ML12333A240

Unit I, Application to Modify Technical Specification 3.7.10, Control Room Emergency Ventilation System (WBN-TS-12-01)

ML12333A240
Person / Time
Site:	Watts Bar
Issue date:	11/19/2012
From:	James Shea Tennessee Valley Authority
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
WBN-TS-12-01
Download: ML12333A240 (26)

Text

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 November 19, 2012 10 CFR 50.90 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Watts Bar Nuclear Plant Unit 1 Facility Operating License No. NPF-90 NRC Docket No. 50-390

Subject:

Watts Bar Nuclear Plant (WBN) Unit I - Application to Modify Technical Specification 3.7.10, "Control Room Emergency Ventilation System (CREVS)" (WBN-TS-12-01)

In accordance with the provisions of 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," the Tennessee Valley Authority (TVA) is submitting a request for an amendment to Facility Operating License No. NPF-90 for Watts Bar Nuclear Plant (WBN) Unit 1.

This license amendment request seeks approval to change the WBN Unit 1 Technical Specification (TS) 3.7.10 to require a unit shutdown within the TS 3.7.10 Actions instead of entering Limiting Condition for Operation (LCO) 3.0.3 when both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met.

The enclosure to this letter provides a description, technical evaluation, regulatory evaluation and environmental consideration of the proposed changes. Attachments 1 and 2 of the enclosure provide the existing WBN Unit 1 TS pages and TS Bases pages marked up to show the proposed changes, respectively. Attachments 3 and 4 of the enclosure provide the existing WBN Unit 1 TS pages and TS Bases pages retyped to show the proposed changes, respectively.

TVA requests that the NRC approve this amendment by November 19, 2013, with implementation within 60 days of issuance.

TVA has determined that there are no significant hazards considerations associated with the proposed changes and that the changes-qualify for a categorical exclusion from environmental review pursuant to the provisions of 10 CFRe.51.22(c)(9).

Printed on recycled paper

U.S. Nuclear Regulatory Commission Page 2 November 19, 2012 The WBN Plant Operations Review Committee and the WBN Nuclear Safety Review Board have reviewed the proposed changes and determined that operation of WBN in accordance with the proposed changes will not endanger the health and safety of the public.

Additionally, in accordance with 10 CFR 50.91 (b)(1), TVA is sending a copy of this letter and the enclosure to the Tennessee Department of Environment and Conservation.

This submittal does not contain any new regulatory commitments. Please address any questions regarding this request to Terry Cribbe at 423-751-3850.

I declare under penalty of perjury that the foregoing is true and correct. Executed on this 19th day of November 2012.

Respec y,

J..

Shea V

President, Nuclear Licensing

Enclosure:

Evaluation of Proposed Changes cc (Enclosure):

NRC Regional Administrator - Region II NRC Senior Resident Inspector-Watts Bar Nuclear Plant, Unit 1 NRC Senior Resident Inspector-Watts Bar Nuclear Plant, Unit 2 Director, Division of Radiological Health - Tennessee State Department of Environment and Conservation

ENCLOSURE EVALUATION OF PROPOSED CHANGES TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT UNIT I

Subject:

Watts Bar Nuclear Plant (WBN) Unit 1 - Application to Modify Technical Specification 3.7.10, "Control Room Emergency Ventilation System (CREVS)"

(WBN-TS-12-01) 1.0

SUMMARY

DESCRIPTION 2.0 DETAILED DESCRIPTION 2.1 Proposed Changes 2.2 Need for Proposed Changes

3.0 TECHNICAL EVALUATION

3.1

System Description

3.2 Evaluation

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements and Criteria 4.2 Precedent 4.3 Significant Hazards Consideration 4.4 Conclusions

5.0 ENVIRONMENTAL CONSIDERATION

ATTACHMENTS

1.

Proposed WBN Unit 1 TS Changes (Markups)

2.

Proposed WBN Unit I TS Bases Changes (Markups)

3.

Proposed WBN Unit I TS Changes (Final Typed)

4.

Proposed WBN Unit 1 TS Bases Changes (Final Typed)

I Page 1 of 8

ENCLOSURE EVALUATION OF PROPOSED CHANGES 1.0

SUMMARY

DESCRIPTION The Tennessee Valley Authority (TVA) is submitting a request for an amendment to Facility Operating License No. NPF-90 for Watts Bar Nuclear Plant (WBN) Unit 1. This license amendment request seeks approval to change the WBN Unit 1 Technical Specification (TS) 3.7.10 to require a unit shutdown within the TS 3.7.10 Actions instead of entering Limiting Condition for Operation (LCO) 3.0.3 when both Control Room Emergency Ventilation System (CREVS) trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met.

