlled the closed in the position and closed position and de-energized de-energized as as part the work boundary.

part of the LGS Unit 2 LGSUnit2

PLANT SYSTEMS EMERGENCY EMER6ENCY SERVICE WATER SYSTEM - COMMON SYSTEM

~JnITING LIMITING CON0l!l2N CONDITION FOR OPERATION 3.7.1.2 3 7 1 2 At At least least the following independent emergency service water system loops, loops, with with each loop comprised of:

a.

a. Two .

Two OPERABLE emergency service water pumps, and b.

b. An OPERABLE flow path capable of taking suction from the emergency emergency service service water pumps wet pits which are supplied supplied from the spray spray pond pond or or the cooling tower basin and transferring the water to the associated Unit 22 and co~on connon safety-related safetyrelated equipment, shall be OPERABLE:

a.

a. In In OPERATIONAL CONDITIONS 1, 2, and 3, two loops.

b.

b. In OPERATIONAL CONDITIONS 4, 5, and , *, one loop.

APPLICABILITY:

APPLICABILITY: OPERATIONAL CONDITIONS I, 1, 2, 3, 4, 5, and *..

ACTION:

ACTION

a. In OPERATION CONDITION I,1, 2, or 3:

1. With one emergency service water pump inoperable, restore the inoperable pump to OPERABLE status within 45 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

2. With WIth one emergency service water pump in each loop inoperable, restore at least one inoperable pump to OPERABLE status within 30 days or be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

3. With one emergency service water system loop otherwise inoperable, declare inoperable**, restore the all equipment aligned to the inoperable loop inoperab1e**,

inoperable loop to OPERABLE status with at least one OPERABLE pump within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> o be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SH 0 within the following 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

=#

• When

• When handling irradiated fuel in the secondary containment.

• • The diesel generators may be aligned to the OPERABLE emergency service water system loop provided confirmatory flow testing has been performed. Those diesel generators not aligned to the OPERABLE emergency service water system loop shall be declared inoperable and the actions of 3.8.1.1 taken.

@~~0 jo *1

_1&'998 6, 92 46, Te.

Amendment No. +8.

LIMERICK LIMERICK - UNIT UNIT 22 3/4 7-3

INSERT eel (ESW 37.1 INSERT [Cl (ESW 3.7.1.2.a.3)

.2.a.3)

During the During the extended extended 7-day 7-day Allowed Allowed Outage Outage Time Time (ACT) specified by (AOT) specified by TS LeO 3.7.1.1, TS LCO 3.7.1.1, Action Action a.3.a) a.3.a) or or a.3.b) a.3.b) to to allow allow for for RHRSW RHRSW subsystem subsystem piping piping repairs, repairs, the the 72-hour 72-hour AOT for ACT for one inoperable emergency one inoperable emergency service service water water system system loop loop may may also also be be extended extended to to 7 7 days days for for the same the same 7-day 7-day period.

period.

LGS Unit 2 LGSUnit2

3/4.8 3/4.8 ELECTRICAL ELECTRICA POWER SYSTEMS L POWER SYSTEMS 3/4.8.1 AC.

3/4.8.1. A.C. SOURCES SOURCES A.C. SOURCES A.C. SOURCES . OPERATING OPERATING LIMITING CONDITION LIMITINGC ONDITIOLEFOR OPERATION QR OPERATIOM 3.8.1.1 As 3.8.1.1 As aa minimum, minimum, the the following following A.C. A.C. electrical electrical power power sources sources shall shall bebe OPERABLE:

OPERABLE:

a.

a. Two physically Two physically independent independent circuits circuits between between the the offsite offsite transmission transmission network and network and the the onsite onsite Class Class 1EIE distribution distribution system, system, and and b.

b. Four separate Four separate and and independent independent diesel diesel generators, generators, each each with:

with:

1.

1. AA separate separate day tank tank containing containing aa minimum minimum ofof 250 250 gallons gallons of of fuel, fuel, 2.

