Watts Bar, Units 1 and 2 - Application to Revise Technical ...Tennessee Valley Authority, 1101...

Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402

CNL-16-148

November 23, 2016

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

Watts Bar Nuclear Plant, Unit 2 Facility Operating License No. NPF-96 NRC Docket No. 50-391

Subject: Application to Revise Technical Specifications to Adopt TSTF-547, Revision 1, “Clarification of Rod Position Requirements” (WBN-TS-16-025)

Pursuant to Title 10 of the Code of Federal Regulations (CFR), Section 50.90, Tennessee Valley Authority (TVA) is submitting a request for an amendment to the Technical Specifications (TS) for the Watts Bar Nuclear Plant (WBN), Unit 1 and Unit 2.

The proposed amendment revises the requirements on control and shutdown rods, and rod and bank position indication. The proposed amendment adopts the changes contained in Technical Specification Task Force (TSTF) - 547, Revision 1, “Clarification of Rod Position Requirements,” with minor variations as described in Attachment 1. Attachment 1 provides a description and assessment of the proposed changes. Attachments 2 and 3 provide the existing respective WBN Unit 1 and Unit 2 TS pages marked up to show the proposed changes. Attachments 4 and 5 provide the revised (clean) respective WBN Unit 1 and Unit 2 TS pages. Attachments 6 and 7 provide the existing respective WBN Unit 1 and Unit 2 TS Bases pages marked to show the proposed changes for information only.

The WBN Plant Operations Review Committee and the TVA Nuclear Safety Review Board have reviewed this proposed change and determined that operation of WBN Unit 1 and Unit 2 in accordance with the proposed change will not endanger the health and safety of the public.

L44 161123 002

U. S. Nuclear Regulatory Commission CNL-16-148 Page 2 November 23, 2016

TV A requests approval of the proposed TS change within 12 months of the date of this letter. The requested review period is consistent with NRC guidance and supports plans for implementation. Once approved, the amendment will be fully implemented within 60 days.

TVA has determined that there are no significant hazards consideration associated with the proposed change and that the TS change qualifies for a categorical exclusion from environmental review pursuant to the provisions of 10 CFR 51.22(c)(9). Additionally, in accordance with 1 O CFR 50.91 (b)(1 ), TVA is sending a copy of this letter and enclosures to the Tennessee State Department of Environment and Conservation.

Please address any questions regarding this request to Edward D. Schrull at (423) 751-3850.

I declare under penalty of perjury that the foregoing is true and correct. Executed on this 23rd day of November 2016.