Attachments 1 and 2 to this enclosure provide the existing WBN Unit 1 TS pages and TS Bases pages marked up to show the proposed changes, respectively. Attachments 3 and 4 provide the existing WBN Unit I TS pages and TS Bases retyped to show the proposed changes, respectively.

2.0 DETAILED DESCRIPTION 2.1 Proposed Changes WBN Unit 1 TS 3.7.10 requires two independent CREVS trains to be OPERABLE in all MODES.

TS 3.7.10 Action E describes the Required Actions and Completion Time when two CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. Required Action E.1 requires restoration of one CREVS train to OPERABLE status with a Completion Time of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. However, there is no specific Required Action and Completion Time if Required Action E.1 and associated Completion Time is not met.

To clarify the Required Action for not meeting Required Action E.1 and associated Completion Time, a change is proposed to revise TS 3.7.10 to add a new Condition F to state:

F.

Required Action and associated Completion Time of Condition E not met.

The proposed Required Actions and Completion Times for the new Condition F state:

F.1 Be in MODE 3.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> AND F.2 Be in MODE 5.

36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> As a result of this change, the following conforming administrative changes to TS 3.7.10 Actions are required:

Current Condition F is changed to Condition G and current Required Action F.1 is changed to Required Action G.1.

Current Condition G is changed to Condition H and current Required Action G.1 is changed to Required Action H.1.

Page 2 of 8

ENCLOSURE EVALUATION OF PROPOSED CHANGES In addition, conforming changes to the TS 3.7.10 Bases are proposed. These changes are provided to the NRC for information only.

2.2 Need for Proposed Changes WBN Unit 1 TS 3.7.10 does not currently specify a Condition and associated Required Actions and Completion Times if Required Action E.1 and associated Completion Time is not met, which requires restoration of one CREVS train to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> if two CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. In this Condition, the requirements of LCO 3.0.3 would be required to be entered.

LCO 3.0.3 applies when an LCO is not met and an associated Action is not provided. However, current Action G states that if two CREVS trains are inoperable in MODE 1, 2, 3, or 4 for reasons other than Condition B or E, to enter LCO 3.0.3 immediately. With respect to current Condition E, the wording of Condition G could imply that an LCO 3.0.3 entry is only for reasons other than current Condition E (i.e., LCO 3.0.3 is not required to be entered if the Required Action and associated Completion Time of Condition E is not met). Therefore, there is a potential conflict in applying the appropriate actions for not meeting the Required Action and associated Completion Time of Condition E.

To resolve this potential conflict, a change is proposed to revise TS 3.7.10 to add a new Condition F to require specific shutdown Required Actions and Completion Times when the Required Action and associated Completion Time of Condition E is not met. This would preclude any misunderstanding by operations personnel as to whether or not LCO 3.0.3 is required to be entered in this case.

3.0 TECHNICAL EVALUATION

3.1

System Description

The CREVS is described in Sections 6.4 and 9.4.1 of the WBN Unit 1 Updated Final Safety Analysis Report (UFSAR). The CREVS provides a protected environment from which occupants can control the unit following an uncontrolled release of radioactivity, hazardous chemicals, or smoke. The Main Control Room Habitability Zone (MCRHZ) is designed to maintain a positive pressure relative to the outdoors and to the adjacent areas at all times, except during a tornado warning, to minimize air inleakage.

The CREVS consists of two independent, redundant trains that circulate and filter air in the MCRHZ (also known as the Control Room Envelope (CRE)). Each CREVS train consists of a high efficiency particulate air (HEPA) filter, an activated charcoal adsorber section for removal of gaseous activity (principally iodines), and a fan. Two independent, redundant Control Building emergency pressurization fans, each with their own outside air intake, are also part of the CREVS trains and pressurize the MCRHZ and maintain a minimum 1/8-inch positive pressure relative to the outdoors and adjoining spaces. A cross-connection is provided just upstream of the Control Building emergency pressurization fans which allows either fan to draw air from either emergency air intake, if necessary.

Actuation of the CREVS occurs automatically upon receipt of a safety injection signal or a control room air intake radiation monitor signal, which provides indication of high radiation in the outside air supply. Actuation of the CREVS in the emergency mode of operation closes the unfiltered outside air intake and unfiltered exhaust dampers and aligns the system for Page 3 of 8

ENCLOSURE EVALUATION OF PROPOSED CHANGES recirculation of the air within the MCRHZ through the redundant trains of air handling units, with a portion of the stream of air directed through HEPA and charcoal filters. The emergency mode also initiates pressurization and filtered ventilation of the air supply to the MCRHZ.