2. AA separate separate fuel fuel storage storage system system containing containing aa minimum minimum ofof 33,500 33,500 gallons of gallons of fuel, fuel, and 3.

3. AA separate separate fuel fuel transfer pump.

APPLICABILITY:

APPLICABILLIY: OPERATIONAL OPERATIONAL CONDITION CONDITIONSS 1, 2, and 3.

ACTION:

ACTION:

a.

a. With With one one diesel diesel generator of the above required A.C. electrical power sources sources inoperable, demonstrate the OPERABILI OPERABILITYTY of the remaining A.C.

sources sources by by performing Surveillance Requirement 4.8.1.1.1.a 4.8.l.l.l.a within 24 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> hours and and at 1least east once per 77 days thereafter. If the diesel di esel generator generator became inoperable due to any cause other .than than an inoperable support support system, an independently independently testable component, or preplanned preventive preventive maintenance or testing, demonstrate the OPERABILITY OPERABILITY of the remaining remaining operable diesel generators by performing Surveillance Requirement Requirement 4.8.1.1.2.a.4 for one diesel generator at a time, within 24 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, unless the absence of any potential common-mode common-mode failure for the the remaining diesel diesel generators is determined. Restore the inoperable diesel diesel generator generator to OPERABLE status within 30 days or be in at least HOT HOT SHUTDOWN within SHUTDOWN within the next 12 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN within the following following 24 hours. See See also ACTION e.

b.

b. With With two two diesel diesel generators generators of the above above required A.C. electrical power sources sources inoperable, inoperable, demonstrate demonstrate the the OPERABILITY OPERABILITY of the remaining A.C.

sources sources by by performing performing Surveillance Surveillance Requirement 4.8.1.1.I.a 4.8.1.1.1.a within 11 hour1.273148e-4 days <br />0.00306 hours <br />1.818783e-5 weeks <br />4.1855e-6 months <br /> hour and and at at least least onceonce per per 88 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br /> hours thereafter.

thereafter. If If either either ofof the the diesel diesel generators generators becamebecame inoperable inoperable due to any cause other than an due to any cause other than an inoperable inoperable support support system, system, an an independently independentl y testable testable component, component, or preplanned preplanned preventive preventive maintenance maintenance or or testing, testing, demonstrate demonstrate thethe OPERABILITY OPERABILITY of of the the remaining remaining diesel diesel generators generators by by performing performing Surveillance ReqUirement Surveillance Requirement 4.8.l.1.2.a.4 4.8.1.1.2.a.4 for for one one diesel diesel generator generator at at aa time, time, within within 88 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br />,hours, unless unless the the absence absence of of any any potential common-mode potential common-mode failure failure for for the the remaining remaining diesel diesel generators generators isis determined. Restore at determined. Restore at least least one one of of the the inoperable inoperable diesel diesel generators generators to to OPERABLE within status within OPERABLE status 72 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> hour or or be be inin at at least least HOT HOT SHUTDOWN SHUTDOWN within within the the next next 12 hours and 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and inin COLD COLDWN SHUTDOWN within within the the following following 24 ACTION 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. See also ACTION e.

hours. See also e.

c£:r~;;z5I LIMERICK - UNIT 2 LIMERICK - UNIT ~ 3/4 3/4 8-1 8-1 Amendment No.

Amendment No. +&0,154

INSERT [Dl INSERT [01 (EDGs (EDGs 3.8.1.1.b) 3.8.1.1.b)

• During the During the extended extended 7-day 7-day Allowed Allowed Outage Outage Time Time (ACT) specified by (AOT) specified by TS LeO 3.7.1.1, TS LCO 3.7.1.1, Action a.3.a)

Action a.3.a) or or a.3.b) a.3.b) to to allow allow for for RHRSW RHRSW subsystem subsystem piping piping repairs, repairs, the the 72-hour 72-hour AOT for ACT for two inoperable diesel generators two inoperable diesel generators may may also also be be extended extended to to 7 7 days days for for the the same same 7-day 7-day period.

period.