Respectfully,

~~~ J . W. Shea Vice President, Nuclear Licensing

Attachments: 1. Description and Assessment 2. Proposed Technical Specification Changes (Mark-Up} for WBN Unit 1 3. Proposed Technical Specification Changes (Mark-Up) for WBN Unit 2 4. Revised Technical Specification Pages (Final Typed) for WBN Unit 1 5. Revised Technical Specification Pages (Final Typed) for WBN Unit 2 6. Proposed Technical Specification Bases Changes (Mark-Up) for WBN Unit 1

(For Information Only) 7. Proposed Technical Specification Bases Changes (Mark-Up) for WBN Unit 2

(For Information Only)

cc (Attachments):

NRC Regional Administrator - Region II NRC Senior Resident Inspector - Watts Bar Nuclear Plant NRC Project Manager- Watts Bar Nuclear Plant Director, Division of Radiological Health - Tennessee State Department of Environment

and Conservation (w/o attachments)

ATTACHMENT 1 - DESCRIPTION AND ASSESSMENT

CNL-16-148 A1-1

1.0 DESCRIPTION The proposed amendment revises the requirements on control and shutdown rods, and rod and bank position indication in the Watts Bar Nuclear (WBN) Plant, Unit 1 and Unit 2 Technical Specification (TS) 3.1.5, "Rod Group Alignment Limits," TS 3.1.6, "Shutdown Bank Insertion Limits," TS 3.1.7, "Control Bank Insertion Limits," and TS 3.1.8, "Rod Position Indication," to provide time to repair rod movement failures that do not affect rod Operability, to provide time for analog position indication instruments to read accurately after rod movement, to correct conflicts between the TS, to eliminate an unnecessary action, and to increase consistency and to improve the presentation.

2.0 ASSESSMENT

2.1 Applicability of Safety Evaluation

The Tennessee Valley Authority (TVA) has reviewed the safety evaluation for Technical Specifications Task Force 547 (TSTF-547), Revision 1 provided to the TSTF in a letter dated March 4, 2016. This review included a review of the Nuclear Regulatory Commission (NRC) staff’s evaluation, as well as the information provided in TSTF-547, Revision 1. As described in the subsequent paragraphs, TVA has concluded that the justifications presented in the TSTF-547, Revision 1 proposal and the safety evaluation prepared by the NRC staff are applicable to WBN Unit 1 and Unit 2, and justify this amendment for the incorporation of the changes to the WBN Unit 1 and Unit 2 TS.

2.2 Variations

TVA is proposing the following minor variations from the TS changes described in TSTF-547, Revision 1. These variations do not affect the applicability of TSTF-547, Revision 1 or the NRC staff's safety evaluation to the proposed license amendment.

1. The WBN Unit 1 and Unit 2 TS utilize different numbering than the Standard

Technical Specifications on which TSTF-547, Revision 1 was based. The following table summarizes the differences between the WBN Unit 1 and Unit 2 TS numbering and the TSTF-547, Revision 1 numbering and titles.

TSTF-547, Rev. 1 WBN Unit 1 WBN Unit 2

TS 3.1.4, "Rod Group Alignment Limits"



TS 3.1.5, "Shutdown Bank Insertion Limits"

TS 3.1.6, “Shutdown Bank Insertion Limits”

TS 3.1.6, “Shutdown Bank Insertion Limits”

TS 3.1.6, "Control Bank Insertion Limits"



TS 3.1.7, "Rod Position Indication"



The use of different numbering does not affect the applicability of TSTF-547, Revision 1 to the WBN Unit 1 and Unit 2 TS.


CNL-16-148 A1-2

2. TSTF-547, Revision 1, TS 3.1.7, “Rod Position Indication,” Required Actions A.1 and

C.1 discuss indirect verification of rod position by using moveable incore detectors when the rod position indication system is inoperable. As described in Section 7.7.1.9 of the WBN Dual Unit Updated Final Safety Analysis Report, WBN Unit 1 and Unit 2 have a power distribution monitoring system (PDMS) that can be utilized to obtain a three-dimensional power distribution measurement to indirectly provide rod position verification. WBN Unit 1 has the ability to indirectly verify rod position utilizing either a moveable incore system or the PDMS (References 1 and 2). WBN Unit 2 uses the fixed incore system as input to PDMS to indirectly verify rod position (Reference 3). Accordingly, the proposed WBN Unit 1 and Unit 2 TS 3.1.8, “Rod Positon Indication” and associated TS Bases refer to utilizing the PDMS or moveable incore detectors for WBN Unit 1 and the PDMS for WBN Unit 2 in order to provide indirect verification of rod position for an inoperable rod indicator. TVA has determined that the variation from TSTF-547 to continue allowing the use of the PDMS to indirectly verify rod position does not affect the applicability of TSTF-547, Revision 1 to the WBN Unit 1 and Unit 2 TS.

3. TSTF-547, Revision 1, Surveillance Requirement (SR) 3.1.4.3 contains a value for

Tavg of 500oF, whereas the current WBN value (in SR 3.1.5.3) is 551oF. The temperature of 551oF represents a WBN Unit 1 plant-specific historical artifact of the licensing evolution process as the WBN Unit 1 TS transitioned from NUREG-0452, Revision 4 to NUREG-1431, Revision 0 (the Westinghouse Standard Technical Specifications), which kept the value at 551oF. The SR to demonstrate rod drop time was initially based on performing the test with all reactor coolant pumps operating and the average moderator temperature ≥ 551oF to simulate a reactor trip under actual conditions. WBN Unit 2 also specifies the 551oF temperature.

TVA has determined that the variation of the temperature specified in SR 3.1.4.3

(TVA proposed SR 3.1.5.3) is consistent with the current licensing basis of the plants and does not affect the applicability of TSTF-547, Revision 1 to the WBN Unit 1 and Unit 2 TS.

4. Incorporation of specific WBN minor format variations:

• Indentation of “OR” between TS 3.1.5, Required Action B.1.1 and B.1.2. • Addition of the word “overlap” in TS 3.1.7, Required Action A.3, which was

inadvertently left out of the TSTF-547 template. Note that the word “overlap” is correctly contained in and consistent with Limiting Condition for Operation (LCO) 3.1.7, TS 3.1.7 Conditions A. and C., TS 3.1.7 Required Action C.2, and SR 3.1.7.3.

These differences are administrative and do not affect the applicability of TSTF-547, Revision 1 to the WBN Unit 1 and Unit 2 TS.

Therefore, TVA is not proposing any significant variations or deviations from the TS changes described in TSTF-547, Revision 1 or the applicable parts of the NRC staff’s Safety Evaluation.


CNL-16-148 A1-3

The Traveler and safety evaluation discuss the applicable regulatory requirements and guidance, including the 10 CFR 50, Appendix A, General Design Criteria (GDC). WBN Unit 1 and Unit 2 were designed to meet the intent of the “Proposed General Design Criteria for Nuclear Power Plant Construction,” published for comment in the Federal Register on July 11, 1967 (32 FR 10213). The WBN Unit 1 and Unit 2 construction permit was issued in January 1973. UFSAR Section 3.1, “Conformance with NRC General Design Criteria,” addresses the NRC General Design Criteria published as Appendix A to 10 CFR 50 in July 1971, including Criterion 4 as amended October 27, 1987. This difference does not alter the conclusion that the proposed change is applicable to WBN Unit 1 and Unit 2. 3.0 REGULATORY ANALYSIS

3.1 No Significant Hazards Consideration Analysis

TVA requests adoption of TSTF-547, Revision 1, "Clarification of Rod Position Requirements," which is an approved change to the Standard Technical Specifications, into the Watts Bar Nuclear Plant, Unit 1 and Unit 2 Technical Specifications (TS). The proposed change revises the requirements on control and shutdown rods, and rod and bank position indication to provide time to repair rod movement failures that do not affect rod Operability, to provide time for analog position indication instruments to read accurately after rod movement, to correct conflicts between the TS, to eliminate an unnecessary action, and to increase consistency and to improve the presentation.

TVA has evaluated whether or not a significant hazards consideration is involved with the proposed amendment(s) by focusing on 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

consequences of an accident previously evaluated?

Response: No

Control and shutdown rods are assumed to insert into the core to shut down the reactor in evaluated accidents. Rod insertion limits ensure that adequate negative reactivity is available to provide the assumed shutdown margin (SDM). Rod alignment and overlap limits maintain an appropriate power distribution and reactivity insertion profile.

Control and shutdown rods are initiators to several accidents previously evaluated, such as rod ejection. The proposed change does change the limiting conditions for operation for the rods and makes technical changes to the Surveillance Requirements (SRs) governing the rods. However, the proposed change has no significant effect on the probability of any accident previously evaluated.

