L-2007-175, Rod Position Indication Systems

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Rod Position Indication Systems
ML073241002
Person / Time
Site: Turkey Point  NextEra Energy icon.png
Issue date: 11/12/2007
From: Jefferson W
Florida Power & Light Co
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
L-2007-175, LAR 194, TAC MD2514, TAC MD2515
Download: ML073241002 (21)
v • d • e


Text

November 12, 2007 L-2007-175

  • FP 10 CFR 50.90 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 RE: Turkey Point Units 3 and 4 Docket Nos. 50-250 and 50-251 License Amendment Request - LAR 194 Rod Position Indication Systems Referencel: FPL letter L-2002-152, "Turkey Point Unit 4 Docket No. 50-251, Proposed License Amendment Inoperable Rod Position Indication, "dated July 29, 2002.

Reference 2: FPL letter L-2004-174,, "Turkey Point Unit 4 Docket No. 50-251, Proposed License Amendment Inoperable Rod Position Indication, "dated July 28, 2004.

Reference 3: FPL letter L-2006-209, "Turkey Point Unit 3 Docket No. 50-250, Proposed License Amendment Inoperable Rod Position Indication, "dated September 8, 2006.

Pursuant to 10 CFR 50.90, Florida Power and Light Company (FPL) requests expedited approval of changes to the Turkey Point Units 3 and 4 Facility Renewed Operating Licenses DPR-31 and DPR-41, respectively, by incorporating the attached Technical Specification (TS) revision. The proposed amendment would revise Technical Specification 3.1.3.2 to allow use of an alternate method of monitoring rod position for a control rod or shutdown rod with an inoperable rod position indicator (RPI). The proposed alternate method of monitoring the stationary gripper coil voltage has been previously submitted by FPL per references 1, 2 and 3, and approved by the NRC for use at Turkey Point Units 3 and 4. The most recent NRC approval of the alternate method for monitoring rod position was approved on October 5, 2006, by issuance of License Amendment 230 for Turkey Point Unit 3 for control rod M-6 in Control Rod Bank C during Cycle 22 operation. FPL's previous submittals were temporary in nature and specifically applicable to the unit with the inoperable RPI.

Additionally use of the alternate method of monitoring rod position was limited to the specific rod with the inoperable RPI for operation for the remainder of the specific operating cycle.

Turkey Point has experienced several failures of the Turkey Point Units 3 and 4 Analog RPI system as documented in References 1, 2 and 3. The proposed amendment will revise Technical Specification 3.1.3.2 on a permanent basis to allow use of an alternate method of monitoring rod position for a control rod or shutdown rod with an inoperable RPI. This submittal is similar to the Sequoyah Nuclear Plant Units 1 and 2 Technical Specification Change 06-04, "Monitoring of Control or Shutdown Rod Position by an Alternate Means," submitted to the NRC July 6, 2006 and approved by the NRC on December 11, 2006 (TAC Nos. MD2514 and MD2515). The method to be used will monitor the stationary gripper coil of the Control Rod Drive Mechanism (CRDM) for the control or shutdown rod with an inoperable analog RPI. The amendment will provide a less burdensome monitoring method than currently required by TS 3.1.3.2 when problems with the analog RPI system are experienced.

When a problem in the RPI system requires the monitoring of a rod's position by the alternate means, FPL intends to continue operation until the end of the current cycle, or until an entry into Mode 3 when the inoperable RPI will be repaired.

an FPL Group company

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Page 2 of 3 License Amendment Request -LAR 194 Rod Position Indication Systems FPL is requesting expedited review of this amendment due to the unanticipated failure of the Turkey Point Unit 3 Analog RPI for control rod F-2 in Control Rod Bank B. The failure of the Unit 3 RPI for control rod F-2 in Control Rod Bank B has resulted in a loss of position indication for that rod.

Control Rod Bank B, including control rod F-2, is currently in the all rods out position. This was confirmed by movable incore detectors. Troubleshooting activities outside containment have indicated a low resistance between the primary conductor to ground and to the secondary conductor. Specialty equipment was used to further identify the fault inside containment near the reactor head. Accessibility and significant radiation dose prevent repairs during power operation.

The connection to the coil stack needs inspection and repair during an outage. FPL plans to continue unit operation until Unit 3 enters Mode 3 when the inoperable RPI will be repaired. The RPI will be repaired no later than the Unit 3 Cycle 24 refueling outage in Spring 2009.

With one analog RPI per bank inoperable, TS 3.1.3.2.a action statement currently requires to either:

1.) Determine the position of the non-indicating rod(s) indirectly by the movable incore detectors at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and within one hour after any motion of the non-indicating rod which exceeds 24 steps in one direction since the last determination of the rod's position, or 2.) Reduce THERMAL POWER to less than 75% of RATED THERMAL POWER within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

FPL is currently implementing TS 3.1.3.2.a action statement. As a result, there is a concern regarding excessive wear of the movable incore detector system, due to exercising the movable incore detectors every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> (approximately 90 times per month), to comply with the compensatory actions required by the current action statement. Although, wear of the incore detector system does not pose a reduction in the margin of safety, excessive wear of the incore detector system could result in a loss of functionality of the system. This could lead to the inability to complete required surveillances, which if not completed could lead to a required plant power reduction and/or shutdown.

