RS-22-061, Request for License Amendment to Adopt TSTF-269, Revision 2, Allow Administrative Means of Position Verification for Locked or Sealed Valves

Request for License Amendment to Adopt TSTF-269, Revision 2, Allow Administrative Means of Position Verification for Locked or Sealed Valves

ML22144A236
Person / Time
Site:	Clinton
Issue date:	05/24/2022
From:	Simpson P Constellation Energy Generation
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-22-061
Download: ML22144A236 (21)

Text

4300 Winfield Road Warrenville, IL 60555 630 657 2000 Office RS-22-061 10 CFR 50.90 May 24, 2022 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 NRC Docket No. 50-461

Subject:

Request for License Amendment to Adopt TSTF-269, Revision 2, "Allow Administrative Means of Position Verification for Locked or Sealed Valves" In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Constellation Energy Generation, LLC (CEG) requests an amendment to Facility Operating License No. NPF-62 for Clinton Power Station (CPS), Unit 1. The proposed change is consistent with NRC-approved Technical Specification Task Force (TSTF)

Traveler 269-A, Revision 2, "Allow Administrative Means of Position Verification for Locked or Sealed Valves." Specifically, the proposed change modifies Technical Specifications (TS) requirements for repetitive verification of the status of locked, sealed, or secured components to allow the verification to be by administrative means.

This request is subdivided as follows.

• Attachment 1 provides a description and evaluation of the proposed change.

• Attachment 2 provides a markup of the affected TS pages.

• Attachment 3 provides a markup of the affected TS Bases pages. The TS Bases pages are provided for information only and do not require NRC approval.

The proposed change has been reviewed by the Plant Operations Review Committee in accordance with the requirements of the CEG Quality Assurance Program.

CEG requests approval of the proposed change by May 24, 2023. Once approved, the amendment will be implemented within 60 days. This implementation period will provide adequate time for the affected station documents to be revised using the appropriate change control mechanisms.

In accordance with 10 CFR 50.91, "Notice for public comment; State consultation,"

paragraph (b), CEG is notifying the State of Illinois of this application for license amendment by transmitting a copy of this letter and its attachments to the designated State Official.

May 24, 2022 U.S. Nuclear Regulatory Commission Page 2 There are no regulatory commitments contained in this letter. Should you have any questions concerning this letter, please contact Mr. Kenneth M. Nicely at (630) 657-2803.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 24th day of May 2022.

Respectfully, Patrick R. Simpson Sr. Manager Licensing Constellation Energy Generation, LLC Attachments:

1. Evaluation of Proposed Change

2. Markup of Technical Specifications Pages

3. Markup of Technical Specifications Bases Pages (For Information Only) cc: NRC Regional Administrator, Region III NRC Senior Resident Inspector - Clinton Power Station Illinois Emergency Management Agency - Division of Nuclear Safety

ATTACHMENT 1 Evaluation of Proposed Change 1.0

SUMMARY

DESCRIPTION 2.0 DETAILED DESCRIPTION 2.1 Description of Proposed Change 2.2 Description of Variances

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 No Significant Hazards Consideration 4.4 Conclusions

6.0 REFERENCES

Page 1

ATTACHMENT 1 Evaluation of Proposed Change 1.0

SUMMARY

DESCRIPTION In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Constellation Energy Generation, LLC (CEG) requests an amendment to Facility Operating License No. NPF-62 for Clinton Power Station (CPS), Unit 1. The proposed change is consistent with NRC-approved Technical Specification Task Force (TSTF) Traveler 269-A, Revision 2, "Allow Administrative Means of Position Verification for Locked or Sealed Valves" (i.e., Reference 1). Specifically, the proposed change modifies Technical Specifications (TS) requirements for repetitive verification of the status of locked, sealed, or secured components to allow the verification to be by administrative means. The NRC approved TSTF-269-A, Revision 2, in Reference 2.

2.0 DETAILED DESCRIPTION 2.1 Description of Proposed Change The proposed change modifies TS 3.6.1.3, "Primary Containment Isolation Valves (PCIVs),"

TS 3.6.4.2, "Secondary Containment Isolation Dampers (SCIDs)," and TS 3.6.5.3, "Drywell Isolation Valves." These specifications require penetration flow paths with inoperable isolation devices to be isolated and periodically verified to be isolated. Consistent with TSTF-269-A, Revision 2, notes are proposed to be added to TS 3.6.1.3 Required Actions A.2 and D.2, TS 3.6.4.2 Required Action A.2, and TS 3.6.5.3 Required Action A.2 to allow isolation devices that are locked, sealed, or otherwise secured to be verified using administrative means.