Revising the TS Actions to provide a limited time to repair rod movement control has no effect on the SDM assumed in the accident analysis as the proposed Action require verification that SDM is maintained. The effects on power distribution will not cause a significant increase in the consequences of any accident previously evaluated as all TS requirements on power distribution continue to be applicable. Revising the TS Actions to provide an alternative to frequent use of the moveable


CNL-16-148 A1-4

incore detector system to verify the position of rods with inoperable rod position indicator does not change the requirement for the rods to be aligned and within the insertion limits.

Therefore, the assumptions used in any accidents previously evaluated are unchanged and there is no significant increase in the consequences.

The consequences of an accident that might occur during the 1-hour period provided for the analog rod position indication to stabilize after rod movement are no different than the consequences of the accident under the existing actions with the rod declared inoperable.

The proposed change to resolve the conflicts in the TS ensure that the intended Actions are followed when equipment is inoperable. Actions taken with inoperable equipment are not assumptions in the accidents previously evaluated and have no significant effect on the consequences.

The proposed change to eliminate an unnecessary action has no effect on the consequences of accidents previously evaluated as the analysis of those accidents did not consider the use of the action.

The proposed change to increase consistency within the TS has no effect on the consequences of accidents previously evaluated as the proposed change clarifies the application of the existing requirements and does not change the intent.

Therefore, the proposed change 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 previously evaluated?

Response: No The proposed change does not involve a physical alteration of the plant (i.e., no new or different type of equipment will be installed). The change does not alter assumptions made in the safety analyses. The proposed change does alter the limiting conditions for operation for the rods and makes technical changes to the SRs governing the rods. However, the proposed change to actions maintains or improves safety when equipment is inoperable and does not introduce new failure modes.

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

3. Does the proposed amendment involve a significant reduction in a margin of

safety?

Response: No

The proposed change to allow time for rod position indication to stabilize after rod


CNL-16-148 A1-5

movement and to allow an alternative method of verifying rod position has no effect on the safety margin as actual rod position is not affected. The proposed change to provide time to repair rods that are Operable but immovable does not result in a significant reduction in the margin of safety because all rods must be verified to be Operable, and all other banks must be within the insertion limits. The remaining proposed changes to make the requirements internally consistent and to eliminate unnecessary actions do not affect the margin of safety as the changes do not affect the ability of the rods to perform their specified safety function. Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, TVA concludes that the proposed change presents no 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.

3.2 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.

4.0 ENVIRONMENTAL EVALUATION

The proposed change 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 change 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 change 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 change.

5.0 REFERENCES

1. NRC letter to TVA, “Watts Bar Nuclear Plant Unit 1 - Issuance of Amendment Regarding the Application to Implement BEACON Core Power Distribution and Monitoring System (TAC No. ME1698),” dated October 27, 2009 (ML092710381)

2. NRC letter to TVA, “Watts Bar Nuclear Plant Unit 1 - Issuance of Amendment Regarding Alternate Means for Monitoring Control or Shutdown Rod Positions (TAC No. MC1419) (WBN-TS-03-12),” dated September 20, 2005 (ML052300162)

3. Watts Bar Nuclear Plant Unit 2, Technical Specification 3.1.8, “Rod Positon Indication,” Facility Operating License No. NPF-96, dated October 22, 2015 (ML15251A587)

CNL-16-148 A2-1

ATTACHMENT 2 - PROPOSED TECHNICAL SPECIFICATION CHANGES (MARK-UP) FOR WBN UNIT 1

Rod Group Alignment Limits 3.1.5

Watts Bar-Unit 1 3.1-8 Amendment No. XX

3.1 REACTIVITY CONTROL SYSTEMS 3.1.5 Rod Group Alignment Limits LCO 3.1.5 All shutdown and control rods shall be OPERABLE., with all individual indicated

rod positions within 12 steps of their group step counter demand position. AND

Individual indicated rod positions shall be within 12 steps of their group step counter demand position.

APPLICABILITY: MODES 1 and 2. ACTIONS

CONDITION REQUIRED ACTION COMPLETION TIME A. One or more rod(s)

untrippableinoperable.

A.1.1 Verify SDM is ≥ 1.6% ∆k/kto

be within the limits specified in the COLR.

OR A.1.2 Initiate boration to restore

SDM to within limit. AND A.2 Be in MODE 3.

1 hour 1 hour 6 hours

B. One rod not within alignment limits.

B.1 Restore rod to within

alignment limits. OR B.2.1.1B.1.1 Verify SDM is

≥ 1.6% ∆k/kto be within the limits specified in the COLR.

OR B.2.1.2B.1.2 Initiate

boration to restore SDM to within limit.

AND

1 hour 1 hour 1 hour

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. (continued)

B.2.2 Reduce THERMAL

POWER to ≤ 75% RTP. AND B.2.3 Verify SDM is

≥ 1.6% ∆k/kwithin the limits specified in the COLR.

AND B.2.4 Perform SR 3.2.1.1, SR

3.2.1.2, and SR 3.2.2.1. AND B.2.5 Perform SR 3.2.2.1. AND B.2.65 Re-evaluate safety

analyses and confirm results remain valid for duration of operation under these conditions.

2 hours Once per 12 hours 72 hours 72 hours 5 days

C. Required Action and

associated Completion Time of Condition B not met.

C.1 Be in MODE 3.

6 hours

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME D. More than one rod not within

alignment limit.

D.1.1 Verify SDM is

≥ 1.6% ∆k/kwithin the limits specified in the COLR.

OR D.1.2 Initiate boration to restore

required SDM to within limit. AND D.2 Be in MODE 3.


SURVEILLANCE REQUIREMENTS

SURVEILLANCE FREQUENCY SR 3.1.5.1 -------------------------------- NOTES ---------------------------------

1. Not required to be performed for rods associated with inoperable rod position indicator or demand position indicator

2. Not required to be performed until 1 hour after

associated rod motion -----------------------------------------------------------------------------

Verify position of individual rods positions within alignment

limit.

12 hours AND Once within 4 hours and every 4 hours thereafter when the rod position deviation monitor is inoperable

SR 3.1.5.2 Verify rod freedom of movement (trippability) by moving

each rod not fully inserted in the core ≥ 10 steps in either direction.

92 days

(continued)



SURVEILLANCE REQUIREMENTS (continued)

SURVEILLANCE FREQUENCY SR 3.1.5.3 Verify rod drop time of each rod, from the fully withdrawn

position, is ≤ 2.7 seconds from the beginning of decay of stationary gripper coil voltage to dashpot entry, with:

a. Tavg ≥ 551°F; and

b. All reactor coolant pumps operating.

Prior to reactor criticality afterinitial fuel loading and each removal of the reactor head

Shutdown Bank Insertion Limits 3.1.6


3.1 REACTIVITY CONTROL SYSTEMS 3.1.6 Shutdown Bank Insertion Limits LCO 3.1.6 Each shutdown bank shall be within insertion limits specified in the COLR.

---------------------------------------------- NOTE --------------------------------------------------- Not applicable to shutdown banks inserted while performing SR 3.1.5.2. -----------------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and, 2

MODE 2 with any control bank not fully inserted.

ACTIONS

CONDITION REQUIRED ACTION COMPLETION TIME A. One or more shutdown

banks not within limitsinserted ≤ 16 steps beyond the insertion limits specified in the COLR.

A.1 Verify all control banks are

within the insertion limits specified in the COLR.

AND A.12.1 Verify SDM is

≥ 1.6% ∆k/kwithin the limits specified in the COLR. OR A.12.2 Initiate boration to

restore SDM to within limit. AND A.23 Restore shutdown banks to

within limitsthe insertion limits specified in the COLR.

1 hour 1 hour 1 hour 2 24 hours

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. One or more shutdown

banks not within limits for reasons other than Condition A.

B.1.1 Verify SDM is within the limits specified in the COLR. OR B.1.2 Initiate boration to restore SDM to within limit. AND B.2 Restore shutdown banks to within limits.


BC. Required Action and

associated Completion Time not met.

BC.1 Be in MODE 3.

6 hours


SURVEILLANCE FREQUENCY

------------------------------------ NOTE ------------------------------------ Not required to be performed until 1 hour after associated rod motion. ----------------------------------------------------------------------------------

SR 3.1.6.1 Verify each shutdown bank is within the insertion limits

specified in the COLR.

12 hours

Control Bank Insertion Limits 3.1.7