LGS Unit 2 LGSUnit2

-, ELECTRICA ELECTRICAL POWER SYSTEMS L POWER SYSTEMS LIMITING CONDITION LIMITING CONDITION FOR FOR OPERATION OPERATION (Continued)

(Continued) _

ACTION:

ACTION: (Continued)

(Continued) e.

a. In addition In addition to the ACTIONS to the ACTIONS above:

above:

1.

1. For two for two train train systems, syst.... withwith one one or or sore 80re diesel generators of diesel generators of the above abovi required required AA.C. power sources electrical power C electrical sourcel Inoperable, inoperabll.

verify within 22 hours2.546296e-4 days <br />0.00611 hours <br />3.637566e-5 weeks <br />8.371e-6 months <br /> verify wIthin houri and and at at least lealt once once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> per 12 hour. thereafter thereafter l.ast one that at least of the 0 ... of the required required twotw train SYlt_ subsystem, train system subsyst_.

train. coqonents, train, cOllPon.ntl, and devices is and devices il OPERABLE and its OPERABLE and its associated allociated di **el generator is diesel f s OPERABLE OPERABLE. Otherwise, OtherwiSI. restore ei ther the Nstore either the Inoperable g....r.tor or di.s.l generator inoperabl. diesel or.the hrabl.

the mo ~ system syst. subsystem subsyst.

to an OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> hours oror be be in at least in at HOT least. HOT with1n the next SHUTDOWN within fo 11 ow1 ng 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.

the following next. 12 houri.

houri and 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in 1n COLD SHUTDOWN within COLD SHUTDOWN within

2. For the LPCI systems, syst_s, with two or more die.el generators of th

.... diesel t.he abo"e requi red A. C. electrical above required powr sources elect.ri cal power 1noperab1., yen source. inoperable, veri fy wi thi n 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> within houri and at least once per 12 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter that at .least.

least two of tlw the requi....

required d LPCI systH system subsyltHI. trains, subsystems, t.rat n**

coonents and devices are OPERABLE and its cOllPonent. assoctated diesel tts associated d1 *** 1 g.nerator generator ... is OPERABLE.

OPERABLE. Otherwis.,

Otherwise, be 1n l.a.t HOT SHUTDOWN in at least within t.he S~ within th.

next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and in COLD SHUTDOWN the next. the following 24 hour**

hours.

This ACTION doel does not apply for those sysu. covered in systems cov....d Specifications 3.7.1.1 and 3.7.1.2.

Sp.cificat.ions LIMERICK LIMERICK - UNIT

- UNIT 22 3/4 3/4 8-2 8-2 AUE25 131 lU&2'.

INSERT [El INSERT rEJ (EDGs (EDGs 3.8.1.1.e.1) 3.8.1.1.e.1)

During the During the extended extended 7-day 7-day Allowed Allowed Outage Outage Time Time (ACT)

(AOT) specified by TS specified by LCO 3.7.1 TS LCO .1, 3.7.1.1, Action a.3.a) or a.3.b)

Action a.3.a) or a.3.b) toto allow allow for for RHRSW RHRSW subsystem subsystem piping piping repairs, repairs, the the 72-hour 72-hour ACT AOT may may also be extended to 7 days for the same also be extended to 7 days for the same 7-day 7-day period.

period.

LGS Unit 22 LGS Unit

ATTACHMENT ATTACHME NT 44 License Amendment Request 1 and 2 Limerick Generating Station, Units 1 Docket Nos. 50-352 and 50-353 Proposed Technical Specification Allowed Outage Time Extensions to Support Residual Heat Removal Service Water Maintenance Commitments Summary of Regulatory Commitments

Response

Response to to Request Request for Additional Information for Additional Information Attachment 44 Attachment Docket Docket Nos.