A markup of the proposed TS changes is provided in Attachment 1. Attachment 2 provides a markup of the affected TS Bases pages. The TS Bases pages are provided for information only and do not require NRC approval.

2.2 Description of Variances CEG is proposing the following variations from the TS changes described in TSTF-269-A.

• The CPS TS do not contain a Condition equivalent to TS 3.6.1.3 Condition C in TSTF-269-A. Therefore, that change is not applicable to CPS.

• TSTF-269-A identifies a change to TS 3.6.1.3 Required Action E.2. The equivalent Required Action in the CPS TS is D.2.

These variations do not affect the applicability of TSTF-269-A to CPS.

3.0 TECHNICAL EVALUATION

The purpose of the periodic verification that a penetration with an inoperable isolation device continues to be isolated is to detect and correct inadvertent repositioning of the isolation device.

However, the function of locking, sealing, or securing an isolation device is to ensure that the device is not inadvertently repositioned. Therefore, it is sufficient to assume that the initial Page 2

ATTACHMENT 1 Evaluation of Proposed Change establishment of component status (e.g., isolation devices closed) was performed correctly and subsequent periodic re-verification need only be a verification of the administrative control that ensures that the component remains in the required state. It is unnecessary and undesirable to remove the lock, seal, or other means of securing the component solely to perform an active verification of the required state as it would increase the chance of mispositioning due to the frequent manipulation.

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria The proposed change has been evaluated to determine whether applicable regulations and requirements continue to be met. The regulations of 10 CFR 50.36, "Technical specifications,"

establish the requirements related to the content of the TS. Paragraph (c) of 10 CFR 50.36 states:

When a limiting condition for operation of a nuclear reactor is not met, the licensee shall shut down the reactor or follow any remedial action permitted by the technical specifications until the condition can be met.

There is no regulatory requirement that specifies what remedial actions are to be taken when a limiting condition for operation is not met. The proposed change removes operational restrictions not needed for safety. The proposed change is consistent with Reference 3.

4.2 Precedent An example of a plant-specific NRC approval of the changes in TSTF-269-A, Revision 2, is Brunswick Steam Electric Plant, Units 1 and 2, Amendment Nos. 296 and 324, dated November 21, 2019 (i.e., Reference 4).

4.3 No Significant Hazards Consideration In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Constellation Energy Generation, LLC (CEG) requests an amendment to Facility Operating License No. NPF-62 for Clinton Power Station (CPS), Unit 1. The proposed change is consistent with NRC-approved Technical Specification Task Force (TSTF) Traveler 269-A, Revision 2, "Allow Administrative Means of Position Verification for Locked or Sealed Valves." Specifically, the proposed change modifies Technical Specifications (TS) requirements for repetitive verification of the status of locked, sealed, or secured components to allow the verification to be by administrative means.

According to 10 CFR 50.92, "Issuance of amendment," paragraph (c), a proposed amendment to an operating license involves no significant hazards consideration if operation of the facility in accordance with the proposed amendment would not:

Page 3

ATTACHMENT 1 Evaluation of Proposed Change (1) Involve a significant increase in the probability or consequences of any accident previously evaluated; or (2) Create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) Involve a significant reduction in a margin of safety.

CEG has evaluated the proposed change, using the criteria in 10 CFR 50.92, and has determined that the proposed change does not involve a significant hazards consideration. The following information is provided to support a finding of no significant hazards consideration.

1. Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No The proposed change modifies TS 3.6.1.3, "Primary Containment Isolation Valves (PCIVs)," TS 3.6.4.2, "Secondary Containment Isolation Dampers (SCIDs)," and TS 3.6.5.3, "Drywell Isolation Valves." These specifications require penetration flow paths with inoperable isolation devices to be isolated and periodically verified to be isolated.

Consistent with TSTF 269 A, Revision 2, notes are proposed to be added to TS 3.6.1.3 Required Actions A.2 and D.2, TS 3.6.4.2 Required Action A.2, and TS 3.6.5.3 Required Action A.2 to allow isolation devices that are locked, sealed, or otherwise secured to be verified using administrative means.