3.1 REACTIVITY CONTROL SYSTEMS 3.1.7 Control Bank Insertion Limits LCO 3.1.7 Control banks shall be within the insertion, sequence, and overlap limits


-------------------------------------------------NOTE------------------------------------------------ Not applicable to control banks inserted while performing SR 3.1.5.2. ---------------------------------------------------------------------------------------------------------

APPLICABILITY: MODE 1,

MODE 2 with keff ≥ 1.0.

-------------------------------------------------NOTE------------------------------------------------ This LCO is not applicable while performing SR 3.1.5.2. ---------------------------------------------------------------------------------------------------------

ACTIONS

CONDITION REQUIRED ACTION COMPLETION TIME A. Control bank A, B, or C

inserted ≤ 16 steps beyond the insertion, sequence, or overlap limits specified in the COLR.

A.1 Verify all shutdown banks are within the insertion limits specified in the COLR. AND A.2.1 Verify SDM is within the limits specified in the COLR. OR A.2.2 Initiate boration to restore SDM to within limits. AND A.3 Restore the control bank to within the insertion, sequence, and overlap limits specified in the COLR.

1 hour 1 hour 1 hour 24 hours

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME AB. Control bank insertion limits

not met for reasons other than Condition A.

AB.1.1 Verify SDM is ≥ 1.6% ∆k/k

within the limits specified in the COLR.

OR AB.1.2 Initiate boration to restore

SDM to within limit. AND AB.2 Restore control bank(s) to

within limits.


BC. Control bank sequence or

overlap limits not met for reasons other than Condition A.

BC.1.1 Verify SDM is ≥ 1.6%

∆k/kwithin the limits specified in the COLR.

OR BC.1.2 Initiate boration to restore

SDM to within limit. AND BC.2 Restore control bank

sequence and overlap to within limits.


CD. Required Action and


CD.1 Be in MODE 32 with keff <

1.0.

6 hours




SURVEILLANCE FREQUENCY SR 3.1.7.1 Verify estimated critical control bank position is within

the limits specified in the COLR.

Within 4 hours prior to achieving criticality

SR 3.1.7.2 --------------------------------- NOTE ------------------------------

Not required to be performed until 1 hour after associated rod motion. -------------------------------------------------------------------------

Verify each control bank insertion is within the limits specified in the COLR.

12 hours AND Once within 4 hours and every 4 hours thereafter when the rod insertion limit monitor is inoperable

SR 3.1.7.3 ---------------------------------- NOTE -----------------------------

Not required to be performed until 1 hour after associated rod motion.

-------------------------------------------------------------------------

Verify sequence and overlap limits specified in the COLR are met for control banks not fully withdrawn from the core.

12 hours

Rod Position Indication 3.1.8

Watts Bar-Unit 1 3.1-17 Amendment 58, XX

3.1 REACTIVITY CONTROL SYSTEMS 3.1.8 Rod Position Indication LCO 3.1.8 The Analog Rod Position Indication (ARPI) System and the Demand Position

Indication System shall be OPERABLE.

--------------------------------------------------- NOTE ----------------------------------------------- Individual RPIs are not required to be OPERABLE for 1 hour following movement of the associated rods. ------------------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and 2. ACTIONS --------------------------------------------------------------NOTE--------------------------------------------------------------------- Separate Condition entry is allowed for each inoperable od position indicator per groupRPI and each demand position indicator per bank. -------------------------------------------------------------------------------------------------------------------------------------------

CONDITION REQUIRED ACTION COMPLETION TIME ------------------NOTE------------------- Rod position monitoring by Required Actions A.2.1 and A.2.2 may only be applied to one inoperable ARPI and shall only be allowed: (1) until the end of the current cycle, or (2) until an entry into MODE 5 of sufficient duration, whichever occurs first, when the repair of the inoperable ARPI can safely be performed. Required Actions A.2.1, A.2.2 and A.2.3 shall not be allowed after the plant has been in MODE 5 or other plant condition, for a sufficient period of time, in which the repair of the inoperable ARPI could have safely been performed. ----------------------------------------------

A. One ARPI per group inoperable for in one or more groups.

A.1 Verify the position of the rods

with inoperable position indicatorsRPI indirectly by using either the movable incore detectors or the PDMS.

OR A.2.1 Verify the position of the rods

with the inoperable position indicatorRPI indirectly by using either the movable incore detectors or the PDMS.

AND

Once per 8 hours 8 hours AND Once every 31 days EFPD thereafter AND 8 hours , if rod control system parameters indicateafter discovery of each unintended rod movement

AND

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME A. (continued)

A.2.2 Review the parameters of the

rod control system for indications of unintended rod movement for the rod with an inoperable position indicator.

AND A.2.3 Verify the position of the rod with an inoperable position indicator by using either the movable incore detectors or the PDMS. AND A.2.2 Restore inoperable RPI to

OPERABLE status. OR A.3 Reduce THERMAL POWER to

≤less than or equal to 50% RTP.

16 hours8 hours after each movement of rod with inoperable RPI ˃ 12 steps AND Prior to THERMAL POWER exceeding 50% RTP AND 8 hours after reaching RTP AND Once per 8 hours thereafter 8 hours, if the rod with an inoperable position indicator is moved greater than 12 steps. Prior to entering MODE 2 from MODE 3. AND Prior to increasing THERMAL POWER above 50% RTP and within 8 hours of reaching 100% RTP 8 hours

(continued)


Watts Bar-Unit 1 3.1-18a Amendment 58, XX

ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME

B. More than one RPI per group inoperable in one or more groups.

B.1 Place the control rods under

manual control. AND B.2 Restore inoperable RPIs to

OPERABLE status such that a maximum of one RPI per group is inoperable.

Immediately 24 hours

BC. One or more rods withRPI

inoperable position indicators havein one or more groups and associated rod has been moved ˃in excess of 24 steps in one direction since the last determination of the rod's position.

BC.1 Verify the position of the rods

with inoperable position indicatorsRPIs indirectly by using either the movable incore detectors or the PDMS.

OR BC.2 Reduce THERMAL POWER to


4 hours 8 hours

CD. One or more demand position

indicators per bank inoperable for in one or more banks.

CD.1.1 Verify by administrative means

all ARPIs for the affected banks are OPERABLE.

AND CD.1.2 Verify the most withdrawn rod

and the least withdrawn rod of the affected banks are ≤ 12 less than or equal to 12 steps apart.

OR CD.2 Reduce THERMAL POWER to


Once per 8 hours Once per 8 hours 8 hours

(continued)



ACTIONS (continued) CONDITION REQUIRED ACTION COMPLETION TIME

DE. Required Action and


DE.1 Be in MODE 3.

6 hours


SURVEILLANCE FREQUENCY SR 3.1.8.1 --------------------------------- NOTE ---------------------------

Not required to be met for RPIs associated with rods that do not meet LCO 3.1.5. ----------------------------------------------------------------------

Verify each ARPI agrees within 12 steps of the group

demand position for the full indicated range of rod travel.

18 monthsOnce prior to criticality after each removal of the reactor head.

CNL-16-148 A3-1

ATTACHMENT 3 - PROPOSED TECHNICAL SPECIFICATION CHANGES (MARK-UP) FOR WBN UNIT 2


Watts Bar - Unit 2 3.1-7 Amendment No. XX

3.1 REACTIVITY CONTROL SYSTEMS 3.1.5 Rod Group Alignment Limits LCO 3.1.5 All shutdown and control rods shall be OPERABLE., with all individual

indicated rod positions within 12 steps of their group step counter demand position. AND Individual indicated rod positions shall be within 12 steps of their group step counter demand position.



A. One or more rod(s) untrippableinoperable.

A.1.1 Verify SDM is ≥ 1.6% ∆k/kto be within the limits specified in the COLR.

1 hour

OR

A.1.2 Initiate boration to restore SDM to within limit.

1 hour

AND

A.2 Be in MODE 3. 6 hours


B.1

OR

B.2.1.1B.1.1

Restore rod to within alignment limits.

Verify SDM is ≥ 1.6% ∆k/kto be within the limits specified in the COLR.

1 hour

1 hour

OR OR

B.2.1.2B.1.2

AND

Initiate boration to restore SDM to within limit.

1 hour

(continued)



ACTIONS (continued)


B. (continued) B.2.2 Reduce THERMAL POWER to ≤ 75% RTP.

2 hours

AND

B.2.3 Verify SDM is ≥ 1.6% ∆k/kwithin the limits specified in the COLR.

Once per 12 hours

AND

B.2.4 Perform SR 3.2.1.1, SR 3.2.1.2, and SR 3.2.2.1.

72 hours

AND

B.2.65 Re-evaluate safety analyses and confirm results remain valid for duration of operation under these conditions.

5 days

C. Required Action and associated Completion Time of Condition B not met.

