NL-24-0126, – Units 3 and 4, License Amendment Request: Changes to Technical Specification 3.7.6, Main Control Room Emergency Habitability System (Ves) Action a and SR 3.7.6.6

– Units 3 and 4, License Amendment Request: Changes to Technical Specification 3.7.6, Main Control Room Emergency Habitability System (Ves) Action a and SR 3.7.6.6

ML24207A252
Person / Time
Site:	Vogtle
Issue date:	07/25/2024
From:	Coleman J Southern Nuclear Operating Co
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
NL-24-0126
Download: ML24207A252 (1)

Text

Regulatory Affairs 3535 Colonnade Parkway Birmingham, AL 35243 205 992 5000

July 25, 2024

Docket Nos.: 52-025 NL-24-0126 52-026 10 CFR 50.90

U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001

Southern Nuclear Operating Company Vogtle Electric Generating Plant - Units 3 and 4 License Amendment Request: Changes to Technical Specification 3.7.6, Main Control Room Emergency Habitability System (VES) Action A and SR 3.7.6.6

Pursuant to 10 CFR 52.98(c) and in accordance with 10 CFR 50.90, Southern Nuclear Operating Company (SNC) requests an amendment to the Combined License (COL) for Vogtle Electric Generating Plant (VEGP) Units 3 and 4 (License Numbers NPF-91 and NPF-92, respectively). The license amendment request (LAR) proposes to revise the COL Appendix A, Technical Specifications (TS), 3.7.6, Main C ontrol Room Emergency Habi tability System (VES)

Action A and Surveillance Requirement (SR) 3.7.6.6 related to inoperable valves and/or dampers.

These changes were previously discussed with the NRC Staff on a public presubmittal conference call on April 16, 2024 [ADAMS Accession No. ML24108A089]. SNC has incorporated information into the request to address topics discussed during the above call.

The Enclosure to this letter provides the description, technical evaluation, regulatory evaluation (including the Significant Hazards Consideration Determination), and environmental considerations for the proposed changes.

This letter contains no regulatory commitments. This letter has been reviewed and determined not to contain security-related information.

SNC requests NRC staff review and approval of this LAR no later than twelve months from acceptance. SNC expects to implement the proposed amendment within 90 days of approval of the LAR.

In accordance with 10 CFR 50.91, SNC is notifying the State of Georgia by transmitting a copy of this letter and its enclosure to the designated State Official.

If you have any questions, please contact Ryan Joyce at (205) 992-6468.

U. S. Nuclear Regulatory Commission NL-24-0126 Page 2

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 25 th of July 2024.

Respectfully submitted,

Jamie M. Coleman Director, Regulatory Affairs Southern Nuclear Operating Company

Enclosure:

Evaluation of Proposed Changes

cc: NRC Regional Administrator, Region ll NRR Project Manager - Vogtle 3 & 4 Senior Resident Inspector - Vogtle 3 & 4 Director, Environmental Protection Division - State of Georgia Document Services RTYPE: VND.LI.L00

Enclosure to NL-24-0126 Evaluation of Proposed Changes

Enclosure to NL-24-0126

Evaluation of Proposed Changes

1.

SUMMARY

DESCRIPTION

2. DETAILED DESCRIPTION 2.1 System Design and Operation 2.2 Current Requirements 2.3 Reason for Proposed Change 2.4 Description of Proposed Change

3. TECHNICAL EVALUATION 3.1 TS 3.7.6 Action A 3.2 SR 3.7.6.6

4. REGULATORY EVALUATION 4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 Significant Hazards Consideration 4.4 Conclusions

5. ENVIRONMENTAL CONSIDERATION

6. REFERENCES

Attachments:

1. Technical Specification Marked-up Pages

2. Revised Technical Specification Pages

3. Technical Specification Bases Marked-up Pages (for information only)

Enclosure to NL-24-0126 Evaluation of Proposed Changes

1.

SUMMARY

DESCRIPTION

The proposed change would revise the Combined License (COLs) for Vogtle Electric Generating Plant (VEGP) Units 3 and 4 by revising COL Appendix A Technical Specification (TS) 3.7.6, Main Control Room Emergency Habitability System (VES)

Action A and Surveillance Requirement (SR) 3.7.6.6 related to inoperable valves and/or dampers. The requested TS changes are as follows:

TS 3.7.6 Action A

Proposed changes to TS 3.7.6 Condition A would identify the condition as One or more valves inoperable with VES safety function maintained OR One or more dampers inoperable with VES safety function maintained, with a Note stating Separate Condition entry is allowed for each valve and each damper.

TS Surveillance Requirement (SR) 3.7.6.6

Proposed changes to SR 3.7.6.6 would editorially revise Verify all to Verify each and to add:, except for valves that are locked, sealed, or otherwise secured in the closed position.

2. DETAILED DESCRIPTION

2.1 System Design and Operation

The nuclear island nonradioactive ventilation system (VBS) normally serves the main control room (MCR). The VBS safe ty-related design basis functions include monitoring the MCR supply air for radioactive particulate and iodine concentrations to isolate the penetrations in the MCR boundary on a VES actuation signal.