Nos. 50-352 50-352 and and 50-353 50-353 Page 11 of Page of 66

SUMMARY

OF REGULATORY COMMITMENTS COMMITMENTS The following table provides a comparison of the regulatory commitments identified in the original original License Amendment Request License Amendment Request (LAR)

(LAR)

(Reference 1 1 to the letter) and those made within this document. Note that several of of the the original commitments have been eliminated or original commitments have been eliminated or modified modified as as described below in described below in the the table table below. (Any other below. (Any other actions actions discussed discussed in the in the submittal submittal represent represent intended intended or or planned planned actions.

actions. They They are are described described to to the the NRC NRC forfor the the NRC's NRCs information and are information and are not not regulatory regulatory commitments.)

commitments.)

Commitment as listed in LAR, Attachment 1, in 1, Section 4.2 Current Commitment Current Commitment (Based on (Based on Attachment 11 RAt RAt Responses)

Responses)

1. Adequate

1. Adequate staffing staffing will will be be maintained maintained onsite onsite to facilitate timely to facilitate timely response response Deleted. Staffing Deleted. Staffing is is ensured ensured asas part part of of the the normal normal work work control control processes.

processes.

to to unexpected unexpected conditions conditions during during the the period of reliance period of reliance onon the the extended extended See RAI See RAI Response Response Ba. 8a.

AOTs.

ACTs.

2.

2. Besides Besides the the protected protected opposite opposite RHRSW RHRSW subsystems subsystems and and ESW loop ESW loop This compensatory This compensatory measure measure is now is included as now included action in required action as aa required the TS, in the TS, required to be operable by TS, elective maintenance, discretionary regulatory commitment.

no longer a regulatory and therefore, is no commitment. See RAI Response See RAI Response maintenance and testing on all RHR subsystems and EDGs that provide lc. Refer to new proposed TS LCC 1c. LCO 3.7.1.1, a.3.a)1) or Actions a.3.a)1) 3.7.1.1, Actions a.3.b)1) in or a.3.b)1) in partial support to the protected RHRSW subsystem will be suspended Attachment 3.3.

during the period of reliance on the extended AOTs.

during_the_period_of_reliance_on_the_extended_ACTs.

2. (continued) This has been redefined as compensatory measure measure #1#1 as indicated below as indicated below following actions will be taken prior to entry into the Additionally, the follOWing and in RAI Response 8d.

proposed configuration:

1. The following action will be taken prior to entry into the proposed

1. The following action will be taken prior to entry into the proposed

a. Proper standby alignment of the opposite RHRSW subsystem configuration:

will be ensured prior to entry into the AOT to reduce the will be ensured prior to entry into the ACT to reduce the contribution from potential pre-initiator errors. o Proper standby alignment of the operable RHRSW subsystem subsystem will will be ensured prior to entry into the AOT to be ensured prior to entry into the ACT to reduce reduce the the contribution contribution from potential from potential pre-initiator pre-initiator errors.

errors.

Response to Request for Additional Response Additional Information Information Attachment 44 Attachment Nos. 50-352 and 50-353 Docket Nos. 50-353 Page 22 of Page of 66 Commitment as listed in LAR, LAR, Attachment Attachment 1, 1, Section Section 4.24.2 Current Commitment Current Commitment (Based on (Based Attachment 11 RAI on Attachment RAI Responses)

Responses)

2. (continued)

2. This has This redefined as been redefined has been measure #2 compensatory measure as compensatory #2 as indicated below as indicated below

b. Availability of the following equipment

b. equipment will will be be verified:

verified: and in and RAI Response in RAI Response 8d. 8d. ItIt has also been has also modified in been modified content for in content for

• When RHRSW subsystem A is unavailable:

is unavailable: consistency with consistency the new with the new proposed proposed TS LCO 3.7.1 TS LCO .1, Actions 3.7.1.1, a.3.a) and Actions a.3.a) and

- Diesel Generator 11 11 a.3.b).

a.3.b).

- Diesel Generator 21

- Diesel Generator 23 2.