Pressurization of the MCRHZ prevents infiltration of unfiltered air from the surrounding areas of the building. A single CREVS train operating at a flow rate of 4000 cfm +/- 10% (which includes a pressurization flow of < 711 cfm) will pressurize the MCRHZ to a minimum of 0.125 inches water gauge relative to adjacent areas. However, during a tornado warning, the tornado dampers are closed which isolates the MCRHZ from the outside air supply, thus precluding the pressurization function of the CREVS.

3.2 Evaluation TS 3.7.10 Action E describes the Required Action and Completion Time when two CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. Required Action E.1 requires restoration of one CREVS train to OPERABLE status with a Completion Time of 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. TVA is proposing to require a unit shutdown within the TS 3.7.10 Actions instead of entering the shutdown requirements of LCO 3.0.3 when Required Action E. 1 and the associated Completion Time is not met.

As described in WBN Unit 1 UFSAR Section 9.4.1.1, tornado dampers are closed manually from, the Main Control Room (MCR) to protect the Control Building from tornado depressurization effects in the event of a tornado warning. Closing the tornado dampers results in inoperability of both CREVS trains, because the CREVS may not be capable of maintaining the MCRHZ to a minimum of 0.125 inches water gauge relative to adjacent areas with these tornado dampers closed. However, loss of MCRHZ pressurization during this time does not result in contaminated air leaking into the MCRHZ since a loss-of-coolant accident is not postulated concurrent with a tornado.

In the event of a tornado warning, and if one of the tornado dampers is not reopened within the 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> Completion Time of Required Action E.1, TS 3.7.10 does not provide any specific follow-up actions. Under this scenario, LCO 3.0.3 would be entered. LCO.3.0.3 requires action to be initiated within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> to be in MODE 3 in 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />, be in MODE 4 in 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br />, and be in MODE 5 within 37 hours4.282407e-4 days <br />0.0103 hours <br />6.117725e-5 weeks <br />1.40785e-5 months <br />.

The proposed change adds a specific requirement for a unit shutdown within the TS 3.7.10 Actions instead of entering LCO 3.0.3 when both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met. The proposed new Action F would apply in this situation, and proposed Required Actions F.1 and F.2 would require the unit to be in MODE 3 within a Completion Time of 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in MODE 5 within a Completion Time of 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />, respectively. This proposed new Action F provides a similar requirement as the current LCO 3.0.3 Action, in that the unit will be required to be placed in a subcritical condition (MODE 3) within a finite time and in cold shutdown (MODE 5) within a finite time. The proposed new Action F does not include the additional time (1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />) allowed by LCO 3.0.3 to be in the respective MODES, thus decreasing the Completion Times to be in MODE 3 and MODE 5 by 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. In addition, the proposed new Action F does not include the intermediate action to be in MODE 4 (i.e., less than 350 degrees F). This allowance (to include a specific shutdown action within TS 3.7.10) is consistent with TS 3.7.10 Action C that applies when the Required Actions of Condition B (which also could impact both CREVS trains) are not met within the associated Completion Time. The change is acceptable because the Page 4 of 8

ENCLOSURE EVALUATION OF PROPOSED CHANGES requirements to shutdown the unit to Mode 3 and Mode 5 are similar to the current requirements (with the exception of the intermediate Required Action and Completion Time to be in MODE 4),

and the required Completion Times are 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> less than the existing LCO 3.0.3 Completion Times that currently apply. Deletion of the intermediate action is acceptable since placing the unit in MODE 3 ensures the reactor is subcritical, and the requirement to be in MODE 5 will ensure the unit is cooled down to 200 degrees F.

The proposed changes to WBN Unit 1 TS 3.7.10, "CREVS," resolve a potential conflict in applying the appropriate actions for not meeting the Required Action and associated Completion Time of Condition E. These proposed changes are acceptable because the requirements to shutdown the unit to Mode 3 and Mode 5 are similar to the current requirements, the required Completion Times are 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> less than the existing LCO 3.0.3 Completion Times that currently apply, and do not impact the design and operation of the CREVS, or the ultimate Actions required to be taken by TS 3.7.10 upon inoperability of the CREVS in MODE 1, 2, 3, or4 due to actions taken as a result of a tornado warning. As such, there is no impact on the safety analysis for the CREVS.