C.1 Be in MODE 3. 6 hours

D. More than one rod not within alignment limit.

D.1.1 Verify SDM is ≥ 1.6% ∆k/kwithin the limits specified in the COLR.

1 hour

OR

D.1.2 Initiate boration to restore required SDM to within limit.

1 hour

AND

D.2 Be in MODE 3. 6 hours





SR 3.1.5.1 ----------------------------- NOTES ------------------------------1. Not required to be performed for rods associated with inoperable rod position indicator or demand position indicator.

2. Not required to be performed until 1 hour after associated rod motion. -----------------------------------------------------------------------

Verify position of individual rods positions within alignment limit.

12 hours

AND

Once within 4 hours and every 4 hours thereafter when the rod position deviation monitor is inoperable

SR 3.1.5.2 Verify rod freedom of movement (trippability) by moving each rod not fully inserted in the core ≥ 10 steps in either direction.

92 days

SR 3.1.5.3 Verify rod drop time of each rod, from the fully withdrawn position, is ≤ 2.7 seconds from the beginning of decay of stationary gripper coil voltage to dashpot entry, with:



Prior to reactor criticality after initial fuel loading and each removal of the reactor head



3.1 REACTIVITY CONTROL SYSTEMS 3.1.6 Shutdown Bank Insertion Limits LCO 3.1.6 Each shutdown bank shall be within insertion limits specified in the COLR. ---------------------------------------------- NOTE -------------------------------------------

Not applicable to shutdown banks inserted while performing SR 3.1.5.2. ---------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and 2,

MODE 2 with any control bank not fully inserted. ACTIONS


A. One or more shutdown bank s not within limitsinserted ≤ 16 steps beyond the insertion limits specified in the COLR.

A.1

AND A.12.1

Verify all control banks are within the insertion limits specified in the COLR.

Verify SDM is ≥ 1.6% ∆k/kwithin the limits specified in the COLR.

1 hour

1 hour

OR


1 hour

AND

A.23 Restore shutdown banks to within limitsthe insertion limits specified in the COLR.

2 24 hours

(continued)



ACTIONS (continued)


B. One or more shutdown banks not within limits for reasons other than Condition A.

B.1.1 Verify SDM is within the limits specified in the COLR.

1 hour

OR

B.1.2 Initiate boration to restore SDM to within limit.

1 hour

AND

B.2 Restore shutdown banks to within limits.

2 hours

B.C. Required Action and associated Completion Time not met.

BC.1 Be in MODE 3. 6 hours



SR 3.1.6.1 -------------------------------- NOTE ----------------------------- Not required to be performed until 1 hour after associated rod motion. -----------------------------------------------------------------------

Verify each shutdown bank is within the insertion limits specified in the COLR

12 hours




specified in the COLR ------------------------------------------ NOTE -----------------------------------------------

Not applicable to control banks inserted while performing SR 3.1.5.2. ---------------------------------------------------------------------------------------------------


MODE 2 with keff ≥ 1.0. ---------------------------------------------NOTE--------------------------------------------

This LCO is not applicable while performing SR 3.1.5.2. -------------------------------------------------------------------------------------------------

ACTIONS


A. Control bank A, B, or C inserted ≤ 16 steps beyond the insertion, sequence, or overlap limits specified in the COLR.

A.1 Verify all shutdown banks are within the insertion limits specified in the COLR.

1 hour

AND

A.2.1 Verify SDM is within the limits specified in the COLR.

1 hour

OR

A.2.2 Initiate boration to restore SDM to within limits.

1 hour

AND

(continued)



ACTIONS (continued)


A. (continued) A.3 Restore the control bank to within the insertion, sequence, and overlap limits specified in the COLR.

24 hours

A. B. Control bank insertion limits not met for reasons other than Condition A.

AB.1.1 Verify SDM is ≥ 1.6% ∆k/kwithin the limits specified in the COLR.

1 hour

OR

AB.1.2 Initiate boration to restore SDM to within limit.

1 hour

AND

AB.2 Restore control bank(s) to within limits.

2 hours

(continued)



ACTIONS (continued)


B. C. Control bank sequence or overlap limits not met for reasons other than Condition A.

BC.1.1 Verify SDM is ≥ 1.6% ∆k/kwithin the limits specified in the COLR.

1 hour

OR

BC.1.2 Initiate boration to restore SDM to within limit.

1 hour

AND

BC.2 Restore control bank sequence and overlap to within limits.

2 hours

C. D. Required Action and associated Completion Time not met

CD.1 Be in MODE 32 with keff < 1.0.

6 hours



SR 3.1.7.1 Verify estimated critical control bank position is within the limits specified in the COLR.


(continued)


Watts Bar - Unit 2 3.1-1514a Amendment No. XX





12 hours

AND

Once within 4 hours and every 4 hours thereafter when the rod insertion limit monitor is inoperable



12 hours


Watts Bar - Unit 2 3.1-15 Amendment XX

3.1 REACTIVITY CONTROL SYSTEMS 3.1.8 Rod Position Indication LCO 3.1.8 The Rod Position Indication (RPI) System and the Demand Position

Indication System shall be OPERABLE. -------------------------------------------- NOTE ---------------------------------------------

Individual RPIs are not required to be OPERABLE for 1 hour following movement of the associated rods. ---------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and 2. ACTIONS -----------------------------------------------------------NOTE------------------------------------------------------------ Separate Condition entry is allowed for each inoperable rod position indicatorRPI per group and each demand position indicator per bank. -------------------------------------------------------------------------------------------------------------------------------


A. One RPI per group inoperable in one or more groups.----------------NOTE----------------- Rod position monitoring by Required Actions A.2.1 and A.2.2 may only be applied to one inoperable RPI and shall only be allowed: (1) until the end of the current cycle, or (2) until an entry into MODE 5 of sufficient duration, whichever occurs first, when the repair of the inoperable RPI can safely be performed. Required Actions A.2.1, A.2.2 and A.2.3 shall not be allowed after the plant has been in MODE 5 or other plant condition, for a sufficient period of time, in which the repair of the inoperable RPI could have safely been performed. -----------------------------------------

A.1 Verify the position of the rods with inoperable position indicatorsRPI indirectly by using the PDMS.

Once per 8 hours

OR

A.2.1 Verify the position of the rods with the inoperable position indicatorRPI indirectly by using the PDMS.

8 hours

AND

Once every 31 days EFPD thereafter

AND

8 hours, if rod control system parameters indicate after discovery of each unintended rod movement

AND

(continued)



ACTIONS (continued)


A. (continued)

A.2.2

OR

A.3

AND

Restore inoperable RPI to OPERABLE status.

Reduce THERMAL POWER to ≤ 50% RTP

8 hours after each movement of rod with inoperable RPI ˃ 12 steps

AND

Prior to THERMAL POWER exceeding 50% RTP

AND

8 hours after reaching RTP

Prior to entering MODE 2 from MODE 3

8 hours


B.1 Place the control rods under manual control.

Immediately

AND

B.2 Restore inoperable RPIs to OPERABLE status such that a maximum of one RPI per group is inoperable.

24 hours

(continued)



ACTIONS (continued)


A. C. One or more rods withRPI inoperable position indicators havein one or more groups and associated rod has been moved ˃in excess of 24 steps in one direction since the last determination of the rod's position.

BC.1 Verify the position of the rods with inoperable position indicatorsRPIs indirectly by using the PDMS.

4 hours

OR

BC.2 Reduce THERMAL POWER to ≤less than or equal to 50% RTP.

8 hours

B. D. One or more demand position indicators per bank inoperable for in one or more banks.

CD.1.1 Verify by administrative means all RPIs for the affected banks are OPERABLE.

Once per 8 hours

AND

CD.1.2 Verify the most withdrawn rod and the least withdrawn rod of the affected banks are ≤ 12 less than or equal to 12 steps apart.

Once per 8 hours

OR

CD.2 Reduce THERMAL POWER to ≤less than or equal to 50% RTP.

8 hours

C. E. Required Action and associated Completion Time not met.

DE.1 Be in MODE 3. 6 hours


Watts Bar - Unit 2 3.1-17a Amendment XX



SR 3.1.8.1 -------------------------------- NOTE ----------------------------- Not required to be met for RPIs associated with rods that do not meet LCO 3.1.5. -----------------------------------------------------------------------

Verify each RPI agrees within 12 steps of the group demand position for the full indicated range of rod travel.

18 monthsOnce prior to criticality after each removal of the reactor head

CNL-16-148 A4-1

ATTACHMENT 4 - REVISED TECHNICAL SPECIFICATION PAGES (FINAL TYPED) FOR WBN UNIT 1



3.1 REACTIVITY CONTROL SYSTEMS 3.1.5 Rod Group Alignment Limits LCO 3.1.5 All shutdown and control rods shall be OPERABLE. AND