The VES provides a protected environment from which operators can control the plant following an uncontrolled release of radioactivity, hazardous chemicals, or smoke. The system is designed to operate following a Design Basis Accident (DBA) that requires protection from the release of radioactivity. In these events, VBS would continue to function if AC power is available. VES is actuated and the MCR pressure boundary isolated on either a High-2 particulate or iodine signal in the VBS supply ducting, a sustained loss of control room differential pressure, a sustained loss of all AC power, or manually by the operators. Concurrent with this action, the main control room envelope (MCRE) pressure relief isolation valves are opened after a short time delay to preclude over-pressurization of the MCRE pressure boundary. In addition the sanitary drainage system (SDS) isolates the SDS vent line penetration in the MCR boundary provide isolation from the surrounding areas and outside environment.

The major functions of the VES are to: 1) provide forced ventilation to deliver an adequate supply of breathable air for the MCR occupants; 2) provide forced ventilation to maintain the MCR at a positive pressure with respect to the surrounding areas; 3) provide passive filtration to filter potential contaminated air in

E-1 Enclosure to NL-24-0126 Evaluation of Proposed Changes

the MCR; and 4) maintain MCR temperature within acceptable limits to assure the MCR equipment and facilities that remain functional during design bases events.

The VES consists of 32 compressed air storage tanks arranged in four banks of eight tanks each, two air delivery flow paths, an eductor, a high efficiency particulate air (HEPA) filter, an activated charcoal adsorber section for removal of gaseous activity (principally iodines), associated valves or dampers, piping, and instrumentation.

The VES consists of compressed air storage tanks, and air delivery flow paths consisting of two main (with two parallel automatically actuated flow paths) and an alternate (a manually actuated flow path) air delivery flow path. During operation of the VES, a self-contained pressure regulating air delivery valve (one common to the main air delivery flow paths and one in the alternate air delivery flow path) maintains a constant downstream pressure regardless of the upstream pressure.

Either the eductor, which contains a fixed single plate orifice, or the orifice in the secondary VES bypass line, is used to control the air flow rate into the MCR. The VES is designed to maintain the MCR at 1/8-inch water gauge positive pressure relative to surrounding areas to minimize the infiltration of airborne contaminants from the surrounding areas. The VES operation in maintaining the MCR habitable is discussed in Updated Final Safety Analysis Report (UFSAR) Section 6.4.

2.2 Current Requirements

TS 3.7.6 Condition A states: One valve or damper inoperable.

The Surveillance for SR 3.7.6.6 states: Verify all MCRE isolation valves are OPERABLE and will close upon receipt of an actual or simulated actuation signal.

2.3 Reason for Proposed Change

TS 3.7.6 Action A

Condition A allows only one valve or damper to be inoperable at any one time; otherwise, Condition F and/or Condition G is required to be entered, which leads to a prompt plant shutdown. This represents an excessively restrictive and unnecessarily potential for an unplanned plant shutdown when the VES safety function might still be maintained. While there have been minimal entries into TS 3.7.6 Action A for inoperable valves or dampers, the potential exits.

SR 3.7.6.6

The proposed change is consistent with similar changes approved by TSTF-541, Add Exceptions to Surveillance Requirements for Valves and Dampers Locked in the Actuated Position. The NRC Staff approved the TSTF to provide explicit exceptions in the text of selected SRs to avoid unnecessarily declaring the LCO not met when a valve or damper is not capable of meeting the SR but, within the confines of the exception, the system, subsystem, or train/division to which it belongs is still capable of performing its specified safety function. This is the case

E-2 Enclosure to NL-24-0126 Evaluation of Proposed Changes

of the VEGP TS SR 3.7.6.6 for isolation valves that can be locked, sealed, or otherwise secured in the closed position. This proposed change will provide greater consistency with other Standard Technical Specifications, and provide improved flexibility consistent with maintaining safe plant operations.

2.4 Description of Proposed Change

TS 3.7.6 Action A

Revise Condition A to state (underlines highlight addition): One or more valves or damper inoperable with VES safety function maintained OR One or more dampers inoperable with VES safety function maintained with an added Note stating:

Separate Condition entry is allowed for each valve and each damper.

SR 3.7.6.6

Revise the Surveillance to state (underlines highlight addition) : Verify all each MCRE isolation valves are is OPERABLE and will close upon receipt of an actual or simulated actuation signal, except for valves that are locked, sealed, or otherwise secured in the closed position.

Markups showing the TS changes are provided in Attachment 1.

3. TECHNICAL EVALUATION

3.1 TS 3.7.6 Action A

Currently, TS 3.7.6 Action A allows only a single valve or damper to be inoperable.

However, the VES design consists of various functions to support the VES safety function to maintain the MCR environment suitable for prolonged occupancy throughout the duration of the postulated accidents that require protection from the release of radioactivity, including maintaining CO 2 concentration to less than 0.5 percent for up to 11 main control room occupants. Each function has designed redundancy for single failure protection such that multiple valves and/or dampers may be concurrently inoperable while still retaining the VES safety function.

VBS and SDS Isolation

The VBS supply flow path isolation valves (VBS-V186 and -V187) and return flow path isolation valves (VBS-V188 and -V 189), toilet exhaust flow path isolation valves (VBS-V190 and -V191), as well as the sanitary vent line flow path isolation valves (SDS-V001 and -V002) provides for redundant isolation capability in each flow path to isolate penetrations in the MCR boundary. Each flow path is provided with redundant isolation valves to ensure that at least one means of isolation is available assuming a single failure to maintain the flow path isolation safety function.