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements and Criteria 10 CFR 50, Appendix A, General Design Criteria (GDC) 19, "Control Room," requires that a control room be provided from which actions can be taken to operate the nuclear power unit safely under normal conditions and to maintain it in a safe condition under accident conditions, including loss-of-coolant accidents. Adequate radiation protection shall 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 requirements of the proposed TS 3.7.10 changes conform to the above regulatory requirement.

The requirements for the Actions to be taken in the event of inoperability of the CREVS, and as presented in the proposed revision of the WBN Unit 1 TS, contains substantiated sufficient information pertaining to the Actions required to be taken by TS 3.7.10 upon inoperability of the CREVS in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning.

4.2 Precedent Sequoyah Nuclear Plant (SQN) Units 1 and 2 have similar TS Actions related to both CREVS trains being inoperable due to actions taken as a result of a tornado warning. SQN Units 1 and 2 TS 3.7.7 Action c in MODES 1, 2, 3 and 4 allows 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> to restore one CREVS train to OPERABLE status or be in HOT STANDBY (MODE 3) within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in COLD SHUTDOWN (MODE 5) within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br /> (Note that the SQN TS are not in the Improved Standard Technical Specification format). Thus, the unit shutdown required if the 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> is exceeded is in the TS 3.7.7 Actions, and does not require entry into LCO 3.0.3. This allowance was approved by the NRC in SQN License Amendments 187 and 179 (TAC Nos. M89495 and M89496), dated October 17, 1994 (ADAMS Accession No. ML013310385).

Thus, this requested change would ensure the WBN Unit 1 TS 3.7.10 has similar shutdown requirements as SQN Units 1 and 2 TS 3.7.7, which is another TVA plant.

Page 5 of 8

ENCLOSURE EVALUATION OF PROPOSED CHANGES 4.3 Significant Hazards Consideration The proposed changes modify WBN Unit 1 TS 3.7.10 to resolve a potential conflict in applying the appropriate actions for not meeting the Required Action and associated Completion Time of Condition E. TVA proposes to modify TS 3.7.10 to require a unit shutdown within the TS 3.7.10 Actions instead of entering LCO 3.0.3 when both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met.

These proposed changes are acceptable in the event that both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met because the requirements to shutdown the unit to Mode 3 and Mode 5 are similar to the current requirements, the required Completion Times are 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> less than the existing LCO 3.0.3 Completion Times that currently apply, and do not impact the design and operation of the CREVS, or the ultimate Actions required to be taken by TS 3.7.10 upon inoperability of the CREVS in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning.

The proposed changes do not alter the technical requirements presented in the WBN Unit 1 TS that describe applicable actions to be taken to shutdown the unit in the event that both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met. No physical changes to safety-related systems, structures, or components are required.

The TVA has concluded that the changes to WBN Unit 1 TS do not involve a significant hazards consideration. TVA's conclusion is based on its evaluation in accordance with 10 CFR 50.91 (a)(1) of the three standards set forth in 10 CFR 50.92, "Issuance of Amendment,"

as discussed below:

1.

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

Response: No.

The proposed changes modify WBN Unit 1 TS 3.7.10 to resolve a potential conflict in applying the appropriate actions for not meeting the Required Action and associated Completion Time of Condition E. These proposed changes are acceptable in the event that both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met because the requirements to shutdown the unit to Mode 3 and Mode 5 are similar to the current requirements, the required Completion Times are 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> less than the existing LCO 3.0.3 Completion Times that currently apply, and do not impact the design and operation of the CREVS, or the ultimate Actions required to be taken by TS 3.7.10 upon inoperability of the CREVS in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. The proposed changes do not 1) require physical changes to plant systems, structures, or components; 2) prevent the safety function of any safety-related system, structure, or component during a design basis event; 3)

Page 6 of 8

ENCLOSURE EVALUATION OF PROPOSED CHANGES alter, degrade, or prevent action described or assumed in any accident described in the WBN Unit 1 UFSAR from being performed since the safety-related systems, structures, or components are not modified; 4) alter any assumptions previously made in evaluating radiological consequences; or 5) affect the integrity of any fission product barrier.

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

2.

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

Response: No.