Individual indicated rod positions shall be within 12 steps of their group step counter demand position.


CONDITION REQUIRED ACTION COMPLETION TIME A. One or more rod(s) inoperable.

A.1.1 Verify SDM to be within the

limits specified in the COLR. OR A.1.2 Initiate boration to restore

SDM to within limit. AND A.2 Be in MODE 3.



B.1.1 Verify SDM to be within the

limits specified in the COLR. OR B.1.2 Initiate boration to restore

SDM to within limit. AND

1 hour 1 hour

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. (continued)

B.2 Reduce THERMAL

POWER to ≤ 75% RTP. AND B.3 Verify SDM is within the

limits specified in the COLR.

AND B.4 Perform SR 3.2.1.1, SR

3.2.1.2, and SR 3.2.2.1. AND B.5 Re-evaluate safety

analyses and confirm results remain valid for duration of operation under these conditions.

2 hours Once per 12 hours 72 hours 5 days


associated Completion Time of Condition B not met.

C.1 Be in MODE 3.

6 hours

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME D. More than one rod not within

alignment limit.

D.1.1 Verify SDM is within the limits

specified in the COLR. OR D.1.2 Initiate boration to restore

required SDM to within limit. AND D.2 Be in MODE 3.



SURVEILLANCE FREQUENCY SR 3.1.5.1 -------------------------------- NOTES ---------------------------------

1. Not required to be performed for rods associated with inoperable rod position indicator or demand position indicator

2. Not required to be performed until 1 hour after

associated rod motion -----------------------------------------------------------------------------

Verify position of individual rods within alignment limit.

12 hours AND Once within 4 hours and every 4 hours thereafter when the rod position deviation monitor is inoperable

SR 3.1.5.2 Verify rod freedom of movement (trippability) by moving

each rod not fully inserted in the core ≥ 10 steps in either direction.

92 days

(continued)




SURVEILLANCE FREQUENCY SR 3.1.5.3 Verify rod drop time of each rod, from the fully withdrawn

position, is ≤ 2.7 seconds from the beginning of decay of stationary gripper coil voltage to dashpot entry, with:



Prior to criticality after each removal of the reactor head



3.1 REACTIVITY CONTROL SYSTEMS 3.1.6 Shutdown Bank Insertion Limits LCO 3.1.6 Each shutdown bank shall be within insertion limits specified in the COLR.

---------------------------------------------- NOTE --------------------------------------------------- Not applicable to shutdown banks inserted while performing SR 3.1.5.2. -----------------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and 2

ACTIONS

CONDITION REQUIRED ACTION COMPLETION TIME A. One shutdown bank

inserted ≤ 16 steps beyond the insertion limits specified in the COLR.

A.1 Verify all control banks are


AND A.2.1 Verify SDM is within the limits specified in the COLR. OR A.2.2 Initiate boration to restore SDM

to within limit. AND A.3 Restore shutdown bank to



(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. One or more shutdown

banks not within limits for reasons other than Condition A.

B.1.1 Verify SDM is within the limits specified in the COLR. OR B.1.2 Initiate boration to restore SDM to within limit. AND B.2 Restore shutdown banks to within limits.




C.1 Be in MODE 3.

6 hours



------------------------------------ NOTE ------------------------------------ Not required to be performed until 1 hour after associated rod motion. ----------------------------------------------------------------------------------

SR 3.1.6.1 Verify each shutdown bank is within the insertion limits


12 hours





-------------------------------------------------NOTE------------------------------------------------ Not applicable to control banks inserted while performing SR 3.1.5.2. ---------------------------------------------------------------------------------------------------------



ACTIONS

CONDITION REQUIRED ACTION COMPLETION TIME A. Control bank A, B, or C

inserted ≤ 16 steps beyond the insertion, sequence, or overlap limits specified in the COLR.

A.1 Verify all shutdown banks are within the insertion limits specified in the COLR. AND A.2.1 Verify SDM is within the limits specified in the COLR. OR A.2.2 Initiate boration to restore SDM to within limits. AND A.3 Restore the control bank to within the insertion, sequence, and overlap limits specified in the COLR.


(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME B. Control bank insertion limits

not met for reasons other than Condition A.

B.1.1 Verify SDM is within the


OR B.1.2 Initiate boration to restore

SDM to within limit. AND B.2 Restore control bank(s) to

within limits.


C. Control bank sequence or

overlap limits not met for reasons other than Condition A.

C.1.1 Verify SDM is within the


OR C.1.2 Initiate boration to restore

SDM to within limit. AND C.2 Restore control bank

sequence and overlap to within limits.


D. Required Action and


D.1 Be in MODE 2 with keff < 1.0.

6 hours




SURVEILLANCE FREQUENCY SR 3.1.7.1 Verify estimated critical control bank position is within

the limits specified in the COLR.


SR 3.1.7.2 --------------------------------- NOTE ------------------------------

Not required to be performed until 1 hour after associated rod motion. -------------------------------------------------------------------------


12 hours AND Once within 4 hours and every 4 hours thereafter when the rod insertion limit monitor is inoperable

SR 3.1.7.3 ---------------------------------- NOTE -----------------------------

Not required to be performed until 1 hour after associated rod motion.

-------------------------------------------------------------------------


12 hours



3.1 REACTIVITY CONTROL SYSTEMS 3.1.8 Rod Position Indication LCO 3.1.8 The Rod Position Indication (RPI) System and the Demand Position Indication

System shall be OPERABLE.

--------------------------------------------------- NOTE ----------------------------------------------- Individual RPIs are not required to be OPERABLE for 1 hour following movement of the associated rods. ------------------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and 2. ACTIONS --------------------------------------------------------------NOTE--------------------------------------------------------------------- Separate Condition entry is allowed for each inoperable RPI and each demand position indicator. -------------------------------------------------------------------------------------------------------------------------------------------

CONDITION REQUIRED ACTION COMPLETION TIME A. One RPI per group

inoperable in one or more groups.

A.1 Verify the position of the rods

with inoperable RPI indirectly by using either the movable incore detectors or the PDMS.

OR A.2.1 Verify the position of the rods

with the inoperable RPI indirectly by using either the movable incore detectors or the PDMS.

Once per 8 hours 8 hours AND Once every 31 EFPD thereafter AND 8 hours after discovery of each unintended rod movement AND

(continued)



ACTIONS (continued)

CONDITION REQUIRED ACTION COMPLETION TIME A. (continued)

AND A.2.2 Restore inoperable RPI to

OPERABLE status. OR A.3 Reduce THERMAL POWER to

≤ 50% RTP.

8 hours after each movement of rod with inoperable RPI ˃ 12 steps AND Prior to THERMAL POWER exceeding 50% RTP AND 8 hours after reaching RTP Prior to entering MODE 2 from MODE 3. 8 hours

(continued)


Watts Bar-Unit 1 3.1-18a Amendment 58, XX

ACTIONS (continued)



B.1 Place the control rods under

manual control. AND B.2 Restore inoperable RPIs to

OPERABLE status such that a maximum of one RPI per group is inoperable.

Immediately 24 hours

C. One or more RPI inoperable

in one or more groups and associated rod has been moved ˃ 24 steps in one direction since the last determination of the rod's position.

C.1 Verify the position of the rods

with inoperable RPIs indirectly by using either the movable incore detectors or the PDMS.

OR C.2 Reduce THERMAL POWER to

≤ 50% RTP.

4 hours 8 hours

D. One or more demand position

indicators per bank inoperable in one or more banks.

D.1.1 Verify by administrative means

all RPIs for the affected banks are OPERABLE.

AND D.1.2 Verify the most withdrawn rod

and the least withdrawn rod of the affected banks are ≤ 12 steps apart.

OR D.2 Reduce THERMAL POWER to

≤ 50% RTP.

Once per 8 hours Once per 8 hours 8 hours

(continued)



ACTIONS (continued) CONDITION REQUIRED ACTION COMPLETION TIME

E. Required Action and


E.1 Be in MODE 3.

6 hours


SURVEILLANCE FREQUENCY SR 3.1.8.1 --------------------------------- NOTE ---------------------------

Not required to be met for RPIs associated with rods that do not meet LCO 3.1.5. ----------------------------------------------------------------------

Verify each RPI agrees within 12 steps of the group

demand position for the full indicated range of rod travel.

Once prior to criticality after each removal of the reactor head.

CNL-16-148 A5-1

ATTACHMENT 5 - REVISED TECHNICAL SPECIFICATION PAGES (FINAL TYPED) FOR WBN UNIT 2



3.1 REACTIVITY CONTROL SYSTEMS 3.1.5 Rod Group Alignment Limits LCO 3.1.5 All shutdown and control rods shall be OPERABLE.