2. Also, the Also, the following actions will following actions will be taken prior be taken prior to entry into to entry the proposed into the proposed

- ESW loop A configuration:

configuration:

- Unit 2 LPCI subsystem A

- Unit 2 LPCI subsystem C

- ** When the When A RHRSW the tAt subsystem is RHRSW subsystem is inoperable inoperable to allow for to allow for repairs repairs

- Unit 2 Core Spray subsystem A

- of RHRSW A the RHRSW of the sUbsystem piping A subsystem Limerick Generating with Limerick piping with Generating Unit 22 shutdown, Station Unit Station shutdown, reactor removed and head removed vessel head reactor vessel and reactor reactor

• When RHRSW subsystem B is unavailable: equipment will flooded, the following equipment cavity flooded, be verified will be as available verified as available Diesel Generator 12 and protected and protected as as defined defined in procedure CP-AA-108-117:

in procedure OP-AA-108-117:

Diesel Generator 14

- Diesel Generator 24 o0 loop A ESW loop ESW

- ESW loop B o0 LPCI subsystems A and Unit 11 LPCI Unit and CC

- Unit 11 LPCI subsystem B o0 Dl 011,1, Dl 013,3, and and D23023 4kV buses and 4kV buses emergency diesel and emergency diesel

- Unit 11 LPCI subsystem 0 D generators generators

- Unit 11 Core Spray subsystem B o0 Division 11 and Division 33 Safeguard Unit 11 Division Safeguard DC DC Elective maintenance, discretionary maintenance and testing on ** When the tAt A RHRSW subsystem is inoperable to is inoperable allow for to allow for repairs repairs the above listed equipment will be suspended during the period of the RHRSW A subsystem piping piping with Limerick Generating Generating of reliance on the extended AOTs.

ACTs. Station Unit 11 shutdown, reactor vessel head removed and head removed and reactor reactor cavity flooded, the following equipment will be verified as available be verified available and protected as defined in procedure OP-AA-108-l17: OP-AA-108-117:

0o ESW loop A 0o Unit 2 LPCI subsystems A and C 0o 011, D21, and D23 Dli, 021, 023 4kV buses and emergency diesel diesel generators 0o Unit 2 Division 1 1 and Division 3 Safeguard DC (continued)

Information Response to Request for Additional Information Attachment 44 Attachment Docket Nos. 50-352 and 50-353 Page 33 of Page of 66 Commitment as listed in LAR, Attachment 1, 1, Section Section 4.2 Current Commitment Current Commitment (Based_on_Attachment_1_RAI_Responses)

(Based on Attachment 1 RAJ Responses)

(continued)

(continued)

• When the When IBI RHRSW the B subsystem is RHRSW subsystem is inoperable inoperable toto allow for repairs allow for repairs the RHRSW B of the B subsystem subsystem piping piping with Limerick Generating with Limerick Generating Station Unit Station Unit 22 shutdown, shutdown, reactor reactor vessel removed and head removed vessel head and reactor reactor cavity flooded, the the following equipment will be equipment will be verified as available verified as available and protected as as defined defined in procedure OP-AA-108-1 in procedure OP-AA-108-117: 17:

o0 loop B ESW loop B o0 Unit 11 LPCI Unit LPCI subsystems B and D Band D o0 D12, D14, and D24 4kV and D24 4kV buses buses and emergency diesel and emergency diesel generators o0 Unit 11 Division Safeguard DC and Division 4 Safeguard Division 22 and DC

• • When the B IBI RHRSW subsystem is RHRSW subsystem is inoperable inoperable to allow for to allow for repairs repairs of the RHRSW B subsystem piping piping with Limerick Generating Generating Station Unit 1 1 shutdown, reactor vessel head removed removed and and reactor reactor cavity flooded, the following equipment will be verified as available be verified as available and protected as defined in procedure OP-AA-1 OP-AA-1 08-117:

0o ESW loop B 0o Unit 2 LPCI subsystems B and D Band D 0o D12, D22, and D24 4kV buses and emergency diesel generators 0o Unit 2 Division 2 and Division 4 Safeguard DC 3.