The proposed changes modify WBN Unit 1 TS 3.7.10 to resolve a potential conflict in applying the appropriate, actions for not meeting the Required Action and associated Completion Time of Condition E. These proposed changes are acceptable in the event that both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met because the requirements to shutdown the unit to Mode 3 and Mode 5 are similar to the current requirements, the required Completion Times are 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> less than the existing LCO 3.0.3 Completion Times that currently apply, and do not impact the design and operation of the CREVS, or the ultimate Actions required to be taken by TS 3.7.10 upon inoperability of the CREVS in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. The proposed changes do not introduce any new accident causal mechanisms, since no physical changes are being made to the plant, nor do they impact any plant systems that are potential accident initiators.

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

3.

Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No.

The proposed changes modify WBN Unit 1 TS 3.7.10 to resolve a potential conflict in applying the appropriate actions for not meeting the Required Action and associated Completion Time of Condition E. These proposed changes are acceptable in the event that both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met because the requirements to shutdown the unit to Mode 3 and Mode 5 are similar to the current requirements, the required Completion Times are 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> less than the existing LCO 3.0.3 Completion Times that currently apply, and do not impact the design and operation of the CREVS, or the ultimate Actions required to be taken by TS 3.7.10 upon inoperability of the CREVS in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. As such, there is no impact on the safety analysis for the CREVS. The proposed changes do not alter the permanent plant design, Page 7 of 8

ENCLOSURE EVALUATION.OF PROPOSED CHANGES including instrument set points, that is the basis of the assumptions contained in the safety analyses.

Therefore, the proposed changes do not involve a significant reduction in a margin of safety.

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 to the health and safety of the public.

5.0 ENVIRONMENTAL CONSIDERATION

A review 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, or would change an inspection or surveillance requirement. 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 effluents 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(c)(9). Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.

Page 8 of 8

ENCLOSURE EVALUATION OF PROPOSED CHANGES ATTACHMENT 1 Proposed WBN Unit I TS Changes (Markups)

CREVS 3.7.10 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C.

Required Action and C.1 Be in MODE 3.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time of Condition A or B AND not met in MODE 1, 2, 3, or 4.

C.2 Be in MODE 5.

36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> D.

Required Action and D.1 Place OPERABLE CREVS Immediately associated Completion train in emergency mode.

Time of Condition A not met in MODE 5 or 6, or during OR movement of irradiated fuel assemblies.

D.2 Suspend movement of Immediately irradiated fuel assemblies.

E.

Two CREVS trains E.1 Restore one CREVS train to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> inoperable in MODE 1, 2, 3, OPERABLE status.

or 4 due to actions taken as a result of a tornado warning.

I I

I I

Two CREVS trains inoperable in MODE 5 or 6, or during movement of irradiated fuel assemblies.

1 j~J Suspend movement of irradiated fuel assemblies.

Immediately OR One or more CREVS trains inoperable due to inoperable CRE boundary in Mode 5 or 6, or during movement of irradiated fuel assemblies.

(continued)

Wafts Bar-Unit 1 3.7-23 Amendment 35, 70

INSERT 1 F. Required Action and associated Completion Time of Condition E not met.

F.1 AND F.2 Be in MODE 3.

Be in MODE 5.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> 36 hours

CREVS 3.7.10 I

I ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME Two CREVS trains

• .1 Enter LCO 3.0.3.

Immediately inoperable in MODE 1,2, 3, or 4 for reasons other than Condition B or E.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.10.1 Operate each CREVS train for > 15 minutes.

31 days SR 3.7.10.2 Perform required CREVS filter testing in accordance with the In accordance with Ventilation Filter Testing Program (VFTP).

the VFTP SR 3.7.10.3 Verify each CREVS train actuates on an actual or simulated 18 months actuation signal.

SR 3.7.10.4 Perform required CRE unfiltered air inleakage testing in In accordance with accordance with the Control Room Habitability Program.

the Control Room Envelope Habitability Program I

Watts Bar-Unit 1 3.7-24 Amendment 70

ENCLOSURE EVALUATION OF PROPOSED CHANGES ATTACHMENT 2 Proposed WBN Unit 1 TS Bases Changes (Markups)

CREVS B 3.7.10 BASES (continued)

ACTIONS (continued) intentional or unintentional. The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time is reasonable based on the low probability of a DBA occurring during this time period, and the use of mitigating actions. The 90 day Completion Time is reasonable based on the determination that the mitigating actions will ensure protection of CRE occupants within analyzed limits while limiting the probability that CRE occupants will have to implement protective measures that may adversely affect their ability to control the reactor and maintain it in a safe shutdown condition in the event of a DBA. In addition, the 90 day Completion Time is a reasonable time to diagnose, plan and possibly repair, and test most problems with the CRE boundary.