E-3 Enclosure to NL-24-0126 Evaluation of Proposed Changes

VES Air Delivery

The air delivery flow paths consist of a main air delivery flow path with a self-contained two-stage pressure regulating air delivery valve (VES-V002A) and two 100% parallel automatically actuated flow paths (VES-V005A/B). Additionally, there is a separate 100% alternate air delivery flow path via a manually actuated valve (VES-V001) with a two-stage pressure regulating air delivery valve (VES-V002B). A failure of either stage of the pressure regulating valve will not cause the valve to fail completely open. A failure of the second stage of the pressure-regulating valve will increase flow from the emergency air storage tanks; however, there is adequate margin in the emergency air storage tanks such that an operator has time to isolate the line and manually actuate the alternative delivery line. The three air delivery flow paths (VES-V002A with VES-V005A, VES-V002A with VES-V005B, and VES-V002B with VES-V001) comprise the air delivery function. The design provides that at least one flow path is available assuming a single failure to maintain the air delivery safety function.

VES Distribution Flow

The VES MCR air filtration line balancing dampers (VES-D002 and -D003) provide flow distribution in the ducting for delivery of recirculated air throughout the MCR boundary. The dampers split flow between the Main Control Area and the Shift Managers Office. The air delivery ducting and dampers comprise the distribution function. Single failure analysis demonstrates acceptable VES performance in the event one of these dampers fails. The design provides single failure protection to maintain the distribution flow safety function.

VES Pressure Relief

The VES pressure relief isolation valves and pressure relief dampers open to ensure that adequate vent area is available to mitigate MCRE overpressurization.

The two redundant pressure relief flow paths (VES-V022A with VES-D001A and VES-V022B with VES-D001B) comprise the pressure relief function. The design provides single failure protection to maintain the pressure relief safety function.

Additionally, each pressure relief flow path is also required to be closed when not relieving pressure to maintain the MCRE boundary. Each flow path is provided with redundant isolation devices to ensure that at least one is available assuming a single failure to maintain the pressure relief flow path isolation safety function.

VES Eductor Bypass

The VES eductor bypass isolation valve (VES-V046) can be manually opened to ensure continued delivery of breathable air in the event a passive failure disables the passive filtration flow path (e.g., a filtration train blockage) after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> as assumed in the safety analysis assumptions for modeling the doses to the main control room personnel. Manually opening the eductor bypass flow path after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> provides single failure protection to maintain the necessary VES breathable air safety function. The safety function is maintained either by the normally aligned passive filtration flow path or the manually actuated VES eductor bypass.

E-4 Enclosure to NL-24-0126 Evaluation of Proposed Changes

Addition of Separate Condition Entry Note

The proposed change to add a Note stating Separate Condition entry is allowed for each valve and each damper is a typical provision found throughout the TS for cases where there are independent flow paths or functions that can individually retain the associated safety function (i.e., where the Condition results in only loss of single failure protection). This is the intent of the Required Action A.1 Completion Time as expressed in the current TS Bases, which states (in part):

The Completion Time of 7 days is based on engineering judgment, considering...

that the remaining components can provide the required capability. Therefore, the 7day Completion Time applied separately for each inoperable valve or damper when the VES safety function is maintained continues to provide the appropriate restoration action and Completion Time for each inoperable valve or damper.

TS Section 1.3, Example 1.3-5, discusses this Note (and placement in the Condition) providing the appropriate use and application for the proposed Note.

This example also shows the use of or more with plural valves or dampers and continued use of singular in the Required Action. Separating the condition for inoperable valves and inoperable dampers with a logical connector (i.e., OR) is appropriate convention as also seen in VEGP Unis 3 &4 TS 3.1.9, Chemical and Volume Control System (CVS) Demineralized Water Isolation Valves and Makeup Line Isolation Valves, Condition A.

It is also noted that NUREG-1431, Westinghouse Standard Technical Specifications (ADAMS Accession No. ML21259A155) provides a similar example for Actions supporting an evaluation of retaining the safety function in order to support utilizing an appropriate restoration time. In NUREG-1431, LCO 3.5.2, ECCS - Operating, Condition A allows any number of inoperable ECCS components, provided Condition C does not apply, which is an evaluation that the safety function (i.e., 100% of the ECCS flow equivalent to a single Operable ECCS train is available).

3.2 SR 3.7.6.6

Consistent with TSTF-541, the proposed exception permits MCRE isolation valves to be exempted from testing under the SR. The allowance and the proposed change do not involve a plant design change. If a valve is locked, sealed, or otherwise secured to support plant operation, restoration to the design condition is controlled by plant procedures, changes to which are also governed by 10 CFR 50.59. If the valve is locked, sealed, or otherwise secured to facilitate maintenance, restoration is governed by 10 CFR 50, Appendix B, Criterion XVI, and 10 CFR 50.65. If the SR exception is utilized and the specified Frequency of the SR is exceeded without testing the component, the SR must be performed on the component when it is returned to service in order to meet the SR.

The proposed change does not permit a system that is inoperable to be considered operable. As stated in the SR 3.0.1 Bases, Nothing in this Specification, however, is to be construed as implying that systems or components

E-5 Enclosure to NL-24-0126 Evaluation of Proposed Changes

are OPERABLE when The systems or components are known to be inoperable, although still meeting the SRs.