3. Activities Activities that that adversely adversely affect affect risk risk exposure exposure will be be prohibited in in the This compensatory measure #3 has been redefined as indicated below and LGS LGS 500kV 500kV and and 220kV 220kV electrical electrical switchyards switchyards to minimize minimize the possibility in RAI Response 8e.

of of an an induced induced LOOP LOOP and and loss loss of of power power to to protected protected equipment during the period of reliance on the extended AOTs.

the period of reliance on the extended ACTs. 3. Activities in the switchyard that adversely affect risk exposure are those that have the potential to cause a total loss of offsite power. Therefore, the at-power unit switchyard will be protected in its entirety and equipment in the outage unit switchyard supporting operability of its offsite source will be protected during the RHRSW subsystem piping equipment will be protected as defined in procedure OP-This equipment repairs. This repairs. OP AA-108-117 AA-1 08-117 and and in accordance with station procedure OP-LG-108-117.

OP-LG-1 08-117.

controlled via the special procedure developed specifically This will be controlled This to Qovern to plant operation while in the extended AOTs.

govern plant ACTs.

Response to Request for Additional Information Information Attachment 44 Attachment Docket Nos. 50-352 and 50-353 Page 4of Page 40f6 6 Commitment as listed in LAR, Attachment 1, Section 4.2 1, Section 4.2 Current Current Commitment Commitment (Based on (Based Attachment 11 RAt on Attachment RAJ Responses)

Responses)

4. Operational Risk Activities will be restricted during during the extended extended ACTs.

AOTs. This compensatory measure This measure has been redefined has been redefined as indicated below as indicated and in below and in Station Vice-President approval will be required to perform emergent emergent RAI RAI Response Bf. 8f.

operational risk activities during the period of reliance on the extended AOTs.

ACTs. 4.

4. Operational Risk Operational Activities (ORA5),

Risk Activities (ORAs), as defined in as defined in procedure procedure WC-AA WC-AA-104, involve 104, activities on involve activities on risk significant systems risk significant systems that that have have thethe potential potential derate the to derate plant, i.e.,

the plant, i.e., cause loss of cause aa loss of planned generation. Typical planned generation. Typical ORAs involve:

involve: an activity that an activity that could cause equipment could cause actuations that equipment actuations that could cause loss of cause loss of planned instrument, fuse, generation; instrument, planned generation; fuse, or or circuit circuit board removal/installation; an board removal/installation; activity that an activity that will cause aa 1/2 will cause scram or 112 scram or 1/2Y2 pressurization of trip; pressurization trip; of common sensing lines; instrument sensing common instrument placing of lines; placing of jumpers or jumpers lifting energized or lifting energized leads;leads; anan activity that could activity that cause vibration could cause vibration or impact near operational risk sensitive near operational equipment, etc.

sensitive equipment, etc. Such Such activities will activities prohibited on be prohibited will be on the online unit the online unit during during the RHRSW piping the RHRSW piping repairs. Exceptions Exceptions to to this this must must be be approved approved by the senior by the senior plant plant management. This will management. be controlled will be controlled as as part of the part of special procedure the special procedure developed specifically specifically to govern plant to govern while in operation while plant operation the extended in the extended ACTs.

AOTs.

5. The extended weather forecast will be examined to ensure severe No change to this compensatory measure. measure. This This will be controlled will be controlled via via the the weather conditions that would threaten the loss of offsite power are notnot developed specifically special procedure developed specifically to to govern operation while plant operation govern plant while in in AOT. In the event of an unforeseen predicted prior to entry into the ACT. the extended ACTs.

AOTs.

severe weather condition due to rapidly changing conditions, such as severe high winds, a briefing with crew operators will be performed to reinforce operator actions and responses in the event of a loss of offsite power (E-10/20).

power_(E-10/20).