C.1 and C.2 In MODE 1, 2, 3, or 4, if the inoperable CREVS train or the CRE boundary cannot be restored to OPERABLE status within the required Completion Time, the plant must be placed in a MODE that minimizes accident risk. To achieve this status, the plant must be placed in at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

D.1 and D.2 In MODE 5 or 6, or during movement of irradiated fuel assemblies, if the inoperable CREVS train cannot be restored to OPERABLE status within the required Completion Time, action must be taken to immediately place the OPERABLE CREVS train in the emergency mode. This action ensures that the remaining train is OPERABLE, that no failures preventing automatic actuation will occur, and that any active failure would be readily detected.

An alternative to Required Action D.1 is to immediately suspend activities that could result in a release of radioactivity that might require isolation of the CRE.

This places the unit in a condition that minimizes the accident risk. This does not preclude the movement of fuel to a safe position.

E.1 If both CREVS trains are inoperable in MODE 1, 2, 3, or 4, due to actions taken as a result of a tornado, the CREVS may not be capable of performing the intended function because of loss of pressurizing air to the control room. At least one train must be restored to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> restoration time is considered reasonable considering the low probability of occurrence of a design basis accident concurrent with a tornado warning.-If the d st

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t be mpleted w h the

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LC:

9.6.511 itii be e cnn ed.

(continued)

Watts Bar-Unit 1 B 3.7-55 Revision 45, 91, 117 Amendment 35, 70

CREVS B 3.7.10 BASES ACTIONS

-E4-(eeninwedý-

IBASES INSERT I The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

In MODE 5 or 6, or during movement of irradiated fuel assemblies with two CREVS trains inoperable or with one or more CREVS trains inoperable due to an inoperable CRE boundary, action must be taken immediately to suspend activities that could result in a release of radioactivity that might require isolation of the CRE. This places the unit in a condition that minimizes the accident risk.

This does not preclude the movement of fuel to a safe position.

• J-6e.1 If both CREVS trains are inoperable in MODE 1, 2, 3, or 4, for reasons other than Condition B or Condition E the CREVS may not be capable of performing the intended function and the plant is in a condition outside the accident analyses.

Therefore, LCO 3.0.3 must be entered immediately.

SURVEILLANCE SR 3.7.10.1 REQUIREMENTS Standby systems should be checked periodically to ensure that they function properly. As the environment and normal operating conditions on this system are not too severe, testing each train once every month provides an adequate check of this system. The systems need only be operated for > 15 minutes to demonstrate the function of the system. The 31 day Frequency is based on the reliability of the equipment and the two train redundancy.

SR 3.7.10.2 This SR verifies that the required CREVS testing is performed in accordance with the Ventilation Filter Testing Program (VFTP). The CREVS filter tests are in accordance with Regulatory Guide 1.52 (Ref. 6). The VFTP includes testing the performance of the HEPA filter, charcoal adsorber efficiency, minimum flow rate, and the physical properties of the activated charcoal. Specific test Frequencies and additional information are discussed in detail in the VFTP.

(continued)

Watts Bar-Unit 1 B 3.7-56 Revision 91 Amendment 70

BASES INSERT 1 F.1 and F.2 If one CREVS train cannot be restored to OPERABLE status within the associated Completion Time of Condition E, the plant must be placed in a MODE that minimizes accident risk. To achieve this status, the plant must be placed in at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.

ENCLOSURE EVALUATION OF PROPOSED CHANGES ATTACHMENT 3 Proposed WBN Unit 1 TS Changes (Final Typed)

(

CREVS 3.7.10 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME C.

Required Action and C.1 Be in MODE 3.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time of Condition A or B AND not met in MODE 1, 2, 3, or 4.

C.2 Be in MODE 5.

36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> D.

Required Action and D.1 Place OPERABLE CREVS Immediately associated Completion train in emergency mode.

Time of Condition A not met in MODE 5 or 6, or during OR movement of irradiated fuel assemblies.

D.2 Suspend movement of Immediately irradiated fuel assemblies.

E.

Two CREVS trains E.1 Restore one CREVS train to 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> inoperable in MODE 1, 2, 3, OPERABLE status.

or 4 due to actions taken as a result of a tornado warning.

F.

Required Action and F.1 Be in MODE 3.

6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> associated Completion Time of Condition E not AND met.

F.2 Be in MODE 5.

36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br /> (continued)

Wafts Bar-Unit 1 3.7-23 Amendment 35, 70,

CREVS 3.7.10 ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME G.