Placing a MCRE isolation valve in a condition not consistent with the design (i.e.,

locked, sealed, or otherwise secured in the closed position ) requires consideration of the effect on the operab ility of VES or any supported systems. As described in the proposed TS Bases changes, SNC administrative processes require assessing VES operability or any supported systems when utilizing this SR allowance. The operability assessment will consider whether there is an assumption in the safety analysis that requires movement of the affected valves or dampers following an event. SNC acknowledges that under the proposed change, the affected valve(s) may be excluded from the SR when locked, sealed or otherwise secured in the actuated position. However, if the safety analysis assumes movement from the actuated position following an event, or the system is rendered inoperable by locking, sealing, or otherwise securing the valve or damper in the actuated position, then the system cannot perform its specified safety function and is inoperable regardless of whether the SR is met.

As stated in the proposed TS Bases, the automatic valve is verified to be in the correct position prior to locking, sealing, or securing it in position. While in the actuated position, verification of automatic actuation or valve isolation time is not necessary as the specified safety function is assured. However, as with the existing similar SR allowances, the SR must be verified to be met within its required Frequency after removing the valve from the locked, sealed or otherwise secured status. SNC acknowledges for valve(s) where the SR allowance is utilized, the SR will be verified to have been met within its required Frequency after removing the valve from the locked, sealed or otherwise secured status. If the SR exception is utilized and the specified Frequency of the SR is exceeded without testing the component, the SR will be performed on the component when it is returned to service in order to meet the SR prior to declaring the valve operable.

An additional editorial change is proposed to revise Verify all MCRE isolation valves are to Verify each MCR isolation valve is for consistency, as this is the only occurrence of Verify all currently in the VEGP TS while Verify each is otherwise consistently used throughout. Since the meaning is unchanged, this is considered an administrative presentation preference only.

In conclusion, the proposed changes provide additional clarification consistent with the intent of providing a reasonable restoration time while the VES safety function is maintained. These changes continue to provide the appropriate assurance of the required of protection for the MCR plant operations staff in meeting General Design Criterion 19. Therefore, there is reasonable assurance that the health and safety of the public, and the MCR staff, will not be endangered by operation in the proposed manner.

E-6 Enclosure to NL-24-0126 Evaluation of Proposed Changes

4 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements/Criteria

In conformance with 10 CFR 50.36(c)(2) the VEGP Units 3 and 4 Combined License (COL) Appendix A Technical Specif ications (TS) provides a Limiting Condition for Operation (LCO) for the Main Control Room Emergency Habitability System (VES) as TS 3.7.6. Also, in conformance with 10 CFR 50.36(c)(2), when that LCO is not met the TS provide for associated remedial actions until the condition can be met as permitted in the TS 3.7.6 Actions. Thus, the proposed changes are consistent with the requirements of 10 CFR 50.36

In conformance with 10 CFR 50.36(c)(3) su rveillance requirements in conformance with 10 CFR 50.36, relating to test, calibration, and inspection to assure that the necessary quality of systems and components is maintained, facility operation will be within safety limits, and the limiting conditions for operation will be met. The proposed revision to the surveillance requirements is appropriate to continue to fulfill this regulation. Thus, the proposed changes are consistent with the requirements of 10 CFR 50.36.

10 CFR Part 50, Appendix A, General Design Criteria (GDC) 19 requires that adequate radiation protection be provided to permit access and occupancy of the control room under accident conditions without personnel receiving radiation exposures in excess of 5 rem whole body, or its equivalent to any part of the body, for the duration of the accident. The proposed revisions are appropriate to continue to fulfill this regulation. Thus, the proposed change is consistent with the requirements of 10 CFR Part 50, Appendix A, GDC 19.

4.2 Precedent

Letter John G. Lamb (NRC) to Cheryl A. Gayheart (SNC), July 31, 2021, Farley 1

& 2, Hatch 1 & 2, Vogtle 1 & 2-Issuance of Amendments Regarding Revision to Technical Specifications to Adopt TSTF-541, Rev.2, Add Exceptions to Surveillance Requirements for Valves & Dampers Locked in Actuated Position "

[ADAMS Accession No. ML21167A315].

4.3 Significant Hazards Consideration

Southern Nuclear Operating Company (SNC) is requesting an amendment to Combined License (COL) Nos. NPF-91 and NPF-92 for Vogtle Electric Generating Plant (VEGP) Units 3 and 4, respectively. The license amendment request (LAR) proposes to revise the Combined License (COL) Appendix A, Technical Specifications (TS), 3.7.6, Main Cont rol Room Emergency Habitability System (VES) Action A and Surveillance Requirement (SR) 3.7.6.6 related to inoperable valves and/or dampers.

An evaluation to determine whether or not a significant hazards consideration is involved with the proposed amendment was completed by focusing on the three standards set forth in 10 CFR 50.92(c), Issuance of amendment, as discussed below.

E-7 Enclosure to NL-24-0126 Evaluation of Proposed Changes

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

Response: No

The proposed changes do not affect the previously evaluated accident probability because there are no changes to the plant. The proposed changes do not adversely affect the operation of any structures, systems, or components (SSCs) associated with an accident initiator or initiating sequence of events. The proposed changes continue to maintain the initial conditions, operating limits, and safety function assumed during normal operation and in the analysis of accidents and anticipated operational occurrences. Therefore, the proposed changes do not result in any increase in probability of an analyzed accident occurring.