The proposed changes have been evaluated in accordance with 10CFR50.91(a)(1), using the criteria in 10CFR50.92(c). FPL has determined that the proposed changes involve no significant hazards considerations. A description of the proposed changes is included in Attachment 1 to this letter. Attachment 2 is the "Determination of No Significant Hazards Consideration." Attachments 3 and 4 contain copies of the affected Technical Specifications pages marked-up and a clean copy of the proposed revision, respectively.

The Turkey Point Plant Nuclear Safety Review Committee and the FPL Company Nuclear Review Board have reviewed the proposed amendment. Upon approval of the proposed changes, FPL requests that the amendments be made effective on the date of issuance.

In accordance with 10 CFR 50.91(b)(1), a copy of the proposed amendment is being forwarded to the State Designee for the State of Florida.

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Page 3 of 3 License Amendment Request -LAR 194 Rod Position Indication Systems Please contact Paul Infanger, Licensing Manager, at (305) 246-6632, if there are any questions regarding this submittal.

I declare under penalty of perjury that the foregoing is true and correct.

Very truly yours,

/ 2 7 Executed 6n Vice President Turkey Point Nuclear Plant Attachments cc: Regional Administrator, Region II, USNRC Senior Resident Inspector, USNRC, Turkey Point Plant Mr. W. A. Passetti, Florida Department of Health

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 1 of 9 Rod Position Indication Systems EVALUATION OF PROPOSED TS CHANGE

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 2 of 9 Rod Position Indication Systems EVALUATION OF PROPOSED TS CHANGES BACKGROUND Turkey Point has experienced several failures of the Turkey Point Units 3 and 4 Analog Rod Position Indication (RPI) system as documented in References 1, 2 and 3. Turkey Point Unit 3 is currently operating with a failed Analog RPI for control rod F-2 in Control Rod Bank B. The failure of the Unit 3 RPI for control rod F-2 in Control Rod Bank B has resulted in a loss of position indication for that rod. Control Rod Bank B, including rod F-2, is currently in the all rods out position. This was confirmed by movable incore detectors. Attempts to repair the RPI for control rod F-2 have been unsuccessful. Troubleshooting activities outside containment have indicated a low resistance between the primary conductor to ground and the secondary conductor. Specialty equipment was used to further identify the fault inside containment near the reactor head.

All of the RPIs were tested on October 7, 2007, during the recent Unit 3 refueling outage. All of the RPIs, including the now failed F-2 RPI, tested satisfactorily. Shortly after that time, on October 16, 2007, RPI F-2 failed due to a short from the primary coil to ground. The suspected cause of this ground is mechanical damage due to inadvertent contact during outage activities on the reactor vessel head after the October 7, 2007 testing. The F-2 RPI is located on the periphery of the core near an access port and was susceptible to external physical contact during certain activities that were performed during the subject time period. Thirty-seven RPIs (Control Rod Banks A, C and D, and Shutdown Rod Banks A, and B) were tested on October 28, 2007, and November 1, 2007, to confirm that other RPIs were not experiencing degradation. Two of the 37 RPIs tested are in close proximity to the F-2 RPI. All 37 RPIs tested satisfactorily.

Accessibility and significant radiation dose prevent repairs during power. The connection to the coil stack needs inspection and repair during an outage. Repairs will be performed at the earliest opportunity, when Turkey Point Unit 3 enters Mode 3, but no later than Unit 3 Cycle 24 refueling outage in Spring 2009.

Current Technical Specification TS 3.1.3.2, Position Indication Systems - Operating, defines the Limiting Condition for Operation for the Analog RPI system. With one analog RPI per bank inoperable, TS 3.1.3.2.a action statement currently requires that 1.) Determine the position of the non-indicating rod(s) indirectly by the movable incore detectors at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and within one hour after any motion of the non-indicating rod which exceeds 24 steps in one direction since the last determination of the rod's position, or 2.) Reduce THERMAL POWER to less than 75% of RATED THERMAL POWER within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

FPL is currently implementing TS 3.1.3.2.a.1 action statement due to a failed RPI in Unit 3 for control rod F-2 in Control Rod Bank B.

There is a concern regarding excessive wear of the movable incore detector system, due to exercising the movable incore detectors every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> (approximately 90 times per month), to comply with the compensatory actions required by the current action statement TS 3.1.3.2.a.1 Although, wear of the incore detector system does not pose a reduction in the margin of safety, excessive wear of the incore detector system could result in a loss system functionality. This could lead to the inability to complete

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 3 of 9 Rod Position Indication Systems required surveillances, which if not completed could lead to a required plant power reduction and/or shutdown.