The proposed change does not affect any plant equipment, test methods, or plant operation, and is not an initiator of any analyzed accident sequence. The inoperable containment penetrations will continue to be isolated, and hence perform their isolation function. Operation in accordance with the proposed TSs will ensure that analyzed accidents will continue to be mitigated as previously analyzed.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?

Response: No The proposed change does not involve a physical alteration to the plant (i.e., no new or different type of equipment will be installed) or a change to the methods governing normal plant operation. Furthermore, the proposed change does not alter the assumptions made in the safety analysis.

Therefore, the proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.

Page 4

ATTACHMENT 1 Evaluation of Proposed Change

3. Does the proposed change involve a significant reduction in a margin of safety?

Response: No The proposed change will not affect operation of plant equipment or the function of any equipment assumed in the accident analysis. Affected containment penetrations will continue to be isolated as required by the existing TS.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above evaluation, CEG concludes that the proposed change presents no significant hazards consideration under the standards set forth in 10 CFR 50.92, paragraph (c),

and accordingly, a finding of no significant hazards consideration is justified.

4.4 Conclusions In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or the health and safety of the public.

5.0 ENVIRONMENTAL CONSIDERATION

CEG has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, "Standards for Protection Against Radiation." However, the proposed amendment does not involve: (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluent that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22, "Criterion for categorical exclusion; identification of licensing and regulatory actions eligible for categorical exclusion or otherwise not requiring environmental review,"

paragraph (c)(9). Therefore, pursuant to 10 CFR 51.22, paragraph (b), no environmental impact statement or environmental assessment needs to be prepared in connection with the proposed amendment.

6.0 REFERENCES

1. TSTF-269-A, Revision 2, "Allow Administrative Means of Position Verification for Locked or Sealed Valves"

2. Letter from W. D. Beckner (U.S. NRC) to J. Davis (Nuclear Energy Institute), dated July 26, 1999 Page 5

ATTACHMENT 1 Evaluation of Proposed Change

3. NUREG-1434, Revision 5.0, "Standard Technical Specifications, General Electric BWR/6 Plants," dated September 2021

4. Letter from A. Hon (U.S. NRC) to J. A. Krakuszeski (Duke Energy Progress, LLC),

"Brunswick Steam Electric Plant, Units 1 and 2 - Issuance of Amendment Nos. 296 and 324 to Adopt Technical Specification Task Force Traveler TSTF-269-A, Revision 2,

'Allow Administrative Means of Position Verification for Locked or Sealed Valves' (EPID L-2018-LLA-0594)," dated November 21, 2019 Page 6

ATTACHMENT 2 Markup of Technical Specifications Pages Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 REVISED TECHNICAL SPECIFICATIONS PAGES 3.6-11 3.6-13 3.6-48 3.6-62

PCIVs 3.6.1.3 ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME A. (continued) A.2 --------NOTE--------- NOTES

1. Isolation devices in high radiation areas may be verified by use of administrative means.

Verify the affected Once per

2. Isolation devices that penetration flow path 31 days are locked, sealed, or is isolated. following isolation for otherwise secured may isolation be verified by use of devices outside administrative means. primary containment, drywell, and steam tunnel AND Prior to entering MODE 2 or 3 from MODE 4, if not performed within the previous 92 days, for isolation devices inside primary containment, drywell, or steam tunnel (continued)

CLINTON 3.6-11 Amendment No. 238

PCIVs 3.6.1.3 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME D. One or more D.1 Isolate the affected 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> penetration flow paths penetration flow with one or more path by use of at OR primary containment least one closed and purge valves not de-activated In accordance within purge valve automatic valve, with the Risk leakage limits. closed manual valve, Informed or blind flange. Completion Time Program AND NOTES D.2 ---------NOTE--------

Isolation devices in

1. high radiation areas may be verified by use of administrative means.

Verify the affected Once per 31

2. Isolation devices that penetration flow path days following are locked, sealed, or is isolated. isolation for isolation otherwise secured may devices outside be verified by use of primary administrative means. containment AND Prior to entering MODE 2 or 3 from MODE 4 if not performed within the previous 92 days for isolation devices inside primary containment AND (continued)

CLINTON 3.6-13 Amendment No. 238

SCIDs 3.6.4.2 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME A. One or more A.1 Isolate the affected 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> penetration flow paths penetration flow path with one SCID by use of at least inoperable. one closed and de-activated automatic damper, closed manual valve or damper, or blind flange.