The proposed changes do not involve a change to any mitigation sequence or the predicted radiological releases due to postulated accident conditions. The proposed changes do not significantly affect previously evaluated accident consequences since the proposed standard for air quality continues to provide breathing air appropriate for main control room personnel. Thus, the consequences of the accidents previously evaluated are not adversely affected.

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 changes continue to provide the required functional capability of the safety systems for previously evaluated accidents and anticipated operational occurrences. The proposed changes do not adversely impact the function of any related systems, and thus, the changes do not introduce a new failure mode, malfunction, or sequence of events that could adversely affect safety or safety-related equipment.

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

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

Response: No.

The proposed changes continue to provide the required functional capability of the safety systems for previously evaluated accidents and anticipated operational occurrences while operating within the allowed Completion Time

E-8 Enclosure to NL-24-0126 Evaluation of Proposed Changes

for conditions where single failure protection is not provided, but safety function is maintained. The proposed changes do not change the function of the related systems nor significantly affect the margins provided by the systems.

The proposed change does not adversely impact the air flowrate supplied to the MCR to support respiration of the MCR occupants. No safety analysis or design basis acceptance limit/criterion is challenged or exceeded by the requested changes.

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

Based on the above, it is concluded that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of no significant hazards consideration is justified.

4.4 Conclusions

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 Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public. Therefore, it is concluded that the requested amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of no significant hazards consideration is justified.

5 ENVIRONMENTAL CONSIDERATION

The proposed changes to the Technical Specifications (TS) are described in Section 2 of this Enclosure, which require a license amendment. SNC has evaluated this license amendment request against the criter ia for identification of licensing and regulatory actions requiring environmental assessment in accordance with 10 CFR 51.21.

The requested amendment would change a surveillance requirement; however, meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9), in that the amendment would not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.

Accordingly, the proposed amendment meets t he eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or envir onmental assessment need be prepared in connection with the proposed amendment.

E-9 Enclosure to NL-24-0126 Evaluation of Proposed Changes

6 REFERENCES

None.

E-10 Technical Specification Marked-up Pages

Attachment 1

Technical Specification Marked-up Pages

Insertions Denoted by underlined Blue text and Deletions by Red Strikethrough Omitted text is identified by three asterisks ( * * * )

(This Attachment consists of 3 pages, including this cover page)

Technical Specifications VES 3.7.6

3.7 PLANT SYSTEMS

3.7.6 Main Control Room Emer gency Habitability System (VES)

LCO 3.7.6 The VES shall be OPERABLE.

- NOTE -

The main control room envelope (MCRE) boundary may be opened intermittently under administrative control.

APPLICABILITY: MODES 1, 2, 3, and 4, During movement of irradiated fuel assemblies.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME

A. -------------------------------- A.1 Restore valve or damper to 7 days

- NOTE - OPERABLE status.

Separate Condition entry is allowed for each valve and each damper.

One or more valves or damper inoperable with VES safety function maintained.

OR

One or more dampers inoperable with VES safety function maintained.

B. One PMS Division B.1 Restore PMS division in 7 days inoperable in one or both MCR load shed more MCR load shed panels to OPERABLE panel(s). status.

VEGP Units 3 and 4 3.7.6 - 1 Amendment No.___108 (Unit 3)

Amendment No.___107 (Unit 4)

Technical Specifications VES 3.7.6

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY

SR 3.7.6.1 Verify the compressed air storage tanks contain 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />

> 327,574 scf of compressed air.

SR 3.7.6.2 Verify thermal mass for the following heat sink 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> locations is within limit:

a. MCRE;

b. Each required individual room adjacent to and below MCRE;

c. Each required room-pair adjacent to and below MCRE; and

d. Room above MCRE.

SR 3.7.6.3 Operate VES for 15 minutes. 31 days on a STAGGERED TEST BASIS

SR 3.7.6.4 Verify each VES air header manual isolation valve is 31 days in an open position.

SR 3.7.6.5 Verify the air quality of the air storage tanks meets the 92 days requirements of Appendix C, Table C-1 of ASHRAE Standard 62 with a pressure dew point of 40°F at 3400 psig.

SR 3.7.6.6 Verify eachall MCRE isolation valves isare 24 months OPERABLE and will close upon receipt of an actual or simulated actuation signal, except for valves that are locked, sealed, or otherwise secured in the closed position.

SR 3.7.6.7 Verify each VES pressure relief isolation valve within In accordance with the MCRE pressure boundary is OPERABLE. the Inservice Testing Program

SR 3.7.6.8 Verify each VES pressure relief damper is 24 months OPERABLE.

VEGP Units 3 and 4 3.7.6 - 4 Amendment No.___183 (Unit 3)

Amendment No.___181 (Unit 4)

Revised Technical Specification Pages

Attachment 2

Revised Technical Specification Pages

(This Attachment consists of 3 pages, including this cover page)

Technical Specifications VES 3.7.6

3.7 PLANT SYSTEMS

3.7.6 Main Control Room Emer gency Habitability System (VES)

LCO 3.7.6 The VES shall be OPERABLE.

- NOTE -

The main control room envelope (MCRE) boundary may be opened intermittently under administrative control.

APPLICABILITY: MODES 1, 2, 3, and 4, During movement of irradiated fuel assemblies.

ACTIONS CONDITION REQUIRED ACTION COMPLETION TIME

A. -------------------------------- A.1 Restore valve or damper to 7 days

- NOTE - OPERABLE status.