DESCRIPTION OF PROPOSED LICENSE AMENDMENTS Pursuant to 10 CFR 50.90, FPL requests that Turkey Point Units 3 and 4 Technical Specification (TS) 3.1.3.2, be modified on a permanent basis to allow the use of an alternate method of determining rod position for a control rod or shutdown rod with an inoperable RPI. The proposed alternate method of monitoring the stationary gripper coil voltage has been previously submitted by FPL per references 1, 2 and 3, and approved by the NRC for use at Turkey Point Units 3 and 4. The NRC approved the alternate method for monitoring rod position on October 5, 2006, by issuance of License Amendment 230 for Turkey Point Unit 3 for control rod M-6 in Control Rod Bank C during Cycle 22 operation. FPL's previous submittals were temporary in nature and specifically applicable to the unit with the inoperable RPI. Additionally use of the alternate method of monitoring rod position was limited to the specific rod with the inoperable RPI for operation for the remainder of the specific operating cycle.

FPL is requesting expedited review of this amendment due to the unanticipated failure of the Turkey Point Unit 3 Analog RPI for control rod F-2 in Control Rod Bank B. The proposed amendment will revise Technical Specification 3.1.3.2 on a permanent basis to allow use of an alternate method of monitoring rod position for a control rod or shutdown rod with an inoperable RPI. This request is similar to the Sequoyah Nuclear Plant Units 1 and 2 Technical Specification Change 06-04, "Monitoring of Control or Shutdown Rod Position by an Alternate Means," submitted to the NRC July 6, 2006 and approved by the NRC on December 11, 2006 (TAC Nos. MD2514 and MD2515).

The proposed changes to TS 3.1.3.2 will add a new action that allows use of an alternate method for determining rod position. Action a.2.a), a.2.b), and a.2.c) will be incorporated to provide for the alternative monitoring. The new requirements are as follows:

2** a). Determine the position of the non-indicating rod indirectly by the movable incore detectors within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and once every 31 Effective Full Power Days thereafter, and within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> if rod control system parameters indicate unintended movement, or if the rod with an inoperable position indicator is moved greater than 12 steps, and b). Review the parameters of the rod control system for indications of unintended rod movement for the rod with an inoperable indicator within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and c). Determine the position of the non-indicating rod indirectly by the movable incore detectors prior to increasing THERMAL POWER above 50% RATED THERMAL POWER and within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of reaching 100% RATED THERMAL POWER, or In order to maintain proper numbering considering the addition of a new TS 3.1.3.2 Action a.2, the numbering of current TS 3.1.3.2 Action a.2. will be revised to be Action a.3.

A footnote is added that will apply to the new Action a.2. This footnote describes the limitations for the use of these new provisions. The new footnote reads as follows:

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 4 of 9 Rod Position Indication Systems

    • Rod position monitoring by Actions a.2.a), a.2.b), and a.2.c) may only be applied to one inoperable rod position indicator per unit and shall only be allowed until an entry into MODE 3.

In summary, the proposed change will add new requirements to allow alternate monitoring of the rod position when the analog RPI is not operable. This allowance can only be used for one rod indication per unit and can only be used until the next opportunity to safely correct the problem. The alternate method of monitoring rod position provides reasonable indication of rod position without subjecting the movable incore detectors to excessive wear.

JUSTIFICATION FOR PROPOSED TS CHANGE As described in the bases for Specification 3.1.3, the purpose of the rod control system, of which the RPIs are an integral part, is to ensure that: "(1) acceptable power distribution limits are maintained, (2) the minimum SHUTDOWN MARGIN is maintained, and (3) the potential effects of rod misalignment on associated accident analyses are limited. OPERABILITY of the control rod position indicators is required to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits."

FPL has determined that these objectives can be met with an inoperable RPI in a control rod bank or shutdown bank without subjecting the movable incore system to unnecessary additional wear.

FPL will provide a display to track parameters of the stationary gripper coil of the Control Rod Drive Mechanism (CRDM) on the non-indicating rod. In accordance with proposed Action a.2.a), FPL will determine the position of the non-indicating rod indirectly by the movable incore detectors within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. Additionally, proposed Action a.2.a) will require confirmation of the position for the non-indicating control rod or shutdown rod at least once every 31 Effective Full Power Days using the movable incore system. Proposed Action a.2.b) will require verification that the coil has not changed state at least once every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. This 8-hour surveillance period is consistent with the current operational requirements of control rod position determination using the movable incore detectors and is more frequent than the normal 12-hour requirement for position determination specified in TS 4.1.3.1.1. If the coil has changed state, a determination of the position for the non-indicating control rod or shutdown rod will be made within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> by using the movable incore detector system as required by proposed Action a.2.a). If the rod with the inoperable position indicator is moved greater than 12 steps, proposed Action a.2.a) will determine the position of the non-indicating rod indirectly by the movable incore detectors within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. This provision provides assurance that any unintended rod movement is identified in a timely manner. Proposed Action a.2.c) requires the use of the movable incore detector system to verify rod position prior to increasing thermal power above 50 percent rated thermal power (RTP) and within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of reaching 100 percent RTP. These provisions are intended to establish and confirm the position of the rod with the inoperable RPI to ensure that power distribution requirements are not violated.