AND NOTES A.2 --------NOTE---------

Isolation devices in

1. high radiation areas may be verified by

2. Isolation devices that use of administrative are locked, sealed, or means.

otherwise secured may be verified by use of Verify the affected Once per administrative means. penetration flow path 31 days is isolated.

B. One or more B.1 Isolate the affected 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> penetration flow paths penetration flow path with two SCIDs by use of at least inoperable. one closed and de-activated automatic damper, closed manual valve or damper, or blind flange.

C. Required Action and C.1 Be in MODE 3. 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> associated Completion Time of Condition A AND or B not met in MODE 1, 2, or 3. C.2 Be in MODE 4. 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> (continued)

CLINTON 3.6-48 Amendment No. 95

Drywell Isolation Valves 3.6.5.3 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME A. One or more A.1 Isolate the affected 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> penetration flow paths penetration flow path with one required by use of at least OR drywell isolation one closed and de-valve inoperable. activated automatic In accordance valve, closed manual with the Risk valve, blind flange, Informed or check valve with Completion Time flow through the Program valve secured.

AND NOTES A.2 --------NOTE---------

Isolation devices in

1. high radiation areas may be verified by

2. Isolation devices that use of administrative means.

are locked, sealed, or ---------------------

otherwise secured may be verified by use of Verify the affected Prior to penetration flow path entering MODE 2 administrative means. is isolated. or 3 from MODE 4, if not performed within the previous 92 days (continued)

CLINTON 3.6-62 Amendment No. 238

ATTACHMENT 3 Markup of Technical Specifications Bases Pages Clinton Power Station, Unit 1 Facility Operating License No. NPF-62 REVISED TECHNICAL SPECIFICATIONS BASES PAGES B 3.6-18 B 3.6-19 B 3.6-20 B 3.6-21 B 3.6-91 B 3.6-117 B 3.6-118

No changes to this page. PCIVs B 3.6.1.3 BASES ACTIONS option of operating the IFTS for testing, maintenance, or (continued) movement of new (non-irradiated) fuel to the upper containment pool when primary containment operability is required. Requiring the fuel building fuel transfer pool water to be t el. 753 ft. ensures a sufficient depth of water over the highest point on the transfer tube outlet valve in the fuel building fuel transfer pool to prevent direct communication between the containment building atmosphere and the fuel building atmosphere via the inclined fuel transfer tube. Because excessive leakage of water from the upper containment pool through the open IFTS penetration would result in the inability to provide the required volume of water to the suppression pool in an upper pool dump, an administrative control was required to ensure the upper pool volume meets the design requirements. In addition to the dedicated individual stationed at the IFTS controls, the required administrative controls involved the installation of the Steam Dryer Pool to Reactor Cavity Pool gate with the seal inflated and a backup air supply provided. Since the IFTS transfer tube drain line does not have the same water level as the transfer tube, and the motor-operated drain valve remains open when the carriage is in the lower pool, administrative controls are required to ensure the drain line flow path is quickly isolated in the event of a LOCA.

In this instance, administrative controls of the IFTS transfer tube drain line isolation valve(s) include stationing a dedicated individual, who is in continuous communication with the control room, at the IFTS control panel in the fuel building. This individual will initiate closure of the IFTS transfer tube drain line motor-operated isolation valve (1F42-F003), the IFTS transfer tube drain line manual isolation valve (1F42-F301), and the IFTS drain line test connection isolation valve (1F42-F305) if a need for primary containment isolation is indicated. The pressure integrity of the IFTS transfer tube, the seal created by water depth of the fuel building transfer pool, and the administrative control of the drain line flow path create an acceptable barrier to prevent the post-accident containment building atmosphere from leaking into the fuel building.

The total time per operating cycle that the blind flange may be open in Modes 1, 2, and 3 without affecting plant risk levels is 40 days.

A.1 and A.2 With one or more penetration flow paths with one PCIV inoperable except for inoperability due to leakage not within a limit specified in an SR to this LCO, the affected penetration flow path must be isolated. The method of isolation must include the use of at least one isolation barrier that cannot be adversely affected by a single active failure. Isolation barriers that meet this criterion are a closed and de-activated automatic valve, a closed manual valve, a blind flange, and a check valve with flow through (continued)

CLINTON B 3.6-18 Revision No. 20-2

PCIVs B 3.6.1.3 BASES ACTIONS A.1 and A.2 (continued) the valve secured. For penetrations isolated in accordance with Required Action A.1, the device used to isolate the penetration should be the closest one available to the primary containment. The Required Action must be completed within the 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> Completion Time (8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> for main steam lines and 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for instrument line excess flow check valves (EFCVs)) or in accordance with the Risk Informed Completion Time Program. The specified time period of 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> is reasonable considering the time required to isolate the penetration and the relative importance of supporting primary containment OPERABILITY during MODES 1, 2, and 3.