AND Individual indicated rod positions shall be within 12 steps of their group step counter demand position.



A. One or more rod(s) inoperable.

A.1.1 Verify SDM to be within the limits specified in the COLR.

1 hour

OR


1 hour

AND

A.2 Be in MODE 3. 6 hours


B.1.1 Verify SDM to be within the limits specified in the COLR.

1 hour

OR

B.1.2

AND

Initiate boration to restore SDM to within limit.

1 hour

(continued)



ACTIONS (continued)


B. (continued) B.2 Reduce THERMAL POWER to ≤ 75% RTP.

2 hours

AND

B.3 Verify SDM is within the limits specified in the COLR.

Once per 12 hours

AND

B.4 Perform SR 3.2.1.1, SR 3.2.1.2, and SR 3.2.2.1.

72 hours

AND

B.5 Re-evaluate safety analyses and confirm results remain valid for duration of operation under these conditions.

5 days

C. Required Action and associated Completion Time of Condition B not met.


D. More than one rod not within alignment limit.

D.1.1 Verify SDM is within the limits specified in the COLR.

1 hour

OR

D.1.2 Initiate boration to restore required SDM to within limit.

1 hour

AND

D.2 Be in MODE 3. 6 hours





SR 3.1.5.1 ----------------------------- NOTES ------------------------------1. Not required to be performed for rods associated with inoperable rod position indicator or demand position indicator.

2. Not required to be performed until 1 hour after associated rod motion. -----------------------------------------------------------------------

Verify position of individual rods within alignment limit.

12 hours

AND

Once within 4 hours and every 4 hours thereafter when the rod position deviation monitor is inoperable

SR 3.1.5.2 Verify rod freedom of movement (trippability) by moving each rod not fully inserted in the core ≥ 10 steps in either direction.

92 days

SR 3.1.5.3 Verify rod drop time of each rod, from the fully withdrawn position, is ≤ 2.7 seconds from the beginning of decay of stationary gripper coil voltage to dashpot entry, with:



Prior to criticality after each removal of the reactor head



3.1 REACTIVITY CONTROL SYSTEMS 3.1.6 Shutdown Bank Insertion Limits LCO 3.1.6 Each shutdown bank shall be within insertion limits specified in the COLR. ---------------------------------------------- NOTE -------------------------------------------

Not applicable to shutdown banks inserted while performing SR 3.1.5.2. ---------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and 2

ACTIONS


A. One shutdown bank inserted ≤ 16 steps beyond the insertion limits specified in the COLR.

A.1

AND A.2.1

Verify all control banks are within the insertion limits specified in the COLR.

Verify SDM is within the limits specified in the COLR.

1 hour

1 hour

OR


1 hour

AND

A.3 Restore shutdown bank to within the insertion limits specified in the COLR.

24 hours

(continued)



ACTIONS (continued)


B. One or more shutdown banks not within limits for reasons other than Condition A.


1 hour

OR


1 hour

AND

B.2 Restore shutdown banks to within limits.

2 hours

C. Required Action and associated Completion Time not met.





Verify each shutdown bank is within the insertion limits specified in the COLR

12 hours




specified in the COLR ------------------------------------------ NOTE -----------------------------------------------

Not applicable to control banks inserted while performing SR 3.1.5.2. ---------------------------------------------------------------------------------------------------



ACTIONS


A. Control bank A, B, or C inserted ≤ 16 steps beyond the insertion, sequence, or overlap limits specified in the COLR.

A.1 Verify all shutdown banks are within the insertion limits specified in the COLR.

1 hour

AND

A.2.1 Verify SDM is within the limits specified in the COLR.

1 hour

OR

A.2.2 Initiate boration to restore SDM to within limits.

1 hour

AND

(continued)



ACTIONS (continued)


A. (continued) A.3 Restore the control bank to within the insertion, sequence, and overlap limits specified in the COLR.

24 hours

B. Control bank insertion limits not met for reasons other than Condition A.


1 hour

OR


1 hour

AND

B.2 Restore control bank(s) to within limits.

2 hours

(continued)



ACTIONS (continued)


C. Control bank sequence or overlap limits not met for reasons other than Condition A.

C.1.1 Verify SDM is within the limits specified in the COLR.

1 hour

OR

C.1.2 Initiate boration to restore SDM to within limit.

1 hour

AND

C.2 Restore control bank sequence and overlap to within limits.

2 hours

D. Required Action and associated Completion Time not met.

D.1 Be in MODE 2 with keff < 1.0.

6 hours



SR 3.1.7.1 Verify estimated critical control bank position is within the limits specified in the COLR.


(continued)


Watts Bar - Unit 2 3.1-14a Amendment No. XX





12 hours

AND

Once within 4 hours and every 4 hours thereafter when the rod insertion limit monitor is inoperable



12 hours



3.1 REACTIVITY CONTROL SYSTEMS 3.1.8 Rod Position Indication LCO 3.1.8 The Rod Position Indication (RPI) System and the Demand Position

Indication System shall be OPERABLE. -------------------------------------------- NOTE ---------------------------------------------

Individual RPIs are not required to be OPERABLE for 1 hour following movement of the associated rods. ---------------------------------------------------------------------------------------------------

APPLICABILITY: MODES 1 and 2. ACTIONS -----------------------------------------------------------NOTE------------------------------------------------------------ Separate Condition entry is allowed for each inoperable RPI and each demand position indicator. -------------------------------------------------------------------------------------------------------------------------------


A. One RPI per group inoperable in one or more groups.

A.1 Verify the position of the rods with inoperable RPI indirectly by using the PDMS.

Once per 8 hours

OR

A.2.1 Verify the position of the rods with the inoperable RPI indirectly by using the PDMS.

8 hours

AND

Once every 31 EFPD thereafter

AND

8 hours after discovery of each unintended rod movement

AND

(continued)



ACTIONS (continued)


A. (continued)

A.2.2

OR

A.3

AND

Restore inoperable RPI to OPERABLE status.

Reduce THERMAL POWER to ≤ 50% RTP

8 hours after each movement of rod with inoperable RPI ˃ 12 steps

AND

Prior to THERMAL POWER exceeding 50% RTP

AND

8 hours after reaching RTP

Prior to entering MODE 2 from MODE 3

8 hours


B.1 Place the control rods under manual control.

Immediately

AND

B.2 Restore inoperable RPIs to OPERABLE status such that a maximum of one RPI per group is inoperable.

24 hours

(continued)



ACTIONS (continued)


C. One or more RPI inoperable in one or more groups and associated rod has been moved ˃ 24 steps in one direction since the last determination of the rod's position.

C.1 Verify the position of the rods with inoperable RPIs indirectly by using the PDMS.

4 hours

OR

C.2 Reduce THERMAL POWER to ≤ 50% RTP.

8 hours

D. One or more demand position indicators per bank inoperable in one or more banks.

D.1.1 Verify by administrative means all RPIs for the affected banks are OPERABLE.

Once per 8 hours

AND

D.1.2 Verify the most withdrawn rod and the least withdrawn rod of the affected banks are ≤ 12 steps apart.

Once per 8 hours

OR

D.2 Reduce THERMAL POWER to ≤ 50% RTP.

8 hours

E. Required Action and associated Completion Time not met.

E.1 Be in MODE 3. 6 hours


Watts Bar - Unit 2 3.1-17a Amendment XX



SR 3.1.8.1 -------------------------------- NOTE ----------------------------- Not required to be met for RPIs associated with rods that do not meet LCO 3.1.5. -----------------------------------------------------------------------

Verify each RPI agrees within 12 steps of the group demand position for the full indicated range of rod travel.

Once prior to criticality after each removal of the reactor head

CNL-16-148 A6-1

ATTACHMENT 6 - PROPOSED TECHNICAL SPECIFICATION BASES CHANGES (MARK-UP) FOR WBN UNIT 1 (FOR INFORMATION ONLY)

Rod Group Alignment Limits B 3.1.5

(continued)

Watts Bar-Unit 1 B 3.1-24 Revision 51, XX

B 3.1 REACTIVITY CONTROL SYSTEMS B 3.1.5 Rod Group Alignment Limits BASES BACKGROUND The OPERABILITY (ei.ge., trippability) of the shutdown and control rods is an

initial assumption in all safety analyses that assume rod insertion upon reactor trip. Maximum rod misalignment is an initial assumption in the safety analysis that directly affects core power distributions and assumptions of available SDM.

The applicable criteria for these reactivity and power distribution design

requirements are 10 CFR 50, Appendix A, GDC 10, "Reactor Design," and GDC 26, "Reactivity Control System Redundancy and Capability," (Ref. 1), and 10 CFR 50.46, "Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Reactors" (Ref. 2).

Mechanical or electrical failures may cause a control or shutdown rod to become