In summary, FPL concludes that the proposed change will continue to ensure that the intent of Technical Specifications are met.

In evaluating the requested change, the following conditions were considered:

  • Rod Drop or Rod Misalignment During Power Operation
  • Rod Drop or Rod Misalignment During Reactor Startup

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 5 of 9 Rod Position Indication Systems Rod Drop or Rod Misalignment During Power Operation A full rod drop of a control rod or shutdown rod would be immediately detectable by other means than the position indication system. Independent indication of a dropped control rod is obtained by using the excore power range signals. This rod drop detection circuit is actuated upon sensing a rapid decrease in flux and is designed such that normal load variations do not cause it to be actuated. Furthermore, a negative reactivity insertion corresponding to the reactivity worth of a full rod drop would cause a noticeable change in core parameters including core power and core average temperature.

A rod misalignment of a control rod may also be detectable by other means, e.g. axial flux deviation and the required operator actions would therefore not be dependent on the status of the individual rod position indication system. During normal operation, all control rods operate at the all rods out position of 228 to 230 steps as defined in the Core Operating Limits Report (COLR).

For the infrequent instances when control rod bank movement is required during power operation a determination of the rod position will be made by using the movable incore detector system in accordance with plant procedures.

With alternate CRDM parameter monitoring and rod drop/misalignment parameter indications, the increase in the likelihood of an undetected rod drop or misalignment is considered to be negligible.

Rod Drop or Rod Misalignment During Reactor Startup Repairs will be performed at the earliest opportunity when the unit enters Mode 3, but no later than the next refueling outage.

Reactor Trip Following a reactor trip, the position indication system is used to verify that all rods have fully inserted. Current plant procedures require emergency boration if more than one rod fails to fully insert. The inoperability of the position indication system prevents verification of insertion for the subject rod during reactor trip. As an additional conservative measure administrative controls will be used to heighten reactor operator awareness when the rod position indication for a control rod or shutdown bank is inoperable. This will ensure that emergency boration is initiated, as required by existing procedures, if another rod other than the rod with an inoperable RPI does not fully insert. Turkey Point typically performs a manual reactor trip from approximately 25% power in the event of a controlled shutdown so that these post-trip procedures would also be used.

Shutdown Margin Consistent with TS 3/4.1.1.1, SHUTDOWN MARGIN in Modes 1 and 2 is ensured by verifying compliance with the control rod bank insertion limits of TS 3.1.3.6. The surveillance specified in TS 4.1.3.6 is performed with the Rod Insertion Limit Monitor, which relies on the group step counter demand position indication and is unaffected by an inoperable Analog RPI for a control rod.

Nevertheless, in the case when the Rod Insertion Limit Monitor is inoperable, the analog RPI for individual rods can be used to demonstrate compliance with TS 3.1.3.6 consistent with TS surveillance requirement 4.1.3.6. The proposed alternate method to monitor the stationary gripper coil for a control rod with an inoperable RPI will provide assurance that the position has not

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 6 of 9 Rod Position Indication Systems changed and remains within the allowed misalignment with the group step counter demand position for the affected control rod and the control rod bank insertion limits of TS 3.1.3.6.

In addition, verification of compliance with required SHUTDOWN MARGIN in Modes 1 and 2 also relies upon the rods being movable and trippable. This is verified by periodic rod exercise consistent with TS surveillance requirement 4.1.3.1.2. During the performance of this rod exercise procedure, the affected rod will be exercised and flux traces will be performed after insertion and removal to confirm the position of the rod with the inoperable RPI. Thus, the moveable and trippable status of the affected rod will be confirmed and the affected rod can continue to be credited in verification of SHUTDOWN MARGIN in Modes 1 and 2.

Consistent with TS 3/4.1.1.1 and TS 3/4.1.1.2, SHUTDOWN MARGIN in Modes 3, 4 and 5 is ensured by considering Reactor Coolant System (RCS) boron concentration, rod position, RCS average temperature, fuel burnup, xenon concentration and samarium concentration. Plant procedures ensure SHUTDOWN MARGIN in Modes 3, 4 and 5 by specifying RCS boron concentration requirements that consider all these factors. While in Modes 3, 4 and 5 the analog rod position indication is relied upon to determine rod position. While the analog RPI for a rod remains out-of-service in Modes 3, 4 and 5, rod position cannot be easily determined. Accordingly, these RCS boron concentration requirements will be increased to consider an allowance for the withdrawn worth of a control rod with an inoperable RPI assuming this control rod has the highest reactivity allowance. Shutdown Margin Calculation with two or more rods stuck will conservatively bound a boron concentration to satisfy Shutdown Margin requirements. Shutdown Margin Calculation procedure 0-OP-028.2 will be revised to ensure that shutdown margin limits continue to be met for the remainder of this operating cycle. The use of the alternate methodology requires that the pertinent procedures are modified to account for the rod with the inoperable RPI.