For main steam lines, an 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time is allowed.

Alternatively, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

The Completion Time of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> for the main steam lines allows a period of time to restore the MSIVs to OPERABLE status given the fact that MSIV closure will result in isolation of the main steam line(s) and a potential for plant shutdown. For EFCVs, a 12 hour1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> Completion Time is allowed. Alternatively, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program. The Completion Time of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> for EFCVs allows a period of time to restore the EFCVs to OPERABLE status given the fact that these valves are associated with instrument lines which are of small diameter and thus represent less significant leakage paths.

For affected penetrations that have been isolated in Note 2 applies to accordance with Required Action A.1, the affected penetration flow path must be verified to be isolated on a isolation devices that periodic basis. This is necessary to ensure that primary are locked, sealed, or containment penetrations required to be isolated following otherwise secured in an accident, and no longer capable of being automatically isolated, will be isolated should an event occur. This position and allows Required Action does not require any testing or device these devices to be manipulation. Rather, it involves verification that those devices outside primary containment, drywell, and steam verified closed by use of tunnel and capable of being mispositioned are in the correct administrative means. position. The Completion Time for this verification of "once per 31 days following isolation for isolation devices Allowing verification by outside primary containment, drywell, and steam tunnel," is administrative means is appropriate because the devices are operated under administrative controls and the probability of their considered acceptable, misalignment is low. For devices inside primary since the function of containment, drywell, or steam tunnel, the specified time locking, sealing, or period of "prior to entering MODE 2 or 3 from MODE 4, if not performed within the previous 92 days," is based on securing components is engineering judgment and is considered reasonable in view of to ensure that these the inaccessibility of the devices and the existence of other administrative controls ensuring that device devices are not misalignment is an unlikely possibility. two Notes. Note 1 inadvertently Required Action A.2 is modified by a Note that applies to repositioned. isolation devices located in high radiation areas and allows them to be verified by use of administrative means.

Allowing verification by administrative means is considered acceptable, since access to these areas is typically restricted. Therefore, the probability of misalignment; once they have been verified to be in the proper position, is low.

(continued)

CLINTON B 3.6-19 Revision No. 21-7

PCIVs No changes to this page. B 3.6.1.3 BASES ACTIONS B.1 (continued)

With one or more penetration flow paths with two PCIVs inoperable, except due to leakage not within limits, either the inoperable PCIVs must be restored to OPERABLE status or the affected penetration flow path must be isolated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The method of isolation must include the use of at least one isolation barrier that cannot be adversely affected by a single active failure. Isolation barriers that meet this criterion are a closed and de-activated automatic valve, a closed manual valve, and a blind flange.

The 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Completion Time is consistent with the ACTIONS of LCO 3.6.1.1.

C.1 With the secondary containment bypass leakage rate, hydrostatic leakage rate, or MSIV leakage rate not within limit, the assumptions of the safety analysis may not be met. Therefore, the leakage must be restored to within limit within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. Restoration can be accomplished by isolating the penetration that caused the limit to be exceeded by use of one closed and de-activated automatic valve, closed manual valve, or blind flange. When a penetration is isolated, the leakage rate for the isolation penetration is assumed to be the actual pathway leakage through the isolation device. If two isolation devices are used to isolate the penetration, the leakage rate is assumed to be the lesser actual pathway leakage of the two devices.

The 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> Completion Time is reasonable considering the time required to restore the leakage by isolating the penetration and the relative importance to the overall containment function.