Two CREVS trains G.1 Suspend movement of Immediately inoperable in MODE 5 or 6, irradiated fuel assemblies.

or during movement of irradiated fuel assemblies.

OR One or more CREVS trains inoperable due to inoperable CRE boundary in Mode 5 or 6, or during movement of irradiated fuel assemblies.

H.

Two CREVS trains H.1 Enter LCO 3.0.3.

Immediately inoperable in MODE 1, 2, 3, or 4 for reasons other than Condition B or E.

SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.7.10.1 Operate each CREVS train for > 15 minutes.

31 days SR 3.7.10.2 Perform required CREVS filter testing in accordance with the In accordance with Ventilation Filter Testing Program (VFTP).

the VFTP SR 3.7.10.3 Verify each CREVS train actuates on an actual or simulated 18 months actuation signal.

Watts Bar-Unit 1 3.7-24 Amendment 70,

ENCLOSURE EVALUATION OF PROPOSED CHANGES ATTACHMENT 4 Proposed WBN Unit I TS Bases Changes (Final Typed)

CREVS B 3.7.10 BASES (continued)

ACTIONS (continued) intentional or unintentional. The 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> Completion Time is reasonable based on the low probability of a DBA occurring during this time period, and the use of mitigating actions. The 90 day Completion Time is reasonable based on the determination that the mitigating actions will ensure protection of CRE occupants within analyzed limits while limiting the probability that CRE occupants will have to implement protective measures that may adversely affect their ability to control the reactor and maintain it in a safe shutdown condition in the event of a DBA. In addition, the 90 day Completion Time is a reasonable time to diagnose, plan and possibly repair, and test most problems with the CRE boundary.

C.1 and C.2 In MODE 1, 2, 3, or 4, if the inoperable CREVS train or the CRE boundary cannot be restored to OPERABLE status within the required Completion Time, the plant must be placed in a MODE that minimizes accident risk. To achieve this status, the plant must be placed in at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

D.1 and D.2 In MODE 5 or 6, or during movement of irradiated fuel assemblies, if the inoperable CREVS train cannot be restored to OPERABLE status within the required Completion Time, action must be taken to immediately place the OPERABLE CREVS train in the emergency mode. This action ensures that the remaining train is OPERABLE, that no failures preventing automatic actuation will occur, and that any active failure would be readily detected.

An alternative to Required Action D.1 is to immediately suspend activities that could result in a release of radioactivity that might require isolation of the CRE.

This places the unit in a condition that minimizes the accident risk. This does not preclude the movement of fuel to a safe position.

E. 1 If both CREVS trains are inoperable in MODE 1, 2, 3, or 4, due to actions taken as a result of a tornado, the CREVS may not be capable of performing the intended function because of loss of pressurizing air to the control room. At least one train must be restored to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> restoration time is considered reasonable considering the low probability of occurrence of a design basis accident concurrent with a tornado warning.

(continued)

I Wafts Bar-Unit 1 B 3.7-55 Revision 45, 91, 117, Amendment 35, 70,

CREVS B 3.7.10 BASES ACTIONS F.1 and F.2 If one CREVS train cannot be restored to OPERABLE status within the associated Completion Time of Condition E, the plant must be placed in a MODE that minimizes accident risk. To achieve this status, the plant must be placed in at least MODE 3 within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and in MODE 5 within 36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />. The allowed Completion Times are reasonable, based on operating experience, to reach the required plant conditions from full power conditions in an orderly manner and without challenging plant systems.

G.1 In MODE 5 or 6, or during movement of irradiated fuel assemblies with two CREVS trains inoperable or with one or more CREVS trains inoperable due to an inoperable CRE boundary, action must be taken immediately to suspend activities that could result in a release of radioactivity that might require isolation of the CRE. This places the unit in a condition that minimizes the accident risk.

This does not preclude the movement of fuel to a safe position.

H.1 If both CREVS trains are inoperable in MODE 1, 2, 3, or 4, for reasons other than Condition B or Condition E the CREVS may not be capable of performing the intended function and the plant is in a condition outside the accident analyses.

Therefore, LCO 3.0.3 must be entered immediately.

SURVEILLANCE SR 3.7.10.1 REQUIREMENTS Standby systems should be checked periodically to ensure that they function properly. As the environment and normal operating conditions on this system are not too severe, testing each train once every month provides an adequate check of this system. The systems need only be operated for > 15 minutes to demonstrate the function of the system. The 31 day Frequency is based on the reliability of the equipment and the two train redundancy.