Thus, the proposed alternate position verification for a control or shutdown rod with an inoperable RPI while at power, the normal rod exercise surveillance of control rods and the increased shutdown boron concentration requirements will ensure compliance with the SHUTDOWN MARGIN requirements of TS 3.1.1.1 and TS 3.1.1.2 will be maintained.

Proposed Alternate Rod Position Monitoring Method Implementation Parameter Monitored For the present time, the parameter monitored for a control rod or shutdown rod with an inoperable RPI will be the stationary gripper coil current. The control rods are held in place by energized stationary gripper coils. The control rod can not be moved without de-energizing the stationary gripper coil. The rod control power cabinet design uses a resistor to monitor the coil current. The gripper coil current (measured as an equivalent voltage) will be monitored on an existing control room recorder mounted on a vertical panel within the control room surveillance area. This recorder is a multi-channel recorder with currently one channel in continuous use for Generator Gross Mega-Watts. A spare channel will be used to display the gripper current for a control rod or shutdown rod with an inoperable RPI. Typically, the normal gripper current is 4.4 amps, which when measured across the resistor will be equivalent to 275 milli-volts. The recorder has alarm indication in a form of a display window, which is programmed for a low and high voltage alarm indicative of a gripper coil change of state. Additionally, the gripper coil low and high voltage alarm will provide an output to a control room annunciator window to indicate a potential rod unintended movement based on a low or high voltage, indicative of a gripper coil change of state.

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 7 of 9 Rod Position Indication Systems Operator Traininq The licensed Reactor and Senior Reactor Operators will be responsible for monitoring the output data from the alternate monitoring equipment. The display instrument will be programmed to display CRDM parameter trends and numerical values for rod with the inoperable RPI. Operating procedure 3/4-OSP-201.1 " RCO Daily Log", will provide instructions for monitoring CRDM parameter trends. Accordingly, the indicated value for the rod with the inoperable RPI will be logged by the Operators at least every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />. The Operators will be able to identify any changes in gripper coil state based on a deviation from the normal state, which is defined by a predetermined operating band as well as by a programmed alarm, and by observing the historical trend line displayed. Additionally, a rod trouble annunciator will be added to provide an audible alarm indicating a potential rod undesired movement. The annunciator relies on the recorder or plant computer alarm contact activated by a state change in stationary gripper coil status based on a low or high voltage, indicative of a gripper coil change of state. The actions prescribed in the Annunciator Response and Off Normal Operating procedures for a change in the gripper value are the same as those for a rod that is indicated to be deviating based on an individual RPI.

Impact on Indications and Alarms:

The following table provides a summary of the indications and alarms and how they are affected by the an inoperable RPI for a control rod or shutdown rod:

Indication /

Function Alarm Normal Operation Affect of Modified Operation Identification Provides analog rod This indication will be disabled and Analog Meter RPI position reading for considered out-of-service for the control Indication Panel inoperable control rod or shutdown rod with an inoperable rod or shutdown rod. RPI.

Lights illuminate- This indication will be disabled and Rod Bottom when any rod is considered out-of-service for the control Indication Control Panel within 20 steps or rod or shutdown rod with an inoperable Lights closer to the bottom RPI. The lights will not be capable of of the core. illumination.

This annunciation is actuated when any The ability of the control rod or shutdown Annunciator rod is within 20 rod with an inoperable RPI to actuate this Rod Bottom / window B7/1 steps or closer to annunciation will be disabled. All other Rod Drop - NIS / RPI the bottom of the control rods or shutdown rods with Annunciation Rod Drop core. operable RPIs will actuate this Rod Stop annunciatior.

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 8 of 9 Rod Position Indication Systems This annunciation is actuated for any deviation of 12 (24 moving) steps The ability of the control rod or shutdown Annunciator between any two rod with an inoperable RPI to actuate this Rod window B9/3 - rods in the same annunciation will be disabled. All other Deviation Rod bank or any control rods or shutdown rods with Annunciation Deviation shutdown rod below operable RPIs will actuate this 218 steps and annunciatior.

control rod bank B greater than 35 steps.

4 4- 4 This annunciation is actuated for any control rod bank at or below its B8/2:1o-lo limit (Banks A & B Annunciator

- 203 steps, Banks windows C & D variable per This annunciation relies on the group step Rod Insertion B 8/1 & B8/2 - COLR rod insertion counter demand position indication and is Limit Monitor Rod Bank limit) and B8/1: lo- unaffected by an out-of-service Analog A/B/C/D Low limit (Banks A & B - RPI for a control rod.