D.1, D.2, and D.3 In the event one or more primary containment purge valves are not within the purge valve leakage limits, purge valve leakage must be restored to within limits or the affected penetration must be isolated. The method of isolation must be by the use of at least one isolation barrier that cannot be adversely affected by a single active failure. Isolation barriers that meet this criterion are a closed and de-activated automatic valve, closed manual valve, and blind flange. If a purge valve with resilient seals is utilized to satisfy Required Action D.1, it must have been demonstrated to meet the leakage requirements of SR 3.6.1.3.5. The specified Completion Time is reasonable, considering that one primary containment purge valve remains closed (refer to the requirements of SR 3.6.1.3.1; if this requirement is not met, entry into Condition A and B, as appropriate, would also be required), so that a gross breach of primary containment does not exist. Alternatively, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

(continued)

CLINTON B 3.6-20 Revision No. 21-7

PCIVs B 3.6.1.3 BASES ACTIONS D.1, D.2, and D.3 (continued)

In accordance with Required Action D.2, this penetration flow path following isolation must be verified to be isolated on a periodic basis. The periodic verification is necessary to ensure that primary containment penetrations Required Action D.2 is required to be isolated following an accident, which are no longer capable of being automatically isolated, will be modified by two Notes. isolated should an event occur. This Required Action does Note 1 applies to not require any testing or valve manipulation. Rather, it isolation devices located involves verification that those isolation devices outside primary containment and potentially capable of being in high radiation areas mispositioned are in the correct position. For the and allows these devices isolation devices inside primary containment, the time to be verified closed by period specified as "prior to entering MODE 2 or 3, from MODE 4 if not performed within the previous 92 days" is use of administrative based on engineering judgment and is considered reasonable means. Allowing in view of administrative controls that will ensure that isolation device misalignment is an unlikely possibility.

verification by administrative means is For a primary containment purge valve with a resilient seal acceptable, since access that is isolated in accordance with Required Action D.1, SR 3.6.1.3.5 must be performed at least once every 92 days to these areas is typically following isolation. This provides assurance that restricted. Note 2 degradation of the resilient seal is detected and confirms applies to isolation that the leakage rate of the primary containment purge valve does not increase during the time the penetration is devices that are locked, isolated. The normal Frequency for SR 3.6.1.3.5 is as sealed, or otherwise required by the Primary Containment Leakage Rate Testing secured in position and Program. Since more reliance is placed on a single valve while in this Condition, it is prudent to perform the SR allows these devices to more often. Therefore, a Frequency of once per 92 days was be verified closed by use chosen and has been shown acceptable based on operating experience.

of administrative means.

Allowing verification by administrative means is E.1 and E.2 considered acceptable, If any Required Action and associated Completion Time cannot since the function of be met in MODE 1, 2, or 3, the plant must be brought to a locking, sealing, or MODE in which the LCO does not apply. To achieve this status, the plant must be brought to at least MODE 3 within securing components is 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> and to MODE 4 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed to ensure that these Completion Times are reasonable, based on operating devices are not experience, to reach the required plant conditions from full power conditions in an orderly manner and without inadvertently challenging plant systems.

repositioned.

F.1 If any Required Action and associated Completion Time cannot be met, the plant must be placed in a condition in which the LCO does not apply. If applicable, movement of recently irradiated fuel assemblies (i.e., fuel that has occupied (continued)

CLINTON B 3.6-21 Revision No. 21-7

SCIDs B 3.6.4.2 BASES ACTIONS The third Note ensures appropriate remedial actions are (continued) taken, if necessary, if the affected system(s) are rendered inoperable by an inoperable SCID.

A.1 and A.2 In the event that there are one or more penetration flow paths with one SCID inoperable, the affected penetration flow path(s) must be isolated. The method of isolation must include the use of at least one isolation barrier that cannot be adversely affected by a single active failure.

Isolation barriers that meet this criteria are a closed and de-activated automatic damper, a closed manual damper or valve, or a blind flange. For penetrations isolated in accordance with Required Action A.1, the device used to isolate the penetration should be the closest available device to secondary containment. This Required Action must be completed within the 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time. The specified time period is reasonable considering the time required to isolate the penetration and the low probability of a DBA, which requires the SCIDs to close, occurring during this short time.

For affected penetrations that have been isolated in accordance with Required Action A.1, the affected penetration must be verified to be isolated on a periodic basis. This is necessary to ensure that secondary containment penetrations required to be isolated following an accident, but no longer capable of being automatically isolated, will be isolated should an event occur. This Required Action does not require any testing or isolation device manipulation. Rather, it involves verification that the affected penetration remains isolated. two Notes. Note 1 Required Action A.2 is modified by a Note that applies to isolation devices located in high radiation areas and allows them to be verified by use of administrative controls.

Allowing verification by administrative controls is considered acceptable, since access to these areas is typically restricted. Therefore, the probability of misalignment, once they have been verified to be in the proper position, is low.