SR 3.7.10.2 This SR verifies that the required CREVS testing is performed in accordance with the Ventilation Filter Testing Program (VFTP). The CREVS filter tests are in accordance with Regulatory Guide 1.52 (Ref.: 6). The VFTP includes testing the performance of the HEPA filter, charcoal adsorber efficiency, minimum flow rate, and the physical properties of the activated charcoal. Specific test Frequencies and additional information are discussed in detail in the VFTP.

(continued)

Watts Bar-Unit 1 B 3.7-56 Revision 91, Amendment 70,

NSRB

SUMMARY

SHEET Document Name:

Watts Bar Nuclear Plant (WBN) Unit 1 Application to Modify Technical Specification 3.7.10, "Control Room Emergency Ventilation System (CREVS)"

Document Number & Proposed Revision Number:

WBN-TS-12-01 Proposed Effective Date:

11/08/2012 Summary of Changes Proposed:

This license amendment request seeks approval to change the WBN Unit 1 Technical Specification (TS) 3.7.10 to require a unit shutdown within the TS 3.7.10 Actions instead of entering Limiting Condition for Operation (LCO) 3.0.3 when both Control Room Emergency Ventilation System (CREVS) trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met.

Reason for Proposed Changes:

WBN Unit 1 TS 3.7.10 does not currently specify a Condition and associated Required Actions and Completion Times if Required Action E.1 and associated Completion Time is not met, which requires restoration of one CREVS train to OPERABLE status within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> if two CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. In this Condition, the requirements of LCO 3.0.3 would be required to be entered. LCO 3.0.3 applies when an LCO is not met and an associated Action is not provided. However, current Action G states that if two CREVS trains are inoperable in MODE 1, 2, 3, or 4 for reasons other than Condition B or E, to enter LCO 3.0.3 immediately. With respect to current Condition E, the wording of Condition G could imply that an LCO 3.0.3 entry is only for reasons other than current Condition E (i.e., LCO 3.0.3 is not required to be entered if the Required Action and associated Completion Time of Condition E is not met). Therefore, there is a potential conflict in applying the appropriate actions for not meeting the Required Action and associated Completion Time of Condition E. To resolve this potential conflict, a change is proposed to revise TS 3.7.10 to add a new Condition F to require specific shutdown Required Actions and Completion Times when the Required Action and associated Completion Time of Condition E is not met. This would preclude any misunderstanding by operations personnel as to whether or not LCO 3.0.3 is required to be entered in this case.

TVA 41030 [02-20101 Page 1 of 1 NLDP-1-6 [02-09-2010]

Impact to Nuclear Safety:

The proposed changes modify WBN Unit 1 TS 3.7.10 to resolve a potential conflict in applying the appropriate actions for not meeting the Required Action and associated Completion Time of Condition E. These proposed changes are acceptable in the event that both CREVS trains are inoperable in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning and 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 restoration of at least one CREVS train to OPERABLE status is not met because the requirements to shutdown the unit to Mode 3 and Mode 5 are similar to the current requirements, the required Completion Times are 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> less than the existing LCO 3.0.3 Completion Times that currently apply, and do not impact the design and operation of the CREVS, or the ultimate Actions required to be taken by TS 3.7.10 upon inoperability of the CREVS in MODE 1, 2, 3, or 4 due to actions taken as a result of a tornado warning. The proposed changes do not 1) require physical changes to plant systems, structures, or components; 2) prevent the safety function of any safety related system, structure, or component during a design basis event; 3) alter, degrade, or prevent action described or assumed in any accident described in the WBN Unit 1 UFSAR from being performed since the safety related systems, structures, or components are not modified; 4) alter any assumptions previously made in evaluating radiological consequences; or 5) affect the integrity of any fission product barrier. The proposed changes do not introduce any new accident causal mechanisms, since no physical changes are being made to the plant, nor do they impact any plant systems that are potential accident initiators. The proposed changes do not alter the permanent plant design, including instrument set points, that is the basis of the assumptions contained in the safety analyses.

Therefore, this proposed amendment does not 1) involve a significant increase in the probability or consequences of an accident previously evaluated; 2) create the possibility of a new or different kind of accident from any accident previously evaluated; and 3) involve a significant reduction in a margin of safety.

Documents Provided to NSRB:

License Amendment Request Presenter Name:

Telephone:

Pager:

George Wadkins 865-805-3085 N/A (Comments/questions should be provided to Presenter listed above as soon as possible to facilitate resolution prior to NSRB review.)

TVA 41030 [10-2408]

Page 2 of 2 NLDP-1-6 [10-22-2008]