Separate Condition entry is allowed for each valve and each damper.

One or more valves inoperable with VES safety function maintained.

OR

One or more dampers inoperable with VES safety function maintained.

B. One PMS Division B.1 Restore PMS division in 7 days inoperable in one or both MCR load shed more MCR load shed panels to OPERABLE panel(s). status.

VEGP Units 3 and 4 3.7.6 - 1 Amendment No. ___ (Unit 3)

Amendment No. ___ (Unit 4)

Technical Specifications VES 3.7.6

ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME

C. Thermal mass of one or C.1 Restore required heat sink 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> more required heat air temperatures to within sink(s) not within limit(s). limit(s).

AND

C.2 Restore thermal mass of 5 days required heat sink(s) to within limit(s).

D. VES inoperable due to D.1 Initiate action to implement Immediately inoperable MCRE mitigating actions.

boundary in MODE 1, 2, 3, or 4. AND

D.2 Verify mitigating actions 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> ensure MCRE occupant exposures to radiological, chemical, and smoke hazards will not exceed limits.

AND

D.3 Restore MCRE boundary 90 days to OPERABLE status.

E. One bank of VES air E.1 Verify that the OPERABLE 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> tanks inoperable. tanks contain

> 245,680 scf of AND compressed air.

Once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> thereafter

AND

E.2 Verify VBS MCRE ancillary 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> fans and supporting equipment are available.

AND

E.3 Restore VES to 7 days OPERABLE status.

VEGP Units 3 and 4 3.7.6 - 2 Amendment No. ___ (Unit 3)

Amendment No. ___ (Unit 4)

Technical Specifications VES 3.7.6

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY

SR 3.7.6.1 Verify the compressed air storage tanks contain 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />

> 327,574 scf of compressed air.

SR 3.7.6.2 Verify thermal mass for the following heat sink 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> locations is within limit:

a. MCRE;

b. Each required individual room adjacent to and below MCRE;

c. Each required room-pair adjacent to and below MCRE; and

d. Room above MCRE.

SR 3.7.6.3 Operate VES for 15 minutes. 31 days on a STAGGERED TEST BASIS

SR 3.7.6.4 Verify each VES air header manual isolation valve is 31 days in an open position.

SR 3.7.6.5 Verify the air quality of the air storage tanks meets the 92 days requirements of Appendix C, Table C-1 of ASHRAE Standard 62 with a pressure dew point of 40°F at 3400 psig.

SR 3.7.6.6 Verify each MCRE isolation valve is OPERABLE and 24 months will close upon receipt of an actual or simulated actuation signal, except for valves that are locked, sealed, or otherwise secured in the closed position.

SR 3.7.6.7 Verify each VES pressure relief isolation valve within In accordance with the MCRE pressure boundary is OPERABLE. the Inservice Testing Program

SR 3.7.6.8 Verify each VES pressure relief damper is 24 months OPERABLE.

VEGP Units 3 and 4 3.7.6 - 4 Amendment No. ___ (Unit 3)

Amendment No. ___ (Unit 4)

Technical Specification Bases Marked-up Pages (For Information Only)

Attachment 3

Technical Specification Bases Marked-up Pages (For Information Only)

Insertions Denoted by underlined Blue text and Deletions by Red Strikethrough Omitted text is identified by three asterisks ( * * * )

(This Attachment consists of 7 pages, including this cover page)

Technical Specifications Bases VES B 3.7.6

B 3.7 PLANT SYSTEMS

B 3.7.6 Main Control Room Emergency Habitability System (VES)

BASES

BACKGROUND The Main Control Room Emergency Habitability System (VES) provides a protected environment from which operators can control the plant following an uncontrolled release of radioactivity, hazardous chemicals, or smoke. The system is designed to operate following a Design Basis Accident (DBA) which requires protection from the release of radioactivity.

In these events, the Nuclear Island Non-Radioactive Ventilation System (VBS) would continue to function if AC power is available. If AC power is lost for greater than 10 minutes, or Low main control room differential pressure is sensed for greater than 10 minutes, or a High-2 iodine or particulate Main Control Room Envelope (MCRE) radiation signal is received, the VES is actuated. The MCRE radioactivity is measured by detectors in the Main Control Room (MCR) supply air duct, downstream of the filtration units. The major functions of the VES are: 1) to provide forced ventilation to deliver an adequate supply of breathable air (Ref. 4) for the MCRE occupants; 2) to provide forced ventilation to maintain the MCRE at a 1/8 inch water gauge positive pressure with respect to the surrounding areas; 3) provide passive filtration to filter contaminated air in the MCRE; and 4) to limit the temperature increase of the MCRE equipment and facilities that must remain functional during an accident, via de-energizing (load shedding) nonessential, non-safety main control room (MCR) electrical equipment (e.g., wall panel information system displays, office equipment, water heater, kitchen appliances, and non-emergency lighting) and the heat absorption of passive heat sinks.

The VES consists of compressed air storage tanks, two main (with two parallel automatically actuated flow paths) and an alternate (a manually actuated flow path) air delivery flow paths, an eductor, a high efficiency particulate air (HEPA) filter, an activated charcoal adsorber section for removal of gaseous activity (principally iodines), associated valves or dampers, piping, and instrumentation. The tanks contain enough breathable air to supply the required air flow to the MCRE for at least 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The VES system is designed to maintain CO 2 concentration less than 0.5% for up to 11 MCRE occupants.