6. Shift briefs will be performed to reinforce other potentially important No change to this compensatory measure. measure. This This will will be controlled via be controlled via the the operator actions associated with the performance of the extended ACT AOT special procedure developed specifically to govern plant to govern operation while plant operation while in in (i.e., operator actions to refill the condensate storage tank (CST), the extended ACTs.

AOTs.

operator actions to vent containment, operator actions to maximize control rod drive (CRD) injection to the vessel, and operator actions to support continued use of feedwater and condensate post-trip as necessary and if available). Additionally, during the 'A'A RHRSW subsystem outage, a shift brief on alternate remote shutdown operations will be performed since some of the normally operated equipment_from_the_remote_shutdown_panel_will_not_be_available.

equipment from the remote shutdown panel will not be available.

Response to Request Request for Additional Additional Information Information Attachment 44 Attachment Docket Nos. Nos. 50-352 andand 50-353 50-353 Page 55 of Page of 66 Commitment as listed in in LAR, LAR, Attachment Attachment 1, 1, Section Section 4.24.2 Current Commitment Current Commitment (Based on (Based on Attachment Attachment 11 RAI RAJ Responses)

Responses) pre-job walkdowns

7. Shift briefs and pre-job walkdowns to to reduce reduce andand manage manage transient transient This compensatory This compensatory measuremeasure has been redefined has been as indicated redefined as below and indicated below and inin entrance into combustibles prior to entrance into the the extended extended ACT AOT will will be used to be used to RAI Response RAI Response 8g. 8g.

about the increased alert the staff about increased sensitivity sensitivity to in the to fires in the following following areas during the extended RHRSW RHRSW outage Additionally, any outage windows. Additionally, any 7.

7. Unattended transient Unattended combustibles and transient combustibles and hot work will hot work will be prohibited inin be prohibited hot work activities in in the following following areas willwill be be prohibited during the prohibited during the the the areas listed below areas listed during the below during the extended AOT. This extended ACT. This will be controlled will be controlled time within the extended RHRSW ACT. AOT. via the special via the special procedure developed specifically procedure developed specifically to govern plant to govern plant while in operation while operation the extended in the extended ACTs.

AOTs.

For the A 'A' RHRSW subsystem outage window: window:

Unit 1 1 For an A For an RHRSW subsystem

'AI RHRSW outage window:

subsystem outage window:

.* Fire Area 15, 15, Unit Unit 11 Division safeguard 4kV Division 22 (D12) safeguard 4kV switchgear switchgear ** Fire Fire Area 15, Unit Area 15, Division 22 (D12)

Unit 11 Division safeguard 4kV (D12) safeguard 4kV room switchgear room switchgear room

• • Fire Area 24, Main Control Control Room ** Fire Fire Area Area 17, Division 22 (D22)

Unit 22 Division 17, Unit safeguard 4kV (D22) safeguard 4kV

• • Fire Area 25, Auxiliary Equipment RoomRoom switchgear switchgear room room

• • Fire Area 24, Fire Area Control Room Main Control 24, Main Room (ECCS panel l0-C601 (ECCS BB panel 10-C601 Unit 2 (Bay A, (Bay A, B))

B))

• • Fire Area 17,17, Unit 2 Division 2 (D22) safeguard 4kV switchgear switchgear ** Fire Fire Area Area 24, Control Room Main Control 24, Main (ECCS BB panel Room (ECCS panel 20-C601 20-C601 room (Bay A, (Bay A, B))

B))

• • Fire Area 24, Main Control Room ** Fire Fire Area 25, Auxiliary Area 25, Equipment Room Auxiliary Equipment Room

• • Fire Area 25, Auxiliary Equipment Room For an For an B RHRSW subsystem IB' RHRSW outage window:

subsystem outage window:

For the 'B' B RHRSW subsystem outage window: ** FireFire Area Area 13, 13, Unit Division 11 (Dl Unit 11 Division (D11) safeguard 4kV