Limit & Extra 223 steps, Bank C Low Limit 10 steps above Io-lo limit and Band D 20 steps above Io-lo limit)

Provide a single An additional recorder channel indication Gross continuous will be added to the function of the Megawatts Recorder on recording of the equipment. This indication will provide Recorder Panel 3/4C04 gross megawatts continuous recording and indication of the from the main Stationary Gripper status for a control rod generator. or shutdown rod with an inoperable RPI.

High and low alarm indication light Gross Recorder on No alarms are settings will be provided on this recorder Megawatts Panel 3/4C04 utilized on this for the Stationary Gripper status for a Recorder recorder. control rod or shutdown rod with an inoperable RPI.

This annunciation is This annunciator relies on the control actuated for any room recorder or plant computer alarm Rod Trouble Annunciator high or low gripper contact activated by a state change in Monitor window coil voltage from the stationary gripper coil voltage status for a recorder or plant control rod or shutdown rod with an computer inoperable RPI.

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 1 License Amendment Request - LAR 194 Page 9 of 9 Rod Position Indication Systems Compensatory Measures The following compensatory measures will be used to offset the loss of indication and alarms affected by an inoperable RPI for a control rod or shutdown rod:

For the Analoq Meter Indication:

The specific position indication of height for the control rod or shutdown rod with an inoperable RPI will not be available on the alternate monitoring equipment but will be compensated for by performing flux traces. Flux traces will be required following rod motion that affects the control bank or shutdown bank with the inoperable RPI. This measure will be procedurally driven by the general operating procedures that govern reactor operation and the surveillance procedure that exercises all of the rods on a routine basis. The flux traces during the rod exercising procedure will be performed following the insertion of a control rod bank or shutdown rod bank and following the subsequent withdrawal to All Rods Outs as defined in the Core Operating Limits Report.

For the Rod Bottom Li-iht Indication and Rod Bottom Annunciation Alarm:

The Rod Bottom Light and Rod Bottom Annunciation Alarm that will not be available on the alternate monitoring equipment will be compensated for by the procedurally driven requirement to perform a flux trace any time a change in state is indicated on the recorder. In the case of an indicated dropped rod on the individual rod position indicator for a control rod or shutdown bank with an inoperable RPI, the Operators will monitor the plant response as trained for a Dropped Rod event. They will specifically monitor for changes in RCS temperature and pressure, changes of indicated reactor power and indicated neutron flux, changes in generator output and pressurizer level. If no changes in plant parameters are noted along with no change in state based on the alternate monitoring indication, a flux trace is still procedurally required. If changes are noted in plant parameters, it will be assumed that the rod has dropped and required actions will be taken. If another rod drops in conjunction with the indications discussed for a control rod or shutdown rod with an inoperable RPI, it will be assumed that two rods have dropped and Operators will take appropriate actions.

For the Rod Deviation Annunciation Alarm:

The Rod Deviation Annunciation Alarm that will be lost for the control rod or shutdown rod with an inoperable RPI, will be compensated by flux traces driven from the Annunciator Response procedure as well as the routine surveillance procedure when a gripper coil change in state is observed on the alternate monitoring equipment.

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 2 License Amendment Request Page 1 of 3 Position Indication Systems DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 2 License Amendment Request Page 2 of 3 Position Indication Systems DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION Description Of Proposed License Amendment The proposed amendment would revise TS 3.1.3.2 to allow use of an alternate method of determining rod position for a shutdown or control rod with an inoperable RPI. The method to be used will monitor the stationary gripper coil of the Control Rod Drive Mechanism (CRDM) for the control or shutdown rod with an inoperable analog RPI. The proposed amendment will provide a less burdensome monitoring method than currently required by TS 3.1.3.2 when problems with the analog RPI system are experienced. When a problem in the RPI system requires the monitoring of a rod's position by the alternate means, FPL plans to continue unit operation until the unit enters Mode 3 when the inoperable RPI will be repaired.

Introduction The Commission has provided standards for determining whether a significant hazards consideration exists as stated in 10 CFR 50.92. A proposed amendment to an operating license for a facility involves no significant hazards consideration if operation of the facility in accordance with a proposed amendment would not: (1) involve a significant increase in the probability or consequences of an accident previously evaluated; or (2) create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) involve a significant reduction in a margin of safety.

Florida Power and Light Company (FPL) has concluded that the proposed amendment to the Turkey Point Units 3 and 4 operating licenses does not involve a significant hazards consideration.

In support of this determination, an evaluation of each of the three standards set forth in 10 CFR 50.92 is provided below.