There are 32 compressed air storage tanks arranged in 4 banks. Each bank nominally provides at least 81,893.5 scf of compressed air to support the minimum required 327,574 scf. With the compressed air equivalent of one bank of tanks unavailable, verifying > 245,680 scf of compressed air ensures the equivalent of three banks remains available to supply air to the MCRE for 54 hours6.25e-4 days <br />0.015 hours <br />8.928571e-5 weeks <br />2.0547e-5 months <br /> (75% of the required 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />).

The VBS supplemental filtration mode or MCRE ancillary fans are both capable of maintaining the habitability of the MCRE after 54 hours6.25e-4 days <br />0.015 hours <br />8.928571e-5 weeks <br />2.0547e-5 months <br />.

VEGP Units 3 and 4 B 3.7.6 - 1 Revision __ 72 Technical Specifications Bases VES B 3.7.6

BASES

APPLICABLE SAFETY ANALYSES (continued)

automatically isolated. VES air flow is initiated by a safety related signal which opens the isolation valves in the VES supply lines.

The VES provides protection from smoke and hazardous chemicals to the MCRE occupants. The analysis of hazardous chemical releases demonstrates that the toxicity limits are not exceeded in the MCRE following a hazardous chemical release (Ref. 1). The evaluation of a smoke challenge demonstrates that it will not result in the inability of the MCRE occupants to control the reactor either from the control room or from the remote shutdown room (Ref. 2).

The VES functions to mitigate a DBA or transient that either assumes the failure of or challenges the integrity of the fission product barrier.

The VES satisfies the requirements of Criterion 3 of 10 CFR 50.36(c)(2)(ii).

LCO The VES limits the MCRE temperature rise and maintains the MCRE at a positive pressure relative to the surrounding environment.

Tw oThe main air delivery flow path, with two parallel automatically actuated flow paths, and the alternate manually actuated air delivery flow paths are required to be OPERABLE for opening to ensure that at least one is available, assuming a single failure. The three air delivery flow paths (VES-PL-V002A with VES-PL-V005A, VES-PL-V002A with VES-PL-V005B, and VES-PL-V002B with VES-PL-V001) comprise the air delivery function.

The VES pressure relief isolation valves and pressure relief dampers are required to be OPERABLE for opening to ensure that adequate vent area is available to mitigate MCRE overpressurization. The two pressure relief flow paths (VES-PL-V022A with VES-MD-D001A and VES-PL-V022B with VES-MD-D001B) comprise the pressure relief function. Each flow path is also required to be closed when not relieving pressure to maintain the MCRE boundary and is provided with redundant isolation devices to ensure that at least one is available assuming a single failure.

The VES eductor bypass isolation valve (VES-PL-V046) is required to be OPERABLE for opening to ensure continued delivery of breathable air in the event a passive failure (e.g., a blockage) disables the passive filtration flow path after 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> as assumed in the safety analysis assumptions (Ref. 1) for modeling the doses to the main control room personnel. This flow path comprises the eductor bypass function.

VEGP Units 3 and 4 B 3.7.6 - 5 Revision __ 72 Technical Specifications Bases VES B 3.7.6

BASES

LCO (continued)

The VES MCR air filtration line balancing dampers (VES-MD-D002 and -D003) are required to be OPERABLE for opening for flow distribution in the ducting for delivery of recirculated air throughout the MCR boundary. The dampers split flow between the Main Control Area and the Shift Managers Office; however, single failure analysis (Ref. 1) demonstrates acceptable VES performance in the event one of these dampers fails. The air delivery ducting and dampers comprise the distribution function.

The VBS supply flow path isolation valves (VBS-PL-V186 and -V187) and return flow path isolation valves (VBS-PL-V188 and -V189), as well as toilet exhaust flow path isolation valves (VBS-PL-V190 and -V191) are required to be OPERABLE to isolate the MCRE. Each flow path is provided with redundant isolation valves to ensure that at least one is available assuming a single failure.

The MCR SDS vent line isolation valves (SDS-PL-V001 and -V002) are required to be OPERABLE to isolate the MCR envelope from the surrounding areas and outside environment. The vent line flow path is provided with redundant isolation valves to ensure that at least one is available assuming a single failure.

The VES OPERABILITY requires that is considered OPERABLE when the individual components necessary to deliver a supply of breathable air to the MCRE are OPERABLE. Each tank must be aligned and each bank must be aligned to be considered OPERABLE and the combined volume of compressed air of the aligned storage tanks must be > 327,574 scf, which is equivalent to each of four banks providing 81,893.5 scf.

In addition, the MCRE pressure boundary must be maintained, including the integrity of the walls, floors, ceilings, electrical and mechanical penetrations, and access doors. The MCRE pressure boundary includes the Potable Water System (PWS) and SDS running (piping drain) traps, which retain a fluid level sufficient to maintain a seal preventing gas flow through the piping. The MCRE pressure boundary also includes the Waste Water System (WWS) drain line, which is isolated by a normally closed isolation valve.

VEGP Units 3 and 4 B 3.7.6 - 6 Revision __ 72 Technical Specifications Bases VES B 3.7.6

BASES

APPLICABILITY In MODES 1, 2, 3, and 4 and during movement of irradiated fuel assemblies, the VES must be OPERABLE to ensure that the MCRE will remain habitable during and following a DBA.