inoperable or to become misaligned from its group. Control rod Rod inoperability or misalignment may cause increased power peaking, due to the asymmetric reactivity distribution and a reduction in the total available rod worth for reactor shutdown. Therefore, control rod alignment and OPERABILITY are related to core operation in design power peaking limits and the core design requirement of a minimum SDM.

Limits on control rod alignment have been established, and all rod positions are

monitored and controlled during power operation to ensure that the power distribution and reactivity limits defined by the design power peaking and SDM limits are preserved.

Rod cluster control assemblies (RCCAs), or rods, are moved by their control rod

drive mechanisms (CRDMs). Each CRDM moves its RCCA one step (approximately 5/8 inch) at a time, but at varying rates (steps per minute) depending on the signal output from the Rod Control System.

The RCCAs are divided among control banks and shutdown banks. Each bank

may be further subdivided into two groups to provide for precise reactivity control (Shutdown Banks C and D have only one group each). A group consists


BASES

(continued)

Watts Bar-Unit 1 B 3.1-25 Revision 51, XX

BACKGROUND of two or more RCCAs that are electrically paralleled to step simultaneously. (continued) Except for Shutdown Banks C and D, a bank of RCCAs consists of two groups

that are moved in a staggered fashion, but always within one step of each other. There are four control banks and four shutdown banks.

The shutdown banks are maintained either in the fully inserted or fully withdrawn

position. The control banks are moved in an overlap pattern, using the following withdrawal sequence: When control bank A reaches a predetermined height in the core, control bank B begins to move out with control bank A. Control bank A stops at the position of maximum withdrawal, and control bank B continues to move out. When control bank B reaches a predetermined height, control bank C begins to move out with control bank B. This sequence continues until control banks A, B, and C are at the fully withdrawn position, and control bank D is approximately halfway withdrawn. The insertion sequence is the opposite of the withdrawal sequence. The control rods are arranged in a radially symmetric pattern, so that control bank motion does not introduce radial asymmetries in the core power distributions.

The axial position of shutdown rods and control rods is indicated by two separate

and independent systems, which are the Bank Demand Position Indication System (commonly called group step counters) and the Analog Rod Position Indication (ARPI) System.

The Bank Demand Position Indication System counts the pulses from the rod

control system that moves the rods. There is one step counter for each group of rods. Individual rods in a group all receive the same signal to move and should, therefore, all be at the same position indicated by the group step counter for that group. The Bank Demand Position Indication System is considered highly precise (± 1 step or ± 5/8 inch). If a rod does not move one step for each demand pulse, the step counter will still count the pulse and incorrectly reflect the position of the rod.

The ARPI System provides an accurate indication of actual control rod position,

but at a lower precision than the step counters. This system is based on inductive analog signals from a series of coils spaced along a hollow tube with a center to center distance of 3.75 inches, which is six steps. The normal


BASES

(continued)

Watts Bar-Unit 1 B 3.1-26 Revision XX

BACKGROUND indication accuracy of the ARPI System is ±+ 6 steps (±+ 3.75 inches), (continued) and the maximum uncertainty is ±+ 12 steps (±+ 7.5 inches). With an indicated

deviation of 12 steps between the group step counter and ARPI, the maximum deviation between actual rod position and the demand position could be 24 steps, or 15 inches.

APPLICABLE Control rod misalignment accidents are analyzed in the safety analysis SAFETY ANALYSES (Ref. 3). The acceptance criteria for addressing control rod inoperability or

misalignment are that: a. There be no violations of: 1. specified Specified acceptable fuel design limits, or 2. Reactor Coolant System (RCS) pressure boundary integrity; and b. The core remains subcritical after accident transients other than a main

steam line break (MSLB). Two types of misalignment are distinguished. During movement of a control rod

group, one rod may stop moving, while the other rods in the group continue. This condition may cause excessive power peaking. The second type of misalignment occurs if one rod fails to insert upon a reactor trip and remains stuck fully withdrawn. This condition requires an evaluation to determine that sufficient reactivity worth is held in the control rods to meet the SDM requirement, with the maximum worth rod stuck fully withdrawn.

Three types of analysis are performed in regard to static rod misalignment

(Ref. 4). The first type of analysis considers the case where any one rod is completely inserted into the core with all other rods completely withdrawn. With control banks at their insertion limits, the second type of analysis considers the case when any one rod is completely inserted into the core. The third type of analysis considers the case of a completely withdrawn single rod from a bank inserted to its insertion limit. Satisfying limits on departure from nucleate boiling ratio in both of these cases bounds the situation when a rod is misaligned from its group by 12 steps.


BASES

(continued)

Watts Bar-Unit 1 B 3.1-27 Revision 104, XX Amendment 82, XX

APPLICABLE Another type of misalignment occurs if one RCCA fails to insert upon a SAFETY ANALYSES reactor trip in response to a main steam pipe rupture and remains stuck (continued) fully withdrawn. This condition is assumed in the evaluation to determine that the required SDM is met with the maximum worth RCCA also fully withdrawn

(Ref. 5). The reactor is shutdown by the boric acid injection delivered by the ECCS.

The Required Actions in this LCO ensure that either deviations from the

alignment limits will be corrected or that THERMAL POWER will be adjusted so that excessive local linear heat rates (LHRs) will not occur, and that the requirements on SDM and ejected rod worth are preserved.

Continued operation of the reactor with a misaligned control rod is allowed if the

heat flux hot channel factor (FQ(Z)) and the nuclear enthalpy hot channel factor(FN∆H) are verified to be within their limits in the COLR and the safety analysis is verified to remain valid. When a control rod is misaligned, the assumptions that are used to determine the rod insertion limits, AFD limits, and quadrant power tilt limits are not preserved. Therefore, the limits may not preserve the design peaking factors, and FQ(Z) and FN∆H must be verified directly using incore power distribution measurements. Bases Section 3.2 (Power Distribution Limits) contains more complete discussions of the relation of FQ(Z) and FN∆H to the operating limits.

Shutdown and control rod OPERABILITY and alignment are directly related to

power distributions and SDM, which are initial conditions assumed in safety analyses. Therefore they satisfy Criterion 2 of 10 CFR 50.36(c)(2)(ii)the NRC Policy Statement.

LCO The limits on shutdown or control rod alignments ensure that the assumptions in

the safety analysis will remain valid. The requirements on OPERABILITY ensure that upon reactor trip, the assumed reactivity will be available and will be inserted. The control rod OPERABILITY requirements (i.e., trippability) also are acceptable from the alignment requirements, which ensure that the RCCAs and banks maintain the correct power distribution and rod alignment. The rod OPERABILITY requirement is satisfied provided the rod will fully insert in the required rod drop time assumed in the safety analysis. Rod control malfunctions that do not result in the inability to move a rod (e.g., rod lift coil failures), but that do not impact trippability, do not result in rod inoperability.

The requirement to maintain the rod alignment to within plus or minus 12 steps is

conservative. The minimum misalignment assumed in safety analysis is 24 steps (15 inches), and in some cases a total misalignment from fully withdrawn to fully inserted is assumed.


BASES

(continued)

Watts Bar-Unit 1 B 3.1-28 Revision XX

LCO Failure to meet the requirements of this LCO may produce unacceptable power (continued) peaking factors and LHRs, or unacceptable SDMs, all of which may constitute initial conditions inconsistent with the safety analysis. APPLICABILITY The requirements on RCCA OPERABILITY and alignment are applicable in

MODES 1 and 2 because these are the only MODES in which neutron (or fission) power is generated, and the OPERABILITY (i.e., trippability) and alignment of rods have the potential to affect the safety of the plant. In MODES 3, 4, 5, and 6, the alignment limi

Watts Bar, Units 1 and 2 - Application to Revise Technical ...Tennessee Valley Authority, 1101...

Documents

Transcript of Watts Bar, Units 1 and 2 - Application to Revise Technical ...Tennessee Valley Authority, 1101...