1) safeguard 4kV Unit 1 1 switchgear room switchgear room

• . Fire Area 13, Unit 1 1 Division 1 (D11) safeguard 4kV switchgear 1 (Dli) ** Fire Area 19, Fire Area 19, Unit Division 11 (D21)

Unit 22 Division safeguard 4kV (D21) safeguard 4kV room switchgear switchgear room room

• Fire Area 24, Main Control Room ** FireFire Area 24, Main Area 24, Control Room Main Control (ECCS A Room (ECCS A panel panel l0-C601 10-C601

• • Fire Area 25, Auxiliary Equipment Room (Bay C, (Bay D, E, C, D, E, F))

F))

• • Fire Area 26, Remote Shutdown Panel ** Fire Area 24, Fire Area 24, Main Main Control Room (ECCS Control Room (ECCS A A panel panel 20-C601 20-C601 (Bay C, (Bay C, D, D, E, E, F))

F))

Unit 2 ** FireFire Area Auxiliary Equipment 25, Auxiliary Area 25, Equipment RoomRoom

• Fire Area 19, Unit 2 Division 1 1 (D21) safeguard 4kV switchgear ** Fire Area 26, 26, Remote Shutdown Panel Remote Shutdown Panel room

• Fire Area 24, Main Control Room

• Fire Area 25, Auxiliary Equipment Room

• Fire Area 26, Remote Shutdown Panel

Response to Request for Additional Information Attachment 44 Attachment Docket Nos. 50-352 and 50-353 Page 660f6 Page of 6 Commitment as listed in LAR, Attachment 1, Section 4.2 Commitment Current Commitment (Based on Attachment 11 RAI RAJ Responses)

Responses) 8a.

Ba. When the IA AI RHRSW return header is undergoing maintenance, the A IAI This compensatory measure is is now now included included as as a required action action in in TS, TS, and and and IBI I B loop of ESW return flow shall be aligned to the operable BIB therefore, is no longer a regulatory commitment.

commitment. See See RAI RAI Response Response lc,1c.

RHRSW return header only. The ESW return valves (i.e., (Le., HV-1 HV-11-015A 1 -01 5A LCD 3.7.1 Refer to TS LCO .1,, Action a,3.a)2) 3.7.1.1 a.3.a)2) in in Attachment Attachment 3. 3.

HV-1 1-0156) to the IB and HV-11-015B) BI RHRSW return header will be administratively controlled in the open position and de-energized prior to entering the extended AOT. HV-1 1-011 A and ACT. The ESW return valves, HV-11-011A HV-1 1-011 B, to the IA HV-11-011 AI RHRSW return header will be administratively controlled in the closed position and de-energized as part of the work boundary. (See Item b. in the review of plant impacts described in Section_4.1.)

Section 4.1.)

8b. When the IB BI RHRSW return header is undergoing maintenance, the A IN This compensatory measure measure is is now now included as aa required action included as in TS, action in TS, and and and IBI B loop of ESW return flow shall be aligned to the operable AIAI therefore, is no longer longer a regulatory regulatory commitment.

commitment. See See RAI RAJ Response Response lc.

1c.

RHRSW return header only. The ESW return valves (i.e., (Le., HV-1 1-011 A HV-11-011 Refer to TS LCO LCD 3.7.1.1, 3.7.1.1, Action a.3.b)2) a.3.b)2) in in Attachment Attachment 3. 3.

HV-1 1-011 B) to the IA and HV-11-011 AI RHRSW return header will be administratively adm inistratively controlled in the open position and de-energized prior to entering the extended AOT. ACT. The ESW return valves, HV-1 1 -015A and HV-11-015A HV-1 1-015B, to the IB HV-11-015B, BI RHRSW return header will be administratively controlled in the closed position and de-energized as part of the work boundary. (See Item b. in the review of plant impacts described in Section_4.1.)

Section 4.1.)