The VES is not required to be OPERABLE in MODES 5 and 6 when irradiated fuel is not being moved because accidents resulting in fission product release are not postulated.

ACTIONS A.1

When a one or more of the following VES functions have only one inoperable flow path (e.g., one or more inoperable for opening VES valve, a or VES damper, in a flow path of one of the below listed types of functions), the VES safety function is maintained for that type of function:

Air Delivery Function, Pressure Relief Function, Eductor Bypass Function, and Distribution Function.

When one or more of the following VES, SDS vent line, or a main control room boundary isolation valve is inoperable, flow paths have only one valve inoperable for closing, the VES safety function is maintained:

Pressure relief flow path, VBS Isolation flow path, and SDS vent line flow path.

In this condition, action is required to restore the component affected VES valve or damper to OPERABLE status. A Completion Time of 7 days is permitted to restore the valve or damper to OPERABLE status before action must be taken to reduce power. The Completion Time of 7 days is based on engineering judgment, considering the low probability of an accident that would result in a significant radiation release from the fuel, the low probability of not containing the radiation, and that the remaining components can provide the required capabilityVES safety function. In the event the VES safety function is not maintained, entry into Condition F and/or Condition G is required.

VEGP Units 3 and 4 B 3.7.6 - 8 Revision __ 72 Technical Specifications Bases VES B 3.7.6

BASES

ACTIONS (continued)

Condition A is modified by a Note that states separate Condition entry is allowed for each valve and each damper. This is acceptable, since each function and flow path is provided with redundancy such that sufficient remaining OPERABLE valves and dampers can provide appropriate VES safety function during the 7 day Completion Time. Complying with the Required Actions may allow for continued operation during the 7 day Completion Time, and a subsequent inoperable valve or damper is governed by subsequent Condition entry and application of associated Required Action.

B.1

If one division of one or more MCR load shed panel(s) is inoperable, all divisions of both MCR load shed panels must be restored to OPERABLE status within 7 days. In this condition, the OPERABLE unaffected division of the panel is capable of providing 100% of the load shed function.

A Completion Time of 7 days is permitted to restore the inoperable division of MCR load shed panel(s) to OPERABLE status before action must be taken to reduce power. The Completion Time of 7 days is based on engineering judgment, considering the low probability of an accident that would require VES actuation, and that the remaining panel division can provide the required load shed function.

As described in Subsection 6.4.2.3 of Ref. 1, any component failure in a PMS division of the load shed panel(s) renders that division inoperable. If this failure affects only one PMS division, leaving the remaining division of PMS unaffected, including the associated power and control circuit, it renders the panel(s) inoperable, while still maintaining the full load shed function. An event or action that impacts both PMS divisions in either panel does not maintain the full load shed function, and Condition F or G of LCO 3.7.6 would apply.

C.1 and C.2

When the thermal mass of one or more of the required MCRE heat sinks (the MCRE, individual required rooms adjacent to and below the MCRE, required room-pairs adjacent to and below the MCRE, and the room above the MCRE) is not within the required limit(s), the heat sink air temperature must be restored to within limit in 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and the thermal mass of the required heat sink(s) must be restored to within limit(s) in 5 days.

VEGP Units 3 and 4 B 3.7.6 - 9 Revision __ 72 Technical Specifications Bases VES B 3.7.6

BASES

SURVEILLANCE REQUIREMENTS (continued)

SR 3.7.6.5

Verification that the air quality of the air storage tanks meets the requirements of Appendix C, Table C-1 of ASHRAE Standard 62 (Ref. 4) with a pressure dew point of 40°F at 3400 psig is required every 92 days. If air has not been added to the air storage tanks since the previous verification, verification may be accomplished by confirmation of the acceptability of the previous surveillance results along with examination of the documented record of air makeup. The purpose of ASHRAE Standard 62 states: This standard specifies minimum ventilation rates and indoor air quality that will be acceptable to human occupants and are intended to minimize the potential for adverse health effects. Verification of the initial air quality (in combination with the other surveillances) ensures that breathable air is available for 11 MCRE occupants for at least 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Confirmation of the pressure dew point verifies that water has not formed in the line, eliminating the potential for freezing at the pressure regulating valve during VES operation. In addition, the dry air allows the MCRE to remain below the maximum relative humidity to support the 90°F WBGT required for human factors performance.

SR 3.7.6.6

Verification that the VBS isolation valves and the Sanitary Drainage System (SDS) isolation valves are OPERABLE and will actuate upon demand is required every 24 months to ensure that the MCRE can be isolated upon loss of VBS operation. The SR excludes automatic valves that are locked, sealed, or otherwise secured in the actuated position.

The SR does not apply to valves that are locked, sealed, or otherwise secured in the actuated position since the affected valves were verified to be in the actuated position prior to being locked, sealed, or otherwise secured. Placing an automatic valve in a locked, sealed, or otherwise secured position requires an assessment of the operability of the system or any supported systems, including whether it is necessary for the valve to be repositioned to the non-actuated position to support the accident analysis. Restoration of an automatic valve to the non-actuated position requires verification that the SR has been met within its required Frequency. The actual or simulated signal is processed through the component interface module to verify the continuity between the output of the component interface module and the valves.

VEGP Units 3 and 4 B 3.7.6 - 15 Revision __ 72