1. Will operation of the facility in accordance with this proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

No. The proposed change provides an alternative method for verifying rod position of one control rod or shutdown rod with an inoperable rod position indicator (RPI). The proposed change meets the intent of the current specification in that it ensures verification of position of the control rod or shutdown rod within one hour of unintended rod motion and at least once every eight (8) hours. The proposed change provides only an alternative method of monitoring control rod position and does not change the assumption or results of any previously evaluated accident.

Therefore, operation of the facility in accordance with the proposed amendment would not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Will operation of the facility in accordance with this proposed change create the possibility of a new or different kind of accident from any accident previously evaluated?

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 2 License Amendment Request Page 3 of 3 Position Indication Systems No. As described above, the proposed change provides only an alternative method of determining the position of one control rod or shutdown rod with an inoperable RPI. No new accident initiators are introduced by the proposed alternative manner of performing rod position verification. The proposed change does not affect the reactor protection system or the reactor control system. Hence, no new failure modes are created that would cause a new or different kind of accident from any accident previously evaluated.

Therefore, operation of the facility in accordance with the proposed amendments would not create the possibility of a new or different kind of accident from any accident previously evaluated.

3. Will operation of the facility in accordance with this proposed change involve a significant reduction in a margin of safety?

No. The bases of Specification 3.1.3.2 state that the operability of the rod position indicators is required to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits. The proposed change does not alter the requirement to determine rod position but provides an alternative method for determining the position of control rod or shutdown rod with an inoperable RPI. As a result, the initial conditions of the accident analysis are preserved and the consequences of previously analyzed accidents are unaffected.

Therefore, operation of the facility in accordance with the proposed amendments would not involve a significant reduction in the margin of safety.

Based on the reasoning presented above, FPL has determined that the requested changes involve no significant hazards consideration.

Environmental Consideration The proposed license amendment changes requirements with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The proposed amendment involves no significant increase in the amounts and no significant change in the types of any effluents that may be released offsite, and no significant increase in individual or cumulative occupational radiation exposure. FPL concluded that the proposed amendment involves no significant hazards consideration and meets the criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9) and that, pursuant to 10 CFR 51.22(b), an environmental impact statement or environmental assessment need not be prepared in connection with issuance of the amendment.

Conclusion FPL concludes, based on the considerations discussed above, that (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 detrimental to the common defense and security or to the health and safety of the public.

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 3 License Amendment Request - LAR 194 Page 1 of 3 Position Indication Systems TURKEY POINT UNITS 3 AND 4 MARKED-UP TECHNICAL SPECIFICATION PAGES Page 3/4 1-20

REACTIVITY CONTROL SYSTEMS POSITION INDICATION SYSTEMS - OPERATING LIMITING CONDITION FOR OPERATION (Continued) 3.1.3.2 The Analog Rod Position Indication System

  • and the Demand Position Indication System shall be OPERABLE and capable of determining the respective actual and demanded shutdown and control rod positions as follows:
a. Analog rod position indicators *, within one hour after rod motion (allowance for thermal soak);

All Shutdown Banks: within the Allowed Rod Misalignment of Specification 3.1.3.1 of the group demand counters for withdrawal ranges of 0-30 steps and 200-All Rods Out as defined in the Core Operating Limits Report.

Control Bank A and B: within the Allowed Rod Misalignment of Specification 3.1.3.1 of the group demand counters for withdrawal ranges of 0-30 steps and 200-All Rods Out as defined in the Core Operating Limits Report.

Control Banks C and D: within the Allowed Rod Misalignment of Specification 3.1.3.1 of the group demand counters for withdrawal range of 0-All Rods Out as defined in the Core Operating Limits Report.

b. Group demand counters; +/-2 steps.

APPLICABILITY: MODES 1 and 2.

ACTION:

a. With a maximum of one analog rod position indicator per bank inoperable either:
1. Determine the position of thenon-indicating rod(s)
  • indirectly by the movable incore detectors at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and within one hour after any motion of the non-indicating rod which exceeds 24 steps in one direction since the last determination of the rod's position, or

. Reduce THERMAL POWER to less than 75% of RATED THERMAL POWER. within

  • 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
b. With a maximum of one demand position indicator per bank inoperable either:
1. Verify that all analog rod position indicators foe the affected bank are OPERABLE and that the most withdrawn rod and the least withdrawn rod of the bank are within the Allowed Rod Misalignment of Specification 3.1.3.1 at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, or
2. Reduce THERMAL POWER to less than 75% of RATED THERMAL POWER within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
  • During Unit 4 Cycle 21, the position of Rod F-8 Shutdown Bank B will be determined every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> by verifying gripper coil parameters of the Control Rod Drive Mechanism to determine it has not changed state, until the repair of the indication system for this rod is completed.
  • During Unit 3 Cycle 22, the position of Rod M-6, Control Bank C will be determined every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> by verifying gripper coil parameters of the Control Rod Drive Mechanism to determine it has not changedstate, Until the repair of the indication system for this rod is completed.