(continued)

Note 2 applies to isolation devices that are locked, sealed, or otherwise secured in position and allows these devices to be verified closed by use of administrative means. Allowing verification by administrative means is considered acceptable, since the function of locking, sealing, or securing components is to ensure that these devices are not inadvertently repositioned.

CLINTON B 3.6-91 Revision No. 20-2

No changes to this page. Drywell Isolation Valves B 3.6.5.3 BASES (continued)

ACTIONS The ACTIONS are modified by three Notes. The first Note allows penetration flow paths, except for the drywell vent and purge supply and exhaust penetration flow paths, to be unisolated intermittently under administrative controls.

Due to the size of the drywell vent and purge line penetrations and the fact that they communicate directly with the containment atmosphere, bypassing the suppression pool, these flow paths are not allowed to be unisolated under administrative controls. These controls consist of stationing a dedicated individual, who is in continuous communication with the control room, at the controls of the valve. In this way, the penetration can be rapidly isolated when a need for drywell isolation is indicated.

The second Note provides clarification that for the purpose of this LCO separate Condition entry is allowed for each penetration flow path. This is acceptable, since the Required Actions for each Condition provide appropriate compensatory actions for each inoperable drywell isolation valve. Complying with the Required Actions may allow for continued operation, and subsequent inoperable drywell isolation valves are governed by subsequent Condition entry and application of associated Required Actions.

The third Note requires the OPERABILITY of affected systems to be evaluated when a drywell isolation valve is inoperable. This ensures appropriate remedial actions are taken, if necessary, if the affected system(s) are rendered inoperable by an inoperable drywell isolation valve.

A.1 and A.2 With one or more penetration flow paths with one required drywell isolation valve inoperable, the affected penetration flow path must be isolated. The method of isolation must include the use of at least one isolation barrier that cannot be adversely affected by a single active failure.

Isolation barriers that meet this criterion are a closed and de-activated automatic valve, a closed manual valve, a blind flange, and a check valve with flow through the valve secured. In this condition, the remaining OPERABLE drywell isolation valve is adequate to perform the isolation function for drywell vent and purge system penetrations.

(continued)

CLINTON B 3.6-117 Revision No. 20-2

Drywell Isolation Valves B 3.6.5.3 BASES ACTIONS A.1 and A.2 (continued)

The associated system piping is adequate to perform the isolation function for other drywell penetrations. However, the overall reliability is reduced because a single failure could result in a loss of drywell isolation. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time is acceptable, due to the low probability of the inoperable valve resulting in excessive drywell leakage and the low probability of the limiting event for drywell leakage occurring during this short time. In addition, the Completion Time is reasonable, considering the time required to isolate the penetration and the relative importance of supporting drywell OPERABILITY during MODES 1, 2, and 3.

Alternatively, a Completion Time can be determined in accordance with the Risk Informed Completion Time Program.

For affected penetration flow paths that have been isolated in accordance with Required Action A.1, the affected penetrations must be verified to be isolated on a periodic basis. This is necessary to ensure that drywell penetrations that are required to be isolated following an accident, and are no longer capable of being automatically isolated, will be isolated should an event occur. This Required Action does not require any testing or valve manipulation; rather, it involves verification that those devices outside drywell and capable of potentially being mispositioned are in the correct position. Since these devices are inside primary containment, the time period specified as prior to entering MODE 2 or 3 from MODE 4, if not performed within the previous 92 days, is based on engineering judgment and is considered reasonable in view of the inaccessibility of the devices and other administrative controls that will ensure that misalignment is an unlikely possibility. Also, this Completion Time is consistent with the Completion Time specified for PCIVs in LCO 3.6.1.3, Primary Containment Isolation Valves (PCIVs).

two Notes. Note 1 Required Action A.2 is modified by a Note that applies to isolation devices located in high radiation areas and allows them to be verified by use of administrative controls.

Allowing verification by administrative controls is considered acceptable, since access to these areas is typically restricted. Therefore, the probability of misalignment, once they have been verified to be in the proper position, is low.

(continued)

Note 2 applies to isolation devices that are locked, sealed, or otherwise secured in position and allows these devices to be verified closed by use of administrative means. Allowing verification by administrative means is considered acceptable, since the function of locking, sealing, or securing components is to ensure that these devices are not inadvertently repositioned.

CLINTON B 3.6-118 Revision No. 21-7