1 .:l3 TURKEY POINT- UNITS 3 & 4 3/4 1-20 AMENDMENT NOS.00AND4r'

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 3 License Amendment Request - LAR 194 Page 3 of 3 Position Indication Systems Insert A 2** a). Determine the position of the non-indicating rod indirectly by the movable incore detectors within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and once every 31 Effective Full Power Days. thereafter, and within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> if rod control system parameters indicate unintended movement, or if the rod with an inoperable position indicator is moved greater than 12 steps, and b). Review the parameters of the rod control system for indications of unintended rod movement for the rod with an inoperable indicator within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and c). Determine the position of the non-indicating rod indirectly by the movable incore detectors prior to increasing THERMAL POWER above 50% RATED THERMAL POWER and within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of reaching 100% RATED THERMAL POWER, or Insert B

    • Rod position monitoring by Actions a.2.a), a.2.b), and a.2.c) may only be applied to one inoperable rod position indicator per unit and shall only be allowed until an entry into MODE 3.

Turkey Point Units 3 and 4 L-2007-175 Docket Nos. 50-250 and 50-251 Attachment 4 License Amendment Request - LAR 194 Page 1 of 3 Position Indication Systems TURKEY POINT UNITS 3 AND 4 CLEAN TECHNICAL SPECIFICATION PAGES Page 3/4 1-20 Page 3/4 1-20a

REACTIVITY CONTROL SYSTEMS POSITION INDICATION SYSTEMS - OPERATING LIMITING CONDITION FOR OPERATION (Continued) 3.1.3.2 The Analog Rod Position Indication System

  • and the Demand Position Indication System shall be OPERABLE and capable of determining the respective actual and demanded shutdown and control rod positions as follows:
a. Analog rod position indicators *, within one hour after rod motion (allowance for thermal soak);

All Shutdown Banks: within the Allowed Rod Misalignment of Specification 3.1.3.1 of the group demand counters for withdrawal ranges of 0-30 steps and 200-All Rods Out as defined in the Core Operating Limits Report.

Control Bank A and B: within the Allowed Rod Misalignment of Specification 3.1.3.1 of the group demand counters for withdrawal ranges of 0-30 steps and 200-All Rods Out as defined in the Core Operating Limits Report.

Control Banks C and D: within the Allowed Rod Misalignment of Specification 3.1.3.1 of the group demand counters for withdrawal range of 0-All Rods Out as defined in the Core Operating Limits Report.

b. Group demand counters; +/- 2 steps.

APPLICABILITY: MODES 1 and 2.

ACTION:

a. With a maximum of one analog rod position indicator per bank inoperable either:
1. Determine the position of the non-indicating rod(s)
  • indirectly by the movable incore detectors at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and within one hour after any motion of the non-indicating rod which exceeds 24 steps in one direction since the last determination of the rod's position, or 2** a). Determine the position of the non-indicating rod indirectly by the movable incore detectors within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and once every 31 Effective Full Power Days thereafter, and within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> if rod control system parameters indicate unintended movement, or if the rod with an inoperable position indicator is moved greater than 12 steps, and b). Review the parameters of the rod control system for indications of unintended rod movement for the rod with an inoperable indicator within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter, and c). Determine the position of the non-indicating rod indirectly by the movable incore detectors prior to increasing THERMAL POWER above 50% RATED THERMAL POWER and within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> of reaching 100% RATED THERMAL POWER, or
3. Reduce THERMAL POWER to less than 75% of RATED THERMAL POWER within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.

TURKEY POINT - UNITS 3 &4 3/4 1-20 AMENDMENT NOS. AND

REACTIVITY CONTROL SYSTEMS POSITION INDICATION SYSTEMS - OPERATING LIMITING CONDITION FOR OPERATION (Continued)

ACTION (Continued):

b. With a maximum of one demand position indicator per bank inoperable either:
1. Verify that all analog rod position indicators for the affected bank are OPERABLE and that the most withdrawn rod and the least withdrawn rod of the bank are within the Allowed Rod Misalignment of Specification 3.1.3.1 at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, or
2. Reduce THERMAL POWER to less than 75% of RATED THERMAL POWER within 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />.
  • During Unit 4 Cycle 21, the position of Rod F-8 Shutdown Bank B will be determined every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> by verifying gripper coil parameters of the Control Rod Drive Mechanism to determine it has not changed state, until the repair of the indication system for this rod is completed.
  • During Unit 3 Cycle 22, the position of Rod M-6, Control Bank C will be determined every 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> by verifying gripper coil parameters of the Control Rod Drive Mechanism to determine it has not changed state, until the repair of the indication system for this rod is completed.
    • Rod position monitoring by Actions a.2.a), a.2.b), and a.2.c) may only be applied to one inoperable rod position indicator per unit and shall only be allowed until an entry into MODE 3.

TURKEY POINT - UNITS 3 &4 3/4 1-20a AMENDMENT NOS. AND

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